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Optical Modeling of Sea Salt Aerosols Using in situ Measured Size Distributions and the Impact of Larger Size Particles
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作者 Wushao LIN Lei BI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第10期1917-1935,共19页
Sea salt aerosols play a critical role in regulating the global climate through their interactions with solar radiation.The size distribution of these particles is crucial in determining their bulk optical properties.... Sea salt aerosols play a critical role in regulating the global climate through their interactions with solar radiation.The size distribution of these particles is crucial in determining their bulk optical properties.In this study,we analyzed in situ measured size distributions of sea salt aerosols from four field campaigns and used multi-mode lognormal size distributions to fit the data.We employed super-spheroids and coated super-spheroids to account for the particles’non-sphericity,inhomogeneity,and hysteresis effect during the deliquescence and crystallization processes.To compute the singlescattering properties of sea salt aerosols,we used the state-of-the-art invariant imbedding T-matrix method,which allows us to obtain accurate optical properties for sea salt aerosols with a maximum volume-equivalent diameter of 12μm at a wavelength of 532 nm.Our results demonstrated that the particle models developed in this study were successful in replicating both the measured depolarization and lidar ratios at various relative humidity(RH)levels.Importantly,we observed that large-size particles with diameters larger than 4μm had a substantial impact on the optical properties of sea salt aerosols,which has not been accounted for in previous studies.Specifically,excluding particles with diameters larger than 4μm led to underestimating the scattering and backscattering coefficients by 27%−38%and 43%−60%,respectively,for the ACE-Asia field campaign.Additionally,the depolarization ratios were underestimated by 0.15 within the 50%−70%RH range.These findings emphasize the necessity of considering large particle sizes for optical modeling of sea salt aerosols. 展开更多
关键词 sea salt aerosol particle size distribution LIDAR optical property
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Simulation of the Direct Radiative Effect of Mineral Dust and Sea Salt Aerosols in a Doubled Carbon Dioxide Climate 被引量:2
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作者 YUE Xu LIAO Hong TANG Jin-Ping 《Atmospheric and Oceanic Science Letters》 CSCD 2013年第5期343-348,共6页
The authors examine the equilibrium climatic response to the direct radiative effect (DRE) of mineral dust and sea salt aerosols in a doubled-CO2 climate with two-way coupling of aerosol-climate interactions.In resp... The authors examine the equilibrium climatic response to the direct radiative effect (DRE) of mineral dust and sea salt aerosols in a doubled-CO2 climate with two-way coupling of aerosol-climate interactions.In response to the drier and windier conditions,dust emissions increase by 26% in the Sahara Desert and by 18% on the global scale relative to present day.Sea salt emissions increase in high latitudes (>60°) but decrease in middle latitudes (30°-60°) of both hemispheres due to the poleward shift of westerlies,leading to a 3% decrease in global emissions.The burdens of dust and sea salt increase by 31% and 7% respectively,because reductions in rainfall over the tropical oceans increase the lifetime of particles in the warmer climate.The higher aerosol loading in the doubled-CO2 climate reinforces aerosol DRE by -0.2 W m-2,leading to an additional cooling of 0.1℃ at the surface compared with the climatic effects of aerosols in present day.The additional cooling from changes in natural aerosols compensates for up to 15% of the regional warming induced by doubled CO2. 展开更多
关键词 mineral dust sea salt aerosol direct radiative effect
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The concentration variation features of sea salt ions and non sea salt ions in a firn core recovered from Princess Elizabeth Land, East Antarctica
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作者 张明军 任贾文 +2 位作者 效存德 李忠勤 秦大河 《Chinese Journal of Polar Science》 2004年第2期85-90,共6页
A 51.85 m firn core drilled in Princess Elizabeth Land, Antarctica, during the 1996-1997 Chinese First Antarctic Inland Expedition, has been measured for δ 18 O and major ions. Based on the high quality data ... A 51.85 m firn core drilled in Princess Elizabeth Land, Antarctica, during the 1996-1997 Chinese First Antarctic Inland Expedition, has been measured for δ 18 O and major ions. Based on the high quality data of the seasonal variations of major ions, the firn core was dated with errors within ±3 years. The 51.85 m firn core record extends for 251 years (A. D. 1745-1996). The results of the glaciochemistry data of the firn core show that the mean concentrations of Cl -, Na + and Mg 2+ are similar to those reported from other coastal areas in East Antarctica. However, mean concentrations of Ca 2+ are much higher than those reported from other regions, this anomaly phenomenon may be related to the strong local terrestrial sources. It is found that the variations of three kinds of sea salt ions (Cl -, Na + and Mg 2+ ) in the past 150 years show very similarly rising trends, which may be the results the Southern Hemisphere warming in the past century. 展开更多
关键词 ANTARCTICA firn core sea salt ion and non sea salt ion.
