Changes in Sea Salt Emissions Enhance ENSO Variability

Energy Technology Data Exchange (ETDEWEB)

Yang, Yang; Russell, Lynn M.; Lou, Sijia; Lamjiri, Maryam A.; Liu, Ying; Singh, Balwinder; Ghan, Steven J.

2016-11-15

Two 150-year pre-industrial simulations with and without interactive sea salt emissions from the Community Earth System Model (CESM) are performed to quantify the interactions between sea salt emissions and El Niño–Southern Oscillation (ENSO). Variations in sea salt emissions over the tropical Pacific Ocean are affected by changing wind speed associated with ENSO variability. ENSO-induced interannual variations in sea salt emissions result in decreasing (increasing) aerosol optical depth (AOD) by 0.03 over the equatorial central-eastern (western) Pacific Ocean during El Niño events compared to those during La Niña events. These changes in AOD further increase (decrease) radiative fluxes into the atmosphere by +0.2 W m^-2 (-0.4 W m^-2) over the tropical eastern (western) Pacific. Thereby, sea surface temperature increases (decreases) by 0.2–0.4 K over the tropical eastern (western) Pacific Ocean during El Niño compared to La Niña events and enhances ENSO variability by 10%. The increase in ENSO amplitude is a result of systematic heating (cooling) during the warm (cold) phase, of ENSO in the eastern Pacific. Interannual variations in sea salt emissions then produce the anomalous ascent (subsidence) over the equatorial eastern (western) Pacific between El Niño and La Niña events, which is a result of heating anomalies. Due to variations in sea salt emissions, the convective precipitation is enhanced by 0.6–1.2 mm day^-1 over the tropical central-eastern Pacific Ocean and weakened by 0.9–1.5 mm day^-1 over the Maritime Continent during El Niño compared to La Niña events, enhancing the precipitation variability over the tropical Pacific.

Variability of sea salts in ice and firn cores from Fimbul Ice Shelf, Dronning Maud Land, Antarctica

Science.gov (United States)

Paulina Vega, Carmen; Isaksson, Elisabeth; Schlosser, Elisabeth; Divine, Dmitry; Martma, Tõnu; Mulvaney, Robert; Eichler, Anja; Schwikowski-Gigar, Margit

2018-05-01

Major ions were analysed in firn and ice cores located at Fimbul Ice Shelf (FIS), Dronning Maud Land - DML, Antarctica. FIS is the largest ice shelf in the Haakon VII Sea, with an extent of approximately 36 500 km2. Three shallow firn cores (about 20 m deep) were retrieved in different ice rises, Kupol Ciolkovskogo (KC), Kupol Moskovskij (KM), and Blåskimen Island (BI), while a 100 m long core (S100) was drilled near the FIS edge. These sites are distributed over the entire FIS area so that they provide a variety of elevation (50-400 m a.s.l.) and distance (3-42 km) to the sea. Sea-salt species (mainly Na+ and Cl-) generally dominate the precipitation chemistry in the study region. We associate a significant sixfold increase in median sea-salt concentrations, observed in the S100 core after the 1950s, to an enhanced exposure of the S100 site to primary sea-salt aerosol due to a shorter distance from the S100 site to the ice front, and to enhanced sea-salt aerosol production from blowing salty snow over sea ice, most likely related to the calving of Trolltunga occurred during the 1960s. This increase in sea-salt concentrations is synchronous with a shift in non-sea-salt sulfate (nssSO42-) toward negative values, suggesting a possible contribution of fractionated aerosol to the sea-salt load in the S100 core most likely originating from salty snow found on sea ice. In contrast, there is no evidence of a significant contribution of fractionated sea salt to the ice-rises sites, where the signal would be most likely masked by the large inputs of biogenic sulfate estimated for these sites. In summary, these results suggest that the S100 core contains a sea-salt record dominated by the proximity of the site to the ocean, and processes of sea ice formation in the neighbouring waters. In contrast, the ice-rises firn cores register a larger-scale signal of atmospheric flow conditions and a less efficient transport of sea-salt aerosols to these sites. These findings are a

Sensitivity of modeled atmospheric nitrogen species and nitrogen deposition to variations in sea salt emissions in the North Sea and Baltic Sea regions

Directory of Open Access Journals (Sweden)

D. Neumann

2016-03-01

Full Text Available Coarse sea salt particles are emitted ubiquitously from the ocean surface by wave-breaking and bubble-bursting processes. These particles impact the atmospheric chemistry by affecting the condensation of gas-phase species and, thus, indirectly the nucleation of new fine particles, particularly in regions with significant air pollution. In this study, atmospheric particle concentrations are modeled for the North Sea and Baltic Sea regions in northwestern Europe using the Community Multiscale Air Quality (CMAQ modeling system and are compared to European Monitoring and Evaluation Programme (EMEP measurement data. The sea salt emission module is extended by a salinity-dependent scaling of the sea salt emissions because the salinity in large parts of the Baltic Sea is very low, which leads to considerably lower sea salt mass emissions compared to other oceanic regions. The resulting improvement in predicted sea salt concentrations is assessed. The contribution of surf zone emissions is considered separately. Additionally, the impacts of sea salt particles on atmospheric nitrate and ammonium concentrations and on nitrogen deposition are evaluated. The comparisons with observational data show that sea salt concentrations are commonly overestimated at coastal stations and partly underestimated farther inland. The introduced salinity scaling improves the predicted Baltic Sea sea salt concentrations considerably. The dates of measured peak concentrations are appropriately reproduced by the model. The impact of surf zone emissions is negligible in both seas. Nevertheless, they might be relevant because surf zone emissions were cut at an upper threshold in this study. Deactivating sea salt leads to minor increases in NH3 +  NH4+ and HNO3 +  NO3− and a decrease in NO3− concentrations. However, the overall effect on NH3 +  NH4+ and HNO3 +  NO3− concentrations is smaller than the deviation from the measurements. Nitrogen wet deposition is

Salt marsh persistence is threatened by predicted sea-level rise

Science.gov (United States)

Crosby, Sarah C.; Sax, Dov F.; Palmer, Megan E.; Booth, Harriet S.; Deegan, Linda A.; Bertness, Mark D.; Leslie, Heather M.

2016-11-01

Salt marshes buffer coastlines and provide critical ecosystem services from storm protection to food provision. Worldwide, these ecosystems are in danger of disappearing if they cannot increase elevation at rates that match sea-level rise. However, the magnitude of loss to be expected is not known. A synthesis of existing records of salt marsh elevation change was conducted in order to consider the likelihood of their future persistence. This analysis indicates that many salt marshes did not keep pace with sea-level rise in the past century and kept pace even less well over the past two decades. Salt marshes experiencing higher local sea-level rise rates were less likely to be keeping pace. These results suggest that sea-level rise will overwhelm most salt marshes' capacity to maintain elevation. Under the most optimistic IPCC emissions pathway, 60% of the salt marshes studied will be gaining elevation at a rate insufficient to keep pace with sea-level rise by 2100. Without mitigation of greenhouse gas emissions this potential loss could exceed 90%, which will have substantial ecological, economic, and human health consequences.

Fourier transform near-infrared spectroscopy application for sea salt quality evaluation.

Science.gov (United States)

Galvis-Sánchez, Andrea C; Lopes, João Almeida; Delgadillo, Ivonne; Rangel, António O S S

2011-10-26

Near-infrared (NIR) spectroscopy in diffuse reflectance mode was explored with the objective of discriminating sea salts according to their quality type (traditional salt vs "flower of salt") and geographical origin (Atlantic vs Mediterranean). Sea salts were also analyzed in terms of Ca(2+), Mg(2+), K(+), alkalinity, and sulfate concentrations to support spectroscopic results. High concentrations of Mg(2+) and K(+) characterized Atlantic samples, while a high Ca(2+) content was observed in traditional sea salts. A partial least-squares discriminant analysis model considering the 8500-7500 cm(-1) region permitted the discrimination of salts by quality types. The regions 4650-4350 and 5900-5500 cm(-1) allowed salts classification according to their geographical origin. It was possible to classify correctly 85.3 and 94.8% of the analyzed samples according to the salt type and to the geographical origin, respectively. These results demonstrated that NIR spectroscopy is a suitable and very efficient tool for sea salt quality evaluation.

Microbial Growth in the Magnesium- Chloride - Sodium- Sulphate Ion System: Implications for Habitability in Terrestrial and Extraterrestrial Salts

Science.gov (United States)

Loudon, C. M.; Aka, S.; Cockell, C. S.

2017-12-01

Icy moons in the outer solar system are key targets in the search for extra-terrestrial life as there is evidence that they harbour subsurface oceans. Observational evidence of icy moons such as Europa suggest that these likely brine oceans should be composed of chloride and sulphate salts. The effects of the ions that compose these salts on biology and how the interactions between them can create geochemical and geophysical barriers to life are poorly understood. Here we present an in depth study of four microorganisms grown in solutions with varying combinations of the magnesium- chloride- sodium- sulphate ions. We find that the ion composition of the brine solution can have a large effect on growth. Whilst the water activity must be permissible for growth we found that this alone could not predict the effects of the ions on growth, chaotropic effects and ion specific effects influenced by the specific physiology of organisms are also evident. For this reason we conclude that simply knowing which salts are present on icy moons is not sufficient information to determine their potential habitibility. A full sample of any brine ocean would need to be studied to fully determine the potential for biology on these outer solar system satellites.

Interannual Variability of the Sea-Ice-Induced Salt Flux in the Greenland Sea

DEFF Research Database (Denmark)

Pedersen, Leif Toudal; Coon, M.D.

2001-01-01

The Greenland Sea is one of the few places in the World Ocean where deep convection takes place. The convection process is initiated by a density increase originating from rapid cooling and/or a salt flux to the upper layer of the ocean due to brine rejection from ice formation (Rudels, 1990......; Visbeck and others, 1995). The predominant ice types in the Greenland Sea arc frazil/grease ice and pancake ice. A numerical model has been developed relating ice formation and decay of these ice types as observed by the SMMR and SSM/I microwave radiometers and evaluating their contribution to salt...... redistribution in the Greenland Sea. The model has been used to calculate spatial distribution of the annual integrated net salt flux to the Greenland Sea from ice production and advection for the period 1979-97....

New method for recognition of sterol signalling molecules: Methinium salts as receptors for sulphated steroids

Czech Academy of Sciences Publication Activity Database

Kejík, Z.; Bříza, T.; Králová, Jarmila; Mikula, I.; Poučková, P.; Martásek, P.; Král, V.

2015-01-01

Roč. 94, February 2015 (2015), s. 15-20 ISSN 1878-5867 R&D Projects: GA TA ČR(CZ) TE01020028; GA ČR(CZ) GAP303/11/1291; GA MŠk(CZ) LH14008; GA MŠk(CZ) CZ.1.07/2.300/30.0060; GA MŠk(CZ) ED1.1.00/02.0109 Institutional support: RVO:68378050 Keywords : Polymethinium salts * Sulphated sterols * Molecular recognition * Synthetic receptors Subject RIV: EB - Genetics ; Molecular Biology

Sulphate reduction in the Aespoe HRL tunnel

International Nuclear Information System (INIS)

Gustafson, G.; Pedersen, K.; Tullborg, E.L.; Wallin, B.; Wikberg, P.

