992 resultados para FRESH EXTRACTION SITES


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While the input of river-alkalinity into seawater is relatively well known, the complementary acidity production is poorly understood. Using the major-element budget of seafloor alteration of the upper 500 m of 120-Ma-old oceanic crust at DSDP/ODP Sites 417A, 417D and 418A in the central western Atlantic, we estimate the acidity flux associated with the low-temperature weathering of the upper oceanic crust. The acidity flux is calculated based on major-element fluxes and charge-balance considerations. The relevant chemical fluxes from seawater to the upper crust are 4.1+-0.1; 1.4+-1.4; 2.2+-0.6 and -12+-2 10**11 mol/yr for K, Mg, Na and silicate-Ca, respectively. The associated acidity flux is (3.5+-3)10**11 eq/y. Relative to continental weathering, these fluxes are significant for K and silicate-Ca, but are minor for Na, Mg and acidity. Thus, riverine fluxes of alkalinity are not significantly balanced by acidity fluxes from low-temperature upper ocean crust alteration.

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Many (bio)geochemical processes that bring about changes in sediment chemistry normally begin at the sediment-water interface, continue at depth within the sediment column and may persist throughout the lifetime of sediments. Because of the differential reactivity of sedimentary phosphate phases in response to diagenesis, dissolution/precipitation and biological cycling, the oxygen isotope ratios of phosphate (d18OP) can carry a distinct signature of these processes, as well as inform on the origin of specific P phases. Here, we present results of sequential sediment extraction (SEDEX) analyses combined with d18OP measurements, aimed at characterizing authigenic and detrital phosphate phases in continental margin sediments from three sites (Sites 1227, 1228 and 1229) along the Peru Margin collected during ODP Leg 201. Our results show that the amount of P in different reservoirs varies significantly in the upper 50 m of the sediment column, but with a consistent pattern, for example, detrital P is highest in siliciclastic-rich layers. The d18OP values of authigenic phosphate vary between 20.2 per mil and 24.8 per mil and can be classified into at least two major groups: authigenic phosphate precipitated at/near the sediment-water interface in equilibrium with paleo-water oxygen isotope ratios (d18Ow) and temperature, and phosphate derived from hydrolysis of organic matter (Porg) with subsequent incomplete to complete re-equlibration and precipitated deeper in the sediments column. The d18OP values of detrital phosphate, which vary from 7.7-15.4 per mil, suggest two possible terrigenous sources and their mixtures in different proportions: phosphate from igneous/metamorphic rocks and phosphate precipitated in source regions in equilibrium with d18Ow of meteoric water. More importantly, original isotopic compositions of at least one phase of authigenic phosphates and all detrital phosphates are not altered by diagenesis and other biogeochemical changes within the sediment column. These findings help to understand the origin and provenance of P phases and paleoenvironmental conditions at/near the sediment-water interface, and to infer post-depositional activities within the sediment column.

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Pore water was collected from each of 10 sites during Ocean Drilling Program (ODP) Leg 168 on the eastern flank of the Juan de Fuca Ridge. These ten sites delineate a transect perpendicular to the present ridge axis and span a crustal age of 0.86-3.59 Ma. At nine of the ten sites the entire sediment section, which ranged from 41.3 to 613.8 m thick, was cored and attempts were made to recover at least one whole round of sediment per section of core for extraction of pore water. Several (2-5) whole-round sediment samples were taken from the uppermost and lowermost cores to constrain the chemical gradient near the sediment/water and sediment/basalt interfaces, respectively. Pore water was extracted from whole-round sediment core sections by squeezing only the most pristine sediment in a titanium squeezer designed by Manheim and Sayles (1974). Two additional water samples were collected in situ using the water-sampler temperature probe (WSTP; Barnes, 1988, doi:10.2973/odp.proc.ir.110.104.1988). Both of these samples were collected in the cased section of the open borehole from ODP Hole 1026B. Formation fluids were flowing up the cased hole into the overlying deep seawater (Fisher et al., 1997, doi:10.1029/97GL01286). Detailed descriptions of the sampling methods that were used to collect fluids are given by the Shipboard Scientific Party (Davis, Fisher, Firth, et al., 1997, doi:10.2973/odp.proc.ir.168.1997).

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"EPA/540/AR-92/079."

