WorldWideScience

Sample records for surface seawater dms

  1. Vertical variability of seawater DMS in the South Pacific Ocean and its implication for atmospheric and surface seawater DMS.

    Science.gov (United States)

    Lee, Gangwoong; Park, Jooyoung; Jang, Yuwoon; Lee, Meehye; Kim, Kyung-Ryul; Oh, Jae-Ryoung; Kim, Dongseon; Yi, Hi-Il; Kim, Tong-Yup

    2010-02-01

    Shipboard measurements of atmospheric dimethylsulfide (DMS) and sea surface water DMS were performed aboard the R/V Onnuri across the South Pacific from Santiago, Chile to Fiji in February 2000. Hydrographic profiles of DMS, dissolved dimethylsulfoniopropionate (DMSP(d)), and particulate DMSP(p) in the upper 200m were obtained at 16 stations along the track. Atmospheric and sea surface water DMS concentrations ranged from 3 to 442pptv and from 0.1 to 19.9nM, respectively; the mean values of 61pptv and 2.1nM, respectively, were comparable to those from previous studies in the South Pacific. The South Pacific Gyre was distinguished by longitudinal-vertical distributions of DMS, DMSP(d), and DMSP(p), which was thought to be associated with the characteristic modification of biological activities that occurs mainly due to significant change in water temperature. The averaged DMS maximum appeared at 40m depth, whereas DMSP(p) and DMSP(d) maxima coincided with that of dissolved oxygen content at 60-80m. The sea-to-air fluxes of DMS were estimated to be 0.4-11.3micromold(-1)m(-2) (mean=2.8micromold(-1)m(-2)). A fairly good correlation between atmospheric DMS and sea-to-air DMS flux indicated that atmospheric DMS concentration was more sensitive to change in physical parameters than its photochemical removal process or surface seawater DMS concentrations.

  2. Global oceanic DMS data inter-comparability

    NARCIS (Netherlands)

    Bell, T. G.; Malin, G.; Lee, G. A.; Stefels, J.; Archer, S.; Steinke, M.; Matrai, P.

    The global surface seawater dimethylsulphide (DMS) database (http://saga.pmel.noaa.gov/dms/) contains > 50,000 data points and is the second largest trace gas database after carbon dioxide. However, there has been relatively little quality control on the data that have been collated to date.

  3. Sulfur isotope homogeneity of oceanic DMSP and DMS.

    Science.gov (United States)

    Amrani, Alon; Said-Ahmad, Ward; Shaked, Yeala; Kiene, Ronald P

    2013-11-12

    Oceanic emissions of volatile dimethyl sulfide (DMS) represent the largest natural source of biogenic sulfur to the global atmosphere, where it mediates aerosol dynamics. To constrain the contribution of oceanic DMS to aerosols we established the sulfur isotope ratios ((34)S/(32)S ratio, δ(34)S) of DMS and its precursor, dimethylsulfoniopropionate (DMSP), in a range of marine environments. In view of the low oceanic concentrations of DMS/P, we applied a unique method for the analysis of δ(34)S at the picomole level in individual compounds. Surface water DMSP collected from six different ocean provinces revealed a remarkable consistency in δ(34)S values ranging between +18.9 and +20.3‰. Sulfur isotope composition of DMS analyzed in freshly collected seawater was similar to δ(34)S of DMSP, showing that the in situ fractionation between these species is small (DMS to the atmosphere results in a relatively small fractionation (-0.5 ± 0.2‰) compared with the seawater DMS pool. Because δ(34)S values of oceanic DMS closely reflect that of DMSP, we conclude that the homogenous δ(34)S of DMSP at the ocean surface represents the δ(34)S of DMS emitted to the atmosphere, within +1‰. The δ(34)S of oceanic DMS flux to the atmosphere is thus relatively constant and distinct from anthropogenic sources of atmospheric sulfate, thereby enabling estimation of the DMS contribution to aerosols.

  4. Photodegradation of dimethyl sulfide (DMS) in natural waters: laboratory assessment of the nitrate-photolysis-induced DMS oxidation.

    Science.gov (United States)

    Bouillon, René-Christian; Miller, William L

    2005-12-15

    The interaction of sunlight and dissolved chromophoric matter produces reactive chemical species that are significant in the removal of dimethyl sulfide (DMS) in the surface ocean. Using artificial solar radiation, we examined the role of several inorganic components of seawater on the kinetics of NO3- -photolysis-induced DMS removal in aqueous solution. This study strongly suggests that NO3- photolysis products react significantly with DMS in aqueous solution possibly via an electrophilic attack on the electron-rich sulfur atom. This supports previous field observations that indicate that NO3- photolysis has a substantial control on DMS photochemistry in nutrient-rich waters. A key finding of this research is that the oxidation rate of DMS induced by NO3- photolysis is dramatically enhanced in the presence of bromide ion. Moreover, our results suggest that bicarbonate/carbonate ions are involved in free radical production/scavenging processes important for DMS photochemistry. These reactions are pH dependent. We propose that DMS removal by some selective free radicals derived from bromide and bicarbonate/carbonate ion oxidation is a potentially important and previously unrecognized pathway for DMS photodegradation in marine waters.

  5. The use of algorithms to predict surface seawater dimethyl sulphide concentrations in the SE Pacific, a region of steep gradients in primary productivity, biomass and mixed layer depth

    Directory of Open Access Journals (Sweden)

    A. J. Hind

    2011-01-01

    Full Text Available Dimethyl sulphide (DMS is an important precursor of cloud condensation nuclei (CCN, particularly in the remote marine atmosphere. The SE Pacific is consistently covered with a persistent stratocumulus layer that increases the albedo over this large area. It is not certain whether the source of CCN to these clouds is natural and oceanic or anthropogenic and terrestrial. This unknown currently limits our ability to reliably model either the cloud behaviour or the oceanic heat budget of the region. In order to better constrain the marine source of CCN, it is necessary to have an improved understanding of the sea-air flux of DMS. Of the factors that govern the magnitude of this flux, the greatest unknown is the surface seawater DMS concentration. In the study area, there is a paucity of such data, although previous measurements suggest that the concentration can be substantially variable. In order to overcome such data scarcity, a number of climatologies and algorithms have been devised in the last decade to predict seawater DMS. Here we test some of these in the SE Pacific by comparing predictions with measurements of surface seawater made during the Vamos Ocean-Cloud-Atmosphere-Land Study Regional Experiment (VOCALS-REx in October and November of 2008. We conclude that none of the existing algorithms reproduce local variability in seawater DMS in this region very well. From these findings, we recommend the best algorithm choice for the SE Pacific and suggest lines of investigation for future work.

  6. MODFLOW-2000, the U.S. Geological Survey Modular Ground-Water Model--Documentation of the SEAWAT-2000 Version with the Variable-Density Flow Process (VDF) and the Integrated MT3DMS Transport Process (IMT)

    Science.gov (United States)

    Langevin, Christian D.; Shoemaker, W. Barclay; Guo, Weixing

    2003-01-01

    SEAWAT-2000 is the latest release of the SEAWAT computer program for simulation of three-dimensional, variable-density, transient ground-water flow in porous media. SEAWAT-2000 was designed by combining a modified version of MODFLOW-2000 and MT3DMS into a single computer program. The code was developed using the MODFLOW-2000 concept of a process, which is defined as ?part of the code that solves a fundamental equation by a specified numerical method.? SEAWAT-2000 contains all of the processes distributed with MODFLOW-2000 and also includes the Variable-Density Flow Process (as an alternative to the constant-density Ground-Water Flow Process) and the Integrated MT3DMS Transport Process. Processes may be active or inactive, depending on simulation objectives; however, not all processes are compatible. For example, the Sensitivity and Parameter Estimation Processes are not compatible with the Variable-Density Flow and Integrated MT3DMS Transport Processes. The SEAWAT-2000 computer code was tested with the common variable-density benchmark problems and also with problems representing evaporation from a salt lake and rotation of immiscible fluids.

  7. Sensitivity of modelled sulfate aerosol and its radiative effect on climate to ocean DMS concentration and air–sea flux

    Directory of Open Access Journals (Sweden)

    J.-E. Tesdal

    2016-09-01

    Full Text Available Dimethylsulfide (DMS is a well-known marine trace gas that is emitted from the ocean and subsequently oxidizes to sulfate in the atmosphere. Sulfate aerosols in the atmosphere have direct and indirect effects on the amount of solar radiation reaching the Earth's surface. Thus, as a potential source of sulfate, ocean efflux of DMS needs to be accounted for in climate studies. Seawater concentration of DMS is highly variable in space and time, which in turn leads to high spatial and temporal variability in ocean DMS emissions. Because of sparse sampling (in both space and time, large uncertainties remain regarding ocean DMS concentration. In this study, we use an atmospheric general circulation model with explicit aerosol chemistry (CanAM4.1 and several climatologies of surface ocean DMS concentration to assess uncertainties about the climate impact of ocean DMS efflux. Despite substantial variation in the spatial pattern and seasonal evolution of simulated DMS fluxes, the global-mean radiative effect of sulfate is approximately linearly proportional to the global-mean surface flux of DMS; the spatial and temporal distribution of ocean DMS efflux has only a minor effect on the global radiation budget. The effect of the spatial structure, however, generates statistically significant changes in the global-mean concentrations of some aerosol species. The effect of seasonality on the net radiative effect is larger than that of spatial distribution and is significant at global scale.

  8. The distribution of methylated sulfur compounds, DMS and DMSP, in Canadian subarctic and Arctic marine waters during summer 2015

    Directory of Open Access Journals (Sweden)

    T. Jarníková

    2018-04-01

    Full Text Available We present seawater concentrations of dimethyl sulfide (DMS and dimethylsulfoniopropionate (DMSP measured across a transect from the Labrador Sea to the Canadian Arctic Archipelago during summer 2015. Using an automated ship-board gas chromatography system and a membrane-inlet mass spectrometer, we measured a wide range of DMS (∼ 1 to 18 nM and DMSP (∼ 1 to 150 nM concentrations. The highest DMS and DMSP concentrations occurred in a localized region of Baffin Bay, where surface waters were characterized by high chlorophyll a (chl a fluorescence, indicative of elevated phytoplankton biomass. Across the full sampling transect, there were only weak relationships between DMS(P, chl a fluorescence and other measured variables, including positive relationships between DMSP : chl a ratios and several taxonomic marker pigments, and elevated DMS(P concentrations in partially ice-covered areas. Our high spatial resolution measurements allowed us to examine DMS variability over small scales (< 1 km, documenting strong DMS concentration gradients across surface hydrographic frontal features. Our new observations fill in an important observational gap in the Arctic Ocean and provide additional information on sea–air DMS fluxes from this ocean region. In addition, this study constitutes a significant contribution to the existing Arctic DMS(P dataset and provides a baseline for future measurements in the region.

  9. Gradient flux measurements of sea–air DMS transfer during the Surface Ocean Aerosol Production (SOAP experiment

    Directory of Open Access Journals (Sweden)

    M. J. Smith

    2018-04-01

    Full Text Available Direct measurements of marine dimethylsulfide (DMS fluxes are sparse, particularly in the Southern Ocean. The Surface Ocean Aerosol Production (SOAP voyage in February–March 2012 examined the distribution and flux of DMS in a biologically active frontal system in the southwest Pacific Ocean. Three distinct phytoplankton blooms were studied with oceanic DMS concentrations as high as 25 nmol L−1. Measurements of DMS fluxes were made using two independent methods: the eddy covariance (EC technique using atmospheric pressure chemical ionization–mass spectrometry (API-CIMS and the gradient flux (GF technique from an autonomous catamaran platform. Catamaran flux measurements are relatively unaffected by airflow distortion and are made close to the water surface, where gas gradients are largest. Flux measurements were complemented by near-surface hydrographic measurements to elucidate physical factors influencing DMS emission. Individual DMS fluxes derived by EC showed significant scatter and, at times, consistent departures from the Coupled Ocean–Atmosphere Response Experiment gas transfer algorithm (COAREG. A direct comparison between the two flux methods was carried out to separate instrumental effects from environmental effects and showed good agreement with a regression slope of 0.96 (r2 = 0.89. A period of abnormal downward atmospheric heat flux enhanced near-surface ocean stratification and reduced turbulent exchange, during which GF and EC transfer velocities showed good agreement but modelled COAREG values were significantly higher. The transfer velocity derived from near-surface ocean turbulence measurements on a spar buoy compared well with the COAREG model in general but showed less variation. This first direct comparison between EC and GF fluxes of DMS provides confidence in compilation of flux estimates from both techniques, as well as in the stable periods when the observations are not well predicted by the COAREG

  10. Gradient flux measurements of sea-air DMS transfer during the Surface Ocean Aerosol Production (SOAP) experiment

    Science.gov (United States)

    Smith, Murray J.; Walker, Carolyn F.; Bell, Thomas G.; Harvey, Mike J.; Saltzman, Eric S.; Law, Cliff S.

    2018-04-01

    Direct measurements of marine dimethylsulfide (DMS) fluxes are sparse, particularly in the Southern Ocean. The Surface Ocean Aerosol Production (SOAP) voyage in February-March 2012 examined the distribution and flux of DMS in a biologically active frontal system in the southwest Pacific Ocean. Three distinct phytoplankton blooms were studied with oceanic DMS concentrations as high as 25 nmol L-1. Measurements of DMS fluxes were made using two independent methods: the eddy covariance (EC) technique using atmospheric pressure chemical ionization-mass spectrometry (API-CIMS) and the gradient flux (GF) technique from an autonomous catamaran platform. Catamaran flux measurements are relatively unaffected by airflow distortion and are made close to the water surface, where gas gradients are largest. Flux measurements were complemented by near-surface hydrographic measurements to elucidate physical factors influencing DMS emission. Individual DMS fluxes derived by EC showed significant scatter and, at times, consistent departures from the Coupled Ocean-Atmosphere Response Experiment gas transfer algorithm (COAREG). A direct comparison between the two flux methods was carried out to separate instrumental effects from environmental effects and showed good agreement with a regression slope of 0.96 (r2 = 0.89). A period of abnormal downward atmospheric heat flux enhanced near-surface ocean stratification and reduced turbulent exchange, during which GF and EC transfer velocities showed good agreement but modelled COAREG values were significantly higher. The transfer velocity derived from near-surface ocean turbulence measurements on a spar buoy compared well with the COAREG model in general but showed less variation. This first direct comparison between EC and GF fluxes of DMS provides confidence in compilation of flux estimates from both techniques, as well as in the stable periods when the observations are not well predicted by the COAREG model.

  11. DMS role in ENSO cycle in the tropics: DMS Role in ENSO Cycle in Tropics

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Li [Scripps Institution of Oceanography, University of California, San Diego, La Jolla California USA; Now at Department of Earth System Science, University of California, Irvine California USA; Cameron-Smith, Philip [Atmospheric, Earth and Energy Division, Lawrence Livermore National Laboratory, Livermore California USA; Russell, Lynn M. [Scripps Institution of Oceanography, University of California, San Diego, La Jolla California USA; Ghan, Steven J. [Atmospheric Science and Global Change Division, Pacific Northwest National Laboratory, Richland Washington USA; Liu, Ying [Atmospheric Science and Global Change Division, Pacific Northwest National Laboratory, Richland Washington USA; Elliott, Scott [Climate Ocean Sea Ice Modeling, Los Alamos National Laboratory, Los Alamos New Mexico USA; Yang, Yang [Scripps Institution of Oceanography, University of California, San Diego, La Jolla California USA; Atmospheric Science and Global Change Division, Pacific Northwest National Laboratory, Richland Washington USA; Lou, Sijia [Scripps Institution of Oceanography, University of California, San Diego, La Jolla California USA; Atmospheric Science and Global Change Division, Pacific Northwest National Laboratory, Richland Washington USA; Lamjiri, Maryam A. [Scripps Institution of Oceanography, University of California, San Diego, La Jolla California USA; Manizza, Manfredi [Scripps Institution of Oceanography, University of California, San Diego, La Jolla California USA

    2016-11-16

    We examined the multiyear mean and variability of dimethyl sulfide (DMS) and its relationship to sulfate aerosols, as well as cloud microphysical and radiative properties. We conducted a 150 year simulation using preindustrial conditions produced by the Community Earth System Model embedded with a dynamic DMS module. The model simulated the mean spatial distribution of DMS emissions and burden, as well as sulfur budgets associated with DMS, SO2, H2SO4, and sulfate that were generally similar to available observations and inventories for a variety of regions. Changes in simulated sea-to-air DMS emissions and associated atmospheric abundance, along with associated aerosols and cloud and radiative properties, were consistently dominated by El Niño–Southern Oscillation (ENSO) cycle in the tropical Pacific region. Simulated DMS, aerosols, and clouds showed a weak positive feedback on sea surface temperature. This feedback suggests a link among DMS, aerosols, clouds, and climate on interannual timescales. The variability of DMS emissions associated with ENSO was primarily caused by a higher variation in wind speed during La Niña events. The simulation results also suggest that variations in DMS emissions increase the frequency of La Niña events but do not alter ENSO variability in terms of the standard deviation of the Niño 3 sea surface temperature anomalies.

  12. Environmental constraints on the production and removal of the climatically active gas dimethylsulphide (DMS) and implications for ecosystem modelling

    NARCIS (Netherlands)

    Stefels, Jacqueline; Steinke, Michael; Turner, Suzanne; Malin, Gill; Belviso, Sauveur

    Seawater concentrations of the climate-cooling, volatile sulphur compound dimethylsulphide (DMS) are the result of numerous production and consumption processes within the marine ecosystem. Due to this complex nature, it is difficult to predict temporal and geographical distribution patterns of DMS

  13. Air/sea DMS gas transfer in the North Atlantic: evidence for limited interfacial gas exchange at high wind speed

    Science.gov (United States)

    Bell, T. G.; De Bruyn, W.; Miller, S. D.; Ward, B.; Christensen, K.; Saltzman, E. S.

    2013-05-01

    Shipboard measurements of eddy covariance DMS air/sea fluxes and seawater concentration were carried out in the North Atlantic bloom region in June/July 2011. Gas transfer coefficients (k660) show a linear dependence on mean horizontal wind speed at wind speeds up to 11 m s-1. At higher wind speeds the relationship between k660 and wind speed weakens. At high winds, measured DMS fluxes were lower than predicted based on the linear relationship between wind speed and interfacial stress extrapolated from low to intermediate wind speeds. In contrast, the transfer coefficient for sensible heat did not exhibit this effect. The apparent suppression of air/sea gas flux at higher wind speeds appears to be related to sea state, as determined from shipboard wave measurements. These observations are consistent with the idea that long waves suppress near surface water side turbulence, and decrease interfacial gas transfer. This effect may be more easily observed for DMS than for less soluble gases, such as CO2, because the air/sea exchange of DMS is controlled by interfacial rather than bubble-mediated gas transfer under high wind speed conditions.

  14. Air-sea dimethylsulfide (DMS) gas transfer in the North Atlantic: evidence for limited interfacial gas exchange at high wind speed

    Science.gov (United States)

    Bell, T. G.; De Bruyn, W.; Miller, S. D.; Ward, B.; Christensen, K.; Saltzman, E. S.

    2013-11-01

    Shipboard measurements of eddy covariance dimethylsulfide (DMS) air-sea fluxes and seawater concentration were carried out in the North Atlantic bloom region in June/July 2011. Gas transfer coefficients (k660) show a linear dependence on mean horizontal wind speed at wind speeds up to 11 m s-1. At higher wind speeds the relationship between k660 and wind speed weakens. At high winds, measured DMS fluxes were lower than predicted based on the linear relationship between wind speed and interfacial stress extrapolated from low to intermediate wind speeds. In contrast, the transfer coefficient for sensible heat did not exhibit this effect. The apparent suppression of air-sea gas flux at higher wind speeds appears to be related to sea state, as determined from shipboard wave measurements. These observations are consistent with the idea that long waves suppress near-surface water-side turbulence, and decrease interfacial gas transfer. This effect may be more easily observed for DMS than for less soluble gases, such as CO2, because the air-sea exchange of DMS is controlled by interfacial rather than bubble-mediated gas transfer under high wind speed conditions.

  15. Dynamic Bubble Surface Tension Measurements in Northwest Atlantic Seawater

    Science.gov (United States)

    Kieber, D. J.; Long, M. S.; Keene, W. C.; Kinsey, J. D.; Frossard, A. A.; Beaupre, S. R.; Duplessis, P.; Maben, J. R.; Lu, X.; Chang, R.; Zhu, Y.; Bisgrove, J.

    2017-12-01

    Numerous reports suggest that most organic matter (OM) associated with newly formed primary marine aerosol (PMA) originates from the sea-surface microlayer. However, surface-active OM rapidly adsorbs onto bubble surfaces in the water column and is ejected into the atmosphere when bubbles burst at the air-water interface. Here we present dynamic surface tension measurements of bubbles produced in near surface seawater from biologically productive and oligotrophic sites and in deep seawater collected from 2500 m in the northwest Atlantic. In all cases, the surface tension of bubble surfaces decreased within seconds after the bubbles were exposed to seawater. These observations demonstrate that bubble surfaces are rapidly saturated by surfactant material scavenged from seawater. Spatial and diel variability in bubble surface evolution indicate corresponding variability in surfactant concentrations and/or composition. Our results reveal that surface-active OM is found throughout the water column, and that at least some surfactants are not of recent biological origin. Our results also support the hypothesis that the surface microlayer is a minor to negligible source of OM associated with freshly produced PMA.

  16. Biogenesis of the demarcation membrane system (DMS) in megakaryocytes.

    Science.gov (United States)

    Eckly, Anita; Heijnen, Harry; Pertuy, Fabien; Geerts, Willie; Proamer, Fabienne; Rinckel, Jean-Yves; Léon, Catherine; Lanza, François; Gachet, Christian

    2014-02-06

    The demarcation membrane system (DMS) in megakaryocytes forms the plasma membrane (PM) of future platelets. Using confocal microscopy, electron tomography, and large volume focused ion beam/scanning electron microscopy (FIB/SEM), we determined the sequential steps of DMS formation. We identified a pre-DMS that initiated at the cell periphery and was precisely located between the nuclear lobes. At all developmental stages, the DMS remained continuous with the cell surface. The number of these connections correlated well with the nuclear lobulation, suggesting a relationship with cleavage furrow formation and abortive cytokinesis. On DMS expansion, Golgi complexes assembled around the pre-DMS, and fusion profiles between trans-golgi network-derived vesicles and the DMS were observed. Brefeldin-A reduced DMS expansion, indicating that the exocytic pathway is essential for DMS biogenesis. Close contacts between the endoplasmic reticulum (ER) and the DMS were detected, suggesting physical interaction between the 2 membrane systems. FIB/SEM revealed that the DMS forms an intertwined tubular membrane network resembling the platelet open canalicular system. We thus propose the following steps in DMS biogenesis: (1) focal membrane assembly at the cell periphery; (2) PM invagination and formation of a perinuclear pre-DMS; (3) expansion through membrane delivery from Golgi complexes; and (4) ER-mediated lipid transfer.

  17. The Hydrophobic Region of the DmsA Twin-Arginine Leader Peptide Determines Specificity with Chaperone DmsD

    OpenAIRE

    Winstone, Tara M. L.; Tran, Vy A.; Turner, Raymond J.

    2013-01-01

    The system specific chaperone DmsD plays a role in the maturation of the catalytic subunit of dimethyl sulfoxide (DMSO) reductase, DmsA. Pre-DmsA contains a 45-amino acid twin-arginine leader peptide that is important for targeting and translocation of folded and cofactor-loaded DmsA by the twin-arginine translocase. DmsD has previously been shown to interact with the complete twin-arginine leader peptide of DmsA. In this study, isothermal titration calorimetry was used to investigate the the...

  18. Strong relationship between DMS and the solar radiation dose over the global surface ocean.

    Science.gov (United States)

    Vallina, Sergio M; Simó, Rafel

    2007-01-26

    Marine biogenic dimethylsulfide (DMS) is the main natural source of tropospheric sulfur, which may play a key role in cloud formation and albedo over the remote ocean. Through a global data analysis, we found that DMS concentrations are highly positively correlated with the solar radiation dose in the upper mixed layer of the open ocean, irrespective of latitude, plankton biomass, or temperature. This is a necessary condition for the feasibility of a negative feedback in which light-attenuating DMS emissions are in turn driven by the light dose received by the pelagic ecosystem.

  19. Atmospheric Aerosol Emissions Related to the Mediterranean Seawater Biogeochemistry

    Science.gov (United States)

    Sellegri, K.; Schwier, A.; Rose, C.; Gazeau, F. P. H.; Guieu, C.; D'anna, B.; Ebling, A. M.; Pey, J.; Marchand, N.; Charriere, B.; Sempéré, R.; Mas, S.

    2016-02-01

    Marine aerosols contribute significantly to the global aerosol load and consequently has an important impact on the Earth's climate. Different factors influence the way they are produced at the air/seawater interface. The sea state (whitecap coverage, temperature, etc. ) influence the size and concentration of primarily produced particles but also biogeochemical characteristics of the seawater influence both the physical and chemical primary fluxes to the atmosphere. An additional aerosol source of marine aerosol to the atmosphere is the formation of new particles by gaz-to-particle conversion, i.e. nucleation. How the seawater and surface microlayer biogeochemical compositions influences the aerosol emissions is still a large debate. In order to study marine emissions, one approach is to use semi-controlled environments such as mesocosms. Within the MedSea and SAM projects, we characterize the primary Sea Spray Aerosol (SSA) during mesocosms experiments performed during different seasons in the Mediteranean Sea. Mesocosms were either left unchanged as control or enriched by addition of nutriments in order to create different levels of phytoplanctonic activities. The mesocosms waters were daily analyzed for their chemical and biological composition (DOC, CDOM, TEP, Chl-a, virus, bacteria, phytoplankton and zooplankton concentrations). SSA production by bubble bursting was daily simulated in a dedicated set-up. The size segregated SSA number fluxes, cloud condensation nuclei (CCN) properties, and chemical composition were determined as a function of the seawater characteristics. We show that the SSA organic content was clearly correlated to the seawater Chl-a level, provided that the mesocosm was not enriched to create an artificial phytoplanctonic bloom. In our experiments, the enrichment of the seawater with natural surface microlayer did not impact the SSA organic content nor its CCN properties. At last, nucleation of secondary particles were observed to occur in

  20. Winter evolution of DMS and DMSP in Venice lagoon water and sediment.

    Science.gov (United States)

    Gambaro, Andrea; Moret, Ivo; Piazza, Rossano; Da Rin, Eleonora; Turetta, Clara; Cescon, Paolo

    2002-03-01

    The evolution of dimethylsulphide (DMS) and dimethylsulphoniopropionate (DMSP) concentrations in the water and sediment of the Venice lagoon were studied together with the concentration of chlorophyll a, temperature and the composition and density of phytoplankton to understand the role of the sediment as a source of DMS during the winter period. The temporal trend of water DMS concentration in this period showed a maximum concentration in February (75.7 nmol S l-1) related to low DMSP and chlorophyll a concentrations but to high phytoplanktonic abundance. The DMS and DMSP concentrations were greater in the sediment than in the water. The temporal trend of DMS concentration in sediment showed a maximum in February (1155 nmol S l-1) related to the maximum of DMS concentration in surface water. These observations suggested that in the winter period DMS could be produced by the conversion of the DMSP present in the bulk water but principally by that present in the sediment (microbiological degradation of DMSP or other sulphur-containing compounds) that subsequently diffuse in water.

  1. Different Planctomycetes diversity patterns in latitudinal surface seawater of the open sea and in sediment.

    Science.gov (United States)

    Shu, Qinglong; Jiao, Nianzhi

    2008-04-01

    The 16S rRNA gene approach was applied to investigate the diversity of Planctomycetes in latitudinal surface seawater of the Western Pacific Ocean. The results revealed that the Pirellula-Rhodopirellula-Blastopirellula clade dominated the Planctomycetes community at all surface seawater sites while the minority genera Gemmata and Planctomyces were only found at sites H5 and H2 respectively. Although the clone frequency of the PRB clade seemed stable (between 83.3% and 94.1%) for all surface seawater sites, the retrieved Pirellula-Rhodopirellula-Blastopirellula clade presented unexpected diversity. Interestingly, low latitude seawater appeared to have higher diversity than mid-latitudes. integral-LIBSHUFF software analysis revealed significantly different diversity patterns between in latitudinal surface seawater and in the sediment of South China Sea station M2896. Our data suggested that different hydrological and geographic features contributed to the shift of Planctomycetes diversity in marine environments. This is, to our knowledge, the first systematic assessment of Planctomycetes in latitudinal surface seawater of the open sea and the first comparison of diversity pattern between surface seawater and sediments and has broadened our understanding of Planctomycetes diversity in marine environments.

  2. Ability of possible DMS precursors to release DMS during wine aging and in the conditions of heat-alkaline treatment.

    Science.gov (United States)

    Segurel, Marie A; Razungles, Alain J; Riou, Christophe; Trigueiro, Mafalda G L; Baumes, Raymond L

    2005-04-06

    The origin of dimethyl sulfide (DMS) produced during wine aging was examined through different assays. The production of DMS during the model aging of a wine and the concomitant decrease of residual potential DMS (PDMS), as DMS released by heat-alkaline treatment in 0.5 M sodium hydroxide at 100 degrees C for 1 h, were demonstrated. Then, dimethyl sulfoxide (DMSO), methionine sulfoxide (MSO), S-methylmethionine (SMM), and dimethylsulfonium propanoic acid (DMSPA), reported previously as possible DMS precursors, were investigated for their ability to be DMS precursors in wine in the conditions of this model aging and of the heat-alkaline treatment. The results showed that DMSO, MSO, and DMSPA could hardly be DMS precursors in the conditions used, whereas SMM appeared to be a good candidate. Finally, the use of [(2)H(6)]-DMSPA as an internal standard for PDMS determination was proposed, because it provided better reproducibility than [(2)H(6)]-DMS used as an external standard.

  3. Monitoring/Verification Using DMS: TATP Example

    International Nuclear Information System (INIS)

    Kevin Kyle; Stephan Weeks

    2008-01-01

    Field-rugged and field-programmable differential mobility spectrometry (DMS) networks provide highly selective, universal monitoring of vapors and aerosols at detectable levels from persons or areas involved with illicit chemical/biological/explosives (CBE) production. CBE sensor motes used in conjunction with automated fast gas chromatography with DMS detection (GC/DMS) verification instrumentation integrated into situational operations management systems can be readily deployed and optimized for changing application scenarios. The feasibility of developing selective DMS motes for a 'smart dust' sampling approach with guided, highly selective, fast GC/DMS verification analysis is a compelling approach to minimize or prevent the illegal use of explosives or chemical and biological materials. DMS is currently one of the foremost emerging technologies for field separation and detection of gas-phase chemical species. This is due to trace-level detection limits, high selectivity, and small size. GC is the leading analytical method for the separation of chemical species in complex mixtures. Low-thermal-mass GC columns have led to compact, low-power field systems capable of complete analyses in 15-300 seconds. A collaborative effort optimized a handheld, fast GC/DMS, equipped with a non-rad ionization source, for peroxide-based explosive measurements

  4. An updated climatology of surface dimethlysulfide concentrations and emission fluxes in the global ocean

    Science.gov (United States)

    Lana, A.; Bell, T. G.; Simó, R.; Vallina, S. M.; Ballabrera-Poy, J.; Kettle, A. J.; Dachs, J.; Bopp, L.; Saltzman, E. S.; Stefels, J.; Johnson, J. E.; Liss, P. S.

    2011-03-01

    The potentially significant role of the biogenic trace gas dimethylsulfide (DMS) in determining the Earth's radiation budget makes it necessary to accurately reproduce seawater DMS distribution and quantify its global flux across the sea/air interface. Following a threefold increase of data (from 15,000 to over 47,000) in the global surface ocean DMS database over the last decade, new global monthly climatologies of surface ocean DMS concentration and sea-to-air emission flux are presented as updates of those constructed 10 years ago. Interpolation/extrapolation techniques were applied to project the discrete concentration data onto a first guess field based on Longhurst's biogeographic provinces. Further objective analysis allowed us to obtain the final monthly maps. The new climatology projects DMS concentrations typically in the range of 1-7 nM, with higher levels occurring in the high latitudes, and with a general trend toward increasing concentration in summer. The increased size and distribution of the observations in the DMS database have produced in the new climatology substantially lower DMS concentrations in the polar latitudes and generally higher DMS concentrations in regions that were severely undersampled 10 years ago, such as the southern Indian Ocean. Using the new DMS concentration climatology in conjunction with state-of-the-art parameterizations for the sea/air gas transfer velocity and climatological wind fields, we estimate that 28.1 (17.6-34.4) Tg of sulfur are transferred from the oceans into the atmosphere annually in the form of DMS. This represents a global emission increase of 17% with respect to the equivalent calculation using the previous climatology. This new DMS climatology represents a valuable tool for atmospheric chemistry, climate, and Earth System models.

  5. Spectroscopic study of the reaction between Br2 and dimethyl sulfide (DMS), and comparison with a parallel study made on Cl2 + DMS: possible atmospheric implications.

    Science.gov (United States)

    Beccaceci, Sonya; Ogden, J Steven; Dyke, John M

    2010-03-07

    The reaction between molecular bromine and dimethyl sulfide (DMS) has been studied both as a co-condensation reaction in low temperature matrices by infrared (IR) matrix isolation spectroscopy and in the gas-phase at low pressures by UV photoelectron spectroscopy (PES). The co-condensation reaction leads to the formation of the molecular van der Waals adduct DMS-Br(2). This was identified by IR spectroscopy supported by results of electronic structure calculations. Calculation of the minimum energy structures in important regions of the reaction surface and computed IR spectra of these structures, which could be compared with the experimental spectra, allowed the structure of the adduct (C(s)) to be determined. The low pressure (ca. 10(-5) mbar) gas-phase reaction was studied by UV-PES, but did not yield any observable products, indicating that a third body is necessary for the adduct to be stabilised. These results are compared with parallel co-condensation and gas-phase reactions between DMS and Cl(2). For this reaction, a similar van der Waals adduct DMS-Cl(2) is observed by IR spectroscopy in the co-condensation reactions, but in the gas-phase, this adduct converts to a covalently bound structure Me(2)SCl(2), observed in PES studies, which ultimately decomposes to monochlorodimethylsulfide and HCl. For these DMS + X(2) reactions, computed relative energies of minima and transition states on the potential energy surfaces are presented which provide an interpretation for the products observed from the two reactions studied. The implications of the results obtained to atmospheric chemistry are discussed.

  6. Distribution of 137Cs in surface seawater and sediment around Sabahs Sulu-Sulawesi Sea

    International Nuclear Information System (INIS)

    Mohd Izwan Abdul Aziz; Ahmad Sanadi Abu Bakar; Yii, Mei Wo; Nurrul Assyikeen Jaffary; Zaharudin Ahmad

    2010-01-01

    The studies on distribution of 137 Cs in surface seawater and sediment around Sabahs Sulu-Sulawesi Sea were carried out during Ekspedisi Pelayaran Saintifik Perdana (EPSP) in July 2009. About sixteen and twenty five sampling locations were identified for surface seawater and sediment respectively in Sabahs Sulu-Sulawesi Sea. Large volumes of seawater samples are collected and co-precipitation technique was employed to concentrate cesium content before known amounts of 134 Cs tracer were added as yield determinant. Grab sampler were used to collect surface sediment sample. The caesium precipitate and sediment were dried and finely ground before counted using gamma-ray spectrometry system at 661 keV. The activity of 137 Cs was found in surface seawater and sediment to be in the range 1.73 Bq/ m 3 to 5.50 Bq/ m 3 and 1.15 Bq/ kg to 4.53 Bq/ kg respectively. (author)

  7. Assessment of a global climatology of oceanic dimethylsulfide (DMS) concentrations based on SeaWiFS imagery (1998-2001)

    NARCIS (Netherlands)

    Belviso, S; Moulin, C; Bopp, L; Stefels, J

    A method is developed to estimate sea-surface particulate dimethylsulfoniopropionate (DMSP(p)) and dimethylsulfide (DMS) concentrations from sea-surface concentrations of chlorophyll a (Chl a). When compared with previous studies, the 1degrees x 1degrees global climatology of oceanic DMS

  8. Determination of 226Ra and 228Ra in surface seawater around Sagami bay and its vicinity

    International Nuclear Information System (INIS)

    Nakano-Ohta, T.; Kubota, T.; Mahara, Y.; Yoshikawa, M.; Sato, J.

    2006-01-01

    Activity ratios of 228 Ra/ 226 Ra in surface seawaters were observed at 5 ports of Izu-Oshima, Ajiro port of Sagami bay and Umizuri park of Tokyo bay. The 228 Ra/ 226 Ra activity ratio in surface seawaters were from 0.2 to 0.7 for Izu-Oshima, from 0.2 to 0.7 for Ajiro port and from 0.6 to 0.8 for Tokyo bay. The activity ratio in surface seawaters of Izu-Oshima and Atami of Sagami bay showed lower in spring and highly in autumn, while narrow variation pattern was observed in Umizuri park of Tokyo bay. The observed variation patterns of 228 Ra/ 226 Ra in surface seawaters at Izu-oshima, Ajiro park and Umizuri park may be reflected by difference of contribution from amount of seawater far off coast with low 228 Ra concentration. (author)

  9. An updated climatology of surface dimethlysulfide concentrations and emission fluxes in the global ocean

    NARCIS (Netherlands)

    Lana, A.; Bell, T. G.; Simo, R.; Vallina, S. M.; Ballabrera-Poy, J.; Kettle, A. J.; Dachs, J.; Bopp, L.; Saltzman, E. S.; Stefels, J.; Johnson, J. E.; Liss, P. S.

    2011-01-01

    The potentially significant role of the biogenic trace gas dimethylsulfide (DMS) in determining the Earth's radiation budget makes it necessary to accurately reproduce seawater DMS distribution and quantify its global flux across the sea/air interface. Following a threefold increase of data (from

  10. Perception of dimethyl sulfide (DMS) by loggerhead sea turtles: a possible mechanism for locating high-productivity oceanic regions for foraging.

    Science.gov (United States)

    Endres, Courtney S; Lohmann, Kenneth J

    2012-10-15

    During their long-distance migrations, sea turtles of several species feed on jellyfish and other invertebrates that are particularly abundant in ocean regions characterized by high productivity. An ability to distinguish productive oceanic regions from other areas, and to concentrate foraging activities in locations where prey density is highest, might therefore be adaptive. The volatile compound dimethyl sulfide (DMS) accumulates in the air above productive ocean areas such as upwelling and frontal zones. In principle, DMS might therefore serve as an indicator of high prey density for turtles. To determine whether turtles perceive DMS, juvenile loggerhead sea turtles (Caretta caretta) were placed into a water-filled arena in which DMS and other odorants could be introduced to the air above the water surface. Turtles exposed to air that had passed over a cup containing 10 nmol l(-1) DMS spent more time at the surface with their noses out of the water than control turtles, which were exposed to air that had passed over a cup containing distilled water. Odors that do not occur in the sea (cinnamon, jasmine and lemon) did not elicit increased surface time, implying that the response to DMS is unlikely to reflect a generalized response to any novel odor. The results demonstrate for the first time that sea turtles can detect DMS, an ability that might enable the identification of favorable foraging areas.

  11. Biogeochemistry of Dimethylsulfide, Dimethylsulfoniopropionate, and Acrylic Acid in the Changjiang Estuary and the East China Sea

    Science.gov (United States)

    Wu, Xi; Li, Pei-Feng; Liu, Chun-Ying; Zhang, Hong-Hai; Yang, Gui-Peng; Zhang, Sheng-Hui; Zhu, Mao-Xu

    2017-12-01

    The distributions of dimethylsulfide (DMS), dimethylsulfoniopropionate (DMSP), and acrylic acid (AA) were investigated in the Changjiang Estuary during winter (dry season) and summer (wet season) 2014 and in the East China Sea (ECS) during summer 2015. The rates of dissolved DMSP (DMSPd) degradation with DMS and AA production, DMS degradation, and AA degradation in the ECS were also studied. Significant seasonal variations in DMS(P) and AA concentrations were observed in the Changjiang Estuary with higher values during the wet season than during the dry season. The maximum ratio of AA/chlorophyll a (Chl a) occurred at the mouth of the Changjiang Estuary due to the combined effects of production from DMSP and terrestrial inputs from the Changjiang Estuary. The distributions of DMS(P) and AA in the ECS were dramatically influenced by the Kuroshio Current and the upwelling caused by the Taiwan Warm Current. The ratios of DMS(P)/Chl a and AA/Chl a exhibited similar patterns in the surface seawater of the ECS, which indicated that phytoplankton species and biomass might play important roles in controlling the distributions of DMS(P) and AA. In vertical profiles, high values of AA emerged in the upper water column and bottom seawater of the Changjiang Estuary. Meanwhile, the maxima of DMS(P) and AA generally appeared in the surface or euphotic layer, whereas their minima arose in the bottom seawater of the ECS. The degradation rates of DMSPd, DMS, and AA in the inshore waters were higher than those in the open sea.

  12. The contribution of ocean-leaving DMS to the global atmospheric burdens of DMS, MSA, SO2, and NSS SO4=

    NARCIS (Netherlands)

    van Himbergen-Gondwe, P.M.; Krol, M.; Gieskes, W.W C; Klaassen, W.; de Baar, H.J.W.

    2003-01-01

    [1] The contribution of ocean-derived DMS to the atmospheric burdens of a variety of sulphur compounds (DMS, MSA, SO2, and nss SO4=) is quantified from season to season. Such quantification, especially for nss SO4= (the climate-relevant product of DMS oxidation), is essential for the quantification

  13. Dimethylsulphide (DMS emissions from the western Pacific Ocean: a potential marine source for stratospheric sulphur?

    Directory of Open Access Journals (Sweden)

    C. A. Marandino

    2013-08-01

    Full Text Available Sea surface and atmospheric measurements of dimethylsulphide (DMS were performed during the TransBrom cruise in the western Pacific Ocean between Japan and Australia in October 2009. Air–sea DMS fluxes were computed between 0 and 30 μmol m−2 d−1, which are in agreement with those computed by the current climatology, and peak emissions of marine DMS into the atmosphere were found during the occurrence of tropical storm systems. Atmospheric variability in DMS, however, did not follow that of the computed fluxes and was more related to atmospheric transport processes. The computed emissions were used as input fields for the Lagrangian dispersion model FLEXPART, which was set up with actual meteorological fields from ERA-Interim data and different chemical lifetimes of DMS. A comparison with aircraft in situ data from the adjacent HIPPO2 campaign revealed an overall good agreement between modelled versus observed DMS profiles over the tropical western Pacific Ocean. Based on observed DMS emissions and meteorological fields along the cruise track, the model projected that up to 30 g S per month in the form of DMS, emitted from an area of 6 × 104 m2, can be transported above 17 km. This surprisingly large DMS entrainment into the stratosphere is disproportionate to the regional extent of the area of emissions and mainly due to the high convective activity in this region as simulated by the transport model. Thus, if DMS can cross the tropical tropopause layer (TTL, we suggest that the considerably larger area of the tropical western Pacific Ocean can be a source of sulphur to the stratosphere, which has not been considered as yet.

  14. MT3DMS: Model use, calibration, and validation

    Science.gov (United States)

    Zheng, C.; Hill, Mary C.; Cao, G.; Ma, R.

    2012-01-01

    MT3DMS is a three-dimensional multi-species solute transport model for solving advection, dispersion, and chemical reactions of contaminants in saturated groundwater flow systems. MT3DMS interfaces directly with the U.S. Geological Survey finite-difference groundwater flow model MODFLOW for the flow solution and supports the hydrologic and discretization features of MODFLOW. MT3DMS contains multiple transport solution techniques in one code, which can often be important, including in model calibration. Since its first release in 1990 as MT3D for single-species mass transport modeling, MT3DMS has been widely used in research projects and practical field applications. This article provides a brief introduction to MT3DMS and presents recommendations about calibration and validation procedures for field applications of MT3DMS. The examples presented suggest the need to consider alternative processes as models are calibrated and suggest opportunities and difficulties associated with using groundwater age in transport model calibration.

  15. Standard practice for exposing and evaluating metals and alloys in surface seawater

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2000-01-01

    1.1 This practice covers conditions for the exposure of metals, alloys, and other materials in natural surface seawater such as those typically found in bays, harbors, channels, and so forth, as contrasted with deep ocean testing. This practice covers full immersion, tidal zone and related splash, and spray zone exposures. 1.2 This practice sets forth general procedures that should be followed in conducting seawater exposure tests so that meaningful comparisons may be made from one location to another. 1.3 This practice identifies recommended procedures for evaluating the effects of natural surface seawater on the materials exposed. 1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regula...

  16. Monitoring/Verification using DMS: TATP Example 8422

    International Nuclear Information System (INIS)

    Stephan Weeks; Kevin Kyle

    2008-01-01

    Field-rugged and field-programmable differential mobility spectrometry (DMS) networks provide highly selective, universal monitoring of vapors and aerosols at detectable levels from persons or areas involved with illicit chemical/biological/explosives (CBE) production. CBE sensor motes used in conjunction with automated fast gas chromatography with DMS detection (GC/DMS) verification instrumentation integrated into situational operations management systems can be readily deployed and optimized for changing application scenarios. The feasibility of developing selective DMS motes for a 'smart dust' sampling approach with guided, highly selective, fast GC/DMS verification analysis is a compelling approach to minimize or prevent the use of explosives or chemical and biological weapons in terrorist activities. Two peroxide-based liquid explosives, triacetone triperoxide (TATP) and hexamethylene triperoxide diamine (HMTD), are synthesized from common chemicals such as hydrogen peroxide, acetone, sulfuric acid, ammonia, and citric acid (Figure 1). Recipes can be readily found on the Internet by anyone seeking to generate sufficient quantities of these highly explosive chemicals to cause considerable collateral damage. Detection of TATP and HMTD by advanced sensing systems can provide the early warning necessary to prevent terror plots from coming to fruition. DMS is currently one of the foremost emerging technologies for the separation and detection of gas-phase chemical species. This is due to trace-level detection limits, high selectivity, and small size. DMS separates and identifies ions at ambient pressures by utilizing the non-linear dependence of an ion's mobility on the radio frequency (rf) electric field strength. GC is widely considered to be one of the leading analytical methods for the separation of chemical species in complex mixtures. Advances in the technique have led to the development of low-thermal-mass fast GC columns. These columns are capable of

  17. Waste Receiving and Processing Facility PMS Test Report/DMS-Y2K/System Security DMS (Data Management System)

    International Nuclear Information System (INIS)

    PALMER, M.E.

    1999-01-01

    Test Plan HNF-4351 defines testing requirements for installation of a new server in the WRAP Facility. This documents shows the results of the test reports on the DMS-Y2K and DMS-F81 (Security) systems

  18. CDOM Sources and Photobleaching Control Quantum Yields for Oceanic DMS Photolysis

    KAUST Repository

    Galí, Martí

    2016-11-14

    Photolysis is a major removal pathway for the biogenic gas dimethylsulfide (DMS) in the surface ocean. Here we tested the hypothesis that apparent quantum yields (AQY) for DMS photolysis varied according to the quantity and quality of its photosensitizers, chiefly chromophoric dissolved organic matter (CDOM) and nitrate. AQY compiled from the literature and unpublished studies ranged across 3 orders of magnitude at the 330 nm reference wavelength. The smallest AQY(330) were observed in coastal waters receiving major riverine inputs of terrestrial CDOM (0.06-0.5 m3 (mol quanta)-1). In open-ocean waters, AQY(330) generally ranged between 1 and 10 m3 (mol quanta)-1. The largest AQY(330), up to 34 m3 (mol quanta)-1), were seen in the Southern Ocean potentially associated with upwelling. Despite the large AQY variability, daily photolysis rate constants at the sea surface spanned a smaller range (0.04-3.7 d-1), mainly because of the inverse relationship between CDOM absorption and AQY. Comparison of AQY(330) with CDOM spectral signatures suggests there is an interplay between CDOM origin (terrestrial versus marine) and photobleaching that controls variations in AQYs, with a secondary role for nitrate. Our results can be used for regional or large-scale assessment of DMS photolysis rates in future studies.

  19. CDOM Sources and Photobleaching Control Quantum Yields for Oceanic DMS Photolysis.

    Science.gov (United States)

    Galí, Martí; Kieber, David J; Romera-Castillo, Cristina; Kinsey, Joanna D; Devred, Emmanuel; Pérez, Gonzalo L; Westby, George R; Marrasé, Cèlia; Babin, Marcel; Levasseur, Maurice; Duarte, Carlos M; Agustí, Susana; Simó, Rafel

    2016-12-20

    Photolysis is a major removal pathway for the biogenic gas dimethylsulfide (DMS) in the surface ocean. Here we tested the hypothesis that apparent quantum yields (AQY) for DMS photolysis varied according to the quantity and quality of its photosensitizers, chiefly chromophoric dissolved organic matter (CDOM) and nitrate. AQY compiled from the literature and unpublished studies ranged across 3 orders of magnitude at the 330 nm reference wavelength. The smallest AQY(330) were observed in coastal waters receiving major riverine inputs of terrestrial CDOM (0.06-0.5 m 3 (mol quanta) -1 ). In open-ocean waters, AQY(330) generally ranged between 1 and 10 m 3 (mol quanta) -1 . The largest AQY(330), up to 34 m 3 (mol quanta) -1 ), were seen in the Southern Ocean potentially associated with upwelling. Despite the large AQY variability, daily photolysis rate constants at the sea surface spanned a smaller range (0.04-3.7 d -1 ), mainly because of the inverse relationship between CDOM absorption and AQY. Comparison of AQY(330) with CDOM spectral signatures suggests there is an interplay between CDOM origin (terrestrial versus marine) and photobleaching that controls variations in AQYs, with a secondary role for nitrate. Our results can be used for regional or large-scale assessment of DMS photolysis rates in future studies.

  20. Quantification of dimethyl sulfide (DMS) production in the sea anemone Aiptasia sp. to simulate the sea-to-air flux from coral reefs

    Science.gov (United States)

    Franchini, Filippo; Steinke, Michael

    2017-12-01

    The production of dimethyl sulfide (DMS) is poorly quantified in tropical reef environments but forms an essential process that couples marine and terrestrial sulfur cycles and affects climate. Here we quantified net aqueous DMS production and the concentration of its cellular precursor dimethylsulfoniopropionate (DMSP) in the sea anemone Aiptasia sp., a model organism to study coral-related processes. Bleached anemones did not show net DMS production whereas symbiotic anemones produced DMS concentrations (mean ± standard error) of 160.7 ± 44.22 nmol g-1 dry weight (DW) after 48 h incubation. Symbiotic and bleached individuals showed DMSP concentrations of 32.7 ± 6.00 and 0.6 ± 0.19 µmol g-1 DW, respectively. We applied these findings to a Monte Carlo simulation to demonstrate that net aqueous DMS production accounts for only 20 % of gross aqueous DMS production. Monte Carlo-based estimations of sea-to-air fluxes of gaseous DMS showed that reefs may release 0.1 to 26.3 µmol DMS m-2 coral surface area (CSA) d-1 into the atmosphere with 40 % probability for rates between 0.5 and 1.5 µmol m-2 CSA d-1. These predictions were in agreement with directly quantified fluxes in previous studies. Conversion to a flux normalised to sea surface area (SSA) (range 0.1 to 17.4, with the highest probability for 0.3 to 1.0 µmol DMS m-2 SSA d-1) suggests that coral reefs emit gaseous DMS at lower rates than the average global oceanic DMS flux of 4.6 µmol m-2 SSA d-1 (19.6 Tg sulfur per year). The large difference between simulated gross and quantified net aqueous DMS production in corals suggests that the current and future potential for its production in tropical reefs is critically governed by DMS consumption processes. Hence, more research is required to assess the sensitivity of DMS-consumption pathways to ongoing environmental change in order to address the impact of predicted degradation of coral reefs on DMS production in tropical coastal ecosystems and its impact on

  1. Diversity of bacterioplankton in the surface seawaters of Drake Passage near the Chinese Antarctic station.

    Science.gov (United States)

    Xing, Mengxin; Li, Zhao; Wang, Wei; Sun, Mi

    2015-07-01

    The determination of relative abundances and distribution of different bacterial groups is a critical step toward understanding the functions of various bacteria and its surrounding environment. Few studies focus on the taxonomic composition and functional diversity of microbial communities in Drake Passage. In this study, marine bacterioplankton communities from surface seawaters at five locations in Drake Passage were examined by 16S rRNA gene sequence analyses. The results indicated that psychrophilic bacteria were the most abundant group in Drake Passage, and mainly made up of Bacillus, Aeromonas, Psychrobacter, Pseudomonas and Halomonas. Diversity analysis showed that surface seawater communities had no significant correlation with latitudinal gradient. Additionally, a clear difference among five surface seawater communities was evident, with 1.8% OTUs (only two) belonged to Bacillus consistent across five locations and 71% OTUs (80) existed in only one location. However, the few cosmopolitans had the largest population sizes. Our results support the hypothesis that the dominant bacterial groups appear to be analogous between geographical sites, but significant differences may be detected among rare bacterial groups. The microbial diversity of surface seawaters would be liable to be affected by environmental factors. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Metabolism of DMSP, DMS and DMSO by the cultivable bacterial community associated with the DMSP-producing dinoflagellate Scrippsiella trochoidea

    Digital Repository Service at National Institute of Oceanography (India)

    Hatton, A.D.; Shenoy, D.M.; Hart, M.C.; Mogg, A.; Green, D.H.

    populations in the Sargasso Sea (del Valle et al. 2007), North Sea (Zubkov et al. 2002) and Gulf of Mexico (Vila-Costa et al. 2006). Instead, there is now a body of evidence, which supports the hypothesis that DMS oxidation to DMSO may be the major pathway... of Mexico. Limnol Oceanogr 45(4):849–861 Kiene RP, Linn LJ (2000b) The fate of dissolved dimethylsulfoniopropionate (DMSP) in seawater: tracer studies using 35S-DMSP. Geochim Cosmochim Acta 64(16):2797–2810 Kiene RP, Linn LJ, Bruton JA (2000) New...

  3. Diversity of bacterial dimethylsulfoniopropionate degradation genes in surface seawater of Arctic Kongsfjorden.

    Science.gov (United States)

    Zeng, Yin-Xin; Qiao, Zong-Yun; Yu, Yong; Li, Hui-Rong; Luo, Wei

    2016-09-08

    Dimethylsulfoniopropionate (DMSP), which is the major source of organic sulfur in the world's oceans, plays a significant role in the global sulfur cycle. This compound is rapidly degraded by marine bacteria either by cleavage to dimethylsulfide (DMS) or demethylation to 3-methylmercaptopropionate (MMPA). The diversity of genes encoding bacterial demethylation (dmdA) and DMS production (dddL and dddP) were measured in Arctic Kongsfjorden. Both dmdA and dddL genes were detected in all stations along a transect from the outer to the inner fjord, while dddP gene was only found in the outer and middle parts of the fjord. The dmdA gene was completely confined to the Roseobacter clade, while the dddL gene was confined to the genus Sulfitobacter. Although the dddP gene pool was also dominated by homologs from the Roseobacter clade, there were a few dddP genes showing close relationships to both Alphaproteobacter and Gammaproteobacter. The results of this study suggest that the Roseobacter clade may play an important role in DMSP catabolism via both demethylation and cleavage pathways in surface waters of Kongsfjorden during summer.

  4. Tc(V)-DMS tumor localization mechanism: a pH-sensitive Tc(V)-DMS-enhanced target/nontarget ratio by glucose-mediated acidosis

    International Nuclear Information System (INIS)

    Horiuchi, Kazuko; Saji, Hideo; Yokoyama, Akira

    1998-01-01

    Since the conception of the pentavalent technetium polynuclear complex of dimercaptosuccinic acid, Tc(V)-DMS, a great number of papers published on its clinical applicability forced us to question ''how tumor tissue appropriates the Tc(V)-DMS.'' Preliminary in vitro studies with Ehrlich ascites tumor cells (EATC) indicated the pH-sensitive character of this tumor agent. From this finding and the well-established notion that malignant tumors are more acidic than normal tissue, the in vivo correlation of Tc(V)-DMS accumulation in tumor tissue with its tissue acidification was considered of interest. The systemic lowering of tumor tissue pH by the stimulation of aerobic glycolysis has been well reported. In the present paper, the response of Tc(V)-DMS tumor accumulation to acidification induced by the glucose administration was explored in EATC-bearing mice. Measurement of tumor tissue pH was carried out by direct microelectrode technique and by histochemical umbelliferone technique in tumor tissue excised from EATC bearing mice. The regional acidity distribution is correlated with the regional radioactivity distribution registered by autoradiography. Evidence related to the pH sensitiveness of Tc(V)-DMS in response to glycolytic acidification was gathered; the pH measurement and the in vivo biodistribution of the double-tracer macroautoradiography with C-14 deoxyglucose (C-14-DG) demonstrated that the regional tissue distribution of Tc(V)-DMS was superimposed to that of C-14-DG. The glucose interventional modality offers the premier foundation for the interpretation of Tc(V)-DMS accumulation in diagnostic studies of malignant tumors

  5. Waste Receiving and Processing (WRAP) Facility PMS Test Report For Data Management System (DMS) Security Test DMS-Y2K

    Energy Technology Data Exchange (ETDEWEB)

    PALMER, M.E.

    1999-09-21

    Test Plan HNF-4351 defines testing requirements for installation of a new server in the WRAP Facility. This document shows the results of the test reports on the DMS-Y2K and DMS-F81 (Security) systems.

  6. Quantification of dimethyl sulfide (DMS production in the sea anemone Aiptasia sp. to simulate the sea-to-air flux from coral reefs

    Directory of Open Access Journals (Sweden)

    F. Franchini

    2017-12-01

    Full Text Available The production of dimethyl sulfide (DMS is poorly quantified in tropical reef environments but forms an essential process that couples marine and terrestrial sulfur cycles and affects climate. Here we quantified net aqueous DMS production and the concentration of its cellular precursor dimethylsulfoniopropionate (DMSP in the sea anemone Aiptasia sp., a model organism to study coral-related processes. Bleached anemones did not show net DMS production whereas symbiotic anemones produced DMS concentrations (mean ± standard error of 160.7 ± 44.22 nmol g−1 dry weight (DW after 48 h incubation. Symbiotic and bleached individuals showed DMSP concentrations of 32.7 ± 6.00 and 0.6 ± 0.19 µmol g−1 DW, respectively. We applied these findings to a Monte Carlo simulation to demonstrate that net aqueous DMS production accounts for only 20 % of gross aqueous DMS production. Monte Carlo-based estimations of sea-to-air fluxes of gaseous DMS showed that reefs may release 0.1 to 26.3 µmol DMS m−2 coral surface area (CSA d−1 into the atmosphere with 40 % probability for rates between 0.5 and 1.5 µmol m−2 CSA d−1. These predictions were in agreement with directly quantified fluxes in previous studies. Conversion to a flux normalised to sea surface area (SSA (range 0.1 to 17.4, with the highest probability for 0.3 to 1.0 µmol DMS m−2 SSA d−1 suggests that coral reefs emit gaseous DMS at lower rates than the average global oceanic DMS flux of 4.6 µmol m−2 SSA d−1 (19.6 Tg sulfur per year. The large difference between simulated gross and quantified net aqueous DMS production in corals suggests that the current and future potential for its production in tropical reefs is critically governed by DMS consumption processes. Hence, more research is required to assess the sensitivity of DMS-consumption pathways to ongoing environmental change in order to address the impact of predicted

  7. Distribution of radionuclides in surface seawater obtained by an aerial radiological survey

    International Nuclear Information System (INIS)

    Inomata, Yayoi; Aoyama, Michio; Hirose, Katsumi; Sanada, Yukihisa; Torii, Tatsuo; Tsubono, Takaki; Tsumune, Daisuke; Yamada, Masatoshi

    2014-01-01

    We investigated the distribution in seawater of anthropogenic radionuclides from the Fukushima Daiichi Nuclear Power Plant (FNPP1) as preliminary attempt using a rapid aerial radiological survey performed by the U.S. Department of Energy National Nuclear Security Administration on 18 April 2011. We found strong correlations between in-situ activities of 131 I, 134 Cs, and 137 Cs measured in surface seawater samples and gamma-ray peak count rates determined by the aerial survey (correlation coefficients were 0.89 for 131 I, 0.96 for 134 Cs, and 0.92 for 137 Cs). The offshore area of high radionuclide activity extended south and southeast from the FNPP1. The maximum activities of 131 I, 134 Cs, and 137 Cs were 329, 650, and 599 Bq L -1 , respectively. The 131 I/ 137 Cs ratio in surface water of the high-activity area ranged from 0.6 to 0.7. Considering the radioactive decay of 131 I (half-life 8.02 d), we determined that the radionuclides in this area were directly released from FNPP1 to the ocean. We confirm that aerial radiological surveys can be effective for investigating the surface distribution of anthropogenic radionuclides in seawater. Our model reproduced the distribution pattern of radionuclides derived from the FNPP1, although results simulated by a regional ocean model were underestimated. (author)

  8. Impacts of Marine Ecodynamics on the Dimethyl Sulfide(DMS) Production

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shanlin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Maltrud, Mathew Einar [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Elliott, Scott M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Cameron-Smith, Philip [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-11-05

    Given the new explicit Phaeocystis representation, the DMS distribution shows significant improvements, especially regarding the amplitude and location of high latitude peaks. The production of DMS varies with climate. It is therefore necessary to couple the dynamics DMS module in climate projections.

  9. Increase in dimethylsulfide (DMS emissions due to eutrophication of coastal waters offsets their reduction due to ocean acidification.

    Directory of Open Access Journals (Sweden)

    Nathalie eGypens

    2014-04-01

    Full Text Available Available information from manipulative experiments suggested that the emission of dimethylsulfide (DMS would decrease in response to the accumulation of anthropogenic CO2 in the ocean (ocean acidification. However, in coastal environments, the carbonate chemistry of surface waters was also strongly modified by eutrophication and related changes in biological activity (increased primary production and change in phytoplankton dominance during the last 50 years. Here, we tested the hypothesis that DMS emissions in marine coastal environments also strongly responded to eutrophication in addition to ocean acidification at decadal timescales. We used the R-MIRO-BIOGAS model in the eutrophied Southern Bight of the North Sea characterized by intense blooms of Phaeocystis that are high producers of dimethylsulfoniopropionate (DMSP, the precursor of DMS. We showed that, for the period from 1951 to 2007, eutrophication actually led to an increase of DMS emissions much stronger than the response of DMS emissions to ocean acidification.

  10. Environmental, biochemical and genetic drivers of DMSP degradation and DMS production in the Sargasso Sea.

    Science.gov (United States)

    Levine, Naomi Marcil; Varaljay, Vanessa A; Toole, Dierdre A; Dacey, John W H; Doney, Scott C; Moran, Mary Ann

    2012-05-01

    Dimethylsulfide (DMS) is a climatically relevant trace gas produced and cycled by the surface ocean food web. Mechanisms driving intraannual variability in DMS production and dimethylsulfoniopropionate (DMSP) degradation in open-ocean, oligotrophic regions were investigated during a 10-month time-series at the Bermuda Atlantic Time-series Study site in the Sargasso Sea. Abundance and transcription of bacterial DMSP degradation genes, DMSP lyase enzyme activity, and DMS and DMSP concentrations, consumption rates and production rates were quantified over time and depth. This interdisciplinary data set was used to test current hypotheses of the role of light and carbon supply in regulating upper-ocean sulfur cycling. Findings supported UV-A-dependent phytoplankton DMS production. Bacterial DMSP degraders may also contribute significantly to DMS production when temperatures are elevated and UV-A dose is moderate, but may favour DMSP demethylation under low UV-A doses. Three groups of bacterial DMSP degraders with distinct intraannual variability were identified and niche differentiation was indicated. The combination of genetic and biochemical data suggest a modified 'bacterial switch' hypothesis where the prevalence of different bacterial DMSP degradation pathways is regulated by a complex set of factors including carbon supply, temperature and UV-A dose. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  11. Isolation and characterization of dimethyl sulfide (DMS)-degrading bacteria from soil and biofilter treating waste gas containing DMS from the laboratory and pulp and paper industry.

    Science.gov (United States)

    Giri, Balendu Shekher; Juwarkar, Asha A; Satpute, D B; Mudliar, S N; Pandey, R A

    2012-07-01

    Dimethyl sulfide (DMS) is one of the sulfurous pollutants present in the waste gas generated from the pulp and paper industry. DMS has environmental health implications; therefore, it is necessary to treat the waste gas containing DMS prior to discharge into the environment. A bench-scale biofilter was operated in the laboratory as well as in a pulp and paper industry for the treatment of DMS. Both the biofilters were packed with pre-sterilized wood chips and cow dung/compost of the same origin seeded with biomass developed from garden soil enriched with DMS. The biofilters were operated for the generation of process parameters, and the potential microorganisms isolated from both the biofilters have been purified and characterized for degradation of DMS. Further, these cultures were purified on a basal medium using DMS as a sole carbon source for the growth. Further, the purified cultures were characterized through standard fatty acid methyl esters (FAME)-gas chromatography method, and the isolates were found to be mesophilic, aerobic microbes. These microbes were identified as Bacillus sphaericus-GC subgroup F, Paenibacillus polymyxa, B. sphaericus-GC subgroup F, B. sphaericus-GC subgroup F, and Bacillus megaterium-GC subgroup A, respectively. The potential culture for degradation of DMS was identified as B. sphaericus by 16s rRNA molecular analysis.

  12. Concentrations and activity ratios of 228Ra and 226Ra in surface seawater along the Pacific coast of Japan

    International Nuclear Information System (INIS)

    Ohta, T.; Mahara, Y.; Kubota, T.; Sato, J.; Gamo, T.

    2011-01-01

    We measured the 228 Ra/ 226 Ra activity ratios in surface seawater along the Pacific coast of Japan at five ports around the island of Izu-Oshima (n = 29), at Atami in Sagami Bay (n = 13), and at Umizuri Park in Tokyo Bay (n = 14). We also conducted these measurements along a transect from the open Pacific Ocean across the Kuroshio to the mouth of Tokyo Bay (n = 7). The activity ratios decreased with increasing salinity of the sampling sites. The 228 Ra/ 226 Ra activity ratios in surface seawater along the coast gradually decreased after at the end of autumn and were lowest in winter and the beginning of spring. The surface salinity along the coast decreased from summer into autumn and increased from winter to the beginning of spring. The activity ratios decreased with the increase of salinity. The variation in activity ratios at the three coastal sites is possibly caused by differing contributions of surface seawater from the Kuroshio and surrounding open ocean. The different patterns and ranges of variation in the 228 Ra/ 226 Ra activity ratios in surface seawater at Izu-Oshima, Atami, and Umizuri Park may reflect both the amount of water from the Kuroshio and vicinity, and the local bathymetry, because continental shelf sediment is the source of Ra isotopes in surface seawater. (orig.)

  13. Air exposure of coral is a significant source of dimethylsulfide (DMS) to the atmosphere.

    Science.gov (United States)

    Hopkins, Frances E; Bell, Thomas G; Yang, Mingxi; Suggett, David J; Steinke, Michael

    2016-10-31

    Corals are prolific producers of dimethylsulfoniopropionate (DMSP). High atmospheric concentrations of the DMSP breakdown product dimethylsulfide (DMS) have been linked to coral reefs during low tides. DMS is a potentially key sulfur source to the tropical atmosphere, but DMS emission from corals during tidal exposure is not well quantified. Here we show that gas phase DMS concentrations (DMS gas ) increased by an order of magnitude when three Indo-Pacific corals were exposed to air in laboratory experiments. Upon re-submersion, an additional rapid rise in DMS gas was observed, reflecting increased production by the coral and/or dissolution of DMS-rich mucus formed by the coral during air exposure. Depletion in DMS following re-submersion was likely due to biologically-driven conversion of DMS to dimethylsulfoxide (DMSO). Fast Repetition Rate fluorometry showed downregulated photosynthesis during air exposure but rapid recovery upon re-submersion, suggesting that DMS enhances coral tolerance to oxidative stress during a process that can induce photoinhibition. We estimate that DMS emission from exposed coral reefs may be comparable in magnitude to emissions from other marine DMS hotspots. Coral DMS emission likely comprises a regular and significant source of sulfur to the tropical marine atmosphere, which is currently unrecognised in global DMS emission estimates and Earth System Models.

  14. Quantitative DMS mapping for automated RNA secondary structure inference

    OpenAIRE

    Cordero, Pablo; Kladwang, Wipapat; VanLang, Christopher C.; Das, Rhiju

    2012-01-01

    For decades, dimethyl sulfate (DMS) mapping has informed manual modeling of RNA structure in vitro and in vivo. Here, we incorporate DMS data into automated secondary structure inference using a pseudo-energy framework developed for 2'-OH acylation (SHAPE) mapping. On six non-coding RNAs with crystallographic models, DMS- guided modeling achieves overall false negative and false discovery rates of 9.5% and 11.6%, comparable or better than SHAPE-guided modeling; and non-parametric bootstrappin...

  15. Amplification of global warming through pH dependence of DMS production simulated with a fully coupled Earth system model

    Science.gov (United States)

    Schwinger, Jörg; Tjiputra, Jerry; Goris, Nadine; Six, Katharina D.; Kirkevåg, Alf; Seland, Øyvind; Heinze, Christoph; Ilyina, Tatiana

    2017-08-01

    We estimate the additional transient surface warming ΔTs caused by a potential reduction of marine dimethyl sulfide (DMS) production due to ocean acidification under the high-emission scenario RCP8.5 until the year 2200. Since we use a fully coupled Earth system model, our results include a range of feedbacks, such as the response of marine DMS production to the additional changes in temperature and sea ice cover. Our results are broadly consistent with the findings of a previous study that employed an offline model set-up. Assuming a medium (strong) sensitivity of DMS production to pH, we find an additional transient global warming of 0.30 K (0.47 K) towards the end of the 22nd century when DMS emissions are reduced by 7.3 Tg S yr-1 or 31 % (11.5 Tg S yr-1 or 48 %). The main mechanism behind the additional warming is a reduction of cloud albedo, but a change in shortwave radiative fluxes under clear-sky conditions due to reduced sulfate aerosol load also contributes significantly. We find an approximately linear relationship between reduction of DMS emissions and changes in top of the atmosphere radiative fluxes as well as changes in surface temperature for the range of DMS emissions considered here. For example, global average Ts changes by -0. 041 K per 1 Tg S yr-1 change in sea-air DMS fluxes. The additional warming in our model has a pronounced asymmetry between northern and southern high latitudes. It is largest over the Antarctic continent, where the additional temperature increase of 0.56 K (0.89 K) is almost twice the global average. We find that feedbacks are small on the global scale due to opposing regional contributions. The most pronounced feedback is found for the Southern Ocean, where we estimate that the additional climate change enhances sea-air DMS fluxes by about 9 % (15 %), which counteracts the reduction due to ocean acidification.

  16. Amplification of global warming through pH dependence of DMS production simulated with a fully coupled Earth system model

    Directory of Open Access Journals (Sweden)

    J. Schwinger

    2017-08-01

    Full Text Available We estimate the additional transient surface warming ΔTs caused by a potential reduction of marine dimethyl sulfide (DMS production due to ocean acidification under the high-emission scenario RCP8.5 until the year 2200. Since we use a fully coupled Earth system model, our results include a range of feedbacks, such as the response of marine DMS production to the additional changes in temperature and sea ice cover. Our results are broadly consistent with the findings of a previous study that employed an offline model set-up. Assuming a medium (strong sensitivity of DMS production to pH, we find an additional transient global warming of 0.30 K (0.47 K towards the end of the 22nd century when DMS emissions are reduced by 7.3 Tg S yr−1 or 31 % (11.5 Tg S yr−1 or 48 %. The main mechanism behind the additional warming is a reduction of cloud albedo, but a change in shortwave radiative fluxes under clear-sky conditions due to reduced sulfate aerosol load also contributes significantly. We find an approximately linear relationship between reduction of DMS emissions and changes in top of the atmosphere radiative fluxes as well as changes in surface temperature for the range of DMS emissions considered here. For example, global average Ts changes by −0. 041 K per 1 Tg S yr−1 change in sea–air DMS fluxes. The additional warming in our model has a pronounced asymmetry between northern and southern high latitudes. It is largest over the Antarctic continent, where the additional temperature increase of 0.56 K (0.89 K is almost twice the global average. We find that feedbacks are small on the global scale due to opposing regional contributions. The most pronounced feedback is found for the Southern Ocean, where we estimate that the additional climate change enhances sea–air DMS fluxes by about 9 % (15 %, which counteracts the reduction due to ocean acidification.

  17. WebDMS: A Web-Based Data Management System for Environmental Data

    Science.gov (United States)

    Ekstrand, A. L.; Haderman, M.; Chan, A.; Dye, T.; White, J. E.; Parajon, G.

    2015-12-01

    DMS is an environmental Data Management System to manage, quality-control (QC), summarize, document chain-of-custody, and disseminate data from networks ranging in size from a few sites to thousands of sites, instruments, and sensors. The server-client desktop version of DMS is used by local and regional air quality agencies (including the Bay Area Air Quality Management District, the South Coast Air Quality Management District, and the California Air Resources Board), the EPA's AirNow Program, and the EPA's AirNow-International (AirNow-I) program, which offers countries the ability to run an AirNow-like system. As AirNow's core data processing engine, DMS ingests, QCs, and stores real-time data from over 30,000 active sensors at over 5,280 air quality and meteorological sites from over 130 air quality agencies across the United States. As part of the AirNow-I program, several instances of DMS are deployed in China, Mexico, and Taiwan. The U.S. Department of State's StateAir Program also uses DMS for five regions in China and plans to expand to other countries in the future. Recent development has begun to migrate DMS from an onsite desktop application to WebDMS, a web-based application designed to take advantage of cloud hosting and computing services to increase scalability and lower costs. WebDMS will continue to provide easy-to-use data analysis tools, such as time-series graphs, scatterplots, and wind- or pollution-rose diagrams, as well as allowing data to be exported to external systems such as the EPA's Air Quality System (AQS). WebDMS will also provide new GIS analysis features and a suite of web services through a RESTful web API. These changes will better meet air agency needs and allow for broader national and international use (for example, by the AirNow-I partners). We will talk about the challenges and advantages of migrating DMS to the web, modernizing the DMS user interface, and making it more cost-effective to enhance and maintain over time.

  18. Rate of non-linearity in DMS aerosol-cloud-climate interactions

    Directory of Open Access Journals (Sweden)

    M. A. Thomas

    2011-11-01

    Full Text Available The degree of non-linearity in DMS-cloud-climate interactions is assessed using the ECHAM5-HAMMOZ model by taking into account end-to-end aerosol chemistry-cloud microphysics link. The evaluation is made over the Southern oceans in austral summer, a region of minimal anthropogenic influence. In this study, we compare the DMS-derived changes in the aerosol and cloud microphysical properties between a baseline simulation with the ocean DMS emissions from a prescribed climatology, and a scenario where the DMS emissions are doubled. Our results show that doubling the DMS emissions in the current climate results in a non-linear response in atmospheric DMS burden and subsequently, in SO2 and H2SO4 burdens due to inadequate OH oxidation. The aerosol optical depth increases by only ~20 % in the 30° S–75° S belt in the SH summer months. This increases the vertically integrated cloud droplet number concentrations (CDNC by 25 %. Since the vertically integrated liquid water vapor is constant in our model simulations, an increase in CDNC leads to a reduction in cloud droplet radius of 3.4 % over the Southern oceans in summer. The equivalent increase in cloud liquid water path is 10.7 %. The above changes in cloud microphysical properties result in a change in global annual mean radiative forcing at the TOA of −1.4 W m−2. The results suggest that the DMS-cloud microphysics link is highly non-linear. This has implications for future studies investigating the DMS-cloud climate feedbacks in a warming world and for studies evaluating geoengineering options to counteract warming by modulating low level marine clouds.

  19. Dimethylsulfoniopropionate (DMSP) and dimethyl sulfide (DMS) cycling across contrasting biological hotspots of the New Zealand subtropical front

    Science.gov (United States)

    Lizotte, Martine; Levasseur, Maurice; Law, Cliff S.; Walker, Carolyn F.; Safi, Karl A.; Marriner, Andrew; Kiene, Ronald P.

    2017-11-01

    The oceanic frontal region above the Chatham Rise east of New Zealand was investigated during the late austral summer season in February and March 2012. Despite its potential importance as a source of marine-originating and climate-relevant compounds, such as dimethyl sulfide (DMS) and its algal precursor dimethylsulfoniopropionate (DMSP), little is known of the processes fuelling the reservoirs of these sulfur (S) compounds in the water masses bordering the subtropical front (STF). This study focused on two opposing short-term fates of DMSP-S following its uptake by microbial organisms (either its conversion into DMS or its assimilation into bacterial biomass) and has not considered dissolved non-volatile degradation products. Sampling took place in three phytoplankton blooms (B1, B2, and B3) with B1 and B3 occurring in relatively nitrate-rich, dinoflagellate-dominated subantarctic waters, and B2 occurring in nitrate-poor subtropical waters dominated by coccolithophores. Concentrations of total DMSP (DMSPt) and DMS were high across the region, up to 160 and 14.5 nmol L-1, respectively. Pools of DMSPt showed a strong association with overall phytoplankton biomass proxied by chlorophyll a (rs = 0.83) likely because of the persistent dominance of dinoflagellates and coccolithophores, both DMSP-rich taxa. Heterotrophic microbes displayed low S assimilation from DMSP (less than 5 %) likely because their S requirements were fulfilled by high DMSP availability. Rates of bacterial protein synthesis were significantly correlated with concentrations of dissolved DMSP (DMSPd, rs = 0.86) as well as with the microbial conversion efficiency of DMSPd into DMS (DMS yield, rs = 0.84). Estimates of the potential contribution of microbially mediated rates of DMS production (0.1-27 nmol L-1 day-1) to the near-surface concentrations of DMS suggest that bacteria alone could not have sustained DMS pools at most stations, indicating an important role for phytoplankton-mediated DMS

  20. Productions of Volatile Organic Compounds (VOCs) in Surface Waters from Reactions with Atmospheric Ozone

    Science.gov (United States)

    Hopkins, Frances; Bell, Thomas; Yang, Mingxi

    2017-04-01

    Ozone (O3) is a key atmospheric oxidant, greenhouse gas and air pollutant. In marine environments, some atmospheric ozone is lost by reactions with aqueous compounds (e.g. dissolved organic material, DOM, dimethyl sulfide, DMS, and iodide) near the sea surface. These reactions also lead to formations of volatile organic compounds (VOCs). Removal of O3 by the ocean remains a large uncertainty in global and regional chemical transport models, hampering coastal air quality forecasts. To better understand the role of the ocean in controlling O3 concentrations in the coastal marine atmosphere, we designed and implemented a series of laboratory experiments whereby ambient surface seawater was bubbled with O3-enriched, VOC-free air in a custom-made glass bubble equilibration system. Gas phase concentrations of a range of VOCs were monitored continuously over the mass range m/z 33 - 137 at the outflow of the bubble equilibrator by a proton transfer reaction - mass spectrometer (PTR-MS). Gas phase O3 was also measured at the input and output of the equilibrator to monitor the uptake due to reactions with dissolved compounds in seawater. We observed consistent productions of a variety of VOCs upon reaction with O3, notably isoprene, aldehydes, and ketones. Aqueous DMS is rapidly removed from the reactions with O3. To test the importance of dissolved organic matter precursors, we added increasing (milliliter) volumes of Emiliania huxleyi culture to the equilibrator filled with aged seawater, and observed significant linear increases in gas phase concentrations of a number of VOCs. Reactions between DOM and O3 at the sea-air interface represent a potentially significant source of VOCs in marine air and a sink of atmospheric O3.