1995-12-01

Evidence and indications of sulphate reduction based on geological, hydrogeological, groundwater, isotope and microbial data gathered in and around the Aespoe Hard Rock Laboratory tunnel have been evaluated. This integrated investigation showed that sulphate reduction had taken place in the past but is most likely also an ongoing process. Anaerobic sulphate-reducing bacteria can live in marine sediments, in the tunnel sections under the sea and in deep groundwaters, since there is no access to oxygen. The sulphate-reducing bacteria seem to thrive when the Cl - concentration of the groundwater is 4000-6000 mg/l. Sulphate reduction is an in situ process but the resulting hydrogen-sulphide rich water can be transported to other locations. A more vigorous sulphate reduction takes place when the organic content in the groundwater is high (>10 mg/l DOC) which is the case in the sediments and in the groundwaters under the sea. Some bacteria use hydrogen as an electron donor instead of organic carbon and can therefore live in deep environments where access to organic material is limited. The sulphate-reducing bacteria seem to adapt to changing flow situations caused by the tunnel construction relatively fast. Sulphate reduction seems to have occurred and will probably occur where conditions are favourable for the sulphate-reducing bacteria such as anaerobic brackish groundwater with dissolved sulphate and organic carbon or hydrogen. 59 refs, 37 figs, 6 tabs

Influence of mineral salts upon activity of Trichoderma harzianum non-volatile metabolites on Armillaria spp. rhizomorphs

Directory of Open Access Journals (Sweden)

Krystyna Przybył

2011-01-01

Full Text Available Effect of non-volatile metabolites of Trichoderma harzianum together with certain salts containing Mg++, Fe+++, Mn++, Cu++, Al+++, Ca++, K++, Na+, PO4--- and SO3--- on the production and length of rhizomorphs of Armillaria borealis, A. gallica and A. ostoyae was studied. In pure medium, T. harzianum exhibited stimulating effect on rhizomorphs of A. borealis (both number and length and A. ostoyae (only initiation. Cu++ salt totaly inhibited the initiation of rhizomorphs of Armillaria borealis, A. gallica and A. ostoyae. Effect of other compounds on the activity of T. harzianum depended on Armillaria species. The majority of chemical compounds tested supressed the activity of non-volatile metabolites of T. harzianum. Evident stimulating effect was observed under influence of sulphate salts consisting Al++ and Fe+++ on the rhizomorph number of A. borealis and A. gallica, respectively.

Optical Modeling of Sea Salt Aerosols: The Effects of Nonsphericity and Inhomogeneity

Science.gov (United States)

Bi, Lei; Lin, Wushao; Wang, Zheng; Tang, Xiaoyun; Zhang, Xiaoyu; Yi, Bingqi

2018-01-01

The nonsphericity and inhomogeneity of marine aerosols (sea salts) have not been addressed in pertinent radiative transfer calculations and remote sensing studies. This study investigates the optical properties of nonspherical and inhomogeneous sea salts using invariant imbedding T-matrix simulations. Dry sea salt aerosols are modeled based on superellipsoidal geometries with a prescribed aspect ratio and roundness parameter. Wet sea salt particles are modeled as coated superellipsoids, as spherical particles with a superellipsoidal core, and as homogeneous spheres depending on the level of relative humidity. Aspect ratio and roundness parameters are found to be critical to interpreting the linear depolarization ratios (LDRs) of NaCl crystals from laboratory measurements. The optimal morphology parameters of NaCl necessary to reproduce the measurements are found to be consistent with data gleaned from an electron micrograph. The LDRs of wet sea salts are computed based on inhomogeneous models and compared with the measured data from ground-based LiDAR. The dependence of the LDR on relative humidity is explicitly considered. The increase in the LDR with relative humidity at the initial phase of deliquescence is attributed to both the size increase and the inhomogeneity effect. For large humidity values, the LDR substantially decreases because the overall particle shape becomes more spherical and the inhomogeneity effect in a particle on the LDR is suppressed for submicron sea salts. However, the effect of inhomogeneity on optical properties is pronounced for coarse-mode sea salts. These findings have important implications for atmospheric radiative transfer and remote sensing involving sea salt aerosols.

Seasonal variation of fractionated sea-salt particles on the Antarctic coast

Science.gov (United States)

Hara, K.; Osada, K.; Yabuki, M.; Yamanouchi, T.

2012-09-01

Aerosol sampling was conducted at Syowa Station, Antarctica (coastal station) in 2004-2006. SO42-depletion by mirabilite precipitation was identified from April through November. The fractionated sea-salt particles were distributed in ultrafine- coarse modes. Molar ratios of Mg2+/Na+ and K+/Na+ were higher than in bulk seawater ratio during winter-spring. The Mg2+/Na+ ratio in aerosols greatly exceeded the upper limit in the case only with mirabilite precipitation. The temperature dependence of Mg2+/Na+ ratio strongly suggested that higher ratios of Mg2+/Na+ and K+/Na+ were associated with sea-salt fractionation by precipitation of mirabilite at -9°C, hydrohalite at ca. -23°C and other salts such as ikaite at ca. -5°C and gypsum at ca. -22°C during winter-spring. Mg-salts with lower deliquescence relative humidity can be enriched gradually in the fractionated sea-salt particles. Results suggests that sea-salt fractionation can alter aerosol hygroscopicity and atmospheric chemistry in polar regions.

Sulphur isotope measurements on sulphates from Antarctic atmospheric precipitations, lake waters and salt efflorescences: a contribution to the study of the natural sulphur cycle

International Nuclear Information System (INIS)

Wand, U.; Maass, I.; Haendel, D.

1987-01-01

Sulphur isotope analyses are an important tool for the study of the natural sulphur cycle. However, on the northern hemisphere such studies particularly of the atmospheric component of the cycle are seriously hampered and in many regions practically impossible because of the high emission rate of anthropogenic sulphur. Only in remote areas of the world such as the Antarctic 34 S analyses can be used with success to identify the various natural sulphur sources (marine, biogenic and volcanic sources). We report here preliminary results of 34 S isotope measurements on sulphates from recent atmospheric precipitations (snow), lake waters and salt efflorescences sampled in the Schirmacher Oasis and the Wohlthat Massif, central Queen Maud Land, East Antarctica. Except for 4 efflorescence samples the sulphates investigated in this work are enriched in 34 S relative to the meteoritic sulphur standard (CDT). On an average the sulphates of our study area are isotopically lighter than those from the McMurdo region, South Victoria land. The latter region is characterized by the predominance of salts of marine origin. (author)

Determination of the environmental effect for the sea salt aerosols corrosion (3)

International Nuclear Information System (INIS)

Nakayasu, Fumio; Umehara, Toshihiro; Kato, Akitoshi; Taniguchi, Akihide

2009-01-01

Fukui Prefecture presently hosts 15 reactor units, including PWRs, BWR, FBR (Monjyu) and Japanese ATR (Fugen), all of which are located along the Japan Sea. Under such a circumstange, corrosion due to sea salt aerosols is one of the major factors causing ageing degradation of nuclear power plants facilities. Many scientists have been engaged in research on the corrosion of structures due to sea salt aerosols. In pursuing sea salt aerosol-induced corrosion research, it was necessary to perform corrosion tests under a certain set of environmental conditions since corrosion of structures is highly sensitive to environmental factors. In this respect, we installed the outdoor exposure test facilities along the sea coast in Awara-city and inland in Fukui-city, Fukui Prefecture of Japan. The amounts of sea salt aerosol tend to be lower in the summer season and higher in the winter season. The difference between seasons is expected to relate to the wind speed, the sunshine time, the rain amount and others. We tried to use the multivariate analysis for finding some relations between sea salt aerosol amounts and environment factor. We found the clear relations. (author)

Constraining Aerosol Optical Models Using Ground-Based, Collocated Particle Size and Mass Measurements in Variable Air Mass Regimes During the 7-SEAS/Dongsha Experiment

Science.gov (United States)

Bell, Shaun W.; Hansell, Richard A.; Chow, Judith C.; Tsay, Si-Chee; Wang, Sheng-Hsiang; Ji, Qiang; Li, Can; Watson, John G.; Khlystov, Andrey

2012-01-01

During the spring of 2010, NASA Goddard's COMMIT ground-based mobile laboratory was stationed on Dongsha Island off the southwest coast of Taiwan, in preparation for the upcoming 2012 7-SEAS field campaign. The measurement period offered a unique opportunity for conducting detailed investigations of the optical properties of aerosols associated with different air mass regimes including background maritime and those contaminated by anthropogenic air pollution and mineral dust. What appears to be the first time for this region, a shortwave optical closure experiment for both scattering and absorption was attempted over a 12-day period during which aerosols exhibited the most change. Constraints to the optical model included combined SMPS and APS number concentration data for a continuum of fine and coarse-mode particle sizes up to PM2.5. We also take advantage of an IMPROVE chemical sampler to help constrain aerosol composition and mass partitioning of key elemental species including sea-salt, particulate organic matter, soil, non sea-salt sulphate, nitrate, and elemental carbon. Our results demonstrate that the observed aerosol scattering and absorption for these diverse air masses are reasonably captured by the model, where peak aerosol events and transitions between key aerosols types are evident. Signatures of heavy polluted aerosol composed mostly of ammonium and non sea-salt sulphate mixed with some dust with transitions to background sea-salt conditions are apparent in the absorption data, which is particularly reassuring owing to the large variability in the imaginary component of the refractive indices. Extinctive features at significantly smaller time scales than the one-day sample period of IMPROVE are more difficult to reproduce, as this requires further knowledge concerning the source apportionment of major chemical components in the model. Consistency between the measured and modeled optical parameters serves as an important link for advancing remote

The origin of sea salt in snow on Arctic sea ice and in coastal regions

Directory of Open Access Journals (Sweden)

F. Domine

2004-01-01

Full Text Available Snow, through its trace constituents, can have a major impact on lower tropospheric chemistry, as evidenced by ozone depletion events (ODEs in oceanic polar areas. These ODEs are caused by the chemistry of bromine compounds that originate from sea salt bromide. Bromide may be supplied to the snow surface by upward migration from sea ice, by frost flowers being wind-blown to the snow surface, or by wind-transported aerosol generated by sea spray. We investigate here the relative importance of these processes by analyzing ions in snow near Alert and Ny-Ålesund (Canadian and European high Arctic in winter and spring. Vertical ionic profiles in the snowpack on sea ice are measured to test upward migration of sea salt ions and to seek evidence for ion fractionation processes. Time series of the ionic composition of surface snow layers are investigated to quantify wind-transported ions. Upward migration of unfractionated sea salt to heights of at least 17cm was observed in winter snow, leading to Cl- concentration of several hundred µM. Upward migration thus has the potential to supply ions to surface snow layers. Time series show that wind can deposit aerosols to the top few cm of the snow, leading also to Cl- concentrations of several hundred µM, so that both diffusion from sea ice and wind transport can significantly contribute ions to snow. At Ny-Ålesund, sea salt transported by wind was unfractionated, implying that it comes from sea spray rather than frost flowers. Estimations based on our results suggest that the marine snowpack contains about 10 times more Na+ than the frost flowers, so that both the marine snowpack and frost flowers need to be considered as sea salt sources. Our data suggest that ozone depletion chemistry can significantly enhance the Br- content of snow. We speculate that this can also take place in coastal regions and contribute to propagate ODEs inland. Finally, we stress the need to measure snow physical parameters

Stratigraphic response of salt marshes to slow rates of sea-level change

Science.gov (United States)

Daly, J.; Bell, T.

2006-12-01

Conventional models of salt-marsh development show an idealized spatial relationship between salt-marsh floral and foraminiferal zones, where the landward margin of the marsh gradually migrates inland in response to sea-level rise. This model predicts that transgression will result in persistent and possibly expanded salt marshes at the surface, depending on a variety of factors including sediment supply, hydrologic conditions, tidal range, and rate of sea-level rise. However, in areas with abundant sediment supply and slow rates of sea- level rise, the extent of back-barrier salt marshes may decline over time as the barrier-spits mature. Sea level around the northeast coast of Newfoundland is rising at a very slow rate during the late Holocene (flora. These transitions are interpreted to reflect the progradation of the spit, decreased tidal exchange in the back-barrier, and increased influence of freshwater streams discharging into the back-barrier setting. Decreased marine influence on the back-barrier environment leads to a floral and faunal shift associated with a regressive stratigraphy in an area experiencing sea-level rise. For studies of Holocene sea-level change requiring salt-marsh stratigraphic records, it is necessary to account for changing micro-environments to locate sites appropriate for study; salt marshes may play an important role in defining the record, but may not exist at the surface to guide investigation.