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The ability of Escherichia coli to express the K88 fimbrial adhesin was satisfactorily indicated by the combined techniques of ELISA, haemagglutination and latex agglutination. Detection of expression by electron microscopy and the ability to metabolize raffinose were unsuitable. Quantitative expression of the K88 adhesin was determined by ELISA. Expression was found to vary according to the E.coli strain examined, media type and form. In general it was found that the total amount was greater, while the amount/cfu was less on agar than in broth cultures. Expression of the K88 adhesin during unshaken batch culture was related to the growth rate and was maximal during late logarithmic to early stationary phase. A combination of heat extraction, ammonium sulphate and isoelectric precipitation was found suitable for both large and small scale preparation of purified K88ab adhesin. Extraction of the K88 adhesin was sensitive to pH and it was postulated that this may affect the site of colonisation of by ETEC in vivo. Results of haemagglutination experiments were consistent with the hypothesis that the K88 receptor present on erythrocytes is composed of two elements, one responsible for the binding of K88ab and K88ac and a second responsible for the binding of the K88ad adhesin. Comparison of the haemagglutinating properties of cell-free and cell-bound K88 adhesin revealed some differences probably indicating a minor conformational change in the K88 adhesin on its isolation. The K88ab adhesin was found to bind to erythrocytes over a wide pH range (PH 4-9) and was inhibited by αK88ab and αK88b antisera. Inhibition of haemagglutination was noted with crude heparin, mannan and porcine gastric mucin, chondrosine and several hexosamines, glucosamine in particular. The most potent inhibitor of haemagglutination was n-dodecyl-β-D-glucopyranoside, one of a series of glucosides found to have inhibitory properties. Correlation between hydrophobicity of glucosides tested and degree of inhibition observed suggested hydrophobic forces were important in the interaction of the K88 adhesin with its receptor. The results of Scatchard and Hill plots indicated that binding of the K88ab adhesin to porcine enterocytes in the majority of cases is a two-step, three component system. The first K88 receptor (or site) had a K2. of 1.59x1014M-1 and a minimum of 4.3x104 sites/enterocyte. The second receptor (or site) had a K2 of 4.2x1012M-1 with a calculated 1.75x105 sites/enterocyte. Attempts to inhibit binding of cell-free K88 adhesin to porcine enterocytes by lectins were unsuccessful. However, several carbohydrates including trehalose, lactulose, galactose 1→4 mannopyranoside, chondrosine, galactosamine, stachyose and mannan were inhibitory. The most potent inhibitor was found to be porcine gastric mucin. Inhibition observed with n-octyl-α-D-glucopyranose was difficult to interpret in isolation because of interference with the assay, however, it agreed with the results of haemagglutination inhibition experiments.

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With the proliferation of social media sites, social streams have proven to contain the most up-to-date information on current events. Therefore, it is crucial to extract events from the social streams such as tweets. However, it is not straightforward to adapt the existing event extraction systems since texts in social media are fragmented and noisy. In this paper we propose a simple and yet effective Bayesian model, called Latent Event Model (LEM), to extract structured representation of events from social media. LEM is fully unsupervised and does not require annotated data for training. We evaluate LEM on a Twitter corpus. Experimental results show that the proposed model achieves 83% in F-measure, and outperforms the state-of-the-art baseline by over 7%.© 2014 Association for Computational Linguistics.

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Deep well injection into non-potable saline aquifers of treated domestic wastewater has been used in Florida for decades as a safe and effective alternative to ocean outfall disposal. The objectives of this study were to determine the fate and transport of injected wastewater at two deep well injection sites in Miami Dade County, Florida, USA. Detection of ammonium in the Middle Confining units of the Floridan aquifer above the injection zone at both sites has been interpreted as evidence of upward migration of injected wastewater, posing a risk to underground sources of drinking water. Historical water quality data, including ammonia, chloride, temperature, and pH from existing monitoring wells at both sites from 1983 to 2008, major ions collected monthly from 2006 and 2008, and a synoptic sampling event for stable isotopes, tritium, and dissolved gases in 2008, were used to determine the source of ammonium in groundwater and possible migration pathways. Geochemical modeling was used to determine possible effects of injected wastewater on native water and aquifer matrix geochemistry. Injected wastewater was determined to be the source of elevated ammonium concentrations above ambient water levels, based on the results of major ion concentrations, tritium, dissolved noble gases and 15N isotopes analyses. Various possible fluid migration pathways were identified at the sites. Data for the south site suggest buoyancy-driven vertical pathways to overlying aquifers bypassing the confining units, with little mixing of injected wastewater with native water as it migrated upward. Once it is introduced into an aquifer, the injectate appeared to migrate advectively with the regional groundwater flow. Geochemical modeling indicated that CO 2-enriched injected wastewater allowed for carbonate dissolution along the vertical pathways, enhancing permeability along these flowpaths. At the north site, diffusive upward flow through the confining units or offsite vertical pathways were determined to be possible, however no evidence was detected for any on-site confining unit bypass pathway. No evidence was observed at either site of injected wastewater migration to the Upper Floridan aquifer, which is used as a municipal water supply and for aquifer storage and recovery.