  1. Study of organic sulphur compounds (DMS, DMSP and CS2) in lagoon ecosystems: the case of the Venice lagoon.

    Science.gov (United States)

    Gambaro, Andrea; Moret, Ivo; Piazza, Rossano; Andreoli, Carlo; Corami, Fabiana; Turetta, Clara; Cescon, Paolo

    2003-03-01

    This study of the origin and fate of dimethyl sulphide (DMS) in a particular and complex lagoon ecosystem such as that of the Venice lagoon focuses on the temporal evolutions of DMS concentrations in surface water together with those of dimethylsulphoniopropionate (DMSP), carbon disulphide (CS2), nutrients (nitrate, nitrite, ammonium, phosphate, silicate), sulphate, chlorophyll a, chlorinity, water temperature and phytoplankton (composition and density). Measurements were made from 3 March 1997 to 23 July 1998 at three stations in the central part of the Venice lagoon. The temporal trends of DMS concentration showed an absolute maximum concentration in winter (65 nmol S/l, 19/2/1998, Stn. 1; 119 nmol S/l, 19/2/1998, Stn. 2; 29 nmol S/l, 17/2/1998, Stn. 3) and two relative maxima in the spring-summer period. The spring-summer secondary maxima of DMS concentration were related to the maxima of DMSP and chlorophyll a concentrations and consequently to phytoplanktonic abundance while the winter DMS maximum showed no relation to DMSP or to chlorophyll a suggesting that the production and the fate of DMS could be different for the two periods. According to previous studies the CS2 concentration increased in the spring, achieved its maximum in summer, decreased in autumn and fell to its minimum in winter.

  2. Renal imaging with a new agent sup(99m)Tc-d1-DMS

    International Nuclear Information System (INIS)

    Tanaka, A.

    1980-01-01

    By using sup(99m)-Tc-d1 DMS labeled with 99 m-Tc using stannous chloride and prepared with freeze-dried d1-DMS containing a 3:1 molar ratio of DMS and Sn +2 the effect of stereochemical factor of DMS on kidney affinity, renal images, blood clearance, urinary excretion was studied in experimental animals and two normal volunteers and 75 patients. The comparation revealed a quite similar formation of complex II from d1-DMS to that from the meso-form, judge from its absorption spectra and absorption behavior into the gel. The stereochemical difference of DMS is not a critical factor for the formation of the sup(99m)-Tc-DMS complex with high affinity for the kidney, although it is believed that the renal accumulation of Tc-complex will depend greatly on chemical configuration of the complex. (APR)

  3. Biogenesis of the demarcation membrane system (DMS) in megakaryocytes

    NARCIS (Netherlands)

    Eckly, A.; Heijnen, H.F.G.; Pertuy, F.; Geerts, W.J.C.; Proamer, F.; Rinckel, J.Y.; Leon, C.; Lanza, F; Gachet, C.

    2014-01-01

    The demarcation membrane system (DMS) in megakaryocytes forms the plasma membrane (PM) of future platelets. Using confocal microscopy, electron tomography, and large volume focused ion beam/scanning electron microscopy (FIB/SEM), we determined the sequential steps of DMS formation. We identified a

  4. Grazing-Activated Production of Dimethyl Sulfide (DMS) by two clones of Emiliania huxleyi

    Science.gov (United States)

    Wolfe, Gordon V.; Steinke, Michael

    1996-01-01

    Emiliania huxleyi clones CCMP 370 and CCMP 373 produced similar amounts of dimethylsulfoniopropionate (DMSP) during axenic exponential growth, averaging 109 mM internal DMSP. Both clones had detectable DMSP lyase activity, as measured by production of dimethyl sulfide (DMS) during in vitro assays of crude cell preparations, but activities and conditions differed considerably between clones. Clone 373 had high activity; clone 370 had low activity and required chloride. For both strains, enzyme activity per cell was constant during exponential growth, but little DMS was produced by healthy cells. Rather, DMS production was activated when cells were subjected to physical or chemical stresses that caused cell lysis. We propose that DMSP lyase and DMSP are segregated within these cells and re-action only under conditions that result in cell stress or damage. Such activation occurs during microzooplankton grazing. When these clones were grazed by the dinoflagellate Oxyrrhis marina, DMS was produced; ungrazed cells, as well as those exposed to grazer exudates and associated bacteria, generated no DMS. Grazing of clone 373 produced much more DMS than grazing of clone 370, consistent with their relative in vitro DMSP lyase activities. DMS was only generated when cells were actually being grazed, indicating that ingested cells were responsible for the DMS formation. We suggest that even low levels of grazing can greatly accelerate DMS production.

  5. Determination of the photolysis rate coefficient of monochlorodimethyl sulfide (MClDMS) in the atmosphere and its implications for the enhancement of SO2 production from the DMS + Cl2 reaction.

    Science.gov (United States)

    Copeland, G; Lee, E P F; Williams, R G; Archibald, A T; Shallcross, D E; Dyke, J M

    2014-01-01

    In this work, the photolysis rate coefficient of CH3SCH2Cl (MClDMS) in the lower atmosphere has been determined and has been used in a marine boundary layer (MBL) box model to determine the enhancement of SO2 production arising from the reaction DMS + Cl2. Absorption cross sections measured in the 28000-34000 cm(-1) region have been used to determine photolysis rate coefficients of MClDMS in the troposphere at 10 solar zenith angles (SZAs). These have been used to determine the lifetimes of MClDMS in the troposphere. At 0° SZA, a photolysis lifetime of 3-4 h has been obtained. The results show that the photolysis lifetime of MClDMS is significantly smaller than the lifetimes with respect to reaction with OH (≈ 4.6 days) and with Cl atoms (≈ 1.2 days). It has also been shown, using experimentally derived dissociation energies with supporting quantum-chemical calculations, that the dominant photodissocation route of MClDMS is dissociation of the C-S bond to give CH3S and CH2Cl. MBL box modeling calculations show that buildup of MClDMS at night from the Cl2 + DMS reaction leads to enhanced SO2 production during the day. The extra SO2 arises from photolysis of MClDMS to give CH3S and CH2Cl, followed by subsequent oxidation of CH3S.

  6. The Obsolescence of DMS in an Information Centric World

    Science.gov (United States)

    2011-04-13

    system. DMS does this today already for submarines. It would only require a change in the programming of the existing Tactical Messaging Gateway ( TMG ...and NATO. The TMG , MFI and National Gateways convert the message into a format that can be read by the intended recipient. DMS is a fire and

  7. Isolation and Characterization of Surface and Subsurface Bacteria in Seawater of Mantanani Island, Kota Belud, Sabah by Direct and Enrichment Techniques

    International Nuclear Information System (INIS)

    Benard, L D; Tuah, P M; Suadin, E G; Jamian, N

    2015-01-01

    The distribution of hydrocarbon-utilizing bacterial may vary between surface and subsurface of the seawater. One of the identified contributors is the Total Petroleum Hydrocarbon. The isolation and characterization of bacteria using Direct and Enrichment techniques helps in identifying dominant bacterial populations in seawater of Mantanani Island, Kota Belud, Sabah, potential of further investigation as hydrocarbon degrader. Crude oil (5% v/v) was added as the carbon source for bacteria in Enrichment technique. For surface seawater, the highest population of bacteria identified for both Direct and Enrichment technique were 2.60 × 10 7 CFU/mL and 3.84 × 10 6 CFU/mL respectively. Meanwhile, for subsurface seawater, the highest population of bacteria identified for both Direct and Enrichment technique were 5.21 × 10 6 CFU/mL and 8.99 × 10 7 CFU/mL respectively. Dominant species in surface seawater were characterized as Marinobacter hydrocarbonoclasticus-RMSF-C1 and RMSF-C2 and Alcanivorax borkumensis-RMSF-C3, RMSF-C4 and RMSF-C5. As for subsurface seawater, dominant species were characterized as Pseudomonas luteola-SSBR-W1, Burkholderia cepacia-SSBR-C1, Rhizobium radiobacter- SSBR-C3 and Leuconostoc-cremois -SSBR-C4. (paper)

  8. WRAP Module 1 data management system (DMS) software design description (SDD)

    Energy Technology Data Exchange (ETDEWEB)

    Talmage, P.A.

    1995-03-17

    The Waste Receiving and Processing (WRAP) Module 1 Data Management System (DMS) System Design Description (SDD) describes the logical and physical architecture of the system. The WRAP 1 DMS SDD formally partitions the elements of the system described in the WRAP 1 DMS Software requirements specification into design objects and describes the key properties and relationships among the design objects and interfaces with external systems such as the WRAP Plant Control System (PCS). The WRAP 1 DMS SDD can be thought of as a detailed blueprint for implementation activities. The design descriptions contained within this document will describe, in detail, the software products that will be developed to assist the Project W-026, Waste Receiving and Processing Module 1, in their management functions. The WRAP 1 DMS is required to collect, store, and report data related to certification, tracking, packaging, repackaging, processing, and shipment of waste processed or stored at the WRAP 1 facility.

  9. WRAP Module 1 data management system (DMS) software design description (SDD)

    International Nuclear Information System (INIS)

    Talmage, P.A.

    1995-01-01

    The Waste Receiving and Processing (WRAP) Module 1 Data Management System (DMS) System Design Description (SDD) describes the logical and physical architecture of the system. The WRAP 1 DMS SDD formally partitions the elements of the system described in the WRAP 1 DMS Software requirements specification into design objects and describes the key properties and relationships among the design objects and interfaces with external systems such as the WRAP Plant Control System (PCS). The WRAP 1 DMS SDD can be thought of as a detailed blueprint for implementation activities. The design descriptions contained within this document will describe, in detail, the software products that will be developed to assist the Project W-026, Waste Receiving and Processing Module 1, in their management functions. The WRAP 1 DMS is required to collect, store, and report data related to certification, tracking, packaging, repackaging, processing, and shipment of waste processed or stored at the WRAP 1 facility

  10. DMS-MaPseq for genome-wide or targeted RNA structure probing in vivo.

    Science.gov (United States)

    Zubradt, Meghan; Gupta, Paromita; Persad, Sitara; Lambowitz, Alan M; Weissman, Jonathan S; Rouskin, Silvi

    2017-01-01

    Coupling of structure-specific in vivo chemical modification to next-generation sequencing is transforming RNA secondary structure studies in living cells. The dominant strategy for detecting in vivo chemical modifications uses reverse transcriptase truncation products, which introduce biases and necessitate population-average assessments of RNA structure. Here we present dimethyl sulfate (DMS) mutational profiling with sequencing (DMS-MaPseq), which encodes DMS modifications as mismatches using a thermostable group II intron reverse transcriptase. DMS-MaPseq yields a high signal-to-noise ratio, can report multiple structural features per molecule, and allows both genome-wide studies and focused in vivo investigations of even low-abundance RNAs. We apply DMS-MaPseq for the first analysis of RNA structure within an animal tissue and to identify a functional structure involved in noncanonical translation initiation. Additionally, we use DMS-MaPseq to compare the in vivo structure of pre-mRNAs with their mature isoforms. These applications illustrate DMS-MaPseq's capacity to dramatically expand in vivo analysis of RNA structure.

  11. Rate of mass deposition of scaling compounds from seawater on the outer surface of heat exchangers in MED evaporators

    Energy Technology Data Exchange (ETDEWEB)

    Omar, W. [Department of Natural Resources and Chemical Engineering, Tafila Technical University, Tafila (Jordan); Ulrich, J. [FB Ingenieurwissenschaften, Institut fuer Verfahrenstechnik/TVT, Martin-Luther-Universitaet Halle-Wittenberg, Halle (Germany)

    2006-08-15

    The scaling problem in Multi Effect Distillation (MED) evaporators is investigated by the experimental measurement of the deposition rate under different operating conditions. The measurements are conducted in a batch vessel containing artificial seawater, which is allowed to contact the outer surface of a hot pipe under controlled temperature, salinity and pH. The rate of mass deposition is higher at elevated temperature. The salinity of the seawater also influences the scaling process - an increase in salinity from 47-59 g/L leads to an increase of 75.6 % in the deposition rate. Decreasing the pH value of seawater to 2.01 results in a complete inhibition of scaling, whereas the severity of the scaling increases in neutral and basic mediums. Polyacrylic acid is tested as an antifoulant and it was found that its presence in seawater reduces the scaling process. The nature of the heat transfer surface material also plays an important role in the scaling process. It is found experimentally that the rate of scaling is higher in the case of a Cu-Ni alloy as the surface material of the tube rather than stainless steel. (Abstract Copyright [2006], Wiley Periodicals, Inc.)

  12. Wireless Sensor Node for Surface Seawater Density Measurements

    Directory of Open Access Journals (Sweden)

    Roberto Saletti

    2012-03-01

    Full Text Available An electronic meter to measure surface seawater density is presented. It is based on the measurement of the difference in displacements of a surface level probe and a weighted float, which according to Archimedes’ law depends on the density of the water. The displacements are simultaneously measured using a high-accuracy magnetostrictive sensor, to which a custom electronic board provides a wireless connection and power supply so that it can become part of a wireless sensor network. The electronics are designed so that different kinds of wireless networks can be used, by simply changing the wireless module and the relevant firmware of the microcontroller. Lastly, laboratory and at-sea tests are presented and discussed in order to highlight the functionality and the performance of a prototype of the wireless density meter node in a Bluetooth radio network. The experimental results show a good agreement of the values of the calculated density compared to reference hydrometer readings.

  13. Wireless sensor node for surface seawater density measurements.

    Science.gov (United States)

    Baronti, Federico; Fantechi, Gabriele; Roncella, Roberto; Saletti, Roberto

    2012-01-01

    An electronic meter to measure surface seawater density is presented. It is based on the measurement of the difference in displacements of a surface level probe and a weighted float, which according to Archimedes' law depends on the density of the water. The displacements are simultaneously measured using a high-accuracy magnetostrictive sensor, to which a custom electronic board provides a wireless connection and power supply so that it can become part of a wireless sensor network. The electronics are designed so that different kinds of wireless networks can be used, by simply changing the wireless module and the relevant firmware of the microcontroller. Lastly, laboratory and at-sea tests are presented and discussed in order to highlight the functionality and the performance of a prototype of the wireless density meter node in a Bluetooth radio network. The experimental results show a good agreement of the values of the calculated density compared to reference hydrometer readings.

  14. Chemical effect on ozone deposition over seawater

    Science.gov (United States)

    Surface layer resistance plays an important role in determining ozone deposition velocity over seawater. Recent studies suggest that surface layer resistance over sea-water is influenced by wind-speed and chemical interaction at the air-water interface. Here, we investigate the e...

  15. Long Range Transport was a Bigger NSS Source than DMS in the Remote Tropical MBL during PASE

    Science.gov (United States)

    Huebert, B. J.; Simpson, R. M.; Howell, S. G.; Blomquist, B.

    2013-12-01

    DMS was not the principal source of non-sea salt sulfate (NSS) mass in the remote marine boundary layer during the Pacific Atmospheric Sulfur Experiment (PASE), according to an Eulerian sulfur budget model based on chemical concentrations measured from the NCAR C-130 in the tropical Pacific. Each of our three (DMS, SO2, and NSS) self-consistent monthly- average budgets includes terms for surface exchange, entrainment, divergence, chemical formation, and chemical loss. The budget-derived DMS emission was (2.7 × 0.5 μmol m-2 d-1, our budget 'units'). SO2 sources include DMS + OH (1.4 × 0.4 units, assuming γ = 0.75) and entrainment from the free troposphere (FT) (0.8 × 0.2 units). Clouds were the most important chemical reactors for SO2 (-1.0 × 0.5 units). SO2 loss terms also include divergence (-0.9 × 0.3 units), dry deposition (-0.5 × 0.2 units), and OH + SO2 (-0.22 × 0.05 units). The total SO2 loss balanced the SO2 source. We found negligible NSS on particles from 2.6 μm to 10 μm diameter, the sea salt mass peak. Fine-particle NSS sources include in-cloud oxidation of SO2 by H2O2 (1.0 × 0.5 units), OH + SO2 (0.19 × 0.05 units), and entrainment (1.1 × 0.3 units in clean conditions; twice that when continental pollution is present). Only about 1/4 of emitted DMS becomes NSS. The NSS sources from entrainment and from DMS are similar in magnitude.

  16. 1D Compressibility of DMS Treated With Cement-GGBS Blend

    Directory of Open Access Journals (Sweden)

    Kaliannan Suaathi

    2017-01-01

    Full Text Available Great quantities of dredged marine soils (DMS have been produced from the maintenance of channels, anchorages and for harbour development. DMS have the potential to pose ecological and human health risks and it is also considered as a geowaste. Malaysia is moving towards the sustainability approach and one of the key factors to achieve it is to reduce waste. Thus, this geowaste should be generated as a new resource to substitute soil for civil works such as for land reclamation and backfilling. This shows the improved settlement of consolidation in treated DMS. DMS is referred to as a cohesive soil which includes clayey silt, sandy clay, silty clay and organic clay. This type of soil has low strength and high compressibility. The objectives were achieved through literature review analysis and also laboratory test which was one dimensional oedometer test. On the other hand, treated DMS with more ground granulated blast furnace slag (GGBS gives a lower settlement compared to specimen with higher percentage of cement in a treated soil. Thus this shows that cement content can be reduced in soil solidification when GGBS is added. The optimum binder ratio found was 3:7 where 3 is cement and 7 is GGBS.

  17. Technical Analysis of the Slosson-Diagnostic Math Screener (S-DMS)

    Science.gov (United States)

    Erford, Bradley T.; Klein, Lauren

    2007-01-01

    The Slosson-Diagnostic Math Screener (S-DMS) was designed to help identify students in Grades 1 to 8 at risk for mathematics failure. Internal consistency, test-retest reliability, item analysis, decision efficiency, convergent validity, and factorial validity of all five levels of the S-DMS were studied using 20 independent samples of students…

  18. SRB seawater corrosion project

    Science.gov (United States)

    Bozack, M. J.

    1991-01-01

    The corrosion behavior of 2219 aluminum when exposed to seawater was characterized. Controlled corrosion experiments at three different temperatures (30, 60 and 100 C) and two different environments (seawater and 3.5 percent salt solution) were designed to elucidate the initial stages in the corrosion process. It was found that 2219 aluminum is an active catalytic surface for growth of Al2O3, NaCl, and MgO. Formation of Al2O3 is favored at lower temperatures, while MgO is favored at higher temperatures. Visible corrosion products are formed within 30 minutes after seawater exposure. Corrosion characteristics in 3.5 percent salt solution are different than corrosion in seawater. Techniques utilized were: (1) scanning electron microscopy, (2) energy dispersive x-ray spectroscopy, and (3) Auger electron spectroscopy.

  19. Differential Mobility Spectrometry-Hydrogen Deuterium Exchange (DMS-HDX) as a Probe of Protein Conformation in Solution.

    Science.gov (United States)

    Zhu, Shaolong; Campbell, J Larry; Chernushevich, Igor; Le Blanc, J C Yves; Wilson, Derek J

    2016-06-01

    Differential mobility spectrometry (DMS) is an ion mobility technique that has been adopted chiefly as a pre-filter for small- to medium-sized analytes (DMS-field asymmetric waveform ion mobility spectroscopy (FAIMS)-the application of DMS to intact biomacromolecules remains largely unexplored. In this work, we employ DMS combined with gas-phase hydrogen deuterium exchange (DMS-HDX) to probe the gas-phase conformations generated from proteins that were initially folded, partially-folded, and unfolded in solution. Our findings indicate that proteins with distinct structural features in solution exhibit unique deuterium uptake profiles as function of their optimal transmission through the DMS. Ultimately we propose that DMS-HDX can, if properly implemented, provide rapid measurements of liquid-phase protein structural stability that could be of use in biopharmaceuticals development. Graphical Abstract ᅟ.

  20. DMS-Seq for In Vivo Genome-wide Mapping of Protein-DNA Interactions and Nucleosome Centers.

    Science.gov (United States)

    Umeyama, Taichi; Ito, Takashi

    2017-10-03

    Protein-DNA interactions provide the basis for chromatin structure and gene regulation. Comprehensive identification of protein-occupied sites is thus vital to an in-depth understanding of genome function. Dimethyl sulfate (DMS) is a chemical probe that has long been used to detect footprints of DNA-bound proteins in vitro and in vivo. Here, we describe a genomic footprinting method, dimethyl sulfate sequencing (DMS-seq), which exploits the cell-permeable nature of DMS to obviate the need for nuclear isolation. This feature makes DMS-seq simple in practice and removes the potential risk of protein re-localization during nuclear isolation. DMS-seq successfully detects transcription factors bound to cis-regulatory elements and non-canonical chromatin particles in nucleosome-free regions. Furthermore, an unexpected preference of DMS confers on DMS-seq a unique potential to directly detect nucleosome centers without using genetic manipulation. We expect that DMS-seq will serve as a characteristic method for genome-wide interrogation of in vivo protein-DNA interactions. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

  1. Model study of multiphase DMS oxidation with a focus on halogens

    Directory of Open Access Journals (Sweden)

    R. von Glasow

    2004-01-01

    Full Text Available We studied the oxidation of dimethylsulfide (DMS in the marine boundary layer (MBL with a one-dimensional numerical model and focused on the influence of halogens. Our model runs show that there is still significant uncertainty about the end products of the DMS addition pathway, which is especially caused by uncertainty in the product yield of the reaction of the intermediate product methyl sulfinic acid (MSIA with OH. BrO strongly increases the importance of the addition branch in the oxidation of DMS even when present at mixing ratios smaller than 0.5pmol mol-1. The inclusion of halogen chemistry leads to higher DMS oxidation rates and smaller DMS to SO2 conversion efficiencies. The DMS to SO2 conversion efficiency is also drastically reduced under cloudy conditions. In cloud-free model runs between 5 and 15% of the oxidized DMS reacts further to particulate sulfur, in cloudy runs this fraction is almost 100%. Sulfate production by HOClaq and HOBraq is important in cloud droplets even for small Br- deficits and related small gas phase halogen concentrations. In general, more particulate sulfur is formed when halogen chemistry is included. A possible enrichment of HCO3- in fresh sea salt aerosol would increase pH values enough to make the reaction of S(IV* (=SO2,aq+HSO3-+SO32- with O3 dominant for sulfate production. It leads to a shift from methyl sulfonic acid (MSA to non-sea salt sulfate (nss-SO42- production but increases the total nss-SO42- only somewhat because almost all available sulfur is already oxidized to particulate sulfur in the base scenario. We discuss how realistic this is for the MBL. We found the reaction MSAaq+OH to contribute about 10% to the production of nss-SO42- in clouds. It is unimportant for cloud-free model runs. Overall we find that the presence of halogens leads to processes that decrease the albedo of stratiform clouds in the MBL.

  2. Foundational Report Series: Advanced Distribution Management Systems for Grid Modernization, DMS Industry Survey

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Ravindra [Argonne National Lab. (ANL), Argonne, IL (United States); Uluski, Robert [Argonne National Lab. (ANL), Argonne, IL (United States); Reilly, James T. [Reilly Associates, Pittston, PA (United States); Martino, Sal [Electric Power Research Inst. (EPRI), Palo Alto, CA (United States); Lu, Xiaonan [Argonne National Lab. (ANL), Argonne, IL (United States); Wang, Jianhui [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-04-01

    The objective of this survey is to benchmark current practices for DMS implementation to serve as a guide for future system implementations. The survey sought information on current plans to implement DMS, DMS functions of interest, implementation challenges, functional benefits achieved, and other relevant information. These survey results were combined (where possible) with results of similar surveys conducted in the previous four years to observe trends over time.

  3. MMB4 DMS: cardiovascular and pulmonary effects on dogs and neurobehavioral effects on rats.

    Science.gov (United States)

    Roche, Brian M; Vinci, Tom M; Hawk, Michael A; Hassler, Craig R; Pressburger, David T; Osheroff, Merrill R; Ritchie, Glenn D; Burback, Brian L

    2013-01-01

    The objectives of these studies were to determine the cardiopulmonary effects of a single intramuscular administration of 1,1'-methylenebis[4-[(hydroxyimino)methyl]-pyridinium] dimethanesulfonate (MMB4 DMS) on dogs and on the central nervous system in rats. On days 1, 8, 15, and 22, male and female dogs received either vehicle (water for injection/0.5% benzyl alcohol/methane sulfonic acid) or MMB4 DMS (20, 50, or 100 mg/kg). Pulmonary function was evaluated for the first 5 hours after concurrent dosing with cardiovascular monitoring; then cardiovascular monitoring continued for 72 hours after dosing. Rats were dosed once by intramuscular injection with vehicle (water for injection/0.5% benzyl alcohol/methane sulfonic acid) or MMB4 DMS (60, 170, or 340 mg/kg). In dogs, 100 mg/kg MMB4 DMS resulted in increased blood pressure, slightly increased heart rate, slightly prolonged corrected QT, and moderately increased respiratory rate. There were no toxicological effects of MMB4 DMS on neurobehavioral function in rats administered up to 340 mg/kg MMB4 DMS.

  4. Space Station Freedom (SSF) Data Management System (DMS) performance model data base

    Science.gov (United States)

    Stovall, John R.

    1993-01-01

    The purpose of this document was originally to be a working document summarizing Space Station Freedom (SSF) Data Management System (DMS) hardware and software design, configuration, performance and estimated loading data from a myriad of source documents such that the parameters provided could be used to build a dynamic performance model of the DMS. The document is published at this time as a close-out of the DMS performance modeling effort resulting from the Clinton Administration mandated Space Station Redesign. The DMS as documented in this report is no longer a part of the redesigned Space Station. The performance modeling effort was a joint undertaking between the National Aeronautics and Space Administration (NASA) Johnson Space Center (JSC) Flight Data Systems Division (FDSD) and the NASA Ames Research Center (ARC) Spacecraft Data Systems Research Branch. The scope of this document is limited to the DMS core network through the Man Tended Configuration (MTC) as it existed prior to the 1993 Clinton Administration mandated Space Station Redesign. Data is provided for the Standard Data Processors (SDP's), Multiplexer/Demultiplexers (MDM's) and Mass Storage Units (MSU's). Planned future releases would have added the additional hardware and software descriptions needed to describe the complete DMS. Performance and loading data through the Permanent Manned Configuration (PMC) was to have been included as it became available. No future releases of this document are presently planned pending completion of the present Space Station Redesign activities and task reassessment.

  5. Coupling ANIMO and MT3DMS for 3D regional-scale modeling of nutrient transport in soil and groundwater

    Science.gov (United States)

    Janssen, G.; Del Val Alonso, L.; Groenendijk, P.; Griffioen, J.

    2012-12-01

    We developed an on-line coupling between the 1D/quasi-2D nutrient transport model ANIMO and the 3D groundwater transport model code MT3DMS. ANIMO is a detailed, process-oriented model code for the simulation of nitrate leaching to groundwater, N- and P-loads on surface waters and emissions of greenhouse gasses. It is the leading nutrient fate and transport code in the Netherlands where it is used primarily for the evaluation of fertilization related legislation. In addition, the code is applied frequently in international research projects. MT3DMS is probably the most commonly used groundwater solute transport package worldwide. The on-line model coupling ANIMO-MT3DMS combines the state-of-the-art descriptions of the biogeochemical cycles in ANIMO with the advantages of using a 3D approach for the transport through the saturated domain. These advantages include accounting for regional lateral transport, considering groundwater-surface water interactions more explicitly, and the possibility of using MODFLOW to obtain the flow fields. An additional merit of the on-line coupling concept is that it preserves feedbacks between the saturated and unsaturated zone. We tested ANIMO-MT3DMS by simulating nutrient transport for the period 1970-2007 in a Dutch agricultural polder catchment covering an area of 118 km2. The transient groundwater flow field had a temporal resolution of one day and was calculated with MODFLOW-MetaSWAP. The horizontal resolution of the model grid was 100x100m and consisted of 25 layers of varying thickness. To keep computation times manageable, we prepared MT3DMS for parallel computing, which in itself is a relevant development for a large community of groundwater transport modelers. For the parameterization of the soil, we applied a standard classification approach, representing the area by 60 units with unique combinations of soil type, land use and geohydrological setting. For the geochemical parameterization of the deeper subsurface, however, we

  6. Contribution of Seawater Surfactants to Generated Primary Marine Aerosol Particles

    Science.gov (United States)

    Frossard, A. A.; Gerard, V.; Duplessis, P.; Kinsey, J. D.; Lu, X.; Zhu, Y.; Bisgrove, J.; Maben, J. R.; Long, M. S.; Chang, R.; Beaupre, S. R.; Kieber, D. J.; Keene, W. C.; Noziere, B.; Cohen, R. C.

    2017-12-01

    Surfactants account for minor fractions of total organic carbon in the ocean but may have major impacts on the surface tension of bursting bubbles at the sea surface that drive the production of primary marine aerosol particles (PMA). Surfactants associated with marine aerosol may also significantly reduce the surface tension of water thereby increasing the potential for cloud droplet activation and growth. During September and October 2016, PMA were produced from bursting bubbles in seawater using a high capacity generator at two biologically productive and two oligotrophic stations in the western North Atlantic, as part of a cruise on the R/V Endeavor. Surfactants were extracted from paired PMA and seawater samples, and their ionic compositions, total concentrations, and critical micelle concentrations (CMC) were quantified and compared for the four hydrographic stations. Higher surfactant concentrations were determined in the aerosol produced from biologically productive seawater compared to oligotrophic seawater, and the surfactants extracted from productive seawater were stronger (had lower CMCs) than those in the oligotrophic seawater. Surfactants associated with PMA and seawater in productive regions also varied over diel cycles, whereas those in the oligotrophic regions did not. This work demonstrates a direct link between surfactants in seawater and those in PMA.

  7. IceBridge DMS L3 Photogrammetric DEM

    Data.gov (United States)

    National Aeronautics and Space Administration — The IceBridge DMS L3 Photogrammetric DEM (IODMS3) data set contains gridded digital elevation models and orthorectified images of Greenland derived from the Digital...

  8. WRAP module 1 DMS/PCS interface definition document

    International Nuclear Information System (INIS)

    Weidert, J.R.

    1994-01-01

    This document has been developed to define the computer software interfaces between Waste Receiving ampersand Processing Module 1 (WRAP 1) computer systems. The interfaces include those data interfaces which exist between the Plant Control System (PCS) and Data Management System (DMS), between the DMS and Non-Destructive Assay (NDA) equipment, and between the DMS and Boxed Waste Assay System (BWAS) equipment. In addition to the data interfaces between the various WRAP computer systems; there are also a number of control functions between WRAP 1 equipment. These control function interfaces have been specified in WRAP Construction specification 13462 and the associated equipment specifications. The PCS vendor has been listed in the equipment specifications as the responsible party for establishing the final control system interface between the PCS and Non-Destructive Examination (NDE) Equipment, the PCS and Non-Destructive Assay (NDA) Equipment, and the PCS and BWAS equipment. The primary interface requirements between these systems are addressed in Specification Sections 13462, 13532, 13533, 13026, 13537, and 13538. Additional requirements may be found in other specification sections such as the Automatic Stacker Retriever System (AS/RS) Technical Specification 14520 and the WRAP 1 Data Management System Software Requirements Specification

  9. Conjugate additions of a simple monosilylcopper reagent with use of the CuI.DMS complex: stereoselectivities and a dramatic impact by DMS.

    Science.gov (United States)

    Dambacher, Jesse; Bergdahl, Mikael

    2005-01-21

    Conjugate additions utilizing the simple monosilylcuprate reagent Li[PhMe2SiCuI] to alpha,beta-unsaturated carbonyl compounds are described. The presence of dimethyl sulfide (DMS), either as a component originating from the (CuI)4(DMS)3 complex or as a solvent added, has an amazing influence on both chemical yield and the level of diastereomeric ratio (dr) of the products. Gilman-type silylcyanocuprates {Li(Ph2MeSi)2Cu/LiCN} have previously been used to guarantee good results in conjugate addition reactions. External additives such as HMPA, tributylphosphine, or dialkylzinc are not necessary in conjunction with the simple Li[PhMe2SiCuI] reagent. It is demonstrated that the monosilylcuprate reagent with DMS as the solvent is very useful with sterically hindered (beta,beta-disubstituted) enones, and provides very high yields of the beta-silylated 1,4-addition products. Since there is no oligomerization problem associated with the simple monosilylcuprate reagent, this reagent should be considered as a very useful 1,4-silyl donor to enals, enones, and enoates in conjugate addition reactions.

  10. A study of the atmospherically important reactions of dimethylsulfide (DMS) with I2 and ICl using infrared matrix isolation spectroscopy and electronic structure calculations.

    Science.gov (United States)

    Beccaceci, Sonya; Armata, Nerina; Ogden, J Steven; Dyke, John M; Rhyman, Lydia; Ramasami, Ponnadurai

    2012-02-21

    The reactions of dimethylsulfide (DMS) with molecular iodine (I(2)) and iodine monochloride (ICl) have been studied by infrared matrix isolation spectroscopy by co-condensation of the reagents in an inert gas matrix. Molecular adducts of DMS + I(2) and DMS + ICl have also been prepared using standard synthetic methods. The vapour above each of these adducts trapped in an inert gas matrix gave the same infrared spectrum as that recorded for the corresponding co-condensation reaction. In each case, the infrared spectrum has been interpreted in terms of a van der Waals adduct, DMS : I(2) and DMS : ICl, with the aid of infrared spectra computed for their minimum energy structures at the MP2 level. Computed relative energies of minima and transition states on the potential energy surfaces of these reactions were used to understand why they do not proceed further than the reactant complexes DMS : I(2) and DMS : ICl. The main findings of this research are compared with results obtained earlier for the DMS + Cl(2) and DMS + Br(2) reactions, and the atmospheric implications of the conclusions are also considered.

  11. Do the organic sulfur compounds DMSP and DMS drive coral microbial associations?

    Science.gov (United States)

    Raina, Jean-Baptiste; Dinsdale, Elizabeth A; Willis, Bette L; Bourne, David G

    2010-03-01

    Dimethylsulfoniopropionate (DMSP) and dimethylsulfide (DMS) are key compounds in the global sulfur cycle. Moreover, DMS is particularly important in climate regulation owing to its role in cloud formation. Reef building corals are major contributors to the production of these two compounds and also form diverse and complex associations with bacteria, which are known to play a crucial role in the degradation of DMSP and DMS. Here, we highlight an extensive overlap between bacterial species implicated in DMSP/DMS degradation and those associated with corals, leading to the hypothesis that these two compounds play a major role in structuring coral-associated bacterial communities, with important consequences for coral health and the resilience of coral reefs. We also explore the publically available metagenome databases and show that genes implicated in DMSP metabolism are abundant in the viral component of coral-reef-derived metagenomes, indicating that viruses can act as a reservoir for such genes.

  12. Impacts of seawater rise on seawater intrusion in the Nile Delta Aquifer, Egypt.

    Science.gov (United States)

    Sefelnasr, Ahmed; Sherif, Mohsen

    2014-01-01

    Several investigations have recently considered the possible impacts of climate change and seawater level rise on seawater intrusion in coastal aquifers. All have revealed the severity of the problem and the significance of the landward movement of the dispersion zone under the condition of seawater level rise. Most of the studies did not consider the possible effects of the seawater rise on the inland movement of the shoreline and the associate changes in the boundary conditions at the seaside and the domain geometry. Such effects become more evident in flat, low land, coastal alluvial plans where large areas might be submerged with seawater under a relatively small increase in the seawater level. None of the studies combined the effect of increased groundwater pumping, due to the possible decline in precipitation and shortage in surface water resources, with the expected landward shift of the shore line. In this article, the possible effects of seawater level rise in the Mediterranean Sea on the seawater intrusion problem in the Nile Delta Aquifer are investigated using FEFLOW. The simulations are conducted in horizontal view while considering the effect of the shoreline landward shift using digital elevation models. In addition to the basic run (current conditions), six different scenarios are considered. Scenarios one, two, and three assume a 0.5 m seawater rise while the total pumping is reduced by 50%, maintained as per the current conditions and doubled, respectively. Scenarios four, five, and six assume a 1.0 m seawater rise and the total pumping is changed as in the first three scenarios. The shoreline is moved to account for the seawater rise and hence the study domain and the seaside boundary are modified accordingly. It is concluded that, large areas in the coastal zone of the Nile Delta will be submerged by seawater and the coast line will shift landward by several kilometers in the eastern and western sides of the Delta. Scenario six represents

  13. Therapeutic effects of sphingosine kinase inhibitor N,N-dimethylsphingosine (DMS) in experimental chronic Chagas disease cardiomyopathy.

    Science.gov (United States)

    Vasconcelos, Juliana Fraga; Meira, Cássio Santana; Silva, Daniela Nascimento; Nonaka, Carolina Kymie Vasques; Daltro, Pâmela Santana; Macambira, Simone Garcia; Domizi, Pablo Daniel; Borges, Valéria Matos; Ribeiro-Dos-Santos, Ricardo; de Freitas Souza, Bruno Solano; Soares, Milena Botelho Pereira

    2017-07-21

    Chagas disease cardiomyopathy is a parasite-driven inflammatory disease to which there are no effective treatments. Here we evaluated the therapeutic potential of N,N-dimethylsphingosine(DMS), which blocks the production of sphingosine-1-phosphate(S1P), a mediator of cellular events during inflammatory responses, in a model of chronic Chagas disease cardiomyopathy. DMS-treated, Trypanosoma cruzi-infected mice had a marked reduction of cardiac inflammation, fibrosis and galectin-3 expression when compared to controls. Serum concentrations of galectin-3, IFNγ and TNFα, as well as cardiac gene expression of inflammatory mediators were reduced after DMS treatment. The gene expression of M1 marker, iNOS, was decreased, while the M2 marker, arginase1, was increased. DMS-treated mice showed an improvement in exercise capacity. Moreover, DMS caused a reduction in parasite load in vivo. DMS inhibited the activation of lymphocytes, and reduced cytokines and NO production in activated macrophage cultures in vitro, while increasing IL-1β production. Analysis by qRT-PCR array showed that DMS treatment modulated inflammasome activation induced by T. cruzi on macrophages. Altogether, our results demonstrate that DMS, through anti-parasitic and immunomodulatory actions, can be beneficial in the treatment of chronic phase of T. cruzi infection and suggest that S1P-activated processes as possible therapeutic targets for the treatment of Chagas disease cardiomyopathy.

  14. Boundary layer and free-tropospheric dimethyl sulfide in the Arctic spring and summer

    Science.gov (United States)

    Ghahremaninezhad, Roghayeh; Norman, Ann-Lise; Croft, Betty; Martin, Randall V.; Pierce, Jeffrey R.; Burkart, Julia; Rempillo, Ofelia; Bozem, Heiko; Kunkel, Daniel; Thomas, Jennie L.; Aliabadi, Amir A.; Wentworth, Gregory R.; Levasseur, Maurice; Staebler, Ralf M.; Sharma, Sangeeta; Leaitch, W. Richard

    2017-07-01

    Vertical distributions of atmospheric dimethyl sulfide (DMS(g)) were sampled aboard the research aircraft Polar 6 near Lancaster Sound, Nunavut, Canada, in July 2014 and on pan-Arctic flights in April 2015 that started from Longyearbyen, Spitzbergen, and passed through Alert and Eureka, Nunavut, and Inuvik, Northwest Territories. Larger mean DMS(g) mixing ratios were present during April 2015 (campaign mean of 116 ± 8 pptv) compared to July 2014 (campaign mean of 20 ± 6 pptv). During July 2014, the largest mixing ratios were found near the surface over the ice edge and open water. DMS(g) mixing ratios decreased with altitude up to about 3 km. During April 2015, profiles of DMS(g) were more uniform with height and some profiles showed an increase with altitude. DMS reached as high as 100 pptv near 2500 m. Relative to the observation averages, GEOS-Chem (www.geos-chem.org) chemical transport model simulations were higher during July and lower during April. Based on the simulations, more than 90 % of the July DMS(g) below 2 km and more than 90 % of the April DMS(g) originated from Arctic seawater (north of 66° N). During April, 60 % of the DMS(g), between 500 and 3000 m originated from Arctic seawater. During July 2014, FLEXPART (FLEXible PARTicle dispersion model) simulations locate the sampled air mass over Baffin Bay and the Canadian Arctic Archipelago 4 days back from the observations. During April 2015, the locations of the air masses 4 days back from sampling were varied: Baffin Bay/Canadian Archipelago, the Arctic Ocean, Greenland and the Pacific Ocean. Our results highlight the role of open water below the flight as the source of DMS(g) during July 2014 and the influence of long-range transport (LRT) of DMS(g) from further afield in the Arctic above 2500 m during April 2015.

  15. Spatial variations of DMS, DMSP and phytoplankton in the Bay of Bengal during the summer monsoon 2001.

    Science.gov (United States)

    Shenoy, D M; Paul, Jane T; Gauns, Mangesh; Ramaiah, N; Kumar, M Dileep

    2006-08-01

    Data on the distribution of dimethylsulphide (DMS) and dimethylsulphoniopropionate (DMSP) in relation to phytoplankton abundance in different oceanic environments is important to understand the biogeochemistry of DMS, which plays an important role in the radiation balance of the earth. During the summer monsoon of 2001 measurements were made for DMS and DMSPt (total DMSP) together with related biological parameters in the Bay of Bengal. Both DMS and DMSPt were restricted to the upper 40 m of the water column. Diatoms accounted for more than 95% of the phytoplankton and were the major contributors to the DMS and DMSPt pool. The mean concentration of DMS in the upper 40 m was observed to be around 1.8+/-1.9 nM in the study area, while DMSPt concentrations varied between 0.7 nM and 40.2 nM with a mean of 10.4+/-8.2 nM. The observed lower DMSPt in the northern Bay in spite of higher mean primary productivity, chlorophyll a and phytoplankton cell counts seemed to result from grazing. Though salinity divides the Bay into different biogeochemical provinces there is no relation between salinity and DMS or DMSPt. On the other hand DMS was linearly related to chlorophyll a:phaeopigments ratio. The results suggest the need for deeper insight into the role of diatoms in the biogeochemical cycling of DMS.

  16. DMS cyclone separation processes for optimization of plastic wastes recycling and their implications.

    Science.gov (United States)

    Gent, Malcolm Richard; Menendez, Mario; Toraño, Javier; Torno, Susana

    2011-06-01

    It is demonstrated that substantial reductions in plastics presently disposed of in landfills can be achieved by cyclone density media separation (DMS). In comparison with the size fraction of plastics presently processed by industrial density separations (generally 6.4 to 9.5 mm), cyclone DMS methods are demonstrated to effectively process a substantially greater range of particle sizes (from 0.5 up to 120 mm). The purities of plastic products and recoveries obtained with a single stage separation using a cylindrical cyclone are shown to attain virtually 100% purity and recoveries >99% for high-density fractions and >98% purity and recoveries were obtained for low-density products. Four alternative schemas of multi-stage separations are presented and analyzed as proposed methods to obtain total low- and high-density plastics fraction recoveries while maintaining near 100% purities. The results of preliminary tests of two of these show that the potential for processing product purities and recoveries >99.98% of both density fractions are indicated. A preliminary economic comparison of capital costs of DMS systems suggests cyclone DMS methods to be comparable with other DMS processes even if the high volume capacity for recycling operations of these is not optimized.

  17. Foundational Report Series: Advanced Distribution Management Systems for Grid Modernization, High-Level Use Cases for DMS

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jianhui [Argonne National Lab. (ANL), Argonne, IL (United States); Lu, Xiaonan [Argonne National Lab. (ANL), Argonne, IL (United States); Martino, Sal [Reilly Associates, East Stroudsburg, PA (United States); Reilly, James T. [Electric Power Research Inst. (EPRI), Knoxville, TN (United States)

    2016-02-01

    Many distribution management systems (DMS) projects have achieved limited success because the electric utility did not sufficiently plan for actual use of the DMS functions in the control room environment. As a result, end users were not clear on how to use the new application software in actual production environments with existing, well-established business processes. An important first step in the DMS implementation process is development and refinement of the “to be” business processes. Development of use cases for the required DMS application functions is a key activity that leads to the formulation of the “to be” requirements. It is also an important activity that is needed to develop specifications that are used to procure a new DMS.

  18. DMS Advanced Applications for Accommodating High Penetrations of DERs and Microgrids: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Pratt, Annabelle [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Veda, Santosh [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Maitra, Arindam [Electric Power Research Institute; Hubert, Tanguy [Electric Power Research Institute; Reilly, Jim [Reilly Associates; Wang, JIanhui [Argonne National Laboratory; Singh, Ravindra [Argonne National Laboratory; Kang, Ning [Argonne National Laboratory; Lu, Xiaonan [Argonne National Laboratory

    2017-08-24

    Efficient and effective management of the electrical distribution system requires an integrated system approach for Distribution Management Systems (DMS), Distributed Energy Resources (DERs), Distributed Energy Resources Management System (DERMS), and microgrids to work in harmony. This paper highlights some of the outcomes from a U.S. Department of Energy (DOE), Office of Electricity (OE) project, including 1) Architecture of these integrated systems, and 2) Expanded functions of two example DMS applications, Volt-VAR optimization (VVO) and Fault Location, Isolation and Service Restoration (FLISR), to accommodate DER. For these two example applications, the relevant DER Group Functions necessary to support communication between DMS and Microgrid Controller (MC) in grid-tied mode are identified.

  19. Tc(V)-DMS tumour imaging agent

    International Nuclear Information System (INIS)

    Horiuchi, K.; Yomoda, I.; Yokoyama, A.; Endo, K.; Torizuka, K.

    1986-01-01

    The data obtained by the authors provide good evidence of Tc(V)-DMS as a stable, large-molecular-size Tc-complex or polynuclear Tc-complex, comparable to Tc-cit and Ga-cit. A role for this polynuclear configuration in the generation of Tc-species with affinity for neoplastic cells was demonstrated using the dilution method as a promoter of Tc(V)-DMS dissociation. The concurrent Ehrlich ascites tumour cell uptake studies with TLC analysis revealed the chromatographically detected changes well traced by the biological cell utilization. The biological implications of dilution as one of the factors regulating radiopharmaceutical delivery to the tumour cell tissue were better demonstrated in the biodistribution studies carried out with Erhlich ascites-bearing mice. If, on the basis of the present data, the authors may take their postulate one step further, a more dissociated Tc-species, defined speculatively as TcO/sub 4//sup 3-/, might constitute an active Tc- species within the cell interacting with some tumour-specific substance or site. Research to find evidence of its presence is currently in progress

  20. Development and evoluation of a DMS-based method for the detection of insecticides.

    Science.gov (United States)

    Differential mobility spectrometry (DMS), also referred to as high-field asymmetric waveform ion mobility spectromety (FAIMS), is a reapidly advancing technology for gas-phase separation. DMS has the potential to emerge as a major stand-alone separation technique such as LC or GC. To date, several...

  1. Development and Evaluation of a DMS-based Method for the Detection of Insecticides

    Science.gov (United States)

    Differential mobility spectrometry (DMS), also commonly referred to as high-field asymmetric waveform ion mobility spectrometry (FAIMS), is a rapidly advancing technology for gas-phase separation. DMS has the potential to emerge as a major stand-alone separation technique such as LC or GC. To date,...

  2. Role of bacteria in DMS(P) cycle

    Digital Repository Service at National Institute of Oceanography (India)

    Kumar, S.S.; Chinchkar, U.; Nair, S.; LokaBharathi, P.A.; Chandramohan, D.

    - lower atmosphere study Role of bacteria in DMS(P) cycle Sree S. Kumar, Usha Chinchkar, Shanta Nair, P. A. Loka Bharathi and D. Chandramohan - contact: ksree@nio.org National Institute of Oceanography, Dona Paula. Goa. India. 403 004 Sree Kumar is a...

  3. Temporal variations of 137Cs concentrations in the surface seawater and marine organisms collected from the Japanese coast during the 1980's

    International Nuclear Information System (INIS)

    Yamada, M.; Nagaya, Y.

    1998-01-01

    The surface seawater and marine organisms were collected on the Japanese coast and analyzed for their 137 Cs concentrations during the 1980's. The 137 Cs concentrations in surface seawater decreased almost exponentially with time and the 137 Cs removal rate constant was estimated to be 0.0445 y -1 . The 137 Cs concentrations in marine organisms also decreased almost exponentially with time. The environmental half-lives of 137 Cs in muscle and viscera of fish, crustacea, and seaweed were estimated from the measured decreases of 137 Cs concentrations. (author)

  4. Modeling variably saturated subsurface solute transport with MODFLOW-UZF and MT3DMS

    Science.gov (United States)

    Morway, Eric D.; Niswonger, Richard G.; Langevin, Christian D.; Bailey, Ryan T.; Healy, Richard W.

    2013-01-01

    The MT3DMS groundwater solute transport model was modified to simulate solute transport in the unsaturated zone by incorporating the unsaturated-zone flow (UZF1) package developed for MODFLOW. The modified MT3DMS code uses a volume-averaged approach in which Lagrangian-based UZF1 fluid fluxes and storage changes are mapped onto a fixed grid. Referred to as UZF-MT3DMS, the linked model was tested against published benchmarks solved analytically as well as against other published codes, most frequently the U.S. Geological Survey's Variably-Saturated Two-Dimensional Flow and Transport Model. Results from a suite of test cases demonstrate that the modified code accurately simulates solute advection, dispersion, and reaction in the unsaturated zone. Two- and three-dimensional simulations also were investigated to ensure unsaturated-saturated zone interaction was simulated correctly. Because the UZF1 solution is analytical, large-scale flow and transport investigations can be performed free from the computational and data burdens required by numerical solutions to Richards' equation. Results demonstrate that significant simulation runtime savings can be achieved with UZF-MT3DMS, an important development when hundreds or thousands of model runs are required during parameter estimation and uncertainty analysis. Three-dimensional variably saturated flow and transport simulations revealed UZF-MT3DMS to have runtimes that are less than one tenth of the time required by models that rely on Richards' equation. Given its accuracy and efficiency, and the wide-spread use of both MODFLOW and MT3DMS, the added capability of unsaturated-zone transport in this familiar modeling framework stands to benefit a broad user-ship.

  5. Treatment of waste gas containing low concentration of dimethyl sulphide (DMS) in a bench-scale biofilter.

    Science.gov (United States)

    Giri, B S; Mudliar, S N; Deshmukh, S C; Banerjee, S; Pandey, R A

    2010-04-01

    Biological treatment of dimethyl sulphide (DMS) was investigated in a bench-scale biofilter, packed with compost along with wood chips, and enriched with DMS degrading microorganism Bacillus sphaericus. The biofilter could remove 62-74% of the inlet DMS, at an optimum loading of 0.484 g/m(3)/h with optimum empty bed contact time (EBCT) of 384 s and an average moisture range of 65-70%. The biodegradative products of DMS were sulphide, thiosulphate and sulphate. Evaluation of microbiological status of the biofilter indicated the presence of other bacterial cultures viz. Paenibacillus polymyxa, and Bacillus megaterium, besides B. sphaericus. Copyright 2009 Elsevier Ltd. All rights reserved.

  6. Antitumor activity of [Pt(O,O'-acac)(γ-acac)(DMS)] in mouse xenograft model of breast cancer.

    Science.gov (United States)

    Muscella, A; Vetrugno, C; Migoni, D; Biagioni, F; Fanizzi, F P; Fornai, F; De Pascali, S A; Marsigliante, S

    2014-01-23

    The higher and selective cytotoxicity of [Pt(O,O'-acac)(γ-acac)(DMS)] toward cancer cell in both immortalized cell lines and in breast cancer cells in primary cultures, stimulated a pre-clinical study so as to evaluate its therapeutic potential in vivo. The efficacy of [Pt(O,O'-acac)(γ-acac)(DMS)] was assessed using a xenograft model of breast cancer developed by injection of MCF-7 cells in the flank of BALB/c nude mice. Treatment of solid tumor-bearing mice with [Pt(O,O'-acac)(γ-acac)(DMS)] induced up to 50% reduction of tumor mass compared with an average 10% inhibition recorded in cisplatin-treated animals. Thus, chemotherapy with [Pt(O,O'-acac)(γ-acac)(DMS)] was much more effective than cisplatin. We also demonstrated enhanced in vivo pharmacokinetics, biodistribution and tolerability of [Pt(O,O'-acac)(γ-acac)(DMS)] when compared with cisplatin administered in Wistar rats. Pharmacokinetics studies with [Pt(O,O'-acac)(γ-acac)(DMS)] revealed prolonged Pt persistence in systemic blood circulation and decreased nefrotoxicity and hepatotoxicity, major target sites of cisplatin toxicity. Overall, [Pt(O,O'-acac)(γ-acac)(DMS)] turned out to be extremely promising in terms of greater in vivo anticancer activity, reduced nephrotoxicity and acute toxicity compared with cisplatin.

  7. Structure of the bacterial community in a biofilter during dimethyl sulfide (DMS) removal processes.

    Science.gov (United States)

    Chung, Ying-Chien; Cheng, Chiu-Yu; Chen, Tzu-Yu; Hsu, Jo-Shan; Kui, Chun-Chi

    2010-09-01

    We report here both the successful treatment of DMS in a biofilter and the dynamic changes that occur in the composition of the bacterial community of the biofilter during this process. Denaturing gradient gel electrophoresis of eubacterial 16S rDNA samples taken from packing material at different DMS removal stages revealed 11 distinct bands. Phylogenetic analysis showed that the sequences of these bands were closest to sequences of species of the Proteobacteria, Firmicutes, and Actinobacteria. The specific occurrence of these bacterial species varied mainly with DMS load, but it was also affected by the addition of glucose and by ambient temperature. Based on the characteristics of the identified species, the system is conducive for such processes as sulfur oxidation, sulfate reduction, carbon oxidation, and fermentation. The strains identified in this study are potential candidates for purifying waste gas effluents containing DMS gas. Copyright 2010 Elsevier Ltd. All rights reserved.

  8. Detection of Radiation-Exposure Biomarkers by Differential Mobility Prefiltered Mass Spectrometry (DMS-MS).

    Science.gov (United States)

    Coy, Stephen L; Krylov, Evgeny V; Schneider, Bradley B; Covey, Thomas R; Brenner, David J; Tyburski, John B; Patterson, Andrew D; Krausz, Kris W; Fornace, Albert J; Nazarov, Erkinjon G

    2010-04-15

    Technology to enable rapid screening for radiation exposure has been identified as an important need, and, as a part of a NIH / NIAD effort in this direction, metabolomic biomarkers for radiation exposure have been identified in a recent series of papers. To reduce the time necessary to detect and measure these biomarkers, differential mobility spectrometry - mass spectrometry (DMS-MS) systems have been developed and tested. Differential mobility ion filters preselect specific ions and also suppress chemical noise created in typical atmospheric-pressure ionization sources (ESI, MALDI, and others). Differential-mobility-based ion selection is based on the field dependence of ion mobility, which, in turn, depends on ion characteristics that include conformation, charge distribution, molecular polarizability, and other properties, and on the transport gas composition which can be modified to enhance resolution. DMS-MS is able to resolve small-molecule biomarkers from nearly-isobaric interferences, and suppresses chemical noise generated in the ion source and in the mass spectrometer, improving selectivity and quantitative accuracy. Our planar DMS design is rapid, operating in a few milliseconds, and analyzes ions before fragmentation. Depending on MS inlet conditions, DMS-selected ions can be dissociated in the MS inlet expansion, before mass analysis, providing a capability similar to MS/MS with simpler instrumentation. This report presents selected DMS-MS experimental results, including resolution of complex test mixtures of isobaric compounds, separation of charge states, separation of isobaric biomarkers (citrate and isocitrate), and separation of nearly-isobaric biomarker anions in direct analysis of a bio-fluid sample from the radiation-treated group of a mouse-model study. These uses of DMS combined with moderate resolution MS instrumentation indicate the feasibility of field-deployable instrumentation for biomarker evaluation.

  9. Chlorine-36 in seawater

    International Nuclear Information System (INIS)

    Argento, David C.; Stone, John O.; Keith Fifield, L.; Tims, Stephen G.

    2010-01-01

    Natural cosmogenic 36 Cl found in seawater originates from spallation of atmospheric 40 Ar, capture of secondary cosmic-ray neutrons by dissolved 35 Cl, and river runoff which contains 36 Cl produced in situ over the surface of the continents. The long residence time of chloride in the ocean and long half-life of 36 Cl compared to the oceanic mixing time should result in a homogenous 36 Cl/Cl ratio throughout the ocean. Production by neutron capture in the course of nuclear weapons testing should be insignificant averaged over the oceans as a whole, but may have led to regions of elevated 36 Cl concentration. Previous attempts to measure the 36 Cl/Cl ratio of seawater have been hindered by interferences, contamination, or insufficient analytic sensitivity. Here we report preliminary measurements on seawater samples, which demonstrate that the 36 Cl/Cl ratio is 0.5 ± 0.3 x 10 -15 , in reasonable agreement with calculated contributions from the sources listed above.

  10. The signalling axis mediating neuronal apoptosis in response to [Pt(O,O'-acac)(γ-acac)(DMS)].

    Science.gov (United States)

    Muscella, Antonella; Calabriso, Nadia; Vetrugno, Carla; Fanizzi, Francesco Paolo; De Pascali, Sandra Angelica; Marsigliante, Santo

    2011-06-01

    It was previously shown that [Pt(O,O'-acac)(γ-acac)(DMS)] induces apoptosis in various cancer cells and exerts antimetastatic responses in vitro. In rats, [Pt(O,O'-acac)(γ-acac)(DMS)] reaches the central nervous system in quantities higher than cisplatin causing less excitotoxicity. The aim of the present paper was to investigate whether [Pt(O,O'-acac)(γ-acac)(DMS)] is able to exert cytotoxic effects on SH-SY5Y human neuroblastoma cell line, and to study the intracellular transduction mechanisms underlying these effects. Here we have demonstrated that [Pt(O,O'-acac)(γ-acac)(DMS)] was more effective than cisplatin in provoking apoptosis characterized by: (a) mitochondria depolarization, (b) decrease of Bcl-2 expression and increase of BAX expressions with cytosol-to-mitochondria translocation, (c) activation of caspase-7 and -9 and (d) generation of reactive oxygen species (ROS). [Pt(O,O'-acac)(γ-acac)(DMS)] provoked the activation of the following signalling kinases that were interacting with each other: PKC-δ and -ɛ, ERK1/2, p38MAPK, JNK1/2, NF-κB, c-src and FAK. We found that ROS generated by NADPH oxidase was responsible for the [Pt(O,O'-acac)(γ-acac)(DMS)]-mediated PKC-δ and -ɛ activation and consequential phosphorylation of all MAPKs. [Pt(O,O'-acac)(γ-acac)(DMS)]-induced mitochondrial apoptosis was blocked when p38MAPK and JNK1/2 were inhibited, whilst the effects on Bax/Bcl-2 mRNA and protein levels were blocked inhibiting NF-κB. NF-κB nuclear translocation was blocked inhibiting MEK1/2 activity. In addition to the induction of apoptosis [Pt(O,O'-acac)(γ-acac)(DMS)] downregulated pro-survival pathway. Survival inhibition started from mitochondrial ROS generation which induced c-src, FAK and Akt activation. In conclusion, our results suggest that [Pt(O,O'-acac)(γ-acac)(DMS)] may be considered a promising compound for the treatment of neuroblastoma. Further studies are warranted to explore in detail the therapeutic potential of this compound

  11. Marinobacterium sp. strain DMS-S1 uses dimethyl sulphide as a sulphur source after light-dependent transformation by excreted flavins.

    Science.gov (United States)

    Hirano, Hiroyuki; Yoshida, Takako; Fuse, Hiroyuki; Endo, Takayuki; Habe, Hiroshi; Nojiri, Hideaki; Omori, Toshio

    2003-06-01

    Marinobacterium sp. strain DMS-S1 is a unique marine bacterium that can use dimethyl sulphide (DMS) as a sulphur source only in the presence of light. High-performance liquid chromatography (HPLC) analyses of the culture supernatant revealed that excreted factors, which could transform DMS to dimethyl sulphoxide (DMSO) under light, are FAD and riboflavin. In addition, FAD appeared to catalyse the photolysis of DMS to not only DMSO but also methanesulphonate (MSA), formate, formaldehyde and sulphate. As strain DMS-S1 can use sulphate and MSA as a sole sulphur source independently of light, the excretion of flavins appeared to support the growth on DMS under light. Furthermore, three out of 12 marine bacteria from IAM culture collection were found to be able to grow on DMS with the aid of photolysis by the flavins excreted. This is the first report that bacteria can use light to assimilate oceanic organic sulphur compounds outside the cells by excreting flavins as photosensitizers.

  12. Distribution of trace metals in surface seawater and zooplankton of the Bay of Bengal, off Rushikulya estuary, East Coast of India.

    Science.gov (United States)

    Srichandan, Suchismita; Panigrahy, R C; Baliarsingh, S K; Rao B, Srinivasa; Pati, Premalata; Sahu, Biraja K; Sahu, K C

    2016-10-15

    Concentrations of trace metals such as iron (Fe), copper (Cu), zinc (Zn), cobalt (Co), nickel (Ni), manganese (Mn), lead (Pb), cadmium (Cd), chromium (Cr), arsenic (As), vanadium (V), and selenium (Se) were determined in seawater and zooplankton from the surface waters off Rushikulya estuary, north-western Bay of Bengal. During the study period, the concentration of trace metals in seawater and zooplankton showed significant spatio-temporal variation. Cu and Co levels in seawater mostly remained non-detectable. Other elements were found at higher concentrations and exhibited marked variations. The rank order distribution of trace metals in terms of their average concentration in seawater was observed as Fe>Ni>Mn>Pb>As>Zn>Cr>V>Se>Cd while in zooplankton it was Fe>Mn>Cd>As>Pb>Ni>Cr>Zn>V>Se. The bioaccumulation factor (BAF) of Fe was highest followed by Zn and the lowest value was observed with Ni. Results of correlation analysis discerned positive affinity and good relationship among the majority of the trace metals, both in seawater and zooplankton suggesting their strong affinity and coexistence. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Determination of trace metals in coastal seawater around Okinawa and its multielement profiling analysis

    International Nuclear Information System (INIS)

    Itoh, Akihide; Ishigaki, Teruyuki; Arakaki, Teruo; Yamada, Ayako; Yamaguchi, Mami; Kabe, Noriko

    2009-01-01

    In the present study, trace metals in coastal surface seawater around Okinawa were determined by inductively coupled plasma mass spectrometry (ICP-MS) with chelating disk preconcentration. As a result, the concentrations of V, Mn, Co, Ni, Cu, Zn, Mo, Cd, Pb, and U were obtained in the range from 10 μgL -1 to 0.001 μgL -1 for 6 samples. In addition, multielement profiling analyses were carried out using analytical values obtained in order to elucidate the features of trace metals in each coastal sea area. For coastal surface seawater near an urban area, the analytical values for Zn, Cu, Mn, and Pb were higher by more than 10-fold the literature values for open-surface seawater, and those of Cd were also relatively high. Such a trend concerning the multi-element profile was almost similar to the literature values for coastal seawater of the main island of Japan. On the other hand, the analytical values of most elements for coastal surface seawater near a suburb area were in the range from 0.5 to 5 fold, compared to the literature values for open surface seawater. From multielement profiling analyses for nutrient type elements in marine chemistry, it was suggested that the concentrations of Zn and Cd in a coral sea area normalized to literature values for open surface-seawater were higher than those of Ni and Cu. (author)

  14. DMS test summary report for the WRAP facility

    Energy Technology Data Exchange (ETDEWEB)

    Weidert, J.R.

    1997-11-04

    This report documents the functional and integration testing process performed to verify functionality of the Release 1.1, Release 2.0, Release 3.0 and Release 3.1 software for the Waste Receiving and Processing Facility (WRAP) Data Management Systems (DMS) Release 2.

  15. DMS test summary report for the WRAP facility

    International Nuclear Information System (INIS)

    Weidert, J.R.

    1997-01-01

    This report documents the functional and integration testing process performed to verify functionality of the Release 1.1, Release 2.0, Release 3.0 and Release 3.1 software for the Waste Receiving and Processing Facility (WRAP) Data Management Systems (DMS) Release 2

  16. Spatial variations in microbial community composition in surface seawater from the ultra-oligotrophic center to rim of the South Pacific Gyre.

    Directory of Open Access Journals (Sweden)

    Qi Yin

    Full Text Available Surface seawater in the South Pacific Gyre (SPG is one of the cleanest oceanic environments on earth, and the photosynthetic primary production is extremely low. Despite the ecological significance of the largest aquatic desert on our planet, microbial community composition in the ultra-oligotrophic seawater remain largely unknown. In this study, we collected surface seawater along a southern transect of the SPG during the Integrated Ocean Drilling Program (IODP Expedition 329. Samples from four distinct sites (Sites U1368, U1369, U1370 and U1371 were examined, representing ~5400 kilometers of transect line from the gyre heart to the edge area. Real-time PCR analysis showed 16S rRNA gene abundance in the gyre seawater, ranging from 5.96×10(5 to 2.55×10(6 copies ml(-1 for Bacteria and 1.17×10(3 to 1.90×10(4 copies ml(-1 for Archaea. The results obtained by statistic analyses of 16S rRNA gene clone libraries revealed the community composition in the southern SPG area: diversity richness estimators in the gyre center (Sites U1368 & U1369 are generally lower than those at sites in the gyre edge (Sites U1370 & U1371 and their community structures are clearly distinguishable. Phylogenetic analysis showed the predominance of Proteobacteria (especially Alphaproteobacteria and Cyanobacteria in bacterial 16S rRNA gene clone libraries, whereas phylotypes of Betaproteobacteria were only detected in the central gyre. Archaeal 16S rRNA genes in the clone libraries were predominated by the sequences of Marine Group II within the Euryarchaeota, and the Crenarchaeota sequences were rarely detected, which is consistent with the real-time PCR data (only 9.9 to 22.1 copies ml(-1. We also performed cultivation of heterotrophic microbes onboard, resulting in 18.9% of phylogenetically distinct bacterial isolates at least at the species level. Our results suggest that the distribution and diversity of microbial communities in the SPG surface seawater are closely

  17. Skeletal affinity of Tc(V)-DMS is bone cell mediated and pH dependent.

    Science.gov (United States)

    Horiuchi-Suzuki, Kazuko; Konno, Aya; Ueda, Mayumi; Fukuda, Yoko; Nishio, Saori; Hashimoto, Kazuyuki; Saji, Hideo

    2004-03-01

    In spite of recent advances in bone cellular and molecular biology, there is still a poor correlation between these parameters and data obtained from bone scintigraphy. Diphosphonate derivatives radiolabelled with technetium-99m (Tc-BPs) have long been recognised as bone-seeking agents with an affinity for areas of active mineralisation. However, during clinical trials with a pH-sensitive tumour agent, the pentavalent technetium complex of dimercaptosuccinic acid [Tc(V)-DMS] showed a noticeable osteotropic character only in bone pathologies (bone metastases, Paget's diseases) and lacked accumulation in normal mature bone. To decipher the osteotropic character of Tc(V)-DMS, a study at the cellular level was considered necessary. Moreover, to learn more about the role of Tc bone agents, acid-base regulation by bone tissue or cells was studied. First, biological parameters in body fluid were measured under systemic acidosis, induced by glucose administration, in normal and Ehrlich ascites tumour (EAT)-bearing mice. Then, in vivo biodistribution studies using Tc(V)-DMS or a conventional Tc-BP agent were carried out. The effect of glucose-mediated acidification on the skeletal distribution of the Tc agents in the mice provided valuable hints regarding the differential mediation of bone cells in skeletal tissue affinity for the agents. Thereafter, in vitro studies on osteoblast and osteoclast cells were performed and the comparative affinity of Tc(V)-DMS and Tc-BP was screened under diverse acidification conditions. Moreover, studies were also carried out on acid-base parameters related to the cellular uptake mechanism. Very specific pH-sensitive Tc(V)-DMS accumulation only in the osteoclastic system was detected, and use of Tc(V)-DMS in the differential detection of osteoblastic and osteoclastic metastases is discussed.

  18. Distribution of trace metals in surface seawater and zooplankton of the Bay of Bengal, off Rushikulya estuary, East Coast of India

    International Nuclear Information System (INIS)

    Srichandan, Suchismita; Panigrahy, R.C.; Baliarsingh, S.K.; Srinivasa, Rao B.; Pati, Premalata; Sahu, Biraja K.; Sahu, K.C.

    2016-01-01

    Concentrations of trace metals such as iron (Fe), copper (Cu), zinc (Zn), cobalt (Co), nickel (Ni), manganese (Mn), lead (Pb), cadmium (Cd), chromium (Cr), arsenic (As), vanadium (V), and selenium (Se) were determined in seawater and zooplankton from the surface waters off Rushikulya estuary, north-western Bay of Bengal. During the study period, the concentration of trace metals in seawater and zooplankton showed significant spatio-temporal variation. Cu and Co levels in seawater mostly remained non-detectable. Other elements were found at higher concentrations and exhibited marked variations. The rank order distribution of trace metals in terms of their average concentration in seawater was observed as Fe > Ni > Mn > Pb > As > Zn > Cr > V > Se > Cd while in zooplankton it was Fe > Mn > Cd > As > Pb > Ni > Cr > Zn > V > Se. The bioaccumulation factor (BAF) of Fe was highest followed by Zn and the lowest value was observed with Ni. Results of correlation analysis discerned positive affinity and good relationship among the majority of the trace metals, both in seawater and zooplankton suggesting their strong affinity and coexistence. - Highlights: • First-hand report on trace metal concentration in zooplankton and seawater covering 2 years from this eco-sensitive region. • In seawater trace metals followed the rank order of Fe > Ni > Mn > Pb > As > Zn > Cr > V > Se > Cd. • In zooplankton the rank order was Fe > Mn > Cd > As > Pb > Ni > Cr > Zn > V > Se. • The bioaccumulation factor of Fe was highest followed by Zn. • Strong affinity, coexistence, and similar source of trace metals in the study area.

  19. Variations in concentrations and fluxes of dimethylsulfide (DMS) from the Indian estuaries

    Digital Repository Service at National Institute of Oceanography (India)

    Viswanadham, R.; Bharathi, M.D.; Sarma, V.V.S.S.

    to inhibition of phytoplankton growth by suspended load and low flushing rates. Key words: DMS; Fluxes; River discharge; Nutrients inputs; Indian Monsoonal estuaries 2    1. Introduction Dimethyl sulfide (DMS) is an important biogenic sulfur gas, produced....R. Dolan, and M. Corn. 1996. Assessment of the role of copepods and ciliates in the release to solution of particulate DMSP. Marine Ecology Progress Series 141: 119- 127. Dacey, J.W.H., and S.G. Wakeham. 1986. Oceanic dimethyl sulfide: production during...

  20. Exploring travelers' behavior in response to dynamic message signs (DMS) using a driving simulator : [research summary].

    Science.gov (United States)

    2013-10-16

    The Maryland State Highway Administration (SHA) uses dynamic message signs : (DMS) for traffic and incident management and for providing travel time information. : Previous research in Maryland has shown that a DMS can be an accurate, effective, and ...

  1. Discrimination of bacteria using pyrolysis-gas chromatography-differential mobility spectrometry (Py-GC-DMS) and chemometrics.

    Science.gov (United States)

    Cheung, William; Xu, Yu; Thomas, C L Paul; Goodacre, Royston

    2009-03-01

    Discrimination of bacteria was investigated using pyrolysis-gas chromatography-differential mobility spectrometry (Py-GC-DMS). Three strains belonging to the genus Bacillus were investigated and these included two strains of Bacillus subtilis and a single Bacillus megaterium. These were chosen so as to evaluate the possibility of bacterial strain discrimination using Py-GC-DMS. The instrument was constructed in-house and the long-term reproducibility of the instrument was evaluated over a period of 60 days using a Scotch whisky quality control. To assess the reproducibility further each bacterium was cultured six times and each culture was analysed in replicate to give three analytical replicates. The DMS data were generated in both positive and negative modes, and the data in each mode were analysed independently of each other. The Py-GC-DMS data were pre-processed via correlation optimised warping (COW) and asymmetric least square (ALS) to align the DMS chromatograms and to remove any unavoidable baseline shifts, prior to normalisation. Processed chromatograms were analysed using principal component analysis (PCA) followed by supervised learning methodology using partial least squares for discriminant analysis (PLS-DA). It was found that the separations between B. subtilis and B. megaterium can be readily observed by PCA; however, strain discrimination within the two B. subtilis was only possible using supervised learning. As multiple biological replicates were analysed an exhaustive splitting of the training and test sets was undertaken and this allowed correct classification rates (CCRs) to be assessed for the 3375 test sets. It was found that with PLS-DA the negative ion mode DMS data were more discriminatory than the positive mode data.

  2. PRODUCTION OF DMS FROM DISSOLVED DMSP IN AXENIC CULTURES OF THE MARINE-PHYTOPLANKTON SPECIES PHAEOCYSTIS SP

    NARCIS (Netherlands)

    STEFELS, J; VANBOEKEL, WHM

    In the marine environment, production of dimethylsulfide (DMS) from dissolved dimethylsulfoniopropionate (DMSP(d)) - an algal osmolyte - is thought to occur mainly through bacterial activity. We have investigated the possibility that phytoplankton cells convert DMSP(d) into DMS, using axenic batch

  3. DMS photochemistry during the Asian dust-storm period in the Spring of 2001: model simulations vs. field observations.

    Science.gov (United States)

    Shon, Zang-Ho; Kim, Ki-Hyun; Swan, Hilton; Lee, Gangwoong; Kim, Yoo-Keun

    2005-01-01

    This study examines the local/regional DMS oxidation chemistry on Jeju Island (33.17 degrees N, 126.10 degrees E) during the Asian dust-storm (ADS) period of April 2001. Three ADS events were observed during the periods of April 10-12, 13-14, and 25-26, respectively. For comparative purposes, a non-Asian-dust-storm (NADS) period was also considered in this study, which represents the entire measurement periods in April except the ADS events. The atmospheric concentrations of DMS and SO2 were measured at a ground station on Jeju Island, Korea, as part of the ACE-Asia intensive operation. DMS (means of 34-52 pptv) and SO2 (means of 0.96-1.14 ppbv) levels measured during the ADS period were higher than those (mean of 0.45 ppbv) during the NADS period. The enhanced DMS levels during the ADS period were likely due to the increase in DMS flux under reduced oxidant levels (OH and NO3). SO2 levels between the two contrasting periods were affected sensitively by some factors such as air mass origins. The diurnal variation patterns of DMS observed during the two periods were largely different from those seen in the background environment (e.g., the marine boundary layer (MBL)). In contrast to the MBL, the maximum DMS value during the ADS period was seen in the late afternoon at about sunset; this reversed pattern appears to be regulated by certain factors (e.g., enhanced NO3 oxidation). The sea-to-air fluxes of DMS between the ADS and NADS periods were calculated based on the mass-balance photochemical-modeling approach; their results were clearly distinguished with the values of 4.4 and 2.4 micromole m(-2) day(-1), respectively. This study confirmed that the contribution of DMS oxidation to observed SO2 levels on Jeju Island was not significant during our study period regardless of ADS or NADS periods.

  4. Radioactivity in the Exclusive Economic Zone of east coast Peninsular Malaysia. Distribution trends of 137Cs in surface seawater

    International Nuclear Information System (INIS)

    Zaharudin Ahmad; Zal U'yun Wan Mahmood; Hidayah Shahar; Mei Wo Yii; Ahmad Sanadi Abu Bakar

    2011-01-01

    Large volumes of surface seawater samples were collected from thirty locations in the Exclusive Economic Zone (EEZ) of the east coast Peninsular Malaysia on June 2008 to study the activity concentrations of 137 Cs. The results will serve as additional information to the existing baseline data and is very useful for monitoring fresh input of anthropogenic radionuclide into Malaysian marine environment. In this study, the activity concentrations of 137 Cs were determined using co-precipitation technique, followed by Gamma Spectrometry measurement. The mean activity concentration of 137 Cs ranged between 3.40 and 5.89 Bq/m 3 . Higher activity concentrations were observed at the coastal and towards the south of Peninsular Malaysia and were aligned with the high turbidity. These may due to the rapid diffusion of 137 Cs from suspended particulates and fine sediments into surface seawater. The activity concentrations of 137 Cs observed in this study were slightly higher than the concentrations reported in seawater at the Straits of Malacca, Vietnam and Philippines. This might be because the study area received more input of 137 Cs that originated from global fallout and then deposited on land which later being transported subsequently into the coastal zone due to siltation and erosion processes. It could also be attributed to the intrusion of river waters containing higher concentrations of 137 Cs. (author)

  5. Factor structure and psychometric properties of a Romanian translation of the drive for Muscularity Scale (DMS) in university men.

    Science.gov (United States)

    Swami, Viren; Vintila, Mona; Tudorel, Otilia; Goian, Cosmin; Barron, David

    2018-02-20

    We examined the psychometric properties of a Romanian translation of the 15-item Drive for Muscularity Scale (DMS). Male university students from Romania (N = 343) completed the DMS, as well as measures of self-esteem, body appreciation, and muscle discrepancy. Exploratory factor analysis indicated that DMS scores reduced to two factors that related to muscularity-oriented attitudes and behaviours, with both first-order factors loading onto a higher-order factor. However, confirmatory factor analysis indicated that a model with two first-order factors and a higher-order factor had poor fit. A two-factor model without a higher-order construct achieved acceptable but mediocre fit. Scores on the two-factor DMS model had adequate internal consistency and demonstrated acceptable convergent validity (significant correlations with self-esteem, body appreciation, and muscle discrepancy). These results provide support for a two-factor model of DMS scores in a Romanian-speaking sample and extends the availability of the DMS to a rarely-examined linguistic group. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. WRAP Module 1 data management system (DMS) software design description (SDD)

    International Nuclear Information System (INIS)

    Weidert, J.R.

    1996-01-01

    Revision 2 of the Waste Receiving and Processing (WRAP) Module 1 Data Management System (DMS) Preliminary Software Design Description (PSDD) provides a high-level design description of the system. The WRAP 1 DMS is required to collect, store, and report data related to certification, tracking, packaging, repackaging, processing, and shipment of waste processed or stored at the WRAP 1 facility. The WRAP 1 DMS SDD is used as the primary medium for communication software design information. This release provides design descriptions for the following process modules produced under Phase 1 of the development effort: Receiving Drum or Box Containers Process Routing and Picklists; Waste Inventory by Location and/or Container Relationships; LLW Process Glovebox Facility Radiologic Material Inventory Check (partial); Shipping (partial production); Drum or Box NDE Operations; and Drum or Box NDA Operations Data Review (partial production). In addition, design descriptions are included for the following process modules scheduled for development under Phases 2 and 3: Activity Comment; LLW RWM Glovebox Sample Management; TRU Process Glovebox; TRU RWM Glovebox; and TRUPACT Processing. Detailed design descriptions for Reports and Facility Metrics have also been provided for in Revision 2 of this document

  7. Seasonal changes in the abundance of bacterial genes related to dimethylsulfoniopropionate catabolism in seawater from Ofunato Bay revealed by metagenomic analysis

    KAUST Repository

    Kudo, Toshiaki; Kobiyama, Atsushi; Rashid, Jonaira; Reza, Shaheed; Yamada, Yuichiro; Ikeda, Yuri; Ikeda, Daisuke; Mizusawa, Nanami; Ikeo, Kazuho; Sato, Shigeru; Ogata, Takehiko; Jimbo, Mitsuru; Kaga, Shinnosuke; Watanabe, Shiho; Naiki, Kimiaki; Kaga, Yoshimasa; Segawa, Satoshi; Mineta, Katsuhiko; Bajic, Vladimir B.; Gojobori, Takashi; Watabe, Shugo

    2018-01-01

    Ofunato Bay is located in the northeastern Pacific Ocean area of Japan, and it has the highest biodiversity of marine organisms in the world, primarily due to tidal influences from the cold Oyashio and warm Kuroshio currents. Our previous results from performing shotgun metagenomics indicated that Candidatus Pelagibacter ubique and Planktomarina temperata were the dominant bacteria (Reza et al., 2018a, 2018b). These bacteria are reportedly able to catabolize dimethylsulfoniopropionate (DMSP) produced from phytoplankton into dimethyl sulfide (DMS) or methanethiol (MeSH). This study was focused on seasonal changes in the abundances of bacterial genes (dddP, dmdA) related to DMSP catabolism in the seawater of Ofunato Bay by BLAST+ analysis using shotgun metagenomic datasets. We found seasonal changes among the Candidatus Pelagibacter ubique strains, including those of the HTCC1062 type and the Red Sea type. A good correlation was observed between the chlorophyll a concentrations and the abundances of the catabolic genes, suggesting that the bacteria directly interact with phytoplankton in the marine material cycle system and play important roles in producing DMS and MeSH from DMSP as signaling molecules for the possible formation of the scent of the tidewater or as fish attractants.