Potential sea salt aerosol sources from frost flowers in the pan-Arctic region

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; Russell, Lynn M. [Scripps Institution of Oceanography, University of California, San Diego, La Jolla California USA; Burrows, Susannah M. [Atmospheric Science and Global Change Division, Pacific Northwest National Laboratory, Richland Washington USA

2016-09-23

In order to better represent observed wintertime aerosol concentrations at Barrow, Alaska, we implemented an observationally-based parameterization for estimating sea salt production from frost flowers in the Community Earth System Model (CESM). In this work, we evaluate the potential influence of this sea salt source on the pan-Arctic (60ºN-90ºN) climate. Results show that frost flower salt emissions substantially increase the modeled surface sea salt aerosol concentration in the winter months when new sea ice and frost flowers are present. The parameterization reproduces both the magnitude and seasonal variation of the observed submicron sea salt aerosol concentration at surface in Barrow during winter much better than the standard CESM simulation without a frost-flower salt particle source. Adding these frost flower salt particle emissions increases aerosol optical depth by 10% and results in a small cooling at surface. The increase in salt particle mass concentrations of a factor of 8 provides nearly two times the cloud condensation nuclei concentration, as well as 10% increases in cloud droplet number and 40% increases in liquid water content near coastal regions adjacent to continents. These cloud changes reduce longwave cloud forcing by 3% and cause a small surface warming, increasing the downward longwave flux at the surface by 2 W m-2 in the pan-Arctic under the present-day climate.

Sea salt and pollution inputs over the continental United States

International Nuclear Information System (INIS)

Li, Y.-H.

1992-01-01

The average deposition rate of sea salt chloride over the world continents is about 10 meq m -2 yr -1 . Only about 14±1% of chloride in the pollution-corrected world average river is contributed by sea salt aerosols and the rest from the dissolution of evaporites. The significant increase of the ion concentrations in the Mississippi river from the year 1905 to 1987 was caused by anthropogenic inputs such as fossil fuel burning, common salt consumption, and dissolution of carbonate and silicate rocks by acids derived from acid precipitation. 29 refs., 4 figs., 3 tabs

Stimulation of sulfate-reducing activity at salt-saturation in the salterns of Ribandar, Goa, India

Digital Repository Service at National Institute of Oceanography (India)

Kerkar, S.; LokaBharathi, P.A.

salt pan. Each pans is surrounded by ?bandhs? or mud borders on all four sides to prevent siltation and help regulate the flow of water. In the Ribandar saltern, sea water from the Mandovi estuary enters the creek through a sluice gate at high tide... activity (SRA) in marine ecosystems, especially the coastal regions contributes as much as 50% organic carbon turnover (Jorgensen,1982). Sulphate accounts for 70 - 90% of total respiration in salt marsh sediments, where total sediment respiration rates...

Complete sulphate removal from neutralised acidic mine drainage with barium carbonate

CSIR Research Space (South Africa)

Swanepoel, H

2012-03-01

Full Text Available -barium-calcium) Desalination process which uses barium salts to further reduce the sulphate concentration to acceptable levels with the added advantage that sulphate removal can be controlled due to the low solubility of BaSO4. This paper reports on the results...

Determination of the environmental effect for the sea salt aerosols corrosion (2)

International Nuclear Information System (INIS)

Nakayasu, Fumio; Umehara, Toshihiro; Kato, Akitoshi; Taniguchi, Akihide

2008-01-01

Present all nuclear power plants in Fukui prefecture are located at the bay side of Japan Sea coast. New facilities may be planed to be at ocean side. The sea salt corrosion at the ocean side should be larger than it at the bay side. We have the salt damage experimental yard at Awara sea coast and at Fukui city (about 15km from coast) for the corrosion comparison study between Japan Sea coast and inland. We confirm the amounts of sea salt aerosol vary among the season and year. The weight loss of specimen inside of shelter without filter is higher than both of sheltered with filter and inland specimen. The weight loss of specimen inside of shelter with filter is almost same as it of inland specimen. We confirmed the filter which we used is sufficient capability to prevent corrosion. We confirmed the corrosion rate of both opened specimen and sheltered specimen without filter increased after some periods. (author)

Can salt marshes survive sea level rise ?

Science.gov (United States)

Tambroni, N.; Seminara, G.

2008-12-01

Stability of salt marshes is a very delicate issue depending on the subtle interplay among hydrodynamics, morphodynamics and ecology. In fact, the elevation of the marsh platform depends essentially on three effects: i) the production of soil associated with sediments resuspended by tidal currents and wind waves in the adjacent tidal flats, advected to the marsh and settling therein; ii) production of organic sediments by the salt marsh vegetation; iii) soil 'loss' driven by sea level rise and subsidence. In order to gain insight into the mechanics of the process, we consider a schematic configuration consisting of a salt marsh located at the landward end of a tidal channel connected at the upstream end with a tidal sea, under different scenarios of sea level rise. We extend the simple 1D model for the morphodynamic evolution of a tidal channel formulated by Lanzoni and Seminara (2002, Journal of Geophysical Research-Oceans, 107, C1) allowing for sediment resuspension in the channel and vegetation growth in the marsh using the depth dependent model of biomass productivity of Spartina proposed by Morris et al. (2002, Ecology, 83, pp. 2869 - 2877). We first focus on the case of a tide dominated salt marsh neglecting wind driven sediment resuspension in the shoal. Results show that the production of biomass plays a crucial role on salt marsh stability and, provided productivity is high enough, it may turn out to be sufficient to counteract the effects of sea level rise even in the absence of significant supply of mineral sediments. The additional effect of wind resuspension is then introduced. Note that the wind action is twofold: on one hand, it generates wind waves the amplitude of which is strongly dependent on shoal depth and wind fetch; on the other hand, it generates currents driven by the surface setup induced by the shear stress acting on the free surface. Here, each contribution is analysed separately. Results show that the values of bottom stress induced by

Weight-of-evidence approach in assessment of ecotoxicological risks of acid sulphate soils in the Baltic Sea river estuaries

Energy Technology Data Exchange (ETDEWEB)

Wallin, Jaana, E-mail: jaana.wallin@jyu.fi [Finnish Environment Institute SYKE, Survontie 9 A, FI-40500 Jyväskylä (Finland); Karjalainen, Anna K. [Finnish Environment Institute SYKE, Survontie 9 A, FI-40500 Jyväskylä (Finland); Schultz, Eija [Finnish Environment Institute SYKE, Hakuninmaantie 6, FI-00430 Helsinki (Finland); Järvistö, Johanna; Leppänen, Matti; Vuori, Kari-Matti [Finnish Environment Institute SYKE, Survontie 9 A, FI-40500 Jyväskylä (Finland)

2015-03-01

Acidity and leaching of metals from acid sulphate soils (ASSs) impair the water quality of receiving surface waters. The largest ASS areas in Europe are found in the coasts of the northern Baltic Sea. We used weight-of-evidence (WoE) approach to assess potential risks in 14 estuary sites affected by ASS in the Gulf of Finland, northern Baltic Sea. The assessment was based on exposure and effect profiles utilizing sediment and water metal concentrations and concurrent pH variation, sediment toxicity tests using the luminescent bacterium Vibrio fischeri and the midge Chironomus riparius, and the ecological status of benthic macroinvertebrate communities. Sediment metal concentrations were compared to national sediment quality criteria/guidelines, and water metal concentrations to environmental quality standards (EQSs). Hazard quotients (HQs) were established for maximum aluminium, cadmium and zinc concentrations at low pH based on applicable US EPA toxicity database. Sediment metal concentrations were clearly elevated in most of the studied estuaries. The EQS of cadmium (0.1 μg/l) was exceeded in 3 estuaries out of 14. The pH-minima were below the national threshold value (5.5) between good and satisfactory water quality in 10 estuaries. V. fischeri bioluminescence indicated toxicity of the sediments but toxic response was not observed in the C. riparius emergence test. Benthic invertebrate communities were deteriorated in 6 out of 14 sites based on the benthic invertebrate quality index. The overall ecotoxicological risk was assessed as low in five, moderate in three and high in five of the estuary sites. The risk assessment utilizing the WoE approach indicated that harmful effects of ASSs are likely to occur in the Baltic Sea river estuaries located at the ASS hotspot area. - Highlights: • Acid sulphate soils release high amounts of metals and acidity. • Metals and acidity are transported to estuary sites. • Acid sulphate soils impair the ecological status

The Dead Sea Mud and Salt: A Review of Its Characterization, Contaminants, and Beneficial Effects

Science.gov (United States)

Bawab, Abeer Al; Bozeya, Ayat; Abu-Mallouh, Saida; Abu Irmaileh, Basha'er; Daqour, Ismail; Abu-Zurayk, Rund A.

2018-02-01

The Dead Sea has been known for its therapeutic and cosmetic properties. The unique climatic conditions in the Dead Sea area make it a renowned site worldwide for the field of climatotherapy, which is a natural approach for the provision of medications for many human diseases including unusual exclusive salt composition of the water, a special natural mud, thermal mineral springs, solar irradiation, oxygen-rich and bromine-rich haze. This review focuses on the physical, chemical, and biological characteristics of the Dead Sea mud and salts, in addition to their contaminants, allowing this review to serve as a guide to interested researchers to their risks and the importance of treatment. Beneficial effects of Dead Sea mud and salts are discussed in terms of therapy and cosmetics. Additional benefits of both Dead Sea mud and salts are also discussed, such as antimicrobial action of the mud in relation to its therapeutic properties, and the potency of mud and salts to be a good medium for the growth of a halophilic unicellular algae, used for the commercial production of β-carotene Dunaliella.

Feasibility of laser-induced breakdown spectroscopy (LIBS) for classification of sea salts.

Science.gov (United States)

Tan, Man Minh; Cui, Sheng; Yoo, Jonghyun; Han, Song-Hee; Ham, Kyung-Sik; Nam, Sang-Ho; Lee, Yonghoon

2012-03-01

We have investigated the feasibility of laser-induced breakdown spectroscopy (LIBS) as a fast, reliable classification tool for sea salts. For 11 kinds of sea salts, potassium (K), magnesium (Mg), calcium (Ca), and aluminum (Al), concentrations were measured by inductively coupled plasma-atomic emission spectroscopy (ICP-AES), and the LIBS spectra were recorded in the narrow wavelength region between 760 and 800 nm where K (I), Mg (I), Ca (II), Al (I), and cyanide (CN) band emissions are observed. The ICP-AES measurements revealed that the K, Mg, Ca, and Al concentrations varied significantly with the provenance of each salt. The relative intensities of the K (I), Mg (I), Ca (II), and Al (I) peaks observed in the LIBS spectra are consistent with the results using ICP-AES. The principal component analysis of the LIBS spectra provided the score plot with quite a high degree of clustering. This indicates that classification of sea salts by chemometric analysis of LIBS spectra is very promising. Classification models were developed by partial least squares discriminant analysis (PLS-DA) and evaluated. In addition, the Al (I) peaks enabled us to discriminate between different production methods of the salts. © 2012 Society for Applied Spectroscopy

The impact of sulphate and magnesium on chloride binding in Portland cement paste

Energy Technology Data Exchange (ETDEWEB)

De Weerdt, K., E-mail: klaartje.d.weerdt@ntnu.no [Department of Structural Engineering, Norwegian University of science and Technology, Trondheim (Norway); SINTEF Building and Infrastructure, Trondheim (Norway); Orsáková, D. [Department of Civil Engineering, Technical University of Brno, Brno (Czech Republic); Geiker, M.R. [Department of Structural Engineering, Norwegian University of science and Technology, Trondheim (Norway)

2014-11-15

The effect of magnesium and sulphate present in sea water on chloride binding in Portland cement paste was investigated. Ground well hydrated cement paste was exposed to MgCl{sub 2}, NaCl, NaCl + MgCl{sub 2}, MgSO{sub 4} + MgCl{sub 2} and artificial sea water solutions with a range of concentrations at 20 °C. Chloride binding isotherms are determined and pH of the solutions were measured. A selection of samples was examined by SEM-EDS to identify phase changes upon exposure. The experimental data were compared with calculations of a thermodynamic model. Chloride binding from sea water was similar to chloride binding for NaCl solutions. The magnesium content in the sea water lead to a slight decrease in pH, but this did not result in a notable increase in chloride binding. The sulphate present in sea water reduces both chloride binding in C–S–H and AFm phases, as the C–S–H incorporates more sulphates instead of chlorides, and part of the AFm phases converts to ettringite.

