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Microfacies of Deep-water Deposits and Forming Models of the Chinese Continental Scientific Drilling-SKII 被引量:4
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作者 CHENG Rihui WANG Guodong WANG Pujun GAO Youfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第6期1026-1032,共7页
Extensive transgression of lake water occurred during the Cretaceous Qingshankou Stage and the Nengjiang Stage in the Songliao basin, forming widespread deep-water deposits. Eleven types of microfacies of deep-water d... Extensive transgression of lake water occurred during the Cretaceous Qingshankou Stage and the Nengjiang Stage in the Songliao basin, forming widespread deep-water deposits. Eleven types of microfacies of deep-water deposits have been recognized in the continuous core rocks from the SKII, including mudstone of still water, marlite, dolostone, off shale, volcanic ashes, turbidite, slump sediment, tempestite, seismite, ostracoda limestone and sparry carbonate, which are divided into two types: microfacies generated due to gradually changing environments (Ⅰ) and microfacies generated due to geological events (Ⅱ). Type Ⅰ is composed of some special fine grain sediments such as marlite, dolomite stone and oil shale as well as mudstone and Type Ⅱ is composed of some sediments related to geological events, such as volcanic ashes, turbiditie, slump sediment, tempestite, seismite, ostracoda limestone. The formation of sparry carbonate may be controlled by factors related to both environments and events. Generally, mudstone sediments of still water can be regarded as background sediments, and the rest sediments are all event sediments, which have unique forming models, which may reflect controlling effects of climatics and tectonics. 展开更多
关键词 CRETACEOUS deep-water deposit model of microfacies Songliao basin SKII
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Cambrian- Ordovician Deep - Water Deposits in Southwest Jiangxi, China
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作者 Ji LeiNanjing Institute of Geography and Limnology, Academia Sinica, Nanjing Jiang Minxi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1994年第4期435-449,471-472,共17页
The Cambrian-Ordovician rocks in southwestern Jiangxi are mainly composed of deep-water deposits, in which 5 facies have been recognized: sandstone facies, sandstone-mudstone facies, siltstone-mudstone facies, mudston... The Cambrian-Ordovician rocks in southwestern Jiangxi are mainly composed of deep-water deposits, in which 5 facies have been recognized: sandstone facies, sandstone-mudstone facies, siltstone-mudstone facies, mudstone (slate)facies, and chert facies. They are of turbidity current origin and are related to pelagic and hemipelagic deposits. In the light of facies distribution, the Cambrian-Ordovician deposits can be classified into 3 facies associations formed in middle fan, outer fan and deep-sea plain environments respectively. The 3 different orders of vertical cycles in the stratigraphic sequence are considered to be controlled by factors such as sea-level fluctuation, basin subsidence and submarine fan progradation. The tectonic setting of the sedimentary basin is interpreted as passive continental margin based on the chemical composition analysis of the sandstone. 展开更多
关键词 deep-water deposits TURBIDITE pelagite and hemipelagite submarine fan vertical cycles
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Measurements of Fog Water Deposition on the California Central Coast 被引量:1
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作者 Cyrus Hiatt Daniel Fernandez Christopher Potter 《Atmospheric and Climate Sciences》 2012年第4期525-531,共7页
Fog deposition is a notable component of the water budget of herbaceous-shrub ecosystems on the central and southern coastal regions of California. This paper presents an analysis of fog water deposition rates and met... Fog deposition is a notable component of the water budget of herbaceous-shrub ecosystems on the central and southern coastal regions of California. This paper presents an analysis of fog water deposition rates and meteorological controls in Big Sur, California. Mesh-screen fog collectors were installed the Brazil Ranch weather station sites to measure fog water during the summer seasons of 2010 and 2011. Fog deposition occurred during 73% of days recorded in 2010 and 87% of days recorded in 2011. The daily average deposition rate was 2.29 L/m2 in 2010 and 3.86 L/m2 in 2011. The meteorological variables which had the greatest influence on prediction of fog deposition were wind speed, wind direction, and the dew-point depression (difference between air temperature and dew point). Based on these results, we hypothesize that high rates of summer fog deposition help sustain the productivity of California coastal vegetation through periods of low rainfall. 展开更多