  8. Seasonal changes in the abundance of bacterial genes related to dimethylsulfoniopropionate catabolism in seawater from Ofunato Bay revealed by metagenomic analysis

    KAUST Repository

    Kudo, Toshiaki

    2018-04-26

    Ofunato Bay is located in the northeastern Pacific Ocean area of Japan, and it has the highest biodiversity of marine organisms in the world, primarily due to tidal influences from the cold Oyashio and warm Kuroshio currents. Our previous results from performing shotgun metagenomics indicated that Candidatus Pelagibacter ubique and Planktomarina temperata were the dominant bacteria (Reza et al., 2018a, 2018b). These bacteria are reportedly able to catabolize dimethylsulfoniopropionate (DMSP) produced from phytoplankton into dimethyl sulfide (DMS) or methanethiol (MeSH). This study was focused on seasonal changes in the abundances of bacterial genes (dddP, dmdA) related to DMSP catabolism in the seawater of Ofunato Bay by BLAST+ analysis using shotgun metagenomic datasets. We found seasonal changes among the Candidatus Pelagibacter ubique strains, including those of the HTCC1062 type and the Red Sea type. A good correlation was observed between the chlorophyll a concentrations and the abundances of the catabolic genes, suggesting that the bacteria directly interact with phytoplankton in the marine material cycle system and play important roles in producing DMS and MeSH from DMSP as signaling molecules for the possible formation of the scent of the tidewater or as fish attractants.

  9. Specificity of pH sensitive Tc(V)-DMS for acidophilic osteoclastic bone cells: biological and cellular studies

    International Nuclear Information System (INIS)

    Horiuchi, K.; Konno, A.; Nishio, S.; Fukuda, Y.; Saji, H.; Hashimoto, K.

    2002-01-01

    Bone scintigraphy is a sensitive imaging method for detecting skeletal metastases but the low specificity has decreased its oncological use. Bone scintigraphy has relied on Tc-bisphosphonate (Tc-BP) agents with affinity for the mineral phase. However, bio-functional Tc(V)-DMS agent, sensitive to acid pH of tumoral tissue has shown osteotrophic properties, in adult bone pathologies. Objectives: Basis for understanding the osteotropic character of the pH sensitive Tc(V)-DMS in bone metastasis. Methods: Studies on differential Tc(V)-DMS and Tc-BP accumulation response were carried out by acidophilic osteoclast (OC) and basophilic osteoblast (OB) cells subjected to variable pH incubation media (HEPES, 37 0 C) and by bone tissue of Ehrlich Ascites Tumor (EAT) bearing mice, exposed to systemic NH4Cl or glucose mediated acidification (GmAc). Agents injected into tail vein and bone radioactivity analyzed. Bone metabolism markers measured in blood and urine (pH, Pi, Ca , Alp, Dpd). Acid-base regulation effect at cellular level, analyzed by using bafilomycin, amiloride, DIDS and acetazolamide inhibitors. Results: Lack of any OB response to acidification or alkalinization detected with either Tc(V)-DMS or Tc-BP agent. However, OC cells were highly sensitivity to acidification only in the presence of Tc(V)-DMS showing great radioactivity increase as the pH was lowered. This specificity also detected, in EAT bearing mice; increased bone tissue accumulation in response to systemic acidification was clearly detected upon administration of Tc(V)-DMS only under GmAc, an experimental model showing high urine excretion of deoxypyridinoline, a bone resorption marker. Conclusion: Peculiarity of multi nucleated OC cells sensitive to the environment pH and their activation in acid pH has been well known. Tc-BP agent showed lack of affinity for OC or OB cells. Specific affinity of OC cells for Tc(V)-DMS and its increased bone accumulation with the systemic pH lowering reflect the p

  10. A first appraisal of prognostic ocean DMS models and prospects for their use in climate models

    NARCIS (Netherlands)

    Le Clainche, Yvonnick; Vezina, Alain; Levasseur, Maurice; Cropp, Roger A.; Gunson, Jim R.; Vallina, Sergio M.; Vogt, Meike; Lancelot, Christiane; Allen, J. Icarus; Archer, Stephen D.; Bopp, Laurent; Deal, Clara; Elliott, Scott; Jin, Meibing; Malin, Gill; Schoemann, Veronique; Simo, Rafel; Six, Katharina D.; Stefels, Jacqueline

    2010-01-01

    Ocean dimethylsulfide (DMS) produced by marine biota is the largest natural source of atmospheric sulfur, playing a major role in the formation and evolution of aerosols, and consequently affecting climate. Several dynamic process-based DMS models have been developed over the last decade, and work

  11. Uranium from Seawater Program Review; Fuel Resources Uranium from Seawater Program DOE Office of Nuclear Energy

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-07-01

    For nuclear energy to remain sustainable in the United States, economically viable sources of uranium beyond terrestrial ores must be developed. The goal of this program is to develop advanced adsorbents that can extract uranium from seawater at twice the capacity of the best adsorbent developed by researchers at the Japan Atomic Energy Agency (JAEA), 1.5 mg U/g adsorbent. A multidisciplinary team from Oak Ridge National Laboratory, Lawrence Berkeley National Laboratory, Pacific Northwest National Laboratory, and the University of Texas at Austin was assembled to address this challenging problem. Polymeric adsorbents, based on the radiation grafting of acrylonitrile and methacrylic acid onto high surface-area polyethylene fibers followed by conversion of the nitriles to amidoximes, have been developed. These poly(acrylamidoxime-co-methacrylic acid) fibers showed uranium adsorption capacities for the extraction of uranium from seawater that exceed 3 mg U/g adsorbent in testing at the Pacific Northwest National Laboratory Marine Sciences Laboratory. The essence of this novel technology lies in the unique high surface-area trunk material that considerably increases the grafting yield of functional groups without compromising its mechanical properties. This technology received an R&D100 Award in 2012. In addition, high surface area nanomaterial adsorbents are under development with the goal of increasing uranium adsorption capacity by taking advantage of the high surface areas and tunable porosity of carbon-based nanomaterials. Simultaneously, de novo structure-based computational design methods are being used to design more selective and stable ligands and the most promising candidates are being synthesized, tested and evaluated for incorporation onto a support matrix. Fundamental thermodynamic and kinetic studies are being carried out to improve the adsorption efficiency, the selectivity of uranium over other metals, and the stability of the adsorbents. Understanding

  12. Effect of grazing-mediated dimethyl sulfide (DMS) production on the swimming behavior of the copepod Calanus helgolandicus.

    Science.gov (United States)

    Breckels, Mark N; Bode, Nikolai W F; Codling, Edward A; Steinke, Michael

    2013-07-15

    Chemical interactions play a fundamental role in the ecology of marine foodwebs. Dimethyl sulfide (DMS) is a ubiquitous marine trace gas that acts as a bioactive compound by eliciting foraging behavior in a range of marine taxa including the copepod Temora longicornis. Production of DMS can rapidly increase following microzooplankton grazing on phytoplankton. Here, we investigated whether grazing-induced DMS elicits an increase in foraging behavior in the copepod Calanus helgolandicus. We developed a semi-automated method to quantify the effect of grazing-mediated DMS on the proportion of the time budget tethered females allocate towards slow swimming, typically associated with feeding. The pooled data showed no differences in the proportion of the 25 min time budget allocated towards slow swimming between high (23.6 ± 9.74%) and low (29.1 ± 18.33%) DMS treatments. However, there was a high degree of variability between behavioral responses of individual copepods. We discuss the need for more detailed species-specific studies of individual level responses of copepods to chemical signals at different spatial scales to improve our understanding of chemical interactions between copepods and their prey.

  13. Perfluoroalkyl acids in surface seawater from the North Pacific to the Arctic Ocean: Contamination, distribution and transportation.

    Science.gov (United States)

    Li, Lei; Zheng, Hongyuan; Wang, Tieyu; Cai, Minghong; Wang, Pei

    2018-03-16

    The bioaccumulative, persistent and toxic properties of long-chain perfluoroalkyl acids (PFAAs) resulted in strict regulations on PFAAs, especially in developed countries. Consequently, the industry manufacturing of PFAAs shifts from long-chain to short-chain. In order to better understand the pollution situation of PFAAs in marine environment under this new circumstance, the occurrence of 17 linear PFAAs was investigated in 30 surface seawater samples from the North Pacific to Arctic Ocean (123°E to 24°W, 32 to 82°N) during the sixth Chinese Arctic Expedition in 2014. Total concentrations of PFAAs (∑PFAAs) were between 346.9 pg per liter (pg/L) to 3045.3 pg/L. The average concentrations of ∑PFAAs decreased in the order of East China Sea (2791.4 pg/L, n = 2), Sea of Japan (East Sea) (832.8 pg/L, n = 6), Arctic Ocean (516.9 pg/L, n = 7), Chukchi Sea (505.2 pg/L, n = 4), Bering Sea (501.2 pg/L, n = 8) and Sea of Okhotsk (417.7 pg/L, n = 3). C4 to C9 perfluoroalkyl carboxylic acids (PFCAs) were detected in more than 80% of the surface water samples. Perfluorobutanoic acid (PFBA) was the most prevalent compound and perfluorooctanoic acid (PFOA) was the second abundant homolog. The concentration of individual PFAAs in the surface seawater of East China Sea was much higher than other sampling seas. As the spatial distribution of PFAAs in the marine environment was mainly influenced by the river inflow from the basin countries, which proved the large input from China. Furthermore, the marginal seas of China were found with the greatest burden of PFOA comparing the pollution level in surface seawater worldwide. PFBA concentration in the surrounding seas of China was also high, but distributed more evenly with an obvious increase in recent years. This large-scale monitoring survey will help the improvement and development of PFAAs regulations and management, where production shift should be taken into consideration. Copyright

  14. Interacting effects of ocean acidification and warming on growth and DMS-production in the haptophyte coccolithophore Emiliania huxleyi.

    Science.gov (United States)

    Arnold, Hayley E; Kerrison, Philip; Steinke, Michael

    2013-04-01

    The production of the marine trace gas dimethyl sulfide (DMS) provides 90% of the marine biogenic sulfur in the atmosphere where it affects cloud formation and climate. The effects of increasing anthropogenic CO2 and the resulting warming and ocean acidification on trace gas production in the oceans are poorly understood. Here we report the first measurements of DMS-production and data on growth, DMSP and DMS concentrations in pH-stated cultures of the phytoplankton haptophyte Emiliania huxleyi. Four different environmental conditions were tested: ambient, elevated CO2 (+CO2 ), elevated temperature (+T) and elevated temperature and CO2 (+TCO2 ). In comparison to the ambient treatment, average DMS production was about 50% lower in the +CO2 treatment. Importantly, temperature had a strong effect on DMS production and the impacts outweighed the effects of a decrease in pH. As a result, the +T and +TCO2 treatments showed significantly higher DMS production of 36.2 ± 2.58 and 31.5 ± 4.66 μmol L(-1) cell volume (CV) h(-1) in comparison with the +CO2 treatment (14.9 ± 4.20 μmol L(-1) CV h(-1) ). As the cultures were aerated with an air/CO2 mixture, DMS was effectively removed from the incubation bottles so that concentration remained relatively low (3.6-6.1 mmol L(-1) CV). Intracellular DMSP has been shown to increase in E. huxleyi as a result of elevated temperature and/or elevated CO2 and our results are in agreement with this finding: the ambient and +CO2 treatments showed 125 ± 20.4 and 162 ± 27.7 mmol L(-1) CV, whereas +T and +TCO2 showed significantly increased intracellular DMSP concentrations of 195 ± 15.8 and 211 ± 28.2 mmol L(-1) CV respectively. Growth was unaffected by the treatments, but cell diameter decreased significantly under elevated temperature. These results indicate that DMS production is sensitive to CO2 and temperature in E. huxleyi. Hence, global environmental change that manifests in ocean acidification and warming may not result in

  15. Uptake of elements from seawater by ferromanganese crusts: Solid-phase associations and seawater speciation

    Science.gov (United States)

    Koschinsky, A.; Hein, J.R.

    2003-01-01

    Marine Fe-Mn oxyhydroxide crusts form by precipitation of dissolved components from seawater. Three hydrogenetic crust samples (one phosphatized) and two hydrothermal Mn-oxide samples were subjected to a sequential-leaching procedure in order to determine the host phases of 40 elements. Those host-phase associations are discussed with respect to element speciation in seawater. The partitioning of elements between the two major phases, Mn oxide and Fe oxyhydroxide, can in a first-order approximation be explained by a simple sorption model related to the inorganic speciation of the elements in seawater, as has been proposed in earlier models. Free and weakly complexed cations, such as alkali and alkaline earth metals, Mn, Co, Ni, Zn, T1(I), and partly Y, are sorbed preferentially on the negatively charged surface of the MnO2 in hydrogenetic crusts. The driving force is a strong coulombic interaction. All neutral or negatively charged chloro (Cd, Hg, T1), carbonate (Cu, Y, Pb, and U), and hydroxide (Be, Sc, Ti, Fe, Zr, Nb, In, Sn, Sb, Te, Hf, Ta, Bi, Th, and T1(III)) complexes and oxyanions (V, Cr, As, Se, Mo, and W) bind to the slightly positively charged surface of the amorphous FeOOH phase. While coulombic interaction can explain the sorption of the negatively charged species, the binding of neutral species is based on specific chemical interaction. Organic complexation of elements in deep-ocean water seems to be at most of minor importance. Surface oxidation can explain some strong metal associations, e.g. of Co and T1 with the MnO2 and Te with the FeOOH. Sorption reactions initially driven by coulombic forces are often followed by the formation of specific bonds between the adsorbate and the atoms of the oxide surface. Differences in the associations of some metals between the non-phosphatized and phosphatized hydrogenetic crusts and between the hydrogenetic and the hydrothermal samples reflect the different physico-chemical environments of formation and

  16. Microbial production and consumption of dimethyl sulfide (DMS) in a sea grass (Zostera noltii)-dominated marine intertidal sediment ecosystem (Bassin d'Arcachon, France)

    NARCIS (Netherlands)

    Jonkers, HM; van Bergeijk, SA; van Gemerden, H

    The relation between net dimethyl sulfide (DMS) production and changes in near surface (0-5 mm) oxygen concentrations in a sea grass (Zostera noltii Hornem)-covered intertidal sediment ecosystem was examined during a diel cycle. Sediment covered with Zostera was found to be more oxygenated than

  17. Environmental drivers of temporal variability in DMS (P) in the surfwater of a tropical intertidal beach

    Digital Repository Service at National Institute of Oceanography (India)

    Pandey, S.S.; LokaBharathi, P.A.

    show that the average DMS concentration was highest during the monsoon season (7.64nM) followed by post-monsoon (6.71nM) and premonsoon(1.58nM) Consequently, the estimated sea-air flux of DMS is monsoon > post-monsoon > pre-monsoon at 24.75> 18.93> 2...

  18. Improving DMS 9210 requirements for limestone rock asphalt - final report.

    Science.gov (United States)

    2015-03-01

    Limestone Rock Asphalt (LRA) mixtures have been produced and placed for several decades using : specification requirements currently listed under DMS 9210. Several districts have had placement issues : and premature failures at the beginning of 2010....

  19. Fuel Production from Seawater and Fuel Cells Using Seawater.

    Science.gov (United States)

    Fukuzumi, Shunichi; Lee, Yong-Min; Nam, Wonwoo

    2017-11-23

    Seawater is the most abundant resource on our planet and fuel production from seawater has the notable advantage that it would not compete with growing demands for pure water. This Review focuses on the production of fuels from seawater and their direct use in fuel cells. Electrolysis of seawater under appropriate conditions affords hydrogen and dioxygen with 100 % faradaic efficiency without oxidation of chloride. Photoelectrocatalytic production of hydrogen from seawater provides a promising way to produce hydrogen with low cost and high efficiency. Microbial solar cells (MSCs) that use biofilms produced in seawater can generate electricity from sunlight without additional fuel because the products of photosynthesis can be utilized as electrode reactants, whereas the electrode products can be utilized as photosynthetic reactants. Another important source for hydrogen is hydrogen sulfide, which is abundantly found in Black Sea deep water. Hydrogen produced by electrolysis of Black Sea deep water can also be used in hydrogen fuel cells. Production of a fuel and its direct use in a fuel cell has been made possible for the first time by a combination of photocatalytic production of hydrogen peroxide from seawater and dioxygen in the air and its direct use in one-compartment hydrogen peroxide fuel cells to obtain electric power. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Boundary layer and free-tropospheric dimethyl sulfide in the Arctic spring and summer

    Directory of Open Access Journals (Sweden)

    R. Ghahremaninezhad

    2017-07-01

    Full Text Available Vertical distributions of atmospheric dimethyl sulfide (DMS(g were sampled aboard the research aircraft Polar 6 near Lancaster Sound, Nunavut, Canada, in July 2014 and on pan-Arctic flights in April 2015 that started from Longyearbyen, Spitzbergen, and passed through Alert and Eureka, Nunavut, and Inuvik, Northwest Territories. Larger mean DMS(g mixing ratios were present during April 2015 (campaign mean of 116  ±  8 pptv compared to July 2014 (campaign mean of 20  ±  6 pptv. During July 2014, the largest mixing ratios were found near the surface over the ice edge and open water. DMS(g mixing ratios decreased with altitude up to about 3 km. During April 2015, profiles of DMS(g were more uniform with height and some profiles showed an increase with altitude. DMS reached as high as 100 pptv near 2500 m. Relative to the observation averages, GEOS-Chem (www.geos-chem.org chemical transport model simulations were higher during July and lower during April. Based on the simulations, more than 90 % of the July DMS(g below 2 km and more than 90 % of the April DMS(g originated from Arctic seawater (north of 66° N. During April, 60 % of the DMS(g, between 500 and 3000 m originated from Arctic seawater. During July 2014, FLEXPART (FLEXible PARTicle dispersion model simulations locate the sampled air mass over Baffin Bay and the Canadian Arctic Archipelago 4 days back from the observations. During April 2015, the locations of the air masses 4 days back from sampling were varied: Baffin Bay/Canadian Archipelago, the Arctic Ocean, Greenland and the Pacific Ocean. Our results highlight the role of open water below the flight as the source of DMS(g during July 2014 and the influence of long-range transport (LRT of DMS(g from further afield in the Arctic above 2500 m during April 2015.

  1. Strontium (Sr) separation from seawater using titanate adsorbents: Effects of seawater matrix ions on Sr sorption behavior

    Science.gov (United States)

    Ryu, Jungho; Hong, Hye-jin; Ryu, Taegong; Park, In-Su

    2017-04-01

    Strontium (Sr) which has many industrial applications such as ferrite magnet, ceramic, and fire works exists in seawater with the concentration of approximately 7 mg/L. In previous report estimating economic potential on recovery of various elements from seawater in terms of their commercial values and concentrations in seawater, Sr locates upper than approximate break-even line, which implies Sr recovery from seawater can be potentially profitable. Recently, Sr separation from seawater has received great attention in the environmental aspect after Fukushima Nuclear Power Plant (NPP) accident which released much amount of radioactive Sr and Cs. Accordingly, the efficient separation of radioactive elements released to seawater has become critical as an important technological need as well as their removal from radioactive wastes. So far, it has been introduced to separate Sr from aqueous media by various methods including solvent extraction, adsorption by solid materials, and ion exchange. Among them, the adsorption technique using solid adsorbents is of great interest for selectively separating Sr from seawater with respect to low concentration level of Sr. In this study, we synthesized titanate nanotube (TiNT) by simple hydrothermal reaction, characterized its physicochemical properties, and systematically evaluated Sr sorption behavior under various reaction conditions corresponding to seawater environment. The synthesized TiNT exhibited the fibril-type nanotube structure with high specific surface area of 260 m2/g. The adsorption of Sr on TiNT rapidly occurred following pseudo-second-order kinetic model, and was in good agreement with Langmuir isotherm model, indicating maximum adsorption capacity of 97 mg/g. Based on Sr uptake and Na release with stoichiometric balance, sorption mechanism of Sr on TiNT was found to be ion-exchange between Na in TiNT lattice and Sr in solution phase, which was also confirmed by XRD and Raman analysis. Among competitive ions, Ca

  2. Supervised Semi-Automated Data Analysis Software for Gas Chromatography / Differential Mobility Spectrometry (GC/DMS) Metabolomics Applications.

    Science.gov (United States)

    Peirano, Daniel J; Pasamontes, Alberto; Davis, Cristina E

    2016-09-01

    Modern differential mobility spectrometers (DMS) produce complex and multi-dimensional data streams that allow for near-real-time or post-hoc chemical detection for a variety of applications. An active area of interest for this technology is metabolite monitoring for biological applications, and these data sets regularly have unique technical and data analysis end user requirements. While there are initial publications on how investigators have individually processed and analyzed their DMS metabolomic data, there are no user-ready commercial or open source software packages that are easily used for this purpose. We have created custom software uniquely suited to analyze gas chromatograph / differential mobility spectrometry (GC/DMS) data from biological sources. Here we explain the implementation of the software, describe the user features that are available, and provide an example of how this software functions using a previously-published data set. The software is compatible with many commercial or home-made DMS systems. Because the software is versatile, it can also potentially be used for other similarly structured data sets, such as GC/GC and other IMS modalities.

  3. Mercury isotope fractionation during transfer from post-desulfurized seawater to air.

    Science.gov (United States)

    Huang, Shuyuan; Lin, Kunning; Yuan, Dongxing; Gao, Yaqin; Sun, Lumin

    2016-12-15

    Samples of dissolved gaseous mercury (DGM) in the post-desulfurized seawater discharged from a coal-fired power plant together with samples of gaseous elemental mercury (GEM) over the post-desulfurized seawater surface were collected and analyzed to study the mercury isotope fractionation during transfer from post-desulfurized seawater to air. Experimental results showed that when DGM in the seawater was converted to GEM in the air, the δ 202 Hg and Δ 199 Hg values were changed, ranging from -2.98 to -0.04‰ and from -0.31 to 0.64‰, respectively. Aeration played a key role in accelerating the transformation of DGM to GEM, and resulted in light mercury isotopes being more likely to be enriched in the GEM. The ratio Δ 199 Hg/Δ 201 Hg was 1.626 in all samples, suggesting that mercury mass independent fractionation occurred owing to the nuclear volume effect during the transformation. In addition, mass independent fractionation of mercury even isotopes was found in the GEM above the post-desulfurized seawater surface in the aeration pool. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Spatial variations of DMS, DMSP and phytoplankton in the Bay of Bengal during the summer monsoon 2001

    Digital Repository Service at National Institute of Oceanography (India)

    Shenoy, D.M.; Paul, J.T.; Gauns, M.; Ramaiah, N.; DileepKumar, M.

    in the radiation balance of the earth. During the summer monsoon of 2001 measurements were made for DMS and DMSPt (total DMSP) together with related biological parameters in the Bay of Bengal. Both DMS and DMSPt were restricted to the upper 40 m of the water column...

  5. Annual cycle of the production and fate of DMS and DMSP in a marine coastal system

    NARCIS (Netherlands)

    Kwint, RLJ; Kramer, KJM

    The production of DMSP by phytoplankton and the fate through the marine system of both DMSP and DMS were followed for a period of 21 mo in the natural environment by studying a Wadden Sea tidal inlet. The major production and emission of DMS appeared to be Limited to a period of only 2 mo, which was

  6. Surfactant induced complex formation and their effects on the interfacial properties of seawater.

    Science.gov (United States)

    Guzmán, Eduardo; Santini, Eva; Benedetti, Alessandro; Ravera, Francesca; Ferrari, Michele; Liggieri, Libero

    2014-11-01

    The effect of a cationic surfactant, hexadecyltrimethylammonium bromide (CTAB), on the interfacial properties of seawater has been studied by dynamic and equilibrium surface tension and by dilational rheology essays. Important modifications of the surface tension and dilational rheology response have been observed already at the very low CTAB concentrations, where the effects due to the high ionic strength are negligible. The comparison with the effects of CTAB in different seawater models, or in natural seawater fractions, points out the establishment of strong interactions between the surfactant molecules and the lipophilic fraction of organic material dispersed/dissolved in seawater, affecting the interfacial activity of the molecules. Considering the biochemical richness of seawater, these results can be explained assuming interaction mechanisms and adsorption schemes similar to those speculated for protein and other macromolecules in the presence of surfactants, which in fact show similar features. Thus already at the low concentrations the surfactant molecules form highly surface-active complexes with part of the organic fraction of seawater. At the larger surfactant concentrations these complexes compete for adsorption with an excess of free CTAB molecules which, according to the thermodynamic conditions, are most favoured to occupy the liquid interface. The results of this study underline the important role of the sea organic content in enhancing the surface-activity of surfactants, which is relevant for a deeper understand of the direct and indirect effects of these types of pollutants on the physico-chemical environment in the sea coastal areas and develop mitigation strategies. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Influence of non-smooth surface on tribological properties of glass fiber-epoxy resin composite sliding against stainless steel under natural seawater lubrication

    Science.gov (United States)

    Wu, Shaofeng; Gao, Dianrong; Liang, Yingna; Chen, Bo

    2015-11-01

    With the development of bionics, the bionic non-smooth surfaces are introduced to the field of tribology. Although non-smooth surface has been studied widely, the studies of non-smooth surface under the natural seawater lubrication are still very fewer, especially experimental research. The influences of smooth and non-smooth surface on the frictional properties of the glass fiber-epoxy resin composite (GF/EPR) coupled with stainless steel 316L are investigated under natural seawater lubrication in this paper. The tested non-smooth surfaces include the surfaces with semi-spherical pits, the conical pits, the cone-cylinder combined pits, the cylindrical pits and through holes. The friction and wear tests are performed using a ring-on-disc test rig under 60 N load and 1000 r/min rotational speed. The tests results show that GF/EPR with bionic non-smooth surface has quite lower friction coefficient and better wear resistance than GF/EPR with smooth surface without pits. The average friction coefficient of GF/EPR with semi-spherical pits is 0.088, which shows the largest reduction is approximately 63.18% of GF/EPR with smooth surface. In addition, the wear debris on the worn surfaces of GF/EPR are observed by a confocal scanning laser microscope. It is shown that the primary wear mechanism is the abrasive wear. The research results provide some design parameters for non-smooth surface, and the experiment results can serve as a beneficial supplement to non-smooth surface study.

  8. 14 CFR 406.113 - Filing documents with the Docket Management System (DMS) and sending documents to the...

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Filing documents with the Docket Management System (DMS) and sending documents to the administrative law judge and Assistant Chief Counsel for... Management System (DMS) and sending documents to the administrative law judge and Assistant Chief Counsel for...

  9. A coastal surface seawater analyzer for nitrogenous nutrient mapping

    Science.gov (United States)

    Masserini, Robert T.; Fanning, Kent A.; Hendrix, Steven A.; Kleiman, Brittany M.

    2017-11-01

    Satellite-data-based modeling of chlorophyll indicates that ocean waters in the mesosphere category are responsible for the majority of oceanic net primary productivity. Coastal waters, which frequently have surface chlorophyll values in the mesosphere range and have strong horizontal chlorophyll gradients and large temporal variations. Thus programs of detailed coastal nutrient surveys are essential to the study of the dynamics of oceanic net primary productivity, along with land use impacts on estuarine and coastal ecosystems. The degree of variability in these regions necessitates flexible instrumentation capable of near real-time analysis to detect and monitor analytes of interest. This work describes the development of a portable coastal surface seawater analyzer for nutrient mapping that can simultaneously elucidate with high resolution the distribution of nitrate, nitrite, and ammonium - the three principal nitrogenous inorganic nutrients in coastal systems. The approach focuses on the use of pulsed xenon flash lamps to construct an analyzer which can be adapted to any automated chemistry with fluorescence detection. The system has two heaters, on-the-fly standardization, on-board data logging, an independent 24 volt direct current power supply, internal local operating network, a 12 channel peristaltic pump, four rotary injection/selection valves, and an intuitive graphical user interface. Using the methodology of Masserini and Fanning (2000) the detection limits for ammonium, nitrite, and nitrate plus nitrite were 11, 10, and 22 nM, respectively. A field test of the analyzer in Gulf of Mexico coastal waters demonstrated its ability to monitor and delineate the complexity of inorganic nitrogen nutrient enrichments within a coastal system.

  10. Overview and preliminary results of the Surface Ocean Aerosol Production (SOAP campaign

    Directory of Open Access Journals (Sweden)

    C. S. Law

    2017-11-01

    Full Text Available Establishing the relationship between marine boundary layer (MBL aerosols and surface water biogeochemistry is required to understand aerosol and cloud production processes over the remote ocean and represent them more accurately in earth system models and global climate projections. This was addressed by the SOAP (Surface Ocean Aerosol Production campaign, which examined air–sea interaction over biologically productive frontal waters east of New Zealand. This overview details the objectives, regional context, sampling strategy and provisional findings of a pilot study, PreSOAP, in austral summer 2011 and the following SOAP voyage in late austral summer 2012. Both voyages characterized surface water and MBL composition in three phytoplankton blooms of differing species composition and biogeochemistry, with significant regional correlation observed between chlorophyll a and DMSsw. Surface seawater dimethylsulfide (DMSsw and associated air–sea DMS flux showed spatial variation during the SOAP voyage, with maxima of 25 nmol L−1 and 100 µmol m−2 d−1, respectively, recorded in a dinoflagellate bloom. Inclusion of SOAP data in a regional DMSsw compilation indicates that the current climatological mean is an underestimate for this region of the southwest Pacific. Estimation of the DMS gas transfer velocity (kDMS by independent techniques of eddy covariance and gradient flux showed good agreement, although both exhibited periodic deviations from model estimates. Flux anomalies were related to surface warming and sea surface microlayer enrichment and also reflected the heterogeneous distribution of DMSsw and the associated flux footprint. Other aerosol precursors measured included the halides and various volatile organic carbon compounds, with first measurements of the short-lived gases glyoxal and methylglyoxal in pristine Southern Ocean marine air indicating an unidentified local source. The application of a real-time clean sector

  11. Speciation of cadmium in seawater - a direct voltammetric approach

    International Nuclear Information System (INIS)

    Helmers, E.

    1994-01-01

    The present report deals with differential pulse anodic stripping voltammetry (DPASV) applied for the analysis of cadmium in open ocean seawater. Evaluation of different Cd species can generate information about distribution and speciation of Cd in the open ocean. Distribution of Cd was investigated in surface waters of the Atlantic Ocean over a wide geographical range as well as in the water column. Surface water sampling on board the research vessel Polarstern was performed from the bow boom of the ship as well as with a snorkel system which allowed continuous sample-taking. Two different Cd species could be differentiated in the voltammograms. UV-irradiation experiments allowed the identification of an inorganic and organic Cd form, the latter caused by the association between Cd and organic matter as e.g. humic substances (HS). Atlantic ocean surface seawater normally contains between 2 and 4 ng organically complexed Cd/kg and no detectable inorganic Cd. Some areas however showed readings of up to 14 ng inorganic Cd/kg in addition. Water column samples exhibited an enrichment of inorganic Cd by depth. Occurrence of inorganic Cd at the surface could be related to specific oceanographical conditions. Together with analytical results of trace metal contents in the particulate phases of surface seawater, new aspects could be established about the biogeochemical cycling of Cd in the sea. (orig.)

  12. A study on antifouling technique through seawater electrolyzing reaction on ship hull surface 【Article】

    OpenAIRE

    Huang, Yi; Saito, Kimio; Usami, Masahiro

    2003-01-01

    The antifouling technique through seawater electrolysis for ship hulls may be realized by an antifoul-ing system consisting of a power unit and the electro-conductive film. In the electric field formed bysuch an antifouling system, besides that both the electro-conductive film layer sub-region and the sea-water sub-region are included, polarization occurs on the interface between electro-conductive film layerand seawater. Therefore, based on the Interface Electro-Double Layer theory, a numeri...

  13. Corrosion of aluminum alloys in ocean thermal energy conversion seawaters

    International Nuclear Information System (INIS)

    Larsen-Basse, J.

    1984-01-01

    Aluminum alloys 5052, 3004, and Alclad 3003 and 3004 were exposed to flowing seawater at 2.44 m/s (8 fps) at the Seacoast Test Facility on Hawaii. One year data for warm surface water and three mouth data for cold water from 600 m depth are reported for free fouling, chlorinated and sponge ball cleaned conditions. All alloys pit in deep seawater, but show no pitting in warm surface water. Uniform corrosion in the warm water is initially rapid, but after 25 to 30 days the rate becomes slower and extrapolated 30 year material losses are in the 125 to 215 μm range. Chlorination at a level of 0.05 ppm for one hour per day has only a minor effect on corrosion rates, while sponge ball cleaning leads to erosion-corrosion of the Alclad surfaces and has no effect on alloy 5052. The need for additional testing in tropical seawater is discussed, as is the need for an improved understanding of the formation of inorganic scale films, their properties, and their effect on corrosion rates and heat transfer

  14. Characterization of ion processes in a GC/DMS air quality monitor by integration of the instrument to a mass spectrometer.

    Science.gov (United States)

    Limero, T F; Nazarov, E G; Menlyadiev, M; Eiceman, G A

    2015-02-07

    The air quality monitor (AQM), which included a portable gas chromatograph (GC) and a detector was interfaced to a mass spectrometer (MS) by introducing flow from the GC detector to the atmospheric pressure ion source of the MS. This small GC system, with a gas recirculation loop for carrier and detector make-up gases, comprised an inlet to preconcentrate volatile organic compounds (VOCs) in air, a thermal desorber before the GC column, a differential mobility spectrometer (DMS), and another DMS as an atmospheric pressure ionization source for the MS. Return flow to the internally recirculated air system of the AQM's DMS was replenished using purified air. Although ions and unreacted neutral vapors flowed from the detector through Viton® tubing into the source of the MS, ions were not detected in the MS without the auxillary ion source, (63)Ni as in the mobility detector. The GC-DMS-MS instrument provided a 3-D measurement platform (GC, DMS, and MS analysis) to explore the gas composition inside the GC-DMS recirculation loop and provide DMS-MS measurement of the components of a complex VOC mixture with performance significantly enhanced by mass-analysis, either with mass spectral scans or with an extracted ion chromatogram. This combination of a mobility spectrometer and a mass spectrometer was possible as vapors and ions are carried together through the DMS analyzer, thereby preserving the chromatographic separation efficiency. The critical benefit of this instrument concept is that all flows in and through the thoroughly integrated GC-DMS analyzer are kept intact allowing a full measure of the ion and vapor composition in the complete system. Performance has been evaluated using a synthetic air sample and a sample of airborne vapors in a laboratory. Capabilities and performance values are described using results from AQM-MS analysis of purified air, ambient air from a research laboratory in a chemistry building, and a sample of synthetic air of known composition

  15. [The DMS 48: norms and diagnostic proprieties for Alzheimer's disease in elderly population from the AMI cohort study].

    Science.gov (United States)

    Rullier, Laetitia; Matharan, Fanny; Barbeau, Emmanuel J; Mokri, Hind; Dartigues, Jean-François; Pérès, Karine; Amieva, Hélène

    2014-09-01

    The DMS 48 is a visual recognition memory test designed to detect memory changes in early Alzheimer's disease (AD). The aim of this study was to produce normative scores for this test and to assess its psychometric properties in the detection of AD by comparison with a widely used test of verbal episodic memory: the story recall task of the Wechsler memory scale. Methods. Data were collected in a sample of 1002 agricultural retirees, aged 65 years and over, included in the AMI study, a population-based cohort conducted in Southwestern France. The sample used to establish normative data included 750 non-demented elderly while the sample used to study the properties of the test to detect AD included 751 participants whose 34 with AD. To assess AD detection accuracy, DMS 48 was compared to the Wechsler story recall task. Results. Age, sex, and education were significantly associated with DMS 48 performances. Therefore, normative scores were calculated according to sex, age, and educational level, and described by percentiles. Regarding the test properties for AD detection, DMS 48 presented a good balance between sensitivity (Se) and specificity (Sp) both for immediate (Se=70.6%; Sp=79.6%) and delayed recall (Se=79.4%; Sp=72.9%). It also showed high negative predictive values, around 98.5% for both recalls. Detection values were roughly similar to that of Wechsler story recall task. The DMS 48 seems to be as reliable as the Wechsler story recall task with similar detection properties. The DMS 48 is a test easy to administer in clinical situations and could be a helpful tool for AD screening.

  16. Identification and characterization of 1,4-dioxane-degrading microbe separated from surface seawater by the seawater-charcoal perfusion apparatus.

    Science.gov (United States)

    Matsui, Ryotaro; Takagi, Kazuhiro; Sakakibara, Futa; Abe, Tomoko; Shiiba, Kiwamu

    2016-06-01

    To determine the concentration of soluble 1,4-dioxane during biodegradation, a new method using of high-performance liquid chromatography equipped with a hydrophilic interaction chromatography column was developed. The developed method enabled easy and rapid determination of 1,4-dioxane, even in saline medium. Microbes capable of degrading 1,4-dioxane were selected from the seawater samples by the seawater-charcoal perfusion apparatus. Among 32 candidate 1,4-dioxane degraders,, strain RM-31 exhibited the strongest 1,4-dioxane degradation ability. 16S rDNA sequencing and the similarity analysis of strain RM-31 suggested that this organism was most closely related to Pseudonocardia carboxydivorans. This species is similar to Pseudonocardia dioxanivorans, which has previously been reported as a 1,4-dioxane degrader. Strain RM-31 could degrade 300 mg/L within 2 days. As culture incubation times increasing, the residual 1,4-dioxane concentration was decreasing and the total protein contents extracted from growth cells were increasing. The optimum initial pH of the broth medium and incubation temperature for 1,4-dioxane degradation were pH 6-8 and 25 °C. The biodegradation rate of 1,4-dioxane by strain RM-31 at 25 °C in broth medium with 3 % NaCl was almost 20 % faster than that without NaCl. It was probably a first bacteria from the seawater that can exert a strong degrading ability.

  17. Technical note: Examining ozone deposition over seawater

    Science.gov (United States)

    Surface layer resistance plays an important role in determining ozone deposition velocity over sea-water and can be influenced by chemical interactions at the air-water interface. Here, we examine the effect of chemical interactions of iodide, dimethylsulfide, dissolved organic c...

  18. Sublethal concentrations of the platinum(II) complex [Pt(O,O'-acac)(gamma-acac)(DMS)] alter the motility and induce anoikis in MCF-7 cells.

    Science.gov (United States)

    Muscella, Antonella; Calabriso, Nadia; Vetrugno, Carla; Urso, Loredana; Fanizzi, Francesco Paolo; De Pascali, Sandra Angelica; Marsigliante, Santo

    2010-07-01

    We showed previously that a new Pt(II) complex ([Pt(O,O'-acac)(gamma-acac)(DMS)]) exerted high and fast apoptotic processes in MCF-7 cells. The objective of this study was to investigate the hypothesis that [Pt(O,O'-acac)(gamma-acac)(DMS)] is also able to exert anoikis and alter the migration ability of MCF-7 cells, and to show some of the signalling events leading to these alterations. Cells were treated with sublethal doses of [Pt(O,O'-acac)(gamma-acac)(DMS)], and the efficiency of colony initiation and anchorage-independent growth was assayed; cell migration was examined by in vitro culture wounding assay. Gelatin zymography for MMP-2 and -9 activities, Western blottings of MMPs, MAPKs, Src, PKC-epsilon and FAK, after [Pt(O,O'-acac)(gamma-acac)(DMS)] treatment, were also performed. Sub-cytotoxic drug concentrations decreased the: (i) anchorage-dependent and -independent growth; (ii) migration ability; and (iii) expression and activity of MMP-2 and MMP-9. [Pt(O,O'-acac)(gamma-acac)(DMS)] provoked the generation of reactive oxygen species (ROS), and the activation of p38MAPK, Src and PKC-epsilon. p38MAPK phosphorylation, cell anoikis and migration due to [Pt(O,O'-acac)(gamma-acac)(DMS)] were blocked by PKC-epsilon inhibition. Furthermore, Src inhibition blocked the [Pt(O,O'-acac)(gamma-acac)(DMS)]-provoked activation of PKC-epsilon, while ROS generation blockage inhibited the activation of Src, and also the decrement of phosphorylated FAK observed in detached [Pt(O,O'-acac)(gamma-acac)(DMS)]-treated cells. Sublethal concentrations of [Pt(O,O'-acac)(gamma-acac)(DMS)] induced anoikis and prevented events leading to metastasis via alterations in cell migration, anchorage independency, stromal interactions and MMP activity. Hence, [Pt(O,O'-acac)(gamma-acac)(DMS)] may be a promising therapeutic agent for preventing growth and metastasis of breast cancer.

  19. Radiation influence on heterogenous processes in stainless steel contact with sea-water

    International Nuclear Information System (INIS)

    Agayev, T.N.; Garibov, A.A.; Velibekova, G.Z.; Aliyev, A.Q.; Aliyev, S.M.

    2005-01-01

    Full text: Austenitic stainless steel (s.s.) with Cr content 16 %, Ni - 15 % is widely used in nuclear reactors as construction material, for fuel cladding production and also is used in oil and gas production and transportation. They possess comparatively large section of slow neutron capture and as a result high corrosion resistance. In real exploitation condition of nuclear reactors s.s. are exposed to ionizing radiation influence in contact of different media. That's why during their corrosion and destruction processes the surface defect formation processes and further heterogenous processes with their participation are of great importance. The research results of mechanism during radiation-heterogenous processes in nuclear reactor stainless steel contact with sea-water under the influence of γ-radiation in temperature interval 300-1074 K are represented in the given work. Radiolytic processes in water are comprehensively studied and therefore it was taken as model system for dating the surface defects and secondary electrons emitted from metal. The same model system was applied also in sea-water radiolysis processes. It's been established that radiation processes in s.s. lead to molecular hydrogen yield increase and at T=300 K up to 6.5 molec./100 eV. With the temperature increase molecular hydrogen yield increase up to 25.3 molec./100 eV at T≤773 K. During the further temperature increase up to 1073 K radiation constituent of radiation-thermal process in comparison with thermal becomes unnoticeable and W T (H 2 )≅W p (H 2 ). The kinetics of oxide phase formation of investigated sample surface in the result of thermal and radiation-thermal processes in their contact with sea-water has been studied. At that it's been shown that radiation leads to protective oxidation process rate increase and promotes the beginning of stainless steel destruction oxidation in contact with sea-water. At T≥573 K insoluble oxide phase is formed on metal surface that promotes

  20. Yields of aerosol precursor substances by the oxidation of DMS as a function of atmospheric conditions (temperature and NOx). Final report; Ausbeuten von Aerosolvorlaeufersubstanzen bei der DMS-Oxidation als Funktion von atmosphaerischen Bedingungen (Temperatur und NO{sub x}). Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, I.; Albu, M.; Arsene, C.; Butkovskaya, N.I.; Patroescu, I.V.

    2002-04-28

    In-depth analyses have been made of the products and aerosol formation from the OH-radical initiated oxidation of dimethyl sulphide (CH3SCH3: DMS) as a function of temperature, O2 partial pressure and initial NO concentration in large photoreactors. The investigations have provided new insights into the oxidation mechanisms of both DMS and DMSO, e.g., it has been shown that interactions of the DMS-OH adduct with O2 form DMSO in the absence of NO and dimethyl sulphone (CH3SO2CH3: DMSO2) in its presence. The data support an SO2 yield of around 70% from OH + DMS in the remote marine atmosphere. Investigations on the OH-radical initiated oxidation of dimethyl sulphoxide (CH3SOCH3: DMSO) have shown for the first time that methane sulphinic acid (CH3S(O)OH: MSIA) is the major product. Within the experimental conditions employed in the experiments only a modest dependence of the aerosol yield on temperature and initial NO concentration was observed. The experiments support that sulphuric acid formed from OH + SO2 is the major component of the aerosol with only minor contributions from MSA and MSIA. The mechanistic information is being incorporated into a DMS atmospheric chemistry modeule for CTMs (http://www.dmi.dk/f+u/luft/eng/elcid/elcid.html) and also in a simplified form for a global climate model (http://ask.ii.uib.no/.climate/elcid/). (orig.)

  1. Spartina alterniflora alters ecosystem DMS and CH4 emissions and their relationship along interacting tidal and vegetation gradients within a coastal salt marsh in Eastern China

    Science.gov (United States)

    Wang, Jinxin; Wang, Jinshu

    2017-10-01

    Invasive Spartina alterniflora accumulates organic carbon rapidly and can utilize a wide range of potential precursors for dimethyl sulfide (DMS) production, as well as a wide variety of methanogenic substrates. Therefore, we predicted that S. alterniflora invasion would alter the relationships between DMS and methane (CH4) fluxes along the interacting gradients of tidal influence and vegetation, as well as the ecosystem-atmosphere exchange of DMS and CH4. In this study, we used static flux chambers to measure DMS and CH4 fluxes in August (growing season) and December (non-growing season) of 2013, along creek and vegetation transects in an Eastern Chinese coastal salt marsh. S. alterniflora invasion dramatically increased DMS and CH4 emission rates by 3.8-513.0 and 2.0-127.1 times the emission rates within non-vegetated regions and regions populated with native species, respectively, and significantly altered the spatial distribution of DMS and CH4 emissions. We also observed a substantial amount of variation in the DMS and CH4 fluxes along the elevation gradient in the salt marsh studied. A significant relationship between DMS and CH4 fluxes was observed, with the CH4 flux passively related to the DMS flux. The correlation between CH4 and DMS emissions along the vegetation transects was more significant than along the tidal creek. In the S. alterniflora salt marsh, the relationship between DMS and CH4 fluxes was more significant than within any other salt marsh. Additionally, CH4 emissions within the S. alterniflora salt marsh were more sensitive to the variation in DMS emissions than within any other vegetation zone. The spatial variability in the relationship observed between DMS and CH4 fluxes appears to be at least partly due to the alteration of substrates involved in DMS and CH4 by S. alterniflora invasion. In the S. alterniflora salt marsh, methanogenesis was more likely to be derived from non-competitive substrates than competitive substrates, but within

  2. Uranium from seawater

    International Nuclear Information System (INIS)

    Gregg, D.; Folkendt, M.

    1982-01-01

    A novel process for recovering uranium from seawater is proposed and some of the critical technical parameters are evaluated. The process, in summary, consists of two different options for contacting adsorbant pellets with seawater without pumping the seawater. It is expected that this will reduce the mass handling requirements, compared to pumped seawater systems, by a factor of approximately 10 5 , which should also result in a large reduction in initial capital investment. Activated carbon, possibly in combination with a small amount of dissolved titanium hydroxide, is expected to be the preferred adsorbant material instead of the commonly assumed titanium hydroxide alone. The activated carbon, after exposure to seawater, can be stripped of uranium with an appropriate eluant (probably an acid) or can be burned for its heating value (possible in a power plant) leaving the uranium further enriched in its ash. The uranium, representing about 1% of the ash, is then a rich ore and would be recovered in a conventional manner. Experimental results have indicated that activated carbon, acting alone, is not adequately effective in adsorbing the uranium from seawater. We measured partition coefficients (concentration ratios) of approximately 10 3 in seawater instead of the reported values of 10 5 . However, preliminary tests carried out in fresh water show considerable promise for an extraction system that uses a combination of dissolved titanium hydroxide (in minute amounts) which forms an insoluble compound with the uranyl ion, and the insoluble compound then being sorbed out on activated carbon. Such a system showed partition coefficients in excess of 10 5 in fresh water. However, the system was not tested in seawater

  3. Seawater spray injury to Quercus acutissima leaves: crystal deposition, stomatal clogging, and chloroplast degeneration.

    Science.gov (United States)

    Kim, Ki Woo; Koo, Kyosang; Kim, Pan-Gi

    2011-05-01

    Effects of seawater spray on leaf structure were investigated in Quercus acutissima by electron microscopy and X-ray microanalysis. Two-year-old seedlings of Q. acutissima were sprayed with seawater and kept in a greenhouse maintained at 25°C. The most recognizable symptoms of seawater-sprayed seedlings included leaf necrosis, crystal deposition, stomatal clogging, and chloroplast degeneration. Field emission scanning electron microscopy revealed that the leaf surface was covered with additional layers of remnants of seawater spray. Composed of sodium and chloride, cube-shaped crystals (halite) were prevalently found on trichomes and epidermis, and formed aggregates. Meanwhile, wedge-shaped crystals were deposited on epidermis and consisted of calcium and sulfur. As a result of stomatal clogging by crystal deposition on the abaxial surface, it was conceivable that plant respiration became severely hampered. Transmission electron microscopy showed degenerated cytoplasm of seawater-sprayed leaves. It was common to observe severe plasmolysis and disrupted chloroplasts with a reduced number of thylakoids in grana. These results indicate that foliar applications of seawater were sufficient to induce necrosis of Q. acutissima seedlings as an abiotic disturbance factor. Copyright © 2010 Wiley-Liss, Inc.

  4. Bacterial biofilms utilization of low concentrations of organic matter on hydrophile surfaces submerged in seawater

    Directory of Open Access Journals (Sweden)

    Aurelia Manuela Moldoveanu

    2011-12-01

    Full Text Available A series of experiments were designed to determine the effect and the metabolic rate utilization of various types of organic matter in low concentration by heterotrophic marine bacteria using as Henrici slide technique as culture method and “in vitro” static conditions in sterile containers in order to obtain bacterial biofilms on the hydrophile surface of glass. The bacteria attachment and biofilm formation was analyzed for a period from 2 hours to 72 hours in order to observe de first phase of biofilm formation in condition of seawater supplied  with organic matter and noninvasive optic microscopy analysis. The utilization of five different  types of organic substances (amino-acid mixture, yeast extract, tryptone, glucose and starch reveled that bacteria multiply and are otherwise physiologically active in this very dilute nutrient solutions of 0.1% and also the results revealed that the bacterial growth was considerable in the case of the substances like amino-acid mixture with a total density of 30.9∙103 cells/mm2  and tryptone with a total density of 28.85∙103 cells/mm2  comparable to the other types of organic matter used to supply the seawater

  5. Control of DMSO in wastewater to prevent DMS nuisance odors.

    Science.gov (United States)

    Cheng, Xianhao; Wodarczyk, Michael; Lendzinski, Robert; Peterkin, Earl; Burlingame, Gary A

    2009-07-01

    A "canned corn-like" odor was periodically detected at Philadelphia's Northeast Water Pollution Control Plant (NEWPCP) for more than two decades. Previous research concluded that it was caused by dimethyl sulfide (DMS), from the reduction of dimethyl sulfoxide (DMSO) discharged by a local industrial customer. Several process modifications were implemented at the industrial site to eliminate the "canned corn-like" odor. Results showed that enhancing DMSO recovery by 25% and equalizing the aqueous wash discharge over a longer period of time reduced the DMSO source peak discharge from 1124 to 49 kg/h, and the peak concentrations of DMSO and DMS at the NEWPCP by 81 and 88%. Reduction of DMSO discharge by segregating the first wash for off-site disposal further reduced the peak discharge of DMSO from 49 to 18 kg/h at the source, and DMSO and DMS concentrations at the NEWPCP by 48 and 92%. Segregation of the dehydration distillate for off-site disposal reduced DMSO discharge by 3 kg/h. Modifications by concentrating a higher percentage of the DMSO into the first wash and increasing the DMSO solvent recovery by an additional 33% reduced the total DMSO discharge from 522 to 200 kg and peak discharge rate from 15 to 6 kg/h. All of these process modifications collectively reduced the DMSO source discharge by 92% and the DMSO concentration received at NEWPCP by 97%, from 12 mg/L to approximately 500 microg/L. At this reduced concentration, the company's wastewater discharge was no longer found to cause the "canned corn" odor at the fence line of NEWPCP, thereby mitigating any further need for odor control.

  6. Post-Mesozoic Rapid Increase of Seawater Mg/Ca due to Enhanced Mantle-Seawater Interaction

    Science.gov (United States)

    Ligi, Marco; Bonatti, Enrico; Cuffaro, Marco; Brunelli, Daniele

    2013-01-01

    The seawater Mg/Ca ratio increased significantly from ~ 80 Ma to present, as suggested by studies of carbonate veins in oceanic basalts and of fluid inclusions in halite. We show here that reactions of mantle-derived peridotites with seawater along slow spreading mid-ocean ridges contributed to the post-Cretaceous Mg/Ca increase. These reactions can release to modern seawater up to 20% of the yearly Mg river input. However, no significant peridotite-seawater interaction and Mg-release to the ocean occur in fast spreading, East Pacific Rise-type ridges. The Mesozoic Pangean superocean implies a hot fast spreading ridge system. This prevented peridotite-seawater interaction and Mg release to the Mesozoic ocean, but favored hydrothermal Mg capture and Ca release by the basaltic crust, resulting in a low seawater Mg/Ca ratio. Continent dispersal and development of slow spreading ridges allowed Mg release to the ocean by peridotite-seawater reactions, contributing to the increase of the Mg/Ca ratio of post-Mesozoic seawater. PMID:24067442

  7. The platinum (II) complex [Pt(O,O'-acac)(γ-acac)(DMS)] alters the intracellular calcium homeostasis in MCF-7 breast cancer cells.

    Science.gov (United States)

    Muscella, Antonella; Calabriso, Nadia; Vetrugno, Carla; Fanizzi, Francesco Paolo; De Pascali, Sandra Angelica; Storelli, Carlo; Marsigliante, Santo

    2011-01-01

    It was previously demonstrated that [Pt(O,O'-acac)(γ-acac)(DMS)] exerted toxic effects at high doses, whilst sub-cytotoxic concentrations induced anoikis and decreased cell migration. Aim of this study was to investigate the hypothesis that [Pt(O,O'-acac)(γ-acac)(DMS)] alters the [Ca(2+)](i) and that this is linked to its ability to trigger rapid apoptosis in MCF-7 cells. Thus, cells were treated with [Pt(O,O'-acac)(γ-acac)(DMS)] and its effects on some of the systems regulating Ca(2+) homeostasis were studied, also in cells dealing with the complex changes occurring during the Ca(2+) signalling evoked by extracellular stimuli. [Pt(O,O'-acac)(γ-acac)(DMS)] caused the decrease of PMCA activity (but not SERCA or SPCA) and Ca(2+) membrane permeability. These two opposite effects on [Ca(2+)](i) resulted in its overall increase from 102±12nM to 250±24nM after 15min incubation. The effects of [Pt(O,O'-acac)(γ-acac)(DMS)] were also evident when cells were stimulated with ATP: the changes in Ca(2+) levels caused by purinergic stimulation resulted altered due to decreased PMCA activity and to the closure of Ca(2+) channels opened by purinergic receptor. Conversely, [Pt(O,O'-acac)(γ-acac)(DMS)] did not affect the store-operated Ca(2+) channels opened by thapsigargin or by ATP. [Pt(O,O'-acac)(γ-acac)(DMS)] provoked the activation of PKC-α and the production of ROS that were responsible for the Ca(2+) permeability and PMCA activity decrease, respectively. The overall effect of [Pt(O,O'-acac)(γ-acac)(DMS)] is to increase the [Ca(2+)](i), an effect that is likely to be linked to its ability to trigger rapid apoptosis in MCF-7 cells. These data reinforce the notion that [Pt(O,O'-acac)(γ-acac)(DMS)] would be a promising drug in cancer treatment. Copyright © 2010 Elsevier Inc. All rights reserved.

  8. Nature/culture/seawater.

    Science.gov (United States)

    Helmreich, Stefan

    2011-01-01

    Seawater has occupied an ambiguous place in anthropological categories of "nature" and "culture." Seawater as nature appears as potentiality of form and uncontainable flux; it moves faster than culture - with culture frequently figured through land-based metaphors - even as culture seeks to channel water's (nature's) flow. Seawater as culture manifests as a medium of pleasure, sustenance, travel, disaster. I argue that, although seawater's qualities in early anthropology were portrayed impressionistically, today technical, scientific descriptions of water's form prevail. For example, processes of globalization - which may also be called "oceanization" - are often described as "currents," "flows," and "circulations." Examining sea-set ethnography, maritime anthropologies, and contemporary social theory, I propose that seawater has operated as a “theory machine” for generating insights about human cultural organization. I develop this argument with ethnography from the Sargasso Sea and in the Sea Islands. I conclude with a critique of appeals to water's form in social theory.

  9. Comparative toxicokinetics of MMB4 DMS in rats, rabbits, dogs, and monkeys following single and repeated intramuscular administration.

    Science.gov (United States)

    Hong, S Peter; Gibbs, Seth T; Kobs, Dean J; Hawk, Michael A; Croutch, Claire R; Osheroff, Merrill R; Johnson, Jerry D; Burback, Brian L

    2013-01-01

    1,1'-Methylenebis[4-[(hydroxyimino)methyl]-pyridinium] (MMB4) dimethanesulfonate (DMS) is a bisquaternary pyridinium aldoxime that reactivates acetylcholinesterase inhibited by organophosphorus nerve agent. Time courses of MMB4 concentrations in plasma were characterized following 7-day repeated intramuscular (IM) administrations of MMB4 DMS to male and female Sprague-Dawley rats, New Zealand White rabbits, beagle dogs (single dose only), and rhesus monkeys at drug dose levels used in earlier toxicology studies. In general, there were no significant differences in MMB4 toxicokinetic (TK) parameters between males and females for all the species tested in these studies. After a single IM administration to rats, rabbits, dogs, and monkeys, MMB4 DMS was rapidly absorbed, resulting in average T max values ranging from 5 to 30 minutes. Although C max values did not increase dose proportionally, the overall exposure to MMB4 in these preclinical species, as indicated by area under the curve (AUC) extrapolated to the infinity (AUC∞) values, increased in an approximately dose-proportional manner. The MMB4 DMS was extensively absorbed into the systemic circulation after IM administration as demonstrated by greater than 80% absolute bioavailability values for rats, rabbits, and dogs. Repeated administrations of MMB4 DMS for 7 days did not overtly alter TK parameters for MMB4 in rats, rabbits, and monkeys (150 and 300 mg/kg/d dose groups only). However, C max and AUC values decreased in monkeys given 450 and 600 mg/kg IM doses of MMB4 DMS following repeated administrations for 7 days. Based on the TK results obtained from the current study and published investigations, it was found that the apparent volume of distribution and clearance values were similar among various preclinical species, except for the rat.

  10. Materials resistant to seawater

    International Nuclear Information System (INIS)

    Lunde, L.

    1986-03-01

    The report is a summary of the topics discussed at a two-day seminar at Institute for Energy Technology, Kjeller in August 1985. Experience with seawater corrosion in Nordic power reactor plants was discussed. There was also input from Danish experience with seawater corrosion in coal fired power plants. The following topics were dealt with: Experience in seawater cooling system materials, chlorination of seawater systems, and accelerated laboratory tests for stainless steels

  11. 0-6686 : improving DMS 9210 requirements for limestone rock asphalt : [project summary].

    Science.gov (United States)

    2013-08-01

    Limestone rock asphalt (LRA) mixtures have : been produced and placed for several decades : using specification requirements currently listed : under DMS 9210, Limestone Rock Asphalt (LRA). : Several Texas Department of Transportation : (TxDOT) distr...

  12. Biomass production of Tetraselmis suecica using seawater with sanguaza

    Directory of Open Access Journals (Sweden)

    Juan Silva B.

    2011-03-01

    Full Text Available The growth of Tetraselmis suecica was evaluated. The experiment was realized using the Response Surface Methodology (RSM with Central Composite Rotational Design (CCRD with two factors, pH and sanguaza/seawater concentration in the range of 7 - 9 and 2 - 5 % (v/v, respectively. The culture media were stirred by bubbling air constantly (0.07 L/s and continuously illuminated with 40 W of fluorescent light in glass containers of 1.5 L capacity at a temperature of 22.5 ± 2.1 °C. Using the Gompertz mathematical model was determined that from an 8.0 of pH and a ratio of 3.5% of sanguaza/seawater, the Tetraselmis suecica achieves maximum growth. An 8.71 of pH and a ratio of 4.56% of sanguaza/seawater allow the Tetraselmis suecica maximum growth (logN/N0 of 0.659, with a 12.3% of prediction error by applying a mathematical model of 2nd order. According to the study, the values obtained in sanguaza/seawater as a culture medium outperformed the traditionally used culture medium (Guillard F/2 with seawater. The results demonstrate the potential use of the sanguaza/seawater medium in scalable studies on pilot scale production of Tetraselmis suecica, with a view to the production of biodiesel

  13. Global Cr-isotope distributions in surface seawater and incorporation of Cr isotopes into carbonate shells

    DEFF Research Database (Denmark)

    Paulukat, Cora Stefanie; Frei, Robert; Vögelin, Andrea Regula

    produced carbonate shells (bivalves, gastropods) and corals. Our preliminary data set ranges approximately from d53Cr = -0.2 to +0.7‰. They are isotopically lighter than local seawater. This is in good agreement with [6], who measured a negative offset from seawater in corals. These offsets indicate some...

  14. Formation pathways of DMSO(2) in the addition channel of the OH-initiated DMS oxidation: A theoretical study.

    Science.gov (United States)

    Ramírez-Anguita, Juan M; González-Lafont, Angels; Lluch, José M

    2009-07-15

    The production of dimethyl sulfoxide (DMSO) and dimethyl sulfone (DMSO(2)) in the dimethyl sulfide (DMS) degradation scheme initiated by the hydroxyl (OH) radical has been shown to be very sensitive to nitrogen oxides (NO(x)) levels. In the present work we have explored the potential energy surfaces corresponding to several reaction pathways which yield DMSO(2) from the CH(3)S(O)(OH)CH(3) adduct [including the formation of CH(3)S(O)(OH)CH(3) from the reaction of DMSO with OH] and the reaction channels that yield DMSO or/and DMSO(2) from the CH(3)S(O(2))(OH)CH(3) adduct are also studied. The formation of the CH(3)S(O(2))(OH)CH(3) adduct from CH(3)S(OH)CH(3) (DMS-OH) and O(2) was analyzed in our previous work. All these pathways due to the presence of NO(x) (NO and NO(2)) and also due to the reactions with O(2), OH and HO(2) are compared with the objective of inferring their kinetic relevance in the laboratory experiments that measure DMSO(2) (and DMSO) formation yields. In particular, our theoretical results clearly show the existence of NO(x)-dependent pathways leading to the formation of DMSO(2), which could explain some of these experimental results in comparison with experimental measurements carried out in NO(x)-free conditions. Our results indicate that the relative importance of the addition channel in the DMS oxidation process can be dependent on the NO(x) content of chamber experiments and of atmospheric conditions. (c) 2008 Wiley Periodicals, Inc.

  15. Antitumour and antiangiogenic activities of [Pt(O,O'-acac)(γ-acac)(DMS)] in a xenograft model of human renal cell carcinoma.

    Science.gov (United States)

    Muscella, A; Vetrugno, C; Biagioni, F; Calabriso, N; Calierno, M T; Fornai, F; De Pascali, S A; Marsigliante, S; Fanizzi, F P

    2016-09-01

    It is thought that the mechanism of action of anticancer chemotherapeutic agents is mainly due to a direct inhibition of tumour cell proliferation. In tumour specimens, the endothelial cell proliferation rate increases, suggesting that the therapeutic effects of anticancer agents could also be attributed to inhibition of tumour angiogenesis. Hence, we investigated the potential effects of [Pt(O,O'-acac)(γ-acac)(DMS)] ([Pt(DMS)]), a new platinum drug for non-genomic targets, on human renal carcinoma and compared them with those of the well-established anticancer drug, cisplatin. Tumour growth, tumour cell proliferation and microvessel density were investigated in a xenograft model of renal cell carcinoma, developed by injecting Caki-1 cells into BALB/c nude mice. The antiangiogenic potential of compounds was also investigated using HUVECs. Treatment of the Caki-1 cells with cisplatin or [Pt(DMS)] resulted in a dose-dependent inhibition of cell survival, but the cytotoxicity of [Pt(DMS)] was approximately fivefold greater than that of cisplatin. [Pt(DMS)] was much more effective than cisplatin at inhibiting tumour growth, proliferation and angiogenesis in vivo, as well as migration, tube formation and MMP1, MMP2 and MMP9 secretion of endothelial cells in vitro. Whereas, cisplatin exerted a greater cytotoxic effect on HUVECs, but did not affect tube formation or the migration of endothelial cells. In addition, treatment of the xenograft mice with [Pt(DMS)] decreased VEGF, MMP1 and MMP2 expressions in tumours. The antiangiogenic and antitumour activities of [Pt(DMS)] provide a solid starting point for its validation as a suitable candidate for further pharmacological testing. © 2016 The British Pharmacological Society.

  16. Different apoptotic effects of [Pt(O,O'-acac)(γ-acac)(DMS)] and cisplatin on normal and cancerous human epithelial breast cells in primary culture.

    Science.gov (United States)

    Vetrugno, Carla; Muscella, Antonella; Fanizzi, Francesco Paolo; Cossa, Luca Giulio; Migoni, Danilo; De Pascali, Sandra Angelica; Marsigliante, Santo

    2014-11-01

    The aim of this study was to determine whether [platinum (Pt)(O,O'-acetylacetonate (acac))(γ-acac)(dimethylsulphide (DMS))] is differentially cytotoxic in normal and cancer cells, and to measure comparative levels of cytotoxicity compared with cisplatin in the same cells. We performed experiments on cancerous and normal epithelial breast cells in primary culture obtained from the same patients. The apoptotic effects [Pt(O,O'-acac)(γ-acac)(DMS)] and cisplatin in cancerous and normal breast cells were compared. Cancer cells were more sensitive to [Pt(O,O'-acac)(γ-acac)(DMS)] (IC50 = 5.22 ± 1.2 μmol·L(-1)) than normal cells (IC50 = 116.9 ± 8.8 μmol·L(-1)). However, the difference was less strong when cisplatin was used (IC50 = 96.0 ± 6.9 and 61.9 ± 6.1 μmol·L(-1) for cancer and normal cells respectively). Both compounds caused reactive oxygen species (ROS) production with different mechanisms: [Pt(O,O'-acac)(γ-acac)(DMS)] quickly activated NAD(P)H oxidase while cisplatin caused a slower formation of mitochondrial ROS. Cisplatin and [Pt(O,O'-acac)(γ-acac)(DMS)] caused activation of caspases, proteolysis of PARP and modulation of Bcl-2, Bax and Bid. [Pt(O,O'-acac)(γ-acac)(DMS)] also caused leakage of cytochrome c from the mitochondria. Overall, these processes proceeded more quickly in cells treated with [Pt(O,O'-acac)(γ-acac)(DMS)] compared with cisplatin. [Pt(O,O'-acac)(γ-acac)(DMS)] effects were faster and quantitatively greater in cancer than in normal cells. [Pt(O,O'-acac)(γ-acac)(DMS)] caused a fast decrease of mitochondrial membrane potential, especially in cancer cells. [Pt(O,O'-acac)(γ-acac)(DMS)] was specific to breast cancer cells in primary culture, and this observation makes this compound potentially more interesting than cisplatin. © 2014 The British Pharmacological Society.

  17. Different apoptotic effects of [Pt(O,O′-acac)(γ-acac)(DMS)] and cisplatin on normal and cancerous human epithelial breast cells in primary culture

    Science.gov (United States)

    Vetrugno, Carla; Muscella, Antonella; Fanizzi, Francesco Paolo; Cossa, Luca Giulio; Migoni, Danilo; De Pascali, Sandra Angelica; Marsigliante, Santo

    2014-01-01

    Background and Purpose The aim of this study was to determine whether [platinum (Pt)(O,O′-acetylacetonate (acac))(γ-acac)(dimethylsulphide (DMS))] is differentially cytotoxic in normal and cancer cells, and to measure comparative levels of cytotoxicity compared with cisplatin in the same cells. Experimental Approach We performed experiments on cancerous and normal epithelial breast cells in primary culture obtained from the same patients. The apoptotic effects [Pt(O,O′-acac)(γ-acac)(DMS)] and cisplatin in cancerous and normal breast cells were compared. Key Results Cancer cells were more sensitive to [Pt(O,O′-acac)(γ-acac)(DMS)] (IC50 = 5.22 ± 1.2 μmol·L−1) than normal cells (IC50 = 116.9 ± 8.8 μmol·L−1). However, the difference was less strong when cisplatin was used (IC50 = 96.0 ± 6.9 and 61.9 ± 6.1 μmol·L−1 for cancer and normal cells respectively). Both compounds caused reactive oxygen species (ROS) production with different mechanisms: [Pt(O,O′-acac)(γ-acac)(DMS)] quickly activated NAD(P)H oxidase while cisplatin caused a slower formation of mitochondrial ROS. Cisplatin and [Pt(O,O′-acac)(γ-acac)(DMS)] caused activation of caspases, proteolysis of PARP and modulation of Bcl-2, Bax and Bid. [Pt(O,O′-acac)(γ-acac)(DMS)] also caused leakage of cytochrome c from the mitochondria. Overall, these processes proceeded more quickly in cells treated with [Pt(O,O′-acac)(γ-acac)(DMS)] compared with cisplatin. [Pt(O,O′-acac)(γ-acac)(DMS)] effects were faster and quantitatively greater in cancer than in normal cells. [Pt(O,O′-acac)(γ-acac)(DMS)] caused a fast decrease of mitochondrial membrane potential, especially in cancer cells. Conclusions and Implications [Pt(O,O′-acac)(γ-acac)(DMS)] was specific to breast cancer cells in primary culture, and this observation makes this compound potentially more interesting than cisplatin. PMID:24990093

  18. Guidelines for Implementing Advanced Distribution Management Systems-Requirements for DMS Integration with DERMS and Microgrids

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jianhui [Argonne National Lab. (ANL), Argonne, IL (United States); Chen, Chen [Argonne National Lab. (ANL), Argonne, IL (United States); Lu, Xiaonan [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-08-01

    This guideline focuses on the integration of DMS with DERMS and microgrids connected to the distribution grid by defining generic and fundamental design and implementation principles and strategies. It starts by addressing the current status, objectives, and core functionalities of each system, and then discusses the new challenges and the common principles of DMS design and implementation for integration with DERMS and microgrids to realize enhanced grid operation reliability and quality power delivery to consumers while also achieving the maximum energy economics from the DER and microgrid connections.

  19. Butterfly valves for seawater

    International Nuclear Information System (INIS)

    Yamanaka, Katsuto

    1991-01-01

    Recently in thermal and nuclear power stations and chemical plants which have become large capacity, large quantity of cooling water is required, and mostly seawater is utilized. In these cooling water systems, considering thermal efficiency and economy, the pipings become complex, and various control functions are demanded. For the purpose, the installation of shut-off valves and control valves for pipings is necessary. The various types of valves have been employed, and in particular, butterfly valves have many merits in their function, size, structure, operation, maintenance, usable period, price and so on. The corrosion behavior of seawater is complicated due to the pollution of seawater, therefore, the environment of the valves used for seawater became severe. The structure and the features of the butterfly valves for seawater, the change of the structure of the butterfly valves for seawater and the checkup of the butterfly valves for seawater are reported. The corrosion of metallic materials is complicatedly different due to the locating condition of plants, the state of pipings and the condition of use. The corrosion countermeasures for butterfly valves must be examined from the synthetic viewpoints. (K.I.)

  20. Nucleation from seawater emissions during mesocosm experiments

    Science.gov (United States)

    Rose, Clémence; Culot, Anais; Pey, Jorge; Schwier, Allison; Mas, Sébastien; Charriere, Bruno; Sempéré, Richard; Marchand, Nicolas; D'Anna, Barbara; Sellegri, Karine

    2015-04-01

    Nucleation and new particle formation in the marine atmosphere is usually associated to the presence of macroalgea emerged at low tides in coastal areas, while these processes were very rarely detected away from coastlines. In the present study, we evidence the formation of new particles from the 1 nm size above the seawater surface in the absence of any macroalgea population. Within the SAM project (Sources of marine Aerosol in the Mediterranean),seawater mesocosms experiments were deployed in May 2013 at the STARESO in western Corsica, with the goal of investigating the relationship between marine aerosol emissions and the seawater biogeochemical properties. Three mesocosms imprisoned 3,3 m3 of seawater each and their emerged part was flushed with aerosol-filtered natural air. One of these mesocosms was left unchanged as control and the two others were enriched by addition of nitrates and phosphates respecting Redfield ratio (N:P = 16) in order to create different levels of phytoplanctonic activities. We followed both water and air characteristics of three mesocosms during a period of three weeks by using online water and atmospheric probes as well as seawater daily samples for chemical and biological analysis. Secondary new particle formation was followed on-line in the emerged parts of the mesocosms, using a SMPS for the size distribution above 6 nm and a Particle Size Magnifyer (PSM) for the number of cluster particles between 1 and 6 nm. We will present how the cluster formation rates and early growth rates relate to the gaz-phase emissions from the seawater and to its biogeochemical properties. Aknowledgemnts: The authors want to acknowledge the financial support of the ANR "Source of marine Aerosol in the Mediterranean" (SAM), and the support of MISTRAL CHARMEX and MERMEX programs.

  1. Improving DMS 9210 requirements for limestone rock asphalt : year one interim report.

    Science.gov (United States)

    2013-05-01

    Limestone Rock Asphalt (LRA) mixtures have been produced and placed for several decades using specification requirements currently listed under DMS 9210. Several Districts have had placement issues and premature failures at the beginning of 2010. The...

  2. Ultra-trace plutonium determination in small volume seawater by sector field inductively coupled plasma mass spectrometry with application to Fukushima seawater samples.

    Science.gov (United States)

    Bu, Wenting; Zheng, Jian; Guo, Qiuju; Aono, Tatsuo; Tagami, Keiko; Uchida, Shigeo; Tazoe, Hirofumi; Yamada, Masatoshi

    2014-04-11

    Long-term monitoring of Pu isotopes in seawater is required for assessing Pu contamination in the marine environment from the Fukushima Dai-ichi Nuclear Power Plant accident. In this study, we established an accurate and precise analytical method based on anion-exchange chromatography and SF-ICP-MS. This method was able to determine Pu isotopes in seawater samples with small volumes (20-60L). The U decontamination factor was 3×10(7)-1×10(8), which provided sufficient removal of interfering U from the seawater samples. The estimated limits of detection for (239)Pu and (240)Pu were 0.11fgmL(-1) and 0.08fgmL(-1), respectively, which corresponded to 0.01mBqm(-3) for (239)Pu and 0.03mBqm(-3) for (240)Pu when a 20L volume of seawater was measured. We achieved good precision (2.9%) and accuracy (0.8%) for measurement of the (240)Pu/(239)Pu atom ratio in the standard Pu solution with a (239)Pu concentration of 11fgmL(-1) and (240)Pu concentration of 2.7fgmL(-1). Seawater reference materials were used for the method validation and both the (239+240)Pu activities and (240)Pu/(239)Pu atom ratios agreed well with the expected values. Surface and bottom seawater samples collected off Fukushima in the western North Pacific since March 2011 were analyzed. Our results suggested that there was no significant variation of the Pu distribution in seawater in the investigated areas compared to the distribution before the accident. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Plutonium determination in seawater by inductively coupled plasma mass spectrometry: A review.

    Science.gov (United States)

    Cao, Liguo; Bu, Wenting; Zheng, Jian; Pan, Shaoming; Wang, Zhongtang; Uchida, Shigeo

    2016-05-01

    Knowing the concentration and isotopic ratio of Pu in seawater is of critical importance for assessing Pu contamination and investigating oceanic processes. In recent decades, the concentration of (239+240)Pu in seawater, particularly for surface seawater, has presented an exponential decreasing trend with time; thus determination of Pu in seawater has become a challenge nowadays. Here, we have summarized and critically discussed a variety of reported analytical methods for Pu determination in seawater sample based on inductively coupled plasma mass spectrometry (ICP-MS) analytical technique for rapid ultra-trace detection of Pu. Generally, pretreatments for seawater sample include co-precipitation, valence adjustment and chemical separation and purification procedures, all of which are comprehensively reviewed. Overall, the selected anion-exchange, extraction resins and operation condition are important for decontamination of interference from matrix elements and achieving satisfactory chemical yields. In addition, other mass spectrometric and radiometric detections are briefly addressed and compared with the focus on assessing ICP-MS. Finally, we discuss some issues and prospects in determination and application of Pu isotopes in seawater samples for future research. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Analysis of selected antibiotics in surface freshwater and seawater using direct injection in liquid chromatography electrospray ionization tandem mass spectrometry.

    Science.gov (United States)

    Bayen, Stéphane; Yi, Xinzhu; Segovia, Elvagris; Zhou, Zhi; Kelly, Barry C

    2014-04-18

    Emerging contaminants such as antibiotics have received recent attention as they have been detected in natural waters and health concerns over potential antibiotic resistance. With the purpose to investigate fast and high-throughput analysis, and eventually the continuous on-line analysis of emerging contaminants, this study presents results on the analysis of seven selected antibiotics (sulfadiazine, sulfamethazine, sulfamerazine, sulfamethoxazole, chloramphenicol, lincomycin, tylosin) in surface freshwater and seawater using direct injection of a small sample volume (20μL) in liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). Notably, direct injection of seawater in the LC-ESI-MS/MS was made possible on account of the post-column switch on the system, which allows diversion of salt-containing solutions flushed out of the column to the waste. Mean recoveries based on the isotope dilution method average 95±14% and 96±28% amongst the compounds for spiked freshwater and seawater, respectively. Linearity across six spiking levels was assessed and the response was linear (r(2)>0.99) for all compounds. Direct injection concentrations were compared for real samples to those obtained with the conventional SPE-based analysis and both techniques concurs on the presence/absence and levels of the compounds in real samples. These results suggest direct injection is a reliable method to detect antibiotics in both freshwater and seawater. Method detection limits for the direct injection technique (37pg/L to 226ng/L in freshwater, and from 16pg/to 26ng/L in seawater) are sufficient for a number of environmental applications, for example the fast screening of water samples for ecological risk assessments. In the present study of real samples, this new method allowed for example the positive detection of some compounds (e.g. lincomycin) down to the sub ng/L range. The direct injection method appears to be relatively cheaper and faster

  5. Seasonal levels of the Vibrio predator Bacteriovorax in Atlantic, Pacific and Gulf Coast Seawater

    Science.gov (United States)

    Bacteriovorax were quantified in US Atlantic, Gulf and Pacific seawater to determine baseline levels of these predatory bacteria and possible seasonal fluctuations in levels. Surface seawater was analyzed monthly for 1 year from Kailua-Kona, Hawaii; the Gulf Coast of Alabama; and four sites along t...

  6. Coupled sea surface temperature-seawater delta O-18 reconstructions in the Arabian Sea at the millennial scale for the last 35 ka

    NARCIS (Netherlands)

    Anand, P.; Kroon, D.; Singh, A.D.; Ganssen, G.M.

    2008-01-01

    Two sediment cores from the western (905; 10.46°9′N, 51.56°4′E, water depth 1586 m) and eastern (SK17; 15°15′N, 72°58′E, water depth 840 m) Arabian Sea were used to study past sea surface temperatures (SST) and seawater δ

  7. DMS triggers apoptosis associated with the inhibition of SPHK1/NF-κB activation and increase in intracellular Ca2+ concentration in human cancer cells.

    Science.gov (United States)

    Chen, Kan; Pan, Qiuwei; Gao, Ying; Yang, Xinyan; Wang, Shibing; Peppelenbosch, Maikel P; Kong, Xiangdong

    2014-01-01

    N,N-Dimethyl-D-erythro-sphingosine (DMS) is known to induce cell apoptosis by specifically inhibiting sphingosine kinase 1 (SPHK1) and modulating the activity of cellular ceramide levels. The present study investigated the effects and the mechanism(s) of action of DMS in human lung cancer cells. We found that DMS dose-dependently suppressed cell proliferation and induced cell apoptosis in the human lung cancer cell line, A549. Mechanistically, treatment with DMS suppressed the activation of SPHK1 and nuclear factor-κB (NF-κB) p65, but increased intracellular [Ca2+]i in A549 cells. This study demonstrates that DMS triggers the apoptosis of human lung cancer cells through the modulation of SPHK1, NF-κB and calcium signaling. These molecules may represent targets for anticancer drug design.

  8. Development of Alloy Coating Process of Steel Pipe for Seawater service

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jong Man; Kwon, Taeg Kyu; Lee, Sang Hyeog [Daewoo Shipbuilding and Marine Engineering Co., Ltd., Okpo (Korea)

    2001-02-01

    The new alloy coating process was developed to apply steel pipe for seawater service. This process consists of Zn-Al hot-dip coating treatment immediately following after normal galvanizing treatment. The alloy coating process formed double layer after surface treatment, and the surface layer was similar to that of Galfan steel and the intermetallic layer was also similar to that of aluminized steel. The alloy coating layer protect steel pipe galvanically and provide steel pipe with high resistance to general corrosion of seawater. This new alloy coated steel pipe had also good weldability and adhesion strength of paints compared to galvanized steel. 5 refs., 14 figs.