Removal of radium from aqueous sulphate solutions

International Nuclear Information System (INIS)

Weir, D.R.; Masters, J.T.; Neven, M.

1983-01-01

Radium is often present in ores and an aqueous solution associated with the ore may consequently contain dissolved radium. It is frequently necessary to remove radium from such solutions to reduce the total radium content to a prescribed low level before the solution can be returned to the environment. The present invention is based on the discovery that the total radium content can be reduced to a satisfactory level within a reasonable time by adding a soluble barium salt to a radium-containing sulphate solution which also contains dissolved magnesium at a pH not greater than about 0 to precipitate radium as barium radium sulphate, raising the pH to at least 11 to precipitate an insoluble magnesium compound which collects the barium radium sulphate precipitate, and separating substantially all of the precipitates from the solution

On the evaluation of global sea-salt aerosol models at coastal/orographic sites

Science.gov (United States)

Spada, M.; Jorba, O.; Pérez García-Pando, C.; Janjic, Z.; Baldasano, J. M.

2015-01-01

Sea-salt aerosol global models are typically evaluated against concentration observations at coastal stations that are unaffected by local surf conditions and thus considered representative of open ocean conditions. Despite recent improvements in sea-salt source functions, studies still show significant model errors in specific regions. Using a multiscale model, we investigated the effect of high model resolution (0.1° × 0.1° vs. 1° × 1.4°) upon sea-salt patterns in four stations from the University of Miami Network: Baring Head, Chatam Island, and Invercargill in New Zealand, and Marion Island in the sub-antarctic Indian Ocean. Normalized biases improved from +63.7% to +3.3% and correlation increased from 0.52 to 0.84. The representation of sea/land interfaces, mesoscale circulations, and precipitation with the higher resolution model played a major role in the simulation of annual concentration trends. Our results recommend caution when comparing or constraining global models using surface concentration observations from coastal stations.

Nuclear risk reduction study. The study of structure corrosion caused by sea salt aerosols

International Nuclear Information System (INIS)

Nakayasu, Fumio

2008-01-01

Present all nuclear power plants in Fukui prefecture are located at the bay side of Japan Sea coast. New facilities may be planed to be at ocean side. The sea salt corrosion at the ocean side should be larger than it at the bay side. We have the salt damage experimental yard at Awara sea coast and at Fukui city (about 15km from coast) for the corrosion comparison study between Japan Sea coast and inland. We confirm the amounts of sea salt aerosol vary among the season and year. The weight loss of specimen inside of shelter without filter is higher than both of sheltered with filter and inland specimen. The weight loss of specimen inside of shelter with filter is almost same as it of inland specimen. We confirmed the filter which we used is sufficient capability to prevent corrosion. We confirmed the corrosion rate of both opened specimen and sheltered specimen without filter increased after some periods. (author)

Removal heavy metals and sulphate from waste waters by sulphate-reducing bacteria

Directory of Open Access Journals (Sweden)

Kušnierová Mária

2000-09-01

Full Text Available This article is devoted to the process of bacterial sulphate reduction, which is used to removal of heavy metals and sulphate ions from waste waters.The life of animals and plants depends on the existence of microscopic organisms – microorganisms (MO, which play an important role in cycle changes of biogenic elements on the earth. The sulphur cycle in the nature is considered as one of the oldest and most significant biological systems (Fig. 1. The sulphate-reducing bacteria (SRB miss the assimilatory part of the cycle and produce sulphides. The microbial population of this dissimilatory part is called “sulfuretum”. The SRB can be found in anaerobic mud and sediments of freshwater, thermal or non-thermal sulphur springs, mining waters from sulphide deposits, oil deposits, sea and ocean beds, and in the gastrointestinal tract of man and animals. The SRB represent a group of chemoorganotrophic, strictly anaerobic and gramnegative bacteria, which exhibit a great morphological and physiological diversity. Despite of their considerable morphological variety, they have one property in common, which is the ability to utilise preferentially sulphates (occasionally sulphites, thiosulphates, tetrathionates as electron acceptors, which are reduced to sulphides, during anaerobic respiration. The electron donors in these processes are simple organic compounds as lactate, malate, etc.,(heterotrophically reduction or gaseous hydrogen (autotrophically reduction. SRB can produce a considerable amount of hydrogen sulphide, which reacts easily in aqueous solution with the cations of heavy metals, forming metal sulphides that have low solubility. The bacterial sulphate reduction can be used for the treatment of acid mine drainage waters, which is considered to be the major problem associated with mining activities.In order to remove heavy metals from waste waters, e.g., from galvanizing plants, mine waters (Smolnik, Šobov locality and metallurgic plants (works

Deep Biosphere Secrets of the Mediterranean Salt Giant

Science.gov (United States)

Aloisi, Giovanni; Lugli, Stefano; McGenity, Terry; Kuroda, Junichiro; Takai, Ken; Treude, Tina; Camerlenghi, Angelo

2015-04-01

One component of the IODP multi-platform drilling proposal called DREAM (Deep-Sea Record of Mediterranean Messisnian Events), plans to investigate the deep biosphere associated to the Messinian Salinity Crisis (MSC) Salt Giant. We propose that the MSC Salt Giant, because of the variety of chemical environments it produces, has the potential to harbour an unprecedented diversity of microbial life with exceptional metabolic activity. Gypsum and anhydrite deposits provide a virtually unlimited source of sulphate at depths where oxidants are a rarity in other sedimentary environments. When reduced organic carbon comes into contact with these minerals there is the potential for a dynamic deep biosphere community of sulphate reducers to develop, with implications for sedimentary biogeochemical cycles and the souring of cruide oil. But the thickness of the Messinian evaporites and the range of chemical environments it harbours poses fundamental questions: will the interaction of several extreme conditions of temperature, salinity, pressure and chemical composition limit the ability of microbes to take advantage of such favourable thermodynamic conditions? And has such a diverse set of physical and chemical environments fostered microbal diversity, rather than phylogenetic specialization, as recent research into deep Mediterranean brine systems seems to indicate ? Over three kilometres in thickness, approaching the known temperature limits of life and with fluids precipitating carbonate, sulphate, halite and potash salts, microbes living within and around the MSC Salt Giant will be subject to the most exotic combinations of extremes, and have likely evolved yet unknown adaptations. Gypsum and Halite crystals contain fluid inclusions that are a micro-habitat in which microbes survive for tens of thousands, to possibly millions, of years, posing the fundamental question of cells devoting nearly all of their energy flow to somatic maintenance needs, rather than growth and

Sensitivity to deliberate sea salt seeding of marine clouds - observations and model simulations

OpenAIRE

Alterskjaer, K.; Kristjansson, J. E.; Seland, O.

2012-01-01

Sea salt seeding of marine clouds to increase their albedo is a proposed technique to counteract or slow global warming. In this study, we first investigate the susceptibility of marine clouds to sea salt injections, using observational data of cloud droplet number concentration, cloud optical depth, and liquid cloud fraction from the MODIS (Moderate Resolution Imaging Spectroradiometer) instruments on board the Aqua and Terra satellites. We then compare the derived susceptibility function to...

Climatic responses to the shortwave and longwave direct radiative effects of sea salt aerosol in present day and the last glacial maximum

Energy Technology Data Exchange (ETDEWEB)

Yue, Xu [Chinese Academy of Sciences (CAS), Climate Change Research Center (CCRC), Beijing (China); Chinese Academy of Sciences (CAS), Nansen-Zhu International Research Center, Institute of Atmospheric Physics (IAP), Beijing (China); Harvard University, School of Engineering and Applied Sciences, Cambridge, MA (United States); Liao, Hong [Chinese Academy of Sciences (CAS), State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC), Institute of Atmospheric Physics (IAP), P.O. Box 9804, Beijing (China)

2012-12-15

We examine the climatic responses to the shortwave (SW) and longwave (LW) direct radiative effects (RE) of sea salt aerosol in present day and the last glacial maximum (LGM) using a general circulation model with online simulation of sea salt cycle. The 30-year control simulation predicts a present-day annual emission of sea salt of 4,253 Tg and a global burden of 8.1 Tg for the particles with dry radii smaller than 10 {mu}m. Predicted annual and global mean SW and LW REs of sea salt are, respectively, -1.06 and +0.14 W m{sup -2} at the top of atmosphere (TOA), and -1.10 and +0.54 W m{sup -2} at the surface. The LW warming of sea salt is found to decrease with altitude, which leads to a stronger net sea salt cooling in the upper troposphere. The changes in global mean air temperature by the present-day sea salt are simulated to be -0.55, -0.63, -0.86, and -0.91 K at the surface, 850, 500a, and 200 hPa, respectively. The emission of sea salt at the LGM is estimated to be 4,075 Tg year{sup -1}. Relative to present day, the LGM sea salt emission is higher by about 18% over the tropical and subtropical oceans, and is lower by about 35% in the mid- and high-latitudes in both hemispheres because of the expansion of sea ice. As a result of the weakened LGM water cycle, the LGM annual and global mean burden of sea salt is predicted to be higher by 4% as compared to the present-day value. Compared with the climatic effect of sea salt in present day, the sea-salt-induced reductions in surface air temperature at the LGM have similar magnitude in the tropics but are weakened by about 0.18 and 0.14 K in the high latitudes of the Southern and Northern Hemispheres, respectively. We also perform a sensitivity study to explore the upper limit of the climatic effect of the LGM sea salt. We assume an across-the-board 30% increase in the glacial wind speed and consider sea salt emissions over sea ice, so that the model can reproduce the ratio of sea salt deposition between the LGM and

SIZE DISTRIBUTION OF SEA-SALT EMISSIONS AS A FUNCTION OF RELATIVE HUMIDITY

Science.gov (United States)

This note presents a straightforward method to correct sea-salt-emission particle-size distributions according to local relative humidity. The proposed method covers a wide range of relative humidity (0.45 to 0.99) and its derivation incorporates recent laboratory results on sea-...

Atmospheric fate of oil matter adsorbed on sea salt particles under UV light

Science.gov (United States)

Vaitilingom, M.; Avij, P.; Huang, H.; Valsaraj, K. T.

2014-12-01

The presence of liquid petroleum hydrocarbons at the sea water surface is an important source of marine pollution. An oil spill in sea-water will most likely occur due to an involuntary accident from tankers, offshore platforms, etc. However, a large amount of oil is also deliberately spilled in sea-water during the clean-out process of tank vessels (e.g. for the Mediterranean Sea, 490,000 tons/yr). Moreover, the pollution caused by an oil spill does not only affect the aquatic environment but also is of concern for the atmospheric environment. A portion of the oil matter present at the sea-water surface is transported into the atmosphere viaevaporation and adsorption at the surface of sea spray particles. Few studies are related to the presence of oil matter in airborne particles resulting from their adsorption on sea salt aerosols. We observed that the non-volatile oil matter was adsorbed at the surface of sea-salt crystals (av. size of 1.1 μm). Due to their small size, these particles can have a significant residence time in the atmosphere. The hydrocarbon matter adsorbed at the surface of these particles can also be transformed by catalyzers present in the atmosphere (i.e. UV, OH, O3, ...). In this work, we focused on the photo-oxidation rates of the C16 to C30alkanes present in these particles. We utilized a bubble column reactor, which produced an abundance of small sized bubbles. These bubbles generated droplets upon bursting at the air-salt water interface. These droplets were then further dried up and lifted to the top of the column where they were collected as particles. These particles were incubated in a controlled reactor in either dark conditions or under UV-visible light. The difference of alkane content analyzed by GC-MS between the particles exposed to UV or the particles not exposed to UV indicated that up to 20% in mass was lost after 20 min of light exposure. The degradation kinetics varied for each range of alkanes (C16-20, C21-25, C26

Simulating emission and chemical evolution of coarse sea-salt particles in the Community Multiscale Air Quality (CMAQ) model

OpenAIRE

J. T. Kelly; P. V. Bhave; C. G. Nolte; U. Shankar; K. M. Foley

2009-01-01

Chemical processing of sea-salt particles in coastal environments significantly impacts concentrations of particle components and gas-phase species and has implications for human exposure to particulate matter and nitrogen deposition to sensitive ecosystems. Emission of sea-salt particles from the coastal surf zone is known to be elevated compared to that from the open ocean. Despite the importance of sea-salt emissions and chemical processing, the US EPA's Community Multiscale Air Quality (C...