关键词 FOG depositION California STYLING water BUDGET
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Principles of Technology for Bottling Medicinal Mineral Waters of Sairme Using the Example of Source №3a
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作者 Irina Nikolaishvili Giorgi Kvartskava 《American Journal of Analytical Chemistry》 CAS 2024年第4期135-138,共4页
Sairme mineral water, one of the famous mineral waters in Georgia, is renowned for its exceptional healing properties. The distinctiveness and therapeutic benefits of the naturally sourced mineral water, known as “Sa... Sairme mineral water, one of the famous mineral waters in Georgia, is renowned for its exceptional healing properties. The distinctiveness and therapeutic benefits of the naturally sourced mineral water, known as “Sairme”, stem from its rich array of microelements, notably including iron and manganese. Since 1948, the bottling of Sairme mineral water has been a prominent activity. Named after the Sairme deposit, this mineral water is packaged in various formats to cater to diverse consumer preferences. The bottling process involves transporting the mineral water from wells to the bottling plant through pipelines. Prior to bottling, the mineral water undergoes meticulous processing stages in adherence to current Georgian and international regulations. This process ensures that the concentration of trace elements in the bottled water is minimized, maintaining its purity and quality. Given the importance of preserving the microelements present in bottled mineral water, our research is dedicated to optimizing the technological process. Our objective is to safeguard the valuable microelements while ensuring the highest standards of quality and safety in the final product. 展开更多
关键词 Sairme Mineral water deposit Oxidation-Reduction Potential Trace Elements Chemical Composition SEASONALITY
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Impact of the 6 February 2023 Earthquake in Turkey on Borjomi Mineral Water Wells
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作者 Nino Shavgulidze Nana Zautashvili 《Open Journal of Geology》 2023年第7期773-781,共9页
The study of Borjomi mineral water deposit starts from the 30 s of XIX century. Chemical composition of Borjomi deposit mineral water is of great importance for study of issues of mineral water formation, creation of ... The study of Borjomi mineral water deposit starts from the 30 s of XIX century. Chemical composition of Borjomi deposit mineral water is of great importance for study of issues of mineral water formation, creation of geodynamic model of the deposit and increasing of useful resources. The impact of several strong earthquakes in the region on the wells of the deposit is described. Stability of chemical composition of Borjomi deposit mineral water is proved. 展开更多
关键词 Borjomi Mineral water deposit Useful Resources of Mineral water EARTHQUAKE Chemical Composition TDS
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Numerical Simulation of Water Droplets Deposition on the Last-Stage Stationary Blade of Steam Turbine 被引量:3
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作者 Danmei Xie Xinggang Yu +3 位作者 Wangfan Li Youmin Hou Yang Shi Sun Cai 《Energy and Power Engineering》 2010年第4期248-253,共6页
Based on the method of discrete phase, the law of droplets’ deposition in the last stage stationary blade of a supercritical 600 MW Steam Turbine is simulated in the first place of this paper by using the Wet-steam m... Based on the method of discrete phase, the law of droplets’ deposition in the last stage stationary blade of a supercritical 600 MW Steam Turbine is simulated in the first place of this paper by using the Wet-steam model in commercial software FLUENT, where the influence of inlet angle of water droplets of the stationary blades is also considered. Through the calculation, the relationship between the deposition and the diameter of water droplets is revealed. Then, the amount of droplets deposition in the suction and pressure surface is derived. The result is compared with experimental data and it proves that the numerical simulation result obtained in this paper is reasonable. Finally, a formula of the relationship between the diameter of water droplets and the inlet angle is fit, which could be used for approximate calculation in the engineering applications. 展开更多
关键词 STEAM Turbine STATIONARY BLADE Wet STEAM water Droplets depositION Discrete Phase Numerical Simulation
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The Development of a Simulated Sediment Dosing Apparatus for Deposition Research in Wastewater Collection Systems 被引量:1
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作者 David Campbell Sean Mushin Craig Saunders 《Journal of Water Resource and Protection》 2018年第5期493-506,共14页