  9. Dental Management Survey Brazil (DMS-BR): creation and validation of a management instrument

    Science.gov (United States)

    Gonzales, Paola Sampaio; Martins, Ismar Eduardo; Biazevic, Maria Gabriela Haye; Silva, Paulo Roberto da; Michel-Crosato, Edgard

    2017-04-10

    Questionnaires for the assessment of knowledge and self-perception can be useful to diagnose what a dentist knows about management and administration. The aim of the present study was to create and validate the Dental Management Survey Brazil (DMS-BR) scale, based on meetings with experts in the field. After having elaborated the first version, 10 audits were performed in dental offices in order to produce the final version, which included nine dimensions: location, patient, finance, marketing, competition, quality, staff, career, and productivity. The accuracy of the instrument was measured by intrarater and interrater reliability. In the validation phase, 247 Brazilian dentists answered a web-based questionnaire. The data were processed using Stata 13.0 and the significance level was set at 95%. The instrument had intrarater and interrater reliability (ICC-0.93 and 0.94). The overall average of respondents for the DMS-BR scale was 3.77 (SD = 0.45). Skewness and kurtosis were below absolute values 3 and 7, respectively. Internal validity measured by Cronbach's alpha was 0.925 and the correlation of each dimension with the final result of the DMS-BR ranged between 0.606 and 0.810. Correlation with the job satisfaction scale was 0.661. The SEM data ranged between 0.80 and 0.56. The questionnaire presented satisfactory indicators of dentists' self-perception about management and administration activities.

  10. Post-Mesozoic Rapid Increase of Seawater Mg/Ca due to Enhanced Mantle-Seawater Interaction

    OpenAIRE

    Marco Ligi; Enrico Bonatti; Marco Cuffaro; Daniele Brunelli

    2013-01-01

    The seawater Mg/Ca ratio increased significantly from ~ 80?Ma to present, as suggested by studies of carbonate veins in oceanic basalts and of fluid inclusions in halite. We show here that reactions of mantle-derived peridotites with seawater along slow spreading mid-ocean ridges contributed to the post-Cretaceous Mg/Ca increase. These reactions can release to modern seawater up to 20% of the yearly Mg river input. However, no significant peridotite-seawater interaction and Mg-release to the ...

  11. epiDMS: Data Management and Analytics for Decision-Making From Epidemic Spread Simulation Ensembles.

    Science.gov (United States)

    Liu, Sicong; Poccia, Silvestro; Candan, K Selçuk; Chowell, Gerardo; Sapino, Maria Luisa

    2016-12-01

    Carefully calibrated large-scale computational models of epidemic spread represent a powerful tool to support the decision-making process during epidemic emergencies. Epidemic models are being increasingly used for generating forecasts of the spatial-temporal progression of epidemics at different spatial scales and for assessing the likely impact of different intervention strategies. However, the management and analysis of simulation ensembles stemming from large-scale computational models pose challenges, particularly when dealing with multiple interdependent parameters, spanning multiple layers and geospatial frames, affected by complex dynamic processes operating at different resolutions. We describe and illustrate with examples a novel epidemic simulation data management system, epiDMS, that was developed to address the challenges that arise from the need to generate, search, visualize, and analyze, in a scalable manner, large volumes of epidemic simulation ensembles and observations during the progression of an epidemic. epiDMS is a publicly available system that facilitates management and analysis of large epidemic simulation ensembles. epiDMS aims to fill an important hole in decision-making during healthcare emergencies by enabling critical services with significant economic and health impact. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

  12. Processing of high-molecular-weight form adrenocorticotropin in human adrenocorticotropin-secreting tumor cell line (DMS-79) after transfection of prohormone convertase 1/3 gene.

    Science.gov (United States)

    Tateno, T; Kato, M; Tani, Y; Yoshimoto, T; Oki, Y; Hirata, Y

    2010-02-01

    Ectopic ACTH-producing tumors preferentially secrete biologically inactive ACTH precursors and ACTH-related fragments. DMS-79 is known to secrete unprocessed high-molecular-weight (HMW) form ACTH. To determine whether prohormone convertase (PC) 1/3 is involved in the abnormal processing of proopiomelanocortin (POMC), we studied whether PC1/3 and 2 genes are expressed in DMS-79, and whether overexpression of PC1/3 gene affects POMC processing pattern. Steady-state mRNA levels of PC1/3 and 2 were determined by real-time RT-PCR. Molecular weights of ACTH-related peptides were determined by chromatographical analyses coupled with ACTH and beta-endorphin (beta-END) radioimmunoassays. PC1/3 gene was transfected into DMS-79 by retrovirus transduction using pMX-IP vector encoding PC1/3 cDNA. The steady-state mRNA levels of PC1/3 and 2 in DMS-79 were lower than those in ACTH-secreting and nonfunctioning pituitary tumors. DMS-79 predominantly secreted HMW form with both ACTH and beta-END immunoreactivities by size-exclusion chromatography. After purification by immunoaffinity chromatography with anti-ACTH antibody, the apparent molecular weight of HMW form ACTH was estimated to be 16 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis with silver staining. After retroviral transfection of PC1/3 cDNA into DMS-79 and puromycin selection, PC1/3 stably-expressing cell line (DMS-79T) secreted two immunoreactive ACTH components, a major one coeluting with ACTH(1-39) and a minor one as a HMW form as well as two beta- END immunoreactive components coeluting with beta-lipotropic hormone and beta-END, respectively. Thus, we have established PC1/3 stably-expressing cell line (DMS-79T) capable of proteolytically processing ACTH precursor molecule(s) into mature ACTH and beta-END.

  13. Temperature profile data from surface seawater intake, bucket, and XBT casts in a world wide distribution from 1995-02-24 to 1996-06-23 (NODC Accession 9700060)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected using surface seawater intake, bucket, and XBT casts from several vessels in a world wide distribution from February 24,...

  14. Temperature profile data from surface seawater intake, bucket, and XBT casts in a world wide distribution from 1996-09-30 to 1997-05-27 (NODC Accession 9700161)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected using surface seawater intake, bucket, and XBT casts from several vessels in a world wide distribution from September 30,...

  15. Temperature profile data from surface seawater intake, bucket, and XBT casts in a world wide distribution from 1996-09-19 to 1997-03-25 (NODC Accession 9700061)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected using surface seawater intake, bucket, and XBT casts from several vessels in a world wide distribution from September 19,...

  16. Antitumour and antiangiogenic activities of [Pt(O,O′‐acac)(γ‐acac)(DMS)] in a xenograft model of human renal cell carcinoma

    Science.gov (United States)

    Vetrugno, C; Biagioni, F; Calabriso, N; Calierno, M T; Fornai, F; De Pascali, S A; Marsigliante, S; Fanizzi, F P

    2016-01-01

    Background and Purpose It is thought that the mechanism of action of anticancer chemotherapeutic agents is mainly due to a direct inhibition of tumour cell proliferation. In tumour specimens, the endothelial cell proliferation rate increases, suggesting that the therapeutic effects of anticancer agents could also be attributed to inhibition of tumour angiogenesis. Hence, we investigated the potential effects of [Pt(O,O′‐acac)(γ‐acac)(DMS)] ([Pt(DMS)]), a new platinum drug for non‐genomic targets, on human renal carcinoma and compared them with those of the well‐established anticancer drug, cisplatin. Experimental Approach Tumour growth, tumour cell proliferation and microvessel density were investigated in a xenograft model of renal cell carcinoma, developed by injecting Caki‐1 cells into BALB/c nude mice. The antiangiogenic potential of compounds was also investigated using HUVECs. Key Results Treatment of the Caki‐1 cells with cisplatin or [Pt(DMS)] resulted in a dose‐dependent inhibition of cell survival, but the cytotoxicity of [Pt(DMS)] was approximately fivefold greater than that of cisplatin. [Pt(DMS)] was much more effective than cisplatin at inhibiting tumour growth, proliferation and angiogenesis in vivo, as well as migration, tube formation and MMP1, MMP2 and MMP9 secretion of endothelial cells in vitro. Whereas, cisplatin exerted a greater cytotoxic effect on HUVECs, but did not affect tube formation or the migration of endothelial cells. In addition, treatment of the xenograft mice with [Pt(DMS)] decreased VEGF, MMP1 and MMP2 expressions in tumours. Conclusions and Implications The antiangiogenic and antitumour activities of [Pt(DMS)] provide a solid starting point for its validation as a suitable candidate for further pharmacological testing. PMID:27351124

  17. Structure-activity relationships of dimethylsphingosine (DMS) derivatives and their effects on intracellular pH and Ca2+ in the U937 monocyte cell line.

    Science.gov (United States)

    Chang, Young-Ja; Lee, Yun-Kyung; Lee, Eun-Hee; Park, Jeong-Ju; Chung, Sung-Kee; Im, Dong-Soon

    2006-08-01

    We recently reported that dimethylsphingosine (DMS), a metabolite of sphingolipids, increased intracellular pH and Ca2+ concentration in U937 human monocytes. In the present study, we found that dimethylphytosphingosine (DMPH) induced the above responses more robustly than DMS. However, phytosphingosine, monomethylphytosphingosine or trimethylsphingosine showed little or no activity. Synthetic C3 deoxy analogues of sphingosine did show similar activities, with the C16 analogue more so than C18. The following structure-activity relationships were observed between DMS derivatives and the intracellular pH and Ca2+ concentrations in U937 monocytes; 1) dimethyl modification is important for the DMS-induced increase of intracellular pH and Ca2+, 2) the addition of an OH group on C4 enhances both activities, 3) the deletion of the OH group on C3 has a negligible effect on the activities, and 4) C16 appears to be more effective than C18. We also found that W-7, a calmodulin inhibitor, blocked the DMS-induced pH increase, whereas, KN-62, ML9, and MMPX, specific inhibitors for calmodulin-dependent kinase II, myosin light chain kinase, and Ca(2+)-calmodulin-dependent phosphodiesterase, respectively, did not affect DMS-induced increases of pH in the U937 monocytes.

  18. Temperature profile data from bucket, surface seawater intake, and XBT casts in a world wide distribution from 07 December 1995 to 18 October 1996 (NODC Accession 9600167)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected using bucket, surface seawater intake, and XBT casts from several vessels in a world wide distribution from December 07, 1995...

  19. Methanethiol Concentrations and Sea-Air Fluxes in the Subarctic NE Pacific Ocean

    Science.gov (United States)

    Kiene, R. P.; Williams, T. E.; Esson, K.; Tortell, P. D.; Dacey, J. W. H.

    2017-12-01

    Exchange of volatile organic sulfur from the ocean to the atmosphere impacts the global sulfur cycle and the climate system and is thought to occur mainly via the gas dimethylsulfide (DMS). DMS is produced during degradation of the abundant phytoplankton osmolyte dimethylsulfoniopropionate (DMSP) but bacteria can also convert dissolved DMSP into the sulfur gas methanethiol (MeSH). MeSH has been difficult to measure in seawater because of its high chemical and biological reactivity and, thus, information on MeSH concentrations, distribution and sea-air fluxes is limited. We measured MeSH in the northeast subarctic Pacific Ocean in July 2016, along transects with strong phytoplankton abundance gradients. Water samples obtained with Niskin bottles were analyzed for MeSH by purge-and-trap gas chromatography. Depth profiles showed that MeSH concentrations were high near the surface and declined with depth. Surface waters (5 m depth) had an average MeSH concentration of 0.75 nM with concentrations reaching up to 3nM. MeSH concentrations were correlated (r = 0.47) with microbial turnover of dissolved DMSP which ranged up to 236 nM per day. MeSH was also correlated with total DMSP (r = 0.93) and dissolved DMS (r = 0.63), supporting the conclusion that DMSP was a major precursor of MeSH. Surface water MeSH:DMS concentration ratios averaged 0.19 and ranged up to 0.50 indicating that MeSH was a significant fraction of the volatile sulfur pool in surface waters. Sea-air fluxes of MeSH averaged 15% of the combined DMS+MeSH flux, therefore MeSH contributed an important fraction of the sulfur emitted to the atmosphere from the subarctic NE Pacific Ocean.

  20. Transcriptome Analysis for Abnormal Spike Development of the Wheat Mutant dms.

    Science.gov (United States)

    Zhu, Xin-Xin; Li, Qiao-Yun; Shen, Chun-Cai; Duan, Zong-Biao; Yu, Dong-Yan; Niu, Ji-Shan; Ni, Yong-Jing; Jiang, Yu-Mei

    2016-01-01

    Wheat (Triticum aestivum L.) spike development is the foundation for grain yield. We obtained a novel wheat mutant, dms, characterized as dwarf, multi-pistil and sterility. Although the genetic changes are not clear, the heredity of traits suggests that a recessive gene locus controls the two traits of multi-pistil and sterility in self-pollinating populations of the medium plants (M), such that the dwarf genotype (D) and tall genotype (T) in the progeny of the mutant are ideal lines for studies regarding wheat spike development. The objective of this study was to explore the molecular basis for spike abnormalities of dwarf genotype. Four unigene libraries were assembled by sequencing the mRNAs of the super-bulked differentiating spikes and stem tips of the D and T plants. Using integrative analysis, we identified 419 genes highly expressed in spikes, including nine typical homeotic genes of the MADS-box family and the genes TaAP2, TaFL and TaDL. We also identified 143 genes that were significantly different between young spikes of T and D, and 26 genes that were putatively involved in spike differentiation. The result showed that the expression levels of TaAP1-2, TaAP2, and other genes involved in the majority of biological processes such as transcription, translation, cell division, photosynthesis, carbohydrate transport and metabolism, and energy production and conversion were significantly lower in D than in T. We identified a set of genes related to wheat floral organ differentiation, including typical homeotic genes. Our results showed that the major causal factors resulting in the spike abnormalities of dms were the lower expression homeotic genes, hormonal imbalance, repressed biological processes, and deficiency of construction materials and energy. We performed a series of studies on the homeotic genes, however the other three causal factors for spike abnormal phenotype of dms need further study.

  1. Flux patterns and membrane fouling propensity during desalination of seawater by forward osmosis

    KAUST Repository

    Li, Zhenyu; Yangali-Quintanilla, Victor; Valladares Linares, Rodrigo; Li, Qingyu; Zhan, Tong; Amy, Gary L.

    2012-01-01

    The membrane fouling propensity of natural seawater during forward osmosis was studied. Seawater from the Red Sea was used as the feed in a forward osmosis process while a 2. M sodium chloride solution was used as the draw solution. The process was conducted in a semi-batch mode under two crossflow velocities, 16.7. cm/s and 4.2. cm/s. For the first time reported, silica scaling was found to be the dominant inorganic fouling (scaling) on the surface of membrane active layer during seawater forward osmosis. Polymerization of dissolved silica was the major mechanism for the formation of silica scaling. After ten batches of seawater forward osmosis, the membrane surface was covered by a fouling layer of assorted polymerized silica clusters and natural organic matter, especially biopolymers. Moreover, the absorbed biopolymers also provided bacterial attachment sites. The accumulated organic fouling could be partially removed by water flushing while the polymerized silica was difficult to remove. The rate of flux decline was about 53% with a crossflow velocity of 16.7. cm/s while reaching more than 70% with a crossflow velocity of 4.2. cm/s. Both concentration polarization and fouling played roles in the decrease of flux. The salt rejection was stable at about 98% during seawater forward osmosis. In addition, an almost complete rejection of natural organic matter was attained. The results from this study are valuable for the design and development of a successful protocol for a pretreatment process before seawater forward osmosis and a cleaning method for fouled membranes. © 2011 Elsevier Ltd.

  2. Comparison of techniques for pre-concentrating radium from seawater

    International Nuclear Information System (INIS)

    Bourquin, M.; Van Beek, P.; Souhaut, M.; Jeandel, C.; Reyss, J.L.; Charette, M.A.

    2008-01-01

    In the framework of the KEOPS project (Kerguelen: compared study of the Ocean and the Plateau in Surface water), we aimed to provide information on the water mass pathways and vertical mixing on the Kerguelen Plateau, Southern Ocean, based on 228 Ra profiles. Because 228 Ra activities are extremely low in this area (∼ 0.1 dpm/100 kg or ∼ 2.10 -18 g kg -1 ), the filtration of large volumes of seawater was required in order to be able to detect it with minimal uncertainty. This challenging study was an opportunity for us to test and compare methods aimed at removing efficiently radium isotopes from seawater. We used Mn-fiber that retains radium and that allows the measurement of all four radium isotopes ( 226 Ra, 228 Ra, 223 Ra, 224 Ra). First, we used Niskin bottles or the ship's seawater intake to collect large volumes of seawater that were passed onto Mn-fiber in the laboratory. Second, we filled cartridges with Mn-fiber that we placed in tandem on in situ pumps. Finally, we fixed nylon nets filled with Mn-fiber on the frame of in situ pumps to allow the passive filtration of seawater during the pump deployment. Yields of radium fixation on the cartridges filled with Mn-fiber and placed on in situ pumps are ca. 30% when combining the two cartridges. Because large volumes of seawater can be filtered with these pumps, this yields to effective volumes of 177-280 kg (that is, higher than that recovered from fourteen 12-1 Niskin bottles). Finally, the effective volume of seawater that passed through Mn-fiber placed in nylon nets and deployed during 4 h ranged between 125 and 364 kg. Consequently, the two techniques that separate Ra isotopes in situ are good alternatives for pre-concentrating radium from seawater. They can save ship-time by avoiding repeated CTD casts to obtain the large volumes of seawater. This is especially true when in situ pumps are deployed to collect suspended particles. However, both methods only provide 228 Ra/ 226 Ra ratios. The

  3. Dimethyl sulfoxide (DMSO) waste residues and municipal waste water odor by dimethyl sulfide (DMS): the north-east WPCP plant of Philadelphia.

    Science.gov (United States)

    Glindemann, Dietmar; Novak, John; Witherspoon, Jay

    2006-01-01

    This study shows for the first time that overlooked mg/L concentrations of industrial dimethyl sulfoxide (DMSO) waste residues in sewage can cause "rotten cabbage" odor problems bydimethyl sulfide (DMS) in conventional municipal wastewater treatment. In laboratory studies, incubation of activated sludge with 1-10 mg/L DMSO in bottles produced dimethyl sulfide (DMS) at concentrations that exceeded the odor threshold by approximately 4 orders of magnitude in the headspace gas. Aeration at a rate of 6 m3 air/m3 sludge resulted in emission of the DMS into the exhaust air in a manner analogous to that of an activated sludge aeration tank. A field study atthe NEWPCP sewage treatment plant in Philadelphia found DMSO levels intermittently peaking as high as 2400 mg/L in sewage near an industrial discharger. After 3 h, the DMSO concentration in the influent to the aeration tank rose from a baseline level of less than 0.01 mg/L to a level of 5.6 mg/L and the DMS concentration in the mixed liquor rose from less than 0.01 to 0.2 mg/L. Finding this link between the intermittent occurrence of DMSO residues in influent of the treatment plant and the odorant DMS in the aeration tank was the keyto understanding and eliminating the intermittent "canned corn" or "rotten cabbage" odor emissions from the aeration tank that had randomly plagued this plant and its city neighborhood for two decades. Sewage authorities should consider having wastewater samples analyzed for DMSO and DMS to check for this possible odor problem and to determine whether DMSO emission thresholds should be established to limit odor generation at sewage treatment plants.

  4. Temperature profile data from surface seawater intake, bucket, and XBT casts in a world wide distribution from 1994-06-29 to 1996-06-08 (NODC Accession 9600120)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected using surface seawater intake, bucket, and XBT casts from multiple vessels in a world wide distribution from June 29, 1994 to...

  5. Temperature profile data from surface seawater intake, bucket, and XBT casts in a world wide distribution from 1996-03-01 to 1997-01-03 (NODC Accession 9700036)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected using surface seawater intake, bucket, and XBT casts from several vessels in a world wide distribution from March 1, 1996 to...

  6. Temperature profile data from surface seawater intake, bucket, and XBT casts in a world wide distribution from 1996-08-11 to 1997-07-16 (NODC Accession 9700213)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile data were collected using surface seawater intake, bucket, and XBT casts in a world wide distribution by several vessels from August 11, 1996 to...

  7. Numerical simulation of freshwater/seawater interaction in a dual-permeability karst system with conduits: the development of discrete-continuum VDFST-CFP model

    Science.gov (United States)

    Xu, Zexuan; Hu, Bill

    2016-04-01

    Dual-permeability karst aquifers of porous media and conduit networks with significant different hydrological characteristics are widely distributed in the world. Discrete-continuum numerical models, such as MODFLOW-CFP and CFPv2, have been verified as appropriate approaches to simulate groundwater flow and solute transport in numerical modeling of karst hydrogeology. On the other hand, seawater intrusion associated with fresh groundwater resources contamination has been observed and investigated in numbers of coastal aquifers, especially under conditions of sea level rise. Density-dependent numerical models including SEAWAT are able to quantitatively evaluate the seawater/freshwater interaction processes. A numerical model of variable-density flow and solute transport - conduit flow process (VDFST-CFP) is developed to provide a better description of seawater intrusion and submarine groundwater discharge in a coastal karst aquifer with conduits. The coupling discrete-continuum VDFST-CFP model applies Darcy-Weisbach equation to simulate non-laminar groundwater flow in the conduit system in which is conceptualized and discretized as pipes, while Darcy equation is still used in continuum porous media. Density-dependent groundwater flow and solute transport equations with appropriate density terms in both conduit and porous media systems are derived and numerically solved using standard finite difference method with an implicit iteration procedure. Synthetic horizontal and vertical benchmarks are created to validate the newly developed VDFST-CFP model by comparing with other numerical models such as variable density SEAWAT, couplings of constant density groundwater flow and solute transport MODFLOW/MT3DMS and discrete-continuum CFPv2/UMT3D models. VDFST-CFP model improves the simulation of density dependent seawater/freshwater mixing processes and exchanges between conduit and matrix. Continuum numerical models greatly overestimated the flow rate under turbulent flow

  8. Modified Mixed Lagrangian-Eulerian Method Based on Numerical Framework of MT3DMS on Cauchy Boundary.

    Science.gov (United States)

    Suk, Heejun

    2016-07-01

    MT3DMS, a modular three-dimensional multispecies transport model, has long been a popular model in the groundwater field for simulating solute transport in the saturated zone. However, the method of characteristics (MOC), modified MOC (MMOC), and hybrid MOC (HMOC) included in MT3DMS did not treat Cauchy boundary conditions in a straightforward or rigorous manner, from a mathematical point of view. The MOC, MMOC, and HMOC regard the Cauchy boundary as a source condition. For the source, MOC, MMOC, and HMOC calculate the Lagrangian concentration by setting it equal to the cell concentration at an old time level. However, the above calculation is an approximate method because it does not involve backward tracking in MMOC and HMOC or allow performing forward tracking at the source cell in MOC. To circumvent this problem, a new scheme is proposed that avoids direct calculation of the Lagrangian concentration on the Cauchy boundary. The proposed method combines the numerical formulations of two different schemes, the finite element method (FEM) and the Eulerian-Lagrangian method (ELM), into one global matrix equation. This study demonstrates the limitation of all MT3DMS schemes, including MOC, MMOC, HMOC, and a third-order total-variation-diminishing (TVD) scheme under Cauchy boundary conditions. By contrast, the proposed method always shows good agreement with the exact solution, regardless of the flow conditions. Finally, the successful application of the proposed method sheds light on the possible flexibility and capability of the MT3DMS to deal with the mass transport problems of all flow regimes. © 2016, National Ground Water Association.

  9. Stabilization of arsenic and lead by magnesium oxide (MgO) in different seawater concentrations.

    Science.gov (United States)

    Kameda, Kentaro; Hashimoto, Yohey; Ok, Yong Sik

    2018-02-01

    Ongoing sea level rise will have a major impact on mobility and migration of contaminants by changing a number of natural phenomena that alter geochemistry and hydrology of subsurface environment. In-situ immobilization techniques may be a promising remediation strategy for mitigating contaminant mobility induced by sea level rise. This study investigated the reaction mechanisms of magnesium oxide (MgO) with aqueous Pb and As under freshwater and seawater using XAFS spectroscopy. Initial concentrations of Pb and As in freshwater strongly controlled the characteristics of the reaction product of MgO. Our study revealed that i) the removal of aqueous Pb and As by MgO was increased by the elevation of seawater concentration, and ii) the removal of As was attributed primarily to (inner-sphere) surface adsorption on MgO, independent on seawater concentrations, and iii) the retention mechanism of Pb was dependent on seawater concentrations where formations of Pb oxides and adsorption on the MgO surface were predominant in solutions with low and high salinity, respectively. The release of As fixed with MgO significantly increased in seawater compared to freshwater, although the amount of As desorbed accounted for <0.2% of total As. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. [Pt(O,O'-acac)(gamma-acac)(DMS)], a new Pt compound exerting fast cytotoxicity in MCF-7 breast cancer cells via the mitochondrial apoptotic pathway.

    Science.gov (United States)

    Muscella, A; Calabriso, N; Fanizzi, F P; De Pascali, S A; Urso, L; Ciccarese, A; Migoni, D; Marsigliante, S

    2008-01-01

    We showed previously that a new Pt complex containing an O,O'-chelated acetylacetonate ligand (acac) and a dimethylsulphide in the Pt coordination sphere, [Pt(O,O'-acac)(gamma-acac)(DMS)], induces apoptosis in HeLa cells. The objective of this study was to investigate the hypothesis that [Pt(O,O'-acac)(gamma-acac)(DMS)] is also cytotoxic in a MCF-7 breast cancer cell line relatively insensitive to cisplatin, and to gain a more detailed analysis of the cell death pathways. Cells were treated with Pt compounds and cytotoxicity tests were performed, together with Western blotting of various proteins involved in apoptosis. The mitochondrial membrane potential was assessed by fluorescence microscopy and spectrofluorometry and the Pt bound to cell fractions was measured by atomic absorption spectrometry. In contrast to cisplatin, the cytotoxicity of [Pt(O,O'-acac)(gamma-acac)(DMS)] correlated with cellular accumulation but not with DNA binding. Also, the Pt content in DNA bases was considerably higher for cisplatin than for [Pt(O,O'-acac)(gamma-acac)(DMS)], thus excluding DNA as a target of [Pt(O,O'-acac)(gamma-acac)(DMS)]. [Pt(O,O'-acac)(gamma-acac)(DMS)] exerted high and fast apoptotic processes in MCF-7 cells since it provoked: (a) mitochondria depolarization; (b) cytochrome c accumulation in the cytosol; (c) translocation of Bax and truncated-Bid from cytosol to mitochondria and decreased expression of Bcl-2; (d) cleavage of caspases -7 and -9, and PARP degradation; (e) chromatin condensation and DNA fragmentation. [Pt(O,O'-acac)(gamma-acac)(DMS)] is highly cytotoxic for MCF-7 cells, cells relatively resistant to many chemotherapeutic agents, as it activates the mitochondrial apoptotic pathway. Hence, [Pt(O,O'-acac)(gamma-acac)(DMS)] has the potential to provide us with new opportunities for therapeutic intervention.

  11. Foundational Report Series. Advanced Distribution management Systems for Grid Modernization (Importance of DMS for Distribution Grid Modernization)

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jianhui [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-09-01

    Grid modernization is transforming the operation and management of electric distribution systems from manual, paper-driven business processes to electronic, computer-assisted decisionmaking. At the center of this business transformation is the distribution management system (DMS), which provides a foundation from which optimal levels of performance can be achieved in an increasingly complex business and operating environment. Electric distribution utilities are facing many new challenges that are dramatically increasing the complexity of operating and managing the electric distribution system: growing customer expectations for service reliability and power quality, pressure to achieve better efficiency and utilization of existing distribution system assets, and reduction of greenhouse gas emissions by accommodating high penetration levels of distributed generating resources powered by renewable energy sources (wind, solar, etc.). Recent “storm of the century” events in the northeastern United States and the lengthy power outages and customer hardships that followed have greatly elevated the need to make power delivery systems more resilient to major storm events and to provide a more effective electric utility response during such regional power grid emergencies. Despite these newly emerging challenges for electric distribution system operators, only a small percentage of electric utilities have actually implemented a DMS. This paper discusses reasons why a DMS is needed and why the DMS may emerge as a mission-critical system that will soon be considered essential as electric utilities roll out their grid modernization strategies.

  12. Spatial distributions of (137)Cs and (239+240)Pu in surface seawater within the Exclusive Economic Zone of East Coast Peninsular Malaysia.

    Science.gov (United States)

    Ahmad, Zaharudin; Mei-Wo, Yii; Abu Bakar, Ahmad Sanadi; Shahar, Hidayah

    2010-09-01

    The studies of (137)Cs and (239+240)Pu distributions in surface seawater at South China Sea within the Exclusive Economic Zone (EEZ) of Peninsular Malaysia were carried out in June 2008. The analysis results will serve as additional information to the expanded baseline data for Malaysia's marine environment. Thirty locations from extended study area were identified in the EEZ from which large volumes of surface seawater samples were collected. Different co-precipitation techniques were employed to concentrate cesium and plutonium separately. A known amount of (134)Cs and (242)Pu tracers were used as yield determinant. The precipitate slurry was collected and oven dried at 60(o)C for 1-2 days. Cesium precipitate was fine-ground and counted using gamma-ray spectrometry system at 661.62keV, while plutonium was separated from other radionuclides using anion exchange, electrodeposited and counted using alpha spectrometry. The activity concentrations of (137)Cs and (239+240)Pu were in the range of 3.40-5.89Bq/m(3) and 2.3-7.9mBq/m(3), respectively. The (239+240)Pu/(137)Cs ratios indicate that there are no new inputs of these radionuclides into the area.

  13. Seawater mesocosm experiments in the Arctic uncover differential transfer of marine bacteria to aerosols.

    Science.gov (United States)

    Fahlgren, Camilla; Gómez-Consarnau, Laura; Zábori, Julia; Lindh, Markus V; Krejci, Radovan; Mårtensson, E Monica; Nilsson, Douglas; Pinhassi, Jarone

    2015-06-01

    Biogenic aerosols critically control atmospheric processes. However, although bacteria constitute major portions of living matter in seawater, bacterial aerosolization from oceanic surface layers remains poorly understood. We analysed bacterial diversity in seawater and experimentally generated aerosols from three Kongsfjorden sites, Svalbard. Construction of 16S rRNA gene clone libraries from paired seawater and aerosol samples resulted in 1294 sequences clustering into 149 bacterial and 34 phytoplankton operational taxonomic units (OTUs). Bacterial communities in aerosols differed greatly from corresponding seawater communities in three out of four experiments. Dominant populations of both seawater and aerosols were Flavobacteriia, Alphaproteobacteria and Gammaproteobacteria. Across the entire dataset, most OTUs from seawater could also be found in aerosols; in each experiment, however, several OTUs were either selectively enriched in aerosols or little aerosolized. Notably, a SAR11 clade OTU was consistently abundant in the seawater, but was recorded in significantly lower proportions in aerosols. A strikingly high proportion of colony-forming bacteria were pigmented in aerosols compared with seawater, suggesting that selection during aerosolization contributes to explaining elevated proportions of pigmented bacteria frequently observed in atmospheric samples. Our findings imply that atmospheric processes could be considerably influenced by spatiotemporal variations in the aerosolization efficiency of different marine bacteria. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  14. The Defense Messaging System (DMS) in the Navy Regional Enterprise Messaging System (NREMS) environment evidence that size does matter in DoD business process engineering

    OpenAIRE

    Ramsey, Avonna S.

    2007-01-01

    Since the migration of DOD messaging to the DMS has been mandated, implementation has been less than ideal and otherwise unsuccessful. DMS users have reported dissatisfaction with the systems maintenance and security support burdens in the current client-server model. NREMS introduces a networked environment capable of push technology and centralized database and security management which should significantly reduce the DMS shortfalls that have made the system lack appeal to the end user. As ...

  15. [The effect of hypertonic seawater and isotonic seawater for nasal mucosa of allergic rhinitis mice model].

    Science.gov (United States)

    Deng, Zhifeng; Xu, Yu; Ou, Jin; Xiang, Rong; Tao, Zezhang

    2014-12-01

    To study the effect of hypertonic seawater and isotonic seawater for nasal mucosa of allergic rhinitis mice model, and explore the possible mechanism of nasal irrigation with seawater in treatment of allergic rhinitis. We used Der pl to make allergic rhinitis model of BALB/c mice, and divided them into three groups randomly. Nasal irrigation with hypertonic seawater (HS) or isotonic seawater (IS) in the treatment group 1-14 days after modeling, and black control (BC) group was given no treatment after modeling. Normal control (NC) group was given no treatment, the number of rubs and sneezings in each group were counted in 30 min after the last nasal irrigation. Mice were then killed 24 h after the last therapy. The noses of mice from each group were removed and fixed, then the slices were stained with hematoxylin and eosin, the others were observed by transmission electron microscope. Mice with hypertonic seawater and isotonic seawater were significantly improved in rubs and sneezings compared to the black control group (P 0. 05); Ciliated columnar epithelium cells in mucosal tissues of HS group and IS group were arranged trimly, better than that in the black control group. Morphology and microstructure in nasal mucosal of HS group was closer to the normal group than in IS group. The injury of nasal mucosa ciliated epithelium was significantly improved by nasal irrigation with hypertonic seawater and isotonic seawater, and the former is better than the latter, the mechanism of nasal irrigation with seawater in treatment of allergic rhinitis may rely on repairing the injured nasal mucosa ciliated epithelium, thereby the symptoms of nasal was reduced.

  16. Temporal variations in dimethylsulphoniopropionate and dimethyl sulphide in the Zuari estuary, Goa (India)

    Digital Repository Service at National Institute of Oceanography (India)

    Shenoy, D.M.; Patil, J.S.

    . F., & Wakeham, S. G. (1998). Temporal variability of dimethyl sulfide and dimethylsulfoniopropionate in the Sargasso Sea. DeepSeaRes.PartI, 45, 2085– 2104. DeSouza, M. P., & Yoch, D. C. (1996). Differential metabolism of dimethyl...) measurements and a procedure to predict sea surface DMS as a function of latitude, longitude, and month.GlobalBiogeochemicalCycles,13, 399–444. Kiene, R. P. (1990). Dimethyl sulfide production from dimethyl-sulfoniopropionate in coastal seawater samples...

  17. Modulation of electromagnetic local density of states by coupling of surface phonon-polariton

    Science.gov (United States)

    Li, Yao; Zhang, Chao-Jie; Wang, Tong-Biao; Liu, Jiang-Tao; Yu, Tian-Bao; Liao, Qing-Hua; Liu, Nian-Hua

    2017-02-01

    We studied the electromagnetic local density of state (EM-LDOS) near the surface of a one-dimensional multilayer structure (1DMS) alternately stacked by SiC and Si. EM-LDOS of a semi-infinite bulk appears two intrinsic peaks due to the resonance of surface phonon-polariton (SPhP) in SiC. In contrast with that of SiC bulk, SPhP can exist at the interface of SiC and Si for the 1DMS. The SPhPs from different interfaces can couple together, which can lead to a significant modulation of EM-LDOS. When the component widths of 1DMS are large, the spectrum of EM-LDOS exhibits oscillation behavior in the frequency regime larger than the resonance frequency of SPhP. While the component widths are small, due to the strong coupling of SPhPs, another peak appears in the EM-LDOS spectrum besides the two intrinsic ones. And the position of the new peak move toward high frequency when the width ratio of SiC and Si increases. The influences of distance from the surfaces and period of 1DMS on EM-LDOS have also been studied in detail. The results are helpful in studying the near-field radiative heat transfer and spontaneous emission.

  18. [Pt(O,O'-acac)(γ-acac)(DMS)] versus cisplatin: apoptotic effects in B50 neuroblastoma cells.

    Science.gov (United States)

    Grimaldi, Maddalena; Santin, Giada; Insolia, Violetta; Dal Bo, Veronica; Piccolini, Valeria Maria; Veneroni, Paola; Barni, Sergio; Verri, Manuela; De Pascali, Sandra Angelica; Fanizzi, Francesco Paolo; Bernocchi, Graziella; Bottone, Maria Grazia

    2016-05-01

    Cisplatin is one of the most active chemotherapeutic agents used in the treatment of childhood and adult malignancies. Cisplatin induces cell death through different pathways. Despite its effectiveness, the continued clinical use of cisplatin is limited by onset of severe side effects (nephrotoxicity, ototoxicity and neurotoxicity) and drug resistance. Therefore, one of the main experimental oncology purpose is related to the search for new platinum-based drugs to create different types of adducts or more specific and effective subcellular targets. Thus, [Pt(O,O'-acac)(γ-acac)(DMS)], which reacts preferentially with protein thiols or thioether, was synthesized. In our research, different approaches were used to compare cisplatin and [Pt(O,O'-acac)(γ-acac)(DMS)] effects in B50 rat neuroblastoma cells. Our results, using immunocytochemical, cytometric and morphological techniques, showed that these compounds exert a cytostatic action and activate apoptosis with different pathways. Long-term effects demonstrated that [Pt(O,O'-acac)(γ-acac)(DMS)] exerts cytotoxic effects in neuronal B50 cell line not inducing drug resistance. Analysis was performed both to compare the ability of these platinum compounds to induce cell death and to investigate the intracellular mechanisms at the basis of their cytotoxicity.

  19. Distribution of lead-210 and polonium-210 between soluble and particulate phases in seawater

    International Nuclear Information System (INIS)

    Spencer, D.W.

    1975-01-01

    Results are reported from radiometric measurements of the distribution of 210 Pb and 210 Po in surface seawater and suspended particulate matter. Samples of plankton and sediments collected from some locations were also analyzed. Samples of seawater and suspended particulate matter were collected from stations located in the Gulf of Maine, the North Atlantic, and approximately 500 miles southwest of Gilbraltar. (U.S.)

  20. In situ glass antifouling using Pt nanoparticle coating for periodic electrolysis of seawater

    Science.gov (United States)

    Xue, Yuxi; Zhao, Jin; Qiu, Ri; Zheng, Jiyong; Lin, Cunguo; Ma, Bojiang; Wang, Peng

    2015-12-01

    In situ electrochemical chlorination is a promising way to prohibit the biofouling on glass used for optical devices in seawater. To make this approach practical, a conductive glass should have low overpotential to generate Cl2, so that the electrical energy consumption, a critical issue for field application, will be low. Moreover, a long sustainability should also be taken into consideration from the application perspective. Following these criteria, we propose Pt/ITO surface to electrochemically generate Cl2, which immunizes biofouling for glass substrate. In this report, firstly, Pt nanoparticle/ITO is prepared via an electrodeposition approach. Secondly, electrocatalysis capability of Pt/ITO is elucidated, which shows the catalysis for Cl2 generation from NaCl solution and seawater has been sparked with Pt on the surface. Also, Pt/ITO is more sustainable and efficient than the bare ITO in natural seawater. Thirdly, the antifouling property is evaluated taking diatom as the target organism. Electrochemical chlorination on Pt/ITO can efficiently prevent the glass from fouling.

  1. Monitoring of uranium isotopes in seaweeds and seawater

    International Nuclear Information System (INIS)

    Meena, Balram; Mehendarge, S.T.; Baburajan, A.; Rao, D.D.

    2012-01-01

    The paper deals with the concentration of uranium in seawater and different types of seaweed found along the coast line of Tarapur marine environment. The seaweeds are the trend indicators of heavy metals and radionuclides present in the aquatic environment. Seaweeds also serve as a food to the marine organisms and thus can enter the human being through food chain. The higher concentration of uranium in seafood may have radiological impact on human health. The Tarapur Atomic Power Station is adjoined to the sea and has a rocky surface area, which act as a good dwelling for the growth and survival of marine biota. In present study, separation and measurements were made to determine the uranium concentration in seaweed seawater at Tarapur coastal environment

  2. Potentiodynamic study of Al-Mg alloy with superhydrophobic coating in photobiologically active/not active natural seawater.

    Science.gov (United States)

    Benedetti, Alessandro; Cirisano, Francesca; Delucchi, Marina; Faimali, Marco; Ferrari, Michele

    2016-01-01

    Superhydrophobic coating technology is regarded as an attractive possibility for the protection of materials in a sea environment. DC techniques are a useful tool to characterize metals' behavior in seawater in the presence/absence of coatings and/or corrosion inhibitors. In this work, investigations concerning Al-5%Mg alloy with and without a sprayed superhydrophobic coating were carried out with potentiodynamic scans in photobiologically active and not active seawater (3 weeks of immersion). In not photobiologically active seawater, the presence of the superhydrophobic coating did not prevent pitting corrosion. With time, the coating underwent local exfoliations, but intact areas still preserved superhydrophobicity. In photobiologically active seawater, on samples without the superhydrophobic coating (controls) pitting was inhibited, probably due to the adsorption of organic compounds produced by the photobiological activity. After 3 weeks of immersion, the surface of the coating became hydrophilic due to diatom coverage. As suggested by intermediate observations, the surface below the diatom layer is suspected of having lost its superhydrophobicity due to early stages of biofouling processes (organic molecule adsorption and diatom attachment/gliding). Polarization curves also revealed that the metal below the coating underwent corrosion inhibiting phenomena as observed in controls, likely due to the permeation of organic molecules through the coating. Hence, the initial biofouling stages (days) occurring in photobiologically active seawater can both accelerate the loss of superhydrophobicity of coatings and promote corrosion inhibition on the underlying metal. Finally, time durability of superhydrophobic surfaces in real seawater still remains the main challenge for applications, where the early stages of immersion are demonstrated to be of crucial importance. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Exploring travelers' behavior in response to dynamic message signs (DMS) using a driving simulator.

    Science.gov (United States)

    2013-10-01

    This research studies the effectiveness of a dynamic message sign (DMS) using a driving : simulator. Over 100 subjects from different socio-economic and age groups were recruited to : drive the simulator under different traffic and driving conditions...

  4. Electrochemical studies of biocorrosion of stainless steel in seawater (A summary of I.C.M.M. research in the field)

    International Nuclear Information System (INIS)

    Scotto, V.

    1989-01-01

    A summary of many years' research in the field is presented. This work has elucidated the mechanism by which a biofilm (slime layer) leads to corrosion of stainless steel in seawater. A layer of slime is deposited and grows on surfaces exposed in seawater. This slime causes the corrosion potential of stainless steel to increase with time of exposure to seawater, apparently because the slime catalyzes the cathodic reduction of oxygen in the water. This paper summarizes the evidence for this mechanism and also discusses the effects of water flow rate, temperature and surface cleaning

  5. Degradation of basalt fibre and glass fibre/epoxy resin composites in seawater

    International Nuclear Information System (INIS)

    Wei Bin; Cao Hailin; Song Shenhua

    2011-01-01

    Research highlights: → BFRP degradation process in seawater environment was first investigated. → The mass gain change includes two effects: absorption and extraction. → The interfacial adhesion of BFRP is bigger than GFRP. → After treated, the bending strength of BFRP is lower than GFRP. → Reducing the Fe 2+ in the basalt fibre could lead to a higher stability of BFRP. - Abstract: Epoxy resins reinforced, respectively, by basalt fibres and glass fibres were treated with a seawater solution for different periods of time. Both the mass gain ratio and the strength maintenance ratio of the composites were examined after the treatment. The fracture surfaces were characterized using scanning electron microscopy. The tensile and bending strengths of the seawater treated samples showed a decreasing trend with treating time. In general, the anti-seawater corrosion property of the basalt fibre reinforced composites was almost the same as that of the glass fibre reinforced ones. Based on the experimental results, possible corrosion mechanisms were explored, indicating that an effective lowering of the Fe 2+ content in the basalt fibre could lead to a higher stability for the basalt fibre reinforced composites in a seawater environment.

  6. Differential Mobility Spectrometry (DMS) Reveals the Elevation of Urinary Acetylcarnitine in Non-Human Primates (NHPs) Exposed to Radiation.

    Science.gov (United States)

    Vera, Nicholas B; Chen, Zhidan; Pannkuk, Evan; Laiakis, Evagelia C; Fornace, Albert J; Erion, Derek M; Coy, Stephen L; Pfefferkorn, Jeffrey A; Vouros, Paul

    2018-03-29

    Acetylcarnitine has been identified as one of several urinary biomarkers indicative of radiation exposure in adult rhesus macaque monkeys (non-human primates, NHPs). Previous work has demonstrated an up-regulated dose-response profile in a balanced male/female NHP cohort 1 . As a contribution toward the development of metabolomics-based radiation biodosimetry in human populations and other applications of acetylcarnitine screening, we have developed a quantitative, high-throughput method for the analysis of acetylcarnitine. We employed the Sciex SelexIon DMS-MS/MS QTRAP 5500 platform coupled to flow injection analysis (FIA), thereby allowing for fast analysis times of less than 0.5 minutes per injection with no chromatographic separation. Ethyl acetate is used as a DMS modifier to reduce matrix chemical background. We have measured NHP urinary acetylcarnitine from the male cohorts that were exposed to the following radiation levels: control, 2 Gy, 4 Gy, 6 Gy, 7 Gy and 10 Gy. Biological variability, along with calibration accuracy of the FIA-DMS-MS/MS method, indicate LOQ of 20 μM, with observed biological levels on the order of 600 μM and control levels near 10 μM. There is an apparent onset of intensified response in the transition from 6 Gy to 10 Gy. The results demonstrate that FIA-DMS-MS/MS is a rapid, quantitative technique that can be utilized for the analysis of urinary biomarker levels for radiation biodosimetry. This article is protected by copyright. All rights reserved.

  7. Seawater predesalination with electrodialysis

    NARCIS (Netherlands)

    Galama, A.H.; Saakes, M.; Bruning, H.; Rijnaarts, H.H.M.; Post, J.W.

    2014-01-01

    The suitability of ED for seawater desalination was investigated and we quantified the energy losses that play a role in electrodialysis. The combination of electrodialysis (ED) and brackish water reverse osmosis (BWRO) is presented as an alternative desalination strategy for seawater reverse

  8. DMSP and DMS dynamics and microzooplankton grazing in the Labrador Sea: application of the dilution technique

    Science.gov (United States)

    Wolfe, Gordon V.; Levasseur, Maurice; Cantin, Guy; Michaud, Sonia

    2000-12-01

    We adapted the dilution technique to study microzooplankton grazing of algal dimethylsulfoniopropionate (DMSP) vs. Chl a, and to estimate the impact of microzooplankton grazing on dimethyl sulfide (DMS) production in the Labrador Sea. Phytoplankton numbers were dominated by autotrophic nanoflagellates in the Labrador basin, but diatoms and colonial Phaeocystis pouchetii contributed significantly to phytomass at several high chlorophyll stations and on the Newfoundland and Greenland shelfs. Throughout the region, growth of algal Chl a and DMSP was generally high (0.2-1 d -1), but grazing rates were lower and more variable, characteristic of the early spring bloom period. Production and consumption of Chl a vs. DMSP followed no clear pattern, and sometimes diverged greatly, likely because of their differing distributions among algal prey taxa and size class. In several experiments where Phaeocystis was abundant, we observed DMS production proportional to grazing rate, and we found clear evidence of DMS production by this haptophyte following physical stress such as sparging or filtration. It is possible that grazing-activated DMSP cleavage by Phaeocystis contributes to grazer deterrence: protozoa and copepods apparently avoided healthy colonies (as judged by relative growth and grazing rates of Chl a and DMSP), and grazing of Phaeocystis was significant only at one station where cells were in poor condition. Although we hoped to examine selective grazing on or against DMSP-containing algal prey, the dilution technique cannot differentiate selective ingestion and varying digestion rates of Chl a and DMSP. We also found that the dilution method alone was poorly suited for assessing the impact of grazing on dissolved sulfur pools, because of rapid microbial consumption and the artifactual release of DMSP and DMS during filtration. Measuring and understanding the many processes affecting organosulfur cycling by the microbial food web in natural populations remain a

  9. The strontium isotopic composition of seawater, and seawater-oceanic crust interaction

    International Nuclear Information System (INIS)

    Spooner, E.T.C.

    1976-01-01

    The 87 Sr/ 86 Sr ratio of seawater strontium (0.7091) is less than the 87 Sr/ 86 Sr ratio of dissolved strontium delivered to the oceans by continental run-off (approximately 0.716). Isotope exchange with strontium isotopically lighter oceanic crust during hydrothermal convection within spreading oceanic ridges can explain this observation. In quantitative terms, the current 87 Sr/ 86 Sr ratio of seawater (0.7091) may be maintained by balancing the continental run-off flux of strontium (0.59 x 10 12 g/yr) against a hydrothermal recirculation flux of 3.6 x 10 12 g/yr, during which the 87 Sr/ 86 Sr ratio of seawater drops by 0.0011. A concomitant mean increase in the 87 Sr/ 86 Sr ratio of the upper 4.5 km of oceanic crust of 0.0010 (0.7029-0.7039) should be produced. This required 87 Sr enrichment has been observed in hydrothermally metamorphosed ophiolitic rocks from the Troodos Massif, Cyprus. The post-Upper Cretaceous increase in the strontium isotopic composition of seawater (approximately 0.7075-0.7091) covaries smoothly with inferred increase in land area. This suggests that during this period the main factor which has caused variability in the 87 Sr/ 86 Sr ratio of seawater strontium could have been variation in the magnitude of the continental run-off flux caused by variation in land area. Variations in land area may themselves have been partly a consequence of variations in global mean sea-floor spreading rate. (Auth.)

  10. Dynamics of dimethylsulphoniopropionate and dimethylsulphide under different CO2 concentrations during a mesocosm experiment

    Directory of Open Access Journals (Sweden)

    C. LeQuéré

    2008-03-01

    Full Text Available The potential impact of seawater acidification on the concentrations of dimethylsulfide (DMS and dimethylsulfoniopropionate (DMSP, and the activity of the enzyme DMSP-lyase was investigated during a pelagic ecosystem CO2 enrichment experiment (PeECE III in spring 2005. Natural phytoplankton blooms were studied for 24 days under present, double and triple partial pressures of CO2 (pCO2; pH=8.3, 8.0, 7.8 in triplicate 25 m3 enclosures. The results indicate similar DMSP concentrations and DMSP-lyase activity (DLA patterns for all treatments. Hence, DMSP and DLA do not seem to have been affected by the CO2 treatment. In contrast, DMS concentrations showed small but statistically significant differences in the temporal development of the low versus the high CO2 treatments. The low pCO2 enclosures had higher DMS concentrations during the first 10 days, after which the levels decreased earlier and more rapidly than in the other treatments. Integrated over the whole study period, DMS concentrations were not significantly different from those of the double and triple pCO2 treatments. Pigment and flow-cytometric data indicate that phytoplanktonic populations were generally similar between the treatments, suggesting a certain resilience of the marine ecosystem under study to the induced pH changes, which is reflected in DMSP and DLA. However, there were significant differences in bacterial community structure and the abundance of one group of viruses infecting nanoeukaryotic algae. The amount of DMS accumulated per total DMSP or chlorophyll-a differed significantly between the present and future scenarios, suggesting that the pathways for DMS production or bacterial DMS consumption were affected by seawater pH. A comparison with previous work (PeECE II suggests that DMS concentrations do not respond consistently to pelagic ecosystem CO2 enrichment experiments.

  11. DmsD, a Tat system specific chaperone, interacts with other general chaperones and proteins involved in the molybdenum cofactor biosynthesis

    OpenAIRE

    Li, Haiming; Chang, Limei; Howell, Jenika M.; Turner, Raymond J.

    2010-01-01

    Many bacterial oxidoreductases depend on the Tat translocase for correct cell localization. Substrates for the Tat translocase possess twin-arginine leaders. System specific chaperones or redox enzyme maturation proteins (REMPs) are a group of proteins implicated in oxidoreductase maturation. DmsD is a REMP discovered in Escherichia coli, which interacts with the twin-arginine leader sequence of DmsA, the catalytic subunit of DMSO reductase. In this study, we identified several potential inte...

  12. Effect of seawater salinity on pore-size distribution on a poly(styrene)-based HP20 resin and its adsorption of diarrhetic shellfish toxins.

    Science.gov (United States)

    Fan, Lin; Sun, Geng; Qiu, Jiangbing; Ma, Qimin; Hess, Philipp; Li, Aifeng

    2014-12-19

    In the present study, okadaic acid (OA) and dinophysistoxin-1 (DTX1) were spiked into artificial seawater at low, medium and high estuarine salinities (9‰, 13.5‰ and 27‰). Passive samplers (HP20 resin) used for solid phase adsorption toxin tracking (SPATT) technology were exposed in these seawaters for 12-h periods. Adsorption curves well fitted a pseudo-secondary kinetics model. The highest initial sorption rates of both toxins occurred in the seawater of medium salinity, followed by seawater of low and high estuarine salinity. Pore volumes of micropores (seawater at high and low salinity but not in seawater at medium salinity, which demonstrated that the toxin molecules entered into micropores and mesopores (below 10nm in size) in seawaters of high and low salinity. More toxin or other matrix agglomerates were displayed on the surface of resin deployed in the seawater of medium salinity. Taking into consideration the pore-size distribution and surface images, it appears that intra-particle diffusion governs toxin adsorption in seawater at high salinity while film diffusion mainly controls the adsorption process in seawater at medium salinity. This is the first study to confirm that molecules of OA and DTX1 are able to enter into micropores (seawater with high salinity (∼27‰). Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Isolation of Methylophaga spp. from Marine Dimethylsulfide-Degrading Enrichment Cultures and Identification of Polypeptides Induced during Growth on Dimethylsulfide▿

    OpenAIRE

    Schäfer, Hendrik

    2007-01-01

    Dimethylsulfide (DMS)-degrading enrichment cultures were established from samples of coastal seawater, nonaxenic Emiliania huxleyi cultures, and mixed marine methyl halide-degrading enrichment cultures. Bacterial populations from a broad phylogenetic range were identified in the mixed DMS-degrading enrichment cultures by denaturing gradient gel electrophoresis (DGGE). Sequences of dominant DGGE bands were similar to those of members of the genera Methylophaga and Alcanivorax. Several closely ...

  14. Performance and flow characteristics of MHD seawater thruster

    Energy Technology Data Exchange (ETDEWEB)

    Doss, E.D.

    1990-01-01

    The main goal of the research is to investigate the effects of strong magnetic fields on the electrical and flow fields inside MHD thrusters. The results of this study is important in the assessment of the feasibility of MHD seawater propulsion for the Navy. To accomplish this goal a three-dimensional fluid flow computer model has been developed and applied to study the concept of MHD seawater propulsion. The effects of strong magnetic fields on the current and electric fields inside the MHD thruster and their interaction with the flow fields, particularly those in the boundary layers, have been investigated. The results of the three-dimensional computations indicate that the velocity profiles are flatter over the sidewalls of the thruster walls in comparison to the velocity profiles over the electrode walls. These nonuniformities in the flow fields give rise to nonuniform distribution of the skin friction along the walls of the thrusters, where higher values are predicted over the sidewalls relative to those over the electrode walls. Also, a parametric study has been performed using the three-dimensional MHD flow model to analyze the performance of continuous electrode seawater thrusters under different operating parameters. The effects of these parameters on the fluid flow characteristics, and on the thruster efficiency have been investigated. Those parameters include the magnetic field (10--20 T), thruster diameter, surface roughness, flow velocity, and the electric load factor. The results show also that the thruster performance improves with the strength of the magnetic field and thruster diameter, and the efficiency decreases with the flow velocity and surface roughness.

  15. Seawater ultrafiltration fouling control: Backwashing with demineralized water/SWRO permeate

    KAUST Repository

    Li, Sheng; Heijman, Sebastiaan G J; Verberk, J. Q J C; Amy, Gary L.; Van Dijk, Johannis C.

    2012-01-01

    In this study, the effect of demineralized water backwashing on fouling control of seawater ultrafiltration was investigated. Seawater from Scheveningen beach in The Hague and a desalination plant of Evides Company at Zeeland in the Netherlands was used as feed water, while demineralized water and UF permeate were used as backwash water for a fouling control efficiency comparison under different fluxes and backwash durations. Furthermore, demineralized waters with 5 or 50 mmol/l NaCl were applied for backwashing as well, to check the influence of monovalent cations on UF fouling control. Additionally, SWRO permeate was used for backwashes in long-term experiments to check the possibility of it replacing demineralized water. Results show that seawater UF fouling control is substantially improved by demineralized water backwashing. However, due to the high salinity of seawater, more water was required to dilute the cation concentration and limit the dispersion effect near the membrane surface than was needed for surface water. A 2-min demineralized water backwash showed better fouling control efficiency than a 1-min backwash. Furthermore, the presence of monovalent cations in the backwash water deteriorated the fouling control efficiency of the backwash, indicating the existence of a charge screening effect. The demineralized water with 5 and 50 mmol/l NaCl both showed a similar fouling control efficiency which is better than the UF permeate backwash. The calcium ions in UF permeate probably deteriorates the fouling control efficiency by maintaining a Ca-bridging effect between the membranes and NOM. SWRO permeate backwashing successfully controls membrane fouling as well. © 2012 Elsevier B.V. All rights reserved.

  16. Seawater ultrafiltration fouling control: Backwashing with demineralized water/SWRO permeate

    KAUST Repository

    Li, Sheng

    2012-09-01

    In this study, the effect of demineralized water backwashing on fouling control of seawater ultrafiltration was investigated. Seawater from Scheveningen beach in The Hague and a desalination plant of Evides Company at Zeeland in the Netherlands was used as feed water, while demineralized water and UF permeate were used as backwash water for a fouling control efficiency comparison under different fluxes and backwash durations. Furthermore, demineralized waters with 5 or 50 mmol/l NaCl were applied for backwashing as well, to check the influence of monovalent cations on UF fouling control. Additionally, SWRO permeate was used for backwashes in long-term experiments to check the possibility of it replacing demineralized water. Results show that seawater UF fouling control is substantially improved by demineralized water backwashing. However, due to the high salinity of seawater, more water was required to dilute the cation concentration and limit the dispersion effect near the membrane surface than was needed for surface water. A 2-min demineralized water backwash showed better fouling control efficiency than a 1-min backwash. Furthermore, the presence of monovalent cations in the backwash water deteriorated the fouling control efficiency of the backwash, indicating the existence of a charge screening effect. The demineralized water with 5 and 50 mmol/l NaCl both showed a similar fouling control efficiency which is better than the UF permeate backwash. The calcium ions in UF permeate probably deteriorates the fouling control efficiency by maintaining a Ca-bridging effect between the membranes and NOM. SWRO permeate backwashing successfully controls membrane fouling as well. © 2012 Elsevier B.V. All rights reserved.

  17. Sustainable and safe energy supply with seawater uranium fueled HTGR and its economy

    International Nuclear Information System (INIS)

    Fukaya, Y.; Goto, M.

    2017-01-01

    Highlights: • We discussed uranium resources with an energy security perspective. • We concluded seawater uranium is preferable for sustainability and energy security. • We evaluated electricity generation cost of seawater uranium fueled HTGR. • We concluded electricity generation with seawater uranium is reasonable. - Abstract: Sustainable and safe energy supply with High Temperature Gas-cooled Reactor (HTGR) fueled by uranium from seawater have been investigated and discussed. From the view point of safety feature of self-regulation with thermal reactor of HTGR, the uranium resources should be inexhaustible. The seawater uranium is expected to be alternative resources to conventional resources because it exists so much in seawater as a solute. It is said that 4.5 billion tons of uranium is dissolved in the seawater, which corresponds to a consumption of approximately 72 thousand years. Moreover, a thousand times of the amount of 4.5 trillion tU of uranium, which corresponds to the consumption of 72 million years, also is included in the rock on the surface of the sea floor, and that is also recoverable as seawater uranium because uranium in seawater is in an equilibrium state with that. In other words, the uranium from seawater is almost inexhaustible natural resource. However, the recovery cost with current technology is still expensive compared with that of conventional uranium. Then, we assessed the effect of increase in uranium purchase cost on the entire electricity generation cost. In this study, the economy of electricity generation of cost of a commercial HTGR was evaluated with conventional uranium and seawater uranium. Compared with ordinary LWR using conventional uranium, HTGR can generate electricity cheaply because of small volume of simple direct gas turbine system compared with water and steam systems of LWR, rationalization by modularizing, and high thermal efficiency, even if fueled by seawater uranium. It is concluded that the HTGR

  18. Determining subnanomolar iron concentrations in oceanic seawater using a siderophore-modified film analyzed by infrared spectroscopy.

    Science.gov (United States)

    Roy, Eric G; Jiang, Cuihong; Wells, Mark L; Tripp, Carl

    2008-06-15

    Iron is a bioactive trace element in seawater that regulates photosynthetic carbon dioxide drawdown and export from surface waters by phytoplankton in upward of 40% of the world's oceans. While autonomous sensor arrays are beginning to provide high-resolution data on temporal and spatial scales for some key oceanographic parameters, current analytical methods for iron are not amenable to autonomous platforms because of the need for user involvement and wet chemistry-based approaches. As a result, very large gaps remain in our understanding of iron distribution and chemistry in seawater. Here we present a straightforward nanostructure-based method to measure dissolved iron in natural seawater. The device comprises an iron-specific chelating biomolecule, desferrioxamine B (DFB), covalently immobilized on a mesoporous silica film. Changes in infrared spectral signatures of the immobilized DFB upon Fe(III) complexation provide an accurate and precise measure of iron on the surface of a chip exposed to seawater. The current system has a detection limit of approximately 50 pM for a 1-L sample at pH 1.7 and was used to measure dissolved iron in subarctic Pacific waters without interference from other elements in seawater. This technology provides a major step toward obtaining accurate iron measurements on autonomous research platforms.

  19. Impact of the surface roughness of AISI 316L stainless steel on biofilm adhesion in a seawater-cooled tubular heat exchanger-condenser.

    Science.gov (United States)

    García, Sergio; Trueba, Alfredo; Vega, Luis M; Madariaga, Ernesto

    2016-11-01

    The present study evaluated biofilm growth in AISI 316L stainless steel tubes for seawater-cooled exchanger-condensers that had four different arithmetic mean surface roughness values ranging from 0.14 μm to 1.2 μm. The results of fluid frictional resistance and heat transfer resistance regarding biofilm formation in the roughest surface showed increases of 28.2% and 19.1% respectively, compared with the smoothest surface. The biofilm thickness taken at the end of the experiment showed variations of up to 74% between the smoothest and roughest surfaces. The thermal efficiency of the heat transfer process in the tube with the roughest surface was 17.4% greater than that in the tube with the smoothest surface. The results suggest that the finish of the inner surfaces of the tubes in heat exchanger-condensers is critical for improving energy efficiency and avoiding biofilm adhesion. This may be utilised to reduce biofilm adhesion and growth in the design of heat exchanger-condensers.

  20. Top down control of post-upwelling waters off Trivandrum: Indications from variability in DMS(P)

    Digital Repository Service at National Institute of Oceanography (India)

    Pandey S.; Bhonsle S.; RituKumari; Gauns, M.; LokaBharathi, P.A.

    sink also produce a tertiary sulfonium compound dimethylsulphoniopropionate (DMSP), which breaks down mostly by bacterial mediation to a climatically relevant volatile compound dimethylsulphide (DMS). In order to probe the dynamics of DMSP in post...

  1. Impact of seawater [Ca

    NARCIS (Netherlands)

    Mewes, A.; Langer, G.; Thoms, S.; Nehrke, G.; Reichart, G.J.; de Nooijer, L.J.; Bijma, J.

    2015-01-01

    Mg / Ca ratios in foraminiferal tests are routinely used as paleotemperature proxies, but on long timescales, they also hold the potential to reconstruct past seawater Mg / Ca. The impact of both temperature and seawater Mg / Ca on Mg incorporation in Foraminifera has been quantified by a number of

  2. Foundational Report Series: Advanced Distribution Management Systems for Grid Modernization, Business Case Calculations for DMS

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Xiaonan [Argonne National Lab. (ANL), Argonne, IL (United States); Singh, Ravindra [Argonne National Lab. (ANL), Argonne, IL (United States); Wang, Jianhui [Argonne National Lab. (ANL), Argonne, IL (United States); Reilly, James T. [Reilly Associates, Pittson, PA (United States)

    2017-01-01

    Distribution Management System (DMS) applications require a substantial commitment of technical and financial resources. In order to proceed beyond limited-scale demonstration projects, utilities must have a clear understanding of the business case for committing these resources that recognizes the total cost of ownership. Many of the benefits provided by investments in DMSs do not translate easily into monetary terms, making cost-benefit calculations difficult. For example, Fault Location Isolation and Service Restoration (FLISR) can significantly reduce customer outage duration and improve reliability. However, there is no well-established and universally-accepted procedure for converting these benefits into monetary terms that can be compared directly to investment costs. This report presents a methodology to analyze the benefits and costs of DMS applications as fundamental to the business case.

  3. Characterization of the corrosion behavior of different stainless steel alloys exposed to flowing fresh seawater, using E.I.S technique

    Energy Technology Data Exchange (ETDEWEB)

    Al Muhanna, K. [Petroleum Research and Studies Center, Kuwait Institute for Scientific Research, KISR, P.O.Box 24885, Safat 13109 Kuwait (Kuwait)

    2004-07-01

    E.I.S technique was used to characterize the corrosion behavior of UNS NO. S 31600 stainless steel, UNS NO. S 30400 stainless steel and UNS NO. S 62800 sanicro 28 exposed to continuous fresh Seawater. The total exposure time of the test was about 180 days. Two types of additives (4 ppm of Cl{sub 2} and 5 ppm of NH{sub 3}) were also added to the seawater to investigate their effect on the surfaces of these alloys. During the tests, no marine - macro fouling was observed on the surfaces of the tested alloys, as the seawater was filtrated at the Doha Desalination Research Center, where the study was carried out, but only a slimy layer spread on the whole surface of the alloys. The corrosion behavior of each alloy was monitored by the open circuit potential measurement, and the E.I.S technique using the EG and G 352 software and hardware instrument, where the resistance of the solution (R{sub sol}), the resistance of the surface of the tested alloy (R{sub p}), and the double layer capacitance (Cdl) was calculated. Under this study's experimental conditions, results indicated that the stainless steel alloys were highly resistant to marine fouling and corrosion in seawater, and were not affected by the aggressive additives, such as NH{sub 3}, and Cl{sub 2} in the seawater. (author)

  4. Preparation of nanometer sized Mn doped Zn based oxides powder for DMS applications

    CSIR Research Space (South Africa)

    Das, J

    2009-01-01

    Full Text Available In order to study the size dependent DMS (Diluted Magnetic Semiconductor) behavior of Mn doped ZnO, the authors have systematically prepared a series of nanosized green powder based on Mn doped ZnO (Zn 1-x Mn x O, where x=0.02 - 0.1) materials using...

  5. ``DMS-R, the Brain of the ISS'', 10 Years of Continuous Successful Operation in Space

    Science.gov (United States)

    Wolff, Bernd; Scheffers, Peter

    2012-08-01

    Space industries on both sides of the Atlantic were faced with a new situation of collaboration in the beginning of the 1990s.In 1995, industrial cooperation between ASTRIUM ST, Bremen and RSC-E, Moscow started aiming the outfitting of the Russian Service Module ZVEZDA for the ISS with computers. The requested equipments had to provide not only redundancy but fault tolerance and high availability. The design and development of two fault tolerant computers, (FTCs) responsible for the telemetry (Telemetry Computer: TC) and the central control (CC), as well as the man machine interface CPC were contracted to ASTRIUM ST, Bremen. The computer system is responsible e.g. for the life support system and the ISS re-boost control.In July 2000, the integration of the Russian Service Module ZVEZDA with Russian ZARYA FGB and American Node 1 bears witness for transatlantic and European cooperation.The Russian Service module ZVEZDA provides several basic functions as Avionics Control, the Environmental Control and Life Support (ECLS) in the ISS and control of the docked Automatic Transfer Vehicle (ATV) which includes re-boost of ISS. If these elementary functions fail or do not work reliable the effects for the ISS will be catastrophic with respect to Safety (manned space) and ISS mission.For that reason the responsible computer system Data Management System - Russia (DMS-R) is also called "The brain of the ISS".The Russian Service module ZVEZDA, including DMS-R, was launched on 12th of July, 2000. DMS-R was operational also during launch and docking.The talk provide information about the definition, design and development of DMS-R, the integration of DMS-R in the Russian Service module and the maintenance of the system in space. Besides the technical aspects are also the German - Russian cooperation an important subject of this speech. An outlook finalises the talk providing further development activities and application of fault tolerant systems.The importance of the DMS

  6. Concentration of 99Tc in seawater by coprecipitation with iron hydroxide

    International Nuclear Information System (INIS)

    Momoshima, Noriyuki; Eto, Ichiro; Muhammad Sayad; Takashima, Yoshimasa

    1991-01-01

    A method for accumulation of 99 Tc in seawater has been developed. Technetium tracer in +VII oxidation state was added to the seawater together with reducing agent, potassium pyrosulfite, and coprecipitation agent, ferric chloride. After reduction of Tc(VII) at pH 4, Tc(IV) was coprecipitated as iron hydroxide by addition of sodium hydroxide to pH 9. The reduction and coprecipitation was quantitative and overall recovery of Tc was more than 98%. The green color of iron precipitate formed at pH 9 suggested that Tc(VII) as well as ferric ion was reduced under this condition. Adsorption of Tc(IV), however, was poor for iron hydroxide which was prepared in advance indicating active surface of freshly precipitated iron hydroxide is necessary for quantitative recovery of Tc(IV). A repeating coprecipitation technique was examined for enrichment of Tc in seawater that the same iron was used repeatedly as coprecipitater. After separation of iron hydroxide with Tc(IV) from supernatant, the precipitate was dissolved by addition of acid and then new seawater which contained reducing agent and Tc(VII) was added. Reduction and coprecipitation was again carried out. Good recovery was attained for 7 repeats. The proposed repeating coprecipitation technique was applicable to a large amount of seawater without increasing the amount of iron hydroxide which is subjected to radiochemical analysis. (author)

  7. Sorption isolation of strontium from seawater

    International Nuclear Information System (INIS)

    Avramenko, V.A.; Zheleznov, V.V.; Kaplun, E.V.; Sokol'nitskaya, T.A.; Yukhkam, A.A.

    2001-01-01

    Sorption isolation of strontium from seawater is considered and prospects of use of selective adsorbents for purification of seawater or liquid radioactive wastes mixed with seawater from 90 Sr are discussed. Comparative analysis of sorptive properties of adsorbents of different nature is done. It is shown that sorption-reagent materials developed by authors can to afford effective separation of 90 Sr from seawater. Possible mechanism of strontium sorption by these adsorbents is considered. The prospect of their use for purification of liquid radioactive wastes from strontium is shown [ru

  8. Distributions and Relationships of CO2, O2, and Dimethylsulfide in the Changjiang (Yangtze) Estuary and Its Adjacent Waters in Summer

    Science.gov (United States)

    Wu, Xi; Tan, Tingting; Liu, Chunying; Li, Tie; Liu, Xiaoshou; Yang, Guipeng

    2018-04-01

    The distributions and relationships of O2, CO2, and dimethylsulfide (DMS) in the Changjiang (Yangtze) Estuary and its adjacent waters were investigated in June 2014. In surface water, mean O2 saturation level, partial pressure of CO2 (pCO2), and DMS concentrations (and ranges) were 110% (89%-167%), 374 μatm (91-640 μatm), and 8.53 nmol L-1 (1.10-27.50 nmol L-1), respectively. The sea-to-air fluxes (and ranges) of DMS and CO2 were 8.24 μmol m-2 d-1 (0.26-62.77 μmol m-2 d-1), and -4.7 mmol m-2 d-1 (-110.8-31.7 mmol m-2 d-1), respectively. Dissolved O2 was oversaturated, DMS concentrations were relatively high, and this region served as a sink of atmospheric CO2. The pCO2 was significantly and negatively correlated with the O2 saturation level, while the DMS concentration showed different positive relationships with the O2 saturation level in different water masses. In vertical profiles, a hypoxic zone existed below 20 m at a longitude of 123°E. The stratification of temperature and salinity caused by the Taiwan Warm Current suppressed seawater exchange between upper and lower layers, resulting in the formation of a hypoxic zone. Oxidative decomposition of organic detritus carried by the Changjiang River Diluted Water (CRDW) consumed abundant O2 and produced additional CO2. The DMS concentrations decreased because of low phytoplankton biomass in the hypoxic zone. Strong correlations appeared between the O2 saturation level, pCO2 and DMS concentrations in vertical profiles. Our results strongly suggested that CRDW played an important role in the distributions and relationships of O2, CO2, and DMS.

  9. Chemical Characteristics of Seawater and Sediment in the Yap Trench

    Science.gov (United States)

    Ding, H.; Sun, C.; Yang, G.

    2017-12-01

    In June 2016, seawater samples at sediment-seawater interface and sediment samples were collected by the he Jiaolong, China's manned submersible, at four sampling sites located in the Yap Trench. Seawater samples from different depths of the trench were also collected by CTD. Chemical parameters, including pH, alkanility, concentrations of dissolved inorganic carbon, dissolved and total organic carbon, methane, dimethylsulfoniopropionate, nutrients, carbohydrates, and amino acids were analyzed in the seawater samples. Concentrations of total organic carbon, six constant elements and nine trace elements were determined in the sediment samples. All the vertical profiles of the chemical parameters in the seawater have unique characteristics. Our resluts also showed that the carbonate compensation depth (CCD) was between 4500 m and 5000 m in the trench. The hadal sediment at 6500 m depth under the CCD line was siliceous ooze favored for the burial of orgaic carbon, attributed to accumulation of surface sediment by gravity flow. The abyssal sediment at the 4500 m depth was calcareous ooze. Various microfossils, such as discoasters and diatoms, were identified in different sediment layers of the sediment samples.Based on the ratios of Fe/Al and Ti/Al, and the correlation between different elements, the sediment in the Yap Trench were derived from biogenic, terrestrial, volcanic and autogenic sources. The ratios of Ni/Co and V/Cr showed that the deposition environment of the trench should be oxidative, arributed to inflow of the Antractic bottom oxygen-rich seawater.The high concentraiont of Ca in the sediment from the station 371-Yap-S02 below 4 cm depth indicated that there was no large-scale volcanic eruption in the research area and the volcanic materials in the sediment might orginated from the Mariana Volcanic Arc, and the Carolyn Ridge has been slowly sinking on the east side of the trench due to plate subduction. This study is the first systematic study of

  10. Sulphide production and corrosion in seawaters during exposure to FAME diesel.

    Science.gov (United States)

    Lee, Jason S; Ray, Richard I; Little, Brenda J; Duncan, Kathleen E; Oldham, Athenia L; Davidova, Irene A; Suflita, Joseph M

    2012-01-01

    Experiments were designed to evaluate the corrosion-related consequences of storing/transporting fatty acid methyl ester (FAME) alternative diesel fuel in contact with natural seawater. Coastal Key West, FL (KW), and Persian Gulf (PG) seawaters, representing an oligotrophic and a more organic- and inorganic mineral-rich environment, respectively, were used in 60 day incubations with unprotected carbon steel. The original microflora of the two seawaters were similar with respect to major taxonomic groups but with markedly different species. After exposure to FAME diesel, the microflora of the waters changed substantially, with Clostridiales (Firmicutes) becoming dominant in both. Despite low numbers of sulphate-reducing bacteria in the original waters and after FAME diesel exposure, sulphide levels and corrosion increased markedly due to microbial sulphide production. Corrosion morphology was in the form of isolated pits surrounded by an intact, passive surface with the deepest pits associated with the fuel/seawater interface in the KW exposure. In the presence of FAME diesel, the highest corrosion rates measured by linear polarization occurred in the KW exposure correlating with significantly higher concentrations of sulphur and chlorine (presumed sulphide and chloride, respectively) in the corrosion products.

  11. Development of radioactive seawater monitors, 1

    International Nuclear Information System (INIS)

    Fukushima, Masanori

    1989-01-01

    Applicability of some adsorptive materials to monitoring of radioactive seawater is generalized. Studied techniques that allow utilization of adsorptive materials in monitoring radioactive seawater are the substitute methods using sampled seawater or indicator plants such as gulfweed and the method using adsorptive materials for continuous monitoring of underwater radioactivity, the method using them for field measurement of under water radioactivity from a boat, and the method using an adsorptive material moored underwater for integration monitoring of underwater radioactivity. Selected adsorptive materials that were judged suitable for monitoring radioactive seawater is the one composed of some kind of adsorptive compound (manganese dioxide or ferrocyan cobalt potassium) fixed to crylic cellulose. This adsorptive material permits selective scavenging radioactive Cs, Mn, Co, Zn, Ce, Fe, Ru, Ra Th, Pu and Am from seawater. (aurhor)

  12. Studies on rare earth elements in seawater and uptake by marine organisms

    International Nuclear Information System (INIS)

    Suzuki, H.; Koyanagi, T.; Saiki, M.

    1975-01-01

    The contents of rare earth elements in marine environmental samples were determined by neutron activation analysis to examine the existing state in coastal seawater and the concentration by marine organisms of the elements. Seawater was filtered through a Millipore filter GS (pore size 0.22 μm), before the analysis. Some of the seawater was treated with HC1 solution before filtration and some after filtration. Certain marine organisms were also analysed for determination of rare earth elements. These were: flounder (Paralichthys olivaceus); yellowtails (Seriola quinqueradiata); immature anchovy (Engraulis japonica); clams (Meretrix lusoria); green algae (Ulva pertusa); brown algae (Hizikia fusiforme, Sargassum fulvellum, Undaria pinnatifida). In the seawater without HC1 treatment before filtration, considerable amounts of the elements existed in residue on the filter, whereas in the seawater treated with HC1 before filtration, the greater part remained in the dissolved state. Concentration factors calculated from the contents of stable elements, therefore, are affected remarkably by the existing state of the elements in seawater. If only the dissolved state is assumed available for marine organisms, values one order higher are attained compared with the case where total amounts of the elements were used for the calculation. However, the contribution of the insoluble state seems to be not negligible with some organisms. The higher concentration factors for immature anchovy and clams observed in this study were considered to be caused by surface adsorption of elements in particulate form and also ingested sediment with high element concentration. (author)

  13. Roseovarius azorensis sp. nov., isolated from seawater at Espalamaca, Azores

    Digital Repository Service at National Institute of Oceanography (India)

    Rajasabapathy, R.; Mohandass, C; Dastager, S.G.; Liu, Q.; Khieu, T.-N.; Son, C; Li, W.-J; Colaco, A.

    A Gram-negative, motile, non-spore forming, rod shaped aerobic bacterium, designated strain SSW084T, was isolated from a surface seawater sample collected at Espalamaca (38°33`N; 28°39`W), Azores. Growth was found to occur from 15 to 40...

  14. Sunlight-enhanced calcareous deposition on cathodic stainless steel in natural seawater

    Digital Repository Service at National Institute of Oceanography (India)

    Eashwar, M.; SathishKumar, P.; Ravishankar, R.; Subramanian, G.

    In replicate series of experiments in natural seawater, one in full darkness and the other in a 1:1 diurnal cycle with as little as 5 percent of natural solar illumination, sunlight promoted calcareous deposition on cathodic stainless steel surfaces...