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Two deep-well injection sites in south Florida, USA, inject an average of 430 million liters per day (MLD) of treated domestic fresh wastewater into a deep saline aquifer 900 m below land surface. Elevated levels of NH3 (highest concentration 939 µmol) in the overlying aquifer above ambient concentrations (concentration less than 30 µmol) were evidence of the upward migration of injected fluids. Three pathways were distinguished based on ammonium, chloride and bromide ratios, and temperature. At the South District Wastewater Treatment Plant, the tracer ratios showed that the injectate remained chemically distinct as it migrated upwards through rapid vertical pathways via density-driven buoyancy. The warmer injectate (mean 28°C) retained the temperature signal as it vertically migrated upwards; however, the temperature signal did not persist as the injectate moved horizontally into the overlying aquifers. Once introduced, the injectate moved slowly horizontally through the aquifer and mixed with ambient water. At the North District Wastewater Treatment Plant, data provide strong evidence of a one-time pulse of injectate into the overlying aquifers due to improper well construction. No evidence of rapid vertical pathways was observed at the North District Wastewater Treatment Plant.

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The Kara Sea is an area uniquely suitable for studying processes in the river-sea system. This is a shallow sea, into which two great Siberian rivers, Yenisei and Ob, flow. From 1995 to 2003, the sea was studied by six international expeditions onboard the R/V Akademik Boris Petrov. This publication summarizes the results obtained, within the framework of this project, at the Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences. Various hydrogeochemical parameters, concentrations and isotopic composition of organic and carbonate carbon of the sediments, plankton, particulate organic matter, hydrocarbons, and dissolved CO2 were examined throughout the whole sea area at more than 200 sites. The d13C varies from -22 and -24 per mil where Atlantic waters enter the Kara Sea and in the north-eastern part of the water area to -27 per mil in the Yenisei and Ob estuaries. The value of d13C of the plankton is only weakly correlated with the d13C of the organic matter from the sediments and is lower by as much as 3-4 per mil. The paper presents the results obtained from a number of meridional river-sea profiles. It was determined from the relations between the isotopic compositions of plankton and particulate matter that the river waters carry material consisting of 70% detrital-humus matter and 30% planktonogenic material in the river part, and the material contained in the offshore waters consists of 30% terrigenous components, with the contribution of bioproducers amounting to 70%. The carbon isotopic composition of the plankton ranges from -29 to -35 per mil in the riverine part, from -28 to -27 per mil in the estuaries, and from -27.0 to -25 per mil in the marine part. The relative lightness of the carbon isotopic composition of plankton in Arctic waters is explained by the temperature effect, elevated CO2 concentrations, and long-distance CO2 supply to the sea with river waters. The data obtained on the isotopic composition of CO2 in the surface waters of the Kara Sea were used to map the distribution of d13C. The complex of hydrocarbon gases extracted from the waters included methane, C2-C5, and unsaturated C2=-C4= hydrocarbons, for which variations in the concentrations in the waters were studied along river-estuary-sea profiles. The geochemistry of hydrocarbon gases in surface fresh waters is characterized by comparable concentrations of methane (0.3-5 µl/l) and heavier hydrocarbons, including unsaturated ones. Microbiological methane with d13C from -105 to -90 per mil first occurs in the sediments at depths of 40-200 cm. The sediments practically everywhere display traces of methane oxidation in the form of a shift of the d13C of methane toward higher values and the occurrence of autogenic carbonate material, including ikaite, enriched in the light isotope. Ikaite (d13C from -25 to -60 per mil) was found and examined in several profiles. The redox conditions in the sediments varied from normal in the southern part of the sea to highly oxidized along the Novaya Zemlya Trough. Vertical sections through the sediments of the latter exemplify the complete suppression of the biochemical activity of microorganisms. Our data provide insight into the biogeochemistry of the Kara Sea and make it possible to specify the background values needed for ecological control during the future exploration operations and extraction of hydrocarbons in the Kara Sea.