Water conservation initiatives promote installation of water efficient and low-flow appliances in waste water collection systems. This has resulted in lower flow rates in those systems than the intended design loading... Water conservation initiatives promote installation of water efficient and low-flow appliances in waste water collection systems. This has resulted in lower flow rates in those systems than the intended design loading, causing solid deposition and sedimentation in some areas. A joint UKWIR/EPSRC CASE grant (14440031) has funded the work described in this paper which investigates sedimentation and solid deposition in building drainage system pipes. The purpose of this paper is to detail the design, calibration and operation of a sediment dosing apparatus to simulate sedimentation rates and explore possible solutions to this issue with a full scale laboratory model based on real site data. The methodology adopted is an experimental approach, where tests have been conducted on the sediment dosing apparatus based on calculations and observations to determine an appropriate sediment dosing regime representative of typical systems. Further tests were conducted with the addition of everyday household products to investigate their effects on sedimentation. The results indicated that a suitable dosing rate was approximately 12% weight-to-volume (w/v) of a fine sand with a known particle size distribution, diluted 1:5 in a clean water base flow. It was also shown that the addition of the household products added to the problem of sedimentation within drainage systems. The results give excellent correlation to real site data, with deposition depth and distribution comparable to measured site data to within 10%. The deposition was achieved within three hours, which approximated six weeks deposition in the live site used in the study. This straightforward investigation details the design, construction and testing of a device to cause accelerated sedimentation in a full scale model of a building drainage system. This is the first step in the process of updating research underpinning our understanding of the behaviour of these systems under conditions of low flow rates caused by water conservation, sedimentation, and the use of common household additives. It will be used to improve simulation of water flow and solid transport in sediment-laden systems. Specifically, the results will be used to determine refinements required to a specific drainage simulation model (DRAINET), which currently has an unquantified sedimentation component. This work is part of a larger body of current research funded by two joint EPSRK/UKWIR grants. 展开更多
关键词 water CONSERVATION depositION Modelling Computer Simulation Empirical Model SITE Sampling
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Status and Trends in Research on Deep-Water Gravity Flow Deposits 被引量:18
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作者 YANG Tian CAO Yingchang +2 位作者 WANG Yanzhong LI Ya ZHANG Shao Min 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第2期610-631,共22页
Deep-water gravity flows are one of the most important sediment transport mechanisms on Earth. After 60 years of study, significant achievements have been made in terms of classification schemes, genetic mechanisms, a... Deep-water gravity flows are one of the most important sediment transport mechanisms on Earth. After 60 years of study, significant achievements have been made in terms of classification schemes, genetic mechanisms, and depositional models of deep-water gravity flows. The research history of deep-water gravity flows can be divided into five stages: incipience of turbidity current theory; formation of turbidity current theory; development of deep-water gravity flow theory; improvement and perfection of deep-water gravity flow theory; and comprehensive development of deep-water gravity flow theory. Currently, three primary classification schemes based on the sediment support mechanism, the rheology and transportation process, and the integration of sediment support mechanisms, rheology, sedimentary characteristics, and flow state are commonly used.Different types of deep-water gravity flow events form different types of gravity flow deposits. Sediment slump retransportation mainly forms muddy debris flows, sandy debris flows, and surge-like turbidity currents. Resuspension of deposits by storms leads to quasi-steady hyperpycnal turbidity currents (hyperpycnal flows). Sustainable sediment supplies mainly generate muddy debris flows, sandy debris flows, and hyperpycnal flows. Deep-water fans, which are commonly controlled by debris flows and hyperpycnal flows, are triggered by sustainable sediment supply; in contrast, deep-water slope sedimentary deposits consist mainly of debris flows that are triggered by the retransportation of sediment slumps and deep-water fine-grained sedimentary deposits are derived primarily from fine- grained hyperpycnal flows that are triggered by the resuspension of storm deposits. Harmonization of classification schemes, transformation between different types of gravity flow deposit, and monitoring and reproduction of the sedimentary processes of deep-water gravity flows as well as a source-to-sink approach to document the evolution and deposition of deep-water gravity flows are the most important research aspects for future studies of deep-water gravity flows study in the future. 展开更多