  15. Physiological responses of coccolithophores to abrupt exposure of naturally low pH deep seawater.

    Science.gov (United States)

    Iglesias-Rodriguez, Maria Debora; Jones, Bethan M; Blanco-Ameijeiras, Sonia; Greaves, Mervyn; Huete-Ortega, Maria; Lebrato, Mario

    2017-01-01

    Upwelling is the process by which deep, cold, relatively high-CO2, nutrient-rich seawater rises to the sunlit surface of the ocean. This seasonal process has fueled geoengineering initiatives to fertilize the surface ocean with deep seawater to enhance productivity and thus promote the drawdown of CO2. Coccolithophores, which inhabit many upwelling regions naturally 'fertilized' by deep seawater, have been investigated in the laboratory in the context of ocean acidification to determine the extent to which nutrients and CO2 impact their physiology, but few data exist in the field except from mesocosms. Here, we used the Porcupine Abyssal Plain (north Atlantic Ocean) Observatory to retrieve seawater from depths with elevated CO2 and nutrients, mimicking geoengineering approaches. We tested the effects of abrupt natural deep seawater fertilization on the physiology and biogeochemistry of two strains of Emiliania huxleyi of known physiology. None of the strains tested underwent cell divisions when incubated in waters obtained from seawater from ~1,000 m (pH = 7.9; CO2 ~560 p.p.m.; 14-17 μM nitrate) and ~4,800 m (pH = 7.9; CO2 ~600 p.p.m.; 21 μM nitrate). Emiliania huxleyi strain CCMP 88E showed no differences in growth rate or in cellular content or production rates of particulate organic (POC) and inorganic (PIC) carbon and cellular particulate organic nitrogen (PON) between treatments using water from 1,000 m and 4,800 m. However, despite the N:P ratio of seawater being comparable in water from ~1,000 and ~4,800 m, the PON production rates were three times lower in one incubation using water from ~1,000 m compared to values observed in water from ~4,800 m. Thus, the POC:PON ratios were threefold higher in cells that were incubated in ~1,000 m seawater. The heavily calcified strain NZEH exhibited lower growth rates and PIC production rates when incubated in water from ~4,800 m compared to ~1,000 m, while cellular PIC, POC and PON were higher in water from 4,800 m

  16. 99Tc in seawater in the West Spitsbergen Current and adjacent areas

    International Nuclear Information System (INIS)

    Gerland, Sebastian; Lind, Bjoern; Dowdall, Mark; Karcher, M.; Kolstad, Anne Kathrine

    2003-01-01

    99 Tc levels were measured in seawater samples collected between 2000 and 2002 in the West Spitsbergen Current (WSC) and along the western coast of Svalbard or Spitzbergen and compared with available oceanographic 3-D modelling results for the late 1990s. Additional data from related regions are also presented in order to support the data interpretation. The seawater in the Arctic fjord Kongsfjorden on the western coast of Svalbard is influenced by the WSC, as shown by the 99 Tc levels in surface water. By means of the WSC, 99 Tc reaches the Eastern Fram Strait, where one branch of the WSC turns west into the East Greenland Current (EGC), and another branch continues northwards into the Arctic Ocean. Surface seawater collected in the central part of the WSC during a cruise on board the R/V 'Polarstern' in the summer of 2000, showed higher levels of 99 Tc than samples measured in Kongsfjorden in the spring of 2000. However, all levels measured in surface water are of the same order of magnitude. Data from sampling of deeper water in the WSC and EGC provide information pertaining to the lateral distribution of 99 Tc. In all vertical profiling surveys (conducted in spring and summer), the highest levels of 99 Tc were found in surface water. Comparison with oceanographic 3-D modelling indicates both significant seasonal variations in the lateral stratification of the WSC and variations with depth over shorter vertical distances. This information can be applied in sampling strategies, environmental monitoring, long-range transport of pollutants and physical oceanography

  17. Enhancement of biological mass spectrometry by using separations based on changes in ion mobility (FAIMS and DMS).

    Science.gov (United States)

    Purves, Randy W

    2013-01-01

    Analysis of complex biological samples for low-level analytes by liquid chromatography-tandem mass spectrometry (LC-MS/MS) often requires additional selectivity. Differential mobility techniques (FAIMS and DMS) have been shown to enhance LC-MS/MS analyses by separating ions in the gas-phase on a millisecond timescale by use of a mechanism that is complementary to both liquid chromatography and mass spectrometry. In this overview, a simplified description of the operation of these devices is given and an example presented that illustrates the utility of FAIMS (DMS) for solving a challenging analytical assay. Important recent advances in the field, including work with gas modifiers, are presented, along with an outlook for the technology.

  18. Neodymium isotopic variations in seawater

    International Nuclear Information System (INIS)

    Piepgras, D.J.; Wasserburg, G.J.

    1980-01-01

    New data for the direct measurement of the isotopic composition of neodymium in Atlantic Ocean seawater are compared with previous measurements of Pacific Ocean seawater and ferromanganese sediments from major ocean basins. Data for Atlantic seawater are in excellent agreement with Nd isotopic measurements made on Atlantic ferromanganese sediments and are distinctly different from the observed compositions of Pacific samples. These results clearly demonstrate the existence of distinctive differences in the isotopic composition of Nd in the waters of the major ocean basins and are characteristic of the ocean basin sampled. The average epsilonsub(N)sub(d)(0) values for the major oceans as determined by data from seawater and ferromanganese sediments are as follows: Atlantic Ocean, epsilonsub(N)sub(d)(0) approx. equal to - 12 +- 2; Indian Ocean, epsilonsub(N)sub(d)(0) approx. equal to - 8 +- 2; Pacific Ocean, epsilonsub(N)sub(d)(0) approx. equal to -3 +- 2. These values are considerably less than epsilonsub(N)sub(d)(0) value sources with oceanic mantle affinities indicating that the REE in the oceans are dominated by continental sources. The difference in the absolute abundance of 143 Nd between the Pacific and Atlantic Oceans corresponds to approx. 10 6 atoms 143 Nd per gram of seawater. The correspondence between the 143 Nd/ 144 Nd in seawater and in the associated sediments suggests the possible application of this approach to paleo-oceanography. (orig./HAE)

  19. Formation pathways of DMSO from DMS-OH in the presence of O(2) and NO(x): A theoretical study.

    Science.gov (United States)

    Ramírez-Anguita, Juan M; González-Lafont, Angels; Lluch, José M

    2009-01-30

    The relative importance of the reaction pathways and thus the product yields in the dimethyl sulfide (DMS) degradation scheme initiated by the hydroxyl (OH) radical has been said to be influenced by the content of nitrogen oxides (NO(x)) in chamber experiments. In this study, ab initio and density functional electronic structure calculations of all the possible reaction pathways corresponding to the reaction process initiated by DMS-OH + oxygen (O(2)), leading to the formation of the dimethyl sulfoxide (DMSO) product in the presence of NO(x) (NO and NO(2)), are carried out for the first time. The results for the different pathways are compared with the objective of inferring their kinetic relevance in the laboratory experiments that measure DMSO formation yields. Our theoretical results clearly show the existence of NO(x)-dependent pathways leading to the formation of DMSO in addition to O(2)-dependent channels. So then, NO(x)-containing conditions would have to modify the relative importance of the addition channel in the DMS oxidation process. (c) 2008 Wiley Periodicals, Inc.

  20. Recovery of uranium from seawater

    International Nuclear Information System (INIS)

    Hirotsu, Takahiro; Takagi, Norio; Katoh, Shunsaku

    1995-01-01

    Present status of the development of chelating adsorbents for the recovery of uranium from seawater is outlined with emphasis on the research by the author. Uranium is estimated to exist as stable tri (carbonate) uranylate (6) ion in seawater in a very low concentration. The adsorbent for uranium from seawater in a very low concentration. The adsorbent for uranium from seawater should have high selectivity and affinity for uranium around pH 8. The required characteristics for uranium adsorbent are examined. Various chelating adsorbents have been proposed for the uranium adsorbent and their structures are discussed. Amidoxime type adsorbents have the highest adsorbing power for uranium among the adsorbents hitherto developed and fibrous amidoxime adsorbents are most promising for the practical application. Synthesis, structure and suitable shape of the amidoxime adsorbents are discussed. Uranium adsorption behavior and the amount of saturated adsorption are examined theoretically based on the complexation of an amidoxime monomer and the formula for the adsorption equiliburium is derived. The adsorption and recovery process for uranium from seawater is composed of adsorption, desorption, separation and concentration and finally, uranium is recovered as the yellow cake. A floating body mooring system is proposed by Nobukawa. (T.H.)

  1. Evaluations of in vitro metabolism, drug-drug interactions mediated by reversible and time-dependent inhibition of CYPs, and plasma protein binding of MMB4 DMS.

    Science.gov (United States)

    Hong, S Peter; Lusiak, Bozena D; Burback, Brian L; Johnson, Jerry D

    2013-01-01

    1,1'-Methylenebis[4-[(hydroxyimino)methyl]-pyridinium] (MMB4) dimethanesulfonate (DMS) is a bisquaternary pyridinium aldoxime that reactivates acetylcholinesterase inhibited by organophosphorus nerve agent. Drug metabolism and plasma protein binding for MMB4 DMS were examined using various techniques and a wide range of species. When (14)C-MMB4 DMS was incubated in liver microsomes, 4-pyridine aldoxime (4-PA) and an additional metabolite were detected in all species tested. Identity of the additional metabolite was postulated to be isonicotinic acid (INA) based on liquid chromatography with a tandem mass spectrometry analysis, which was confirmed by comparison with authentic INA. Formation of INA was dependent on species, with the highest level found in monkey liver microsomes. The MMB4 DMS exhibited reversible inhibition in a concentration-dependent manner toward cytochrome P450 1A2 (CYP1A2), CYP2C9, CYP2C19, CYP2D6, and CYP3A4 in human liver microsomes showing the highest inhibition for CYP2D6. Human recombinant CYPs were used to evaluate inhibitory curves more adequately and determine detailed kinetic constants for reversible inhibition and potential time-dependent inhibition (TDI). The MMB4 DMS exhibited reversible inhibition toward human-recombinant CYP2D6 with an inhibition constant (K i) value of 66.6 µmol/L. Based on the k inact/K I values, MMB4 DMS was found to exhibit the most potent TDI toward CYP2D6. The MMB4 DMS at 5 different concentrations was incubated in plasma for 5 hours using an equilibrium dialysis device. For all species tested, there were no concentration-dependent changes in plasma protein binding, ranging from 10% to 17%. These results suggest that MMB4 was not extensively bound to plasma protein, and there were no overt species-related differences in the extent of MMB4 bound to plasma protein.

  2. Production and consumption of dimethylsulfide (DMS) and dimethylsulfoniopropionate (DMSP) in a diatom dominated intertidal sediment

    NARCIS (Netherlands)

    Van Bergeijk, S.A.; Schönefeldt, K.; Stal, L.J.; Huisman, J.

    2002-01-01

    Intertidal sediments usually contain a high amount of dimethylsulfoniopropionate (DMSP) and therefore represent environments with a potentially high emission of dimethylsulfide (DMS). However, knowledge on production and release of DMSP in intertidal sediments is limited. Here, we present data on

  3. Sampling problems and the determination of mercury in surface water, seawater, and air

    International Nuclear Information System (INIS)

    Das, H.A.; van der Sloot, H.A.

    1976-01-01

    Analysis of surface water for mercury comprises the determination of both ionic and organically bound mercury in solution and that of the total mercury content of the suspended matter. Eventually, metallic mercury has to be determined too. Requirements for the sampling procedure are given. A method for the routine determination of mercury in surface water and seawater was developed and applied to Dutch surface waters. The total sample volume is 2500 ml. About 500 ml is used for the determination of the content of suspended matter and the total amount of mercury in the water. The sample is filtered through a bed of previously purified active charcoal at a low flow-rate. The main portion ca. 2000 ml) passes a flow-through centrifuge to separate the solid fraction. One liter is used to separate ''inorganic'' mercury by reduction, volatilization in an airstream and adsorption on active charcoal. The other liter is led through a column of active charcoal to collect all mercury. The procedures were checked with 197 Hg radiotracer both as an ion and incorporated in organic compounds. The mercury is determined by thermal neutron activation, followed by volatilization in a tube furnace and adsorption on a fresh carbon bed. The limit of determination is approximately equal to 1 ng 1 -1 . The rate of desorption from and adsorption on suspended material has been measured as a function of a pH of the solution for Hg +2 and various other ions. It can be concluded that only the procedure mentioned above does not disturb the equilibrium. The separation of mercury from air is obtained by suction of 1 m 3 through a 0.22 μm filter and a charcoal bed. The determination is then performed as in the case of the water samples

  4. Study on stability of DMS meridian detector.

    Science.gov (United States)

    Yang, Ning; Huang, Li; Yuan, Jiamin; Zhang, Zhifang; Yang, Zhimin

    2016-05-01

    The stability of meridian detector was the basis to study meridian through conductance method. Ancient documents mentioned that the human body's blood could change with the time and meridians. When qi and blood came, the qi and blood would be full of that place; when qi and blood gone, the local skin shining could fade and recess. It liked the tidal fluctuation, then caused the corresponding acupuncture points conductance value changes. Modern studies had reported that meridian detector instrument the skin area of twelve meridians acupuncture points could change along with time within 24 hours. In this circumstance, whether the conductance values changes in human acupuncture points had statistical significance was vital important. DMS meridian detector instruction was adopt to measure the twelve meridian jingyuan acupuncture point in order to analyze the acupuncture point conductance value changes within one day.

  5. Preface: Special Issue of the 5th International Symposium on Biological and Environmental Chemistry of DMS(P) and Related Compounds, Goa, India, 19–22 October 2010

    Digital Repository Service at National Institute of Oceanography (India)

    Stefels, J.; Shenoy, D.M.; Simo, R.; Malin, G.; Levasseur, M.; Belviso, S.; DileepKumar, M.

    variation in bacteria- mediated DMSP(d) to DMS conversion, as a function of nutrient limitation. Aeolian delivery of soluble iron that exhibits considerable spatio-temporal variability (Srinivas et al.) can also influence DMS production in iron- limited...

  6. Absorption, distribution, metabolism, and excretion of 14C-MMB4 DMS administered intramuscularly to Sprague-Dawley rats and New Zealand White rabbits.

    Science.gov (United States)

    Lusiak, Bozena D; Kobs, Dean J; Hong, S Peter; Burback, Brian L; Johnson, Jerry D

    2013-01-01

    1,1'-Methylenebis[4-[(hydroxyimino)methyl]-pyridinium] dimethanesulfonate (MMB4 DMS) is currently under development for the treatment of chemical warfare organophosphorus nerve agent poisoning. The present study evaluates the absorption, distribution, metabolism, and excretion of (14)C-MMB4 DMS administered intramuscularly to rats and rabbits. The formulated mixture of radiolabeled and nonradiolabeled MMB4 DMS was administered as a single or 7-day repeated dose. Rat doses were 55 or 220 mg/kg (100 µCi/kg), and rabbit doses were 25 or 100 mg/kg (31.25 and 62.5 µCi/kg, respectively). Urine, bile (rats only), feces, blood, and tissues were collected for up to 72 hours. Metabolic profiling using high-performance liquid chromatography with radiodetection was performed on selected urine samples. For both animal species, the majority of the total radioactivity was excreted in the urine (74%-94%) by 72 hours after dosing with greater than 90% of the radioactivity measured in the urine within 8 to 12 hours after dosing. There were no apparent species or dose differences in the urine excretion pattern. The distribution of (14)C-MMB4 DMS-derived radioactivity was rapid and generally reached the highest concentration by the first collection time point (0.25 hours). The tissue-blood concentration ratios were highest at the injection sites and in the kidneys and gastrointestinal tract contents for both the species. Two metabolites of MMB4 DMS were detected in rat and rabbit urine; their structure was confirmed by liquid chromatography with tandem mass spectrometry as 4-pyridine aldoxime and isonicotinic acid (pyridine-4-carboxylic acid).

  7. Optimal scheduling of biocide dosing for seawater-cooled power and desalination plants

    KAUST Repository

    Mahfouz, Abdullah Bin

    2011-02-13

    Thermal desalination systems are typically integrated with power plants to exploit the excess heat resulting from the power-generation units. Using seawater in cooling the power plant and the desalination system is a common practice in many parts of the world where there is a shortage of freshwater. Biofouling is one of the major problems associated with the usage of seawater in cooling systems. Because of the dynamic variation in the power and water demands as well as the changes in the characteristics of seawater and the process, there is a need to develop an optimal policy for scheduling biocide usage and cleaning maintenance of the heat exchangers. The objective of this article is to introduce a systematic procedure for the optimization of scheduling the dosing of biocide and dechlorination chemicals as well as cleaning maintenance for a power production/thermal desalination plant. A multi-period optimization formulation is developed and solved to determine: the optimal levels of dosing and dechlorination chemicals; the timing of maintenance to clean the heat-exchange surfaces; and the dynamic dependence of the biofilm growth on the applied doses, the seawater-biocide chemistry, the process conditions, and seawater characteristics for each time period. The technical, economic, and environmental considerations of the system are accounted for. A case study is solved to elucidate the applicability of the developed optimization approach. © 2011 Springer-Verlag.

  8. Aragonite coating solutions (ACS) based on artificial seawater

    International Nuclear Information System (INIS)

    Tas, A. Cuneyt

    2015-01-01

    Graphical abstract: - Highlights: • Developed completely inorganic solutions for the deposition of monolayers of aragonite spherules (or ooids). • Solutions mimicked the artificial seawater. • Biomimetic crystallization was performed at the tropical sea surface temperature of 30 °C. - Abstract: Aragonite (CaCO 3 , calcium carbonate) is an abundant biomaterial of marine life. It is the dominant inorganic phase of coral reefs, mollusc bivalve shells and the stalactites or stalagmites of geological sediments. Inorganic and initially precipitate-free aragonite coating solutions (ACS) of pH 7.4 were developed in this study to deposit monolayers of aragonite spherules or ooids on biomaterial (e.g., UHMWPE, ultrahigh molecular weight polyethylene) surfaces soaked in ACS at 30 °C. The ACS solutions of this study have been developed for the surface engineering of synthetic biomaterials. The abiotic ACS solutions, enriched with calcium and bicarbonate ions at different concentrations, essentially mimicked the artificial seawater composition and started to deposit aragonite after a long (4 h) incubation period at the tropical sea surface temperature of 30 °C. While numerous techniques for the solution deposition of calcium hydroxyapatite (Ca 10 (PO 4 ) 6 (OH) 2 ), of low thermodynamic solubility, on synthetic biomaterials have been demonstrated, procedures related to the solution-based surface deposition of high solubility aragonite remained uncommon. Monolayers of aragonite ooids deposited at 30 °C on UHMWPE substrates soaked in organic-free ACS solutions were found to possess nano-structures similar to the mortar-and-brick-type botryoids observed in biogenic marine shells. Samples were characterized using SEM, XRD, FTIR, ICP-AES and contact angle goniometry

  9. Aragonite coating solutions (ACS) based on artificial seawater

    Energy Technology Data Exchange (ETDEWEB)

    Tas, A. Cuneyt, E-mail: c_tas@hotmail.com

    2015-03-01

    Graphical abstract: - Highlights: • Developed completely inorganic solutions for the deposition of monolayers of aragonite spherules (or ooids). • Solutions mimicked the artificial seawater. • Biomimetic crystallization was performed at the tropical sea surface temperature of 30 °C. - Abstract: Aragonite (CaCO{sub 3}, calcium carbonate) is an abundant biomaterial of marine life. It is the dominant inorganic phase of coral reefs, mollusc bivalve shells and the stalactites or stalagmites of geological sediments. Inorganic and initially precipitate-free aragonite coating solutions (ACS) of pH 7.4 were developed in this study to deposit monolayers of aragonite spherules or ooids on biomaterial (e.g., UHMWPE, ultrahigh molecular weight polyethylene) surfaces soaked in ACS at 30 °C. The ACS solutions of this study have been developed for the surface engineering of synthetic biomaterials. The abiotic ACS solutions, enriched with calcium and bicarbonate ions at different concentrations, essentially mimicked the artificial seawater composition and started to deposit aragonite after a long (4 h) incubation period at the tropical sea surface temperature of 30 °C. While numerous techniques for the solution deposition of calcium hydroxyapatite (Ca{sub 10}(PO{sub 4}){sub 6}(OH){sub 2}), of low thermodynamic solubility, on synthetic biomaterials have been demonstrated, procedures related to the solution-based surface deposition of high solubility aragonite remained uncommon. Monolayers of aragonite ooids deposited at 30 °C on UHMWPE substrates soaked in organic-free ACS solutions were found to possess nano-structures similar to the mortar-and-brick-type botryoids observed in biogenic marine shells. Samples were characterized using SEM, XRD, FTIR, ICP-AES and contact angle goniometry.

  10. Rapid determination of actinides in seawater samples

    International Nuclear Information System (INIS)

    Maxwell, S.L.; Culligan, B.K.; Hutchison, J.B.; Utsey, R.C.; McAlister, D.R.

    2014-01-01

    A new rapid method for the determination of actinides in seawater samples has been developed at the Savannah River National Laboratory. The actinides can be measured by alpha spectrometry or inductively-coupled plasma mass spectrometry. The new method employs novel pre-concentration steps to collect the actinide isotopes quickly from 80 L or more of seawater. Actinides are co-precipitated using an iron hydroxide co-precipitation step enhanced with Ti +3 reductant, followed by lanthanum fluoride co-precipitation. Stacked TEVA Resin and TRU Resin cartridges are used to rapidly separate Pu, U, and Np isotopes from seawater samples. TEVA Resin and DGA Resin were used to separate and measure Pu, Am and Cm isotopes in seawater volumes up to 80 L. This robust method is ideal for emergency seawater samples following a radiological incident. It can also be used, however, for the routine analysis of seawater samples for oceanographic studies to enhance efficiency and productivity. In contrast, many current methods to determine actinides in seawater can take 1-2 weeks and provide chemical yields of ∼30-60 %. This new sample preparation method can be performed in 4-8 h with tracer yields of ∼85-95 %. By employing a rapid, robust sample preparation method with high chemical yields, less seawater is needed to achieve lower or comparable detection limits for actinide isotopes with less time and effort. (author)

  11. Colloidal nature of radionuclides in seawater

    International Nuclear Information System (INIS)

    Feldman, I.

    1976-01-01

    There is considerable doubt that equilibrium calculations, i.e., employing solubility products and complex-ion stability constants, are valid for the submicro concentrations of radionuclides in seawater. The existence of radiocolloids should be expected in seawater. The great tendency of radiocolloids to adsorb onto finely-divided hydrous oxides makes their formation of significance in seawater, especially for artificial radionuclides. The subject of radiocolloid formation is reviewed in this chapter. It is shown that the 226 Ra/ 230 Th/U relationship found in seawater can be explained from the fact that the tendencies of these elements to form radiocolloids in seawater should decrease in order thorium > radium much greater than uranium. This explanation is much simpler than the prevailing oceanographic one. The theories for radiocolloid formation are discussed. The recent theory of Jones and Healy for the adsorption of hydrolyzable metal ions onto hydrous oxides is reviewed briefly, and its relevance to radiocolloid formation is pointed out

  12. Surface chemical characteristics of coal fly ash particles after interaction with seawater under natural deep sea conditions

    International Nuclear Information System (INIS)

    Brami, Y.; Shemesh, A.; Cohen, H.; Herut, B.

    1999-01-01

    The surface chemical characteristics of coal fly ash (CFA) before and after interaction with Mediterranean deep seawater was studied by X-ray photoelectron spectroscopy (XPS). Significantly lower values of Si, Ca, and S and higher values of Mg and Cl were found in the retrieved CFA as compared to fresh CFA. It is suggested that hydrolysis of the oxide matrixes results in an alkaline environment which rapidly leads to several chemical reactions. The two most important are (a) dissolution of the amorphous silicate and the calcium phases and (b) precipitation of Mg(OH) 2 -brucite. A depth profile of the retrieved CFA was measured by both line-shape analysis of the XPS spectra and by consecutive cycle of sputtering. The thickness of the brucite layer is estimated to be 1.3 nm

  13. Extraction of uranium from seawater: evaluation of uranium resources and plant siting

    International Nuclear Information System (INIS)

    Rodman, M.R.; Gordon, L.I.; Chen, A.C.T.

    1979-02-01

    This report deals with the evaluation of U.S. coastal waters as a uranium resource and with the selection of a suitable site for construction of a large-scale plant for uranium extraction. Evaluation of the resource revealed that although the concentration of uranium is quite low, about 3.3 ppB in seawater of average oceanic salinity, the amount present in the total volume of the oceans is very great, some 4.5 billion metric tons. Of this, perhaps only that uranium contained in the upper 100 meters or so of the surface well-mixed layer should be considered accessible for recovery, some 160 million tonnes. The study indicated that open ocean seawater acquired for the purpose of uranium extraction would be a more favorable resource than rivers entering the sea, cooling water of power plants, or the feed or effluent streams of existing plants producing other products such as magnesium, bromine, or potable and/or agricultural water from seawater. Various considerations led to the selection of a site for a pumped seawater coastal plant at a coastal location. Puerto Yabucoa, Puerto Rico was selected. Recommendations are given for further studies. 21 figures, 8 tables

  14. Extraction of uranium from seawater: evaluation of uranium resources and plant siting

    Energy Technology Data Exchange (ETDEWEB)

    Rodman, M.R.; Gordon, L.I.; Chen, A.C.T.

    1979-02-01

    This report deals with the evaluation of U.S. coastal waters as a uranium resource and with the selection of a suitable site for construction of a large-scale plant for uranium extraction. Evaluation of the resource revealed that although the concentration of uranium is quite low, about 3.3 ppB in seawater of average oceanic salinity, the amount present in the total volume of the oceans is very great, some 4.5 billion metric tons. Of this, perhaps only that uranium contained in the upper 100 meters or so of the surface well-mixed layer should be considered accessible for recovery, some 160 million tonnes. The study indicated that open ocean seawater acquired for the purpose of uranium extraction would be a more favorable resource than rivers entering the sea, cooling water of power plants, or the feed or effluent streams of existing plants producing other products such as magnesium, bromine, or potable and/or agricultural water from seawater. Various considerations led to the selection of a site for a pumped seawater coastal plant at a coastal location. Puerto Yabucoa, Puerto Rico was selected. Recommendations are given for further studies. 21 figures, 8 tables.

  15. Exploring travelers' behavior in response to dynamic message signs (DMS) using a driving simulator : final report.

    Science.gov (United States)

    2013-10-01

    This research studies the effectiveness of a dynamic message sign (DMS) using a driving : simulator. Over 100 subjects from different socio-economic and age groups were recruited to : drive the simulator under different traffic and driving conditions...

  16. Leaching behavior of gamma-emitting fission products and Np from neutron-irradiated UO_2-ZrO_2 solid solutions in non-filtered surface seawater

    International Nuclear Information System (INIS)

    Sasaki, Takayuki; Takeno, Yuu; Kobayashi, Taishi; Kirishima, Akira; Sato, Nobuaki

    2016-01-01

    The gamma ray radionuclides Cs-137, Ba-140, I-131, Ce-141, Ru-103, Zr-95, and Np-239 were produced by neutron irradiation of UO_2-ZrO_2 solid solutions that were synthesized as simulated fuel debris under reducing and oxidizing conditions. The leaching ratio of radionuclides was investigated under atmospheric conditions at 25°C for non-filtered natural surface seawater, as well as deionized water after filtration with a membrane of 0.45-μm pore size or that of nominal molecular weight limit of 3 kDa. The uranium molar concentration was affected by the oxidation state in the solid solution samples. The congruent dissolution of Cs, I, and Ba with the hexavalent uranium of U_3O_8 was facilitated in the seawater samples, whereas a lower leaching ratio of nuclides was observed in the deionized water samples. Neptunium-239, originally produced from uranium-238 in U_3O_8, showed behavior that was similar to that of Cs, I, and Ba. However, the dissolution of Np (as a parent nuclide of Pu-239) in the debris of UO_2 and UO_2-ZrO_2 was suppressed in the same manner as Zr(IV) and Ce(IV). The concentration exhibited no filtration dependence after 15 d, which shows that most of the leached nuclides can exist in their ionic form in seawater. (author)

  17. Effect of different seawater Mg

    NARCIS (Netherlands)

    Mewes, A.; Langer, G.; de Nooijer, L.J.; Bijma, J.; Reichart, G.J.

    2014-01-01

    Magnesium, incorporated in foraminiferal calcite (Mg/CaCC), is used intensively to reconstruct past seawater temperatures but, in addition to temperature, the Mg/CaCC of foraminiferal tests also depends on the ratio of Mg and Ca in seawater (Mg/CaSW). The physiological mechanisms responsible for

  18. Microbial Degradation Behavior in Seawater of Polyester Blends Containing Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate (PHBHHx

    Directory of Open Access Journals (Sweden)

    Hitoshi Sashiwa

    2018-01-01

    Full Text Available The microbial degradation behavior of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate (PHBHHx and its compound with several polyesters such as poly(butylene adipate-co-telephtharate (PBAT, poly(butylene succinate (PBS, and polylactic acid (PLA in seawater was tested by a biological oxygen demand (BOD method. PHBHHx showed excellent biodegradation in seawater in this study. In addition, the biodegradation rate of several blends was much influenced by the weight ratio of PHBHHx in their blends and decreased in accordance with the decrement of PHBHHX ratio. The surface morphology of the sheet was important factor for controlling the biodegradation rate of PHBHHx-containing blends in seawater.

  19. Electrochemical evaluation of the influence of pseudomonas sp on aluminium brass in seawater

    International Nuclear Information System (INIS)

    Frontini, Maria Alejandra; Rosso de Sanchez, Susana

    2004-01-01

    The development of a biofilm on metallic surfaces generates serious problems for the acceleration of corrosive processes. The control of the development of the biological film is important because its formation, among other effects, causes fouling of the surface where it has developed, producing differential aeration cells and aggressive metabolites. The influence of surface films was studied by applying electrochemical techniques in artificial seawater with and without bacteria, under different immersion times. Since the pitting potential (Epic) defines the metals' ability to resist pitting corrosion, a measure of susceptibility to pitting in aggressive solutions is considered. The pitting potential was studied in the systems being studied as well as the influence of seawater + ClO - ion biocides on the systems, since the biocides used was sodium hypochlorite (NaCIO). The material used was aluminum brass and a wild bacterial strain was used, which was isolated from the tubes by a heat exchanger from a thermoelectric plant (CW)

  20. Estimates of ikaite export from sea ice to the underlying seawater in a sea ice-seawater mesocosm

    Science.gov (United States)

    Geilfus, Nicolas-Xavier; Galley, Ryan J.; Else, Brent G. T.; Campbell, Karley; Papakyriakou, Tim; Crabeck, Odile; Lemes, Marcos; Delille, Bruno; Rysgaard, Søren

    2016-09-01

    The precipitation of ikaite and its fate within sea ice is still poorly understood. We quantify temporal inorganic carbon dynamics in sea ice from initial formation to its melt in a sea ice-seawater mesocosm pool from 11 to 29 January 2013. Based on measurements of total alkalinity (TA) and total dissolved inorganic carbon (TCO2), the main processes affecting inorganic carbon dynamics within sea ice were ikaite precipitation and CO2 exchange with the atmosphere. In the underlying seawater, the dissolution of ikaite was the main process affecting inorganic carbon dynamics. Sea ice acted as an active layer, releasing CO2 to the atmosphere during the growth phase, taking up CO2 as it melted and exporting both ikaite and TCO2 into the underlying seawater during the whole experiment. Ikaite precipitation of up to 167 µmol kg-1 within sea ice was estimated, while its export and dissolution into the underlying seawater was responsible for a TA increase of 64-66 µmol kg-1 in the water column. The export of TCO2 from sea ice to the water column increased the underlying seawater TCO2 by 43.5 µmol kg-1, suggesting that almost all of the TCO2 that left the sea ice was exported to the underlying seawater. The export of ikaite from the ice to the underlying seawater was associated with brine rejection during sea ice growth, increased vertical connectivity in sea ice due to the upward percolation of seawater and meltwater flushing during sea ice melt. Based on the change in TA in the water column around the onset of sea ice melt, more than half of the total ikaite precipitated in the ice during sea ice growth was still contained in the ice when the sea ice began to melt. Ikaite crystal dissolution in the water column kept the seawater pCO2 undersaturated with respect to the atmosphere in spite of increased salinity, TA and TCO2 associated with sea ice growth. Results indicate that ikaite export from sea ice and its dissolution in the underlying seawater can potentially hamper

  1. Rapid and gradual modes of aerosol trace metal dissolution in seawater

    Directory of Open Access Journals (Sweden)

    Katherine Rose Marie Mackey

    2015-01-01

    Full Text Available Atmospheric deposition is a major source of trace metals in marine surface waters and supplies vital micronutrients to phytoplankton, yet measured aerosol trace metal solubility values are operationally defined and there are relatively few multi-element studies on aerosol-metal solubility in seawater. Here we measure the solubility of aluminum (Al, cadmium (Cd, cobalt (Co, copper (Cu, iron (Fe, manganese (Mn, nickel (Ni, lead (Pb, and zinc (Zn from natural aerosol samples in seawater over a 7 day period to (1 evaluate the role of extraction time in trace metal dissolution behavior and (2 explore how the individual dissolution patterns could influence biota. Dissolution behavior occurs over a continuum ranging from rapid dissolution, in which the majority of soluble metal dissolved immediately upon seawater exposure (Cd and Co in our samples, to gradual dissolution, where metals dissolved slowly over time (Zn, Mn, Cu, and Al in our samples. Additionally, dissolution affected by interactions with particles was observed in which a decline in soluble metal concentration over time occurred (Fe and Pb in our samples. Natural variability in aerosol chemistry between samples can cause metals to display different dissolution kinetics in different samples, and this was particularly evident for Ni, for which samples showed a broad range of dissolution rates. The elemental molar ratio of metals in the bulk aerosols was 23,189Fe: 22,651Al: 445Mn: 348Zn: 71Cu: 48Ni: 23Pb: 9Co: 1Cd, whereas the seawater soluble molar ratio after 7 days of leaching was 11Fe: 620Al: 205Mn: 240Zn: 20Cu: 14Ni: 9Pb: 2Co: 1Cd. The different kinetics and ratios of aerosol metal dissolution have implications for phytoplankton nutrition, and highlight the need for unified extraction protocols that simulate aerosol metal dissolution in the surface ocean.

  2. Physico-chemical behavior of radionuclides in seawater

    International Nuclear Information System (INIS)

    Kimura, Yuichiro; Ogawa, Yoshihiro; Honda, Yoshihide; Katsurayama, Kosuke.

    1980-01-01

    To elucidate the physico-chemical states of radionuclides in seawater in relation to uptake by the marine biosphere, the physicochemical behavior of radiocobalt, radioruthenium and radiocerium in seawater was investigated by electrodialysis, high-voltage paper electrophoresis, and also by paper chromatography for nitrosylruthenium complexes. Most of the radiocobalt in seawater behaved as dialytic cations. However, these cationic species were not necessarily simple divalent, because their electrophoretic bands were rather diffuse and showed two peaks temporarily. The electroneutral form also increased with aging in seawater. The radioruthenium in seawater showed relatively a number of well-defined species which could be readily classified into anionic, cationic, electroneutral, colloidal or particulate, non-dialytic and more or less adsorbable species. The radioruthenium in the chloro and nitratonitrosylruthenium complexes occurred mainly electroneutral and anionic species, while nitro and binuclear oxygen-bridged nitratonitrosylruthenium complexes showed dominant anionic species. The hydrolysis of higher nitro and nitratonitrosylruthenium complexes to lower ones was demonstrated with aging in seawater by paper chromatography. The radiocerium in seawater showed initially cationic species. However, the electroneutral and anionic species were revealed with aging by electrodialysis. The radiocerium were strongly adsorbed on filter paper at the starting band in paper electrophoresis, presumably because of the formation of strongly adsorbable or insoluble hydrolytic species or particle formation. (author)

  3. Facile Preparation of Porous WO3 Film for Photoelectrochemical Splitting of Natural Seawater

    Science.gov (United States)

    Shi, Yonghong; Li, Yuangang; Wei, Xiaoliang; Feng, Juan; Li, Huajing; Zhou, Wanyi

    2017-12-01

    Sunlight-driven natural seawater splitting provides a promising way for large-scale conversion and storage of solar energy. Here, we develop a facile and low-cost method via a deposition-annealing technique to fabricate porous WO3 film and demonstrate its application as a photoanode for natural seawater splitting. The WO3 film yields a photocurrent density of 1.95 mA cm-2 and possesses excellent stability at 1.23 V (versus RHE), under the illumination of 100 mW cm-2 (AM 1.5G). The photoelectrochemical performance is ascribed to the large surface area and good permeation of the electrolyte into the porous film. Furthermore, the photocurrent density remains almost the same during 3 h continuous light irradiation. The evolution of chlorine gas from seawater splitting was determined with qualitative and quantitative analyses, with a Faradic efficiency of about 56%.

  4. Seawater 234U/238U recorded by modern and fossil corals

    Science.gov (United States)

    Chutcharavan, Peter M.; Dutton, Andrea; Ellwood, Michael J.

    2018-03-01

    U-series dating of corals is a crucial tool for generating absolute chronologies of Late Quaternary sea-level change and calibrating the radiocarbon timescale. Unfortunately, coralline aragonite is susceptible to post-depositional alteration of its primary geochemistry. One screening technique used to identify unaltered corals relies on the back-calculation of initial 234U/238U activity (δ234Ui) at the time of coral growth and implicitly assumes that seawater δ234U has remained constant during the Late Quaternary. Here, we test this assumption using the most comprehensive compilation to date of coral U-series measurements. Unlike previous compilations, this study normalizes U-series measurements to the same decay constants and corrects for offsets in interlaboratory calibrations, thus reducing systematic biases between reported δ234U values. Using this approach, we reassess (a) the value of modern seawater δ234U, and (b) the evolution of seawater δ234U over the last deglaciation. Modern coral δ234U values (145.0 ± 1.5‰) agree with previous measurements of seawater and modern corals only once the data have been normalized. Additionally, fossil corals in the surface ocean display δ234Ui values that are ∼5-7‰ lower during the last glacial maximum regardless of site, taxon, or diagenetic setting. We conclude that physical weathering of U-bearing minerals exposed during ice sheet retreat drives the increase in δ234U observed in the oceans, a mechanism that is consistent with the interpretation of the seawater Pb-isotope signal over the same timescale.

  5. Progress in recovery technology for uranium from seawater

    International Nuclear Information System (INIS)

    Sugo, Takanobu; Saito, Kyoichi.

    1994-01-01

    By the facts that the research group in Japan improved the performance of amidoxime resin which is the adsorbent for collecting seawater uranium, proposed the method of mooring floating bodies utilizing sea current and waves as the adsorption system, and further, verified the results of laboratory basic experiment by marine experiment, the technology of collecting seawater uranium has progressed. After the oil crisis, various countries started the research on seawater uranium, but only Japan has continued the systematic study up to now. In this report, the research on seawater uranium collection carried out so far is summarized, and the characteristics of the adsorbent which was synthesized by radiation graft polymerization and the results of the uranium collection test using coastal seawater are reported. In seawater of 1 m 3 , the uranium of 3.3 mg is dissolved in the form of uranyl tricarbonate complex ions. In the total quantity of seawater, the dissolved uranium amounts to about 4.6 billion tons, about 1000 times of the uranium resources on land. The research on seawater uranium collection and the performance of uranium adsorption of synthesized amidoxime fibers are reported. (K.I.)

  6. Paleogene Seawater Osmium Isotope Records

    Science.gov (United States)

    Rolewicz, Z.; Thomas, D. J.; Marcantonio, F.

    2012-12-01

    Paleoceanographic reconstructions of the Late Cretaceous and early Cenozoic require enhanced geographic coverage, particularly in the Pacific, in order to better constrain meridional variations in environmental conditions. The challenge with the existing inventory of Pacific deep-sea cores is that they consist almost exclusively of pelagic clay with little existing age control. Pelagic clay sequences are useful for reconstructions of dust accumulation and water mass composition, but accurate correlation of these records to other sites requires improved age control. Recent work indicates that seawater Os isotope analyses provide useful age control for red clay sequences. The residence time of Os in seawater is relatively long compared to oceanic mixing, therefore the global seawater 187Os/188Os composition is practically homogeneous. A growing body of Late Cretaceous and Cenozoic data has constrained the evolution of the seawater Os isotopic composition and this curve is now a viable stratigraphic tool, employed in dating layers of Fe-Mn crusts (e.g., Klemm et al., 2005). Ravizza (2007) also demonstrated that the seawater Os isotopic composition can be extracted reliably from pelagic red clay sediments by analyzing the leached oxide minerals. The drawback to using seawater Os isotope stratigraphy to date Paleogene age sediments is that the compilation of existing data has some significant temporal gaps, notably between ~38 and 55 Ma. To improve the temporal resolution of the seawater Os isotope curve, we present new data from Ocean Drilling Program (ODP) Site 865 in the equatorial Pacific. Site 865 has excellent biostratigraphic age control over the interval ~38-55Ma. Preliminary data indicate an increase in the seawater composition from 0.427 at 53.4 Ma to 0.499 by 43 Ma, consistent with the apparent trend in the few existing data points. We also analyzed the Os isotopic composition recorded by oxide minerals at Integrated Ocean Drilling Program (IODP) Site U1370

  7. Spin-exciton interaction and related micro-photoluminescence spectra of ZnSe:Mn DMS nanoribbon.

    Science.gov (United States)

    Hou, Lipeng; Zhou, Weichang; Zou, Bingsuo; Zhang, Yu; Han, Junbo; Yang, Xinxin; Gong, Zhihong; Li, Jingbo; Xie, Sishen; Shi, Li-Jie

    2017-03-10

    For their spintronic applications the magnetic and optical properties of diluted magnetic semiconductors (DMS) have been studied widely. However, the exact relationships between the magnetic interactions and optical emission behaviors in DMS are not well understood yet due to their complicated microstructural and compositional characters from different growth and preparation techniques. Manganese (Mn) doped ZnSe nanoribbons with high quality were obtained by using the chemical vapor deposition (CVD) method. Successful Mn ion doping in a single ZnSe nanoribbon was identified by elemental energy-dispersive x-ray spectroscopy mapping and micro-photoluminescence (PL) mapping of intrinsic d-d optical transition at 580 nm, i.e. the transition of 4 T 1 ( 4 G) →  6 A 1 ( 6 s),. Besides the d-d transition PL peak at 580 nm, two other PL peaks related to Mn ion aggregates in the ZnSe lattice were detected at 664 nm and 530 nm, which were assigned to the d-d transitions from the Mn 2+ -Mn 2+ pairs with ferromagnetic (FM) coupling and antiferromagnetic (AFM) coupling, respectively. Moreover, AFM pair formation goes along with strong coupling with acoustic phonon or structural defects. These arguments were supported by temperature-dependent PL spectra, power-dependent PL lifetimes, and first-principle calculations. Due to the ferromagnetic pair existence, an exciton magnetic polaron (EMP) is formed and emits at 460 nm. Defect existence favors the AFM pair, which also can account for its giant enhancement of spin-orbital coupling and the spin Hall effect observed in PRL 97, 126603(2006) and PRL 96, 196404(2006). These emission results of DMS reflect their relation to local sp-d hybridization, spin-spin magnetic coupling, exciton-spin or phonon interactions covering structural relaxations. This kind of material can be used to study the exciton-spin interaction and may find applications in spin-related photonic devices besides spintronics.

  8. Impact of Seawater Nonlinearities on Nordic Seas Circulation

    Science.gov (United States)

    Helber, R. W.; Wallcraft, A. J.; Shriver, J. F.

    2017-12-01

    The Nordic Seas (Greenland, Iceland, and Norwegian Seas) form an ocean basin important for Arctic-mid-latitude climate linkages. Cold fresh water from the Arctic Ocean and warm salty water from the North Atlantic Ocean meet in the Nordic Seas, where a delicate balance between temperature and salinity variability results in deep water formation. Seawater non-linearities are stronger at low temperatures and salinities making high-latitude oceans highly subject to thermbaricity and cabbeling. This presentation highlights and quantifies the impact of seawater non-linearities on the Nordic Seas circulation. We use two layered ocean circulation models, the Hybrid Coordinate Ocean Model (HYOCM) and the Modular Ocean Model version 6 (MOM6), that enable accurate representation of processes along and across density or neutral density surfaces. Different equations-of-state and vertical coordinates are evaluated to clarify the impact of seawater non-linearities. Present Navy systems, however, do not capture some features in the Nrodic Seas vertical structure. For example, observations from the Greenland Sea reveal a subsurface temperature maximum that deepens from approximately 1500 m during 1998 to 1800 m during 2005. We demonstrate that in terms of density, salinity is the largest source of error in Nordic Seas Navy forecasts, regional scale models can represent mesoscale features driven by thermobaricity, vertical coordinates are a critical issue in Nordic Sea circulation modeling.

  9. Numerical Study of Groundwater Flow and Salinity Distribution Cycling Controlled by Seawater/Freshwater Interaction in Karst Aquifer Using SEAWAT

    Science.gov (United States)

    Xu, Z.; Hu, B.

    2017-12-01

    The interest to predict seawater intrusion and salinity distribution in Woodville Karst Plain (WKP) has increased due to the huge challenge on quality of drinkable water and serious environmental problems. Seawater intrudes into the conduit system from submarine karst caves at Spring Creek Spring due to density difference and sea level rising, nowadays the low salinity has been detected at Wakulla Spring which is 18 km from coastal line. The groundwater discharge at two major springs and salinity distribution in this area is controlled by the seawater/freshwater interaction under different rainfall conditions: during low rainfall periods, seawater flow into the submarine spring through karst windows, then the salinity rising at the submarine spring leads to seawater further intrudes into conduit system; during high rainfall periods, seawater is pushed out by fresh water discharge at submarine spring. The previous numerical studies of WKP mainly focused on the density independent transport modeling and seawater/freshwater discharge at major karst springs, in this study, a SEAWAT model has been developed to fully investigate the salinity distribution in the WKP under repeating phases of low rainfall and high rainfall periods, the conduit system was simulated as porous media with high conductivity and porosity. The precipitation, salinity and discharge at springs were used to calibrate the model. The results showed that the salinity distribution in porous media and conduit system is controlled by the rainfall change, in general, the salinity distribution inland under low rainfall conditions is much higher and wider than the high rainfall conditions. The results propose a prediction on the environmental problem caused by seawater intrusion in karst coastal aquifer, in addition, provide a visual and scientific basis for future groundwater remediation.

  10. Impregnation/Agglomeration Laboratory Tests of Heavy Fuel from Prestige to Improve Its Manageability and Removal from Seawater Surface. (Physical Behaviour of Fuel Agglomates)

    International Nuclear Information System (INIS)

    Garcia Frutos, F. J.; Rodriguez, V.; Otero, J.

    2002-01-01

    The handling and removal problems showed by heavy fuel floating in seawater could be improved or solved by using materials that agglomerate it. These materials must fulfill the following conditions: be inert materials in marine environment, the agglomerated fuel/material should float and its application and removal should be done using simple technologies. Based on these requirements, clay minerals, pine chips, mineral coal and charcoal were selected. The preliminary/results on impregnation/agglomeration with the materials mentioned above of heavy fuel from Prestige at lab scale are presented in this paper. The results have shown that only hydrophobic materials, such as mineral coal and charcoal, are able to agglomerate with fuel, which is also a hydrophobic substance. Whereas the agglomerates fuel/mineral coal sink, the agglomerates fuel/charcoal keep floating on water surface. It can be concluded that the addition of charcoal on dispersed fuel in seawater could improve its handling and removal. In this sense, pilot scale and eventually controlled in situ tests to study the feasibility of the proposed solution should be performed. (Author) 2 refs

  11. Boron Removal from Seawater by Thin-Film Composite Reverse Osmosis Membranes

    KAUST Repository

    Al Sunbul, Yasmeen

    2018-04-01

    Reverse Osmosis membranes have been successfully proven to remove almost 99% of chemicals dissolved in seawater. However, removal of certain trace elements, such as boron is challenging and relatively low for seawater reverse osmosis desalination plants compared to thermal desalination plants. Boron is naturally occurring and is present in seawater at an average concentration of 4.5-5 mg/L. While boron is a vital element, its toxicity has been proven on crops, animals and possibly humans. Additionally, boron should be removed to comply with the current guideline value of 0.5 mg/L, for drinking water, issued by the World Health Organization (WHO), which is barely attained by a single-pass process seawater reverse osmosis plant. Currently, multipass reverse osmosis membrane operations with pH modifications are the only valid method for boron removal. However, this is not economically efficient as it requires higher energy and chemicals consumptions. The objective of this study was to investigate boron removal by commercial TFC RO membranes in addition to custom-made KAUST-synthesized TFC membrane. Five membrane samples were examined: Toray, Sepro, Koch, and KAUST in-house synthesized membrane. Three different feed pH conditions were used: pH6, pH8, and pH10. Filtration experiments were conducted in two parts. In experiment 1, all five membranes were examined for boron rejection in a dead-end permeation system, whereas in experiment 2 the two membranes with the highest boron rejection from experiment 1 were tested in a cross-flow system. Permeate and feed samples were taken continuously and analyzed for boron concentration, rejection calculation. Membrane surfaces were characterized according to hydrophilicity, roughness and surface charge. The results showed for all the tested membranes that boron rejection increased as the feed pH increased. KAUST, defect-free TFC, showed the highest performance for boron rejection for all pH conditions, although, it shows the

  12. Branchial ionocyte organization and ion-transport protein expression in juvenile alewives acclimated to freshwater or seawater

    Science.gov (United States)

    Christensen, A.K.; Hiroi, J.; Schultz, E.T.; McCormick, S.D.

    2012-01-01

    The alewife (Alosa pseudoharengus) is a clupeid that undergoes larval and juvenile development in freshwater preceding marine habitation. The purpose of this study was to investigate osmoregulatory mechanisms in alewives that permit homeostasis in different salinities. To this end, we measured physiological, branchial biochemical and cellular responses in juvenile alewives acclimated to freshwater (0.5p.p.t.) or seawater (35.0p.p.t.). Plasma chloride concentration was higher in seawater-acclimated than freshwater-acclimated individuals (141mmoll -1 vs 134mmoll -1), but the hematocrit remained unchanged. In seawateracclimated individuals, branchial Na +/K +-ATPase (NKA) activity was higher by 75%. Western blot analysis indicated that the abundance of the NKA subunit and a Na+/K+/2Cl- cotransporter (NKCC1) were greater in seawater-acclimated individuals by 40% and 200%, respectively. NKA and NKCC1 were localized on the basolateral surface and tubular network of ionocytes in both acclimation groups. Immunohistochemical labeling for the cystic fibrosis transmembrane conductance regulator (CFTR) was restricted to the apical crypt of ionocytes in seawater-acclimated individuals, whereas sodium/hydrogen exchanger 3 (NHE3) labeling was present on the apical surface of ionocytes in both acclimation groups. Ionocytes were concentrated on the trailing edge of the gill filament, evenly distributed along the proximal 75% of the filamental axis and reduced distally. Ionocyte size and number on the gill filament were not affected by salinity; however, the number of lamellar ionocytes was significantly lower in seawater-acclimated fish. Confocal z-series reconstructions revealed that mature ionocytes in seawater-acclimated alewives occurred in multicellular complexes. These complexes might reduce paracellular Na + resistance, hence facilitating Na+ extrusion in hypo-osmoregulating juvenile alewives after seaward migration. ?? 2012. Published by The Company of Biologists Ltd.

  13. Determination of picomolar beryllium levels in seawater with inductively coupled plasma mass spectrometry following silica-gel preconcentration

    Energy Technology Data Exchange (ETDEWEB)

    Tazoe, Hirofumi, E-mail: tazoe@cc.hirosaki-u.ac.jp [Department of Radiation Chemistry, Institute of Radiation Emergency Mediation, Hirosaki University, 66-1 Hon-cho, Hirosaki, Aomori 036-8564 (Japan); College of Humanities and Sciences, Nihon University, 3-25-40, Sakurajosui, Setagaya-ku, Tokyo 156-8550 (Japan); Yamagata, Takeyasu [College of Humanities and Sciences, Nihon University, 3-25-40, Sakurajosui, Setagaya-ku, Tokyo 156-8550 (Japan); Obata, Hajime [Atmosphere and Ocean Research Institute, The Tokyo University, 5-1-5 Kashiwanoha, Kashiwa-shi, Chiba 277-8564 (Japan); Nagai, Hisao [College of Humanities and Sciences, Nihon University, 3-25-40, Sakurajosui, Setagaya-ku, Tokyo 156-8550 (Japan)

    2014-12-10

    Highlights: • We developesd the simplest and robust SPE method for ultra low picomolar level beryllium in seawater. • Just silica gel column can quantitatively adsorb beryllium in neutral pH condition containing natural seawater. • EDTA solution can eliminate seawater matrixes retaining Be in the column, which optimize to ICP-MS detemination. • Accurate and precise Be data have been obtained for natural seawater from North Pacific Ocean. - Abstract: A robust and rapid method for the determination of natural levels of beryllium (Be) in seawater was developed to facilitate mapping Be concentrations in the ocean. A solid-phase extraction method using a silica gel column was applied for preconcentration and purification of Be in seawater prior to determination of Be concentrations with inductively coupled plasma mass spectrometry (ICP-MS). Be was quantitatively adsorbed onto silica gel from solutions with pH values ranging from 6.3 to 9, including natural seawater. The chelating agent ethylenediamine tetraacetic acid was used to remove other ions in the seawater matrix (Na, Mg, and Ca) that interfere with the ICP-MS analysis. The reproducibility of the method was 3% based on triplicate analyses of natural seawater samples, and the detection limit was 0.4 pmol kg{sup −1} for 250 mL of seawater, which is sufficient for the analysis of seawater in the open ocean. The method was then used to determine the vertical profile of Be in the eastern North Pacific Ocean, which was found to be a recycled-type profile in which the Be concentration increased with depth from the surface (7.2 pmol kg{sup −1} at <200 m) to deep water (29.2 pmol kg{sup −1} from 3500 m to the bottom)

  14. Determination of picomolar beryllium levels in seawater with inductively coupled plasma mass spectrometry following silica-gel preconcentration

    International Nuclear Information System (INIS)

    Tazoe, Hirofumi; Yamagata, Takeyasu; Obata, Hajime; Nagai, Hisao

    2014-01-01

    Highlights: • We developesd the simplest and robust SPE method for ultra low picomolar level beryllium in seawater. • Just silica gel column can quantitatively adsorb beryllium in neutral pH condition containing natural seawater. • EDTA solution can eliminate seawater matrixes retaining Be in the column, which optimize to ICP-MS detemination. • Accurate and precise Be data have been obtained for natural seawater from North Pacific Ocean. - Abstract: A robust and rapid method for the determination of natural levels of beryllium (Be) in seawater was developed to facilitate mapping Be concentrations in the ocean. A solid-phase extraction method using a silica gel column was applied for preconcentration and purification of Be in seawater prior to determination of Be concentrations with inductively coupled plasma mass spectrometry (ICP-MS). Be was quantitatively adsorbed onto silica gel from solutions with pH values ranging from 6.3 to 9, including natural seawater. The chelating agent ethylenediamine tetraacetic acid was used to remove other ions in the seawater matrix (Na, Mg, and Ca) that interfere with the ICP-MS analysis. The reproducibility of the method was 3% based on triplicate analyses of natural seawater samples, and the detection limit was 0.4 pmol kg −1 for 250 mL of seawater, which is sufficient for the analysis of seawater in the open ocean. The method was then used to determine the vertical profile of Be in the eastern North Pacific Ocean, which was found to be a recycled-type profile in which the Be concentration increased with depth from the surface (7.2 pmol kg −1 at <200 m) to deep water (29.2 pmol kg −1 from 3500 m to the bottom)

  15. Enhancement of Extraction of Uranium from Seawater

    International Nuclear Information System (INIS)

    Al-Sheikhly, Mohamad; Dietz, Travis; Tsinas, Zois; Tomaszewski, Claire; Pazos, Ileana M.; Nigliazzo, Olga; Li, Weixing; Adel-Hadadi, Mohamad; Barkatt, Aaron

    2016-01-01

    Even at a concentration of 3 @@g/L, the world@@@s oceans contain a thousand times more uranium than currently know terrestrial sources. In order to take advantage of this stockpile, methods and materials must be developed to extract it efficiently, a difficult task considering the very low concentration of the element and the competition for extraction by other atoms in seawater such as sodium, calcium, and vanadium. The majority of current research on methods to extract uranium from seawater are vertical explorations of the grafting of amidoxime ligand, which was originally discovered and promoted by Japanese studies in the late 1980s. Our study expands on this research horizontally by exploring the effectiveness of novel uranium extraction ligands grafted to the surface of polymer substrates using radiation. Through this expansion, a greater understanding of uranium binding chemistry and radiation grafting effects on polymers has been obtained. While amidoxime-functionalized fabrics have been shown to have the greatest extraction efficiency so far, they suffer from an extensive chemical processing step which involves treatment with powerful basic solutions. Not only does this add to the chemical waste produced in the extraction process and add to the method@@@s complexity, but it also significantly impacts the regenerability of the amidoxime fabric. The approach of this project has been to utilize alternative, commercially available monomers capable of extracting uranium and containing a carbon-carbon double bond to allow it to be grafted using radiation, specifically phosphate, oxalate, and azo monomers. The use of commercially available monomers and radiation grafting with electron beam or gamma irradiation will allow for an easily scalable fabrication process once the technology has been optimized. The need to develop a cheap and reliable method for extracting uranium from seawater is extremely valuable to energy independence and will extend the quantity of

  16. CdS nanobubbles and Cd-DMS nanosheets: solvothermal synthesis and formation mechanism.

    Science.gov (United States)

    Feng, Miao; Zhan, Hongbing

    2013-02-01

    CdS nanobubbles and Cd-DMS nanosheets have been prepared by a solvothermal method from a solution of Cd2+ in dimethyl sulfoxide in the absence of elemental S. A formation mechanism for the nanobubble morphology arising during the CdS nanocrystal growth has been proposed, based on the results of transmission electron microscopy and photoluminescence spectrophotometry. The correlation of the morphology with reaction time was also suggested, and may be applicable to the solvothermal synthesis of other nanomaterials.

  17. Surface functionalization of Cu-Ni alloys via grafting of a bactericidal polymer for inhibiting biocorrosion by Desulfovibrio desulfuricans in anaerobic seawater.

    Science.gov (United States)

    Yuan, S J; Liu, C K; Pehkonen, S O; Bai, R B; Neoh, K G; Ting, Y P; Kang, E T

    2009-01-01

    A novel surface modification technique was developed to provide a copper nickel alloy (M) surface with bactericidal and anticorrosion properties for inhibiting biocorrosion. 4-(chloromethyl)-phenyl tricholorosilane (CTS) was first coupled to the hydroxylated alloy surface to form a compact silane layer, as well as to confer the surface with chloromethyl functional groups. The latter allowed the coupling of 4-vinylpyridine (4VP) to generate the M-CTS-4VP surface with biocidal functionality. Subsequent surface graft polymerization of 4VP, in the presence of benzoyl peroxide (BPO) initiator, from the M-CTS-4VP surface produced the poly(4-vinylpyridine) (P(4VP)) grafted surface, or the M-CTS-P(4VP) surface. The pyridine nitrogen moieties on the M-CTS-P(4VP) surface were quaternized with hexylbromide to produce a high concentration of quaternary ammonium groups. Each surface functionalization step was ascertained by X-ray photoelectron spectroscopy (XPS) and static water contact angle measurements. The alloy with surface-quaternized pyridinium cation groups (N+) exhibited good bactericidal efficiency in a Desulfovibrio desulfuricans-inoculated seawater-based modified Barr's medium, as indicated by viable cell counts and fluorescence microscopy (FM) images of the surface. The anticorrosion capability of the organic layers was verified by the polarization curve and electrochemical impedance spectroscopy (EIS) measurements. In comparison, the pristine (surface hydroxylated) Cu-Ni alloy was found to be readily susceptible to biocorrosion under the same environment.

  18. Mercury isotope signatures of seawater discharged from a coal-fired power plant equipped with a seawater flue gas desulfurization system.

    Science.gov (United States)

    Lin, Haiying; Peng, Jingji; Yuan, Dongxing; Lu, Bingyan; Lin, Kunning; Huang, Shuyuan

    2016-07-01

    Seawater flue gas desulfurization (SFGD) systems are commonly used to remove acidic SO2 from the flue gas with alkaline seawater in many coastal coal-fired power plants in China. However, large amount of mercury (Hg) originated from coal is also transferred into seawater during the desulfurization (De-SO2) process. This research investigated Hg isotopes in seawater discharged from a coastal plant equipped with a SFGD system for the first time. Suspended particles of inorganic minerals, carbon residuals and sulfides are enriched in heavy Hg isotopes during the De-SO2 process. δ(202)Hg of particulate mercury (PHg) gradually decreased from -0.30‰ to -1.53‰ in study sea area as the distance from the point of discharge increased. The results revealed that physical mixing of contaminated De-SO2 seawater and uncontaminated fresh seawater caused a change in isotopic composition of PHg isotopes in the discharging area; and suggested that both De-SO2 seawater and local background contributed to PHg. The impacted sea area predicted with isotopic tracing technique was much larger than that resulted from a simple comparison of pollutant concentration. It was the first attempt to apply mercury isotopic composition signatures with two-component mixing model to trace the mercury pollution and its influence in seawater. The results could be beneficial to the coal-fired plants with SFGD systems to assess and control Hg pollution in sea area. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Overview of the nuclear fuel resources – seawater uranium recovery program sponsored by the U.S. Department of Energy

    International Nuclear Information System (INIS)

    Kung, S.

    2014-01-01

    For nuclear energy to remain a sustainable energy source, there must be assurance that an economically viable supply of nuclear fuel is available. One major goal of the Fuel Cycle Technology Research and Development (R&D) Program in the United States Department of Energy (DOE), Office of Nuclear Energy (NE) is to develop sustainable fuel cycles options. The development of technology to recover uranium from seawater has the potential to fulfill this program goal. Seawater uranium recovery technology is identified in the U.S. DOE NE Roadmap as an area most appropriate for federal involvement to support long-term, “game-changing” approach. Seawater contains more than 4 billion metric tons of dissolved uranium. This unconventional uranium resource, combined with a suitable extraction cost, can potentially meet the uranium demands for centuries to come. The challenge, however, is the low concentration of uranium in seawater – approximately 3.3 ppb. A multidisciplinary team from the U.S. national laboratories, universities, and research institutes has been assembled to address this challenge. Polymeric adsorbents materials containing amidoxime ligands, developed at the Oak Ridge National Laboratory (ORNL), have demonstrated great promise for the extraction of uranium from seawater. These ORNL adsorbents showed adsorption capacities for the extraction of uranium from seawater that exceed 3 mg U/g adsorbent in testing at the Pacific Northwest National Laboratory Marine Sciences Laboratory. A key component of this novel technology lies in the unique high surface-area polyethylene fibers that considerably increase the surface area and thus the grafting yield of functional groups without compromising its mechanical properties. In addition, high surface area nanomaterial adsorbents are under development at ORNL with the goal of increasing uranium adsorption capacity by taking advantage of the high surface areas and tunable porosity of carbon-based nanomaterials

  20. Rapid determination of 90Sr in seawater

    International Nuclear Information System (INIS)

    Pavlotskaya, F.I.; Moskin, A.I.

    1994-01-01

    A method for determining 90 Sr in seawater that is based on direct isolation and radiochemical purification of daughter 90 Y is proposed. The analysis time is 6-8 h. The chemical yield of the Y-carrier during the 90 Sr determination from 35 liters of seawater varies in the range 37-69%. The analysis uncertainty is 90 Sr from seawater and subsequent isolation of 90 Y

  1. Selective quantitation of the neurotoxin BMAA by use of hydrophilic-interaction liquid chromatography-differential mobility spectrometry-tandem mass spectrometry (HILIC-DMS-MS/MS).

    Science.gov (United States)

    Beach, Daniel G; Kerrin, Elliott S; Quilliam, Michael A

    2015-11-01

    The neurotoxin β-N-methylamino-L-alanine (BMAA) has been reported in cyanobacteria and shellfish, raising concerns about widespread human exposure. However, inconsistent results for BMAA analysis have led to controversy. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) is the most appropriate method for analysis of BMAA, but the risk of interference from isomers, other sample components, and the electrospray background is still present. We have investigated differential mobility spectrometry (DMS) as an ion filter to improve selectivity in the hydrophilic interaction liquid chromatographic (HILIC)-MS/MS determination of BMAA. We obtained standards for two BMAA isomers not previously analyzed by HILIC-MS, β-amino-N-methylalanine and 3,4-diaminobutanoic acid, and the typically used 2,4-diaminobutanoic acid and N-(2-aminoethyl)glycine. DMS separation of BMAA from these isomers was achieved and optimized conditions were used to develop a sensitive and highly selective multidimensional HILIC-DMS-MS/MS method. This work revealed current technical limitations of DMS for trace quantitation, and practical solutions were implemented. Accurate control of low levels of DMS carrier gas modifier was essential, but required external metering. The linearity of our optimized method was excellent from 0.01 to 6 μmol L(-1). The instrumental LOD was 0.4 pg BMAA injected on-column and the estimated method LOD was 20 ng g(-1) dry weight for BMAA in sample matrix. The method was used to analyze cycad plant tissue, a cyanobacterial reference material, and mussel tissues, by use of isotope-dilution quantitation with deuterated BMAA. This confirmed the presence of BMAA and several of its isomers in cycad and mussel tissues, including commercially available mussel tissue reference materials certified for other biotoxins. Graphical Abstract Differential Mobility Spectrometry is used to increases the selectivity of BMAA analysis by HILIC-MS/MS.

  2. Seawater desalination with nuclear power

    International Nuclear Information System (INIS)

    2005-01-01

    Nuclear power helps reduce costs for energy-intensive processes such as seawater desalination. A new generation of innovative small and medium nuclear power plants could co-generate electricity and potable water from seawater, both safely and at competitive prices in today's market. The IAEA provides technical support to Member States facing water shortage problems, on assessing the viability of nuclear power in seawater desalination. The support, usually channelled through national Technical Cooperation (TC) projects, can take several forms, ranging from educational training and technical advice on feasibility studies to design and safety review of demonstration projects. The IAEA offers a software tool (DEEP) that can be used to evaluate the economics of the different desalination and heat source configurations, including nuclear and fossil options

  3. Conceptual design on uranium recovery plant from seawater

    International Nuclear Information System (INIS)

    Kato, Toshiaki; Okugawa, Katsumi; Sugihara, Yutaka; Matsumura, Tsuyoshi

    1999-01-01

    Uranium containing in seawater is extremely low concentration, which is about 3 mg (3 ppb) per 1 ton of seawater. Recently, a report on development of a more effective collector of uranium in seawater (a radiation graft polymerization product of amidoxime onto polyethylene fiber) was issued by Japan Atomic Energy Research Institute. In this paper, an outline design of a uranium recovery plant from seawater was conducted on a base of the collector. As a result of cost estimation, the collection cost of seawater uranium using this method was much higher than that of uranium mine on land and described in the Red Book for mineral uranium cost. In order to make the seawater uranium cost comparable to the on-land uranium cost, it is necessary to establish comprehensive efforts in future technical development, such as development in absorption property of uranium with the collector, resolution method using less HCl, and so forth. (G.K.)

  4. Hydrochemical and isotopic characteristics of estuarial seawater and river water of Bailanghe in Laizhou Bay, China

    Science.gov (United States)

    Yang, Qiaofeng; Xu, Suning; Wang, Ruijiu; Li, Wenpeng; Wang, Zhiyi; Mei, Junjun; Ding, Zhilei; Yang, Peijie; Yu, Liangju; Lv, Tieying; Bai, Gang; Kang, Wei

    2016-04-01

    In the study of seawater intrusion, seawater is usually taken as an end-member that mixes with other source(s). However, compared to standard seawater, the coastal seawater particularly that near the estuary, can be strongly influenced by the rivers into the sea and by coastal human activities. Their composition can be thus continuously changed and redistributed with space and time. Therefore, before investigating seawater intrusion in a certain area, it is essentially important to determine the features of the estuarine seawater (e.g. the mixture percentage between standard seawater and river water). In this study, we aimed to gain a clear situation of the seawater intrusion in Laizhou Bay, Southern Bohai, China. The issue aforementioned was investigated by comparing the stable isotopic and hydrochemical composition of the marine and river water collected in this area. Samples investigated include 5 surface water samples collected at the downstream of the Bailanghe and 7 seawater samples near the estuary of Laizhou Bay. Inert tracers (δD, δ18O, Cl, Br) and reaction tracers (Na, Mg, SO4, HCO3, Ca, NO3) are particularly analyzed. The major results are as follows: 1) All the river water samples fall below the Global Meteoric Water Line in the δD - δ18O diagram, reflecting evaporation of the upstream reservoir water. The seawater samples fall on the mixing line of standard seawater and the river water in the stable isotopic diagram. 2) The Cl-δ18O diagram indicates widespread dissolution of evaporate into the river, while high concentration of Ca and HCO3-, as well as the SO42- - Cl relation of the river water samples reflect the dissolution of CO2 , carbonate and sulfate in the atmosphere and on the ground. 3) The Br/Cl ratios of seawater samples are closed to the marine ratios. This together with the plots of major ions vs. Cl suggest that the seawater samples are originated from the mixture of standard seawater and river water. Therefore, when referring to the

  5. Elution of Uranium and Transition Metals from Amidoxime-Based Polymer Adsorbents for Sequestering Uranium from Seawater

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Horng-Bin; Kuo, Li-Jung; Wai, Chien M.; Miyamoto, Naomi; Joshi, Ruma; Wood, Jordana R.; Strivens, Jonathan E.; Janke, Christopher J.; Oyola, Yatsandra; Das, Sadananda; Mayes, Richard T.; Gill, Gary A.

    2015-11-30

    High-surface-area amidoxime and carboxylic acid grafted polymer adsorbents developed at Oak Ridge National Laboratory were tested for sequestering uranium in a flowing seawater flume system at the PNNL-Marine Sciences Laboratory. FTIR spectra indicate that a KOH conditioning process is necessary to remove the proton from the carboxylic acid and make the sorbent effective for sequestering uranium from seawater. The alkaline conditioning process also converts the amidoxime groups to carboxylate groups in the adsorbent. Both Na2CO3-H2O2 and hydrochloric acid elution methods can remove ~95% of the uranium sequestered by the adsorbent after 42 days of exposure in real seawater. The Na2CO3-H2O2 elution method is more selective for uranium than conventional acid elution. Iron and vanadium are the two major transition metals competing with uranium for adsorption to the amidoxime-based adsorbents in real seawater.

  6. Potential Effects of Desalinated Seawater on Arteriosclerosis in Rats.

    Science.gov (United States)

    Duan, Lian; Zhang, Li Xia; Zhang, Shao Ping; Kong, Jian; Zhi, Hong; Zhang, Ming; Lu, Kai; Zhang, Hong Wei

    2017-10-01

    To evaluate the potential risk of arteriosclerosis caused by desalinated seawater, Wistar rats were provided desalinated seawater over a 1-year period, and blood samples were collected at 0, 90, 180, and 360 days. Blood calcium, magnesium, and arteriosclerosis-related indicators were investigated. Female rats treated with desalinated seawater for 180 days showed lower magnesium levels than the control rats (P seawater for 360 days (P seawater, and no increase in risk of arteriosclerosis was observed. Copyright © 2017 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.

  7. Uranium from seawater

    International Nuclear Information System (INIS)

    1974-12-01

    The report concerns the possibilities of extracting uranium from seawater using either 'tidal' and 'pumped' schemes. It was decided to undertake an initial exercise on the pumped scheme. It was to take into account not only the direct energy requirements, but also the indirect energy inputs needed to produce the capital equipment, operating materials, etc. The report begins with a discussion of the technique of energy accounting, and the merits and limitations of the two principal approaches are compared. These are: 'Process Analysis' (or 'Energy Cost of Materials') and 'Input-Output Analysis' (or 'Energy Cost of Money'). A comparison is made between the energy cost of the tidal and pumped schemes, by both methods of analysis. A 'Best Estimate' is compiled calling on both methods, and this indicates that on an energy cost basis the pumped scheme is three times as expensive as the tidal scheme. Intermediate schemes are feasible, however. There is some evidence that the energy cost of an ore refining process with an initial concentration of 0.007% would be of the same order as that of the pumped seawater scheme. The energy cost of generating electricity using seawater uranium in an SGHWR is compared with the present UK generating system as a whole. (U.K.)

  8. Gaseous (DMS, MSA, SO2, H2SO4 and DMSO and particulate (sulfate and methanesulfonate sulfur species over the northeastern coast of Crete

    Directory of Open Access Journals (Sweden)

    H. Bardouki

    2003-01-01

    Full Text Available A detailed study of the levels, the temporal and diurnal variability of the main compounds involved in the biogenic sulfur cycle was carried out in Crete (Eastern Mediterranean during the Mediterranean Intensive Oxidant Study (MINOS field experiment in July-August 2001. Intensive measurements of gaseous dimethylsulfide (DMS, dimethylsulfoxide (DMSO, sulfur dioxide (SO2, sulfuric (H2SO4 and methanesulfonic acids (MSA and particulate sulfate (SO42- and methanesulfonate (MS- have been performed during the campaign. Dimethylsulfide (DMS levels ranged from 2.9 to 136 pmol·mol-1 (mean value of 21.7 pmol·mol-1 and showed a clear diurnal variation with daytime maximum. During nighttime DMS levels fall close or below the detection limit of 2 pmol·mol-1. Concurrent measurements of OH and NO3 radicals during the campaign indicate that NO3 levels can explain most of the observed diurnal variation of DMS. Dimethylsulfoxide (DMSO ranged between 0.02 and 10.1 pmol·mol-1 (mean value of 1.7 pmol·mol-1 and presents a diurnal variation similar to that of DMS. SO2 levels ranged from 220 to 2970 pmol·mol-1 (mean value of 1030 pmol·mol-1, while nss-SO42- and MS- ranged from 330 to 7100 pmol·mol-1, (mean value of 1440 pmol·mol-1 and 1.1 to 37.5 pmol·mol-1 (mean value of 11.5 pmol·mol-1 respectively. Of particular interest are the measurements of gaseous MSA and H2SO4. MSA ranged from below the detection limit (3x104 to 3.7x107 molecules cm-3, whereas H2SO4 ranged between 1x105 and 9.0x107 molecules cm-3. The measured H2SO4 maxima are among the highest reported in literature and can be attributed to high insolation, absence of precipitation and increased SO2 levels in the area. From the concurrent SO2, OH, and H2SO4 measurements a sticking coefficient of 0.52±0.28 was calculated for H2SO4. From the concurrent MSA, OH, and DMS measurements the yield of gaseous MSA from the OH-initiated oxidation of DMS was calculated to range between 0.1-0.4%. This low MSA

  9. Preparation of Pt deposited nanotubular TiO2 as cathodes for enhanced photoelectrochemical hydrogen production using seawater electrolytes

    International Nuclear Information System (INIS)

    Nam, Wonsik; Oh, Seichang; Joo, Hyunku; Yoon, Jaekyung

    2011-01-01

    The purpose of this study was to develop effective cathodes to increase the production of hydrogen and use the seawater, an abundant resource in the earth as the electrolyte in photoelectrochemical systems. In order to fabricate the Pt/TiO 2 cathodes, various contents of the Pt precursor (0-0.4 wt%) deposited by the electrodeposition method were used. On the basis of the hydrogen evolution rate, 0.2 wt% Pt/TiO 2 was observed to exhibit the best performance among the various Pt/TiO 2 cathodes with the natural seawater and two concentrated seawater electrolytes obtained from single (nanofiltration) and combined membrane (nanofiltration and reverse osmosis) processes. The surface characterizations exhibited that crystal structures and morphological properties of Pt and TiO 2 found the results of XRD pattern and SEM/TEM images, respectively. - Graphical abstract: On the basis of photoelectrochemical hydrogen production, 0.2 wt% Pt/TiO 2 was observed to exhibit the best performance among the various Pt/TIO 2 cathodes with natural seawater. In comparison of hydrogen evolution rate with various seawater electrolytes, 0.2 wt% Pt/TiO 2 was found to show the better performance as cathode with the concentrated seawater electrolytes obtained from membrane. Highlights: → Pt deposited TiO 2 electrodes are used as cathode in PEC H 2 production. → Natural and concentrated seawater by membranes are used as electrolytes in PEC. → Pt/TiO 2 shows a good performance as cathode with seawater electrolytes. → H 2 evolution rate increases with more concentrated seawater electrolyte. → Highly saline seawater is useful resource for H 2 production.