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Leg 165 of the Ocean Drilling Program afforded a unique opportunity to investigate organic and inorganic geochemistry across a wide gradient of sediment compositions and corresponding chemical pathways. The solid fractions at Sites 998, 999, 1000, and 1001 reveal varying proportions of reactive carbonate species, a labile volcanic ash fraction occurring in discrete layers and as a dispersed component, and detrital fluxes that derive from continental weathering. The relative proportions and reactivities of these end-members strongly dictate the character of the diagenetic profiles observed during the pore-water work of Leg 165. In addition, alteration of the well-characterized basaltic basement at Site 1001 has provided a strong signal that is reflected in many of the dissolved components. The relative effects of basement alteration and diagenesis within the sediment column are discussed in terms of downcore relationships for dissolved calcium and magnesium. With the exception of Site 1002 in the Cariaco Basin, the sediments encountered during Leg 165 were uniformly deficient in organic carbon (typically <0.1 wt%). Consequently, rates of organic oxidation were generally low and dominated by suboxic pathways with subordinate levels of bacterial sulfate reduction and methanogenesis. The low rates of organic remineralization are supported by modeled rates of sulfate reduction. Site 1000 provided an exception to the generally low levels of microbially mediated redox cycling. At this site the sediment is slightly more enriched in organic phases, and externally derived thermogenic hydrocarbons appear to aid in driving enhanced levels of redox diagenesis at great depths below the seafloor. The entrapment of these volatiles corresponds with a permeability seal defined by a pronounced Miocene minimum in calcium carbonate concentration recognized throughout the basin and with a dramatic downcore increase in the magnitude of limestone lithification. The latter has been tentatively linked to increases in alkalinity associated with microbial oxidation of organic matter and gaseous hydrocarbons. Recognition and quantification of previously unconstrained large volumes and frequencies of Eocene and Miocene silicic volcanic ash within the Caribbean Basin is one of the major findings of Leg 165. High frequencies of volcanic ash layers manifest as varied but often dominant controls on pore-water chemistry. Sulfur isotope results are presented that speak to secondary metal and sulfur enrichments observed in ash layers sampled during Leg 165. Ultimately, a better mechanistic understanding of these processes and the extent to which they have varied spatially and temporally may bear on the global mass balances for a range of major and minor dissolved components of seawater.

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Free and ester-bound lipid biomarkers were analysed in oxidised and unoxidised parts of four distinct turbidites from the Madeira Abyssal Plain (MAP), which contained 1 to 2% organic carbon homogeneously distributed throughout the turbidites at the time they were deposited. These turbidites are well suited to study the effects of oxic degradation on lipid biomarkers without the complicating influence of varying organic matter sources, sedimentation rates, or bioturbation. One sample from the oxidised turbidite was compared with two samples from the unoxidised part of each turbidite. Postdepositional oxic degradation decreased concentrations of biomarkers by several orders of magnitude. The ester-bound lipids were degraded to a far lesser extent than their free counterparts were. The extent of degradation of different compounds differed substantially. Within a specific class of biomarkers, degradation also took place to a different extent, altering their distributions. This study shows that oxic degradation of the organic matter may have a profound effect on the biomarker fingerprint and may result in a severe bias in, for example, the interpretation of organic matter sources and the estimation of the palaeoproductivity of specific groups of phytoplankton.