The microbial communities and potential greenhouse gas production in boreal acid sulphate, non-acid sulphate, and reedy sulphidic soils

Energy Technology Data Exchange (ETDEWEB)

Šimek, Miloslav, E-mail: misim@upb.cas.cz [Biology Centre AS CR, v. v. i., Institute of Soil Biology, 370 05 České Budějovice (Czech Republic); University of South Bohemia, Faculty of Science, 370 05 České Budějovice (Czech Republic); Virtanen, Seija; Simojoki, Asko [Department of Food and Environmental Sciences, University of Helsinki, FI-00014 Helsinki (Finland); Chroňáková, Alica; Elhottová, Dana; Krištůfek, Václav [Biology Centre AS CR, v. v. i., Institute of Soil Biology, 370 05 České Budějovice (Czech Republic); Yli-Halla, Markku [Department of Food and Environmental Sciences, University of Helsinki, FI-00014 Helsinki (Finland)

2014-01-01

Acid sulphate (AS) soils along the Baltic coasts contain significant amounts of organic carbon and nitrogen in their subsoils. The abundance, composition, and activity of microbial communities throughout the AS soil profile were analysed. The data from a drained AS soil were compared with those from a drained non-AS soil and a pristine wetland soil from the same region. Moreover, the potential production of methane, carbon dioxide, and nitrous oxide from the soils was determined under laboratory conditions. Direct microscopic counting, glucose-induced respiration (GIR), whole cell hybridisation, and extended phospholipid fatty acid (PLFA) analysis confirmed the presence of abundant microbial communities in the topsoil and also in the deepest Cg2 horizon of the AS soil. The patterns of microbial counts, biomass and activity in the profile of the AS soil and partly also in the non-AS soil therefore differed from the general tendency of gradual decreases in soil profiles. High respiration in the deepest Cg2 horizon of the AS soil (5.66 μg C g{sup − 1} h{sup − 1}, as compared to 2.71 μg C g{sup − 1} h{sup − 1} in a top Ap horizon) is unusual but reasonable given the large amount of organic carbon in this horizon. Nitrous oxide production peaked in the BCgc horizon of the AS and in the BC horizon of the non-AS soil, but the peak value was ten-fold higher in the AS soil than in the non-AS soil (82.3 vs. 8.6 ng N g{sup − 1}d{sup − 1}). The data suggest that boreal AS soils on the Baltic coast contain high microbial abundance and activity. This, together with the abundant carbon and total and mineral nitrogen in the deep layers of AS soils, may result in substantial gas production. Consequently, high GHG emissions could occur, for example, when the generally high water table is lowered because of arable farming. - Highlights: •Boreal acid sulphate soils contain large amounts of organic C and N in subsoils. •Microbial communities throughout the acid

The effect of sea ice loss on sea salt aerosol concentrations and the radiative balance in the Arctic

Directory of Open Access Journals (Sweden)

H. Struthers

2011-04-01

Full Text Available Understanding Arctic climate change requires knowledge of both the external and the local drivers of Arctic climate as well as local feedbacks within the system. An Arctic feedback mechanism relating changes in sea ice extent to an alteration of the emission of sea salt aerosol and the consequent change in radiative balance is examined. A set of idealized climate model simulations were performed to quantify the radiative effects of changes in sea salt aerosol emissions induced by prescribed changes in sea ice extent. The model was forced using sea ice concentrations consistent with present day conditions and projections of sea ice extent for 2100. Sea salt aerosol emissions increase in response to a decrease in sea ice, the model results showing an annual average increase in number emission over the polar cap (70–90° N of 86 × 10⁶ m⁻² s⁻¹ (mass emission increase of 23 μg m⁻² s⁻¹. This in turn leads to an increase in the natural aerosol optical depth of approximately 23%. In response to changes in aerosol optical depth, the natural component of the aerosol direct forcing over the Arctic polar cap is estimated to be between −0.2 and −0.4 W m⁻² for the summer months, which results in a negative feedback on the system. The model predicts that the change in first indirect aerosol effect (cloud albedo effect is approximately a factor of ten greater than the change in direct aerosol forcing although this result is highly uncertain due to the crude representation of Arctic clouds and aerosol-cloud interactions in the model. This study shows that both the natural aerosol direct and first indirect effects are strongly dependent on the surface albedo, highlighting the strong coupling between sea ice, aerosols, Arctic clouds and their radiative effects.

Effect of sea salt irrigation on plant growth, yield potential and some biochemical attributes of carissa carandas

International Nuclear Information System (INIS)

Tayyab, A.

2016-01-01

Carissa carandas (varn. Karonda) is an edible and medicinal plant having ability to grow in saline and water deficit conditions, however, little is known about its salinity tolerance. Therefore, the effect of salinity on vegetative (height and volume), reproductive (number of flowers and number, size and weight of fruits) and some biochemical parameters (leaf pigments, ions, soluble sugars, proteins, and phenols) of C. carandas were studied. Plants were grown in drum pot culture and irrigated with non-saline or saline water of 0.6% and 0.8% sea salt concentrations, for a period of 30 months. Results showed that, plant height, and canopy volume decreased with increasing salinity. The chlorophyll contents and chlorophyll a/b ratio followed the similar trend as for growth, however, carotenoids increased at 0.6% sea salt and subsequently decreased in higher salinity. Unchanged soluble sugar and protein content at 0.6% sea salt, as compared to control, could be attributed to leaf osmotic adjustments which decreased with further increase in salinity. Linear increase in soluble phenols and carotenoid/chlorophyll ratio indicating a protective strategy of C. carandas to minimize photo-damage. Besides increasing Na+ and decreasing K+ contents, plant seemed to maintain K+/Na+ ratio (above 1), especially at 0.6 sea salt, which disturbed at higher salinity. Salinity adversely affected reproductive growth of C. carandas where, production of flowers, and fruits were significantly reduced. In addition, fresh and dry weights of fruits decreased with increasing salinity, but salinity did not affect fruit length and diameter. Present study provides basic information related to plant growth, fruit yield and some biochemical attributes, which suggest that C. carandas is moderately salt tolerant plant. This plant showed potential to grow on saline marginal lands using brackish water irrigation and provide biomass for edible and medicinal purposes. However, in-depth analysis of field and

A century of climate variability in central Dronning Maud Land, East Antarctica, and its relation to Southern Annular Mode and El Nino-Southern Oscillation

Digital Repository Service at National Institute of Oceanography (India)

Naik, S.S.; Thamban, M.; Laluraj, C.M.; Redkar, B.L.; Chaturvedi, A.

the summer maxima in δ 18 O values; ii) nssSO 4 2- (non-sea salt sulphate) markers of volcanic eruptions; and iii) atomic bomb markers. The high sampling resolution ensured that each annual accumulation layer is represented on an average by thirteen δ 18...

Continuous 25-yr aerosol records at coastal Antarctica – I: inter-annual variability of ionic compounds and links to climate indices

OpenAIRE

Weller, Rolf; Wagenbach, Dietmar; Legrand, Michel; Elsässer, Christoph; Tian-Kunze, Xiangshan; König-Langlo, Gert

2011-01-01

The aerosol climatology at the coastal Antarctic Neumayer Station (NM) was investigated based on continuous, 25-yr long observations of biogenic sulphur components (methanesulfonate and non–sea salt sulphate), sea salt and nitrate. Although significant long-term trends could only be detected for nitrate (−3.6 ± 2.5% per year between 1983 and 1993 and +4.0 ± 3.2% per year from 1993–2007), non-harmonic periodicities between 2 and 5 yr were typical for all species. Dedicated time series analyses...

Effect of temperature on sulphate reduction, growth rate and growth yield in five psychrophilic sulphate-reducing bacteria from Arctic sediments

DEFF Research Database (Denmark)

Knoblauch, C.; Jørgensen, BB

1999-01-01

Five psychrophilic sulphate-reducing bacteria (strains ASv26, LSv21, PSv29, LSv54 and LSv514) isolated from Arctic sediments were examined for their adaptation to permanently low temperatures, All strains grew at -1.8 degrees C, the freezing point of sea water, but their optimum temperature...... and T(opt). For strains LSv21 and LSv514, however, growth yields were highest at the lowest temperatures, around 0 degrees C. The results indicate that psychrophilic sulphate-reducing bacteria are specially adapted to permanently low temperatures by high relative growth rates and high growth yields...... at in site conditions....

Evidence of Road Salt in New Hampshire’s Snowpack Hundreds of Meters from Roadways

Directory of Open Access Journals (Sweden)

James Lazarcik

2017-07-01

Full Text Available Salinization of surface and groundwater has been directly linked to the area of road surfaces in a watershed and the subsequent wintertime maintenance used to keep roads free of snow and ice. Most studies that explore road salt in snow along roadways limit the study to within 100 m from a roadway and conclude that there is negligible deposition of de-icing salt at distances greater than 100 m. In this study, we analyze the ion content of the southern New Hampshire snowpack and use Mg2+ as a conservative sea-salt tracer to calculate sea salt and non-sea salt fractions of Cl−. There is a minimum of 60% non-sea salt Cl−, which we attribute to road salt, in the snowpack at our study sites 115 to 350 m from the nearest maintained roadways. This suggests that larger areas need to be considered when investigating the negative impact of Cl− loading due to winter-time maintenance.

Determinants of magnesium sulphate use in women hospitalized at <29 weeks with severe or non-severe pre-eclampsia.

Directory of Open Access Journals (Sweden)

Dane A De Silva

Full Text Available Magnesium sulphate is recommended by international guidelines to prevent eclampsia among women with pre-eclampsia, especially when it is severe, but fewer than 70% of such women receive magnesium sulphate. We aimed to identify variables that prompt Canadian physicians to administer magnesium sulphate to women with pre-eclampsia.Data were used from the Canadian Perinatal Network (2005-11 of women hospitalized at <29 weeks' who were thought to be at high risk of delivery due to pre-eclampsia (using broad Canadian definition. Unadjusted analyses of relative risks were estimated directly and population attributable risk percent (PAR% calculated to identify variables associated with magnesium sulphate use. A multivariable model was created and a generalized estimating equation was used to estimate the adjusted RR that explained magnesium sulphate use in pre-eclampsia. The adjusted PAR% was estimated by bootstrapping.Of 631 women with pre-eclampsia, 174 (30.1% had severe pre-eclampsia, of whom 131 (75.3% received magnesium sulphate. 457 (69.9% women had non-severe pre-eclamspia, of whom 291 (63.7% received magnesium sulphate. Use of magnesium sulphate among women with pre-eclampsia could be attributed to the following clinical factors (PAR%: delivery for 'adverse conditions' (48.7%, severe hypertension (21.9%, receipt of antenatal corticosteroids (20.0%, maternal transport prior to delivery (9.9%, heavy proteinuria (7.8%, and interventionist care (3.4%.Clinicians are more likely to administer magnesium sulphate for eclampsia prophylaxis in the presence of more severe maternal clinical features, in addition to concomitant antenatal corticosteroid administration, and shorter admission to delivery periods related to transport from another institution or plans for interventionist care.