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High Contribution of Sea Salt Aerosols on Atmospheric Particles Measured at an Urban Tropical Location in Reunion Island
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作者 Chatrapatty Bhugwant Miloud Bessafi +3 位作者 Olivier Favez Laura Chiappini Bruno Sieja Eva Leoz-Garziandia 《Journal of Environmental Protection》 2013年第8期828-842,共15页
PM10 was monitored during 2008-2011 period at LUT and BON, two urban tropical stations close to each other at Saint-Pierre city, in Reunion Island (south-western Indian Ocean). During the study period, notable PM10 co... PM10 was monitored during 2008-2011 period at LUT and BON, two urban tropical stations close to each other at Saint-Pierre city, in Reunion Island (south-western Indian Ocean). During the study period, notable PM10 concentrations are observed at BON close to the coasts. At LUT, a more inland site, the daily PM10 concentration range between 13 and 70 μg/m3. Importantly, the limit value for the protection of the human health is systematically exceeded at BON while it is never exceeded at LUT. Also, the quality objective (QO: 30 μg/m3, on annual average) and the limit value for the human health protection (LV: 40 μg/m3, on annual average) are exceeded at BON each year during 2008-2011, while at LUT no regulatory values are exceeded. Nitrogen dioxide, an atmospheric tracer of anthropogenic activities was also monitored at LUT and BON. The mean diurnal NO2 variation is of the same level and order of magnitude and exhibits a similar pattern at both stations suggesting that distinct sources influence the PM10 at LUT and at BON. Chemical analysis was performed on daily filters sampled in September-November 2011 at the two stations to determine the sea salt contribution on PM10 across Saint-Pierre city. It showed that the sea salt contribution to the PM10 is 55% at BON in September 2011. The sea salt particles are therefore the main cause for the exceedances of the regulatory values of PM10 recorded at BON. The results importantly suggest that the notable PM10 concentrations measured at this urban marine site might have some but minor impact on human health. 展开更多
关键词 PM10 Nitrogen Dioxide ANTHROPOGENIC sea salt AEROSOLS Chemical Characterization REGULATORY Values Human Health Lung Cancer URBAN TROPICAL
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Heterogeneous reactions of gaseous methanesulfonic acid with NaCl and sea salt particles 被引量:7
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作者 TANG MingJin ZHU Tong 《Science China Chemistry》 SCIE EI CAS 2009年第1期93-100,共8页
Methanesulfonic acid(MSA) has been identified as one of the most important intermediate products of DMS reactions in the atmosphere.Although considerable amounts of MSA have been found in the ma-rine boundary layer,li... Methanesulfonic acid(MSA) has been identified as one of the most important intermediate products of DMS reactions in the atmosphere.Although considerable amounts of MSA have been found in the ma-rine boundary layer,little is known about the interaction of gaseous MSA with sea salt particles.To understand the fate of MSA in the atmosphere and its potential importance in atmospheric chemistry,the heterogeneous reactions of gaseous MSA with micron-scale NaCl and sea salt particles were studied using diffuse reflectance infrared Fourier transform spectrometry,X-ray photoelectron spectroscopy,and scanning electron microscopy.The CH3SO3Na and CH3SO3-were the major products of the condensed phase of the reaction of gaseous MSA with NaCl and with sea salt particles.The steady-state uptake coefficient was determined to be(5.94±2.32)×10-7(1 σ) for the reaction of gaseous MSA with NaCl particles and(2.23±1.25)×10-7(1 σ) for the reaction of gaseous MSA with sea salt parti-cles.The heterogeneous reaction of MSA with NaCl particles was found to be first-order for MSA.The reaction mechanisms were discussed. 展开更多
关键词 methanesulfonic ACID HETEROGENEOUS reaction NACL sea salt
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Characteristics analysis and model prediction of sea-salt water intrusion in lower reaches of the Weihe River,Shandong Province,China 被引量:5