关键词 Development history TURBIDITY debris flows deep-water gravity flows genesis depositional model
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Effect of Talus Deposit Excavations on Hydrogeochemical Characteristics of Kuvars Spring Water, Maltepe, Istanbul, Turkey
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作者 Rustem Pehlivan Hasan Emre Deniz Key 《Journal of Water Resource and Protection》 2012年第5期294-306,共13页
Spring waters consumed for drinking purposes should be clean and quality. These waters with balanced mineral distribution, which do not contain organic substances, whose physical and chemical caharacteristics comply w... Spring waters consumed for drinking purposes should be clean and quality. These waters with balanced mineral distribution, which do not contain organic substances, whose physical and chemical caharacteristics comply with certain quality parameters and which do not negatively affect human health are identified as healthy water. Kuvars water is a spring water which is pumped out from the draw well at the Camurluk stream basin of Maltepe province of Istanbul and filled into bottles. The Camurluk stream basin is approximately 4.5 km2. The Camurluk stream basin is sedimentary rocks and talus deposit outcrops. Reaching of trace elements, which is found more in the talus deposit samples than outcropping quartzarenite at the basin, to underground aquifer as ions under effect of rains, water rock interaction, leakage and filtration, is prevented by illite type clay levels existing within the talus deposit stack, which have upto 20 cm thickness. However, negative effects of the excavation that were made at the talus deposit reflect on the hydrologic cycle and chemical compositions of well waters. This effect was at first negatively affected the physical characteristics of the well waters. During the rainy periods, the water in the excavated area which was enriched with respect to the suspended sediments was percolated into the groundwaters from the joints and cracks of the quartzarenite. The turbidity value measured in the well waters of K2 and K3 were determined as 40.3 NTU and 34.2 NTU respectively. Although at the basin, the aquifer of underground water and the well waters being managed are quartzarenite, the fact that water types belonging to well waters differ (they are not same) according to the Piper diagram and when the heavy metal content of the water of well numbered KS1 is taken as basis, that some heavy metals such as Al3+, Fe2+, Ni2+, Mn2+ and Cu2+ be enriched 3 to 40 times in KS2 and KS3 well waters, are caused by talus deposit—water interaction at the excavation area. After a rainfall, in the water that became turbid with the water-talus deposit interaction at the excavation area, the water-mineral interaction has caused the limit value for drinking water suggested by World Health Organization (WHO) to be exceeded with the Al3+ concentration of 189 ppb detected in KS2 well water and Fe2+ concentration of 185 ppb has caused to approach the drinking water limit value of 200 ppb permitted by World Health Organization (WHO), United States Environmental Protection Agency (EPA), European Union (EU) and Turkish Standards (TS). Therefore, at the water basins where bottled spring waters consumed for drinking purposes are produced, technical undertakings that shall disturb the stability of geological units should not be permitted. 展开更多
关键词 HYDROGEOCHEMISTRY Kuvars water TALUS deposit Excavation water Guality TURKIYE
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Effects of Material Composition and Water Content on the Mechanical Properties of Landslide Deposits Triggered by the Wenchuan Earthquake 被引量:10
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作者 ZHOU Jiawen CUI Peng YANG Xingguo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期242-257,共16页