Crystallisation of mixtures of ammonium nitrate, ammonium sulphate and soot

NARCIS (Netherlands)

Dougle, P.G.; Veefkind, J.P.; Brink, H.M. ten

1998-01-01

Crystallisation of laboratory aerosols of ammonium nitrate and of internal mixtures of this salt with ammonium sulphate were investigated using humidity controlled nephelometry. The aerosol was produced via nebulizing of solutions and then dried to 25% RH, which is a realistic minimum value for

Sulphate solubility and sulphate diffusion in oxide glasses: implications for the containment of sulphate-bearing nuclear wastes

International Nuclear Information System (INIS)

Lenoir, M.

2009-09-01

The thesis deals with sulphate solubility and sulphate diffusion in oxide glasses, in order to control sulphate incorporation and sulphate volatilization in nuclear waste glasses. It was conducted on simplified compositions, in the SiO 2 -B 2 O 3 -R 2 O (R = Li, Na, K, Cs), SiO 2 -B 2 O 3 -BaO and V 2 O 5 -B 2 O 3 -BaO systems. These compositions allowed us to study the influence of the nature of network-modifying ions (Li + , Na + , K + , Cs + or Ba 2+ ) and also of former elements (Si, B, V), on structure and properties of glasses. Sulphate volatility is studied in sodium borosilicate melts using an innovative technique of sulphate quantitation with Raman spectroscopy. This technique is useful to obtain kinetic curves of sulphate volatilization. The establishment of a model to fit these curves leads to the determination of diffusion coefficients of sulphate. These diffusion coefficients can thus be compared to diffusion coefficients of other species, determined by other techniques and presented in the literature. They are also linked to diffusion coefficients in relation with the viscosity of the melts. Concerning sulphate solubility in glasses, it depends on glass composition and on the nature of sulphate incorporated. Sulphate incorporation in alkali borosilicate glasses leads to the formation of a sulphate layer floating on top of the melt. Sulphate incorporation in barium borosilicate and boro-vanadate glasses leads to the crystallization of sulphate species inside the vitreous matrix. Moreover, sulphate solubility is higher in these glasses than in alkali borosilicates. Finally, exchanges between cations present in glasses and cations present in the sulphate phase are also studied. (author)

Removal of sulphates from waste waters by sulphate-reducing bacteria

Directory of Open Access Journals (Sweden)

Luptáková Alena

2002-03-01

Full Text Available are present in almost all types of water, usually as a simple anion SO42-. The sulphates together with hydrogencarbonates and chlorides are principal anions in natural waters. In typical underground and surface waters, the concentration of sulphates is in the range from ten to hundreds milligrams per litre.Nowadays, the importance of the control of sulphate concentration in waste waters increases. According to the Slovak legislation the limit concentration of sulphates in surface and drinking waters is 250 mg.l-1 . In rivers the contents of sulphates increases mainly by the discharge of waste waters, which are coming mainly from chemical, textile, metallurgical, pharmaceutical, paper and mining industry. The concentration of sulphates in these waters is in the order of grams per litre.Many technologies for the sulphates removal from waste waters exist, including biologico-chemical processes. The principle of one of these methods is the reduction of sulphates by sulphate-reducing bacteria to hydrogen-sulphide.The objective of this work was to study the effect of initial sulphates concentration on the activity of anaerobic sulphate reducers as well as the kinetics of the anaerobic sulphate reduction. The batch reactor was used at temperature of 30°C and pH 7,5. Lactate was used as the carbon source.

Sulphate in Pregnancy

Directory of Open Access Journals (Sweden)

Paul A. Dawson

2015-03-01

Full Text Available Sulphate is an obligate nutrient for healthy growth and development. Sulphate conjugation (sulphonation of proteoglycans maintains the structure and function of tissues. Sulphonation also regulates the bioactivity of steroids, thyroid hormone, bile acids, catecholamines and cholecystokinin, and detoxifies certain xenobiotics and pharmacological drugs. In adults and children, sulphate is obtained from the diet and from the intracellular metabolism of sulphur-containing amino acids. Dietary sulphate intake can vary greatly and is dependent on the type of food consumed and source of drinking water. Once ingested, sulphate is absorbed into circulation where its level is maintained at approximately 300 μmol/L, making sulphate the fourth most abundant anion in plasma. In pregnant women, circulating sulphate concentrations increase by twofold with levels peaking in late gestation. This increased sulphataemia, which is mediated by up-regulation of sulphate reabsorption in the maternal kidneys, provides a reservoir of sulphate to meet the gestational needs of the developing foetus. The foetus has negligible capacity to generate sulphate and thereby, is completely reliant on sulphate supply from the maternal circulation. Maternal hyposulphataemia leads to foetal sulphate deficiency and late gestational foetal death in mice. In humans, reduced sulphonation capacity has been linked to skeletal dysplasias, ranging from the mildest form, multiple epiphyseal dysplasia, to achondrogenesis Type IB, which results in severe skeletal underdevelopment and death in utero or shortly after birth. Despite being essential for numerous cellular and metabolic functions, the nutrient sulphate is largely unappreciated in clinical settings. This article will review the physiological roles and regulation of sulphate during pregnancy, with a particular focus on animal models of disturbed sulphate homeostasis and links to human pathophysiology.

Revealing discriminating power of the elements in edible sea salts: Line-intensity correlation analysis from laser-induced plasma emission spectra

Energy Technology Data Exchange (ETDEWEB)

Lee, Yonghoon, E-mail: yhlee@mokpo.ac.kr [Department of Chemistry, Mokpo National University, Jeonnam 534-729 (Korea, Republic of); Ham, Kyung-Sik [Department of Food Engineering, Mokpo National University, Jeonnam 534-729 (Korea, Republic of); Han, Song-Hee [Division of Maritime Transportation System, Mokpo National Maritime University, Jeonnam 530-729 (Korea, Republic of); Yoo, Jonghyun, E-mail: jyoo@appliedspectra.com [Applied Spectra, Inc., 46665 Fremont Boulevard, Fremont, CA 94538 (United States); Jeong, Sungho [School of Mechatronics, Gwangju Institute of Science and Technology, Gwangju 500-712 (Korea, Republic of)

2014-11-01

We have investigated the discriminating power of the elements in edible sea salts using Laser-Induced Breakdown Spectroscopy (LIBS). For the ten different sea salts from South Korea, China, Japan, France, Mexico and New Zealand, LIBS spectra were recorded in the spectral range between 190 and 1040 nm, identifying the presence of Na, Cl, K, Ca, Mg, Li, Sr, Al, Si, Ti, Fe, C, O, N, and H. Intensity correlation analysis of the observed emission lines provided a valuable insight into the discriminating power of the different elements in the sea salts. The correlation analysis suggests that the elements with independent discrimination power can be categorized into three groups; those that represent dissolved ions in seawater (K, Li, and Mg), those that are associated with calcified particles (Ca and Sr), and those that are present in soils contained in the sea salts (Al, Si, Ti, and Fe). Classification models using a few emission lines selected based on the results from intensity correlation analysis and full broadband LIBS spectra were developed based on Principal Component Analysis (PCA) and Partial Least Squares-Discriminant Analysis (PLS-DA) and their performances were compared. Our results indicate that effective combination of a few emission lines can provide a dependable model for discriminating the edible sea salts and the performance is not much degraded from that based on the full broadband spectra. This can be rationalized by the intensity correlation results. - Highlights: • Broadband LIBS spectra of various edible sea salts were obtained. • Intensity correlation of emission lines of the elements in edible sea salts was analyzed. • The elements were categorized into three groups with independent discriminating power. • The effective combination of a few lines can provide dependable classification models.

Incorporation of layered double nanomaterials in thin film nanocomposite nanofiltration membrane for magnesium sulphate removal

Science.gov (United States)

Hanis Tajuddin, Muhammad; Yusof, Norhaniza; Salleh, Wan Norharyati Wan; Fauzi Ismail, Ahmad; Hanis Hayati Hairom, Nur; Misdan, Nurasyikin

2018-03-01

Thin film nanocomposite (TFN) membrane with copper-aluminium layered double hydroxides (LDH) incorporated into polyamide (PA) selective layer has been prepared for magnesium sulphate salt removal. 0, 0.05, 0.1, 0.15, 0.2 wt% of LDH were dispersed in the trimesoyl chloride (TMC) in n-hexane as organic solution and embedded into PA layer during interfacial polymerization with piperazine. The fabricated membranes were further characterized to evaluate its morphological structure and membrane surface hydrophilicity. The TFN membranes performance were evaluated with divalent salt magnesium sulphate (MgSO4) removal and compared with thin film composite (TFC). The morphological structures of TFN membranes were altered and the surface hydrophilicity were enhanced with addition of LDH. Incorporation of LDH has improved the permeate water flux by 82.5% compared to that of TFC membrane with satisfactory rejection of MgSO4. This study has experimentally validated the potential of LDH to improve the divalent salt separation performance for TFN membranes.

Incorporation of layered double nanomaterials in thin film nanocomposite nanofiltration membrane for magnesium sulphate removal

Directory of Open Access Journals (Sweden)

Tajuddin Muhammad Hanis

2018-01-01

Full Text Available Thin film nanocomposite (TFN membrane with copper-aluminium layered double hydroxides (LDH incorporated into polyamide (PA selective layer has been prepared for magnesium sulphate salt removal. 0, 0.05, 0.1, 0.15, 0.2 wt% of LDH were dispersed in the trimesoyl chloride (TMC in n-hexane as organic solution and embedded into PA layer during interfacial polymerization with piperazine. The fabricated membranes were further characterized to evaluate its morphological structure and membrane surface hydrophilicity. The TFN membranes performance were evaluated with divalent salt magnesium sulphate (MgSO4 removal and compared with thin film composite (TFC. The morphological structures of TFN membranes were altered and the surface hydrophilicity were enhanced with addition of LDH. Incorporation of LDH has improved the permeate water flux by 82.5% compared to that of TFC membrane with satisfactory rejection of MgSO4. This study has experimentally validated the potential of LDH to improve the divalent salt separation performance for TFN membranes.

Authigenic gypsum in a deep sea core from Southeastern Arabian Sea

Digital Repository Service at National Institute of Oceanography (India)

Guptha, M.V.S.

Authigenic gypsum has been encountered in a deep sea core RC9-157 from the southeastern Arabian Sea at a depth of 4111 m which is a zone of lysocline. The formation of gypsum in the deep sea region is attributed to the prevailing sulphate rich...

Changing Sediment Dynamics of a Mature Backbarrier Salt Marsh in Response to Sea-Level Rise and Storm Events

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Mark Schuerch

2018-05-01

Full Text Available Our study analyses the long-term development of a tidal backbarrier salt marsh in the northern German Wadden Sea. The focus lies on the development of the high-lying, inner, mature part of the salt marsh, which shows a striking history of changing sediment dynamics. The analysis of high-resolution old aerial photographs and sampled sediment cores suggests that the mature part of the marsh was shielded by a sand barrier from the open sea for decades. The supply with fine-grained sediments occurred from the marsh inlet through the tidal channels to the inner salt marsh. Radiometric dating (210Pb and 137Cs reveals that the sedimentation pattern changed fundamentally around the early-mid 1980s when the sedimentation rates increased sharply. By analyzing the photographic evidence, we found that the sand barrier was breached during storm events in the early 1980s. As a result, coarse-grained sediments were brought directly through this overwash from the sea to the mature part of the salt marsh and increased the sedimentation rates. We show that the overwash and the channels created by these storm events built a direct connection to the sea and reduced the distance to the sediment source which promoted salt marsh growth and a supply with coarse-grained sediments. Consequently, the original sediment input from the tidal channels is found to play a minor role in the years following the breach event. The presented study showcases the morphological development of a mature marsh, which contradicts the commonly accepted paradigm of decreasing sedimentation rates with increasing age of the marsh. We argue that similar trends are likely to be observed in other backbarrier marshes, developing in the shelter of unstabilized sand barriers. It further highlights the question of how resilient these salt marshes are toward sea level rise and how extreme storm events interfere in determining the resilience of a mature salt marsh.