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作者 WANG Ji-ning MENG Yong-hui 《Journal of Groundwater Science and Engineering》 2016年第2期149-156,共8页
Marine sedimentary strata are widely distributed in the coastal zone of the study area, and are rich in brine resources. The exploitation of underground water resources often first caused the intrusion of salt water i... Marine sedimentary strata are widely distributed in the coastal zone of the study area, and are rich in brine resources. The exploitation of underground water resources often first caused the intrusion of salt water in the marine strata. Based on the analysis of sea-salt water intrusion feature, the sea-salt water intrusion is divided into four stages: The occurrence and development stage(1976–1985), the rapid development stage(1986–1990), the slow development stage(1990–2000) and the stable development stage(2000–2015). Based on the comparative analysis of the relationship between seawater intrusion and influencing factors, this paper presents that the groundwater exploitation and the brine resources mining are the main control factors of sea-salt water intrusion. On this basis, we have established a numerical model of the sea-salt water intrusion. Using this model, we predicted the development trend of the sea-salt water intrusion. The results show that if the current development of groundwater and brine is maintained, the sea-salt water intrusion will gradually withdraw; once development of brine stops, sea-salt water will invade again. This provides the scientific basis for the rational exploitation of groundwater and the prevention of sea-salt water intrusion. 展开更多
关键词 sea-salt water intrusion Marine sedimentary strata Brine resources Numerical simulation Influencing factors
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Non-sea-salt sulfate in the marine boundary layer and its possible impact on chloride depletion 被引量:1
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作者 Cole-Dai Jihong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2005年第6期162-171,共10页
Aerosol samples were collected on board the research vessel Xuelong duringthe Fifteenth Chinese Antarctic Research Expedition (CHINARE XV) in November 1998—April 1999 andthe First Chinese Arctic Research Expedition i... Aerosol samples were collected on board the research vessel Xuelong duringthe Fifteenth Chinese Antarctic Research Expedition (CHINARE XV) in November 1998—April 1999 andthe First Chinese Arctic Research Expedition in July—September 1999.The areas traversed by theexpeditionary cruises include the Arctic Ocean, the western North Pacific Ocean and the easternIndian Ocean, covering 75°N—69°S and 75°E—133°W. Aerosol samples were also taken at theChinese Zhongshan Station in East Antarctica during the CHINARE XV. Analysis of the samples yieldedconcentrations of non-sea-salt sulfate and other soluble chemical species in the marine boundarylayer. The data suggest that the chemical composition of the marine aerosols is influenced by threemajor sources: continental air masses, primary oceanic emissions, and secondary marine aerosolsoriginated from oceanic emissions.The results show that, awing to strong anthropogenic sulfuremissions from the Asian continent, non-sea-salt sulfate concentrations in the Northern Hemisphere(the western North Pacific) marine aerosol are significantly higher than those in the SouthernHemisphere (the eastern Indian Ocean). Aerosol non-sea-salt sulfate concentrations appear to beinversely correlated with aerosol non-sea-salt chloride which shows significantly negative values,indicating the loss of chloride by sea salts, in most aerosol samples. Since gaseous HCl may beinvolved in chemical reactions that deplete atmospheric ozone in the marine boundary layer (MBL),high levels of acidic non-sea-salt-sulfate released by human activities in the low and mid-latitudesof the Northern Hemisphere may become an important potential contributor to the loss of atmosphericozone in the MBL. 展开更多
关键词 non-sea-salt sulfate marine boundary layer chloride depletion