  10. Seawater movement in the Japan Sea inferred from 14C measurement in seawater

    International Nuclear Information System (INIS)

    Otosaka, Shigeyoshi; Tanaka, Takayuki; Togawa, Orihiko; Amano, Hikaru; Aramaki, Takafumi

    2008-01-01

    Research Group for Environmental Science, JAEA has carried out oceanographic observations in the Japan Sea since 1997 to clarify the biogeochemical cycle in the Japan Sea. More than 3,000 seawater samples for measurement of radiocarbon were collected during the observations, and radiocarbon in the seawater samples was measured at AMS facility in JAEA Mutsu. In this paper, formation and circulation of water mass in the northern Japan Sea were discussed using analysis of radiocarbon and hydrographic data (e.g. salinity, temperature, nutrients). (author)

  11. Estimates of ikaite export from sea ice to the underlying seawater in a sea ice–seawater mesocosm

    Directory of Open Access Journals (Sweden)

    N.-X. Geilfus

    2016-09-01

    Full Text Available The precipitation of ikaite and its fate within sea ice is still poorly understood. We quantify temporal inorganic carbon dynamics in sea ice from initial formation to its melt in a sea ice–seawater mesocosm pool from 11 to 29 January 2013. Based on measurements of total alkalinity (TA and total dissolved inorganic carbon (TCO2, the main processes affecting inorganic carbon dynamics within sea ice were ikaite precipitation and CO2 exchange with the atmosphere. In the underlying seawater, the dissolution of ikaite was the main process affecting inorganic carbon dynamics. Sea ice acted as an active layer, releasing CO2 to the atmosphere during the growth phase, taking up CO2 as it melted and exporting both ikaite and TCO2 into the underlying seawater during the whole experiment. Ikaite precipitation of up to 167 µmolkg−1 within sea ice was estimated, while its export and dissolution into the underlying seawater was responsible for a TA increase of 64–66 µmolkg−1 in the water column. The export of TCO2 from sea ice to the water column increased the underlying seawater TCO2 by 43.5 µmolkg−1, suggesting that almost all of the TCO2 that left the sea ice was exported to the underlying seawater. The export of ikaite from the ice to the underlying seawater was associated with brine rejection during sea ice growth, increased vertical connectivity in sea ice due to the upward percolation of seawater and meltwater flushing during sea ice melt. Based on the change in TA in the water column around the onset of sea ice melt, more than half of the total ikaite precipitated in the ice during sea ice growth was still contained in the ice when the sea ice began to melt. Ikaite crystal dissolution in the water column kept the seawater pCO2 undersaturated with respect to the atmosphere in spite of increased salinity, TA and TCO2 associated with sea ice growth. Results indicate that ikaite export from sea ice and its dissolution in the underlying

  12. Non‐diluted seawater enhances nasal ciliary beat frequency and wound repair speed compared to diluted seawater and normal saline

    Science.gov (United States)

    Bonnomet, Arnaud; Luczka, Emilie; Coraux, Christelle

    2016-01-01

    Background The regulation of mucociliary clearance is a key part of the defense mechanisms developed by the airway epithelium. If a high aggregate quality of evidence shows the clinical effectiveness of nasal irrigation, there is a lack of studies showing the intrinsic role of the different irrigation solutions allowing such results. This study investigated the impact of solutions with different pH and ionic compositions, eg, normal saline, non‐diluted seawater and diluted seawater, on nasal mucosa functional parameters. Methods For this randomized, controlled, blinded, in vitro study, we used airway epithelial cells obtained from 13 nasal polyps explants to measure ciliary beat frequency (CBF) and epithelial wound repair speed (WRS) in response to 3 isotonic nasal irrigation solutions: (1) normal saline 0.9%; (2) non‐diluted seawater (Physiomer®); and (3) 30% diluted seawater (Stérimar). The results were compared to control (cell culture medium). Results Non‐diluted seawater enhanced the CBF and the WRS when compared to diluted seawater and to normal saline. When compared to the control, it significantly enhanced CBF and slightly, though nonsignificantly, improved the WRS. Interestingly, normal saline markedly reduced the number of epithelial cells and ciliated cells when compared to the control condition. Conclusion Our results suggest that the physicochemical features of the nasal wash solution is important because it determines the optimal conditions to enhance CBF and epithelial WRS thus preserving the respiratory mucosa in pathological conditions. Non‐diluted seawater obtains the best results on CBF and WRS vs normal saline showing a deleterious effect on epithelial cell function. PMID:27101776

  13. Coral calcifying fluid pH is modulated by seawater carbonate chemistry not solely seawater pH.

    Science.gov (United States)

    Comeau, S; Tambutté, E; Carpenter, R C; Edmunds, P J; Evensen, N R; Allemand, D; Ferrier-Pagès, C; Tambutté, S; Venn, A A

    2017-01-25

    Reef coral calcification depends on regulation of pH in the internal calcifying fluid (CF) in which the coral skeleton forms. However, little is known about calcifying fluid pH (pH CF ) regulation, despite its importance in determining the response of corals to ocean acidification. Here, we investigate pH CF in the coral Stylophora pistillata in seawater maintained at constant pH with manipulated carbonate chemistry to alter dissolved inorganic carbon (DIC) concentration, and therefore total alkalinity (A T ). We also investigate the intracellular pH of calcifying cells, photosynthesis, respiration and calcification rates under the same conditions. Our results show that despite constant pH in the surrounding seawater, pH CF is sensitive to shifts in carbonate chemistry associated with changes in [DIC] and [A T ], revealing that seawater pH is not the sole driver of pH CF Notably, when we synthesize our results with published data, we identify linear relationships of pH CF with the seawater [DIC]/[H + ] ratio, [A T ]/ [H + ] ratio and [[Formula: see text

  14. Evaluation of durability of SSCs injected with seawater

    International Nuclear Information System (INIS)

    2012-01-01

    At the units 1 to 4 in the Fukushima Daiichi Nuclear Power Plant, seawater was injected into reactor pressure vessels and spent fuel pools in order to cool down nuclear fuel is after the disaster of the 2011 off the Pacific Coast of Tohoku Earthquake and Tsunami. Therefore, for fuel cladding tubes exposed to seawater and piping items to pour seawater into a nuclear reactor, it was necessary to evaluate structural integrity under the seawater environment. And then, JNES carried out the safety research of 'Evaluation of Durability of SSCs injected with Seawater' in FY2011. The contents and the results obtained from the search are as follows; (1) For the pipes and nuclear reactor containment vessels, corrosion tests under high temperature seawater at 50degC and 80degC were carried out for the carbon steel that corrosion resistance was less. The data of relationship between a dipping time upto 1,500h and a corrosion rate were obtained as parameters at chloride ion (CI - ) content and the temperature of the seawater. As the results, the corrosion rate was almost 0.1 mm/y for the carbon steel SGV480. No significant influence of CT - content and the temperature of the seawater was confirmed. (2) Corrosion tests were carried out to obtain the relations of time and corrosion under different CI - content conditions for the simulated fuel rod specimens in seawater at 90degC for durations upto 1,200h. As the results, very little corrosion was observed on Zry-2 cladding tube. Brown rust was slightly appeared on the nut made of stainless steel and the lower tie plate made of cast stainless steel. Thinning and corrosion pit were not observed. (author)

  15. Improvement of seawater booster pump outlet check valve

    International Nuclear Information System (INIS)

    Li Xuning; Du Yansong; Huang Huimin

    2010-01-01

    Conventional island seawater booster pump set of QNPC 310 MWe unit are very important in the whole circulating cooling system, and the integrate function of seawater booster pump outlet check valve is the foundation of steady operation of the seawater booster pump set. The article mainly introduce that through the analyses to the reason to the problem that the seawater booster pump outlet check valve of QNPC 310 MWe unit appeared in past years by our team, and considering the influence of operation condition and circumstance, the team improve the seawater booster pump outlet check valve from swing check valve to shuttle check valve which operate more appropriately in the system. By the test of continuous practice, we make further modification to the inner structure of shuttle check valve contrapuntally, and therefore we solve the problem in seawater booster pump outlet check valve fundamentally which has troubled the security of system operation in past years, so we realize the aim of technical improvement and ensure that the system operate in safety and stability. (authors)

  16. Assessment of Selected Heavy Metals in Seawater and Sediment at Klang Coastal Area Malaysia

    International Nuclear Information System (INIS)

    Noor Aziatul Aini Hamzan; Farah Fardiana Mohamad Zaini; Mohd Ismail Ibrahim; Nik Azlin Nik Ariffin

    2015-01-01

    Sediments are capable of transporting loads of adsorbed nutrients, pesticides, heavy metals, and other toxins. In this study, the samples of sediment were collected from four sampling points (Kapar, Sungai Puloh, Sementa and North Port) using sediment core sampler. The cores then was sub-sampled by slicing into 1 cm slices and dried at 60 degree Celsius until mass become constant and the weight recorded. The samples were pulverized and sieved through 220 μm stainless steel sieves. Each sub-sample digested using aqua regia acids. For seawater, the samples were evaporated using the hotplate at 60 degree Celsius. The concentration of heavy metals was determined by inductively coupled plasma optical emission spectrometry (ICP-OES). The highest concentration of copper, zinc, iron and lead was observed from seawater samples obtained from Sementa while highest concentration of cadmium was found from Kapar samples). Most of the bottom seawater gives high concentration of the heavy metal compare to the surface. For sediment, the overall concentration of heavy metal in each layer was fluctuated. From the analysis, there is a significant correlation for overall selected heavy metals and the samples (seawater and sediment) that study in this area. (author)

  17. Biodegradation of Halloysite Nanotubes-Polyester Nanocomposites Exposed to Short Term Seawater Immersion

    Directory of Open Access Journals (Sweden)

    Mohd Shahneel Saharudin

    2017-07-01

    Full Text Available Halloysite nanotubes (HNTs-polyester nanocomposites with four different concentrations were produced using solution casting technique and the biodegradation effect of short-term seawater exposure (120 h was studied. Monolithic polyester was observed to have the highest seawater absorption with 1.37%. At 0.3 wt % HNTs reinforcement, the seawater absorption dropped significantly to the lowest value of 0.77% due to increase of liquid diffusion path. For samples tested in dry conditions, the Tg, storage modulus, tensile properties and flexural properties were improved. The highest improvement of Tg was from 79.3 to 82.4 °C (increase 3.1 °C in the case of 0.3 wt % HNTs. This can be associated with the exfoliated HNTs particles, which restrict the mobility of polymer chains and thus raised the Tg. After seawater exposure, the Tg, storage modulus, tensile properties and flexural properties of polyester and its nanocomposites were decreased. The Young’s modulus of 0.3 wt % HNTs-polyester dropped 20% while monolithic polyester dropped up to 24% compared to their values in dry condition. Apart from that, 29% flexural modulus reduction was observed, which was 18% higher than monolithic polyester. In contrast, fracture toughness and surface roughness increased due to plasticization effect. The presence of various microbial communities caused gradual biodegradation on the microstructure of the polyester matrix as also evidently shown by SEM images.

  18. Accurate Measurements of the Dielectric Constant of Seawater at L Band

    Science.gov (United States)

    Lang, Roger; Zhou, Yiwen; Utku, Cuneyt; Le Vine, David

    2016-01-01

    This paper describes measurements of the dielectric constant of seawater at a frequency of 1.413 GHz, the center of the protected band (i.e., passive use only) used in the measurement of sea surface salinity from space. The objective of the measurements is to accurately determine the complex dielectric constant of seawater as a function of salinity and temperature. A resonant cylindrical microwave cavity in transmission mode has been employed to make the measurements. The measurements are made using standard seawater at salinities of 30, 33, 35, and 38 practical salinity units over a range of temperatures from 0 degree C to 35 degree C in 5 degree C intervals. Repeated measurements have been made at each temperature and salinity. Mean values and standard deviations are then computed. The total error budget indicates that the real and imaginary parts of the dielectric constant have a combined standard uncertainty of about 0.3 over the range of salinities and temperatures considered. The measurements are compared with the dielectric constants obtained from the model functions of Klein and Swift and those of Meissner and Wentz. The biggest differences occur at low and high temperatures.

  19. Bacterial cell numbers and community structures of seawater biofilms depend on the attachment substratum

    KAUST Repository

    Yap, Scott A.

    2018-02-02

    Seawater is increasingly being used as a source for various industrial applications. For such applications, biofilm growth creates various problems including but not limited to pipe biocorrosion. In this study, it is hypothesized that the material type is preferred by certain bacterial populations in the seawater to attach and establish biofilms. By comparing differences in the total cell counts and microbial communities attached to high-density polyethylene (HDPE), polycarbonate, stainless steel (SS316) and titanium, the appropriate material can be used to minimize biofilm growth. All four materials have hydrophilic surfaces, but polycarbonate exhibits higher surface roughness. There were no significant differences in the cell numbers attached to polycarbonate, HDPE and titanium. Instead, there were significantly fewer cells attached to SS316. However, there was a higher relative abundance of genera associated with opportunistic pathogens on SS316. Copy numbers of genes representing Desulfobacteraceae and Desulfobulbaceae, both of which are sulfate-reducing bacteria (SRB), were approximately 10-fold higher in biofilms sampled from SS316. The enrichment of SRB in the biofilm associated with SS316 indicates that this material may be prone to biocorrosion. This study highlights the need for industries to consider the choice of material used in seawater applications to minimize microbial-associated problems.

  20. Bacterial cell numbers and community structures of seawater biofilms depend on the attachment substratum

    KAUST Repository

    Yap, Scott A.; Scarascia, Giantommaso; Hong, Pei-Ying

    2018-01-01

    Seawater is increasingly being used as a source for various industrial applications. For such applications, biofilm growth creates various problems including but not limited to pipe biocorrosion. In this study, it is hypothesized that the material type is preferred by certain bacterial populations in the seawater to attach and establish biofilms. By comparing differences in the total cell counts and microbial communities attached to high-density polyethylene (HDPE), polycarbonate, stainless steel (SS316) and titanium, the appropriate material can be used to minimize biofilm growth. All four materials have hydrophilic surfaces, but polycarbonate exhibits higher surface roughness. There were no significant differences in the cell numbers attached to polycarbonate, HDPE and titanium. Instead, there were significantly fewer cells attached to SS316. However, there was a higher relative abundance of genera associated with opportunistic pathogens on SS316. Copy numbers of genes representing Desulfobacteraceae and Desulfobulbaceae, both of which are sulfate-reducing bacteria (SRB), were approximately 10-fold higher in biofilms sampled from SS316. The enrichment of SRB in the biofilm associated with SS316 indicates that this material may be prone to biocorrosion. This study highlights the need for industries to consider the choice of material used in seawater applications to minimize microbial-associated problems.

  1. Experiences of corrosion and corrosion protection in seawater systems in the Nordic countries

    International Nuclear Information System (INIS)

    Henrikson, S.

    1985-01-01

    A summary is given of the experience of the corrosion resistance of pumps, heat exchangers, valves and pipings in different seawater cooling systems in Scandinavia, including power reactor cooling systems in Finland and Sweden. For pumps and heat exchangers the experience has been so extensive that a clear picture of today's standing can be given. Owing to scanty data concerning valves and pipes, the survey of the corrosion in these components is less well supported. Vertically extended centrifugal pumps are the pumps in general use in power plant cooling systems. To counteract corrosion on pump riser and pump casing having an organic surface coating, and on stainless steel shafts and impellers, these components should be provided with internal and external cathodic protection. For tube and plate type heat exchangers, titanium has proved to be the best material choice. Rubber-enclosed carbon steel pipings, or pipings having a thick coating of epoxy plastic, have shown very strong corrosion resistance in power plant seawater cooling systems. Valves in seawater systems have primarily been affected by corrosion due to poorly executed or damaged organic coating on cast iron. Different seawater-resistant bronzes (red bronze, tin bronze and aluminium bronze) are therefore preferable as valve materials

  2. Wrapping Python around MODFLOW/MT3DMS based groundwater models

    Science.gov (United States)

    Post, V.

    2008-12-01

    Numerical models that simulate groundwater flow and solute transport require a great amount of input data that is often organized into different files. A large proportion of the input data consists of spatially-distributed model parameters. The model output consists of a variety data such as heads, fluxes and concentrations. Typically all files have different formats. Consequently, preparing input and managing output is a complex and error-prone task. Proprietary software tools are available that facilitate the preparation of input files and analysis of model outcomes. The use of such software may be limited if it does not support all the features of the groundwater model or when the costs of such tools are prohibitive. Therefore a Python library was developed that contains routines to generate input files and process output files of MODFLOW/MT3DMS based models. The library is freely available and has an open structure so that the routines can be customized and linked into other scripts and libraries. The current set of functions supports the generation of input files for MODFLOW and MT3DMS, including the capability to read spatially-distributed input parameters (e.g. hydraulic conductivity) from PNG files. Both ASCII and binary output files can be read efficiently allowing for visualization of, for example, solute concentration patterns in contour plots with superimposed flow vectors using matplotlib. Series of contour plots are then easily saved as an animation. The subroutines can also be used within scripts to calculate derived quantities such as the mass of a solute within a particular region of the model domain. Using Python as a wrapper around groundwater models provides an efficient and flexible way of processing input and output data, which is not constrained by limitations of third-party products.

  3. Proteolytic enzymes in seawater: contribution of prokaryotes and protists

    Science.gov (United States)

    Obayashi, Y.; Suzuki, S.

    2016-02-01

    Proteolytic enzyme is one of the major catalysts of microbial processing of organic matter in biogeochemical cycle. Here we summarize some of our studies about proteases in seawater, including 1) distribution of protease activities in coastal and oceanic seawater, 2) responses of microbial community and protease activities in seawater to organic matter amending, and 3) possible contribution of heterotrophic protists besides prokaryotes to proteases in seawater, to clarify cleared facts and remaining questions. Activities of aminopeptidases, trypsin-type and chymotrypsin-type proteases were detected from both coastal and oceanic seawater by using MCA-substrate assay. Significant activities were detected from not only particulate (cell-associated) fraction but also dissolved fraction of seawater, especially for trypsin-type and chymotrypsin-type proteases. Hydrolytic enzymes in seawater have been commonly thought to be mainly derived from heterotrophic prokaryotes; however, it was difficult to determine actual source organisms of dissolved enzymes in natural seawater. Our experiment with addition of dissolved protein to subtropical oligotrophic Pacific water showed drastically enhancement of the protease activities especially aminopeptidases in seawater, and the prokaryotic community structure simultaneously changed to be dominant of Bacteroidetes, indicating that heterotrophic bacteria were actually one of the sources of proteases in seawater. Another microcosm experiment with free-living marine heterotrophic ciliate Paranophrys marina together with an associated bacterium showed that extracellular trypsin-type activity was mainly attributed to the ciliate. The protist seemed to work in organic matter digestion in addition to be a grazer. From the results, we propose a system of organic matter digestion by prokaryotes and protists in aquatic environments, although their actual contribution in natural environments should be estimated in future studies.

  4. Sea-level rise impacts on seawater intrusion in coastal aquifers: Review and integration

    Science.gov (United States)

    Ketabchi, Hamed; Mahmoodzadeh, Davood; Ataie-Ashtiani, Behzad; Simmons, Craig T.

    2016-04-01

    Sea-level rise (SLR) influences groundwater hydraulics and in particular seawater intrusion (SWI) in many coastal aquifers. The quantification of the combined and relative impacts of influential factors on SWI has not previously been considered in coastal aquifers. In the present study, a systematic review of the available literature on this topic is first provided. Then, the potential remaining challenges are scrutinized. Open questions on the effects of more realistic complexities such as gradual SLR, parameter uncertainties, and the associated influences in decision-making models are issues requiring further investigation. We assess and quantify the seawater toe location under the impacts of SLR in combination with recharge rate variations, land-surface inundation (LSI) due to SLR, aquifer bed slope variation, and changing landward boundary conditions (LWBCs). This is the first study to include all of these factors in a single analysis framework. Both analytical and numerical models are used for these sensitivity assessments. It is demonstrated that (1) LSI caused by SLR has a significant incremental impact on the seawater toe location, especially in the flatter coasts and the flux-controlled (FC) LWBCs, however this impact is less than the reported orders of magnitude differences which were estimated using only analytical solutions; (2) LWBCs significantly influence the SLR impacts under almost all conditions considered in this study; (3) The main controlling factors of seawater toe location are the magnitudes of fresh groundwater discharge to sea and recharge rate. Regional freshwater flux entering from the landward boundary and the groundwater hydraulic gradient are the major contributors of fresh groundwater discharge to sea for both FC and head-controlled (HC) systems, respectively; (4) A larger response of the aquifer and larger seawater toe location changes are demonstrable for a larger ratio of the aquifer thickness to the aquifer length particularly in

  5. Non-diluted seawater enhances nasal ciliary beat frequency and wound repair speed compared to diluted seawater and normal saline.

    Science.gov (United States)

    Bonnomet, Arnaud; Luczka, Emilie; Coraux, Christelle; de Gabory, Ludovic

    2016-10-01

    The regulation of mucociliary clearance is a key part of the defense mechanisms developed by the airway epithelium. If a high aggregate quality of evidence shows the clinical effectiveness of nasal irrigation, there is a lack of studies showing the intrinsic role of the different irrigation solutions allowing such results. This study investigated the impact of solutions with different pH and ionic compositions, eg, normal saline, non-diluted seawater and diluted seawater, on nasal mucosa functional parameters. For this randomized, controlled, blinded, in vitro study, we used airway epithelial cells obtained from 13 nasal polyps explants to measure ciliary beat frequency (CBF) and epithelial wound repair speed (WRS) in response to 3 isotonic nasal irrigation solutions: (1) normal saline 0.9%; (2) non-diluted seawater (Physiomer®); and (3) 30% diluted seawater (Stérimar). The results were compared to control (cell culture medium). Non-diluted seawater enhanced the CBF and the WRS when compared to diluted seawater and to normal saline. When compared to the control, it significantly enhanced CBF and slightly, though nonsignificantly, improved the WRS. Interestingly, normal saline markedly reduced the number of epithelial cells and ciliated cells when compared to the control condition. Our results suggest that the physicochemical features of the nasal wash solution is important because it determines the optimal conditions to enhance CBF and epithelial WRS thus preserving the respiratory mucosa in pathological conditions. Non-diluted seawater obtains the best results on CBF and WRS vs normal saline showing a deleterious effect on epithelial cell function. © 2016 The Authors International Forum of Allergy & Rhinology, published by ARSAAOA, LLC.

  6. Seawater sulfate reduction and sulfur isotope fractionation in basaltic systems: interaction of seawater with fayalite and magnetite at 200-3500C

    International Nuclear Information System (INIS)

    Shanks, W.C. III; Bischoff, J.L.; Rosenbauer, R.J.

    1981-01-01

    Sulfate reduction during seawater reaction with fayalite and with magnetite was rapid at 350 0 C, producing equilibrium assemblages of talc-pyrite-hematite-magnetite at low water/rock ratios and talc-pyrite-hematite-anhydrite at higher water/rock ratios. At 250 0 C, seawater reacting with fayalite produced detectable amounts of dissolved H 2 S. At 200 0 C, dissolved H 2 S was not detected, even after 219 days. Reaction stoichiometry indicates that sulfate reduction requires large amounts of H + , which, in subseafloor hydrothermal systems is provided by Mg metasomatism. Seawater contains sufficient Mg to supply all the H + necessary for quantitative reduction of seawater sulfate. Systematics of sulfur isotopes in the 250 and 350 0 C experiments indicate that isotopic equilibrium is reached and can be modeled as a Rayleigh distillation process. Isotopic composition of hydrothermally produced H 2 S in natural systems is strongly dependent upon the seawater/basalt ratio in the geothermal system, which controls the relative sulfide contributions from the two important sulfur sources, seawater sulfate and sulfide phases in basalt. Anhydrite precipitation during geothermal heating severely limits sulfate ingress into high temperature interaction zones. Quantitative sulfate reduction can thus be accomplished without producing strongly oxidized rocks and resultant sulfide sulfur isotope values represent a mixture of seawater and basaltic sulfur. (author)

  7. Enhancement of Extraction of Uranium from Seawater

    Energy Technology Data Exchange (ETDEWEB)

    Al-Sheikhly, Mohamad [Univ. of Maryland, College Park, MD (United States); Dietz, Travis [Univ. of Maryland, College Park, MD (United States); Tsinas, Zois [Univ. of Maryland, College Park, MD (United States); Tomaszewski, Claire [Univ. of Maryland, College Park, MD (United States); Pazos, Ileana M. [Univ. of Maryland, College Park, MD (United States); Nigliazzo, Olga [The Catholic Univ. of America, Washington, DC (United States); Li, Weixing [The Catholic Univ. of America, Washington, DC (United States); Adel-Hadadi, Mohamad [Univ. of Maryland, College Park, MD (United States); Barkatt, Aaron [Univ. of Palermo (Italy)

    2016-04-01

    Even at a concentration of 3 μg/L, the world’s oceans contain a thousand times more uranium than currently know terrestrial sources. In order to take advantage of this stockpile, methods and materials must be developed to extract it efficiently, a difficult task considering the very low concentration of the element and the competition for extraction by other atoms in seawater such as sodium, calcium, and vanadium. The majority of current research on methods to extract uranium from seawater are vertical explorations of the grafting of amidoxime ligand, which was originally discovered and promoted by Japanese studies in the late 1980s. Our study expands on this research horizontally by exploring the effectiveness of novel uranium extraction ligands grafted to the surface of polymer substrates using radiation. Through this expansion, a greater understanding of uranium binding chemistry and radiation grafting effects on polymers has been obtained. While amidoxime-functionalized fabrics have been shown to have the greatest extraction efficiency so far, they suffer from an extensive chemical processing step which involves treatment with powerful basic solutions. Not only does this add to the chemical waste produced in the extraction process and add to the method’s complexity, but it also significantly impacts the regenerability of the amidoxime fabric. The approach of this project has been to utilize alternative, commercially available monomers capable of extracting uranium and containing a carbon-carbon double bond to allow it to be grafted using radiation, specifically phosphate, oxalate, and azo monomers. The use of commercially available monomers and radiation grafting with electron beam or gamma irradiation will allow for an easily scalable fabrication process once the technology has been optimized. The need to develop a cheap and reliable method for extracting uranium from seawater is extremely valuable to energy independence and will extend the quantity of

  8. Seawater bicarbonate removal during hydrothermal circulation

    Science.gov (United States)

    Proskurowski, G. K.; Seewald, J.; Sylva, S. P.; Reeves, E.; Lilley, M. D.

    2013-12-01

    High temperature fluids sampled at hydrothermal vents represent a complex alteration product of water-rock reactions on a multi-component mixture of source fluids. Sources to high-temperature hydrothermal samples include the 'original' seawater present in the recharge limb of circulation, magmatically influenced fluids added at depth as well as any seawater entrained during sampling. High-temperature hydrothermal fluids are typically enriched in magmatic volatiles, with CO2 the dominant species, characterized by concentrations of 10's-100's of mmol/kg (1, 2). Typically, the high concentration of CO2 relative to background seawater bicarbonate concentrations (~2.3 mmol/kg) obscures a full analysis of the fate of seawater bicarbonate during high-temperature hydrothermal circulation. Here we present data from a suite of samples collected over the past 15 years from high-temperature hydrothermal vents at 9N, Endeavour, Lau Basin, and the MAR that have endmember CO2 concentrations less than 10 mmol/kg. Using stable and radiocarbon isotope measurements these samples provide a unique opportunity to examine the balance between 'original' seawater bicarbonate and CO2 added from magmatic sources. Multiple lines of evidence from multiple hydrothermal settings consistently points to the removal of ~80% of the 'original' 2.3 mmol/kg seawater bicarbonate. Assuming that this removal occurs in the low-temperature, 'recharge' limb of hydrothermal circulation, this removal process is widely occurring and has important contributions to the global carbon cycle over geologic time. 1. Lilley MD, Butterfield DA, Lupton JE, & Olson EJ (2003) Magmatic events can produce rapid changes in hydrothermal vent chemistry. Nature 422(6934):878-881. 2. Seewald J, Cruse A, & Saccocia P (2003) Aqueous volatiles in hydrothermal fluids from the Main Endeavour Field, northern Juan de Fuca Ridge: temporal variability following earthquake activity. Earth and Planetary Science Letters 216(4):575-590.

  9. Status of technology of uranium recovery from seawater

    International Nuclear Information System (INIS)

    Sugo, Takanobu; Saito, Kyoichi.

    1990-01-01

    By bringing the solid material called adsorbent in contact with seawater, uranium can be collected, therefore, the adsorbent to which uranium was adsorbed in seawater can be regarded as the resource of uranium storing. To the adsorbent, also rare metals are concentrated in addition to uranium. From such viewpoint, the development of the technology for collecting seawater uranium is important for the Japanese energy policy. The uranium concentration in seawater is about 3 mg/m 3 and its form of dissolution is uranyl tricarbonate ions. The technology of collecting seawater uranium is the separation technology for extracting the component of very low concentration from the aqueous solution containing many components. The total amount of uranium in the whole oceans reaches about 4 billion t, which is about 1000 times as much as the uranium commercially mined on land. It is the target of the technology to make artificial uranium ore of as high quality as possible quickly. The process of collecting seawater uranium comprises adsorption, desorption, separation and enrichment. As the adsorbents, hydrated titanium oxide and chelate resin represented by amidoxime are promising. The adsorption system is described. (K.I.)

  10. Development of an Assessment Procedure for Seawater Intrusion Mitigation

    Science.gov (United States)

    Hsi Ting, F.; Yih Chi, T.

    2017-12-01

    The Pingtung Plain is one of the areas with extremely plentiful groundwater resources in Taiwan. Due to that the application of the water resource is restricted by significant variation of precipitation between wet and dry seasons, groundwater must be used as a recharge source to implement the insufficient surface water resource during dry seasons. In recent years, the coastal aquaculture rises, and the over withdrawn of groundwater by private well results in fast drop of groundwater level. Then it causes imbalance of groundwater supply and leads to serious seawater intrusion in the coastal areas. The purpose of this study is to develop an integrated numerical model of groundwater resources and seawater intrusion. Soil and Water Assessment Tool (SWAT), MODFLOW and MT3D models were applied to analyze the variation of the groundwater levels and salinity concentration to investigate the correlation of parameters, which are used to the model applications in order to disposal saltwater intrusion. The data of groundwater levels, pumping capacity and hydrogeological data to were collected to build an integrated numerical model. Firstly, we will collect the information of layered aquifer and the data of hydrological parameters to build the groundwater numerical model at Pingtung Plain, and identify the amount of the groundwater which flow into the sea. In order to deal with the future climate change conditions or extreme weather conditions, we will consider the recharge with groundwater model to improve the seawater intrusion problem. The integrated numerical model which describes that seawater intrusion to deep confined aquifers and shallow unsaturated aquifers. Secondly, we will use the above model to investigate the weights influenced by different factors to the amount area of seawater intrusion, and predict the salinity concentration distribution of evaluation at coastal area of Pingtung Plain. Finally, we will simulate groundwater recharge/ injection at the coastal

  11. The major-ion composition of Carboniferous seawater

    Science.gov (United States)

    Holt, Nora M.; García-Veigas, Javier; Lowenstein, Tim K.; Giles, Peter S.; Williams-Stroud, Sherilyn

    2014-06-01

    The major-ion chemistry (Na+, Mg2+, Ca2+, K+, SO42-, and Cl-) of Carboniferous seawater was determined from chemical analyses of fluid inclusions in marine halites, using the cryo scanning electron microscopy (Cryo-SEM) X-ray energy-dispersive spectrometry (EDS) technique. Fluid inclusions in halite from the Mississippian Windsor and Mabou Groups, Shubenacadie Basin, Nova Scotia, Canada (Asbian and Pendleian Substages, 335.5-330 Ma), and from the Pennsylvanian Paradox Formation, Utah, USA, (Desmoinesian Stage 309-305 Ma) contain Na+-Mg2+-K+-Ca2+-Cl- brines, with no measurable SO42-, which shows that the Carboniferous ocean was a “CaCl2 sea”, relatively enriched in Ca2+ and low in SO42- with equivalents Ca2+ > SO42- + HCO3-. δ34S values from anhydrite in the Mississippian Shubenacadie Basin (13.2-14.0 ‰) and the Pennsylvanian Paradox Formation (11.2-12.6 ‰) support seawater sources. Br in halite from the Shubenacadie Basin (53-111 ppm) and the Paradox Basin (68-147 ppm) also indicate seawater parentages. Carboniferous seawater, modeled from fluid inclusions, contained ∼22 mmol Ca2+/kg H2O (Mississippian) and ∼24 mmol Ca2+/kg H2O (Pennsylvanian). Estimated sulfate concentrations are ∼14 mmol SO42-/kg H2O (Mississippian), and ∼12 mmol SO42-/kg H2O (Pennsylvanian). Calculated Mg2+/Ca2+ ratios are 2.5 (Mississippian) and 2.3 (Pennsylvanian), with an estimated range of 2.0-3.2. The fluid inclusion record of seawater chemistry shows a long period of CaCl2 seas in the Paleozoic, from the Early Cambrian through the Carboniferous, when seawater was enriched in Ca2+ and relatively depleted in SO42-. During this ∼200 Myr interval, Ca2+ decreased and SO42- increased, but did not cross the Ca2+-SO42- chemical divide to become a MgSO4 sea (when SO42- in seawater became greater than Ca2+) until the latest Pennsylvanian or earliest Permian (∼309-295 Ma). Seawater remained a MgSO4 sea during the Permian and Triassic, for ∼100 Myr. Fluid inclusions also record

  12. Radiolytic removal of trihalomethane in chlorinated seawater

    International Nuclear Information System (INIS)

    Rajamohan, R.; Rajesh, Puspalata; Venugopalan, V.P.; Rangarajan, S.; Natesan, Usha

    2015-01-01

    Biofouling is one of the major operational problems in seawater cooling systems. It is controlled by application of chlorine based biocides in the range of 0.5-2.0 mg L -1 . The bromide in seawater reacts with the added chlorine and forms hypobromous acid. The brominated residual biocides react with natural organic matter present in the seawater, resulting in the formation of trihalomethanes (THM) such as bromoform (CHBr 3 ), dibromochloromethane (CHBr 2 Cl) bromodichloromethane (CHBrCl 2 ). Though THMs represent a small fraction of the added chlorine, they are relatively more persistent than residual chlorine, and hence pose a potential hazard to marine life because of their reported mutagenicity. There have been few reports on removal of THMs from chlorinated seawater. In this work, the efficacy of gamma irradiation technique for the removal of THMs from chlorine-dosed seawater was investigated. Experiments were carried out using seawater collected from Kalpakkam. Irradiation study was conducted in chlorinated (1, 3, and 5 mg L -1 of Cl 2 ) seawater by applying various dosages (0.4-5.0 kGy) of gamma radiation using a 60 Co Gamma Chamber 5000. Bromoform showed a faster rate of degradation as compared to other halocarbons like bromodichloromethane and dibromochloromethane. This shows the change in total THM concentration with variation in the radiation dose and initial Cl 2 dosing. When the percentage degradation of all the three trihalomethane species was compared with applied doses, it was found that the maximum reduction occurred at a dose of 2.5 kGy. The reduction was almost similar for all the three doses (1, 3, 5 ppm of Cl 2 ) used for chlorination. With a further increase in radiation dose to 5.0 kGy, a slight increase in reduction was observed

  13. Multi-elemental determination of trace elements in deep seawater by inductively coupled plasma mass spectrometry with resin preconcentration

    International Nuclear Information System (INIS)

    Sumida, Takashi; Nakazato, Tetsuya; Tao, Hiroaki

    2003-01-01

    A miniaturized column (ca. 3 mm i.d., 40 mm length), packed with a chelating resin (0.2 g) with iminodiacetic acid groups (Muromac A-1), was tested for the preconcentration of trace elements in seawater. After preconcentration, the column was washed with ammonium acetate buffer (pH 5.5) and water to remove the major elements, such as Ca and Mg, and was then eluted with 4 ml of 2 mol l -1 nitric acid. Twenty-six trace elements were determined by inductively coupled plasma mass spectrometry and inductively coupled plasma emission spectrometry. The necessary volume of the seawater sample was only 200 ml. The recoveries for most of the elements tested were over 90%, although those for Al, V and Th were around 70%. The trueness and precision were evaluated by analyzing a standard reference material of seawater (NASS-4, NRC Canada). The observed values obtained with the present method showed good agreement with the certified values. The present method was also applied to deep seawater samples collected at Muroto, Japan. A difference in the rare earth element pattern, especially the Ce anomaly, between the deep seawater sample and the surface seawater sample was observed, as well as the differences of the concentrations of many trace elements. (author)

  14. Uranium preconcentration from seawater using adsorptive membranes

    International Nuclear Information System (INIS)

    Das, Sadananda; Pandey, A.K.; Manchanda, V.K.; Athawale, A.A.

    2009-01-01

    Uranium recovery from bio-aggressive but lean feed like seawater is a challenging problem as it requires in situ preconcentration of uranium in presence of huge excess of competing ions with fast sorption kinetics. In our laboratory, widely used amidoxime membrane (AO-membrane) was evaluated for uranium sorption under seawater conditions. This study indicated that AO-membrane was inherently slow because of the complexation chemistry involved in transfer of U(VI) from (UO 2 (CO 3 ) 3 ) 4 - to AO sites in membrane. In order to search better options, several chemical compositions of membrane were scanned for their efficacy for uranium preconcentration from seawater, and concluded that EGMP-membrane offers several advantages over AO-membrane. In this paper, the comparison of EGMP-membrane with AO-membrane for uranium sorption under seawater conditions has been reviewed. (author)

  15. Radionuclides in sediments and seawater at Rongelap Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V.E.; Robison, W.L.; Eagle, R.J.; Brunk, J.L.

    1998-03-01

    The present concentrations and distributions of long-lived, man-made radionuclides in Rongelap Atoll lagoon surface sediments, based on samples collected and analyzed in this report. The radionuclides were associated with debris generated with the 1954 Bravo thermonuclear test at Bikini Atoll. Presently, only {sup 90}Sr and the transuranic radionuclides are found associated with the surface sediments in any quantity. Other radionuclides, including {sup 60}Co and {sup 137} Cs, are virtually absent and have either decayed or migrated from the deposits to the overlying seawater. Present inventories of {sup 241}Am and {sup 249+240}Pu in the surface layer at Rongelap are estimated to be 3% of the respective inventories in surface sediments from Bikini Atoll. There is a continuous slow release of the transuranics from the sediments back to the water column. The inventories will only slowly change with time unless the chemical-physical processes that now regulate this release to the water column are changed or altered.

  16. Detection and quantification of natural contaminants of wine by gas chromatography-differential ion mobility spectrometry (GC-DMS).

    Science.gov (United States)

    Camara, Malick; Gharbi, Nasser; Lenouvel, Audrey; Behr, Marc; Guignard, Cédric; Orlewski, Pierre; Evers, Danièle

    2013-02-06

    Rapid and direct, in situ headspace screening for odoriferous volatile organic compounds (VOCs) present in fresh grapes and in wines is a very promising method for quality control because the economic value of a wine is closely related to its aroma. Long used for the detection of VOCs in complex mixtures, miniature differential ion mobility spectrometry (DMS) seems therefore adequate for in situ trace detection of many kinds of VOCs of concern appearing in the headspace of selected foodstuffs. This work aims at a rapid detection, identification, and quantification of some natural and volatile contaminants of wine such as geosmin, 2-methylisoborneol (2-MIB), 1-octen-3-ol, 1-octen-3-one, and pyrazines (2-isopropyl-3-methoxypyrazine, IPMP, and 3-isobutyl-2-methoxypyrazine, IBMP). In the present study, these compounds were spiked at a known concentration in wine and analyzed with a hyphenated trap-GC-DMS device. The detection of all target compounds at concentrations below the human olfactory threshold was demonstrated.

  17. An Earth-Abundant Catalyst-Based Seawater Photoelectrolysis System with 17.9% Solar-to-Hydrogen Efficiency.

    Science.gov (United States)

    Hsu, Shao-Hui; Miao, Jianwei; Zhang, Liping; Gao, Jiajian; Wang, Hongming; Tao, Huabing; Hung, Sung-Fu; Vasileff, Anthony; Qiao, Shi Zhang; Liu, Bin

    2018-05-01

    The implementation of water splitting systems, powered by sustainable energy resources, appears to be an attractive strategy for producing high-purity H 2 in the absence of the release of carbon dioxide (CO 2 ). However, the high cost, impractical operating conditions, and unsatisfactory efficiency and stability of conventional methods restrain their large-scale development. Seawater covers 70% of the Earth's surface and is one of the most abundant natural resources on the planet. New research is looking into the possibility of using seawater to produce hydrogen through electrolysis and will provide remarkable insight into sustainable H 2 production, if successful. Here, guided by density functional theory (DFT) calculations to predict the selectivity of gas-evolving catalysts, a seawater-splitting device equipped with affordable state-of-the-art electrocatalysts composed of earth-abundant elements (Fe, Co, Ni, and Mo) is demonstrated. This device shows excellent durability and specific selectivity toward the oxygen evolution reaction in seawater with near 100% Faradaic efficiency for the production of H 2 and O 2 . Powered by a single commercial III-V triple-junction photovoltaic cell, the integrated system achieves spontaneous and efficient generation of high-purity H 2 and O 2 from seawater at neutral pH with a remarkable 17.9% solar-to-hydrogen efficiency. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. On-line purge-and-trap-gas chromatography with flame ionization detection as an alternative analytical method for dimethyl sulphide trace release from marine algae

    Energy Technology Data Exchange (ETDEWEB)

    Careri, M.; Musci, M.; Bianchi, F.; Mucchino, C. [Parma Univ., Parma (Italy). Dipt. di Chimica Generale ed Inorganica, Chimica Analitica e Chimica Fisica; Azzoni, R.; Viaroli, P. [Parma Univ., Parma (Italy). Dipt. di Scienze Ambientali

    2001-10-01

    The release of dimethyl sulphide (DMS) by the seaweed Ulva spp at trace level was studied in aqueous solutions at different salinities, temperature and light intensities. For this purpose, the purge-and-trap technique combined with gas chromatography-flame ionization detection was used. The analytical method was evaluated in terms of linearity range, limit of detection, precision and accuracy by considering 10% (w/v) and 30% (w/v) synthetic seawater as aqueous matrices. Calculation of the recovery function evidenced a matrix influence. The method of standard addition was then used for an accurate determination of DMS in synthetic seawater reproduction the matrix effect. DMS fluxes were analysed in batch cultures of Ulva spp reproducing the conditions which usually occur in the Sacca di Goro lagoon (Northern Adriatic Sea, Italy). [Italian] Il rilascio di dimetilsolfuro (DMS) in tracce da parte della macroalga Ulva spp e' stato studiato in soluzioni acquose di differente salinita' mediante la tecnica purge-and-trap accoppiata on-line alla gascromatografia con rivelazione a ionizzazione di fiamma (GC-FID). Il metodo analitico e' stato validato in termini di linearita' di risposta, di limite di rivelabilita', precisione e accuratezza considerando come matrice acqua di mare sintetica a diversa salinita' (10%0 m/v e 30%0 m/v). Il calcolo della funzione di recupero ha consentito di verificare la presenza di errori sistematici dovuti all'effetto matrice. Il metodo sviluppato e' stato quindi applicato a matrici ambientali allo scopo di verificare il rilascio di DMS da parte di Ulva spp, operando in condizioni ambientali simili a quelle che si verificano nella Sacca di Goro (Ferrara, Italia).

  19. Study of Henna (Lawsonia inermis) as Natural Corrosion Inhibitor for Aluminum Alloy in Seawater

    International Nuclear Information System (INIS)

    Nik, W B Wan; Zulkifli, F; Sulaiman, O; Samo, K B; Rosliza, R

    2012-01-01

    Commercial henna (Lawsonia inermis) was investigated to inhibit the corrosion of aluminum alloy through immersion in seawater. The aluminum alloy (5083) was prepared in size of 25mm × 25mm × 3mm. The immersion test was conducted in seawater with different concentration of henna, 100ppm, 300ppm, 500ppm for duration of 60 days. Four characterizations were performed in this study which was weight loss study, Fourier Transform Infrared (FTIR), Electrochemical Impedance Spectroscopy (EIS) and adsorption isotherm. The results indicated that henna has major constituents of lawsone which contributed to the chemisorptions or adsorption process by forming an isolation layers on the aluminum alloy surface which follows the Langmuir adsorption isotherm. It was found that the protection layer attached on metal was not permanent and precipitation occurred as the time increases. The highest inhibition efficiency was found at 88% (500ppm). This research found that henna is an excellent natural inhibitor for aluminum alloy in seawater.

  20. Development of the DMS (2) (double MS: modular simplified and medium small reactor). Plant layout and construction for the DMS

    International Nuclear Information System (INIS)

    Shizuka Hirako; Yuusuke Shimizu; Shigeru Yokouchi; Yoshinori Iimura; Kumiaki Moriya; Takahiko Hida

    2005-01-01

    Nuclear power is expected to become the main source of electric power generation in Japan for reasons of energy security and prevention of CO 2 emissions. In addition, the recent slowdown of electric power demand and the liberalization of the electric power market are accelerating medium and small sized reactor development. Under these circumstances, DMS's (modular simplified and medium small reactors) have been developed as 400MWe class LWR's supported by the Japan Atomic Power Company. In the development of medium and small sized reactors, the most important point is how to overcome the scale demerits. To this end, we have pursued not only the simplification of systems and equipment but also the standardization of layout and construction. The main technical feature of DMS's is the adoption of a natural circulation reactor with short length fuel. Short length fuel enables the reduction of RPV height as well as construction volume of the PCV and building volume. A natural circulation reactor has considerable rationalizing effects such as the elimination of re-circulation pumps and their drive power source. By applying simplified systems and equipment, a rationalized layout and construction method are adopted. To improve the construct ability by means of modular construction methods, steel containment is applied. The PCV size is reduced to 17m in diameter and 24m in height by applying a dish-shaped drywell and eccentric RPV arrangement. By applying a compact PCV and concentrated equipment arrangement in building, it can be confirmed that the ratio of building volume per unit power is equivalent to that of existing large sized ABWRs. Furthermore, a steel plate reinforced concrete structure (SC structure) is applied to the building layout. The application of the compact PCV (steel containment) and the SC structure makes it easier to apply a large-scale module, such as an integrated steel containment and SC structure module, and an integrated multi-layer BM (building

  1. Cerebellum neurotransmission during postnatal development: [Pt(O,O'-acac)(γ-acac)(DMS)] vs cisplatin and neurotoxicity.

    Science.gov (United States)

    Piccolini, Valeria Maria; Esposito, Alessandra; Dal Bo, Veronica; Insolia, Violetta; Bottone, Maria Grazia; De Pascali, Sandra Angelica; Fanizzi, Francesco Paolo; Bernocchi, Graziella

    2015-02-01

    Several chemotherapeutic drugs are known to cause neurotoxicity. Platinum-based agents in use or in clinical trials display neurotoxic potential accompanied by neurological complications; recent studies have identified a large number of behavioural issues in paediatric oncology patients. To understand the toxicity of platinum drugs at the molecular and cellular levels, this study compares the possible cytotoxic effects of an older platinum compound, cisplatin and a new platinum compound, [Pt(O,O'-acac)(γ-acac)(DMS)], on the CNS of postnatally developing rats, which is much more vulnerable to injury than the CNS of adult rats. Since several drugs interact with neurotransmitters during neuronal maturation, we performed immunostainings with antibodies raised against markers of glutamate and GABA, the major neurotransmitters in the cerebellum. After a single injection of cisplatin at postnatal day 10 (PD10), the labelling of Purkinje cells with the neurotransmitter markers evidenced alterations between PD11 and PD30, i.e. atrophy of the dendrite tree, changes in the distribution of synaptic contacts of parallel and climbing fibres, delay in the elimination of transient synapses on cell soma and severely impaired pinceau formation at the axon hillock. After treatment with [Pt(O,O'-acac)(γ-acac)(DMS)], the sole relevant change concerned the timing of climbing fibres elimination; the transient synapses disappearance on the Purkinje cell soma was delayed in some cells; instead, the growth of Purkinje cell dendrite tree was normal as was the formation of inhibitory synaptic contacts on these neurons. These findings add new evidence not only on the lower neurotoxicity of [Pt(O,O'-acac)(γ-acac)(DMS)] vs cisplatin but also on the involvement of neurotransmitters and relative synaptic connections in the maturation of central nerve tissue. Copyright © 2014 ISDN. Published by Elsevier Ltd. All rights reserved.

  2. Primary biodegradation of petroleum hydrocarbons in seawater

    Energy Technology Data Exchange (ETDEWEB)

    Comber, M.I.H.; Den Haan, K.H.; Djemel, N.; Eadsforth, C.V.; King, D.; Paumen, M.L.; Parkerton, T.; Dmytrasz, B.

    2012-12-15

    This report describes primary biodegradation experiments performed to determine the persistence of higher molecular weight petroleum hydrocarbons in seawater. Results from the biodegradation experiments show that the majority of tested petroleum hydrocarbons have half-lives in seawater less than 60 days.

  3. Seawater-cultured Botryococcus braunii for efficient hydrocarbon extraction.

    Directory of Open Access Journals (Sweden)

    Kenichi Furuhashi

    Full Text Available As a potential source of biofuel, the green colonial microalga Botryococcus braunii produces large amounts of hydrocarbons that are accumulated in the extracellular matrix. Generally, pretreatment such as drying or heating of wet algae is needed for sufficient recoveries of hydrocarbons from B. braunii using organic solvents. In this study, the Showa strain of B. braunii was cultured in media derived from the modified Chu13 medium by supplying artificial seawater, natural seawater, or NaCl. After a certain period of culture in the media with an osmotic pressure corresponding to 1/4-seawater, hydrocarbon recovery rates exceeding 90% were obtained by simply mixing intact wet algae with n-hexane without any pretreatments and the results using the present culture conditions indicate the potential for hydrocarbon milking.Seawater was used for efficient hydrocarbon extraction from Botryococcus braunii. The alga was cultured in media prepared with seawater or NaCl. Hydrocarbon recovery rate exceeding 90% was obtained without any pretreatment.

  4. Biofouling control of industrial seawater cooling towers

    KAUST Repository

    Albloushi, Mohammed

    2017-11-01

    The use of seawater in cooling towers for industrial applications has much merit in the Gulf Cooperation Council countries due to the scarcity and availability of fresh water. Seawater make-up in cooling towers is deemed the most feasible because of its unlimited supply in coastal areas. Such latent-heat removal with seawater in cooling towers is several folds more efficient than sensible heat extraction via heat exchangers. Operational challenges such as scaling, corrosion, and biofouling are a major challenge in conventional cooling towers, where the latter is also a major issue in seawater cooling towers. Biofouling can significantly hamper the efficiency of cooling towers. The most popular methods used in cooling treatment to control biofouling are disinfection by chlorination. However, the disadvantages of chlorination are formation of harmful disinfection byproducts in the presence of high organic loading and safety concerns in the storage of chlorine gas. In this study, the research focuses on biofouling control in seawater cooling towers by investigating two different approaches. The first strategy addresses the use of alternative oxidants (i.e. ozone micro-bubbles and chlorine dioxide) in treatment of cooling towers. The second strategy investigates removing nutrients in seawater using granular activated carbon filter column and ultrafiltration to prevent the growth of microorganisms. Laboratory bench-scale tests in terms of temperature, cycle of concentration, dosage, etc. indicated that, at lower oxidant dosages (total residual oxidant (TRO) equivalent = 0.1 mg/l Cl2), chlorine dioxide had a better disinfection effect than chlorine and ozone. The performance of oxidizing biocides at pilot scale, operating at assorted conditions, showed that for the disinfectants tested, ozone could remove 95 % bioactivity of total number of bacteria and algae followed by chlorine dioxide at 85%, while conventional chlorine dosing only gave 60% reduction in bioactivities

  5. Biological control of short-term variations in the concentration of DMSP and DMS during a Phaeocystis spring bloom

    NARCIS (Netherlands)

    van Duyl, FC; Gieskes, WWC; Kop, AJ; Lewis, WE

    1998-01-01

    In the spring of 1995. short-term variations in the concentration of particulate and dissolved dimethylsulfoniopropionate (DMSP) and dimethylsulfide (DMS) were monitored in the western Wadden Sea, a shallow coastal region in open connection with the North Sea. Significant correlations were found

  6. Influences of Scavenging and Removal of Surfactants by Bubble Processing on Primary Marine Aerosol Production from North Atlantic Seawater

    Science.gov (United States)

    Duplessis, P.; Chang, R.; Frossard, A. A.; Keene, W. C.; Maben, J. R.; Long, M. S.; Beaupre, S. R.; Kieber, D. J.; Kinsey, J. D.; Zhu, Y.; Lu, X.; Bisgrove, J.

    2017-12-01

    Primary marine aerosol particles (PMA) are produced by bursting bubbles from breaking waves at the air-sea interface and significantly modulate atmospheric chemical transformations and cloud properties. Surfactants in bulk seawater rapidly (seconds) adsorb onto fresh bubble surfaces forming organic films that influence size, rise velocity, bursting behavior, and associated PMA emissions. During a cruise on the R/V Endeavor in September and October 2016, PMA production from biologically productive and oligotrophic seawater was investigated at four stations in the western North Atlantic Ocean. PMA were produced in a high-capacity generator via turbulent mixing of seawater and clean air in a Venturi nozzle. When the flow of fresh seawater through the generator was turned off, surfactant depletion via bubble processing resulted in greater PMA mass production efficiencies per unit air detrained but had no consistent influence on number production efficiencies. The greater (factor of 3) production efficiencies of organic matter associated with PMA generated with the Venturi relative to those generated with frits during previous campaigns contributed to a faster depletion of surfactants from the seawater reservoir and corresponding divergence in response.

  7. Experimental investigation and modeling of dissolved organic carbon removal by coagulation from seawater.

    Science.gov (United States)

    Jeong, Sanghyun; Sathasivan, Arumugam; Kastl, George; Shim, Wang Geun; Vigneswaran, Saravanamuthu

    2014-01-01

    Coagulation removes colloidal matters and dissolved organic carbon (DOC) which can cause irreversible membrane fouling. However, how DOC is removed by coagulant is not well-known. Jar test was used to study the removal of hydrophobic and hydrophilic DOC fractions at various doses (0.5-8.0 mg-Fe(+3) L(-1)) of ferric chloride (FeCl3) and pH (5.0-9.0). Natural organic matter (NOM) in seawater and treated seawater were fractionated by liquid chromatography-organic carbon detector (LC-OCD). Compared to surface water, the removal of DOC in seawater by coagulation was remarkably different. Majority of DOC could be easily removed with very low coagulant dose (fraction (HB) was better removed at high pH while hydrophilic fraction (HF) was better removed at low pH. A modified model of Kastl et al. (2004) which assumed that the removal occurred by adsorption of un-dissociated compounds onto ferric hydroxide was formulated and successfully validated against the jar test data. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Solid State Sensor for Simultaneous Measurement of Total Alkalinity and pH of Seawater.

    Science.gov (United States)

    Briggs, Ellen M; Sandoval, Sergio; Erten, Ahmet; Takeshita, Yuichiro; Kummel, Andrew C; Martz, Todd R

    2017-09-22

    A novel design is demonstrated for a solid state, reagent-less sensor capable of rapid and simultaneous measurement of pH and Total Alkalinity (A T ) using ion sensitive field effect transistor (ISFET) technology to provide a simplified means of characterization of the aqueous carbon dioxide system through measurement of two "master variables": pH and A T . ISFET-based pH sensors that achieve 0.001 precision are widely used in various oceanographic applications. A modified ISFET is demonstrated to perform a nanoliter-scale acid-base titration of A T in under 40 s. This method of measuring A T , a Coulometric Diffusion Titration, involves electrolytic generation of titrant, H + , through the electrolysis of water on the surface of the chip via a microfabricated electrode eliminating the requirement of external reagents. Characterization has been performed in seawater as well as titrating individual components (i.e., OH - , HCO 3 - , CO 3 2- , B(OH) 4 - , PO 4 3- ) of seawater A T . The seawater measurements are consistent with the design in reaching the benchmark goal of 0.5% precision in A T over the range of seawater A T of ∼2200-2500 μmol kg -1 which demonstrates great potential for autonomous sensing.

  9. Design Criteria, Operating Conditions, and Nickel-Iron Hydroxide Catalyst Materials for Selective Seawater Electrolysis.

    Science.gov (United States)

    Dionigi, Fabio; Reier, Tobias; Pawolek, Zarina; Gliech, Manuel; Strasser, Peter

    2016-05-10

    Seawater is an abundant water resource on our planet and its direct electrolysis has the advantage that it would not compete with activities demanding fresh water. Oxygen selectivity is challenging when performing seawater electrolysis owing to competing chloride oxidation reactions. In this work we propose a design criterion based on thermodynamic and kinetic considerations that identifies alkaline conditions as preferable to obtain high selectivity for the oxygen evolution reaction. The criterion states that catalysts sustaining the desired operating current with an overpotential seawater-mimicking electrolyte. The catalyst was synthesized by a solvothermal method and the activity, surface redox chemistry, and stability were tested electrochemically in alkaline and near-neutral conditions (borate buffer at pH 9.2) and under both fresh seawater conditions. The Tafel slope at low current densities is not influenced by pH or presence of chloride. On the other hand, the addition of chloride ions has an influence in the temporal evolution of the nickel reduction peak and on both the activity and stability at high current densities at pH 9.2. Faradaic efficiency close to 100 % under the operating conditions predicted by our design criteria was proven using in situ electrochemical mass spectrometry. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Use of experimentally determined Henry's Law and salting-out constants for ethanol in seawater for determination of the saturation state of ethanol in coastal waters.

    Science.gov (United States)

    Willey, Joan D; Powell, Jacqueline P; Avery, G Brooks; Kieber, Robert J; Mead, Ralph N

    2017-09-01

    The Henry's law constant for ethanol in seawater was experimentally determined to be 221 ± 4 M/atm at 22 °C compared with 247 ± 6 M/atm in pure water. The salting out coefficient for ethanol was 0.13 M -1 . In seawater ln(K H ) = -(12.8 ± 0.7) + (5310 ± 197)/T where K H is in M atm -1 and temperature is in K. This plus the salting out coefficient allow calculation of K H for any estuarine or sea water between 1 and 35 °C. High concentrations of dissolved organic carbon do not affect K H values in fresh or seawater. Nearshore surface waters were usually undersaturated with respect to gas phase ethanol except when air concentrations decreased, whereas surface seawater 40 km from shore was supersaturated. The percent saturation in surface waters is driven primarily by changes in air concentrations because these change quickly (hours) and more extensively than surface water. This study allows calculation of ethanol saturation states from air and surface water concentrations which is a necessary step to define the role of surface oceans in the global biogeochemical cycling of ethanol both now and in the future as use of ethanol biofuel continues to grow. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Corrosion and Protection of Metal in the Seawater Desalination

    Science.gov (United States)

    Hou, Xiangyu; Gao, Lili; Cui, Zhendong; Yin, Jianhua

    2018-01-01

    Seawater desalination develops rapid for it can solve water scarcity efficiently. However, corrosion problem in the seawater desalination system is more serious than that in normal water. So, it is important to pay attention to the corrosion and protection of metal in seawater desalination. The corrosion characteristics and corrosion types of metal in the seawater desalination system are introduced in this paper; In addition, corrosion protect methods and main influencing factors are stated, the latest new technologies about anti-corrosion with quantum energy assisted and magnetic inhibitor are presented.

  12. Simultaneous Extraction of Lithium and Hydrogen from Seawater

    Science.gov (United States)

    2011-08-22

    N00014-10-M-0234 20126083 0001AD Dr. Pyoungho Choi University of Central Florida/Florida Solar Energy Center 1679 Clearlake Road Cocoa FL 32922-5703...South America (Bolivia and Chile), Australia, and China. There have been debates as to whether the lithium supplies would meet the surging demand...extract the lithium in seawater should be developed [1]. Seawater is also the ultimate source of hydrogen. The production of hydrogen from seawater is

  13. Comparison of the partitioning behaviours of yttrium, rare earth elements, and titanium between hydrogenetic marine ferromanganese crusts and seawater

    Science.gov (United States)

    Bau, M.; Koschinsky, A.; Dulski, P.; Hein, J.R.

    1996-01-01

    In order to evaluate details of the partitioning behaviours of Y, rare earth elements (REEs), and Ti between inorganic metal oxide surfaces and seawater, we studied the distribution of these elements in hydrogenetic marine ferromanganese (Fe-Mn) crusts from the Central Pacific Ocean. Nonphosphatized Fe-Mn crusts display shale-normalized rare earths and yttrium (REYSN) patterns (Y inserted between Dy and Ho) that are depleted in light REEs (LREEs) and which show negative anomalies for YSN, and positive anomalies for LaSN, EuSN, GdSN, and in most cases, CeSN. They show considerably smaller Y/ Ho ratios than seawater or common igneous and clastic rocks, indicating that Y and Ho are fractionated in the marine environment. Compared to P-poor crusts, REYSN patterns of phosphatized Fe-Mn crusts are similar, but yield pronounced positive YSN anomalies, stronger positive LaSN anomalies, and enrichment of the HREEs relative to the MREEs. The data suggest modification of REY during phosphatization and indicate that studies requiring primary REY distributions or isotopic ratios should be restricted to nonphosphatized (layers of) Fe-Mn crusts. Apparent bulk coefficients, KMD, describing trace metal partitioning between nonphosphatized hydrogenetic Fe-Mn crusts and seawater, are similar for Pr to Eu and decrease for Eu to Yb. Exceptionally high values of KCeD, which are similar to those of Ti, result from oxidative scavenging of Ce and support previous suggestions that Ce(IV) is a hydroxide-dominated element in seawater. Yttrium and Gd show lower KD values than their respective neighbours in the REY series. Results of modelling the exchange equilibrium between REY dissolved in seawater and REY sorbed on hydrous Fe-Mn oxides corroborate previous studies that suggested the surface complexation of REY can be approximated by their first hydroxide binding constant. Negative "anomalies" occur for stabilities of bulk surface complexes of Gd, La, and particularly Y. The differences in

  14. Present status of uranium extraction from seawater

    International Nuclear Information System (INIS)

    Kusakabe, Katsuki; Morooka, Shigeharu

    1993-01-01

    For the research on the extraction of uranium from seawater, various processes have been examined, but the most promising process is adsorption. Its key point is the performance of the adsorbent. The system as compact as possible, in which a large quantity of seawater effectively contacts with the adsorbent, must be constructed economically. As the inorganic adsorbent, titanium oxide is the best, but organic amidoxime is superior to it. The present state of the development of the adsorbent, the rate of adsorption of the adsorbenbt, the seawater uranium adsorption system and the experiment in Imari Bay are reported. (K.I.)

  15. Electrochemical formation of green rusts in deaerated seawater-like solutions

    Energy Technology Data Exchange (ETDEWEB)

    Refait, Ph., E-mail: prefait@univ-lr.fr [Laboratoire d' etude des materiaux en milieux agressifs (LEMMA), EA 3167, Universite de La Rochelle, Bat. Marie Curie, Av. Michel Crepeau, F-17 042 La Rochelle Cedex 01 (France); Fed. de Recherche en Environnement et Developpement Durable, FR CNRS 3097 (France); Nguyen, D.D. [Laboratoire d' etude des materiaux en milieux agressifs (LEMMA), EA 3167, Universite de La Rochelle, Bat. Marie Curie, Av. Michel Crepeau, F-17 042 La Rochelle Cedex 01 (France); Hue University' s College of Education, Hue (Viet Nam); Jeannin, M. [Laboratoire d' etude des materiaux en milieux agressifs (LEMMA), EA 3167, Universite de La Rochelle, Bat. Marie Curie, Av. Michel Crepeau, F-17 042 La Rochelle Cedex 01 (France); Fed. de Recherche en Environnement et Developpement Durable, FR CNRS 3097 (France); Sable, S. [Littoral, Environnement et Societe (LiENSs), UMR 6250, CNRS-Univ. La Rochelle, Bat. Marie Curie, Av. Michel Crepeau, F-17 042 La Rochelle Cedex 01 (France); Fed. de Recherche en Environnement et Developpement Durable, FR CNRS 3097 (France); Langumier, M. [Laboratoire d' etude des materiaux en milieux agressifs (LEMMA), EA 3167, Universite de La Rochelle, Bat. Marie Curie, Av. Michel Crepeau, F-17 042 La Rochelle Cedex 01 (France); Littoral, Environnement et Societe (LiENSs), UMR 6250, CNRS-Univ. La Rochelle, Bat. Marie Curie, Av. Michel Crepeau, F-17 042 La Rochelle Cedex 01 (France); Fed. de Recherche en Environnement et Developpement Durable, FR CNRS 3097 (France); Sabot, R. [Laboratoire d' etude des materiaux en milieux agressifs (LEMMA), EA 3167, Universite de La Rochelle, Bat. Marie Curie, Av. Michel Crepeau, F-17 042 La Rochelle Cedex 01 (France); Fed. de Recherche en Environnement et Developpement Durable, FR CNRS 3097 (France)

    2011-07-15

    Highlights: > Sulphated green rust could be electro-generated on carbon steel in anoxic seawater-like electrolytes. > Rust layers grown during 11 years on carbon steel in natural seawater were thoroughly characterised by {mu}-Raman spectroscopy. > The mechanism of marine corrosion of carbon steel in anoxic conditions could be specified. - Abstract: Carbon steel electrodes were polarised at a potential {approx}150 mV higher than the open circuit potential, in a deaerated seawater-like electrolyte (0.5 mol dm{sup -3} NaCl, 0.03 mol dm{sup -3} Na{sub 2}SO{sub 4}, 0.003 mol dm{sup -3} NaHCO{sub 3}). X-ray diffraction and {mu}-Raman analysis demonstrated that a layer mainly composed of GR(SO{sub 4}{sup 2-}) had grown on the steel surface. GR(SO{sub 4}{sup 2-}) was accompanied by traces of GR(CO{sub 3}{sup 2-}). Similar experiments performed in a solution composed of 0.3 mol dm{sup -3} of Na{sub 2}SO{sub 4} and 0.03 mol dm{sup -3} of NaHCO{sub 3} led to the same result. The nature of the GR forming on steel is thus mainly linked to the sulphate to carbonate concentration ratio. Finally, carbon steel coupons immersed for 11 years in the harbour of La Rochelle (Atlantic coast) were removed from seawater for analysis. The inner part of the rust layer proved to be mainly composed of magnetite, GR(SO{sub 4}{sup 2-}) and iron sulphide FeS. This definitively confirms that GR(SO{sub 4}{sup 2-}), as Fe{sub 3}O{sub 4} and FeS, can form from steel in O{sub 2}-depleted environments.

  16. Erythropoietin Pretreatment Attenuates Seawater Aspiration-Induced Acute Lung Injury in Rats.

    Science.gov (United States)

    Ji, Mu-Huo; Tong, Jian-Hua; Tan, Yuan-Hui; Cao, Zhen-Yu; Ou, Cong-Yang; Li, Wei-Yan; Yang, Jian-Jun; Peng, Y G; Zhu, Si-Hai

    2016-02-01

    Seawater drowning-induced acute lung injury (ALI) is a serious clinical condition characterized by increased alveolar-capillary permeability, excessive inflammatory responses, and refractory hypoxemia. However, current therapeutic options are largely supportive; thus, it is of great interest to search for alternative agents to treat seawater aspiration-induced ALI. Erythropoietin (EPO) is a multifunctional agent with antiinflammatory, antioxidative, and antiapoptotic properties. However, the effects of EPO on seawater aspiration-induced ALI remain unclear. In the present study, male rats were randomly assigned to the naive group, normal saline group, seawater group, or seawater + EPO group. EPO was administered intraperitoneally at 48 and 24 h before seawater aspiration. Arterial blood gas analysis was performed with a gas analyzer at baseline, 30 min, 1 h, 4 h, and 24 h after seawater aspiration, respectively. Histological scores, computed tomography scan, nuclear factor kappa B p65, inducible nitric oxide synthase, caspase-3, tumor necrosis factor-alpha, interleukin (IL)-1β, IL-6, IL-10, wet-to-dry weight ratio, myeloperoxidase activity, malondialdehyde, and superoxide dismutase in the lung were determined 30 min after seawater aspiration. Our results showed that EPO pretreatment alleviated seawater aspiration-induced ALI, as indicated by increased arterial partial oxygen tension and decreased lung histological scores. Furthermore, EPO pretreatment attenuated seawater aspiration-induced increase in the expressions of pulmonary nuclear factor kappa B p65, inducible nitric oxide synthase, caspase-3, tumor necrosis factor-alpha, IL-1β, myeloperoxidase activity, and malondialdehyde when compared with the seawater group. Collectively, our study suggested that EPO pretreatment attenuates seawater aspiration-induced ALI by down-regulation of pulmonary pro-inflammatory cytokines, oxidative stress, and apoptosis.

  17. Influence of seawater intrusion on microbial communities in groundwater.

    Science.gov (United States)

    Unno, Tatsuya; Kim, Jungman; Kim, Yumi; Nguyen, Son G; Guevarra, Robin B; Kim, Gee Pyo; Lee, Ji-Hoon; Sadowsky, Michael J

    2015-11-01

    Groundwater is the sole source of potable water on Jeju Island in the Republic of (South) Korea. Groundwater is also used for irrigation and industrial purposes, and it is severely impacted by seawater intrusion in coastal areas. Consequently, monitoring the intrusion of seawater into groundwater on Jeju is very important for health and environmental reasons. A number of studies have used hydrological models to predict the deterioration of groundwater quality caused by seawater intrusion. However, there is conflicting evidence of intrusion due to complicated environmental influences on groundwater quality. Here we investigated the use of next generation sequencing (NGS)-based microbial community analysis as a way to monitor groundwater quality and detect seawater intrusion. Pristine groundwater, groundwater from three coastal areas, and seawater were compared. Analysis of the distribution of bacterial species clearly indicated that the high and low salinity groundwater differed significantly with respect to microbial composition. While members of the family Parvularculaceae were only identified in high salinity water samples, a greater percentage of the phylum Actinobacteria was predominantly observed in pristine groundwater. In addition, we identified 48 shared operational taxonomic units (OTUs) with seawater, among which the high salinity groundwater sample shared a greater number of bacterial species with seawater (6.7%). In contrast, other groundwater samples shared less than 0.5%. Our results suggest that NGS-based microbial community analysis of groundwater may be a useful tool for monitoring groundwater quality and detect seawater intrusion. This technology may also provide additional insights in understanding hydrological dynamics. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Radiation-induced reactions of Cl-, CO32-, and Br- in seawater, - Model calculation of gamma radiolysis of seawater

    International Nuclear Information System (INIS)

    Hata, Kuniki; Hanawa, Satoshi; Kasahara, Shigeki; Muroya, Yusa; Katsumura, Yosuke

    2012-09-01

    Gamma-radiolysis of seawater has been simulated to estimate the concentrations of radiolysis products. Although gas products such as H 2 , O 2 and H 2 O 2 in irradiated pure water quickly attain the steady state with very low concentrations, the products in seawater monotonically increase with dose. It was found that H 2 is produced almost linearly with dose, and corresponding G-value was 4.4 x 10 -8 mol J -1 . As similar result was obtained from the calculation of 8 x 10 -4 mol dm -3 NaBr solution, the origin of the linear increase in seawater was attributable to be the reactions of Br - . According to the sensitivity analysis, three reactions, 1: Br - + ·OH → BrOH· - , 2: BrOH· - → Br - + ·OH, and 3: BrOH· - → Br· + OH - , determined the concentrations of the products. The presence of Cl - and HCO 3 - in seawater hardly affected the concentrations of the radiolysis products. Oxyanions derived from Cl - and Br - were not obtained at observable concentration. (authors)

  19. Lawrence Livermore Laboratory concept for uranium recovery from seawater

    International Nuclear Information System (INIS)

    Gregg, D.; Wang, F.

    1980-01-01

    The Lawrence Livermore Laboratory concept for uranium recovery from seawater involves the following process steps: (1) produce activated carbon via a coal gasification plant; (2) contact activated carbon sorbent with seawater using a settling process (no pumping of seawater); (3) vacuum activated carbon from sea floor; (4) gasify or burn activated carbon (further concentrating the uranium in the ash); (5) extract the uranium from the rich ash ore by conventional techniques. The process advantages are: (1) eliminates seawater pumping, the need for an illuent, and the need for a fresh water wash; (2) should result in much lower capital investment and regional process energy. Major process issues are: (1) uranium loading on activated carbon; (2) activated carbon modifications required to improve the sorbtion performance; (3) activated carbon particle size needed to meet system requirements; (4) minimization of sorbent losses when contacted with seawater

  20. Amnesic shellfish poisoning biotoxin detection in seawater using pure or amino-functionalized Ag nanoparticles and SERS.

    Science.gov (United States)

    Müller, Csilla; Glamuzina, Branko; Pozniak, Iva; Weber, Karina; Cialla, Dana; Popp, Jürgen; Cîntă Pînzaru, Simona

    2014-12-01

    Domoic acid (DA) biotoxin responsible for the amnesic shellfish poisoning (ASP) has been unambiguously detected in seawater in a broad range of concentration, with both pure and amino-functionalized Ag nanoparticles employed for surface enhanced Raman scattering (SERS). To achieve this, a comprehensive SERS study on DA dissolved in distilled water has been conducted. SERS of DA dissolved in seawater in concentrations ranging from 3.3 × 10(-4) to 3.3 × 10(-8) mol l(-1) exhibited specific signal, completely different to those of the corresponding DA aqueous solutions, due to the seawater interference in the overall SERS effect. In order to assess the capability of the technique as a cheaper alternative for rapid and unambiguous detection of the DA biotoxin in seawater, three detection schemes have been proposed. DA was detectable at 0.33 nmoll(-1) concentration (0.33) dissolved in distilled water and 0.033 nmol l(-1) (0.033 ppb) in seawater respectively, much lower than the admitted level by the current regulation. A solvent specific interaction of DA with the NPs was concluded, since DA aqueous solution added to Ag nanoparticles provided different SERS signal compared to that of DA directly dissolved in seawater. Employing amino-functionalized Ag nanoparticles with 4-aminothiophenol as SERS tag, SERS signal of DA on amino-AgNPs revealed significant specificity associated with the aromatic primary amine interaction of the SERS tag with DA, thus allowing DA detection in seawater at 4.16 × 10(-4) mol l(-1) concentration, much higher than in the case of pure NPs. To highlight the findings, a brief literature review to date on the DA biotoxin detection was also provided. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. [Pt(O,O’-acac)(γ-acac)(DMS)] Alters SH-SY5Y Cell Migration and Invasion by the Inhibition of Na+/H+ Exchanger Isoform 1 Occurring through a PKC-ε/ERK/mTOR Pathway

    Science.gov (United States)

    Muscella, Antonella; Vetrugno, Carla; Calabriso, Nadia; Cossa, Luca Giulio; De Pascali, Sandra Angelica; Fanizzi, Francesco Paolo; Marsigliante, Santo

    2014-01-01

    We previously showed that [Pt(O,O’-acac)(γ-acac)(DMS)] ([Pt(acac)2(DMS)]) exerted substantial cytotoxic effects in SH-SY5Y neuroblastoma cells, and decreased metalloproteases (MMPs) production and cells migration in MCF-7 breast cancer cells. The ubiquitously distributed sodium-hydrogen antiporter 1 (NHE1) is involved in motility and invasion of many solid tumours. The present study focuses on the effects of [Pt(acac)2(DMS)] in SH-SY5Y cell migration and also on the possibility that NHE1 may be involved in such effect. After sublethal [Pt(acac)2(DMS)] treatment cell migration was examined by wounding assay and cell invasion by transwell assay. NHE1 activity was measured in BCECF-loaded SH-SY5Y as the rate of Na+-dependent intracellular pH recovery in response to an acute acid pulse. Gelatin zymography for MMP-2/9 activities, Western blottings of MMPs, MAPKs, mTOR, S6 and PKCs and small interfering RNAs to PKC-ε/-δ mRNA were performed. Sublethal concentrations of [Pt(acac)2(DMS)] decreases NHE1 activity, inhibites cell migration and invasion and decreases expression and activity of MMP-2 and -9. [Pt(acac)2(DMS)] administered to SH-SY5Y cells provokes the increment of ROS, generated by NADPH oxidase, responsible for the PKC-ε and PKC-δ activation. Whilst PKC-δ activates p38/MAPK, responsible for the inhibition of MMP-2 and -9 secretion, PKC-ε activates a pathway made of ERK1/2, mTOR and S6K responsible for the inhibition of NHE1 activity and cell migration. In conclusion, we have shown a drastic impairment in tumour cell metastatization in response to inhibition of NHE1 and MMPs activities by [Pt(acac)2(DMS)] occurring through a novel mechanism mediated by PKC-δ/-ε activation. PMID:25372487

  2. [Pt(O,O'-acac)(γ-acac)(DMS)] alters SH-SY5Y cell migration and invasion by the inhibition of Na+/H+ exchanger isoform 1 occurring through a PKC-ε/ERK/mTOR Pathway.

    Science.gov (United States)

    Muscella, Antonella; Vetrugno, Carla; Calabriso, Nadia; Cossa, Luca Giulio; De Pascali, Sandra Angelica; Fanizzi, Francesco Paolo; Marsigliante, Santo

    2014-01-01

    We previously showed that [Pt(O,O'-acac)(γ-acac)(DMS)] ([Pt(acac)2(DMS)]) exerted substantial cytotoxic effects in SH-SY5Y neuroblastoma cells, and decreased metalloproteases (MMPs) production and cells migration in MCF-7 breast cancer cells. The ubiquitously distributed sodium-hydrogen antiporter 1 (NHE1) is involved in motility and invasion of many solid tumours. The present study focuses on the effects of [Pt(acac)2(DMS)] in SH-SY5Y cell migration and also on the possibility that NHE1 may be involved in such effect. After sublethal [Pt(acac)2(DMS)] treatment cell migration was examined by wounding assay and cell invasion by transwell assay. NHE1 activity was measured in BCECF-loaded SH-SY5Y as the rate of Na+-dependent intracellular pH recovery in response to an acute acid pulse. Gelatin zymography for MMP-2/9 activities, Western blottings of MMPs, MAPKs, mTOR, S6 and PKCs and small interfering RNAs to PKC-ε/-δ mRNA were performed. Sublethal concentrations of [Pt(acac)2(DMS)] decreases NHE1 activity, inhibits cell migration and invasion and decreases expression and activity of MMP-2 and -9. [Pt(acac)2(DMS)] administered to SH-SY5Y cells provokes the increment of ROS, generated by NADPH oxidase, responsible for the PKC-ε and PKC-δ activation. Whilst PKC-δ activates p38/MAPK, responsible for the inhibition of MMP-2 and -9 secretion, PKC-ε activates a pathway made of ERK1/2, mTOR and S6K responsible for the inhibition of NHE1 activity and cell migration. In conclusion, we have shown a drastic impairment in tumour cell metastatization in response to inhibition of NHE1 and MMPs activities by [Pt(acac)2(DMS)] occurring through a novel mechanism mediated by PKC-δ/-ε activation.

  3. Electrochemical and Corrosion Properties of Aluminum Brass in Seawater Desalination Environments

    Directory of Open Access Journals (Sweden)

    Hong JU

    2017-11-01

    Full Text Available The corrosion behavior and mechanism of aluminum brass (HAl77-2 in seawater desalination plant were investigated using electrochemical measurement, Scanning Electronic Microscope (SEM and Energy Dispersive X-ray spectroscopy (EDX analysis. The electrochemical results revealed that the corrosion of HAl77-2 in the desalination artificial seawater depended on chloride ion concentrations, displaying a maximum with a chloride ion concentration of 2.3 wt.%. Corrosion rate of HAl77-2 initial increased and subsequently decreased with the increasing of chloride ion concentration. Moreover, corrosion of HAl77-2 becomes more severe when temperature rises. The above results obtained by electrochemical impedance spectroscopy and potentiodynamic polarization tests were in a good agreement. The results of SEM and EDX methods showed selective localized corrosion appeared remarkably on the surface of HAl77-2.DOI: http://dx.doi.org/10.5755/j01.ms.23.4.17170

  4. Speciation and spectrophotometric determination of uranium in seawater

    Directory of Open Access Journals (Sweden)

    M. KONSTANTINOU

    2004-06-01

    Full Text Available A series of ion-exchange and extraction procedures for the separation of uranium from seawater samples and subsequent spectrophotometric determination of uranium in seawater by means of arsenazo(III is described. According to the measurements performed by means of traced samples at every stage of separation, the yield of the pre-analytical procedures is generally over 90% and the separation of uranium very selective. The mean uranium concentration in seawater samples collected from five different coastal areas in Cyprus was found to be 3.2 ± 0.2 & micro; g L-1. Uranium in seawater is stable in its hexavalent oxidation state and UO2 (CO334- is the predominant species under normal coastal conditions (pH ≥ 8, EH ≥ 0.35 mV, 1 atm and 0.03% CO2.

  5. Inhibition of Sodium Benzoate on Stainless Steel in Tropical Seawater

    International Nuclear Information System (INIS)

    Seoh, S. Y.; Senin, H. B.; Nik, W. N. Wan; Amin, M. M.

    2007-01-01

    The inhibition of sodium benzoate for stainless steel controlling corrosion was studied in seawater at room temperature. Three sets of sample have been immersed in seawater containing sodium benzoate with the concentrations of 0.3M, 0.6M and 1.0M respectively. One set of sample has been immersed in seawater without adding any sodium benzoate. It was found that the highest corrosion rate was observed for the stainless steel with no inhibitor was added to the seawater. As the concentration of sodium benzoate being increased, the corrosion rate is decreases. Results show that by the addition of 1.0M of sodium benzoate in seawater samples, it giving ≥ 90% efficiencies

  6. Documentation of the seawater intrusion (SWI2) package for MODFLOW

    Science.gov (United States)

    Bakker, Mark; Schaars, Frans; Hughes, Joseph D.; Langevin, Christian D.; Dausman, Alyssa M.

    2013-01-01

    The SWI2 Package is the latest release of the Seawater Intrusion (SWI) Package for MODFLOW. The SWI2 Package allows three-dimensional vertically integrated variable-density groundwater flow and seawater intrusion in coastal multiaquifer systems to be simulated using MODFLOW-2005. Vertically integrated variable-density groundwater flow is based on the Dupuit approximation in which an aquifer is vertically discretized into zones of differing densities, separated from each other by defined surfaces representing interfaces or density isosurfaces. The numerical approach used in the SWI2 Package does not account for diffusion and dispersion and should not be used where these processes are important. The resulting differential equations are equivalent in form to the groundwater flow equation for uniform-density flow. The approach implemented in the SWI2 Package allows density effects to be incorporated into MODFLOW-2005 through the addition of pseudo-source terms to the groundwater flow equation without the need to solve a separate advective-dispersive transport equation. Vertical and horizontal movement of defined density surfaces is calculated separately using a combination of fluxes calculated through solution of the groundwater flow equation and a simple tip and toe tracking algorithm. Use of the SWI2 Package in MODFLOW-2005 only requires the addition of a single additional input file and modification of boundary heads to freshwater heads referenced to the top of the aquifer. Fluid density within model layers can be represented using zones of constant density (stratified flow) or continuously varying density (piecewise linear in the vertical direction) in the SWI2 Package. The main advantage of using the SWI2 Package instead of variable-density groundwater flow and dispersive solute transport codes, such as SEAWAT and SUTRA, is that fewer model cells are required for simulations using the SWI2 Package because every aquifer can be represented by a single layer of cells

  7. Concentration of enteric virus indicator from seawater using granular activated carbon.

    Science.gov (United States)

    Cormier, Jiemin; Gutierrez, Miguel; Goodridge, Lawrence; Janes, Marlene

    2014-02-01

    Fecal contamination of shellfish growing seawater with enteric viruses is often associated with human outbreaks of gastroenteritis. Male specific bacteriophage MS2 is correlated with those of enteric viruses in a wide range of water environments and has been used widely as a surrogate for pathogenic waterborne viruses. Since viruses in contaminated water are usually at low levels, the development of methods to concentrate viruses from water is crucial for detection purposes. In the present study, granular activated carbon was evaluated for concentration of MS2 from artificial seawater, and different parameters of the seawater were also compared. Recovery of MS2 from warm seawater (37°C) was found to be significantly greater than from cold seawater (4 and 20°C), and even greater than from fresh water (4, 20 and 37°C); the difference between seawater and fresh water became less profound when the temperatures of both were below 37°C. Although not of statistical significance, recovery of MS2 from low salinity seawater (10 and 20 parts per thousand, ppt) was greater than from high salinity seawater (30 and 40ppt). One gram of granular activated carbon was able to extract 6-log plaque forming units (PFU) of MS2 from 500ml seawater at 37°C. This study demonstrated that granular activated carbon can concentrate an enteric virus indicator from shellfish growing seawater effectively. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. The effect of artificial seawater on SERS spectra of amino acids-Ag colloids: An experiment of prebiotic chemistry

    Science.gov (United States)

    Nascimento, Fernanda C.; Carneiro, Cristine E. A.; Santana, Henrique de; Zaia, Dimas A. M.