Wind-Driven Sea-Level Variation Influences Dynamics of Salt Marsh Vegation

DEFF Research Database (Denmark)

Kim, Daehyun; Cairns, David; Bartholdy, Jesper

2011-01-01

Long-term variation of mean sea level has been considered the primary exogenous factor of vegetation dynamics in salt marshes. In this study, we address the importance of short-term, wind-induced rise of the sea surface in such biogeographic changes. There was an unusual opportunity for examining......, waterlogging of marsh soils, which has retarded ecological succession. To conclude, we stress the need for a multitemporal perspective that recognizes the significance of short-term sea-level fluctuations nested within long-term trends......) continuous sedimentation with spatial variability (2.0–4.0 mm yr-1), (3) increased frequency of over-marsh flooding events, and (4) contemporary dominance of Halimione portulacoides, indicating little progressive succession toward a later phase. Conventionally, recent eustatic sea-level rise was believed...... to drive the increased frequency of flooding and such retarded succession. Skallingen, however, has showed more or less equilibrated yearly rates between sea-level rise and surface accretion. This implies that the long-term, gradual sea-level rise alone might not be enough to explain the increased...

Will fluctuations in salt marsh-mangrove dominance alter vulnerability of a subtropical wetland to sea-level rise?

Science.gov (United States)

McKee, Karen L; Vervaeke, William C

2018-03-01

To avoid submergence during sea-level rise, coastal wetlands build soil surfaces vertically through accumulation of inorganic sediment and organic matter. At climatic boundaries where mangroves are expanding and replacing salt marsh, wetland capacity to respond to sea-level rise may change. To compare how well mangroves and salt marshes accommodate sea-level rise, we conducted a manipulative field experiment in a subtropical plant community in the subsiding Mississippi River Delta. Experimental plots were established in spatially equivalent positions along creek banks in monospecific stands of Spartina alterniflora (smooth cordgrass) or Avicennia germinans (black mangrove) and in mixed stands containing both species. To examine the effect of disturbance on elevation dynamics, vegetation in half of the plots was subjected to freezing (mangrove) or wrack burial (salt marsh), which caused shoot mortality. Vertical soil development was monitored for 6 years with the surface elevation table-marker horizon system. Comparison of land movement with relative sea-level rise showed that this plant community was experiencing an elevation deficit (i.e., sea level was rising faster than the wetland was building vertically) and was relying on elevation capital (i.e., relative position in the tidal frame) to survive. Although Avicennia plots had more elevation capital, suggesting longer survival, than Spartina or mixed plots, vegetation type had no effect on rates of accretion, vertical movement in root and sub-root zones, or net elevation change. Thus, these salt marsh and mangrove assemblages were accreting sediment and building vertically at equivalent rates. Small-scale disturbance of the plant canopy also had no effect on elevation trajectories-contrary to work in peat-forming wetlands showing elevation responses to changes in plant productivity. The findings indicate that in this deltaic setting with strong physical influences controlling elevation (sediment accretion

Continuous 25-yr aerosol records at coastal Antarctica - I: inter-annual variability of ionic compounds and links to climate indices

Energy Technology Data Exchange (ETDEWEB)

Weller, Rolf; Koenig-Langlo, Gert (Alfred Wegener Inst. for Polar and Marine Research, Bremerhaven (Germany)), e-mail: Rolf.Weller@awi.de; Wagenbach, Dietmar; Elsaesser, Christoph (Institut fur Umweltphysik, Univ. of Heidelberg, Heidelberg (Germany)); Legrand, Michel (Laboratoire de Glaciologie et Geophysique de l' Environnement du Centre National de la Recherche Scientifique, St Martin d' Heres (France)); Tian-Kunze, Xiangshan (Institut fur Meereskunde, Univ. of Hamburg, Hamburg (Germany))

2011-11-15

The aerosol climatology at the coastal Antarctic Neumayer Station (NM) was investigated based on continuous, 25-yr long observations of biogenic sulphur components (methanesulfonate and non-sea salt sulphate), sea salt and nitrate. Although significant long-term trends could only be detected for nitrate (-3.6 +- 2.5% per year between 1983 and 1993 and +4.0 +- 3.2% per year from 1993-2007), non-harmonic periodicities between 2 and 5 yr were typical for all species. Dedicated time series analyses revealed that relations to sea ice extent and various circulation indices are weak at best or not significant. In particular, no consistent link between sea ice extent and sea salt loadings was evident suggesting only a rather local relevance of the NM sea salt record. Nevertheless, a higher Southern Annular Mode index tended to entail a lower biogenic sulphur signal. In examining the spatial uniformity of the NM findings we contrasted them to respective 17 yr records from the coastal Dumont d'Urville Station. We found similar long-term trends for nitrate, indicating an Antarctic-wide but not identifiable atmospheric signal, although any significant impact of solar activity or pollution could be ruled out. No inter-site variability on the multiannual scale was evident for the other ionic compounds

Long-term changes in the water quality of rainfall, cloud water and stream water for moorland, forested and clear-felled catchments at Plynlimon, mid-Wales

Directory of Open Access Journals (Sweden)

C. Neal

2001-01-01

Full Text Available Long term changes in the water quality of rainfall, cloud water and stream waters draining acidic and acid sensitive moorland and forested catchments at Plynlimon, mid-Wales, are examined for the period 1983 to 2001. Atmospheric inputs of chloride and sulphate are influenced by the relative inputs of clean maritime and polluted land based air masses. There is no systematic increase or decrease over time for chloride and non-sea-salt sulphate. Rather, there is a decadal scale process possibly representative of the influence of the North Atlantic Oscillation that affects the maritime and pollution climate of the Atlantic seaboard of the UK. Over 17 years of study, there may be a small decrease in non-sea-salt sulphate of about 10 μeq l-1 and a small improvement in acid neutralising capacity of about 20 to 30 μeq l-1 in rainfall. There is a clear improvement in cloud water chemistry with respect to pollutant components (ammonium, nitrate, non-sea-salt sulphate and acidity (acid neutralising capacity improved by about 300 μeq l-1 through the study period. Many of the changes in cloud water chemistry are similar to rainfall over the same period except the magnitude of change is larger for the cloud water. Within the streams, there is some evidence for reductions in acidity as reflected by acid neutralising capacity becoming less negative. For one stream, deforestation occurred during the sampling period and this led to large increases in nitrate and smaller increases in aluminium midway through the study period. However, the climate and hydrological variability largely masked out other changes. The current analysis provides only a start to identifying trends for such a complex and variable environmental system. The need for strong statistical tools is emphasised to resolve issues of: (a hydrological induced water quality variability, (b changing soil and groundwater "endmember" chemistry contribution to the stream and (c the non-linear patterns of

Dendrochronology of Atriplex portulacoides and Artemisia maritima in Wadden Sea salt marshes

NARCIS (Netherlands)

Decuyper, M.; Slim, P.A.; Loon-Steensma, van J.M.

2014-01-01

The study uses a rather unusual method, dendrochronology, to investigate the growth and survival of Atriplex portulacoides L. and Artemisia maritima L. on salt marshes at two field sites on the Dutch North Sea barrier islands of Terschelling and Ameland. By providing information on longevity of

Environmental assessment of water-salt regime of irrigated soils in the Central-Chernozem Region of Russia

Science.gov (United States)

Alaeva, Liliia; Negrobova, Elena; Jablonskikh, Lidiia; Rumyantseva, Irina

2016-04-01

A large part of Central Chernozem Region is located in the zone of risky agriculture. This led to intensive use of soil in the irrigation system. Therefore, a detailed analysis of water-salt regime of irrigated soils required for ecological state assessment of soils for irrigation. In the investigated area the fone component of the soil cover on the levelled plateau are chernozems. On the slopes formed a meadow-chernozem soils. Parent material is a cover loess-like calcareous non-saline clay. In these soils, our studies found component-quantitative composition of the aqueous extract, the chemism of salinity, which allowed us to make conclusions about the direction of the salinisation process in soils when used in the system of irrigated agriculture. By quantity water extract chernozems are non-saline, the ratio of anions and cations are chloride-sulphate magnesium-calcium salinization. In the composition of easily soluble salts dominated by Ca(HCO3)2. On sum of toxic salts in the soils are non-saline. This type and chemism of salinity deep brackish groundwater (more than 5 m) can be actively used in the system of rational irrigation. The meadow-chernozem soils formed under conditions of increased surface and soil moisture in the shallow brackish water at a depth of 3-5 m. These soils by quantity water extract are non-saline, anionic-cationic ratio - chloride-sulphate magnesium-calcium salinization. Permanent components of salt associations are Ca(HCO3)2, MgCl2, Na2SO4. On sum of toxic salts in the soil is not saline throughout the profile. The chemism of salinity and the proximity of groundwater at irregular watering can lead to the rise of groundwater level, the development of gleyed and sodium alkalinization. Thus, the introduction of intensive irrigated agriculture on chernozems and hydromorphic analogues may lead to the development in them of negative consequences. The most dynamic indicator is the water-salt regime, the systematic monitoring and control which

Individual aerosol particles in and below clouds along a Mt. Fuji slope: Modification of sea-salt-containing particles by in-cloud processing

Science.gov (United States)

Ueda, S.; Hirose, Y.; Miura, K.; Okochi, H.

2014-02-01

Sizes and compositions of atmospheric aerosol particles can be altered by in-cloud processing by absorption/adsorption of gaseous and particulate materials and drying of aerosol particles that were formerly activated as cloud condensation nuclei. To elucidate differences of aerosol particles before and after in-cloud processing, aerosols were observed along a slope of Mt. Fuji, Japan (3776 m a.s.l.) during the summer in 2011 and 2012 using a portable laser particle counter (LPC) and an aerosol sampler. Aerosol samples for analyses of elemental compositions were obtained using a cascade impactor at top-of-cloud, in-cloud, and below-cloud altitudes. To investigate composition changes via in-cloud processing, individual particles (0.5-2 μm diameter) of samples from five cases (days) collected at different altitudes under similar backward air mass trajectory conditions were analyzed using a transmission electron microscope (TEM) equipped with an energy dispersive X-ray analyzer. For most cases (four cases), most particles at all altitudes mainly comprised sea salts: mainly Na with some S and/or Cl. Of those, in two cases, sea-salt-containing particles with Cl were found in below-cloud samples, although sea-salt-containing particles in top-of-cloud samples did not contain Cl. This result suggests that Cl in the sea salt was displaced by other cloud components. In the other two cases, sea-salt-containing particles on samples at all altitudes were without Cl. However, molar ratios of S to Na (S/Na) of the sea-salt-containing particles of top-of-cloud samples were higher than those of below-cloud samples, suggesting that sulfuric acid or sulfate was added to sea-salt-containing particles after complete displacement of Cl by absorption of SO2 or coagulation with sulfate. The additional volume of sulfuric acid in clouds for the two cases was estimated using the observed S/Na values of sea-salt-containing particles. The estimation revealed that size changes by in

Effects of sea-level rise on salt water intrusion near a coastal well field in southeastern Florida

Science.gov (United States)

Langevin, Christian D.; Zygnerski, Michael

2013-01-01

A variable-density groundwater flow and dispersive solute transport model was developed for the shallow coastal aquifer system near a municipal supply well field in southeastern Florida. The model was calibrated for a 105-year period (1900 to 2005). An analysis with the model suggests that well-field withdrawals were the dominant cause of salt water intrusion near the well field, and that historical sea-level rise, which is similar to lower-bound projections of future sea-level rise, exacerbated the extent of salt water intrusion. Average 2005 hydrologic conditions were used for 100-year sensitivity simulations aimed at quantifying the effect of projected rises in sea level on fresh coastal groundwater resources near the well field. Use of average 2005 hydrologic conditions and a constant sea level result in total dissolved solids (TDS) concentration of the well field exceeding drinking water standards after 70 years. When sea-level rise is included in the simulations, drinking water standards are exceeded 10 to 21 years earlier, depending on the specified rate of sea-level rise.