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Heterogeneous reaction of NO_2 with sea salt particles 被引量:1
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作者 YE ChunXiang 1,LI HongJun 1,ZHU Tong 1,SHANG Jing 1,ZHANG ZeFeng 1,2 & ZHAO DeFeng 1 1 State Key Joint Laboratory of Environmental Simulation and Pollution Control College of Environmental Sciences and Engineering,Peking University,Beijing 100871,China 2 College of Atmospheric Physics,Nanjing University of Information Science and Technology,Nanjing 210044,China 《Science China Chemistry》 SCIE EI CAS 2010年第12期2652-2656,共5页
To understand how NO2 reacts with sea salt particles in the atmosphere of Mega-cities in coastal zones,the heterogeneous reaction of NO2 on the surface of wet sea salt was investigated with diffuse reflectance infrare... To understand how NO2 reacts with sea salt particles in the atmosphere of Mega-cities in coastal zones,the heterogeneous reaction of NO2 on the surface of wet sea salt was investigated with diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and ion chromatography (IC).Kinetic measurements indicated that nitrate formation on sea salt was second order in NO 2 concentration and reactive uptake coefficients were (5.51 ± 0.19) × 10-7 and 1.26 × 10-6 respectively under 0% and 20% relative humidity (RH) at NO 2 molecular concentration of 1.96 × 1015 mol/cm3.The results showed that liquid water was formed at the site of MgCl2·6H2O,CaCl2·2H2O on the surface of sea salt and made the reaction more sustainable by releasing hydrated water and absorbing water from air even under a low RH (30%).Therefore,pure NaCl particles should not be used to represent sea salt in studies of the heterogeneous reaction with NO2. 展开更多
关键词 sea salt PARTICLES DIFFUSE reflectance infrared FOURIER transform spectroscopy (DRIFTS) hydrated WATER absorbed WATER reactive UPTAKE coefficient
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DISTRIBUTION FEATURES OF GIANT SEA-SALT NUCLEI IN ATMOSPHERE OVER YONGXING ISLAND, XISHA ISLANDS,DURING NORTHEAST WINTER MONSOON
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作者 吴兑 游积平 关越坚 《Journal of Tropical Meteorology》 SCIE 1996年第2期216-221,共6页
In this paper, the chlorine ions nuclei data, observed at Yongxing (Xisha Islands ) during November 1987, are analyzed. The main results are: 1) The average concentration of chiorine ions nuclei with dry diameters la... In this paper, the chlorine ions nuclei data, observed at Yongxing (Xisha Islands ) during November 1987, are analyzed. The main results are: 1) The average concentration of chiorine ions nuclei with dry diameters larger than 2 μm is 878 per litre and the average salt content is 105. 4μg/m3, in which special giant nuclei with dry diameters larger than 4 μm are 19O per litre. The largest dry diameter of chloride ions observed reaches 57 μm, which are larger than that observed there during the southwest summer monsoon. The spetrum type shows quasi-unimodal and exponential lapse. 2) The salt content decreases with the height over sea surface. 3) The concentrations of chlorine ions nuclei reach the maximum value at 0800 (Local time, same below ). and minimum at 0200. 展开更多
关键词 GIANT sea-salt nucleus salt content spectrum DISTRIBUTION
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Seasonal variations in aerosol compositions at Great Wall Station in Antarctica 被引量:1
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作者 ZHANG Yuanhui WANG Yanmin +6 位作者 ZHANG Miming CHEN Liqi LIN Qi YAN Jinpei LI Wei LIN Hongmei ZHAO Shuhui 《Advances in Polar Science》 2015年第3期196-202,共7页