    2014-01-01

    The large enhancement of signal observed in surface enhanced Raman spectroscopy (SERS) could be helpful for identifying amino acids on the surface of other planets, in particular for Mars, as well as in prebiotic chemistry experiments of interaction minerals/amino acids. This paper reports the effect of several substances (NaCl, MgCl2, KBr, CaSO4, K2SO4, MgSO4, KI, NH4Cl, SrCl2, CaCl2, Na2SO4, KOH, NaOH, H3BO3) on the SERS spectra of colloid of sodium citrate-CSC and colloid of sodium borohydride-CSB. The effect of four different artificial seawaters and these artificial seawaters plus amino acids (α-Ala-alanine, Gly-glycine, Cys-cysteine, AIB-2-aminoisobutiric acid) on SERS spectra using both CSC and CSB was also studied. For CSC, the effect of water, after dilution of the colloid, was the appearance of several absorption bands belonging to sodium citrate in the SERS spectrum. In general, artificial seawaters enhanced several bands in SERS spectra using CSC and CSB and CSC was more sensitive to those artificial seawaters than CSB. The identification of Gly, α-Ala and AIB using CSC or CSB was not possible because several bands belonging to artificial seawaters, sodium citrate or sodium borohydride were enhanced. On the other hand, artificial seawaters did not interfere in the SERS spectra of Cys using CSC or CSB, although the interaction of Cys with each colloid was different. For CSC the band at 2568 cm-1 (S-H stretching) of Cys vanished and for CSB the intensity of this band decreased, indicating the -SH of Cys was bonded to Ag to form -S-Ag. Thus SERS spectroscopy could be used for Cys detection on Mars soils using Mars land rovers as well as to study the interaction between Cys and minerals in prebiotic chemistry experiments.

  9. Full utilization of silt density index (SDI) measurements for seawater pre-treatment

    KAUST Repository

    Wei, Chunhai

    2012-07-01

    In order to clarify the fouling mechanism during silt density index (SDI) measurements of seawater in the seawater reverse osmosis (SWRO) desalination process, 11 runs were conducted under constant-pressure (207kPa) dead-end filtration mode according to the standard protocol for SDI measurement, in which two kinds of 0.45μm membranes of different material and seawater samples from the Mediterranean including raw seawater and seawater pre-treated by coagulation followed by sand filtration (CSF) and coagulation followed by microfiltration (CMF) technologies were tested. Fouling mechanisms based on the constant-pressure filtration equation were fully analyzed. For all runs, only t/(V/A)∼t showed very good linearity (correlation coefficient R 2>0.99) since the first moment of the filtration, indicating that standard blocking rather than cake filtration was the dominant fouling mechanism during the entire filtration process. The very low concentration of suspended solids rejected by MF of 0.45μm in seawater was the main reason why a cake layer was not formed. High turbidity removal during filtration indicated that organic colloids retained on and/or adsorbed in membrane pores governed the filtration process (i.e., standard blocking) due to the important contribution of organic substances to seawater turbidity in this study. Therefore the standard blocking coefficient k s, i.e., the slope of t/(V/A)∼t, could be used as a good fouling index for seawater because it showed good linearity with feed seawater turbidity. The correlation of SDI with k s and feed seawater quality indicated that SDI could be reliably used for seawater with low fouling potential (SDI 15min<5) like pre-treated seawater in this study. From both k s and SDI, the order of fouling potential was raw seawater>seawater pre-treated by CSF>seawater pre-treated by CMF, indicating the better performance of CMF than CSF. © 2012 Elsevier B.V.

  10. Surface modification of commercial seawater reverse osmosis membranes by grafting of hydrophilic monomer blended with carboxylated multiwalled carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Vatanpour, Vahid, E-mail: vahidvatanpour@khu.ac.ir; Zoqi, Naser

    2017-02-28

    Highlights: • A commercial PA RO membrane was modified by grafting of hydrophilic acrylic acid. • COOH-MWCNTs were mixed in grafting layer to increase permeability and antifouling. • However, more increase of CNTs caused in reduction of flux of the membranes. • Effect of acrylic acid amount, contact time and curing time was optimized. - Abstract: In this study, modification of commercial seawater reverse osmosis membranes was carried out with simultaneous use of surface grafting and nanoparticle incorporation. Membrane grafting with a hydrophilic acrylic acid monomer and thermal initiator was used to increase membrane surface hydrophilicity. The used nanomaterial was carboxylated multiwalled carbon nanotubes (MWCNTs), which were dispersed in the grafting solution and deposited on membrane surface to reduce fouling by creating polymer brushes and hydrodynamic resistance. Effectiveness of the grafting process (formation of graft layer on membrane surface) was proved by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analyses. Increase of membrane surface hydrophilicity was approved with contact angle test. First, the grafting was performed on the membrane surfaces with different monomer concentrations, various contact times and several membrane curing times (three variables for optimization). The modified membranes were tested by a cross-flow setup using saline solution for permeability and rejection tests, and bovine serum albumin (BSA) solution for fouling test. The results showed that the modified membranes with 0.75 M of monomer, 3 min contact time and 80 min curing time in an oven at 50 °C presented the highest flux and lowest rejection decline related to the commercial reverse osmosis membrane. In the next step, the optimum grafting condition was selected and the nanotubes with different weight percentages were dispersed in the acrylic acid monomer solution. The membrane containing 0.25 wt% COOH-MWCNTs showed the

  11. Surface modification of commercial seawater reverse osmosis membranes by grafting of hydrophilic monomer blended with carboxylated multiwalled carbon nanotubes

    International Nuclear Information System (INIS)

    Vatanpour, Vahid; Zoqi, Naser

    2017-01-01

    Highlights: • A commercial PA RO membrane was modified by grafting of hydrophilic acrylic acid. • COOH-MWCNTs were mixed in grafting layer to increase permeability and antifouling. • However, more increase of CNTs caused in reduction of flux of the membranes. • Effect of acrylic acid amount, contact time and curing time was optimized. - Abstract: In this study, modification of commercial seawater reverse osmosis membranes was carried out with simultaneous use of surface grafting and nanoparticle incorporation. Membrane grafting with a hydrophilic acrylic acid monomer and thermal initiator was used to increase membrane surface hydrophilicity. The used nanomaterial was carboxylated multiwalled carbon nanotubes (MWCNTs), which were dispersed in the grafting solution and deposited on membrane surface to reduce fouling by creating polymer brushes and hydrodynamic resistance. Effectiveness of the grafting process (formation of graft layer on membrane surface) was proved by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analyses. Increase of membrane surface hydrophilicity was approved with contact angle test. First, the grafting was performed on the membrane surfaces with different monomer concentrations, various contact times and several membrane curing times (three variables for optimization). The modified membranes were tested by a cross-flow setup using saline solution for permeability and rejection tests, and bovine serum albumin (BSA) solution for fouling test. The results showed that the modified membranes with 0.75 M of monomer, 3 min contact time and 80 min curing time in an oven at 50 °C presented the highest flux and lowest rejection decline related to the commercial reverse osmosis membrane. In the next step, the optimum grafting condition was selected and the nanotubes with different weight percentages were dispersed in the acrylic acid monomer solution. The membrane containing 0.25 wt% COOH-MWCNTs showed the

  12. Concentration of uranium in seawater by flotation

    International Nuclear Information System (INIS)

    Nozaki, Toru; Yamashita, Hiroshi

    1986-01-01

    A method has been developed for the concentration of uranium in seawater by precipitation flotation-carbonate extraction-ion flotation. Uranium in seawater was coprecipitated with hydrated iron (III) oxide by adjusting the pH to 5.5 after addition of 1.0 x 10 -3 mol/l of iron (III) and agitating for 1 hr, and the precipitate was floated with 1.0 x 10 -5 mol/l of sodium oleate and 5.0 x 10 -5 mol/l of sodium lauryl sulfate by bubbling nitrogen through the seawater for 15 min. Uranium was extracted from the precipitate scum at the yield of 89 % with 100 ml of 1.8 % of ammonium carbonate solution by agitating for 2 hr, and floated with 1.2 x 10 -3 mol/l of cetylpyridinium chloride by bubbling nitrogen through the extract diluted 5-fold for 30 min in the recovery of about 100 %. The fairly selective recovery of uranium was obtained from 4 l of seawater at the yield of 87 % throughout the entire process. (author)

  13. High Precision Seawater Sr/Ca Measurements in the Florida Keys by Inductively Coupled Plasma Atomic Emission Spectrometry: Analytical Method and Implications for Coral Paleothermometry

    Science.gov (United States)

    Khare, A.; Kilbourne, K. H.; Schijf, J.

    2017-12-01

    Standard methods of reconstructing past sea surface temperatures (SSTs) with coral skeletal Sr/Ca ratios assume the seawater Sr/Ca ratio is constant. However, there is little data to support this assumption, in part because analytical techniques capable of determining seawater Sr/Ca with sufficient accuracy and precision are expensive and time consuming. We demonstrate a method to measure seawater Sr/Ca using inductively coupled plasma atomic emission spectrometry where we employ an intensity ratio calibration routine that reduces the self- matrix effects of calcium and cancels out the matrix effects that are common to both calcium and strontium. A seawater standard solution cross-calibrated with multiple instruments is used to correct for long-term instrument drift and any remnant matrix effects. The resulting method produces accurate seawater Sr/Ca determinations rapidly, inexpensively, and with a precision better than 0.2%. This method will make it easier for coral paleoclimatologists to quantify potentially problematic fluctuations in seawater Sr/Ca at their study locations. We apply our method to test for variability in surface seawater Sr/Ca along the Florida Keys Reef Tract. We are collecting winter and summer samples for two years in a grid with eleven nearshore to offshore transects across the reef, as well as continuous samples collected by osmotic pumps at four locations adjacent to our grid. Our initial analysis of the grid samples indicates a trend of decreasing Sr/Ca values offshore potentially due to a decreasing groundwater influence. The values differ by as much as 0.05 mmol/mol which could lead to an error of 1°C in mean SST reconstructions. Future work involves continued sampling in the Florida Keys to test for seasonal and interannual variability in seawater Sr/Ca, as well as collecting data from small reefs in the Virgin Islands to test the stability of seawater Sr/Ca under different geologic, hydrologic and hydrographic environments.

  14. Determination of uranium in seawater by fluorescence spectrometry

    International Nuclear Information System (INIS)

    Kawashima, Toshi; Kawakubo, Senkichi; Minegishi, Hisako.

    1984-01-01

    A Fluorescence spectrometry for the determination of uranium in seawater has been developed. Anion exchange separation of uranium from seawater followed by preparation of NaF-carbonate cake and by spectrometry for ultraviolet ray excited fluorescence of uranium on the fluoride host provide the trace determinaton of uranium at the subnano gram level. Anion exchange behavior, excitation-emission behavior of the uranium on the host and effects of foreign ions to the fluorescence have been presented. Appling the method to 1 ml of seawater 3 ppb of uranium has been determined. (author)

  15. Biologically mediated dissolution of volcanic glass in seawater

    NARCIS (Netherlands)

    Staudigel, H; Yayanos, A; Chastain, R; Davies, G.T.; Verdurmen, E.A Th; Schiffmann, P; Bourcier, R; de Baar, H.J.W.

    1998-01-01

    We studied the effects of biological mediation on the dissolution of basaltic glass in seawater. Experiments with typical seawater microbial populations were contrasted with a sterile control, and reactions were monitored chemically and isotopically. Biologically mediated experiments produce twice

  16. Neodymium isotopic variations in seawater

    Science.gov (United States)

    Piepgras, D. J.; Wasserburg, G. J.

    1980-01-01

    Direct measurement of the isotopic composition of Nd in the Atlantic agree with the Nd content in ferromanganese sediments and differ from the observed amounts in the Pacific samples. These data indicate the existence of distinctive differences in the isotopic composition of Nd in the waters of major oceans; the average values determined from seawater and ferromanganese sediments are considerably lower than in sources with oceanic mantle affinities showing that the REE in the oceans is dominated by continental sources. The Nd isotopic variations in seawater are applied to relate the residence time of Nd and mixing rates between the oceans.

  17. The Fifth German Oral Health Study (Fünfte Deutsche Mundgesundheitsstudie, DMS V) - rationale, design, and methods.

    Science.gov (United States)

    Jordan, Rainer A; Bodechtel, Constanze; Hertrampf, Katrin; Hoffmann, Thomas; Kocher, Thomas; Nitschke, Ina; Schiffner, Ulrich; Stark, Helmut; Zimmer, Stefan; Micheelis, Wolfgang

    2014-12-29

    Oral diseases rank among the most prevalent non-communicable diseases in modern societies. In Germany, oral epidemiological data show that both dental caries and periodontal diseases are highly prevalent, though significant improvements in oral health has been taking in the population within the last decades, particularly in children. It is, therefore, the aim of the Fifth German Oral Health Study (DMS V) to actualize the data on current oral health status and to gather information on oral health behavior and risk factors. In addition to current oral health monitoring, the study will also permit conclusions about trends in the development of oral health in Germany between 1989 and 2014. DMS V is a cross-sectional, multi-center, nationwide representative, socio-epidemiological study to investigate the oral health status und behavior of the German resident population in four age cohorts. Study participants are children (12-year-olds), adults (35- to 44-year-olds), young olds (65- to 74-year-olds), and old olds (75- to 100-year-olds) who are drawn from local residents' registration offices. Social-science investigation parameters concern subjective perceptions and attitudes regarding oral health and nutrition, sense of coherence, and socio-demographic data. Clinical oral parameters are tooth loss, caries and periodontitis, prosthodontic status, further developmental and acquired dental hard tissue and mucosal lesions. To ensure reproducibility, the dental investigators are trained and calibrated by experts and multiple reliability checks are performed throughout the field phase. Statistical analyses are calculated according to a detailed statistical analysis plan. The DMS studies first performed in 1989, 1992 and repeated in 1997 and 2005 are the only cross-sectional oral health studies conducted in Germany on a population-based national representative level. Updated prevalence and trend analyses of key oral diseases are, therefore, of major epidemiological and health

  18. New Dielectric Measurement Data to Determine the Permittivity of Seawater at 1.4313 Hz

    Science.gov (United States)

    Lang, R.; Zhou, Y.; Utku, C.; Levine, D.

    2012-01-01

    This paper describes the new measurements - made in 2010-2011 - of the dielectric constant of seawater at 1.413 GHz using a resonant cavity technique. The purpose of these measurements is to develop an accurate relationship concerning the dependence of the dielectric constant of seawater on temperature and salinity for use by the Aquarius inversion algorithm. Aquarius is a NASA/CONAE satellite mission launched in June of 2011 with the primary mission of measuring global sea surface salinity with a 1.413 GHz radiometer to an accuracy of 0.2 psu. A brass microwave cavity resonant at 1.413 GHz has been used to measure the dielectric constant of seawater. The seawater is introduced into the cavity through a capillary glass tube having an inner diameter of 0.1 mm. The change of resonant frequency and the cavity Q value are used to determine the real and imaginary parts of the dielectric constant of seawater. Measurements are automated with Visual Basic software developed at the George Washington University. In this paper, new results from measurements made since September 2010 will be presented for salinities of 30, 35 and 38 psu with a temperature range of 0 C to 35 C in intervals of 5 C. These measurements are more accurate than earlier measurements made in 2008. The new results will be compared to the Klein-Swift (KS) and Meissner-Wentz (MW) model functions. The importance of an accurate model function will be illustrated by using these model functions to invert the Aquarius brightness temperature to retrieve the salinity values. The salinity values will be compared to co-located in situ data collected by Argo buoys.

  19. Factors affecting seawater-based pretreatment of lignocellulosic date palm residues

    DEFF Research Database (Denmark)

    Fang, Chuanji; Thomsen, Mette Hedegaard; Frankaer, Christian Grundahl

    2017-01-01

    Seawater-based pretreatment of lignocellulosic biomass is an innovative process at research stage. With respect to process optimization, factors affecting seawater-based pretreatment of lignocellulosic date palm residues were studied for the first time in this paper. Pretreatment temperature (180...... °C–210 °C), salinity of seawater (0 ppt–50 ppt), and catalysts (H2SO4, Na2CO3, and NaOH) were investigated. The results showed that pretreatment temperature exerted the largest influence on seawater-based pretreatment in terms of the enzymatic digestibility and fermentability of pretreated solids...

  20. Effects of dissolved species on radiolysis of diluted seawater

    International Nuclear Information System (INIS)

    Hata, Kuniki; Hanawa, Satoshi; Kasahara, Shigeki; Motooka, Takafumi; Tsukada, Takashi; Muroya, Yusa; Yamashita, Shinichi; Katsumura, Yosuke

    2014-01-01

    Fukushima Daiichi Nuclear Power Plants (NPPs) experienced seawater injection into the cores and fuel pools as an emergent measure after the accident. After the accident, retained water has been continuously desalinized, and subsequently the concentration of chloride ion (Cl"-) has been kept at a lower level these days. These ions in seawater are known to affect water radiolysis, which causes the production of radiolytic products, such as hydrogen peroxide (H_2O_2), molecular hydrogen (H_2) and molecular oxygen (O_2). However, the effects of dissolved ions relating seawater on the production of the stable radiolytic products are not well understood in the diluted seawater. To understand of the production behavior in diluted seawater under radiation, radiolysis calculations were carried out. Production of H_2 is effectively suppressed by diluting by up to vol10%. The concentrations of oxidants (H_2O_2 and O_2) are also suppressed by dilution of dissolved species. The effect of oxidants on corrosion of materials is thought to be low when the seawater was diluted by less than 1 vol% by water. It is also shown that deaeration is one of the effective measure to suppress the concentrations of oxidants at a lower level for any dilution conditions. (author)

  1. Sulfate was a trace constituent of Archean seawater

    DEFF Research Database (Denmark)

    Crowe, Sean Andrew; Paris, Guillaume; Katsev, Sergei

    2014-01-01

    In the low-oxygen Archean world (>2400 million years ago), seawater sulfate concentrations were much lower than today, yet open questions frustrate the translation of modern measurements of sulfur isotope fractionations into estimates of Archean seawater sulfate concentrations. In the water column...

  2. Isolation of microplastics in biota-rich seawater samples and marine organisms

    Science.gov (United States)

    Cole, Matthew; Webb, Hannah; Lindeque, Pennie K.; Fileman, Elaine S.; Halsband, Claudia; Galloway, Tamara S.

    2014-01-01

    Microplastic litter is a pervasive pollutant present in aquatic systems across the globe. A range of marine organisms have the capacity to ingest microplastics, resulting in adverse health effects. Developing methods to accurately quantify microplastics in productive marine waters, and those internalized by marine organisms, is of growing importance. Here we investigate the efficacy of using acid, alkaline and enzymatic digestion techniques in mineralizing biological material from marine surface trawls to reveal any microplastics present. Our optimized enzymatic protocol can digest >97% (by weight) of the material present in plankton-rich seawater samples without destroying any microplastic debris present. In applying the method to replicate marine samples from the western English Channel, we identified 0.27 microplastics m−3. The protocol was further used to extract microplastics ingested by marine zooplankton under laboratory conditions. Our findings illustrate that enzymatic digestion can aid the detection of microplastic debris within seawater samples and marine biota. PMID:24681661

  3. Effectiveness of KNIFC-PAN Resin in Absorbing Radiocesium in Seawater

    International Nuclear Information System (INIS)

    Nurrul Assyikeen Mohd Jaffary; Abdul Kadir Ishak; Zal Uyun Wan Mahmood; Wo, Y.M.; Norfaizal Mohamed; Mohd Tarmizi Ishak

    2016-01-01

    The effectiveness of KNiFC-PAN absorber, potassium-nickel hexacyanoferrate (II) (KNiFC) bound into modified polyacrylonitrile (PAN) have been tested for capability in absorbing radiocesium in seawater samples. The efficiency of the KNiFC-PAN were measured by the different activity of the radiocesium measured using Hyper Pure Germanium Detector (HPGe) in initial spiked seawater and eluent seawater after passed through 5 ml of KNiFC absorber. Study showed 87 % effectiveness of the KNiFC-PAN in absorbing radiocesium. Further study conducted to illustrate relation between spiked seawater and activity measured for 5 ml of KniFC passed through spiked seawater in packed column. This study suggested this relative 15L cubitainer method can be used to monitor the radiocesium in emergency situation for the fast and reliable result. (author)

  4. Confirmatory factor analysis of the Drive for Muscularity Scale-S (DMS-S) and Male Body Attitudes Scale-S (MBAS-S) among male university students in Buenos Aires.

    Science.gov (United States)

    Compte, Emilio J; Sepúlveda, Ana R; de Pellegrin, Yolanda; Blanco, Miriam

    2015-06-01

    Several studies have demonstrated that men express body dissatisfaction differently than women. Although specific instruments that address body dissatisfaction in men have been developed, only a few have been validated in Latin-American male populations. The aim of this study was to reassess the factor structure of the Spanish versions of the Drive for Muscularity Scale (DMS-S) and the Male Body Attitudes Scale (MBAS-S) in an Argentinian sample. A cross-sectional study was conducted among 423 male students to examine: the factorial structure (confirmatory factor analysis), the internal consistency reliability, and the concurrent, convergent and discriminant validity of both scales. Results replicated the two factor structures for the DMS-S and MBAS-S. Both scales showed excellent levels of internal consistency, and various measures of construct validity indicated that the DMS-S and MBAS-S were acceptable and valid instruments to assess body dissatisfaction in Argentinian males. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Greening Drylands with Seawater Easily and Naturally.

    Science.gov (United States)

    Moustafa, Khaled

    2017-03-01

    The sun and sea are inexhaustible sources of energy and water that could be used to transform drylands into more viable ecosystems. A sustainable and cost-effective approach is proposed for greening drylands and restoring wildlife and biodiversity in deserts using seawater desert-houses (or movable seawater ponds) that could offer important environmental advantages. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Perchlorate in seawater

    Energy Technology Data Exchange (ETDEWEB)

    Martinelango, P. Kalyani [Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409-1061 (United States); Tian Kang [Institute of Environmental and Human Health, Texas Tech University, Lubbock, TX 79409 (United States); Dasgupta, Purnendu K. [Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409-1061 (United States)]. E-mail: Sandyd@ttu.edu

    2006-05-10

    There has been no reliable published data on the presence of perchlorate in seawater. Seaweeds are among the most important plant life in the ocean and are good sources of iodine and have been widely used as food and nutritional supplement. Perchlorate is known to inhibit the transport of iodide by the sodium iodide symporter (NIS), present e.g., in the thyroid and mammary glands. With perchlorate being increasingly detected in drinking water, milk and various other foods, increasing the iodide intake through inexpensive natural supplements may be an attractive solution for maintaining iodine assimilation. We report here measurable concentrations of perchlorate in several samples of seawater (detectable in about half the samples analyzed). We also report the iodide and perchlorate concentrations of 11 different species of seaweed and the corresponding bioconcentration factors (BCF) for perchlorate and iodide, relative to the seawater from which they were harvested. All seaweed samples came from the same region, off the coast of Northeastern Maine. Concentrations of iodide and perchlorate in four seawater samples collected from the region near harvest time were 30 {+-} 11 and 0.16 {+-} 0.084 {mu}g l{sup -1}, respectively. Concentrations of both iodide and perchlorate varied over a wide range for different seaweed species; iodide ranging from 16 to 3134 mg kg{sup -1} and perchlorate from 0.077 to 3.2 mg kg{sup -1}. The Laminaria species had the highest iodide concentration; Laminaria digitata is the seaweed species most commonly used in the kelp tablets sold in health food stores. Our sample of L. digitata contained 3134 {+-} 15 mg iodide/kg dry weight. The BCF varied widely for different species, with Laminaria species concentrating iodide preferentially over perchlorate. The iodide BCF (BCF{sub i}) to perchlorate BCF (BCF{sub p}) quotient ranged from 0.66 to 53; L. digitata and L. saccarina having a BCF{sub i}/BCF{sub p} value of 45 and 53, respectively, far

  7. Perchlorate in seawater

    International Nuclear Information System (INIS)

    Martinelango, P. Kalyani; Tian Kang; Dasgupta, Purnendu K.

    2006-01-01

    There has been no reliable published data on the presence of perchlorate in seawater. Seaweeds are among the most important plant life in the ocean and are good sources of iodine and have been widely used as food and nutritional supplement. Perchlorate is known to inhibit the transport of iodide by the sodium iodide symporter (NIS), present e.g., in the thyroid and mammary glands. With perchlorate being increasingly detected in drinking water, milk and various other foods, increasing the iodide intake through inexpensive natural supplements may be an attractive solution for maintaining iodine assimilation. We report here measurable concentrations of perchlorate in several samples of seawater (detectable in about half the samples analyzed). We also report the iodide and perchlorate concentrations of 11 different species of seaweed and the corresponding bioconcentration factors (BCF) for perchlorate and iodide, relative to the seawater from which they were harvested. All seaweed samples came from the same region, off the coast of Northeastern Maine. Concentrations of iodide and perchlorate in four seawater samples collected from the region near harvest time were 30 ± 11 and 0.16 ± 0.084 μg l -1 , respectively. Concentrations of both iodide and perchlorate varied over a wide range for different seaweed species; iodide ranging from 16 to 3134 mg kg -1 and perchlorate from 0.077 to 3.2 mg kg -1 . The Laminaria species had the highest iodide concentration; Laminaria digitata is the seaweed species most commonly used in the kelp tablets sold in health food stores. Our sample of L. digitata contained 3134 ± 15 mg iodide/kg dry weight. The BCF varied widely for different species, with Laminaria species concentrating iodide preferentially over perchlorate. The iodide BCF (BCF i ) to perchlorate BCF (BCF p ) quotient ranged from 0.66 to 53; L. digitata and L. saccarina having a BCF i /BCF p value of 45 and 53, respectively, far greater than a simple anion exchange process

  8. The isotope composition of inorganic germanium in seawater and deep sea sponges

    Science.gov (United States)

    Guillermic, Maxence; Lalonde, Stefan V.; Hendry, Katharine R.; Rouxel, Olivier J.

    2017-09-01

    Although dissolved concentrations of germanium (Ge) and silicon (Si) in modern seawater are tightly correlated, uncertainties still exist in the modern marine Ge cycle. Germanium stable isotope systematics in marine systems should provide additional constraints on marine Ge sources and sinks, however the low concentration of Ge in seawater presents an analytical challenge for isotopic measurement. Here, we present a new method of pre-concentration of inorganic Ge from seawater which was applied to measure three Ge isotope profiles in the Southern Ocean and deep seawater from the Atlantic and Pacific Oceans. Germanium isotopic measurements were performed on Ge amounts as low as 2.6 ng using a double-spike approach and a hydride generation system coupled to a MC-ICP-MS. Germanium was co-precipitated with iron hydroxide and then purified through anion-exchange chromatography. Results for the deep (i.e. >1000 m depth) Pacific Ocean off Hawaii (nearby Loihi Seamount) and the deep Atlantic off Bermuda (BATS station) showed nearly identical δ74/70Ge values at 3.19 ± 0.31‰ (2SD, n = 9) and 2.93 ± 0.10‰ (2SD, n = 2), respectively. Vertical distributions of Ge concentration and isotope composition in the deep Southern Ocean for water depth > 1300 m yielded an average δ74/70Ge = 3.13 ± 0.25‰ (2SD, n = 14) and Ge/Si = 0.80 ± 0.09 μmol/mol (2SD, n = 12). Significant variations in δ74/70Ge, from 2.62 to 3.71‰, were measured in the first 1000 m in one station of the Southern Ocean near Sars Seamount in the Drake Passage, with the heaviest values measured in surface waters. Isotope fractionation by diatoms during opal biomineralization may explain the enrichment in heavy isotopes for both Ge and Si in surface seawater. However, examination of both oceanographic parameters and δ74/70Ge values suggest also that water mass mixing and potential contribution of shelf-derived Ge also could contribute to the variations. Combining these results with new Ge isotope data

  9. Coagulation and ultrafiltration in seawater reverse osmosis pretreatment

    NARCIS (Netherlands)

    Tabatabai, S.A.A.

    2014-01-01

    Seawater desalination is a globally expanding coastal industry with an installed capacity of over 80 million m3/day. Algal blooms pose a challenge to the operation of seawater reverse osmosis (SWRO) membranes and pre-treatment systems due to high concentrations of algal cells and algal organic

  10. Numerical Model of SO2 Scrubbing with Seawater Applied to Marine Engines

    Directory of Open Access Journals (Sweden)

    Lamas M. I.

    2016-04-01

    Full Text Available The present paper proposes a CFD model to study sulphur dioxide (SO2 absorption in seawater. The focus is on the treatment of marine diesel engine exhaust gas. Both seawater and distilled water were compared to analyze the effect of seawater alkalinity. The results indicate that seawater is more appropriate than distilled water due to its alkalinity, obtaining almost 100% cleaning efficiency for the conditions analyzed. This SO2 reduction meets the limits of SOx emission control areas (SECA when operating on heavy fuel oil. These numerical simulations were satisfactory validated with experimental tests. Such data are essential in designing seawater scrubbers and judging the operating cost of seawater scrubbing compared to alternative fuels.

  11. Development of adsorbents for recovery of uranium from seawater

    International Nuclear Information System (INIS)

    Egawa, Hiroaki; Furusaki, Shintaro.

    1987-01-01

    The largest subject for putting the extraction of uranium from seawater in practical use is the development of high performance adsorbents for uranium. In this paper, the way of thinking about the development of adsorbents for extracting uranium from seawater and the recent reports on this subject are described. Next, the research on the adsorbing capacity and adsorbing rate of the adsorbents developed so far is summarized, and the way of thinking about the evaluation of adsorbent performance which is the base of the design of a system for extracting uranium from seawater is explained, taking amidoxime type adsorbent as the example. For Japan where energy resources are scant, the uranium contained in seawater, which is estimated to be about 4.2 billion t, is the most luring important element. Uranium is contained in seawater is very low concentration of 3 ppb, and exists as anion complex salt. In 1960s, the Harwell Atomic Energy Research Establishment in UK found out that titanium oxide hydrate is the most promising as the adsorbent. Also a number of organic absorbents have been developed. In order to bring adsorbents in contact with seawater, pumping, ocean current and wave force are utilized. Adsorbents are in spherical, fiber and film forms, and held as fixed beds and fluidized beds. (Kako, I.) 48 refs

  12. Construction of a nasopharyngeal carcinoma 2D/MS repository with Open Source XML database--Xindice.

    Science.gov (United States)

    Li, Feng; Li, Maoyu; Xiao, Zhiqiang; Zhang, Pengfei; Li, Jianling; Chen, Zhuchu

    2006-01-11

    Many proteomics initiatives require integration of all information with uniformcriteria from collection of samples and data display to publication of experimental results. The integration and exchanging of these data of different formats and structure imposes a great challenge to us. The XML technology presents a promise in handling this task due to its simplicity and flexibility. Nasopharyngeal carcinoma (NPC) is one of the most common cancers in southern China and Southeast Asia, which has marked geographic and racial differences in incidence. Although there are some cancer proteome databases now, there is still no NPC proteome database. The raw NPC proteome experiment data were captured into one XML document with Human Proteome Markup Language (HUP-ML) editor and imported into native XML database Xindice. The 2D/MS repository of NPC proteome was constructed with Apache, PHP and Xindice to provide access to the database via Internet. On our website, two methods, keyword query and click query, were provided at the same time to access the entries of the NPC proteome database. Our 2D/MS repository can be used to share the raw NPC proteomics data that are generated from gel-based proteomics experiments. The database, as well as the PHP source codes for constructing users' own proteome repository, can be accessed at http://www.xyproteomics.org/.

  13. Geophysical and Seawater intrusion models to distinguish Modern and Palaeo salinity in the Central Godvari Delta, Andhra Pradesh, India

    Science.gov (United States)

    Lagudu, S.; Nandan, M. J.; Durgaprasad, M.; Gurunadha Rao, V. V. S.

    2015-12-01

    Central Godavari Delta is located in the East coast of Andhra Pradesh along Bay of Bengal. Ample surface water is made available for irrigation and aqua culture through well distributed canals drawn from Godavari River since last 150 years. Groundwater in the area is highly saline though the groundwater levels are very shallow ranging from 1 to 3 m below ground level. Integrated Electrical Resistivity Tomograms (ERT), hydrochemical (pH, TDS, Ca2+, Mg2+, K+, F-, Cl-, SO42-, NO3-, HCO3- and CO3-), isotopic (Br- and δ18O ) and density dependant solute tranport (SEAWAT) modelling studies have been carried out for four years (2006, 2007, 2014 and 2015) to identify the salinity sources and to understand the possible extent of seawater intrusion. The integration of all these data sets revealed that coarse grained sands exhibits resistivity of 4-20 Ωm forming the surface layer, clay layer exhibits Na2++ K+) and (Ca2++Mg2+), (Na+-Cl- ) vs. Ca2++Mg2+-HCO3--SO42-)) and ionic ratios ( Na2+/Cl-, SO42-/Cl-, Mg2+/Ca2+, Mg2+/Cl- and Cl-/Br) and δ18O does not reflect any modern seawater signatures. These models indicated that salinity in the shallow wells is due to dissolution of evaporitic minerals and ion exchange processes. In the pumping wells the salinity is due to upconing of entrapped sea water that belongs to Palaeo origin and wells located near the coast and mudflats is due to physical mixing of marine water. The estimated regional groundwater balance using SEAWAT model indicate significant amount of submarine groundwater discharge as outfall to the Bay of Bengal. Assuming observed hydrological conditions, no considerable advance in seawater intrusion would be expected into the delta region.

  14. Spatial distributions of and diurnal variations in low molecular weight carbonyl compounds in coastal seawater, and the controlling factors

    Energy Technology Data Exchange (ETDEWEB)

    Takeda, Kazuhiko, E-mail: takedaq@hiroshima-u.ac.jp [Graduate School of Biosphere Science, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521 (Japan); Katoh, Shinya; Mitsui, Yumi; Nakano, Shinichi [Graduate School of Biosphere Science, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521 (Japan); Nakatani, Nobutake [Graduate School of Biosphere Science, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521 (Japan); Department of Environmental and Symbiotic Sciences, Rakuno Gakuen University, 582 Bunkyodai-Midorimachi, Ebetsu, Hokkaido 069-8501 (Japan); Sakugawa, Hiroshi [Graduate School of Biosphere Science, Hiroshima University, 1-7-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8521 (Japan)

    2014-09-15

    We studied the spatial distributions of and the diurnal variations in four low molecular weight (LMW) carbonyl compounds, formaldehyde, acetaldehyde, propionaldehyde, and glyoxal, in coastal seawater. The samples were taken from the coastal areas of Hiroshima Bay, the Iyo Nada, and the Bungo Channel, western Japan. The formaldehyde, acetaldehyde, and glyoxal concentrations were higher in the northern part of Hiroshima Bay than at offshore sampling points in the Iyo Nada and the Bungo Channel. These three compounds were found at much higher concentrations in the surface water than in deeper water layers in Hiroshima Bay. It is noteworthy that propionaldehyde was not detected in any of the seawater samples, the concentrations present being lower than the detection limit (1 nanomole per liter (nM)) of the high performance liquid chromatography (HPLC) system we used. Photochemical and biological experiments were performed in the laboratory to help understand the characteristic distributions and fates of the LMW carbonyl compounds. The primary process controlling their fate in the coastal environment appears to be their biological consumption. The direct photo degradation of propionaldehyde, initiated by ultraviolet (UV) absorption, was observed, although formaldehyde and acetaldehyde were not degraded by UV irradiation. Our results suggest that the degradation of the LMW carbonyl compounds by photochemically formed hydroxyl radicals is relatively insignificant in the study area. Atmospheric deposition is a possible source of soluble carbonyl compounds in coastal surface seawater, but it may not influence the carbonyl concentrations in offshore waters. - Highlights: • Low molecular weight (LMW) carbonyl compounds in coastal seawater were determined. • Photochemical productions of LMW carbonyl compounds in seawater were observed. • LMW carbonyl compounds were largely consumed biologically. • Photochemical degradation was relatively insignificant in the study area.

  15. Spatial distributions of and diurnal variations in low molecular weight carbonyl compounds in coastal seawater, and the controlling factors

    International Nuclear Information System (INIS)

    Takeda, Kazuhiko; Katoh, Shinya; Mitsui, Yumi; Nakano, Shinichi; Nakatani, Nobutake; Sakugawa, Hiroshi

    2014-01-01

    We studied the spatial distributions of and the diurnal variations in four low molecular weight (LMW) carbonyl compounds, formaldehyde, acetaldehyde, propionaldehyde, and glyoxal, in coastal seawater. The samples were taken from the coastal areas of Hiroshima Bay, the Iyo Nada, and the Bungo Channel, western Japan. The formaldehyde, acetaldehyde, and glyoxal concentrations were higher in the northern part of Hiroshima Bay than at offshore sampling points in the Iyo Nada and the Bungo Channel. These three compounds were found at much higher concentrations in the surface water than in deeper water layers in Hiroshima Bay. It is noteworthy that propionaldehyde was not detected in any of the seawater samples, the concentrations present being lower than the detection limit (1 nanomole per liter (nM)) of the high performance liquid chromatography (HPLC) system we used. Photochemical and biological experiments were performed in the laboratory to help understand the characteristic distributions and fates of the LMW carbonyl compounds. The primary process controlling their fate in the coastal environment appears to be their biological consumption. The direct photo degradation of propionaldehyde, initiated by ultraviolet (UV) absorption, was observed, although formaldehyde and acetaldehyde were not degraded by UV irradiation. Our results suggest that the degradation of the LMW carbonyl compounds by photochemically formed hydroxyl radicals is relatively insignificant in the study area. Atmospheric deposition is a possible source of soluble carbonyl compounds in coastal surface seawater, but it may not influence the carbonyl concentrations in offshore waters. - Highlights: • Low molecular weight (LMW) carbonyl compounds in coastal seawater were determined. • Photochemical productions of LMW carbonyl compounds in seawater were observed. • LMW carbonyl compounds were largely consumed biologically. • Photochemical degradation was relatively insignificant in the study area

  16. Calcium extraction from brine water and seawater using oxalic acid

    Science.gov (United States)

    Natasha, Nadia Chrisayu; Lalasari, Latifa Hanum

    2017-01-01

    Calcium can be extracted not only from rocks but also from natural liquor such as seawater and brine water. In order to extract the calcium from seawater and brine water, oxalic acid was used in this research. Effect of variations of the volume of the oxalic acid at a constant concentration in seawater and brine water to produce calcium was investigated. The concentration of oxalic acid was 100 g/l and the variations of its volume were 2 ml, 4 ml, 6 ml, 8 ml, 10 ml, 20 ml, 30 ml, 40 ml, and 50 ml. The used seawater and brine water were firstly evaporated from 100 ml into 50 ml and then the oxalic acid was added into them with mixing to produce the calcium precipitates. The precipitates were analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM) and the filtrates were analyzed by inductively coupled plasma-optical emission spectrometry (ICP-OES). The SEM analysis showed that the precipitates from brine water were consisted of only calcium compound while from seawater sodium one was also found along with calcium compound. The XRD analysis showed that the calcium was present in the form of calcium oxalate for both seawater and brine water. The ICP-OES analysis of the filtrate from seawater precipitation showed that the its calcium content was decreased from 826.20 ppm to 0.04 ppm while from brine water, it decreased from 170.06 ppm to 1.96 ppm. These results showed that both seawater and brine water have the potential to be a raw material for calcium production.

  17. Hydraulic conductivity of some bentonites in artificial seawater

    International Nuclear Information System (INIS)

    Komine, Hideo; Murakami, Satoshi; Yasuhara, Kazuya

    2011-01-01

    A high-level radioactive waste disposal facility might be built in a coastal area in Japan from the viewpoint of feasible transportation of waste. Therefore, it is important to investigate the effects of seawater on a bentonite-based buffer. This study investigated the influence of seawater on hydraulic conductivity of three common sodium-types of bentonite and one calcium-type bentonite by the laboratory experiments. >From the results of laboratory experiment, this study discussed the influence of seawater on hydraulic conductivity of bentonites from the viewpoints of kinds of bentonite such as exchangeable-cation type and montmorillonite content and dry density of bentonite-based buffer. (author)

  18. Simulation of seawater intrusion in coastal aquifers: Some typical ...

    Indian Academy of Sciences (India)

    Springer Verlag Heidelberg #4 2048 1996 Dec 15 10:16:45

    Seawater intrusion; coastal aquifers; density-dependent flow and ... The seawater intrusion mechanism in coastal aquifers generally causes the occurrence of ... (4) The dynamic viscosity of the fluid does not change with respect to salinity and.

  19. One-dimensional self-sealing ability of bentonites in artificial seawater

    International Nuclear Information System (INIS)

    Komine, Hideo; Yasuhara, Kazuya; Murakami, Satoshi

    2009-01-01

    A high-level radioactive waste disposal facility might be built in a coastal area in Japan from the viewpoint of feasible transportation of waste. Therefore, it is important to investigate the effects of seawater on a bentonite-based buffer. This study investigated the influence of seawater on self-sealing ability of three common sodium-types of bentonite by the laboratory experiment and chemical analysis. From the results of laboratory experiment, suitable specifications were defined for a bentonite-based buffer that can withstand the effects of seawater. Furthermore, mechanism on filtration of seawater components in highly compacted bentonite was discussed by the results of chemical analysis. (author)

  20. Efficient Functionalization of Polyethylene Fibers for the Uranium Extraction from Seawater through Atom Transfer Radical Polymerization

    Energy Technology Data Exchange (ETDEWEB)

    Neti, Venkata S. [Chemical; Das, Sadananda [Chemical; Brown, Suree [Department; Janke, Christopher J. [Materials; Kuo, Li-Jung [Marine; Gill, Gary A. [Marine; Dai, Sheng [Chemical; Department; Mayes, Richard T. [Chemical

    2017-09-14

    Brush-on-brush structures are proposed as one method to overcome support effects in grafted polymers. Utilizing glycidyl methacrylate (GMA) grafted on polyethylene (PE) fibers using radiation-induced graft polymerization (RIGP) provides a hydrophilic surface on the hydrophobic PE. When integrated with atom transfer radical polymerization (ATRP), the grafting of acrylonitrile (AN) and hydroxyethyl acrylate (HEA) can be controlled and manipulated more easily than with RIGP. Poly(acrylonitrile)-co-poly(hydroxyethyl acrylate) chains were grown via ATRP on PE-GMA fibers to generate an adsorbent for the extraction of uranium from seawater. The prepared adsorbents in this study demonstrated promise (159.9 g- U/kg of adsorbent) in laboratory screening tests using a high uranium concentration brine and 1.24 g-U/Kg of adsorbent in the filtered natural seawater in 21-days. The modest capacity in 21- days exceeds previous efforts to generate brush-on-brush adsorbents by ATRP while manipulating the apparent surface hydrophilicity of the trunk material (PE).

  1. Behaviour of stainless steel in natural seawater

    OpenAIRE

    Compere, Chantal; Le Bozec, Nathalie

    1997-01-01

    In this paper, investigations performed in natural and artificial seawater on stainless steels will be presented. They concerned studies on: biofilm formation, passive layers composition, electrochemical behaviour, localised corrosion and the evolution of these different parameters as a function of ageing time. According to literature surveys, the different aspects will be discussed. Some conclusions will be drawn concerning the actual knowledge on the behaviour of stainless steels in seawater.

  2. Enhancement of Extraction of Uranium from Seawater - Final Report

    International Nuclear Information System (INIS)

    Dietz, Travis Cameron; Tsinas, Zois; Tomaszewski, Claire; Pazos, Ileana; Nigliazzo, Olga; Li, Weixing; Adel-Hadadi, Mohammad; Barkatt, Aaron; Al-Sheikhly, Mohamad

    2016-01-01

    Even at a concentration of 3 μg/L, the world's oceans contain a thousand times more uranium than currently know terrestrial sources. In order to take advantage of this stockpile, methods and materials must be developed to extract it efficiently, a difficult task considering the very low concentration of the element and the competition for extraction by other atoms in seawater such as sodium, calcium, and vanadium. The majority of current research on methods to extract uranium from seawater are vertical explorations of the grafting of amidoxime ligand, which was originally discovered and promoted by Japanese studies in the late 1980s. Our study expands on this research horizontally by exploring the effectiveness of novel uranium extraction ligands grafted to the surface of polymer substrates using radiation. Through this expansion, a greater understanding of uranium binding chemistry and radiation grafting effects on polymers has been obtained. While amidoxime-functionalized fabrics have been shown to have the greatest extraction efficiency so far, they suffer from an extensive chemical processing step which involves treatment with powerful basic solutions. Not only does this add to the chemical waste produced in the extraction process and add to the method's complexity, but it also significantly impacts the regenerability of the amidoxime fabric. The approach of this project has been to utilize alternative, commercially available monomers capable of extracting uranium and containing a carbon-carbon double bond to allow it to be grafted using radiation, specifically phosphate, oxalate, and azo monomers. The use of commercially available monomers and radiation grafting with electron beam or gamma irradiation will allow for an easily scalable fabrication process once the technology has been optimized. The need to develop a cheap and reliable method for extracting uranium from seawater is extremely valuable to energy independence, and will extend the

  3. Biofouling control of industrial seawater cooling towers

    KAUST Repository

    Al-Bloushi, Mohammed

    2017-01-01

    In this study, the research focuses on biofouling control in seawater cooling towers by investigating two different approaches. The first strategy addresses the use of alternative oxidants (i.e. ozone micro-bubbles and chlorine dioxide) in treatment of cooling towers. The second strategy investigates removing nutrients in seawater using granular activated carbon filter column and ultrafiltration to prevent the growth of microorganisms. Laboratory bench-scale tests in terms of temperature, cycle of concentration, dosage, etc. indicated that, at lower oxidant dosages (total residual oxidant (TRO) equivalent = 0.1 mg/l Cl2), chlorine dioxide had a better disinfection effect than chlorine and ozone. The performance of oxidizing biocides at pilot scale, operating at assorted conditions, showed that for the disinfectants tested, ozone could remove 95 % bioactivity of total number of bacteria and algae followed by chlorine dioxide at 85%, while conventional chlorine dosing only gave 60% reduction in bioactivities. Test results of GAC bio-filter showed that around 70 % removal of total organic carbon in the seawater feed was achieved and was effective in keeping the microbial growth to a minimum. The measured results from this study enable designers of seawater cooling towers to manage the biofouling problems when such cooling towers are extrapolated to a pilot scale.

  4. Durability of high performance concrete in seawater

    International Nuclear Information System (INIS)

    Amjad Hussain Memon; Salihuddin Radin Sumadi; Rabitah Handan

    2000-01-01

    This paper presents a report on the effects of blended cements on the durability of high performance concrete (HPC) in seawater. In this research the effect of seawater was investigated. The specimens were initially subjected to water curing for seven days inside the laboratory at room temperature, followed by seawater curing exposed to tidal zone until testing. In this study three levels of cement replacement (0%, 30% and 70%) were used. The combined use of chemical and mineral admixtures has resulted in a new generation of concrete called HPC. The HPC has been identified as one of the most important advanced materials necessary in the effort to build a nation's infrastructure. HPC opens new opportunities in the utilization of the industrial by-products (mineral admixtures) in the construction industry. As a matter of fact permeability is considered as one of the fundamental properties governing the durability of concrete in the marine environment. Results of this investigation indicated that the oxygen permeability values for the blended cement concretes at the age of one year are reduced by a factor of about 2 as compared to OPC control mix concrete. Therefore both blended cement concretes are expected to withstand in the seawater exposed to tidal zone without serious deterioration. (Author)

  5. A Survey of Tritium in Irish Seawater

    International Nuclear Information System (INIS)

    Currivan, L.; Kelleher, K.; McGinnity, P.; Wong, J.; McMahon, C.

    2013-07-01

    This report provides a comprehensive record of the study and measurements of tritium in Irish seawater undertaken by the Radiological Protection Institute of Ireland RPII. The majority of the samples analysed were found to have tritium concentrations below the limit of detection and a conservative assessment of radiation dose arising showed a negligible impact to the public. Tritium is discharged in large quantities from various nuclear facilities, and mostly in liquid form. For this reason it is included in the list of radioactive substances of interest to the OSPAR (Oslo-Paris) Convention to protect the marine environment of the North-East Atlantic. To fulfil its role within OSPAR, to provide technical support to the Irish Government, RPII carried out a project to determine the levels of tritium in seawater from around the Irish coast to supplement its routine marine monitoring programme. A total of 85 seawater samples were collected over a three year period and analysed at the RPII's laboratory. Given that the operational discharges for tritium from the nuclear fuel reprocessing plant at Sellafield, UK, are expected to increase due to current and planned decommissioning activities RPII will continue to monitor tritium levels in seawater around the Irish coast, including the Irish Sea, as part of its routine marine monitoring programme

  6. Mimicking Seawater For Culturing Marine Bacteria

    DEFF Research Database (Denmark)

    Rygaard, Anita Mac; Sonnenschein, Eva; Gram, Lone

    2015-01-01

    Only about 1% of marine bacteria have been brought into culture using traditional techniques. The purpose of this study was to investigate if mimicking the natural bacterial environment can increase culturability.We used marine substrates containing defined algal polymers or gellan gum as solidif......Only about 1% of marine bacteria have been brought into culture using traditional techniques. The purpose of this study was to investigate if mimicking the natural bacterial environment can increase culturability.We used marine substrates containing defined algal polymers or gellan gum...... as solidifying agents, and enumerated bacteria from seawater and algal exudates. We tested if culturability could be influenced by addition of quorum sensing signals (AHLs). All plates were incubated at 15°C. Bacterial counts (CFU/g) from algal exudates from brown algae were highest on media containing algal...... polymers. In general, bacteria isolated from algal exudates preferred more rich media than bacteria isolated from seawater. Overall, culturability ranged from 0.01 to 0.8% as compared to total cell count. Substitution of agar with gellan gum increased the culturability of seawater bacteria approximately...

  7. The role of humic and fulvic acids in the phototransformation of phenolic compounds in seawater

    International Nuclear Information System (INIS)

    Calza, P.; Vione, D.; Minero, C.

    2014-01-01

    Humic substances (HS) are known to act as photosensitizers toward the transformation of pollutants in the surface layer of natural waters. This study focused on the role played by HS toward the transformation of xenobiotics in seawater, with the purpose of assessing the prevailing degradation routes. Phenol was chosen as model xenobiotic and its transformation was investigated under simulated sunlight in the presence of terrestrial or marine humic and fulvic acids, in pure water at pH 8, artificial seawater (ASW) or natural seawater (NSW). The following parameters were determined: (1) the phenol degradation rate; (2) the variation in HS concentration with irradiation time; (3) the production of transformation products; (4) the influence of iron species on the transformation process. Faster transformation of phenol was observed with humic acids (HA) compared to fulvic acids (SRFA), and transformation induced by both HA and SRFA was faster in ASW than that in pure water. These observations can be explained by assuming an interplay between different competing and sometimes opposite processes, including the competition between chloride, bromide and dissolved oxygen for reaction with HS triplet states. The analysis of intermediates formed in the different matrices under study showed the formation of several hydroxylated (hydroquinone, 1,4-benzoquinone, resorcinol) and condensed compounds (2,2′-bisphenol, 4,4′-bisphenol, 4-phenoxyphenol). Although 1,4-benzoquinone was the main transformation product, formation of condensed molecules was significant with both HA and SRFA. Experiments on natural seawater spiked with HS confirmed the favored formation of condensed products, suggesting a key role of humic matter in dimerization reactions occurring in saline water. - Highlights: • Phenol transformation in seawater can be photosensitized by humic substances. • Dimeric species are peculiar intermediates formed in the process. • Phenol degradation occurred faster with

  8. The role of humic and fulvic acids in the phototransformation of phenolic compounds in seawater

    Energy Technology Data Exchange (ETDEWEB)

    Calza, P., E-mail: paola.calza@unito.it; Vione, D.; Minero, C.

    2014-09-15

    Humic substances (HS) are known to act as photosensitizers toward the transformation of pollutants in the surface layer of natural waters. This study focused on the role played by HS toward the transformation of xenobiotics in seawater, with the purpose of assessing the prevailing degradation routes. Phenol was chosen as model xenobiotic and its transformation was investigated under simulated sunlight in the presence of terrestrial or marine humic and fulvic acids, in pure water at pH 8, artificial seawater (ASW) or natural seawater (NSW). The following parameters were determined: (1) the phenol degradation rate; (2) the variation in HS concentration with irradiation time; (3) the production of transformation products; (4) the influence of iron species on the transformation process. Faster transformation of phenol was observed with humic acids (HA) compared to fulvic acids (SRFA), and transformation induced by both HA and SRFA was faster in ASW than that in pure water. These observations can be explained by assuming an interplay between different competing and sometimes opposite processes, including the competition between chloride, bromide and dissolved oxygen for reaction with HS triplet states. The analysis of intermediates formed in the different matrices under study showed the formation of several hydroxylated (hydroquinone, 1,4-benzoquinone, resorcinol) and condensed compounds (2,2′-bisphenol, 4,4′-bisphenol, 4-phenoxyphenol). Although 1,4-benzoquinone was the main transformation product, formation of condensed molecules was significant with both HA and SRFA. Experiments on natural seawater spiked with HS confirmed the favored formation of condensed products, suggesting a key role of humic matter in dimerization reactions occurring in saline water. - Highlights: • Phenol transformation in seawater can be photosensitized by humic substances. • Dimeric species are peculiar intermediates formed in the process. • Phenol degradation occurred faster with

  9. Endothelial Semaphorin 7A promotes inflammation in seawater aspiration-induced acute lung injury.

    Science.gov (United States)

    Zhang, Minlong; Wang, Li; Dong, Mingqing; Li, Zhichao; Jin, Faguang

    2014-10-28

    Inflammation is involved in the pathogenesis of seawater aspiration-induced acute lung injury (ALI). Although several studies have shown that Semaphorin 7A (SEMA7A) promotes inflammation, there are limited reports regarding immunological function of SEMA7A in seawater aspiration-induced ALI. Therefore, we investigated the role of SEMA7A during seawater aspiration-induced ALI. Male Sprague-Dawley rats were underwent seawater instillation. Then, lung samples were collected at an indicated time for analysis. In addition, rat pulmonary microvascular endothelial cells (RPMVECs) were cultured and then stimulated with 25% seawater for indicated time point. After these treatments, cells samples were collected for analysis. In vivo, seawater instillation induced lung histopathologic changes, pro-inflammation cytokines release and increased expression of SEMA7A. In vitro, seawater stimulation led to pro-inflammation cytokine release, cytoskeleton remodeling and increased monolayer permeability in pulmonary microvascular endothelial cells. In addition, knockdown of hypoxia-inducible factor (HIF)-1α inhibited the seawater induced increase expression of SEMA7A. Meanwhile, knockdown of SEMA7A by specific siRNA inhibited the seawater induced aberrant inflammation, endothelial cytoskeleton remodeling and endothelial permeability. These results suggest that SEMA7A is critical in the development of lung inflammation and pulmonary edema in seawater aspiration-induced ALI, and may be a therapeutic target for this disease.

  10. Final test report for NTCIP 1203 V2.25--dynamic message signs (DMS) as deployed by the Virginia department of transportation (VDOT).

    Science.gov (United States)

    2008-04-25

    This report presents the results of the ITS Standards Testing Program for the field testing, assessment, and evaluation of the NTCIP standards that apply in the domain of Dynamic Message Signs (DMS). Specifically, the National Transportation Communic...

  11. Fast concentration of dissolved forms of cesium radioisotopes from large seawater samples

    International Nuclear Information System (INIS)

    Jan Kamenik; Henrieta Dulaiova; Ferdinand Sebesta; Kamila St'astna; Czech Technical University, Prague

    2013-01-01

    The method developed for cesium concentration from large freshwater samples was tested and adapted for analysis of cesium radionuclides in seawater. Concentration of dissolved forms of cesium in large seawater samples (about 100 L) was performed using composite absorbers AMP-PAN and KNiFC-PAN with ammonium molybdophosphate and potassium–nickel hexacyanoferrate(II) as active components, respectively, and polyacrylonitrile as a binding polymer. A specially designed chromatography column with bed volume (BV) 25 mL allowed fast flow rates of seawater (up to 1,200 BV h -1 ). The recovery yields were determined by ICP-MS analysis of stable cesium added to seawater sample. Both absorbers proved usability for cesium concentration from large seawater samples. KNiFC-PAN material was slightly more effective in cesium concentration from acidified seawater (recovery yield around 93 % for 700 BV h -1 ). This material showed similar efficiency in cesium concentration also from natural seawater. The activity concentrations of 137 Cs determined in seawater from the central Pacific Ocean were 1.5 ± 0.1 and 1.4 ± 0.1 Bq m -3 for an offshore (January 2012) and a coastal (February 2012) locality, respectively, 134 Cs activities were below detection limit ( -3 ). (author)

  12. Influence of glacial meltwater on global seawater δ234U

    Science.gov (United States)

    Arendt, Carli A.; Aciego, Sarah M.; Sims, Kenneth W. W.; Das, Sarah B.; Sheik, Cody; Stevenson, Emily I.

    2018-03-01

    We present the first published uranium-series measurements from modern Greenland Ice Sheet (GrIS) runoff and proximal seawater, and investigate the influence of glacial melt on global seawater δ234U over glacial-interglacial (g-ig) timescales. Climate reconstructions based on closed-system uranium-thorium (U/Th) dating of fossil corals assume U chemistry of seawater has remained stable over time despite notable fluctuations in major elemental compositions, concentrations, and isotopic compositions of global seawater on g-ig timescales. Deglacial processes increase weathering, significantly increasing U-series concentrations and changing the δ234U of glacial meltwater. Analyses of glacial discharge from GrIS outlet glaciers indicate that meltwater runoff has elevated U concentrations and differing 222Rn concentrations and δ234U compositions, likely due to variations in subglacial residence time. Locations with high δ234U have the potential to increase proximal seawater δ234U. To better understand the impact of bulk glacial melt on global seawater δ234U over time, we use a simple box model to scale these processes to periods of extreme deglaciation. We account for U fluxes from the GrIS, Antarctica, and large Northern Hemisphere Continental Ice Sheets, and assess sensitivity by varying melt volumes, duration and U flux input rates based on modern subglacial water U concentrations and compositions. All scenarios support the hypothesis that global seawater δ234U has varied by more than 1‰ through time as a function of predictable perturbations in continental U fluxes during g-ig periods.

  13. Degradation of riverine dissolved organic matter by seawater bacteria

    NARCIS (Netherlands)

    Rochelle-Newall, E.J.; Pizay, M-D.; Middelburg, J.J.; Boschker, H.T.S.; Gattuso, J.P.

    2004-01-01

    The functional response of a seawater bacterial community transplanted into freshwater dissolved organic matter (DOM) was investigated together with the response of natural populations of bacteria to size-fractioned natural source water. Seawater bacteria were incubated over a period of 8 d in

  14. Corrosion of mild steel, copper and brass in crude oil / seawater mixture

    Digital Repository Service at National Institute of Oceanography (India)

    PrabhaDevi, S.; Sawant, S.S.; Wagh, A.B.

    Mild steel, copper and brass coupons were introduced in natural seawater containing varying amount of crude oil. Mild steel showed higher rate of corrosion in seawater containing oil and lower corrosion rate in natural as well as artificial seawater...

  15. Sulfur isotope variability of oceanic DMSP generation and its contributions to marine biogenic sulfur emissions.

    Science.gov (United States)

    Oduro, Harry; Van Alstyne, Kathryn L; Farquhar, James

    2012-06-05

    Oceanic dimethylsulfoniopropionate (DMSP) is the precursor to dimethylsulfide (DMS), which plays a role in climate regulation through transformation to methanesulfonic acid (MSA) and non-seasalt sulfate (NSS-SO(4)(2-)) aerosols. Here, we report measurements of the abundance and sulfur isotope compositions of DMSP from one phytoplankton species (Prorocentrum minimum) and five intertidal macroalgal species (Ulva lactuca, Ulva linza, Ulvaria obscura, Ulva prolifera, and Polysiphonia hendryi) in marine waters. We show that the sulfur isotope compositions (δ(34)S) of DMSP are depleted in (34)S relative to the source seawater sulfate by ∼1-3‰ and are correlated with the observed intracellular content of methionine, suggesting a link to metabolic pathways of methionine production. We suggest that this variability of δ(34)S is transferred to atmospheric geochemical products of DMSP degradation (DMS, MSA, and NSS-SO(4)(2-)), carrying implications for the interpretation of variability in δ(34)S of MSA and NSS-SO(4)(2-) that links them to changes in growth conditions and populations of DMSP producers rather than to the contributions of DMS and non-DMS sources.

  16. Full utilization of silt density index (SDI) measurements for seawater pre-treatment

    KAUST Repository

    Wei, Chunhai; Laborie, Sté phanie; Ben Aï m, Roger M.; Amy, Gary L.

    2012-01-01

    according to the standard protocol for SDI measurement, in which two kinds of 0.45μm membranes of different material and seawater samples from the Mediterranean including raw seawater and seawater pre-treated by coagulation followed by sand filtration (CSF

  17. XPS and NEXAFS analysis of dimethyl sulfide adsorbed on the Rh(PVP) nanoparticle surface

    International Nuclear Information System (INIS)

    Niwa, Hironori; Ogawa, Satoshi; Yagi, Shinya; Kutluk, Galif

    2010-01-01

    We have studied the adsorption reaction of dimethyl sulfide (DMS: (CH 3 ) 2 S) on the surface of Rh(PVP) nanoparticles by using AFM, XPS and NEXAFS techniques. The AFM images show the degree of dispersion of the Rh(PVP) nanoparticles depends on the amount of them. The in-situ XPS results indicate that the dissociation reaction of DMS into atomic S does not depend upon the existence of the Rh(PVP) nanoparticles. The NEXAFS results show that there is a strong chemical bonding between Rh(PVP) nanoparticle and atomic S. The ex-situ XPS results show the atomic S adsorbed on the Rh(PVP) nanoparticles partially desorb by exposing to the air. (author)

  18. Standardization of solvent extraction procedure for determination of uranium in seawater

    International Nuclear Information System (INIS)

    Sukanta Maity; Sahu, S.K.; Pandit, G.G.

    2015-01-01

    Solvent extraction procedure using ammonium pyrolidine dithiocarbamate complexing agent in methyl isobutyl ketone organic phase and acid exchange back-extraction is described for the simultaneous quantitative pre-concentration of uranium in seawater followed by its determination by differential pulse adsorptive stripping voltammetry. Solvent extraction time is optimized for extraction of uranium from seawater. Solvent extraction efficiency for uranium in seawater at different pH was carried out. The method gives a recovery of 98 ± 2 % for 400 mL sample at pH 3.0 ± 0.02, facilitating the rapid and interference free analysis of seawater samples. (author)

  19. Monitoring and modeling infiltration–recharge dynamics of managed aquifer recharge with desalinated seawater

    OpenAIRE

    Ganot, Y.; Ganot, Y.; Holtzman, R.; Weisbrod, N.; Nitzan, I.; Katz, Y.; Kurtzman, D.

    2017-01-01

    We study the relation between surface infiltration and groundwater recharge during managed aquifer recharge (MAR) with desalinated seawater in an infiltration pond, at the Menashe site that overlies the northern part of the Israeli Coastal Aquifer. We monitor infiltration dynamics at multiple scales (up to the scale of the entire pond) by measuring the ponding depth, sediment water content and groundwater levels, using pressure sensors, single-ring infiltrometers, soil senso...

  20. Dissolution of basaltic glass in seawater: Mechanism and rate

    International Nuclear Information System (INIS)

    Crovisier, J.L.; Honnorez, J.; Eberhart, J.P.

    1987-01-01

    Basaltic glasses are considered as natural analogues for nuclear waste glasses. Thermodynamic computer codes used to evaluate long term behavior of both nuclear waste and basaltic glasses require the knowledge of the dissolution mechanism of the glass network. The paper presents the results of a series of experiments designed to study the structure and chemical composition of alteration layers formed on the surface of artificial tholeiitic glass altered in artificial seawater. Experiments were performed at 60 degree C, 1 bar and 350 bars in non-renewed conditions. A natural sample from Palagonia (Sicily) has been studied by electron microscopy and comparison between natural and experimental palagonitic layers is made. The behavior of dissolved silica during experiments, and both the structure and the chemical composition of the palagonitic layers, indicate that they form by precipitation of secondary minerals from solution after a total breakdown of the glassy network, i.e., congruent dissolution of the glass. Hence the dissolution equation necessary for thermodynamic modelling of basaltic glass dissolution in seawater at low temperature must be written as a simple stoichiometric process. These experiments indicate that the transformation of glass to palagonitic material is not isovolumetric. Hence it is preferable to use Fe or Ti as conservative elements for chemical budget calculations

  1. Increased Accuracy in the Measurement of the Dielectric Constant of Seawater at 1.413 GHz

    Science.gov (United States)

    Zhou, Y.; Lang R.; Drego, C.; Utku, C.; LeVine, D.

    2012-01-01

    This paper describes the latest results for the measurements of the dielectric constant at 1.413 GHz by using a resonant cavity technique. The purpose of these measurements is to develop an accurate relationship for the dependence of the dielectric constant of sea water on temperature and salinity which is needed by the Aquarius inversion algorithm to retrieve salinity. Aquarius is the major instrument on the Aquarius/SAC-D observatory, a NASA/CONAE satellite mission launched in June of20ll with the primary mission of measuring global sea surface salinity to an accuracy of 0.2 psu. Aquarius measures salinity with a 1.413 GHz radiometer and uses a scatterometer to compensate for the effects of surface roughness. The core part of the seawater dielectric constant measurement system is a brass microwave cavity that is resonant at 1.413 GHz. The seawater is introduced into the cavity through a capillary glass tube having an inner diameter of 0.1 mm. The change of resonance frequency and the cavity Q value are used to determine the real and imaginary parts of the dielectric constant of seawater introduced into the thin tube. Measurements are automated with the help of software developed at the George Washington University. In this talk, new results from measurements made since September 2010 will be presented for salinities 30, 35 and 38 psu with a temperature range of O C to 350 C in intervals of 5 C. These measurements are more accurate than earlier measurements made in 2008 because of a new method for measuring the calibration constant using methanol. In addition, the variance of repeated seawater measurements has been reduced by letting the system stabilize overnight between temperature changes. The new results are compared to the Kline Swift and Meissner Wentz model functions. The importance of an accurate model function will be illustrated by using these model functions to invert the Aquarius brightness temperature to get the salinity values. The salinity values

  2. A paired apatite and calcite clumped isotope thermometry approach to estimating Cambro-Ordovician seawater temperatures and isotopic composition

    Science.gov (United States)

    Bergmann, Kristin D.; Finnegan, Seth; Creel, Roger; Eiler, John M.; Hughes, Nigel C.; Popov, Leonid E.; Fischer, Woodward W.

    2018-03-01

    The secular increase in δ18O values of both calcitic and phosphatic marine fossils through early Phanerozoic time suggests either that (1) early Paleozoic surface temperatures were high, in excess of 40 °C (tropical MAT), (2) the δ18O value of seawater has increased by 7-8‰ VSMOW through Paleozoic time, or (3) diagenesis has altered secular trends in early Paleozoic samples. Carbonate clumped isotope analysis, in combination with petrographic and elemental analysis, can deconvolve fluid composition from temperature effects and therefore determine which of these hypotheses best explain the secular δ18O increase. Clumped isotope measurements of a suite of calcitic and phosphatic marine fossils from late Cambrian- to Middle-late Ordovician-aged strata-the first paired fossil study of its kind-document tropical sea surface temperatures near modern temperatures (26-38 °C) and seawater oxygen isotope ratios similar to today's ratios.

  3. Construction of a nasopharyngeal carcinoma 2D/MS repository with Open Source XML Database – Xindice

    Directory of Open Access Journals (Sweden)

    Li Jianling

    2006-01-01

    Full Text Available Abstract Background Many proteomics initiatives require integration of all information with uniformcriteria from collection of samples and data display to publication of experimental results. The integration and exchanging of these data of different formats and structure imposes a great challenge to us. The XML technology presents a promise in handling this task due to its simplicity and flexibility. Nasopharyngeal carcinoma (NPC is one of the most common cancers in southern China and Southeast Asia, which has marked geographic and racial differences in incidence. Although there are some cancer proteome databases now, there is still no NPC proteome database. Results The raw NPC proteome experiment data were captured into one XML document with Human Proteome Markup Language (HUP-ML editor and imported into native XML database Xindice. The 2D/MS repository of NPC proteome was constructed with Apache, PHP and Xindice to provide access to the database via Internet. On our website, two methods, keyword query and click query, were provided at the same time to access the entries of the NPC proteome database. Conclusion Our 2D/MS repository can be used to share the raw NPC proteomics data that are generated from gel-based proteomics experiments. The database, as well as the PHP source codes for constructing users' own proteome repository, can be accessed at http://www.xyproteomics.org/.

  4. Seawater-drowning-induced acute lung injury: From molecular mechanisms to potential treatments.

    Science.gov (United States)

    Jin, Faguang; Li, Congcong

    2017-06-01

    Drowning is a crucial public safety problem and is the third leading cause of accidental fatality, claiming ~372,000 lives annually, worldwide. In near-drowning patients, acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) is one of the most common complications. Approximately 1/3 of near-drowning patients fulfill the criteria for ALI or ARDS. In the present article, the current literature of near-drowning, pathophysiologic changes and the molecular mechanisms of seawater-drowning-induced ALI and ARDS was reviewed. Seawater is three times more hyperosmolar than plasma, and following inhalation of seawater the hyperosmotic seawater may cause serious injury in the lung and alveoli. The perturbing effects of seawater may be primarily categorized into insufficiency of pulmonary surfactant, blood-air barrier disruption, formation of pulmonary edema, inflammation, oxidative stress, autophagy, apoptosis and various other hypertonic stimulation. Potential treatments for seawater-induced ALI/ARDS were also presented, in addition to suggestions for further studies. A total of nine therapeutic strategies had been tested and all had focused on modulating the over-activated immunoreactions. In conclusion, seawater drowning is a complex injury process and the exact mechanisms and potential treatments require further exploration.

  5. Seawater-drowning-induced acute lung injury: From molecular mechanisms to potential treatments

    Science.gov (United States)

    Jin, Faguang; Li, Congcong

    2017-01-01

    Drowning is a crucial public safety problem and is the third leading cause of accidental fatality, claiming ~372,000 lives annually, worldwide. In near-drowning patients, acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) is one of the most common complications. Approximately 1/3 of near-drowning patients fulfill the criteria for ALI or ARDS. In the present article, the current literature of near-drowning, pathophysiologic changes and the molecular mechanisms of seawater-drowning-induced ALI and ARDS was reviewed. Seawater is three times more hyperosmolar than plasma, and following inhalation of seawater the hyperosmotic seawater may cause serious injury in the lung and alveoli. The perturbing effects of seawater may be primarily categorized into insufficiency of pulmonary surfactant, blood-air barrier disruption, formation of pulmonary edema, inflammation, oxidative stress, autophagy, apoptosis and various other hypertonic stimulation. Potential treatments for seawater-induced ALI/ARDS were also presented, in addition to suggestions for further studies. A total of nine therapeutic strategies had been tested and all had focused on modulating the over-activated immunoreactions. In conclusion, seawater drowning is a complex injury process and the exact mechanisms and potential treatments require further exploration. PMID:28587319

  6. A field study of physico-chemical states of artificial radionuclides in seawater

    International Nuclear Information System (INIS)

    Nagaya, Yutaka; Nakamura, Kiyoshi

    1974-01-01

    The physico-chemical states of artificial radionuclides, 90 Sr, 137 Cs and 144 Ce in seawater were investigated by radiochemical analysis of filtered and unfiltered seawater. The difference of radionuclide concentrations between unfiltered and filtered seawaters was defined as the ''particulate form'' radioisotope and its ''particle ratio'' was discussed. Practically no particulate 90 Sr, greater than 0.22 μ in size, was observed in both coastal and open seawaters, but some of 137 Cs seemed to be insoluble in some circumstances, especially in coastal waters. A considerable amount of 144 Ce was found to be particulate. An estimation of the radionuclides in particulate form was made for Kashima-nada seawaters collected in 1970 to 1972, and it was shown that the possible occurrence of particulate radionuclides, greater than 0.22 μ in size, were 1% or less for 90 Sr and 6% for 137 Cs. In the coastal water, 80% of 144 Ce were seemed to be in particulate form, but in the open seawater only a few %. The influences of suspended materials to 137 Cs and 144 Ce concentration levels in seawater were not negligible and further investigations are desirable. (auth.)

  7. Adsorption and desorption of phosphate on limestone in experiments simulating seawater intrusion

    Science.gov (United States)

    The absorption and desorption of phosphorus on a large block of limestone was investigated using deionized water (DIW) and seawater. The limestone had a high affinity to adsorb phosphorus in DIW. Phosphate adsorption was significantly less in seawater, and more phosphorus was desorbed in the seawate...

  8. Organic Carbon Reduction in Seawater Reverse Osmosis (SWRO) Plants, Jeddah, Saudi Arabia

    KAUST Repository

    Alshahri, Abdullah

    2015-12-01

    Desalination is considered to be a major source of usable water in the Middle East, especially the Gulf countries which lack fresh water resources. A key and sometimes the only solution to produce high quality water in these countries is through the use of seawater reverse osmosis (SWRO) desalination technology. Membrane fouling is an economic and operational defect that impacts the performance of SWRO desalination technology. To limit this fouling phenomenon, it is important to implement the appropriate type of intake and pre-treatment system design. In this study, two types of systems were investigated, a vertical well system and a surface-water intake at a 9m depth. The purpose of this investigation is to study the impact of the different intake systems and pre-treatment stages in minimizing the concentrations of algae, bacteria, natural organic matter (NOM) and transparent exopolymer particles (TEP), in the feed water prior to pre-treatment, through the pre-treatment stages, and in the product water and concentrate. Water samples were collected from the surface seawater, the intakes (wells for site A, 9 m depth open ocean intake at site B), after the media filter, after the cartridge filter, and from the permeate and reject streams. The measured parameters included physical parameters, algae, bacteria, total organic carbon (TOC), fractions of dissolved NOM, particulate and colloidal TEP. The results of this study prove that the natural filtration and biological treatment of the seawater which occur in the aquifer matrix are very effective in improving the raw water quality to a significant degree. The results demonstrated that algae and biopolymers were 100% removed, the bacterial concentrations were significantly removed and roughly 50% or greater of TOC concentrations was eliminated by the aquifer matrix at site A. The aquifer feeding the vertical wells reduced TEP concentrations, but to differing degree. There is a slight decrease in the concentrations of

  9. Seawater infiltration effect on thermal degradation of fiber reinforced epoxy composites

    Science.gov (United States)

    Ibrahim, Mohd Haziq Izzuddin bin; Hassan, Mohamad Zaki bin; Ibrahim, Ikhwan; Rashidi, Ahmad Hadi Mohamed; Nor, Siti Fadzilah M.; Daud, Mohd Yusof Md

    2018-05-01

    Seawater salinity has been associated with the reduction of polymer structure durability. The aim of this study is to investigate the change in thermal degradation of fiber reinforced epoxy composite due to the presence of seawater. Carbon fiber, carbon/kevlar, fiberglass, and jute that reinforced with epoxy resin was laminated through hand-layup technique. Initially, these specimen was sectioned to 5×5 mm dimension, then immersed in seawater and distilled water at room temperature until it has thoroughly saturated. Following, the thermal degradation analysis using Differential Scanning Calorimetry (DSC), the thermic changes due to seawater infiltration was defined. The finding shows that moisture absorption reduces the glass transition temperature (Tg) of fiber reinforced epoxy composite. However, the glass transition temperature (Tg) of seawater infiltrated laminate composite is compareable with distilled water infiltrated laminate composite. The carbon fiber reinfored epoxy has the highest glass transition temperature out of all specimen.

  10. Intensively exploited Mediterranean aquifers: resilience to seawater intrusion and proximity to critical thresholds

    Science.gov (United States)

    Mazi, K.; Koussis, A. D.; Destouni, G.

    2014-05-01

    We investigate seawater intrusion in three prominent Mediterranean aquifers that are subject to intensive exploitation and modified hydrologic regimes by human activities: the Nile Delta, Israel Coastal and Cyprus Akrotiri aquifers. Using a generalized analytical sharp interface model, we review the salinization history and current status of these aquifers, and quantify their resilience/vulnerability to current and future seawater intrusion forcings. We identify two different critical limits of seawater intrusion under groundwater exploitation and/or climatic stress: a limit of well intrusion, at which intruded seawater reaches key locations of groundwater pumping, and a tipping point of complete seawater intrusion up to the prevailing groundwater divide of a coastal aquifer. Either limit can be reached, and ultimately crossed, under intensive aquifer exploitation and/or climate-driven change. We show that seawater intrusion vulnerability for different aquifer cases can be directly compared in terms of normalized intrusion performance curves. The site-specific assessments show that (a) the intruding seawater currently seriously threatens the Nile Delta aquifer, (b) in the Israel Coastal aquifer the sharp interface toe approaches the well location and (c) the Cyprus Akrotiri aquifer is currently somewhat less threatened by increased seawater intrusion.

  11. 60Co levels in the seawater regions

    International Nuclear Information System (INIS)

    Yoshioka, Mitsuo

    1983-01-01

    In order to assess the contribution from nuclear power facilities to the 60 Co levels in seawater regions, it is essential to grasp the background values of 60 Co. The following matters are described: 60 Co sources and the respective inputs; nuclear test fallout and nuclear power plants; the 60 Co levels in overseas countries; the 60 Co levels in Japan; the 60 Co levels from nuclear power plants in Fukui prefecture. In the seawater regions around Japan, there have been numerous instances of 60 Co detection; several pCi/kg of dry earth in sea bottom earth and about 1 pCi/kg of raw material in marine life can be considered as the background levels due to nuclear test fallout and nuclear-powered submarines. In the seawater regions of Fukui prefecture, the 60 Co levels appreciably exceeded the above background due to the nuclear power plants, which are insignificant concerning the radiation exposure of the local people. (Mori, K.)

  12. Extracting Minerals from Seawater: An Energy Analysis

    Directory of Open Access Journals (Sweden)

    Ugo Bardi

    2010-04-01

    Full Text Available The concept of recovering minerals from seawater has been proposed as a way of counteracting the gradual depletion of conventional mineral ores. Seawater contains large amounts of dissolved ions and the four most concentrated metal ones (Na, Mg, Ca, K are being commercially extracted today. However, all the other metal ions exist at much lower concentrations. This paper reports an estimate of the feasibility of the extraction of these metal ions on the basis of the energy needed. In most cases, the result is that extraction in amounts comparable to the present production from land mines would be impossible because of the very large amount of energy needed. This conclusion holds also for uranium as fuel for the present generation of nuclear fission plants. Nevertheless, in a few cases, mainly lithium, extraction from seawater could provide amounts of metals sufficient for closing the cycle of metal use in the economy, provided that an increased level of recycling can be attained.

  13. Uncertainties in Climatological Seawater Density Calculations

    Science.gov (United States)

    Dai, Hao; Zhang, Xining

    2018-03-01

    In most applications, with seawater conductivity, temperature, and pressure data measured in situ by various observation instruments e.g., Conductivity-Temperature-Depth instruments (CTD), the density which has strong ties to ocean dynamics and so on is computed according to equations of state for seawater. This paper, based on density computational formulae in the Thermodynamic Equation of Seawater 2010 (TEOS-10), follows the Guide of the expression of Uncertainty in Measurement (GUM) and assesses the main sources of uncertainties. By virtue of climatological decades-average temperature/Practical Salinity/pressure data sets in the global ocean provided by the National Oceanic and Atmospheric Administration (NOAA), correlation coefficients between uncertainty sources are determined and the combined standard uncertainties uc>(ρ>) in seawater density calculations are evaluated. For grid points in the world ocean with 0.25° resolution, the standard deviations of uc>(ρ>) in vertical profiles cover the magnitude order of 10-4 kg m-3. The uc>(ρ>) means in vertical profiles of the Baltic Sea are about 0.028kg m-3 due to the larger scatter of Absolute Salinity anomaly. The distribution of the uc>(ρ>) means in vertical profiles of the world ocean except for the Baltic Sea, which covers the range of >(0.004,0.01>) kg m-3, is related to the correlation coefficient r>(SA,p>) between Absolute Salinity SA and pressure p. The results in the paper are based on sensors' measuring uncertainties of high accuracy CTD. Larger uncertainties in density calculations may arise if connected with lower sensors' specifications. This work may provide valuable uncertainty information required for reliability considerations of ocean circulation and global climate models.