Abundant landslide deposits were triggered by the Wenchuan earthquake, providing a rich source of material for subsequent debris flows or slope failures under rainfall conditions. A good understanding of the physical ... Abundant landslide deposits were triggered by the Wenchuan earthquake, providing a rich source of material for subsequent debris flows or slope failures under rainfall conditions. A good understanding of the physical and mechanical properties of the landslide deposits is very important to the research on slope failure mechanisms and the initiation of debris flow. Laboratory biaxial compression tests are used to study the material compositions and water content impacts on the mechanical properties of landslide deposits, and a discrete element method (a bond-contact model) is used to study the particle stiffness, bond force, friction coefficient and confining stress impact on the mechanical behaviors and the relationships between the numerical and experimental parameters. The experimental results show that the failure stress of landslide deposits is decreased with increasing content of fine particles and also with increased water content, especially at the initial increasing stage. Cohesion of the saturated landslide deposits is increased, but the friction angle is decreased with the increase in the fine particle content. Shear strength parameters (the cohesion and friction angle) are decreased with the increasing water content at the initial increasing stage, and then, they slowly decrease. There is a critical value of the water content at 5%-7% (in weight) for the failure stress and shear strength parameters of the landslide deposits. Quadratic equations are presented to describe the relation between the bond force and cohesion, and the numerical friction coefficient and the experimental friction angle. 展开更多
关键词 landslide deposits particle size distribution water content shear strength parameters numerical modeling
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Sedimentary facies and depositional model of shallow water delta dominated by fluvial for Chang 8 oil-bearing group of Yanchang Formation in southwestern Ordos Basin,China 被引量:11
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作者 陈林 陆永潮 +5 位作者 吴吉元 邢凤存 刘璐 马义权 饶丹 彭丽 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4749-4763,共15页
A systematic analysis of southwestern Ordos Basin's sedimentary characteristics,internal architectural element association styles and depositional model was illustrated through core statistics,well logging data an... A systematic analysis of southwestern Ordos Basin's sedimentary characteristics,internal architectural element association styles and depositional model was illustrated through core statistics,well logging data and outcrop observations in Chang 8 oil-bearing group.This analysis indicates that shallow water delta sediments dominated by a fluvial system is the primary sedimentary system of the Chang 8 oil-bearing group of the Yanchang Formation in southwestern Ordos Basin.Four microfacies with fine grain sizes are identified: distributary channels,sheet sandstone,mouth bar and interdistributary fines.According to the sandbody's spatial distribution and internal architecture,two types of sandbody architectural element associations are identified: amalgamated distributary channels and thin-layer lobate sandstone.In this sedimentary system,net-like distributary channels at the delta with a narrow ribbon shape compose the skeleton of the sandbody that extends further into the delta front and shades into contiguous lobate distribution sheet sandstone in the distal delta front.The mouth bar is largely absent in this system.By analyzing the palaeogeomorphology,the palaeostructure background,sedimentary characteristics,sedimentary facies types and spatial distribution of sedimentary facies during the Chang 8 period,a distinctive depositional model of the Chang 8 shallow water fluvial-dominated delta was established,which primarily consists of straight multi-phase amalgamated distributary channels in the delta plain,net-like distributary channels frequently diverting and converging in the proximal delta front,sheet sandstones with dispersing contiguous lobate shapes in the distal delta front,and prodelta or shallow lake mudstones. 展开更多
关键词 sedimentary facies architectural element depositIONAL model shallow water delta CHANG 8 oil-bearing GROUP ORDOS Basin
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Magnitude and Trends of High-elevation Cloud Water Pollutant Concentrations and Modeled Deposition Fluxes
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作者 Selma Isil Thomas Lavery +2 位作者 Kristi Gebhart Christopher Rogers Carol Armbrust Wanta 《Journal of Environmental Science and Engineering(B)》 2017年第3期127-143,共17页
关键词 污染物浓度 沉积通量 高海拔 云水 模拟 氮氧化物排放量 美国环境保护局 液态水含量
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Analysis on thermophoretic deposit of fine particle on water wall of 10 MW high temperature gas-cooled reactor 被引量:1
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作者 ZHOUTao YANGRui-Chang JIADou-Nan 《Nuclear Science and Techniques》 SCIE CAS CSCD 2005年第1期46-52,共7页