High volume aerosol samplers at Great Wall Station in Antarctica were used to collect 73 aerosol samples between January 2012 and November 2013. The main ions in these aerosol samples, Cl^-, NO3-, SO4^2-, Na+, K+, ... High volume aerosol samplers at Great Wall Station in Antarctica were used to collect 73 aerosol samples between January 2012 and November 2013. The main ions in these aerosol samples, Cl^-, NO3-, SO4^2-, Na+, K+, Ca2+, Mg2+, NH4+, as well as methane sulfonic acid, were analyzed using ion chromatography. Trace metals in these samples, including Pb, Cu, Cd, V, Zn, Fe, and Al, were determined by inductively-coupled plasma mass spectrometry. Results showed that sea salt was the main component in aerosols at Great Wall Station. Most ions exhibited significant seasonal variations, with higher concentrations in summer and autumn than in winter and spring. Variations in ions and trace metals were related to several processes(or sources), including sea salt emission, secondary aerosol formation, and anthropogenic pollution from both local and distant sources. The sources of ions and trace metals were identified using enrichment factor, correlation, and factor analyses. Clearly, Na+, K+, Ca2+, and Mg2+were from marine sources, while Cu, Pb, Zn, and Cd were from anthropogenic pollution, and Al and V were mainly from crustal sources. 展开更多
关键词 ANTARCTICA Great Wall Station AEROSOLS IONS trace metals sea salt seasonal variation POLLUTION longrange transport
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Remote sensing of trace Na element in sea salt aerosol with a sensitivity level of 10 pg/m^(3)[Invited]
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作者 Yuezheng Wang Jiayun Xue +7 位作者 Nan Zhang Lu Sun Binpeng Shang Jiewei Guo Zhi Zhang Pengfei Qi Lie Lin Weiwei Liu 《Chinese Optics Letters》 SCIE EI CAS 2024年第9期26-30,共5页
We have developed a remote sea salt aerosol fluorescence spectroscopy system integrating a high-power industrial-grade femtosecond laser to enhance detection sensitivity and precision in complex environments.This syst... We have developed a remote sea salt aerosol fluorescence spectroscopy system integrating a high-power industrial-grade femtosecond laser to enhance detection sensitivity and precision in complex environments.This system successfully detects sea salt aerosol particles,achieving a detection limit of 0.015 ng/m^(3) for neutral Na element(Na I)at 589 nm,with a detection range of 30 m.Our findings demonstrate significant improvements in remote aerosol monitoring,addressing previous challenges in long-range and high-precision sensing with a detection accuracy previously unattainable below 10 ng/m^(3). 展开更多
关键词 femtosecond laser filamentation sea salt aerosol remote sensing amplified spontaneous emission
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CMAS、CMAS+NaVO_(3)、CMAS+海盐作用下热障涂层的腐蚀行为与机理 被引量:2
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作者 郭磊 张馨木 杨硕 《中国表面工程》 EI CAS CSCD 北大核心 2024年第1期75-86,共12页
环境沉积物(CaO-MgO-Al_(2)O_(3)-SiO_(2),CMAS)的高温腐蚀已成为航空发动机涡轮叶片热障涂层过早失效的重要原因之一。然而涡轮叶片工作环境复杂,熔盐、海盐常与CMAS耦合,一起对热障涂层造成多元复杂腐蚀,但目前关于CMAS与盐类的多元... 环境沉积物(CaO-MgO-Al_(2)O_(3)-SiO_(2),CMAS)的高温腐蚀已成为航空发动机涡轮叶片热障涂层过早失效的重要原因之一。然而涡轮叶片工作环境复杂,熔盐、海盐常与CMAS耦合,一起对热障涂层造成多元复杂腐蚀,但目前关于CMAS与盐类的多元耦合腐蚀行为鲜有报道。针对Y2O_(3)部分稳定ZrO_(2)(YSZ)热障涂层在CMAS、CMAS+NaVO_(3)、CMAS+海盐作用下的腐蚀行为进行对比研究。通过XRD、SEM等方法对不同条件下腐蚀后的涂层进行表征,并分析热处理温度、腐蚀物种类对腐蚀行为的影响。结果表明:与CMAS相比,CMAS+NaVO_(3)、CMAS+海盐会在更低的温度下损伤涂层(1200℃)。当三种腐蚀物均能完全熔化时(1250℃),CMAS+NaVO_(3)、CMAS+海盐熔体则由于更大的流动性而大量渗入,腐蚀内部涂层。其中,CMAS+海盐熔体在涂层内的渗透性最强,1250℃热处理4 h后,渗透深度超过400μm。盐类的共存会改变CMAS的性质,增强熔体的渗透能力,增加涂层内部甚至底部失效的倾向。研究结果有助于理解盐类与CMAS耦合时混合熔体对热障涂层的破坏机理及潜在威胁。 展开更多
关键词 热障涂层 CMAS+海盐 CMAS+NaVO_(3) 耦合腐蚀 腐蚀机理
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Primary Production and the Hydrochemical Parameters of the Salt Lakes in the North-Western Part of the Crimea(Russia)
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作者 Vladimir POPOVICHEV Oleg EREMIN +2 位作者 Natalya RODIONOVA Tatyana TSARINA Nikolai BOBKO 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期96-97,共2页
1 Introduction It is known that more than 300 lakes and lagoons are present in the Crimean Peninsula,which are divided depending on position to 7 groups:Perekop,Tarkhankut,Evpatoriyskaya,Khersonesskaya,lake on the mou... 1 Introduction It is known that more than 300 lakes and lagoons are present in the Crimean Peninsula,which are divided depending on position to 7 groups:Perekop,Tarkhankut,Evpatoriyskaya,Khersonesskaya,lake on the mountainpastures,Kerch and Genicheskaya.Almost the all lakes,with the exception of the small freshwater lakes,which situated on mountain pastures of the Main ridge of 展开更多