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Is phraseology the third articulation of language? Fresh insights into a theoretical conundrum Jean-Pierre Colson University of Louvain (Louvain-la-Neuve, Belgium) Although the notion of phraseology is now used across a wide range of linguistic disciplines, its definition and the classification of phraseological units remain a subject of intense debate. It is generally agreed that phraseology implies polylexicality, but this term is problematic as well, because it brings us back to one of the most controversial topics in modern linguistics: the definition of a word. On the other hand, another widely accepted principle of language is the double articulation or duality of patterning (Martinet 1960): the first articulation consists of morphemes and the second of phonemes. The very definition of morphemes, however, also poses several problems, and the situation becomes even more confused if we wish to take phraseology into account. In this contribution, I will take the view that a corpus-based and computational approach to phraseology may shed some new light on this theoretical conundrum. A better understanding of the basic units of meaning is necessary for more efficient language learning and translation, especially in the case of machine translation. Previous research (Colson 2011, 2012, 2013, 2014), Corpas Pastor (2000, 2007, 2008, 2013, 2015), Corpas Pastor & Leiva Rojo (2011), Leiva Rojo (2013), has shown the paramount importance of phraseology for translation. A tentative step towards a coherent explanation of the role of phraseology in language has been proposed by Mejri (2006): it is postulated that a third articulation of language intervenes at the level of words, including simple morphemes, sequences of free and bound morphemes, but also phraseological units. I will present results from experiments with statistical associations of morphemes across several languages, and point out that (mainly) isolating languages such as Chinese are interesting for a better understanding of the interplay between morphemes and phraseological units. Named entities, in particular, are an extreme example of intertwining cultural, statistical and linguistic elements. Other examples show that the many borrowings and influences that characterize European languages tend to give a somewhat blurred vision of the interplay between morphology and phraseology. From a statistical point of view, the cpr-score (Colson 2016) provides a methodology for adapting the automatic extraction of phraseological units to the morphological structure of each language. The results obtained can therefore be used for testing hypotheses about the interaction between morphology, phraseology and culture. Experiments with the cpr-score on the extraction of Chinese phraseological units show that results depend on how the basic units of meaning are defined: a morpheme-based approach yields good results, which corroborates the claim by Beck and Mel'čuk (2011) that the association of morphemes into words may be similar to the association of words into phraseological units. A cross-linguistic experiment carried out for English, French, Spanish and Chinese also reveals that the results are quite compatible with Mejri’s hypothesis (2006) of a third articulation of language. Such findings, if confirmed, also corroborate the notion of statistical semantics in language. To illustrate this point, I will present the PhraseoRobot (Colson 2016), a computational tool for extracting phraseological associations around key words from the media, such as Brexit. The results confirm a previous study on the term globalization (Colson 2016): a significant part of sociolinguistic associations prevailing in the media is related to phraseology in the broad sense, and can therefore be partly extracted by means of statistical scores. References Beck, D. & I. Mel'čuk (2011). Morphological phrasemes and Totonacan verbal morphology. Linguistics 49/1: 175-228. Colson, J.-P. (2011). La traduction spécialisée basée sur les corpus : une expérience dans le domaine informatique. In : Sfar, I. & S. Mejri, La traduction de textes spécialisés : retour sur des lieux communs. Synergies Tunisie n° 2. Gerflint, Agence universitaire de la Francophonie, p. 115-123. Colson, J.-P. (2012). Traduire le figement en langue de spécialité : une expérience de phraséologie informatique. In : Mogorrón Huerta, P. & S. Mejri (dirs.), Lenguas de especialidad, traducción, fijación / Langues spécialisées, figement et traduction. Encuentros Mediterráneos / Rencontres Méditerranéennes, N°4. Universidad de Alicante, p. 159-171. Colson, J.-P. (2013). Pratique traduisante et idiomaticité : l’importance des structures semi-figées. In : Mogorrón Huerta, P., Gallego Hernández, D., Masseau, P. & Tolosa Igualada, M. (eds.), Fraseología, Opacidad y Traduccíon. Studien zur romanischen Sprachwissenschaft und interkulturellen Kommunikation (Herausgegeben von Gerd Wotjak). Frankfurt am Main, Peter Lang, p. 207-218. Colson, J.-P. (2014). La phraséologie et les corpus dans les recherches traductologiques. Communication lors du colloque international Europhras 2014, Association Européenne de Phraséologie. Université de Paris Sorbonne, 10-12 septembre 2014. Colson, J-P. (2016). Set phrases around globalization : an experiment in corpus-based computational phraseology. In: F. Alonso Almeida, I. Ortega Barrera, E. Quintana Toledo and M. Sánchez Cuervo (eds.), Input a Word, Analyse the World: Selected Approaches to Corpus Linguistics. Newcastle upon Tyne: Cambridge Scholars Publishing, p. 141-152. Corpas Pastor, G. (2000). Acerca de la (in)traducibilidad de la fraseología. In: G. Corpas Pastor (ed.), Las lenguas de Europa: Estudios de fraseología, fraseografía y traducción. Granada: Comares, p. 483-522. Corpas Pastor, G. (2007). Europäismen - von Natur aus phraseologische Äquivalente? Von blauem Blut und sangre azul. In: M. Emsel y J. Cuartero Otal (eds.), Brücken: Übersetzen und interkulturelle Kommunikationen. Festschrift für Gerd Wotjak zum 65. Geburtstag, Fráncfort: Peter Lang, p. 65-77. Corpas Pastor, G. (2008). Investigar con corpus en traducción: los retos de un nuevo paradigma [Studien zur romanische Sprachwissenschaft und interkulturellen Kommunikation, 49], Fráncfort: Peter Lang. Corpas Pastor, G. (2013). Detección, descripción y contraste de las unidades fraseológicas mediante tecnologías lingüísticas. In Olza, I. & R. Elvira Manero (eds.) Fraseopragmática. Berlin: Frank & Timme, p. 335-373. Leiva Rojo, J. (2013). La traducción de unidades fraseológicas (alemán-español/español-alemán) como parámetro para la evaluación y revisión de traducciones. In: Mellado Blanco, C., Buján, P, Iglesias N.M., Losada M.C. & A. Mansilla (eds), La fraseología del alemán y el español: lexicografía y traducción. ELS, Etudes Linguistiques / Linguistische Studien, Band 11. München: Peniope, p. 31-42. Leiva Rojo, J. & G. Corpas Pastor (2011). Placing Italian idioms in a foreign milieu: a case study. In: Pamies Bertrán, A., Luque Nadal, L., Bretana, J. &; M. Pazos (eds), (2011). Multilingual phraseography. Second Language Learning and Translation Applications. Baltmannsweiler: Schneider Verlag (Colección: Phraseologie und Parömiologie, 28), p. 289-298. Martinet, A. (1966). Eléments de linguistique générale. Paris: Colin. Mejri, S. (2006). Polylexicalité, monolexicalité et double articulation. Cahiers de Lexicologie 2: 209-221.