  14. Impediment to symbiosis establishment between giant clams and Symbiodinium algae due to sterilization of seawater.

    Science.gov (United States)

    Kurihara, Takeo; Yamada, Hideaki; Inoue, Ken; Iwai, Kenji; Hatta, Masayuki

    2013-01-01

    To survive the juvenile stage, giant clam juveniles need to establish a symbiotic relationship with the microalgae Symbiodinium occurring in the environment. The percentage of giant clam juveniles succeeding in symbiosis establishment ("symbiosis rate") is often low, which is problematic for seed producers. We investigated how and why symbiosis rates vary, depending on whether giant clam seeds are continuously reared in UV treated or non treated seawater. Results repeatedly demonstrated that symbiosis rates were lower for UV treated seawater than for non treated seawater. Symbiosis rates were also lower for autoclaved seawater and 0.2-µm filtered seawater than for non treated seawater. The decreased symbiosis rates in various sterilized seawater suggest the possibility that some factors helping symbiosis establishment in natural seawater are weakened owing to sterilization. The possible factors include vitality of giant clam seeds, since additional experiments revealed that survival rates of seeds reared alone without Symbiodinium were lower in sterilized seawater than in non treated seawater. In conclusion, UV treatment of seawater was found to lead to decreased symbiosis rates, which is due possibly to some adverse effects common to the various sterilization techniques and relates to the vitality of the giant clam seeds.

  15. Effects of seawater components on radiolysis of water at elevated temperature

    International Nuclear Information System (INIS)

    Wada, Yoichi; Tachibana, Masahiko; Ishida, Kazushige; Ota, Nobuyuki; Shigenaka, Naoto; Inagaki, Hiromitsu; Noda, Hiroshi

    2014-01-01

    Effects of seawater components on radiolysis of water at elevated temperature have been studied with a radiolysis model in order to evaluate influence on integrity of materials used in an ABWR. In 2011, seawater flowed into a wide part of the nuclear power plant system of the Hamaoka Nuclear Power Station Reactor No. 5 owned by Chubu Electric Power Co., Inc. after condenser tubes broke during the plant shutdown operation. The reactor water temperature was 250°C and its maximum Cl − concentration was ca. 450 ppm when seawater was mixed with reactor water. In order to clarify effects of the sea water components on radiolysis of water at elevated temperature, a radiolysis model calculation was conducted with Hitachi's radiolysis analysis code 'SIMFONY'. For the calculation, the temperature range was set from 50 to 250°C with 50°C increments and the gamma dose rate was set at 60 Gys −1 to see the effect of gamma irradiation from fuels under shutdown conditions. Concentrations of radiolytic species were calculated for 10 5 s. Dilution ratio of seawater was changed to see the effects of concentration of seawater components. Reaction rate constants of the Cl − , Br − , HCO 3 − , and SO 4 2− systems were considered. The main radiolytic species were predicted to be hydrogen and oxygen. Hydrogen peroxide of low concentration was produced in seawater-mixed water at elevated temperatures. Compared with these main products, concentrations of radiolytic products originating from chloride ion and other seawater components were found to be rather low. The dominant product among them was ClO 3 − and its concentration was found to be below 0.01ppm at 10 5 s. Then, during the plant shutdown operation, the harmful influence from radiolytic species originating from seawater components on integrity of fuel materials must be smaller than that of chloride ion which is the main ionic species in seawater. (author)

  16. Enhancement of Extraction of Uranium from Seawater – Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Dietz, Travis Cameron [Univ. of Maryland, College Park, MD (United States); Tsinas, Zois [Univ. of Maryland, College Park, MD (United States); Tomaszewski, Claire [Univ. of Maryland, College Park, MD (United States); Pazos, Ileana [Univ. of Maryland, College Park, MD (United States); Nigliazzo, Olga [University of Palermo, Palermo (Italy); Li, Weixing [Univ. of Maryland, College Park, MD (United States); Adel-Hadadi, Mohammad [Univ. of Maryland, College Park, MD (United States); Barkatt, Aaron [The Catholic Univ. of America, Washington, DC (United States); Al-Sheikhly, Mohamad [Univ. of Maryland, College Park, MD (United States)

    2016-05-16

    Even at a concentration of 3 μg/L, the world’s oceans contain a thousand times more uranium than currently know terrestrial sources. In order to take advantage of this stockpile, methods and materials must be developed to extract it efficiently, a difficult task considering the very low concentration of the element and the competition for extraction by other atoms in seawater such as sodium, calcium, and vanadium. The majority of current research on methods to extract uranium from seawater are vertical explorations of the grafting of amidoxime ligand, which was originally discovered and promoted by Japanese studies in the late 1980s. Our study expands on this research horizontally by exploring the effectiveness of novel uranium extraction ligands grafted to the surface of polymer substrates using radiation. Through this expansion, a greater understanding of uranium binding chemistry and radiation grafting effects on polymers has been obtained. While amidoxime-functionalized fabrics have been shown to have the greatest extraction efficiency so far, they suffer from an extensive chemical processing step which involves treatment with powerful basic solutions. Not only does this add to the chemical waste produced in the extraction process and add to the method’s complexity, but it also significantly impacts the regenerability of the amidoxime fabric. The approach of this project has been to utilize alternative, commercially available monomers capable of extracting uranium and containing a carbon-carbon double bond to allow it to be grafted using radiation, specifically phosphate, oxalate, and azo monomers. The use of commercially available monomers and radiation grafting with electron beam or gamma irradiation will allow for an easily scalable fabrication process once the technology has been optimized. The need to develop a cheap and reliable method for extracting uranium from seawater is extremely valuable to energy independence, and will extend the quantity of

  17. Monitoring and modeling infiltration-recharge dynamics of managed aquifer recharge with desalinated seawater

    OpenAIRE

    Ganot, Yonatan; Holtzman, Ran; Weisbrod, Noam; Nitzan, Ido; Katz, Yoram; Kurtzman, Daniel

    2016-01-01

    We study the relation between surface infiltration and groundwater recharge during managed aquifer recharge (MAR) with desalinated seawater in an infiltration pond, at the Menashe site that overlies the northern part of the Israeli Coastal Aquifer. We monitor infiltration dynamics at multiple scales (up to the scale of the entire pond) by measuring the ponding depth, sediment water content and groundwater levels, using pressure sensors, single-ring infiltrometers, soil sensors and observation...

  18. A normalised seawater strontium isotope curve. Possible implications for Neoproterozoic-Cambrian weathering rates and the further oxygenation of the Earth

    International Nuclear Information System (INIS)

    Shields, G.A.

    2007-01-01

    The strontium isotope composition of seawater is strongly influenced on geological time scales by changes in the rates of continental weathering relative to ocean crust alteration. However, the potential of the seawater 87 Sr/ 86 Sr curve to trace globally integrated chemical weathering rates has not been fully realised because ocean 87 Sr/ 86 Sr is also influenced by the isotopic evolution of Sr sources to the ocean. A preliminary attempt is made here to normalise the seawater 87 Sr/ 86 Sr curve to plausible trends in the 87 Sr/ 86 Sr ratios of the three major Sr sources: carbonate dissolution, silicate weathering and submarine hydrothermal exchange. The normalised curve highlights the Neoproterozoic-Phanerozoic transition as a period of exceptionally high continental influence, indicating that this interval was characterised by a transient increase in global weathering rates and/or by the weathering of unusually radiogenic crustal rocks. Close correlation between the normalised 87 Sr/ 86 Sr curve, a published seawater δ 34 S curve and atmospheric pCO 2 models is used here to argue that elevated chemical weathering rates were a major contributing factor to the steep rise in seawater 87 Sr/ 86 Sr from 650 Ma to 500 Ma. Elevated weathering rates during the Neoproterozoic-Cambrian interval led to increased nutrient availability, organic burial and to the further oxygenation of Earth's surface environment. Use of normalised seawater 87 Sr/ 86 Sr curves will, it is hoped, help to improve future geochemical models of Earth System dynamics. (orig.)

  19. Cathodic properties of different stainless steels in natural seawater

    International Nuclear Information System (INIS)

    Johnsen, R.; Bardal, E.

    1985-01-01

    The cathodic properties of a number of stainless steels, which were exposed to natural seawater flowing at 0 to 2.5 m/s and polarized to potentials from -300 to -950 mV SCE, have been studied. The current density development at constant potential and the free corrosion potential during the exposure time were recorded continuously. At the end of the exposure period, after approximately 28 to 36 days of exposure, polarization curves were determined. After one to three weeks of exposure, depending on the water velocity, microbiological activity on the surface caused an increase in the current density requirement of the specimen. An explanation for the mechanism behind the current density increase caused by slime production from marine bacteria may be increased exchange current density, i 0 . There was no measurable calcareous deposit on the stainless steel surfaces at the end of the exposure periods

  20. Biodegradation of phenanthrene in artificial seawater by using free ...

    African Journals Online (AJOL)

    and related aromatic compounds. This paper reports the domestication of strain Sphingomonas sp. GY2B in artificial seawater (AS) and the immobilization of the strain onto rice straw. Results showed that adding 85% artificial seawater had very low impact on the growth and phenanthrene degradation ability of strain GY2B ...

  1. Substrate Use of Pseudovibrio sp. Growing in Ultra-Oligotrophic Seawater

    Science.gov (United States)

    Schwedt, Anne; Seidel, Michael; Dittmar, Thorsten; Simon, Meinhard; Bondarev, Vladimir; Romano, Stefano; Lavik, Gaute; Schulz-Vogt, Heide N.

    2015-01-01

    Marine planktonic bacteria often live in habitats with extremely low concentrations of dissolved organic matter (DOM). To study the use of trace amounts of DOM by the facultatively oligotrophic Pseudovibrio sp. FO-BEG1, we investigated the composition of artificial and natural seawater before and after growth. We determined the concentrations of dissolved organic carbon (DOC), total dissolved nitrogen (TDN), free and hydrolysable amino acids, and the molecular composition of DOM by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR-MS). The DOC concentration of the artificial seawater we used for cultivation was 4.4 μmol C L-1, which was eight times lower compared to the natural oligotrophic seawater we used for parallel experiments (36 μmol C L -1). During the three-week duration of the experiment, cell numbers increased from 40 cells mL-1 to 2x104 cells mL -1 in artificial and to 3x105 cells mL -1 in natural seawater. No nitrogen fixation and minor CO2 fixation (seawater, using unexpected organic compounds to fuel their energy, carbon and nitrogen requirements. PMID:25826215

  2. Antibacterial activity of marine culturable bacteria collected from a global sampling of ocean surface waters and surface swabs of marine organisms

    DEFF Research Database (Denmark)

    Gram, Lone; Melchiorsen, Jette; Bruhn, Jesper Bartholin

    2010-01-01

    ). Total cell counts at the seawater surface were 5 × 105 to 106 cells/ml, of which 0.1–0.2% were culturable on dilute marine agar (20°C). Three percent of the colonies cultured from seawater inhibited Vibrio anguillarum, whereas a significantly higher proportion (13%) of colonies from inert or biotic...

  3. Zircon (U-Th)/He Thermochronometric Constraints on Himalayan Thrust Belt Exhumation, Bedrock Weathering, and Cenozoic Seawater Chemistry

    Science.gov (United States)

    Colleps, Cody L.; McKenzie, N. Ryan; Stockli, Daniel F.; Hughes, Nigel C.; Singh, Birendra P.; Webb, A. Alexander G.; Myrow, Paul M.; Planavsky, Noah J.; Horton, Brian K.

    2018-01-01

    Shifts in global seawater 187Os/188Os and 87Sr/86Sr are often utilized as proxies to track global weathering processes responsible for CO2 fluctuations in Earth history, particularly climatic cooling during the Cenozoic. It has been proposed, however, that these isotopic records instead reflect the weathering of chemically distinctive Himalayan lithologies exposed at the surface. We present new zircon (U-Th)/He thermochronometric and detrital zircon U-Pb geochronologic evidence from the Himalaya of northwest India to explore these contrasting interpretations concerning the driving mechanisms responsible for these seawater records. Our data demonstrate in-sequence southward thrust propagation with rapid exhumation of Lesser Himalayan strata enriched in labile 187Os and relatively less in radiogenic 87Sr at ˜16 Ma, which directly corresponds with coeval shifts in seawater 187Os/188Os and 87Sr/86Sr. Results presented here provide substantial evidence that the onset of exhumation of 187Os-enriched Lesser Himalayan strata could have significantly impacted the marine 187Os/188Os record at 16 Ma. These results support the hypothesis that regional weathering of isotopically unique source rocks can drive seawater records independently from shifts in global-scale weathering rates, hindering the utility of these records as reliable proxies to track global weathering processes and climate in deep geologic time.

  4. Surface reconstruction processes in MO VPE grown GaAs layers

    Czech Academy of Sciences Publication Activity Database

    Nohavica, Dušan

    1999-01-01

    Roč. 50, 2/s (1999), s. 24-25 ISSN 1335-3632. [Development of Materials Science in Research and Education - DMS -RE 1998 /8./. Zlenice, 08.09.1998-10.09.1998] R&D Projects: GA AV ČR IAA2067901 Institutional research plan: CEZ:AV0Z2067918 Keywords : epitaxial growth * surface reconstruction Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  5. Room temperature d (0) ferromagnetism in hole doped Y2O3: widening the choice of host to tailor DMS.

    Science.gov (United States)

    Chakraborty, Brahmananda; Ramaniah, Lavanya M

    2016-08-24

    Transition metal-free-ferromagnetism in diluted magnetic semiconductors (DMS) is of much current interest in view of the search for more efficient DMS materials for spintronics applications. Our DFT results predict for the first time, that impurities from group1A (Li(+), Na(+), K(+)) doped on Y2O3 can induce a magnetic signature with a magnetic moment around 2.0 μ B per defect at hole concentrations around 1.63  ×  10(21) cm(-3), which is one order less than the critical hole density of ZnO with ferromagnetic coupling large enough to promote room temperature ferromagnetism. The induction of room temperature ferromagnetism by hole doping with an impurity atom from group 1A, which injects two holes per defect in the system, implies that the recommendation of three holes per defect given in the literature, which puts a restriction on the choice of host material and the impurity, is not a necessary criterion for hole induced room temperature ferromagnetism. DFT simulations with the generalized gradient approximation (GGA), confirmed by the more sophisticated hybrid functional, Heyd-Scuseria-Ernzerhof (HSE06), predict that the magnetic moment is mostly contributed by O atoms surrounding the impurity atom and the magnetic moment scale up with impurity concentration which is a positive indicator for practical applications. We quantitatively and extensively demonstrate through the analysis of the density of states and ferromagnetic coupling that the Stoner criterion is satisfied by pushing the Fermi level inside the valence band to activate room temperature ferromagnetism. The stability of the structure and the persistence of ferromagnetism at room temperature were demonstrated by ab initio MD simulations and computation of Curie temperature through the mean field approximation. This study widens the choice of host oxides to tailor DMS for spintronics applications.

  6. Impediment to Symbiosis Establishment between Giant Clams and Symbiodinium Algae Due to Sterilization of Seawater

    Science.gov (United States)

    Kurihara, Takeo; Yamada, Hideaki; Inoue, Ken; Iwai, Kenji; Hatta, Masayuki

    2013-01-01

    To survive the juvenile stage, giant clam juveniles need to establish a symbiotic relationship with the microalgae Symbiodinium occurring in the environment. The percentage of giant clam juveniles succeeding in symbiosis establishment (“symbiosis rate”) is often low, which is problematic for seed producers. We investigated how and why symbiosis rates vary, depending on whether giant clam seeds are continuously reared in UV treated or non treated seawater. Results repeatedly demonstrated that symbiosis rates were lower for UV treated seawater than for non treated seawater. Symbiosis rates were also lower for autoclaved seawater and 0.2-µm filtered seawater than for non treated seawater. The decreased symbiosis rates in various sterilized seawater suggest the possibility that some factors helping symbiosis establishment in natural seawater are weakened owing to sterilization. The possible factors include vitality of giant clam seeds, since additional experiments revealed that survival rates of seeds reared alone without Symbiodinium were lower in sterilized seawater than in non treated seawater. In conclusion, UV treatment of seawater was found to lead to decreased symbiosis rates, which is due possibly to some adverse effects common to the various sterilization techniques and relates to the vitality of the giant clam seeds. PMID:23613802

  7. The density-salinity relation of standard seawater

    Science.gov (United States)

    Schmidt, Hannes; Seitz, Steffen; Hassel, Egon; Wolf, Henning

    2018-01-01

    The determination of salinity by means of electrical conductivity relies on stable salt proportions in the North Atlantic Ocean, because standard seawater, which is required for salinometer calibration, is produced from water of the North Atlantic. To verify the long-term stability of the standard seawater composition, it was proposed to perform measurements of the standard seawater density. Since the density is sensitive to all salt components, a density measurement can detect any change in the composition. A conversion of the density values to salinity can be performed by means of a density-salinity relation. To use such a relation with a target uncertainty in salinity comparable to that in salinity obtained from conductivity measurements, a density measurement with an uncertainty of 2 g m-3 is mandatory. We present a new density-salinity relation based on such accurate density measurements. The substitution measurement method used is described and density corrections for uniform isotopic and chemical compositions are reported. The comparison of densities calculated using the new relation with those calculated using the present reference equations of state TEOS-10 suggests that the density accuracy of TEOS-10 (as well as that of EOS-80) has been overestimated, as the accuracy of some of its underlying density measurements had been overestimated. The new density-salinity relation may be used to verify the stable composition of standard seawater by means of routine density measurements.

  8. Sea-to-air flux of dimethyl sulfide in the South and North Pacific Ocean as measured by proton transfer reaction-mass spectrometry coupled with the gradient flux technique

    Science.gov (United States)

    Omori, Yuko; Tanimoto, Hiroshi; Inomata, Satoshi; Ikeda, Kohei; Iwata, Toru; Kameyama, Sohiko; Uematsu, Mitsuo; Gamo, Toshitaka; Ogawa, Hiroshi; Furuya, Ken

    2017-07-01

    Exchange of dimethyl sulfide (DMS) between the surface ocean and the lower atmosphere was examined by using proton transfer reaction-mass spectrometry coupled with the gradient flux (PTR-MS/GF) system. We deployed the PTR-MS/GF system and observed vertical gradients of atmospheric DMS just above the sea surface in the subtropical and transitional South Pacific Ocean and the subarctic North Pacific Ocean. In total, we obtained 370 in situ profiles, and of these we used 46 data sets to calculate the sea-to-air flux of DMS. The DMS flux determined was in the range from 1.9 to 31 μmol m-2 d-1 and increased with wind speed and biological activity, in reasonable accordance with previous observations in the open ocean. The gas transfer velocity of DMS derived from the PTR-MS/GF measurements was similar to either that of DMS determined by the eddy covariance technique or that of insoluble gases derived from the dual tracer experiments, depending on the observation sites located in different geographic regions. When atmospheric conditions were strongly stable during the daytime in the subtropical ocean, the PTR-MS/GF observations captured a daytime versus nighttime difference in DMS mixing ratios in the surface air overlying the ocean surface. The difference was mainly due to the sea-to-air DMS emissions and stable atmospheric conditions, thus affecting the gradient of DMS. This indicates that the DMS gradient is strongly controlled by diurnal variations in the vertical structure of the lower atmosphere above the ocean surface.

  9. Methane-oxidizing seawater microbial communities from an Arctic shelf

    Science.gov (United States)

    Uhlig, Christiane; Kirkpatrick, John B.; D'Hondt, Steven; Loose, Brice

    2018-06-01

    Marine microbial communities can consume dissolved methane before it can escape to the atmosphere and contribute to global warming. Seawater over the shallow Arctic shelf is characterized by excess methane compared to atmospheric equilibrium. This methane originates in sediment, permafrost, and hydrate. Particularly high concentrations are found beneath sea ice. We studied the structure and methane oxidation potential of the microbial communities from seawater collected close to Utqiagvik, Alaska, in April 2016. The in situ methane concentrations were 16.3 ± 7.2 nmol L-1, approximately 4.8 times oversaturated relative to atmospheric equilibrium. The group of methane-oxidizing bacteria (MOB) in the natural seawater and incubated seawater was > 97 % dominated by Methylococcales (γ-Proteobacteria). Incubations of seawater under a range of methane concentrations led to loss of diversity in the bacterial community. The abundance of MOB was low with maximal fractions of 2.5 % at 200 times elevated methane concentration, while sequence reads of non-MOB methylotrophs were 4 times more abundant than MOB in most incubations. The abundances of MOB as well as non-MOB methylotroph sequences correlated tightly with the rate constant (kox) for methane oxidation, indicating that non-MOB methylotrophs might be coupled to MOB and involved in community methane oxidation. In sea ice, where methane concentrations of 82 ± 35.8 nmol kg-1 were found, Methylobacterium (α-Proteobacteria) was the dominant MOB with a relative abundance of 80 %. Total MOB abundances were very low in sea ice, with maximal fractions found at the ice-snow interface (0.1 %), while non-MOB methylotrophs were present in abundances similar to natural seawater communities. The dissimilarities in MOB taxa, methane concentrations, and stable isotope ratios between the sea ice and water column point toward different methane dynamics in the two environments.

  10. Properties and Fluxes of Primary Marine Aerosol Generated Via Detrainment of Turbulence-Modulated Bubble Plumes from Fresh North Atlantic Seawater

    Science.gov (United States)

    Keene, W. C.; Long, M. S.; Duplessis, P.; Kieber, D. J.; Maben, J. R.; Frossard, A. A.; Kinsey, J. D.; Beaupre, S. R.; Lu, X.; Chang, R.; Zhu, Y.; Bisgrove, J.

    2017-12-01

    During a September-October 2016 cruise of the R/V Endeavor in the western North Atlantic Ocean, primary marine aerosol (PMA) was produced in a high capacity generator during day and night via detrainment of bubbles from biologically productive and oligotrophic seawater. The turbulent mixing of clean air and seawater in a Venturi nozzle produced bubble plumes with tunable size distributions. Physicochemical characteristics of size-resolved PMA and seawater were measured. PMA number production efficiencies per unit air detrained (PEnum) increased with increasing detainment rate. For given conditions, PEnum values summed over size distributions were roughly ten times greater than those for frits whereas normalized size distributions were similar. Results show that bubble size distributions significantly modulated number production fluxes but not relative shapes of corresponding size distributions. In contrast, mass production efficiencies (PEmass) decreased with increasing air detrainment and were similar to those for frits, consistent with the hypothesis that bubble rafts on the seawater surface modulate emissions of larger jet droplets that dominate PMA mass production. Production efficiencies of organic matter were about three times greater than those for frits whereas organic enrichment factors integrated over size distributions were similar.

  11. Physiological, molecular, and cellular mechanisms of impaired seawater tolerance following exposure of Atlantic salmon, Salmo salar, smolts to acid and aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Monette, Michelle Y., E-mail: michelle.monette@yale.edu [Organismic and Evolutionary Biology Program, University of Massachusetts, Amherst, MA 01003 (United States); USGS, Conte Anadromous Fish Research Center, Turners Falls, MA 01376 (United States); Yada, Takashi [Freshwater Fisheries Research Department, National Research Institute of Fisheries Science, Nikko (Japan); Matey, Victoria [Department of Biology, San Diego State University, San Diego, CA 92182 (United States); McCormick, Stephen D. [Organismic and Evolutionary Biology Program, University of Massachusetts, Amherst, MA 01003 (United States); USGS, Conte Anadromous Fish Research Center, Turners Falls, MA 01376 (United States)

    2010-08-01

    We examined the physiological, molecular, and cellular mechanisms of impaired ion regulation in Atlantic salmon, Salmo salar, smolts following acute acid and aluminum (Al) exposure. Smolts were exposed to: control (pH 6.5, 3.4 {mu}g l{sup -1} Al), acid and low Al (LAl: pH 5.4, 11 {mu}g l{sup -1} Al), acid and moderate Al (MAl: pH 5.3, 42 {mu}g l{sup -1} Al), and acid and high Al (HAl: pH 5.4, 56 {mu}g l{sup -1} Al) for two and six days. At each time-point, smolts were sampled directly from freshwater treatment tanks and after a 24 h seawater challenge. Exposure to acid/MAl and acid/HAl led to accumulation of gill Al, substantial alterations in gill morphology, reduced gill Na{sup +}/K{sup +}-ATPase (NKA) activity, and impaired ion regulation in both freshwater and seawater. Exposure to acid/MAl for six days also led to a decrease in gill mRNA expression of the apical Cl{sup -} channel (cystic fibrosis transmembrane conductance regulator I), increased apoptosis upon seawater exposure, an increase in the surface expression of mitochondria-rich cells (MRCs) within the filament epithelium of the gill, but reduced abundance of gill NKA-positive MRCs. By contrast, smolts exposed to acid and the lowest Al concentration exhibited minor gill Al accumulation, slight morphological modifications in the gill, and impaired seawater tolerance in the absence of a detectable effect on freshwater ion regulation. These impacts were accompanied by decreased cell proliferation, a slight increase in the surface expression of MRCs within the filament epithelium, but no impact on gill apoptosis or total MRC abundance was observed. However, MRCs in the gills of smolts exposed to acid/LAl exhibited morphological alterations including decreased size, staining intensity, and shape factor. We demonstrate that the seawater tolerance of Atlantic salmon smolts is extremely sensitive to acute exposure to acid and low levels of Al, and that the mechanisms underlying this depend on the time

  12. Physiological, molecular, and cellular mechanisms of impaired seawater tolerance following exposure of Atlantic salmon, Salmo salar, smolts to acid and aluminum

    International Nuclear Information System (INIS)

    Monette, Michelle Y.; Yada, Takashi; Matey, Victoria; McCormick, Stephen D.

    2010-01-01

    We examined the physiological, molecular, and cellular mechanisms of impaired ion regulation in Atlantic salmon, Salmo salar, smolts following acute acid and aluminum (Al) exposure. Smolts were exposed to: control (pH 6.5, 3.4 μg l -1 Al), acid and low Al (LAl: pH 5.4, 11 μg l -1 Al), acid and moderate Al (MAl: pH 5.3, 42 μg l -1 Al), and acid and high Al (HAl: pH 5.4, 56 μg l -1 Al) for two and six days. At each time-point, smolts were sampled directly from freshwater treatment tanks and after a 24 h seawater challenge. Exposure to acid/MAl and acid/HAl led to accumulation of gill Al, substantial alterations in gill morphology, reduced gill Na + /K + -ATPase (NKA) activity, and impaired ion regulation in both freshwater and seawater. Exposure to acid/MAl for six days also led to a decrease in gill mRNA expression of the apical Cl - channel (cystic fibrosis transmembrane conductance regulator I), increased apoptosis upon seawater exposure, an increase in the surface expression of mitochondria-rich cells (MRCs) within the filament epithelium of the gill, but reduced abundance of gill NKA-positive MRCs. By contrast, smolts exposed to acid and the lowest Al concentration exhibited minor gill Al accumulation, slight morphological modifications in the gill, and impaired seawater tolerance in the absence of a detectable effect on freshwater ion regulation. These impacts were accompanied by decreased cell proliferation, a slight increase in the surface expression of MRCs within the filament epithelium, but no impact on gill apoptosis or total MRC abundance was observed. However, MRCs in the gills of smolts exposed to acid/LAl exhibited morphological alterations including decreased size, staining intensity, and shape factor. We demonstrate that the seawater tolerance of Atlantic salmon smolts is extremely sensitive to acute exposure to acid and low levels of Al, and that the mechanisms underlying this depend on the time-course and severity of Al exposure. We propose

  13. Physiological, molecular, and cellular mechanisms of impaired seawater tolerance following exposure of Atlantic salmon, Salmo salar, smolts to acid and aluminum

    Science.gov (United States)

    Monette, M.Y.; Yada, T.; Matey, V.; McCormick, S.D.

    2010-01-01

    We examined the physiological, molecular, and cellular mechanisms of impaired ion regulation in Atlantic salmon, Salmo salar, smolts following acute acid and aluminum (Al) exposure. Smolts were exposed to: control (pH 6.5, 3.4??gl-1 Al), acid and low Al (LAl: pH 5.4, 11??gl-1 Al), acid and moderate Al (MAl: pH 5.3, 42??gl-1 Al), and acid and high Al (HAl: pH 5.4, 56??gl-1 Al) for two and six days. At each time-point, smolts were sampled directly from freshwater treatment tanks and after a 24h seawater challenge. Exposure to acid/MAl and acid/HAl led to accumulation of gill Al, substantial alterations in gill morphology, reduced gill Na+/K+-ATPase (NKA) activity, and impaired ion regulation in both freshwater and seawater. Exposure to acid/MAl for six days also led to a decrease in gill mRNA expression of the apical Cl- channel (cystic fibrosis transmembrane conductance regulator I), increased apoptosis upon seawater exposure, an increase in the surface expression of mitochondria-rich cells (MRCs) within the filament epithelium of the gill, but reduced abundance of gill NKA-positive MRCs. By contrast, smolts exposed to acid and the lowest Al concentration exhibited minor gill Al accumulation, slight morphological modifications in the gill, and impaired seawater tolerance in the absence of a detectable effect on freshwater ion regulation. These impacts were accompanied by decreased cell proliferation, a slight increase in the surface expression of MRCs within the filament epithelium, but no impact on gill apoptosis or total MRC abundance was observed. However, MRCs in the gills of smolts exposed to acid/LAl exhibited morphological alterations including decreased size, staining intensity, and shape factor. We demonstrate that the seawater tolerance of Atlantic salmon smolts is extremely sensitive to acute exposure to acid and low levels of Al, and that the mechanisms underlying this depend on the time-course and severity of Al exposure. We propose that when smolts are

  14. Freeze desalination of seawater using LNG cold energy

    KAUST Repository

    Chang, Jian; Zuo, Jian; Lu, Kang-Jia; Chung, Neal Tai-Shung

    2016-01-01

    With the aid of cold energy from regasification of liquefied natural gas (LNG), freeze desalination (FD) is an emerging technology for seawater desalination because of its low energy characteristics and insensitivities to fouling problems. This work aims to investigate the major operating parameters of FD such as coolant temperature, freezing duration, supercooling, seeding, agitation, crystallizer material and subsequent washing procedure on ice production and water quality. It was found that the optimal freezing duration per batch was 1 h for an iron crystallizer and 1.5 h for a glass crystallizer. The optimal coolant temperature should be around −8 °C. The optimal amount of washing water to clean the raw ice was about 50 wt% of the raw ice. Over 50 wt% of the feed could be recovered as raw ice within 1 h, which means an overall ice recovery rate of higher than 25% (of the original seawater), considering the consumption of washing water. Both artificial and real seawater were tested under the optimized conditions. The total dissolved solid in the product ice was around 300 ppm, which met the World Health Organization (WHO) potable water salinity standard of 500 ppm. Therefore, the process parameters optimized in this study can be directly used for the freeze desalination of seawater.

  15. Freeze desalination of seawater using LNG cold energy

    KAUST Repository

    Chang, Jian

    2016-06-23

    With the aid of cold energy from regasification of liquefied natural gas (LNG), freeze desalination (FD) is an emerging technology for seawater desalination because of its low energy characteristics and insensitivities to fouling problems. This work aims to investigate the major operating parameters of FD such as coolant temperature, freezing duration, supercooling, seeding, agitation, crystallizer material and subsequent washing procedure on ice production and water quality. It was found that the optimal freezing duration per batch was 1 h for an iron crystallizer and 1.5 h for a glass crystallizer. The optimal coolant temperature should be around −8 °C. The optimal amount of washing water to clean the raw ice was about 50 wt% of the raw ice. Over 50 wt% of the feed could be recovered as raw ice within 1 h, which means an overall ice recovery rate of higher than 25% (of the original seawater), considering the consumption of washing water. Both artificial and real seawater were tested under the optimized conditions. The total dissolved solid in the product ice was around 300 ppm, which met the World Health Organization (WHO) potable water salinity standard of 500 ppm. Therefore, the process parameters optimized in this study can be directly used for the freeze desalination of seawater.

  16. Extraction of Carbon Dioxide and Hydrogen from Seawater and Hydrocarbon Production Therefrom

    Science.gov (United States)

    2016-04-05

    acidification of seawater by subjecting the seawater to an ion exchange reaction to exchange H.sup. ions for Na.sup. ions. Carbon dioxide may be...extracted from the acidified seawater. Optionally, the ion exchange reaction can be conducted under conditions which produce hydrogen as well as carbon dioxide . The carbon dioxide and hydrogen may be used to produce hydrocarbons.

  17. Modelling of a transmembrane evaporation module for desalination of seawater

    NARCIS (Netherlands)

    Guijt, C.M.; Racz, I.G.; van Heuven, Jan Willem; Reith, T.; de Haan, A.B.

    1999-01-01

    Transmembrane evaporation (often called membrane distillation) carried out in a countercurrent flow module, in which incoming cold seawater is heated by the condensing product water flow, is a promising technology for low-cost seawater desalination. This paper presents a model for preliminary design

  18. Recovery of uranium from sea-water

    International Nuclear Information System (INIS)

    Llewelyn, G.I.W.

    1976-01-01

    The possibility of extraction of uranium from sea-water on a sufficiently large scale to contribute significantly to national UK requirements is placed in perspective. It seems unlikely that there are sites around the UK coast where this could be achieved, and insufficient work has been done to be confident that sites exist anywhere to enable uranium extraction to be carried out on a large scale. Process techniques have been developed on a small scale, but extensive further research work would be necessary to reduce appreciably the present uncertainties. It would be unwise to expect uranium from sea-water to contribute significant amounts to the world's uranium demand for thermal reactors on an acceptable timescale. (author)

  19. Effect of Groundwater Pumping on Seawater Intrusion in Coastal Aquifers

    Directory of Open Access Journals (Sweden)

    M.M. Sherif

    2002-06-01

    Full Text Available Many aquifers around the globe are located in coastal areas and are thus subjected to the seawater intrusion phenomenon. The growth of population in coastal areas and the conjugate increase in human, agricultural, and industrial activities have imposed an increasing demand for freshwater. This increase in water demand is often covered by extensive pumping of fresh groundwater, causing subsequent lowering of the water table (or piezometric head and upsetting the dynamic balance between freshwater and saline water bodies. The classical result of such a development is seawater intrusion. This paper presents a review for the seawater intrusion phenomenon in coastal aquifers. The effect of pumping activities on the seawater intrusion in the Nile Delta aquifer of Egypt is investigated. It was concluded that any additional pumping should be located in the middle Delta and avoided in the eastern and western sides of the Delta.

  20. Experimental seawater-basaltic glass interaction at 50°C: Study of early developed phases by electron microscopy and X-ray photoelectron spectrometry

    Science.gov (United States)

    Crovisier, J. L.; Thomassin, J. H.; Juteau, T.; Eberhart, J. P.; Touray, J. C.; Baillif, P.

    1983-03-01

    Experiments on seawater-basaltic glass interaction were made using a particulary high seawater-basaltic glass ratio (14.5 g/cm 2; weight ratio: 50). A layered alteration skin is observed at the glass surface, while the variations in the composition of the seawater are imperceptible. Three zones of different composition and structure are distinguished: 1) An external zone, the composition of which evolved to saponite. 2) A median zone of hydrotalcite-like hydroxycarbonate (Mg 6Al 2CO 3(OH) 164H 2O). 3) An internal zone, between glass and hydroxycarbonates, richer in Fe and in Mg and in which a 10 Å interval is observed (by dark field examination) compatible with a TOT type clay mineral. The composition of this zone indicates a mixing of poorly crystalline products. The principal chemical exchanges between glass and solution are the release of Ca in solution and the contribution of Mg and CO 2 from seawater to form hydroxycarbonates, which are considered precursors of phyllosilicates. Comparison with natural phenomena (palagonitization) is made.

  1. Energy Implications of Seawater Desalination (Invited)

    Science.gov (United States)

    Cooley, H.; Heberger, M. G.

    2013-12-01

    Freshwater has traditionally come from rivers, lakes, streams, and groundwater aquifers. As demand increases and climate change alters the location and timing of water supply, these traditional sources are becoming unavailable, more difficult, or increasingly expensive to develop. As a result, many communities are switching to alternative sources of water. Interest in pursuing seawater desalination is high in many coastal communities. In California, for example, 17 plants are proposed for development along the California coast and two in Mexico. Water managers are pursing desalination because is a local supply that can help diversify the water supply portfolio. Additionally, it is a reliable supply, which can be especially valuable during a drought. But removing the salt from seawater is an energy-intensive process that consumes more energy per gallon than most other water supply and treatment options. These energy requirements are key factors that will impact the extent and success of desalination in California. Energy requirements for seawater desalination average about 4.0 kWh per cubic meter (m3) of water produced. By comparison, the least energy-intensive options of local sources of groundwater and surface water require 0 - 0.90 kWh per m3; wastewater reuse, depending on treatment levels, may require from 0.26 - 2.2 kWh per m3. Beyond the electricity required for the desalination facility itself, producing any new source of water, including through desalination, increases the amount of energy required to deliver and use the water produced as well as collect, treat, and dispose of the wastewater generated. Energy is the largest single variable cost for a desalination plant, varying from one-third to more than one-half the cost of produced water. Building a desalination plant may reduce a water utility's exposure to water reliability risks at the added expense of an increase in exposure to energy price risk. In dependent on hydropower, electricity prices tend to

  2. Seawater calcium isotope ratios across the Eocene-Oligocene transition

    Science.gov (United States)

    Griffith, E.M.; Paytan, A.; Eisenhauer, A.; Bullen, T.D.; Thomas, E.

    2011-01-01

    During the Eocene-Oligocene transition (EOT, ca. 34 Ma), Earth's climate cooled significantly from a greenhouse to an icehouse climate, while the calcite (CaCO3) compensation depth (CCD) in the Pacific Ocean increased rapidly. Fluctuations in the CCD could result from various processes that create an imbalance between calcium (Ca) sources to, and sinks from, the ocean (e.g., weathering and CaCO3 deposition), with different effects on the isotopic composition of dissolved Ca in the oceans due to differences in the Ca isotopic composition of various inputs and outputs. We used Ca isotope ratios (??44/40Ca) of coeval pelagic marine barite and bulk carbonate to evaluate changes in the marine Ca cycle across the EOT. We show that the permanent deepening of the CCD was not accompanied by a pronounced change in seawater ??44/40Ca, whereas time intervals in the Neogene with smaller carbonate depositional changes are characterized by seawater ??44/40Ca shifts. This suggests that the response of seawater ??44/40Ca to changes in weathering fluxes and to imbalances in the oceanic alkalinity budget depends on the chemical composition of seawater. A minor and transient fluctuation in the Ca isotope ratio of bulk carbonate may reflect a change in isotopic fractionation associated with CaCO3 precipitation from seawater due to a combination of factors, including changes in temperature and/or in the assemblages of calcifying organisms. ?? 2011 Geological Society of America.

  3. Corrosion in seawater systems

    International Nuclear Information System (INIS)

    Henrikson, S.

    1988-01-01

    Highly alloyed stainless steels have been exposed to natural chlorinated and chlorine-free seawater at 35 deg. C. Simulated tube-tubesheet joints, weld joints and galvanic couples with titanium, 90/10 CuNi and NiAl bronze were tested and evaluated for corrosion. The corrosion rates of various anode materials - zinc, aluminium and soft iron - were also determined. Finally the risk of hydrogen embrittlement of tubes of ferritic stainless steels and titanium as a consequence of cathodic protection was studied. An attempt was also made to explain the cracking mechanism of the ferritic steels by means of transmission electron microscopy. One important conclusion of the project is that chlorinated seawater is considerably more corrosive to stainless steels than chlorine-free water, whereas chlorination reduces the rate of galvanic corrosion of copper materials coupled to stainless steels. Hydrogen embrittlement of ferritic stainless steels and titanium as a consequence of cathodic protection of carbon steel or cast iron in the same structure can be avoided by strict potentiostatic control of the applied potential. (author)

  4. Development of a process for continuous extraction of uranium from seawater

    International Nuclear Information System (INIS)

    Yun, C.K.

    1982-03-01

    Hydrous titanium oxide, titanium phosphate, galena (PbS), polystyrene beads containing TBP were preliminarily tested, using artificial seawater. Galena indicated the capacity of 1.1mg U/g PbS and faster reaction rates, whereas, hydrous titanium oxide showed 0.6mg U/g Ti and slow rates. The adsorption performance of galena was not changed after repeated use and regeneration with dil. HCl solutions. The effective surface of galena beads was 0.4mm in depth. Elution of uranium form adsorbents was examined by both acid and alkali methods; the latter showed preferred condition. Secondary concentration of uranium by Amberlite IRA-400 was also studies. Eventually, two types of packed systems with galena (columns and panels) were installed in the seawater channel of a thermal power plant. The maximum adsorption of 150μg U/g PbS was obtained using the packed column. Based on the experimental data, the authors made a conceptual design for a test plant of the production capacity 12Kg U 3 O 8 /y. The construction would cost about $1 million and the operation cost is estimated at $115.20/lb U 3 O 8

  5. Plasmonic heating from indium nanoparticles on a floating microporous membrane for enhanced solar seawater desalination.

    Science.gov (United States)

    Zhang, Lulu; Xing, Jun; Wen, Xinglin; Chai, Jianwei; Wang, Shijie; Xiong, Qihua

    2017-09-14

    Passive solar evaporation represents a promising and environmentally benign method of water purification/desalination. Plasmonic nanoparticles have been demonstrated as an effective approach for enhancing solar steam generation through a plasmonic heating effect, nonetheless the efficiency is constrained by unnecessary bulk heating of the entire liquid volume, while the noble metals commonly used are not cost-effective in terms of availability and their sophisticated preparation. Herein, a paper-like plasmonic device consisting of a microporous membrane and indium nanoparticles (In NPs/MPM) is fabricated through a simple thermal evaporation method. Due to the light-weight and porous nature of the device, the broadband light absorption properties, and theoretically the excellent plasmonic heating effect from In NP which could be even higher than gold, silver and aluminium nanoparticles, our device can effectively enhance solar water evaporation by floating on the water surface and its utility has been demonstrated in the solar desalination of a real seawater sample. The durability of the device in solar seawater desalination has also been investigated over multiple cycles with stable performances. This portable device could provide a solution for individuals to do water/seawater purification in under-developed areas with limited/no access to electricity or a centralized drinking water supply.

  6. Rare earth element geochemistry characteristics of seawater and porewater from deep sea in western Pacific.

    Science.gov (United States)

    Deng, Yinan; Ren, Jiangbo; Guo, Qingjun; Cao, Jun; Wang, Haifeng; Liu, Chenhui

    2017-11-28

    Deep-sea sediments contain high concentrations of rare earth element (REE) which have been regarded as a huge potential resource. Understanding the marine REE cycle is important to reveal the mechanism of REE enrichment. In order to determine the geochemistry characteristics and migration processes of REE, seawater, porewater and sediment samples were systematically collected from the western Pacific for REE analysis. The results show a relatively flat REE pattern and the HREE (Heavy REE) enrichment in surface and deep seawater respectively. The HREE enrichment distribution patterns, low concentrations of Mn and Fe and negative Ce anomaly occur in the porewater, and high Mn/Al ratios and low U concentrations were observed in sediment, indicating oxic condition. LREE (Light REE) and MREE (Middle REE) enrichment in upper layer and depletion of MREE in deeper layer were shown in porewater profile. This study suggests that porewater flux in the western Pacific basin is a minor source of REEs to seawater, and abundant REEs are enriched in sediments, which is mainly caused by the extensive oxic condition, low sedimentation rate and strong adsorption capacity of sediments. Hence, the removal of REEs of porewater may result in widespread REE-rich sediments in the western Pacific basin.

  7. XAS and TRLIF spectroscopy of uranium and neptunium in seawater.

    Science.gov (United States)

    Maloubier, Melody; Solari, Pier Lorenzo; Moisy, Philippe; Monfort, Marguerite; Den Auwer, Christophe; Moulin, Christophe

    2015-03-28

    Seawater contains radionuclides at environmental levels; some are naturally present and others come from anthropogenic nuclear activity. In this report, the molecular speciation in seawater of uranium(VI) and neptunium(V) at a concentration of 5 × 10(-5) M has been investigated for the first time using a combination of two spectroscopic techniques: Time-resolved laser-induced fluorescence (TRLIF) for U and extended X-ray absorption fine structure (EXAFS) for U and Np at the LIII edge. In parallel, the theoretical speciation of uranium and neptunium in seawater at the same concentration is also discussed and compared to spectroscopic data. The uranium complex was identified as the neutral carbonato calcic complex UO2(CO3)3Ca2, which has been previously described in other natural systems. In the case of neptunium, the complex identified is mainly a carbonato complex whose exact stoichiometry is more difficult to assess. The knowledge of the actinide molecular speciation and reactivity in seawater is of fundamental interest in the particular case of uranium recovery and more generally regarding the actinide life cycle within the biosphere in the case of accidental release. This is the first report of actinide direct speciation in seawater medium that can complement inventory data.

  8. An exploratory study on seawater-catalysed urine phosphorus recovery (SUPR).

    Science.gov (United States)

    Dai, Ji; Tang, Wen-Tao; Zheng, Yi-Se; Mackey, Hamish R; Chui, Ho Kwong; van Loosdrecht, Mark C M; Chen, Guang-Hao

    2014-12-01

    Phosphorus (P) is a crucial and non-renewable resource, while it is excessively discharged via sewage, significant amounts originating from human urine. Recovery of P from source-separated urine presents an opportunity not only to recover this precious resource but also to improve downstream sewage treatment works. This paper proposes a simple and economic method to recover urine derived P by using seawater as a low-cost precipitant to form struvite, as Hong Kong has practised seawater toilet flushing as an alternative water resource since 1958. Chemical reactions, process conditions and precipitate composition for P precipitation in urine have been investigated to develop this new urine P recovery approach. This study concluded that ureolysis extent in a urine-seawater mixture determines the reaction pH that in turn influences the P recovery efficiency significantly; 98% of urine P can precipitate with seawater within 10 min when 40-75% of the urea in urine is ureolysed; the urine to seawater ratio alters the composition of the precipitates. The P content in the precipitates was found to be more than 9% when the urine fraction was 40% or higher. Magnesium ammonium phosphate (MAP) was confirmed to be the predominant component of the precipitates. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Cultivation of oleaginous Rhodotorula mucilaginosa in airlift bioreactor by using seawater.

    Science.gov (United States)

    Yen, Hong-Wei; Liao, Yu-Ting; Liu, Yi Xian

    2016-02-01

    The enormous water resource consumption is a concern to the scale-up fermentation process, especially for those cheap fermentation commodities, such as microbial oils as the feedstock for biodiesel production. The direct cultivation of oleaginous Rhodotorula mucilaginosa in a 5-L airlift bioreactor using seawater instead of pure water led to a slightly lower biomass being achieved, at 17.2 compared to 18.1 g/L, respectively. Nevertheless, a higher lipid content of 65 ± 5% was measured in the batch using seawater as compared to the pure water batch. Both the salinity and osmotic pressure decreased as the cultivation time increased in the seawater batch, and these effects may contribute to the high tolerance for salinity. No effects were observed for the seawater on the fatty acid profiles. The major components for both batches using seawater and pure water were C16:0 (palmitic acid), C18:1 (oleic acid) and C18:2 (linoleic acid), which together accounted for over 85% of total lipids. The results of this study indicated that seawater could be a suitable option for scaling up the growth of oleaginous R. mucilaginosa, especially from the perspective of water resource utilization. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  10. Corrosion and antifouling characteristics of technetium 99 in seawater

    International Nuclear Information System (INIS)

    Spitsyn, V.I.; Strekalov, P.V.; Balakhovskij, O.A.; Mikhajlovskij, Yu.N.

    1982-01-01

    The results are presented of studying the corrosive and antifouling properties of metallic technetium-99 in the Barents Sea and the Sea of Japan. Foil of 99 Tc glued on acrylic plastic served as a sample. High corrosion resistance and antifouling properties exhibited by 99 Tc in seawater point to favorable prospects of further studies aimed at development of new methods for protection against corrosion and fouling of metallic structures and parts with the use of technetium. The antifouling properties of technetium would evidently be used most efficiently when coating materials of high corrosion resistance to seawater (titanium, stainless steels, special alloys, etc.) with layers of technetium. The use of technetium for coating low-alloyed or carbon steels employed in seawater is yet problematic

  11. The status quo and the prospect of extraction of resources in seawater

    International Nuclear Information System (INIS)

    Katoh, Shunsaku

    1991-01-01

    Sea is the natural storage, and the enormous quantity of river water which contains the large amount of ions and compositions flows into sea, accordingly it has been calculated that seawater is replaced with new water in about 4 x 10 4 years. Sea is always agitated by tidal current, therefore, the composition of seawater is nearly uniform in most sea areas. Almost all elements existing in nature are dissolved in seawater, and the state of dissolution of main elements and their concentration are shown. The total quantity of seawater is as enormous as 1.35 x 10 9 km 3 , accordingly even in the trace elements in seawater, the total dissolved amount is enormous. For Japan which lacks resources, it is the important subject to develop the technology of effectively utilizing the resources in sea. The methods of obtaining sodium chloride, magnesium, bromine and potassium, which are the main components of seawater, are briefly explained. As the extraction of trace components, gold and silver, uranium, lithium, boron, strontium, vanadium, molybdenum, yttrium and heavy water are taken up. The optimal system must be built including the development of high performance adsorbents. (K.I.)

  12. Latent Toxicity of Endothall to Anadromous Salmonids During Seawater Challenge.

    Science.gov (United States)

    Courter, Lauren A; Garrison, Thomas M; Courter, Ian I

    2016-05-01

    Limited evidence exists on the latent effects of toxicant exposure on the seawater adaptability of anadromous salmon and steelhead. It is unclear whether such an effect exists for the widely used and relatively non-toxic herbicide endothall. Coho salmon, Oncorhynchus kisutch (coho), Chinook salmon, O. tshawytscha (Chinook), and anadromous rainbow trout, O. mykiss (steelhead) were subjected to a 10-day seawater challenge following freshwater treatments [0-12 mg acid equivalent (a.e)./L at 96 h]. Mean survival resulted in 82 % (n = 225), 84 % (n = 133), 90 % (n = 73) and 59 % (n = 147) survival for 0, 3-5, 6-8, and 9-12 mg a.e./L, respectively. Our results indicate a lower toxicity threshold compared with previously reported acute toxicity results, but higher compared with previous seawater challenge studies. We demonstrate the utility of the seawater challenge assay to accurately define toxic effects of pesticides on salmonids with complex life-histories.

  13. State-of-art report on the seawater desalination process

    International Nuclear Information System (INIS)

    Hwang, Young Dong; Kim, Young In; Lee, Doo Jung; Chang, Moon Hee

    2000-11-01

    Desalination technologies have been developed over the last 40 years and become a reliable industrial process for water production from sea or blackish water. At present, various desalination processes are available for the effective use of seawater or blackish water as valuable water resources. Since a large amount of energy is required for seawater desalination, the cost of energy is important for desalination. For the regions of severe water shortage, however, desalination is the most economical way of water supply compare to any other alternatives. Currently, water supply by seawater desalination is being increased in the areas of the Caribbean, North African and Middle East. Also, desalination of blackish water is being increased in the south-east region of USA. In general, the distillation process and the membrane technology are used for seawater esalination and the membrane and the electric-dialysis for blackish water. However, the selection of the desalination process is highly dependent on the use of produced water and the local environmental conditions where the desalination plant installed. The local condition is the most important parameters for the selection of the desalination process

  14. Removal of trihalomethane from chlorinated seawater using gamma radiation.

    Science.gov (United States)

    Rajamohan, R; Natesan, Usha; Venugopalan, V P; Rajesh, Puspalata; Rangarajan, S

    2015-12-01

    Chlorine addition as a biocide in seawater results in the formation of chlorination by-products such as trihalomethanes (THMs). Removal of THMs is of importance as they are potential mutagenic and carcinogenic agents. In this context, a study was conducted that used ionizing radiation to remove THMs from chlorinated (1, 3, and 5 mg/L) seawater by applying various dosages (0.4-5.0 kGy) of gamma radiation. Bromoform (BF) showed a faster rate of degradation as compared to other halocarbons such as bromodichloromethane (BDCM) and dibromochloromethane (DBCM). In chlorine-dosed seawater, total irradiation dose of 0.4 to 5 kGy caused percentage reduction in the range of 6.9 to 76.7%, 2.3 to 99.6%, and 45.7 to 98.3% for BDCM, DBCM, and BF, respectively. During the irradiation process, pH of the chlorinated seawater decreased with increase in the absorbed dose; however, no change in total organic carbon (TOC) was observed. The results show that gamma dose of 2.5 kGy was adequate for maximum degradation of THM; but for complete mineralization, higher dose would be required.

  15. State-of-art report on the seawater desalination process

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Young Dong; Kim, Young In; Lee, Doo Jung; Chang, Moon Hee

    2000-11-01

    Desalination technologies have been developed over the last 40 years and become a reliable industrial process for water production from sea or blackish water. At present, various desalination processes are available for the effective use of seawater or blackish water as valuable water resources. Since a large amount of energy is required for seawater desalination, the cost of energy is important for desalination. For the regions of severe water shortage, however, desalination is the most economical way of water supply compare to any other alternatives. Currently, water supply by seawater desalination is being increased in the areas of the Caribbean, North African and Middle East. Also, desalination of blackish water is being increased in the south-east region of USA. In general, the distillation process and the membrane technology are used for seawater esalination and the membrane and the electric-dialysis for blackish water. However, the selection of the desalination process is highly dependent on the use of produced water and the local environmental conditions where the desalination plant installed. The local condition is the most important parameters for the selection of the desalination process.

  16. Aragonite coating solutions (ACS) based on artificial seawater

    Science.gov (United States)

    Tas, A. Cuneyt

    2015-03-01

    Aragonite (CaCO3, calcium carbonate) is an abundant biomaterial of marine life. It is the dominant inorganic phase of coral reefs, mollusc bivalve shells and the stalactites or stalagmites of geological sediments. Inorganic and initially precipitate-free aragonite coating solutions (ACS) of pH 7.4 were developed in this study to deposit monolayers of aragonite spherules or ooids on biomaterial (e.g., UHMWPE, ultrahigh molecular weight polyethylene) surfaces soaked in ACS at 30 °C. The ACS solutions of this study have been developed for the surface engineering of synthetic biomaterials. The abiotic ACS solutions, enriched with calcium and bicarbonate ions at different concentrations, essentially mimicked the artificial seawater composition and started to deposit aragonite after a long (4 h) incubation period at the tropical sea surface temperature of 30 °C. While numerous techniques for the solution deposition of calcium hydroxyapatite (Ca10(PO4)6(OH)2), of low thermodynamic solubility, on synthetic biomaterials have been demonstrated, procedures related to the solution-based surface deposition of high solubility aragonite remained uncommon. Monolayers of aragonite ooids deposited at 30 °C on UHMWPE substrates soaked in organic-free ACS solutions were found to possess nano-structures similar to the mortar-and-brick-type botryoids observed in biogenic marine shells. Samples were characterized using SEM, XRD, FTIR, ICP-AES and contact angle goniometry.

  17. Rapid determination of total phenols in seawater by 4-aminoantipyrine colorimetry

    Digital Repository Service at National Institute of Oceanography (India)

    Kadam, A.N.; Bhangale, V.P.

    A rapid and efficient 4-aminoantipyrine (4-AAP) colorimetric method without any cleanup step to determine total phenols in seawater is described. Efficiency of the method for seawater using external addition of phenol concentrations with working...

  18. Decomposition of dilute residual active chlorine in sea-water

    International Nuclear Information System (INIS)

    Yoshinaga, Tetsutaro; Kawano, Kentaro; Yanagase, Kenjiro; Shiga, Akira

    1985-01-01

    Coastal industries such as power stations require enormous quantities of sea-water for cooling, but the marine organisms in it often result in fouling and/or blockade of the circulating water condenser and pipeworks. To prevent this, chlorine, or hypochlorite by the direct electrolysis of sea-water have been added. Environmental concerns, however, dictate that the residual chlorine concentration at the outlet should be less than the regulated value (0.02 ppm). Methods for decomposing dilute residual chlorine solutions were therefore studied. It was found that: 1) The addition of (raw) sea-water to the sea-water which passed through the condenser lowered the residual chlorine concentration to an greater extent than could be expected by dilution only. 2) Ozonation of the residual chlorine solution led to degradation of OCl - , but in solutions with a residual chlorine concentrations of less than 3 -- 4 ppm, ozonation had no effect. 3) Irradiation with ultra violet light (254 nm) decomposed the residual chlorine. Under the present work conditions (25 0 C: pH 8; depth 10 mm), nearly first order kinetics were to hold [da/dt = ksub((1)) (1-a)sup(n)]. There is a proportional relationship between the kinetic constant (k) and illuminous intensity (L), i.e., ksub((1))[C 0 sup(Cl 2 ): 10 ppm] = 6.56 x 10 -5 L (L = 0 -- 1000 lx). Thus, the use of both sea-water addition and UV irradiation provides a probable method for decomposing a residual chlorine to the expected concentration. (author)

  19. Modification of Optical Properties of Seawater Exposed to Oil Contaminants Based on Excitation-Emission Spectra

    Science.gov (United States)

    Baszanowska, E.; Otremba, Z.

    2015-10-01

    The optical behaviour of seawater exposed to a residual amount of oil pollution is presented and a comparison of the fluorescence spectra of oil dissolved in both n-hexane and seawater is discussed based on excitation-emission spectra. Crude oil extracted from the southern part of the Baltic Sea was used to characterise petroleum properties after contact with seawater. The wavelength-independent fluorescence maximum for natural seawater and seawater artificially polluted with oil were determined. Moreover, the specific excitation-emission peaks for natural seawater and polluted water were analysed to identify the natural organic matter composition. It was found that fluorescence spectra identification is a promising method to detect even an extremely low concentration of petroleum residues directly in the seawater. In addition, alien substances disturbing the fluorescence signatures of natural organic substances in a marine environment is also discussed.

  20. Recovery of uranium from seawater. 14. System arrangements for the recovery of uranium from seawater by spherical amidoxime chelating resins utilizing natural seawater motions

    International Nuclear Information System (INIS)

    Egawa, Hiroaki; Kabay, Nalan; Shuto, Taketomi; Jyo, Akinori

    1993-01-01

    In order to evaluate performances of lightly cross-linked highly porous amidoxime resins in uranium-adsorption systems utilizing natural seawater motions, uranium uptake by the resins from seawater was studied by different approaches, such as simulated sea current exposure tests, towing trials, and/or mooring trials. In general, the efficiency of uranium uptake became higher with a decrease in the thickness of packing layers, indicating important roles of fluidization of the resin particles. On the basis of these fundamental data, mooring tests in the natural sea current were designed and conducted. By mooring flat adsorption beds (base area 260 cm 2 , height 3.0 cm) packed with 780 ml of the resin for 40 h, promising uranium uptake as high as 44 mg/kg of resin (9.9 mg/l of resin) was achieved under sea conditions in which the velocity of sea currents and the vertical velocity of waves were 5.5-49.7 cm/s and 3.4-27 cm/s, respectively

  1. Seawater immersion aggravates burn-associated lung injury and inflammatory and oxidative-stress responses.

    Science.gov (United States)

    Ma, Jun; Wang, Ying; Wu, Qi; Chen, Xiaowei; Wang, Jiahan; Yang, Lei

    2017-08-01

    With the increasing frequency of marine development activities and local wars at sea, the incidence of scald burns in marine accidents or wars has been increasing yearly. Various studies have indicated that immersion in seawater has a systemic impact on some organs of animals or humans with burn. Thus, for burn/scald injuries after immersion in seawater, it is desirable to study the effects and mechanisms of action on important organs. In the present study, we aimed to investigate the effect of immersion in seawater on lung injury, inflammatory and oxidative-stress responses in scalded rats. The structural damage to lungs was detected by hematoxylin and eosin staining and the results showed that seawater immersion aggravated structural lung injury in scalded rats. The expression of HMGB1 in lung tissues was detected by immunohistochemical analysis and the results showed that seawater immersion increased HMGB1 expression in lung tissues of scalded rats. Apoptosis in lung tissues was detected by terminal deoxynucleotidyl transfer-mediated dUTP nick end-labeling (TUNEL) staining and the results showed that seawater immersion increased apoptosis rate in lung tissues of scalded rats. In addition, the expression levels of TNF-α, IL-6, IL-8, SOD, and MDA in serum were analyzed by enzyme-linked immunosorbent assays (ELISAs) and the results showed that seawater immersion induced secretion of proinflammatory factors (TNF-α, IL-6, and IL-8), increased MDA protein level, and suppressed SOD activity in the serum of scalded rats. Furthermore, measurement of plasma volume and pH showed that seawater immersion decreased plasma volume and pH value. Overall, the results indicated that all effects induced by immersion in seawater in scalded rats are more pronounced than those induced by freshwater. In conclusion, seawater immersion may aggravate lung injury and enhance inflammatory and oxidative-stress responses after burn. Copyright © 2017 Elsevier Ltd and ISBI. All rights

  2. Cell Culture Isolation of Piscine Nodavirus (Betanodavirus) in Fish-Rearing Seawater.

    Science.gov (United States)

    Nishi, Shinnosuke; Yamashita, Hirofumi; Kawato, Yasuhiko; Nakai, Toshihiro

    2016-04-01

    Piscine nodavirus (betanodavirus) is the causative agent of viral nervous necrosis (VNN) in a variety of cultured fish species, particularly marine fish. In the present study, we developed a sensitive method for cell culture isolation of the virus from seawater and applied the method to a spontaneous fish-rearing environment. The virus in seawater was concentrated by an iron-based flocculation method and subjected to isolation with E-11 cells. A real-time reverse transcriptase PCR (RT-PCR) assay was used to quantify the virus in water. After spiking into seawater was performed, a betanodavirus strain (red spotted grouper nervous necrosis virus [RGNNV] genotype) was effectively recovered in the E-11 cells at a detection limit of approximately 10(5)copies (equivalent to 10(2)50% tissue culture infective doses [TCID50])/liter seawater. In an experimental infection of juvenile sevenband grouper (Epinephelus septemfasciatus) with the virus, the virus was isolated from the drainage of a fish-rearing tank when the virus level in water was at least approximately 10(5)copies/liter. The application of this method to seven band grouper-rearing floating net pens, where VNN prevailed, resulted in the successful isolation of the virus from seawater. No differences were found in the partial sequences of the coat protein gene (RNA2) between the clinical virus isolates of dead fish and the cell-cultured virus isolates from seawater, and the viruses were identified as RGNNV. The infection experiment showed that the virus isolates from seawater were virulent to seven band grouper. These results showed direct evidence of the horizontal transmission of betanodavirus via rearing water in marine aquaculture. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  3. Potential energy surface, dipole moment surface and the intensity calculations for the 10 μm, 5 μm and 3 μm bands of ozone

    Science.gov (United States)

    Polyansky, Oleg L.; Zobov, Nikolai F.; Mizus, Irina I.; Kyuberis, Aleksandra A.; Lodi, Lorenzo; Tennyson, Jonathan

    2018-05-01

    Monitoring ozone concentrations in the Earth's atmosphere using spectroscopic methods is a major activity which undertaken both from the ground and from space. However there are long-running issues of consistency between measurements made at infrared (IR) and ultraviolet (UV) wavelengths. In addition, key O3 IR bands at 10 μm, 5 μm and 3 μm also yield results which differ by a few percent when used for retrievals. These problems stem from the underlying laboratory measurements of the line intensities. Here we use quantum chemical techniques, first principles electronic structure and variational nuclear-motion calculations, to address this problem. A new high-accuracy ab initio dipole moment surface (DMS) is computed. Several spectroscopically-determined potential energy surfaces (PESs) are constructed by fitting to empirical energy levels in the region below 7000 cm-1 starting from an ab initio PES. Nuclear motion calculations using these new surfaces allow the unambiguous determination of the intensities of 10 μm band transitions, and the computation of the intensities of 10 μm and 5 μm bands within their experimental error. A decrease in intensities within the 3 μm is predicted which appears consistent with atmospheric retrievals. The PES and DMS form a suitable starting point both for the computation of comprehensive ozone line lists and for future calculations of electronic transition intensities.

  4. Effects of electrode settings on chlorine generation efficiency of electrolyzing seawater.

    Science.gov (United States)

    Hsu, Guoo-Shyng Wang; Hsia, Chih-Wei; Hsu, Shun-Yao

    2015-12-01

    Electrolyzed water has significant disinfection effects, can comply with food safety regulations, and is environmental friendly. We investigated the effects of immersion depth of electrodes, stirring, electrode size, and electrode gap on the properties and chlorine generation efficiency of electrolyzing seawater and its storage stability. Results indicated that temperature and oxidation-reduction potential (ORP) of the seawater increased gradually, whereas electrical conductivity decreased steadily in electrolysis. During the electrolysis process, pH values and electric currents also decreased slightly within small ranges. Additional stirring or immersing the electrodes deep under the seawater significantly increased current density without affecting its electric efficiency and current efficiency. Decreasing electrode size or increasing electrode gap decreased chlorine production and electric current of the process without affecting its electric efficiency and current efficiency. Less than 35% of chlorine in the electrolyzed seawater was lost in a 3-week storage period. The decrement trend leveled off after the 1 st week of storage. The electrolyzing system is a convenient and economical method for producing high-chlorine seawater, which will have high potential applications in agriculture, aquaculture, or food processing. Copyright © 2015. Published by Elsevier B.V.

  5. Effects of electrode settings on chlorine generation efficiency of electrolyzing seawater

    Directory of Open Access Journals (Sweden)

    Guoo-Shyng Wang Hsu

    2015-12-01

    Full Text Available Electrolyzed water has significant disinfection effects, can comply with food safety regulations, and is environmental friendly. We investigated the effects of immersion depth of electrodes, stirring, electrode size, and electrode gap on the properties and chlorine generation efficiency of electrolyzing seawater and its storage stability. Results indicated that temperature and oxidation-reduction potential (ORP of the seawater increased gradually, whereas electrical conductivity decreased steadily in electrolysis. During the electrolysis process, pH values and electric currents also decreased slightly within small ranges. Additional stirring or immersing the electrodes deep under the seawater significantly increased current density without affecting its electric efficiency and current efficiency. Decreasing electrode size or increasing electrode gap decreased chlorine production and electric current of the process without affecting its electric efficiency and current efficiency. Less than 35% of chlorine in the electrolyzed seawater was lost in a 3-week storage period. The decrement trend leveled off after the 1st week of storage. The electrolyzing system is a convenient and economical method for producing high-chlorine seawater, which will have high potential applications in agriculture, aquaculture, or food processing.

  6. Online preconcentration ICP-MS analysis of rare earth elements in seawater

    Science.gov (United States)

    Hathorne, Ed C.; Haley, Brian; Stichel, Torben; Grasse, Patricia; Zieringer, Moritz; Frank, Martin

    2012-01-01

    The rare earth elements (REEs) with their systematically varying properties are powerful tracers of continental inputs, particle scavenging intensity and the oxidation state of seawater. However, their generally low (˜pmol/kg) concentrations in seawater and fractionation potential during chemical treatment makes them difficult to measure. Here we report a technique using an automated preconcentration system, which efficiently separates seawater matrix elements and elutes the preconcentrated sample directly into the spray chamber of an ICP-MS instrument. The commercially available "seaFAST" system (Elemental Scientific Inc.) makes use of a resin with ethylenediaminetriacetic acid and iminodiacetic acid functional groups to preconcentrate REEs and other metals while anions and alkali and alkaline earth cations are washed out. Repeated measurements of seawater from 2000 m water depth in the Southern Ocean allows the external precision (2σ) of the technique to be estimated at mine water reference materials diluted with a NaCl matrix with recommended values in the literature. This makes the online preconcentration ICP-MS technique advantageous for the minimal sample preparation required and the relatively small sample volume consumed (7 mL) thus enabling large data sets for the REEs in seawater to be rapidly acquired.

  7. Impact of Cyclic Loading on Chloride Diffusivity and Mechanical Performance of RC Beams under Seawater Corrosion

    Directory of Open Access Journals (Sweden)

    Sen Pang

    2017-01-01

    Full Text Available An experimental study was conducted to investigate the impact of cyclic loading on the mechanical performance and chloride diffusivity of RC beams exposed to seawater wet-dry cycles. To induce initial damage to RC beam specimen, cyclic loading controlled by max load and cycles was applied. Then beam specimens underwent 240 wet-dry cycles of seawater. Results show that the chloride content increased as max load and cycle increased. The chloride content at steel surface increased approximatively linearly as average crack width increased. Moreover, the max load had more influence on chloride content at steel surface than cycle. The difference of average chloride diffusion coefficient between tension and compression concrete was little at uncracked position. Average chloride diffusion coefficient increased as crack width increased when crack width was less than 0.11 mm whereas the increasing tendency was weak when crack width exceeded 0.11 mm. The residual yield load and ultimate load of RC beams decreased as max load and cycle increased. Based on univariate analysis of variance, the max load had more adverse effect on yield load and ultimate load than cycle.

  8. Extraction of uranium from seawater: chemical process and plant design feasibility study

    International Nuclear Information System (INIS)

    Campbell, M.H.; Frame, J.M.; Dudey, N.D.; Kiel, G.R.; Mesec, V.; Woodfield, F.W.; Binney, S.E.; Jante, M.R.; Anderson, R.C.; Clark, G.T.

    1979-02-01

    A major assessment was made of the uranium resources in seawater. Several concepts for moving seawater to recover the uranium were investigated, including pumping the seawater and using natural ocean currents or tides directly. The optimal site chosen was on the southeastern Puerto Rico coast, with the south U.S. Atlantic coast as an alternate. The various processes for extracting uranium from seawater were reviewed, with the adsorption process being the most promising at the present time. Of the possible adsorbents, hydrous titanium oxide was found to have the best properties. A uranium extraction plant was conceptually designed. Of the possible methods for contacting the seawater with the adsorbent, a continuous fluidized bed concept was chosen as most practical for a pumped system. A plant recovering 500 tonnes of U 3 O 8 per year requires 5900 cubic meters per second of seawater to be pumped through the adsorbent beds for a 70% overall recovery efficiency. Total cost of the plant was estimated to be about $6.2 billion. A computer model for the process was used for parametric sensitivity studies and economic projections. Several design case variations were developed. Other topics addressed were the impact of co-product recovery, environmental considerations, etc

  9. Extraction of uranium from seawater: chemical process and plant design feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, M.H.; Frame, J.M.; Dudey, N.D.; Kiel, G.R.; Mesec, V.; Woodfield, F.W.; Binney, S.E.; Jante, M.R.; Anderson, R.C.; Clark, G.T.

    1979-02-01

    A major assessment was made of the uranium resources in seawater. Several concepts for moving seawater to recover the uranium were investigated, including pumping the seawater and using natural ocean currents or tides directly. The optimal site chosen was on the southeastern Puerto Rico coast, with the south U.S. Atlantic coast as an alternate. The various processes for extracting uranium from seawater were reviewed, with the adsorption process being the most promising at the present time. Of the possible adsorbents, hydrous titanium oxide was found to have the best properties. A uranium extraction plant was conceptually designed. Of the possible methods for contacting the seawater with the adsorbent, a continuous fluidized bed concept was chosen as most practical for a pumped system. A plant recovering 500 tonnes of U/sub 3/O/sub 8/ per year requires 5900 cubic meters per second of seawater to be pumped through the adsorbent beds for a 70% overall recovery efficiency. Total cost of the plant was estimated to be about $6.2 billion. A computer model for the process was used for parametric sensitivity studies and economic projections. Several design case variations were developed. Other topics addressed were the impact of co-product recovery, environmental considerations, etc.

  10. Bactericidal effect of blue LED light irradiated TiO2/Fe3O4 particles on fish pathogen in seawater

    International Nuclear Information System (INIS)

    Cheng, T.C.; Yao, K.S.; Yeh, N.; Chang, C.I.; Hsu, H.C.; Gonzalez, F.; Chang, C.Y.

    2011-01-01

    This study uses blue LED light (λ max = 475 nm) activated TiO 2 /Fe 3 O 4 particles to evaluate the particles' photocatalytic activity efficiency and bactericidal effects in seawater of variable salinities. Different TiO 2 to Fe 3 O 4 mole ratios have been synthesized using sol-gel method. The synthesized particles contain mainly anatase TiO 2 , Fe 3 O 4 and FeTiO 3 . The study has identified TiO 2 /Fe 3 O 4 's bactericidal effect to marine fish pathogen (Photobacterium damselae subsp. piscicida BCRC17065) in seawater. The SEM photo reveals the surface destruction in bacteria incubated with blue LED irradiated TiO 2 /Fe 3 O 4 . The result of this study indicates that 1) TiO 2 /Fe 3 O 4 acquires photocatalytic activities in both the freshwater and the seawater via blue LED irradiation, 2) higher photocatalytic activities appear in solutions of higher TiO 2 /Fe 3 O 4 mole ratio, and 3) photocatalytic activity decreases as salinity increases. These results suggest that the energy saving blue LED light is a feasible light source to activate TiO 2 /Fe 3 O 4 photocatalytic activities in both freshwater and seawater.

  11. Anion-exchange enrichment and spectrophotometric determination of uranium in sea-water

    International Nuclear Information System (INIS)

    Kuroda, Rokuro; Oguma, Koichi; Mukai, Noriko; Iwamoto, Masatoshi

    1987-01-01

    A method is proposed for the determination of uranium in sea-water. The uranium is strongly sorbed on a strongly basic anion-exchange resin (Cl - form) from acidified sea-water containing sodium azide (0.3M) and is easily eluted with 1M hydrochloric acid. Uranium in the effluent can be determined spectrophotometrically with Arsenazo III. The combined method allows easy and selective determination of uranium in sea-water without using a sophisticated adsorbent. The overall recovery and precision are satisfactory at the 3 μg/1. level. (author)

  12. The nuclear energy in the seawater desalination

    International Nuclear Information System (INIS)

    Moreno A, J.; Flores E, R.M.

    2004-01-01

    In general, the hydric resources of diverse regions of the world are insufficient for to satisfy the necessities of their inhabitants. Among the different technologies that are applied for the desalination of seawater are the distillation processes, the use of membranes and in particular recently in development the use of the nuclear energy (Nuclear Desalination; System to produce drinkable water starting from seawater in a complex integrated in that as much the nuclear reactor as the desalination system are in a common location, the facilities and pertinent services are shared, and the nuclear reactor produces the energy that is used for the desalination process). (Author)

  13. Seawater Immersion of GEM II Propellant

    National Research Council Canada - National Science Library

    Merrill, Calude

    1999-01-01

    ... (% AP lost/week aged in seawater) and intercepts that depend on sample size. Friction and impact data on dried aged propellant samples showed no increased burning hazard compared with propellant not exposed to water...

  14. Investigation of adsorbers for the extracting of uranium from seawater

    International Nuclear Information System (INIS)

    Witte, E.G.; Astheimer, L.; Schenk, H.J.; Schwochau, K.

    1979-01-01

    Organic ion exchangers have been tested with respect to their efficiency uranium from seawater. A complexing polymer resin which combines fast uptake of uranium with high selectivity is found to be able to accumulate uranium from natural seawater by a factor of 2.6 x 10 5 . (orig.) 891 HK/orig. 892 MKO [de

  15. A new approach for determination of fouling potential by colloidal nanoparticles during reverse osmosis (RO) membrane filtration of seawater

    International Nuclear Information System (INIS)

    Park, Ji Yeon; Lim, Sungil; Park, Kihong

    2013-01-01

    A direct measurement of number concentration of colloidal nanoparticles (15–450 nm) in water was made with the membrane filtration-differential mobility analyzer technique, and its corresponding flux decline rate (FDR) was determined by laboratory-scale RO fouling test unit using varying number concentrations of silica nanoparticles in artificial seawaters. This relationship was used to predict fouling potential of colloidal nanoparticles in reverse osmosis (RO) membrane process of seawaters in RO plant. It was found that the FDR linearly increased with the increasing number of colloidal nanoparticles for the given concentration range and that the relationship between the number concentration and the FDR also depended on RO membrane surface properties. Data for estimated FDR values for natural seawaters after pretreatment showed a clear difference among samples, which is contrary to the pre-existing index such as silt density index and modified fouling index. Our data suggest that measurement of colloidal nanoparticles is useful for selection of proper pretreatment and successful operation of RO membrane process along with other particle fouling predictors accounting for large particles (>450 nm).

  16. A new approach for determination of fouling potential by colloidal nanoparticles during reverse osmosis (RO) membrane filtration of seawater

    Energy Technology Data Exchange (ETDEWEB)

    Park, Ji Yeon; Lim, Sungil; Park, Kihong, E-mail: kpark@gist.ac.kr [Gwangju Institute of Science and Technology (GIST), School of Environmental Science and Engineering (Korea, Republic of)

    2013-04-15

    A direct measurement of number concentration of colloidal nanoparticles (15-450 nm) in water was made with the membrane filtration-differential mobility analyzer technique, and its corresponding flux decline rate (FDR) was determined by laboratory-scale RO fouling test unit using varying number concentrations of silica nanoparticles in artificial seawaters. This relationship was used to predict fouling potential of colloidal nanoparticles in reverse osmosis (RO) membrane process of seawaters in RO plant. It was found that the FDR linearly increased with the increasing number of colloidal nanoparticles for the given concentration range and that the relationship between the number concentration and the FDR also depended on RO membrane surface properties. Data for estimated FDR values for natural seawaters after pretreatment showed a clear difference among samples, which is contrary to the pre-existing index such as silt density index and modified fouling index. Our data suggest that measurement of colloidal nanoparticles is useful for selection of proper pretreatment and successful operation of RO membrane process along with other particle fouling predictors accounting for large particles (>450 nm).

  17. Process for enriching uranium from seawater

    International Nuclear Information System (INIS)

    Heitkamp, D.; Inden, P.

    1982-01-01

    In selective elutriation of uranium deposited on titanium oxide hydrate by carbonate solution, only uranium should be dissolved from the absorption material forming carbonate compounds, without the deposited ballast ions, above all of magnesium, calcium and sodium being elutriated. The uranium elutriation according to the invention is therefore carried out in the presence of these ballast ions in the same concentrations as those in seawater. The carbonate concentration can only be raised as far as the solubility product of the basic magnesium carbonate permits, so that magnesium remains in the solution, as well as carbonate, in the concentration present in seawater. One must accept the absence of calcium ions in the elutriation solution, as their solubility product with carbonate is considerably less than that for magnesium. (orig./PW) [de

  18. Efficiency improvement of seawater desalination processes: the case of the W.E.B. Aruba N.V. on the island of Aruba

    NARCIS (Netherlands)

    Marchena, F.A.

    2013-01-01

    Seawater desalination is known worldwide as the most important source for the production of drinking water in arid areas where there are practically no natural water resources and consequently insufficient surface water or groundwater. However the desalination technology still remains a very costly

  19. A solvent extraction technique for the isotopic measurement of dissolved copper in seawater

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Claire M., E-mail: claire.thompson@anu.edu.au; Ellwood, Michael J., E-mail: michael.ellwood@anu.edu.au; Wille, Martin, E-mail: martin.wille@uni-tuebingen.de

    2013-05-02

    Graphical abstract: -- Highlights: •A new sample preparation method for seawater copper isotopic analysis (δ{sup 65}Cu). •Solvent-extraction was used to pre-concentrate metals from seawater samples. •Anion-exchange was used to purify copper from the metal-rich extract. •δ{sup 65}Cu was measured in the north Tasman Sea. •Seawater δ{sup 65}Cu may be linked to marine biological activity. -- Abstract: Stable copper (Cu) isotope geochemistry provides a new perspective for investigating and understanding Cu speciation and biogeochemical Cu cycling in seawater. In this work, sample preparation for isotopic analysis employed solvent-extraction with amino pyrollidine dithiocarbamate/diethyl dithiocarbamate (APDC/DDC), coupled with a nitric acid back-extraction, to concentrate Cu from seawater. This was followed by Cu-purification using anion-exchange. This straightforward technique is high yielding and fractionation free for Cu and allows precise measurement of the seawater Cu isotopic composition using multi-collector inductively coupled plasma mass-spectrometry. A deep-sea profile measured in the oligotrophic north Tasman Sea shows fractionation in the Cu isotopic signature in the photic zone but is relatively homogenised at depth. A minima in the Cu isotopic profile correlates with the chlorophyll a maximum at the site. These results indicate that a range of processes are likely to fractionate stable Cu isotopes in seawater.

  20. Predicting and measurement of pH of seawater reverse osmosis concentrates

    KAUST Repository

    Waly, Tarek; Kennedy, Maria Dolores; Witkamp, Geert-Jan; Amy, Gary L.; Schippers, Jan Cornelis

    2011-01-01

    The pH of seawater reverse osmosis plants (SWRO) is the most influential parameter in determining the degree of supersaturation of CaCO3 in the concentrate stream. For this, the results of pH measurements of the concentrate of a seawater reverse