关键词 the Black sea the Crimea salt lakes hydrochemical parameters of salt water primary production
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Petroleum Exploration in the Yemeni Red Sea and Offshore Area (Tihama Basin)
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作者 ENG Mohammed Al Zubairi (College of Geo-Exploration and Information Technology, Jilin University, Changchun, 130026, P.R.China) 《Global Geology》 2001年第2期162-168,共7页
The Red Sea is a pericratonic upper Tertiary basin which developed on the continental margin of Arabia. It is characterized by halokinetic tectonics in the upper structural stage and block-Rifting in the lower structu... The Red Sea is a pericratonic upper Tertiary basin which developed on the continental margin of Arabia. It is characterized by halokinetic tectonics in the upper structural stage and block-Rifting in the lower structural stage. This margin is overprinted on a Pre-rift Mesozoic platform. Hydrocarbon exploration interest in the Yemeni Red Sea sector and Offshore area (Tihama Basin) is based on three objectives, which cross pond to stages in geotectonic evolution; Mesozoic Pre-rift targets; Miocene Syn-Rift Salt targets; and upper Miocene-Pliocene Post-rift drift sequences. Reservoirs with appropriate sealing units ( salt or shale ) have been recorded. Models of source rock maturation using observed geothermal gradients are consistent with analytical results, and prove of oil and gas generation. Most traps are described as faulted, fault-blocks, listric-faults or structural. The evaporite group mainly consists of Halite and Anhydrite, that exhibits a strong halokinesis affecting a structural style-of Infra and Intra evaporite sequences in offshore (Tihama basin ). 展开更多
关键词 Yemeni RED sea Mobil salt and Halokinetic
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A method for estimating the fresh water-salt water interface with hydraulic heads in a coastal aquifer and its application
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作者 Xun Zhou 《Geoscience Frontiers》 SCIE CAS 2011年第2期199-203,共5页
Examining the descriptions of piezometric heads at two points in both the salt water and fresh water zones reveals that when the groundwater flow system is in steady state and satisfies the Dupuit assumption, the loca... Examining the descriptions of piezometric heads at two points in both the salt water and fresh water zones reveals that when the groundwater flow system is in steady state and satisfies the Dupuit assumption, the location of the fresh water-salt water interface in a homogeneous, isotropic, and unconfined coastal aquifer can be estimated based on a piezometric head of fresh water at a point in the fresh water zone (from the water table to the interface) vertically lined up with a piezometric head of salt water at a point in the salt water zone (from the interface down). Research shows that the new method is a general relation and that both the Hubbert relation describing the location of the interface and the Ghy- ben--Herzberg relation are special cases of this method. The method requires two piezometric wells to be close to each other and each tapping into a different zone. Measurements of piezometric heads at a well cluster consisting of piezometric wells tapping separately into fresh water and salt water zones near Beihai, China at 5-day intervals for 15 months are used to illustrate the estimation of interface location. The depth of the interface for well H5 ranges from 32 to 72 m below the sea level. 展开更多
关键词 Fresh water-salt waterinterface sea water intrusion Tidal effect Coastal aquifer
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官控层级作用下海盐聚落体系演变研究——以明清两淮盐区为例
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作者 张晓莉 赵逵 《城市规划》 CSSCI CSCD 北大核心 2024年第3期115-122,共8页
梳理明清海盐产区官控层级由“分司-盐场-团”向“分司-盐场-灶”发展过程中各层级职能的变化,建立与官控层级对应的“分司-场治-团”和“分司-场治-市镇-生产”的聚落发展体系。从时间纵向的角度,立足官控层级重心迁移,结合经济、自然... 梳理明清海盐产区官控层级由“分司-盐场-团”向“分司-盐场-灶”发展过程中各层级职能的变化,建立与官控层级对应的“分司-场治-团”和“分司-场治-市镇-生产”的聚落发展体系。从时间纵向的角度,立足官控层级重心迁移,结合经济、自然、文化等因素的变化,解析海盐聚落体系整体格局的纵横发展,总结聚落体系层级格局分布的演变规律。立足官控层级职能变迁,结合明清海盐聚落体系空间构成要素的量化分析,对海盐聚落体系层级空间形态的演变规律进行总结。研究现代东部沿海聚落体系的由来和发展过程,并为后续古代海盐手工业聚落体系的全面构建奠定基础。 展开更多