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Salinity gradient power (SGP) is the energy that can be obtained from the mixing entropy of two solutions with a different salt concentration. River estuary, as a place for mixing salt water and fresh water, has a huge potential of this renewable energy. In this study, this potential in the estuaries of rivers leading to the Persian Gulf and the factors affecting it are analysis and assessment. Since most of the full water rivers are in the Asia, this continent with the potential power of 338GW is a second major source of energy from the salinity gradient power in the world (Wetsus institute, 2009). Persian Gulf, with the proper salinity gradient in its river estuaries, has Particular importance for extraction of this energy. Considering the total river flow into the Persian Gulf, which is approximately equal to 3486 m3/s, the amount of theoretical extractable power from salinity gradient in this region is 5.2GW. Iran, with its numerous rivers along the coast of the Persian Gulf, has a great share of this energy source. For example, with study calculations done on data from three hydrometery stations located on the Arvand River, Khorramshahr Station with releasing 1.91M/ energy which is obtained by combining 1.26m3 river water with 0.74 m3 sea water, is devoted to itself extracting the maximum amount of extractable energy. Considering the average of annual discharge of Arvand River in Khorramshahr hydrometery station, the amount of theoretical extractable power is 955 MW. Another part of parameters that are studied in this research, are the intrusion length of salt water and its flushing time in the estuary that have a significant influence on the salinity gradient power. According to the calculation done in conditions HWS and the average discharge of rivers, the maximum of salinity intrusion length in to the estuary of the river by 41km is related to Arvand River and the lowest with 8km is for Helle River. Also the highest rate of salt water flushing time in the estuary with 9.8 days is related to the Arvand River and the lowest with 3.3 days is for Helle River. Influence of these two parameters on reduces the amount of extractable energy from salinity gradient power as well as can be seen in the estuaries of the rivers studied. For example, at the estuary of the Arvand River in the interval 8.9 days, salinity gradient power decreases 9.2%. But another part of this research focuses on the design of a suitable system for extracting electrical energy from the salinity gradient. So far, five methods have been proposed to convert this energy to electricity that among them, reverse electro-dialysis (RED) method and pressure-retarded osmosis (PRO) method have special importance in practical terms. In theory both techniques generate the same amount of energy from given volumes of sea and river water with specified salinity; in practice the RED technique seems to be more attractive for power generation using sea water and river water. Because it is less necessity of salinity gradient to PRO method. In addition to this, in RED method, it does not need to use turbine to change energy and the electricity generation is started when two solutions are mixed. In this research, the power density and the efficiency of generated energy was assessment by designing a physical method. The physical designed model is an unicellular reverse electro-dialysis battery with nano heterogenic membrane has 20cmx20cm dimension, which produced power density 0.58 W/m2 by using river water (1 g NaCl/lit) and sea water (30 g NaCl/lit) in laboratorial condition. This value was obtained because of nano method used on the membrane of this system and suitable design of the cell which led to increase the yield of the system efficiency 11% more than non nano ones.