The water wall is an important part of the passive natural circulation residual heat removal system in a high temperature gas-cooled reactor. The maximum temperatures of the pressure shell and the water wall are calcu... The water wall is an important part of the passive natural circulation residual heat removal system in a high temperature gas-cooled reactor. The maximum temperatures of the pressure shell and the water wall are calcu- lated using annular vertical closed cavity model. Fine particles can deposit on the water wall due to the thermophore- sis effect. This deposit can affect heat transfer. The thermophoretic deposit efficiency is calculated by using Batch and Shen’s formula fitted for both laminar flow and turbulent flow. The calculated results indicate that natural convection is turbulent in the closed cavity. The transient thermophoretic deposit efficiency rises with the increase of the pressure shell’s temperature. Its maximum value is 14%. 展开更多
关键词 高温气冷反应堆 压水堆 放射性微粒 热敏致电沉积 安全防护
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Seabed deposition and erosion change and influence factors in the Yangshan Deepwater Port over the years 被引量:2
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作者 Shuhua Zuo Hualiang Xie +4 位作者 Xiaoming Ying Cheng Cui Yuxin Huang Huaiyuan Li Mingxiao Xie 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第7期96-106,共11页
The seabed scouring and silting are very important to the construction of port and waterway engineering.Seabed deposition and erosion change is complicated due to the influence of sediment supply,human activities and ... The seabed scouring and silting are very important to the construction of port and waterway engineering.Seabed deposition and erosion change is complicated due to the influence of sediment supply,human activities and other factors.The Yangshan Deepwater Port is the new deep water harbor,which is an important part of the Shanghai International Shipping Service Center.Its construction has received much attention.At present,the water depth from the 1st to the 3rd harbor district is currently suitable under regular dredging and tidal current action.The fourth harbor district will be built in the world’s largest fully-automated deep water wharf.In the study,bathymetry change of the entire sea area of the Yangshan Deepwater Port and the 4th harbor district(i.e.,PhaseⅣproject)waters were analyzed quantitatively using multiyear bathymetric,hydrological and sediment data.The results show that from 1998 to 2010,seabed changes are characterized by large volumes of erosion and sedimentation,which the southern part was deposited and the northern part was eroded in the inner harbor waters,but the seabed of the Kezhushan inlet was eroded.Seabed changes of PhaseⅣproject waters generally show a scour tendency in recent few years with the annual scour rate about 0.7 m.Among the many factors,the existence of Kezhushan inlet and its influence of the western water flow play an important positive role in water depth changes under the ebb tide action. 展开更多
关键词 Yangshan Deepwater Port phaseⅣproject water and sediment environment SEABED depositION and EROSION CHANGE DIVERSION DIKE
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Polycyclic aromatic hydrocarbon deposition to and exchange at the air-water interface of Luhu, an urban lake in Guangzhou, China
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作者 Jun LI Gan ZHANG +2 位作者 Shihua QI Lingli GUO Xianzhi PENG 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期189-190,共2页
关键词 PAHS 空气 沉积作用 交换作用 湖泊
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Applications of sediment sudden deposition model based on the third-generation numerical model for shallow water wave
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作者 BAI Yuchuan ZHANG Yinqi ZHANG Bin 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2007年第3期142-149,共8页
The existing numerical models for nearshore waves are briefly introduced, and the third-generation numerical model for shallow water wave, which makes use of the most advanced productions of wave research and has been... The existing numerical models for nearshore waves are briefly introduced, and the third-generation numerical model for shallow water wave, which makes use of the most advanced productions of wave research and has been adapted well to be used in the environment of seacoast, lake and estuary area, is particularly discussed. The applied model realizes the significant wave height distribution at different wind directions. To integrate the model into the coastal area sediment, sudden deposition mechanism, the distribution of average silt content and the change of sediment sudden deposition thickness over time in the nearshore area are simulated. The academic productions can give some theoretical guidance to the applications of sediment sudden deposition mechanism for stormy waves in the coastal area. And the advancing directions of sediment sudden deposition model are prospected. 展开更多
关键词 Boussinesq equation mild-slope equation third-generation numerical model for shallow water wave sedimentsudden deposition
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Where were the Metal, Sulfur and Water from in the Postcollisional Porphyry Cu Deposit at Qulong in South Tibet?