关键词 官控层级 海盐聚落体系演变 格局分布 空间形态 空间构成要素
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Evaluation of the Quality for the Egyptian Red Sea Coastal Waters during 2011-2013 被引量:2
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作者 Mamdouh A. Fahmy Laila M. Abdel Fattah +7 位作者 Ahmed M. Abdel-Halim Mohamed A. Aly-Eldeen Ehssan M. Abo-El-Khair Hoda H. Ahdy Hoda H. Ahdy Ahmed Hemeilly Ahmed Abu El-Soud Mohamed A. Shreadah 《Journal of Environmental Protection》 2016年第12期1810-1834,共25页
To assess the quality of the Egyptian Red Sea coastal waters for the sustainable use and development, due to its importance for the national income, four field campaigns were annually carried out during the period fro... To assess the quality of the Egyptian Red Sea coastal waters for the sustainable use and development, due to its importance for the national income, four field campaigns were annually carried out during the period from 2011-2013 to investigate the hydrography, nutrient salts, heavy metals and petroleum hydrocarbons. Except for the area of Bir Shalatein, the results of beach litter cleared out that the shoreline of the studied area is not affected by man-made litter. No sewage could be observed. The results of the present study showed that water temperature followed seasonal changes in air temperature. Red Sea water is more saline than adjacent Arabian Sea. DO revealed high values and presence of well oxygenated waters. Minor changes in the distribution of pH, BOD, DOM and COD, revealed that limited effects of human impacts and depend mainly on the dynamics of its water as well as on the geographical location. Low Chl-a and TSM concentrations and high transparency revealed that also the effect of human impacts is almost negligible. Significantly higher sea water temperatures, TSM, pH, DO, BOD, DOM, and COD were observed in summer season compared to their corresponding values in winter season. Dissolved inorganic nitrogen concentrations were quite low because there is little nutrient input from soil, agriculture and pollution on land. Based on the annual mean values, the pattern concentrations of dissolved inorganic nitrogen forms followed the order: NO<sub>3</sub> > NH<sub>4</sub> > NO<sub>2</sub>. The Red Sea coastal waters are classified as oligotrophic to mesotrophic state. A remarkable increase of PO<sub>4</sub> concentration was observed in the middle Red Sea stations due to huge amounts of effluents enriched with phosphate from the main shipping and industry of Phosphate Companies. SiO<sub>4</sub> displayed a large variability due to the supply of SiO<sub>4</sub>, which flows in the Red Sea through the strait of Bab El-Mandab, biological consumption, organic matter decomposition and the partial dissolution of quartz particle transported to the sea from the surrounding desert during sand storms. Concentrations of ammonia, phosphorus, total nitrogen, and total phosphorus were significantly higher in summer compared to their corresponding values in winter. In general, the majority of TN and TP in winter were in the form of organic-N (91.3%) and organic P (96.8%). The mean DIN/DIP ratio revealed high nitrogen concentrations in comparison with that of phosphorous and the surface coastal waters of the Red Sea are principally, P-limited for phytoplankton growth with higher values in winter season compared to summer season. Concentrations of heavy metals were quite low most probably due the absence of major local impacts of any land-based sources and/or any major negative impacts of coastal tourism. Regional variations were almost negligible and except for Mn, Cd, and Hg insignificant seasonal variations were observed. The present study revealed concentrations for metals in the acceptable levels. Furthermore, concentrations of petroleum hydrocarbons were significantly higher in winter than in summer which is mainly attributed to the increase in the rate of evaporation for petroleum hydrocarbons in summer. In general, the maximum concentration was much lower than the harmful concentrations reported for seawater. Correlation coefficients as well as principle component analysis (PCA) were applied. 展开更多
关键词 Hydrography Nutrient salts Heavy Metals Petroleum Hydrocarbons Coastal Water Red sea
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Economic value and exploiting approaches of sea asparagus, a seawater-irrigated vegetable 被引量:1
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作者 Litian Feng Bin Ji Bin Su 《Agricultural Sciences》 2013年第9期40-44,共5页
Sea asparagus is a newly emerging seawater-irrigated vegetable. Firstly, the economic value of sea asparagus was introduced, and then, someexploiting approaches of sea asparagus werefully reviewed. The exploiting appr... Sea asparagus is a newly emerging seawater-irrigated vegetable. Firstly, the economic value of sea asparagus was introduced, and then, someexploiting approaches of sea asparagus werefully reviewed. The exploiting approaches mainly include fresh vegetable, pickle, bio-salt, health-care products, animal feed, vegetable oil, bio-diesel and skin-care products. 展开更多
关键词 sea ASPARAGUS seawater-Irrigated VEGETABLE ECONOMIC Value Exploiting APPROACHES Bio-salt
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Radiochemoecological Monitoring of the Salt Lakes of the Crimea
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作者 Natalya MIRZOYEVA Sergey GULIN +4 位作者 Olga PLOTITSINA Alexandra STETSUK Svetlana ARKHIPOVA Nina KORKISHKO Oleg EREMIN 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期155-157,共3页
1 Introduction The salt lakes of the Crimea contain the practically inexhaustible sources of salts of sodium,magnesium,bromine and other chemical elements(Ponizovskii,1965),being the potential powerful raw materials b... 1 Introduction The salt lakes of the Crimea contain the practically inexhaustible sources of salts of sodium,magnesium,bromine and other chemical elements(Ponizovskii,1965),being the potential powerful raw materials base for the 展开更多
关键词 the Crimea salt lakes the Black sea the Chernobyl NPP accident water SEDIMENTS HYDROBIONTS Hg 90Sr ecological impact.
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FORECAST OF IMPACTS OF SEA-LEVEL RISE ON THELOW COLONIZED ISLANDS AND THEIR SURROUNDING WATERS IN THE CHANGJIANG RIVER MOUTH
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作者 YANG Shi-lun ZHAO Qing-ying +1 位作者 XIE Wen-hui WANG Xing-fang(State Key Laboratory of Estuarine & Coastal Research, East China Normal University, Shanghai 200062, P R. China) 《Chinese Geographical Science》 SCIE CSCD 2000年第2期113-118,共6页
As a worldwide authoritative, IPCC forecasted in 1990 that the world- s sea level would most probably rise by 0. 66 m by the end of the 21 st century. Combined with the local depression caused by the sink of the earth... As a worldwide authoritative, IPCC forecasted in 1990 that the world- s sea level would most probably rise by 0. 66 m by the end of the 21 st century. Combined with the local depression caused by the sink of the earth’s crust and the human activity, the relative sea level in the Chanaiiang River mouth will rise by about 1. 0 m during the same peried. Based on this figure, the article forecasted the impacts of sea-level rise on the safety coefficient of coastal structures and civil facilities, loss of wetlands, flood hazard as well as water intrusion. The results show that: 1 ) 40% as large as the present engil1eering mass should be added to the coastal structures in order to maintain the safety coefficient; 2 ) a dynamic loss of 60 km2 of wetlands, as much as 15% of the present total area, would be caused; 3) to hinder the increase inflood hazard dy11amic capacity to drain water must increase by at least 34 times as large as the present; 4) to maintain the present navigation conditions, about 100 million yuan (RMB) is needed to reconstruct over 30(X) bridges and 30 sluices;and 5 ) the disastrous salt water intrusion caused by the sea-level rise could be encountered by the increase in water discharge from the Three Gorge Reservoir in the dry season. 展开更多
关键词 sea-LEVEL rise flood hazard loss of wetland salt water INTRUSION CHANGJIANG River MOUTH
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