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作者 QU Huanchun SUN Maoyu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第2期753-754,共2页
Objective Most porphyry Cu deposits (PCDs) were formed in association with subduction-related calc-alkaline magmas, which occurred widely in magmatic arcs worldwide. A widely accepted model is that such deposits wer... Objective Most porphyry Cu deposits (PCDs) were formed in association with subduction-related calc-alkaline magmas, which occurred widely in magmatic arcs worldwide. A widely accepted model is that such deposits were formed from hydrothermal fluids exsolved from hydrous, high oxygen fugacity, sulfur-rich arc magmas, derived from a mantle wedge metasomatized by subduction-slab fluids. Recent studies have documented that such deposits may also occur in post-collisional settings, e.g., the Gangdese porphyry Cu belts in Tibet. The formation of such PCDs is very difficult to be explained by the classic PCDs model, which results in an alternative model to be proposed to interpret the genesis of PCDs in such settings. In this alternative model, metals and sulfur of the post-collisional PCDs were generally thought to be derived from a subduction-modified thickened lower crust, rather than a metasomatized mantle wedge. However, our detailed analysis suggests that the sources of metals and sulfur for the PCDs in post-collisional settings still cannot be well explained by the lower-crust melting model. 展开更多
关键词 Where were the Metal Sulfur and water from in the Postcollisional Porphyry Cu deposit at Qulong in South Tibet CU
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Corrosion of Water Pipes: a Comprehensive Study of Deposits
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作者 Vikas Chawla Prema G. Gurbuxani G.R. Bhagure 《Journal of Minerals and Materials Characterization and Engineering》 2012年第5期479-492,共14页
Corrosion scales play an important role in modifying water quality in drinking water distribution systems. The corrosion scales from old water pipe lines were analyzed for their structure and composition. This paper p... Corrosion scales play an important role in modifying water quality in drinking water distribution systems. The corrosion scales from old water pipe lines were analyzed for their structure and composition. This paper presents the results of comprehensive study of deposits found in water distribution system of Ulhasnagar city of Maharashtra, India. Scales were investigated by XRD, FTIR, SEM and ED’s analytical techniques. It was found that goethite, magnetite, lepidocrocite, hematite and Akaganite were identified as the primary constituents of brown deposits. The corrosion scales had a shell-like, enveloping layer, covering porous deposits of iron oxide phases. Our studies were able to identify important constituents of three different pipes of water distribution systems. Akaganite was found to be present in chloride environment. Along with iron hydroxide phases it was found that corrosion product also contain some organic matter which may be due to adsorption of biofilm on the surface of pipe. Further studies are needed to establish the role of corrosion scales in the mechanism of iron release from corroded pipes. 展开更多
关键词 CORROSION water DISTRIBUTION system BROWN depositS IRON OXIDES bio-film.
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Deposition of water-soluble inorganic ions in PM_(2.5) in a typical forestry system in Beijing,China
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作者 Junqi Ding Xiaoxiu Lun +4 位作者 Weifang Ma Lu Zhao Yingying Cao Fengbin Sun Renna Li 《Forest Ecosystems》 SCIE CSCD 2018年第4期486-497,共12页
Background: Rapid economic development in China has resulted in an increase in severe air pollution in city groups such as the Beijing-Tianjin-Hebei Metropolitan Region. PM2.5(fine particles with an aerodynamic equiva... Background: Rapid economic development in China has resulted in an increase in severe air pollution in city groups such as the Beijing-Tianjin-Hebei Metropolitan Region. PM2.5(fine particles with an aerodynamic equivalent diameter of 2.5 μm or less) is one of the most important pollutants. The deposition process is an important way of removing particles from the air. To evaluate the effect of an urban forest on atmospheric particle removal, a concentration gradient method was used to measure the deposition velocities of water-soluble inorganics in PM2.5 in two national forest parks in Beijing, China. The following eight water-soluble inorganic ions in PM2.5 were investigated: sodium, ammonium, potassium, magnesium, calcium, chloride, nitrate, and sulfate.Methods: Samples were taken from two sites in Beijing from the 7 th to the 15 th May, 2013. The concentrations of water-soluble inorganic ions were analyzed with ion chromatography. We used the concentration gradient technique to estimate the deposition flux and velocity. To determine the relationships between leaf traits and particle accumulation, typical leaf samples from each selected species were studied using scanning electron microscopy.Results: The total deposition flux and total deposition velocity during the daytime were higher than those at night.Sulfate showed the biggest deposition flux and velocity at both study sites, whereas the other ions showed different trends at each site. Result from higher proportion of coniferous to broadleaved trees, the total deposition flux of the eight ions measured in Jiufeng National Forest Park was greater than that in Olympic Forest Park.Conclusions: The deposition velocity was affected by meteorological conditions such as wind speed, temperature,and humidity. The deposition velocity was also influenced by tree species. The surface of plants is an important factor influencing particle deposition. The results of this study may help in assessing the effects of forestry systems on particle removal and provide evidence for urban air pollution control and afforestation of urban areas. 展开更多
关键词 Fine particle water-soluble inorganics FOREST Dry deposition deposition velocity
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Friction Behaviors of the Hot Filament Chemical Vapor Deposition Diamond Film under Ambient Air and Water Lubricating Conditions 被引量:2
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作者 SHEN Bin SUN Fanghong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第5期658-664,共7页
The friction behavior of the hot filament chemical vapor deposition(HFCVD) diamond film plays a critical role on its applications in mechanical fields and largely depends on the environment. Studies on the tribologi... The friction behavior of the hot filament chemical vapor deposition(HFCVD) diamond film plays a critical role on its applications in mechanical fields and largely depends on the environment. Studies on the tribological properties of HFCVD diamond films coated on Co-cemented tungsten carbide (WC-Co) substrates are rarely reported in available literatures, especially in the water lubricating conditions. In this paper, conventional microcrystalline diamond(MCD) and fine-grained diamond(FGD) films are deposited on WC-Co substrates and their friction properties are evaluated on a reciprocating ball-on-plate tribometer, where they are brought to slide against ball-bearing steel and copper balls in dry and water lubricating conditions. Scanning electron microscopy(SEM), atomic force microscopy(AFM), surface profilometer and Raman spectroscopy are adopted to characterize as-deposited diamond films; SEM and energy dispersive X-ray(EDX) are used to investigate the worn region on the surfaces of both counterface balls and diamond films. The research results show that the friction coefficient of HFCVD diamond films always starts with a high initial value, and then gradually transits to a relative stable state. For a given counterface and a sliding condition, the FGD film presents lower stable friction coefficients by 0.02-0.03 than MCD film. The transferred materials adhered on sliding interface are supposed to have predominate effect on the friction behaviors of HFCVD diamond films. Furthermore, the effect of water lubricating on reducing friction coefficient is significant. For a given counterpart, the stable friction coefficients of MCD or FGD films reduce by about 0.07-0.08 while sliding in the water lubricating condition, relative to in dry sliding condition. This study is beneficial for widespread applications of HFCVD diamond coated mechanical components and adopting water lubricating system, replacing ofoil lubricating, in a variety of mechanical processing fields to implement the green production process. 展开更多
关键词 Hot filament chemical vapor deposition(HFCVD) diamond films friction behavior water lubricating
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