Continuous Flow Hygroscopicity-Resolved Relaxed Eddy Accumulation (Hy-Res REA) Method of Measuring Size-Resolved Sea-Salt Particle Fluxes

Science.gov (United States)

Meskhidze, N.; Royalty, T. M.; Phillips, B.; Dawson, K. W.; Petters, M. D.; Reed, R.; Weinstein, J.; Hook, D.; Wiener, R.

2017-12-01

The accurate representation of aerosols in climate models requires direct ambient measurement of the size- and composition-dependent particle production fluxes. Here we present the design, testing, and analysis of data collected through the first instrument capable of measuring hygroscopicity-based, size-resolved particle fluxes using a continuous-flow Hygroscopicity-Resolved Relaxed Eddy Accumulation (Hy-Res REA) technique. The different components of the instrument were extensively tested inside the US Environmental Protection Agency's Aerosol Test Facility for sea-salt and ammoniums sulfate particle fluxes. The new REA system design does not require particle accumulation, therefore avoids the diffusional wall losses associated with long residence times of particles inside the air collectors of the traditional REA devices. The Hy-Res REA system used in this study includes a 3-D sonic anemometer, two fast-response solenoid valves, two Condensation Particle Counters (CPCs), a Scanning Mobility Particle Sizer (SMPS), and a Hygroscopicity Tandem Differential Mobility Analyzer (HTDMA). A linear relationship was found between the sea-salt particle fluxes measured by eddy covariance and REA techniques, with comparable theoretical (0.34) and measured (0.39) proportionality constants. The sea-salt particle detection limit of the Hy-Res REA flux system is estimated to be 6x105 m-2s-1. For the conditions of ammonium sulfate and sea-salt particles of comparable source strength and location, the continuous-flow Hy-Res REA instrument was able to achieve better than 90% accuracy of measuring the sea-salt particle fluxes. In principle, the instrument can be applied to measure fluxes of particles of variable size and distinct hygroscopic properties (i.e., mineral dust, black carbon, etc.).

Sulphur and oxygen isotopic compositions of groundwater and sabkha - sulphate in the Middle East

International Nuclear Information System (INIS)

Robinson, B.W.

1987-01-01

The climate and topography of landward margins around the southern Mediterranean and the Arabian Gulf have given rise to areas of recent evaporite formation known as 'sabkhas'. These supratidal evaporitic flats have developed as a result of a relative fall in sea level after the last marine transgression (about 4000 years B.P.) which deposited carbonate sediments over coastal areas. Inland sabkhas may also develop in low lying areas and the desert 'soils' often have a 'getch' (duricrust) layer of gypsum or calcite near the surface. Published sulphur isotope studies of the sabkhas in the Gulf of Sirte (Libyan Arab Jamahiriya), Al Khiran (Kuwait) and Abu Dhabi (United Arab Emirates) indicate a sea water influence (δ 34 S ≅ +21 per mille; δ 18 O ≅ +10 per mille) only in the outer sabkha. At Al Khiran, Gulf of Sirte and Bardawil (Egypt) the δ 34 S values decrease to +14 per mille on the landward side. Continental sabkhas in the United Arab Emirates have δ 34 S values between +13 and +16 per mille and the continental getch in Kuwait has δ 34 S=+15.6 per mille. Sulphate minerals from the Al Khiran sabkha have δ 34 S and δ 18 O values up to +17 and +16 per mille respectively, much lower than at Abu Dhabi, where sea water sulphate and bacterial activity are more prevalent. At Al Khiran the δ 34 S mineral values drop to +12 per mille and the spread is connected with mineral transformations. In the Libyan Arab Jamahiriya and the United Arab Emirates the continental sulphate was thought to be derived from Cretaceous sediments. However, in Kuwait, an aquiclude, the Rus Formation (L. Eocene), prevents older water and sulphate from entering the sabkhas. This widespread sulphate source with δ 34 S=+14 per mille may be derived from continental getch and surface evaporites which are transported and homogenized by dust storms. (author). 10 refs, 4 figs

Effect of mixed vs single brine composition on salt weathering in porous carbonate building stones for different environmental conditions

Czech Academy of Sciences Publication Activity Database

Menéndez, B.; Petráňová, Veronika

2016-01-01

Roč. 210, August (2016), s. 124-139 ISSN 0013-7952 R&D Projects: GA MŠk(CZ) LO1219 Keywords : salt weathering * limestone * environmental conditions * sodium chloride * sodium sulphate * calcium sulphate * salt mixture Subject RIV: AL - Art, Architecture, Cultural Heritage Impact factor: 2.569, year: 2016 http://www.sciencedirect.com/science/article/pii/S0013795216301879

Plathelminth abundance in North Sea salt marshes: environmental instability causes high diversity

Science.gov (United States)

Armonies, Werner

1986-09-01

Although supralittoral salt marshes are habitats of high environmental instability, the meiofauna is rich in species and abundance is high. The community structure of free-living Plathelminthes (Turbellaria) in these salt marshes is described. On an average, 104 individuals are found below an area of 10 cm2. The average species density in ungrazed salt marshes is 11.3 below 10 cm2 and 45.2 below 100 cm2, indicating strong small-scale heterogenity. The faunal similarity between sediment and the corresponding above-ground vegetation is higher than between adjacent sample sites. Species prefer distinct ranges of salinity. In the lower part of the supralittoral salt marshes, the annual fluctuations of salinity are strongest and highly unpredictable. This region is richest in plathelminth species and abundance; diversity is highest, and the faunal composition of parallel samples is quite similar. In the upper part of the supralittoral salt marshes, the annual variability of salinity is lower, plathelminths are poor in species diversity and abundance. Parallel samples often have no species in common. Thus, those salt marsh regions with the most unstable environment are inhabited by the most diverse species assemblage. Compared to other littoral zones of the North Sea, however, plathelminth diversity in salt marshes is low. The observed plathelminth diversity pattern can apparently be explained by the “dynamic equilibrium model” (Huston, 1979).

Chemical characterisation of himalayan rock salt

International Nuclear Information System (INIS)

Hassan, A.U.; Din, M.U.

2017-01-01

Present study involves the chemical evaluation of rock salt samples collected from the plugging sites of Himalayan salt (Khewra salt mines and Kalabagh salt mines) for their moisture content, water insoluble matter, calcium, magnesium, sulphate content and trace minerals such as Fe,Cu,Cd,Pb,As,Ag and Zn determined by atomic absorption spectroscopy. Moisture content of Khewra and Kalabagh salt samples ranged from 0.03 wt. % to 0.09 wt. % and 0.06 % to 0.08 %, respectively. Water insoluble matter ranged from 0.08 wt. % to 1.4 wt. % and 1.5 wt. % to 2.8wt. % for Khewra and Kalabagh salt samples, respectively. Sulphate content for Khewra salt sample was from 0.39 % to 0.91 % and for Kalabagh salt mines from 0.75 wt. % to 0.95 wt. %. For Khewra salt mines calcium ranged 0.15 wt. % to 0.32 wt. % and for Kalabagh salt samples from 0.1 wt. % to 0.27 wt. %. Magnesium ranged from 0.11 wt. % to 0.35 wt. % for Khewra salt mines, while for Kalabagh salt samples its range was 0.18 wt. % to 0.89 wt. %. Trace metals had the concentration ranges between 0.2 to 1.85 mg/kg for copper; between 0.21 to 0.42 mg/kg for manganese; between 0.04 to 0.06 mg/kg for zinc; between 0.12 to 0.18 mg/kg for arsenic and between 0.03 and 0.05 mg/kg for lead while cadmium content was either below the method's detection limits or in very trace amounts. The results show that the concentrations of all the parameters studied are below the limits set by World Health Organization (WHO) and Food and Agriculture Organization (FAO). Therefore, it can be concluded from the paper that the Himalayan salt from the plugging sites of Khewra and Kalabagh salt mines are safe to use. (author)

Effect of sea-level rise on salt water intrusion near a coastal well field in southeastern Florida.

Science.gov (United States)

Langevin, Christian D; Zygnerski, Michael

2013-01-01

A variable-density groundwater flow and dispersive solute transport model was developed for the shallow coastal aquifer system near a municipal supply well field in southeastern Florida. The model was calibrated for a 105-year period (1900 to 2005). An analysis with the model suggests that well-field withdrawals were the dominant cause of salt water intrusion near the well field, and that historical sea-level rise, which is similar to lower-bound projections of future sea-level rise, exacerbated the extent of salt water intrusion. Average 2005 hydrologic conditions were used for 100-year sensitivity simulations aimed at quantifying the effect of projected rises in sea level on fresh coastal groundwater resources near the well field. Use of average 2005 hydrologic conditions and a constant sea level result in total dissolved solids (TDS) concentration of the well field exceeding drinking water standards after 70 years. When sea-level rise is included in the simulations, drinking water standards are exceeded 10 to 21 years earlier, depending on the specified rate of sea-level rise. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

Soluble salt sources in medieval porous limestone sculptures: A multi-isotope (N, O, S) approach

Energy Technology Data Exchange (ETDEWEB)

Kloppmann, W., E-mail: w.kloppmann@brgm.fr [BRGM, Direction des Laboratoires, Unité Isotopes, BP 6009, F-45060 Orléans cedex 2 (France); Rolland, O., E-mail: olivierrolland@wanadoo.fr [Montlouis-sur-Loire (France); Proust, E.; Montech, A.T. [BRGM, Direction des Laboratoires, Unité Isotopes, BP 6009, F-45060 Orléans cedex 2 (France)

2014-02-01

The sources and mechanisms of soluble salt uptake by porous limestone and the associated degradation patterns were investigated for the life-sized 15th century “entombment of Christ” sculpture group located in Pont-à-Mousson, France, using a multi-isotope approach on sulphates (δ{sup 34}S and δ{sup 18}O) and nitrates (δ{sup 15}N and δ{sup 18}O). The sculpture group, near the border of the Moselle River, is within the potential reach of capillary rise from the alluvial aquifer. Chemical analyses show a vertical zonation of soluble salts with a predominance of sulphates in the lower parts of the statues where crumbling and blistering prevail, and higher concentrations of nitrates and chloride in the high parts affected by powdering and efflorescence. Isotope fingerprints of sulphates suggest a triple origin: (1) the lower parts are dominated by capillary rise of dissolved sulphate from the Moselle water with characteristic Keuper evaporite signatures that progressively decreases with height; (2) in the higher parts affected by powdering the impact of atmospheric sulphur becomes detectable; and (3) locally, plaster reparations impact the neighbouring limestone through dissolution and re-precipitation of gypsum. Nitrogen and oxygen isotopes suggest an organic origin of nitrates in all samples. N isotope signatures are compatible with those measured in the alluvial aquifer of the Moselle River further downstream. This indicates contamination by sewage or organic fertilisers. Significant isotopic contrasts are observed between the different degradation features depending on the height and suggest historical changes of nitrate sources. - Highlights: • We use S, N and O isotopes to distinguish salt sources in limestone sculptures. • Vertical zonation of degradation is linked to capillary rise and air pollution. • Sulphate salts in lower parts are derived from river/groundwater. • Sulphate salts in higher parts show signature of air pollution. • Nitrates

Thalassiolin D: a new flavone O-glucoside Sulphate from the seagrass Thalassia hemprichii.

Science.gov (United States)

Hawas, Usama W; Abou El-Kassem, Lamia T

2017-10-01

Thalassiolin D, a new flavone O-glucoside sulphate along with three flavonoids, two steroids, p-hydroxybenzoic acid, 4,4'-dihydroxybenzophenone and nitrogen compound, octopamine were isolated from the seagrass Thalassia hemprichii, collected from the Saudi Red Sea coast. By extensive spectroscopic analysis including 1D and 2D NMR and MS data, the structure of the new compound was elucidated as diosmetin 7-O-β-glucosyl-2″-sulphate. The new compound displayed moderately in vitro antiviral HCV protease activity with IC 50 value 16 μM.

Evaluation of the salt deposition on the canister surface of concrete cask. Part 2. Measurement test of the salt concentration in air and salt deposition in the field

International Nuclear Information System (INIS)

Wataru, Masumi

2012-01-01

Concerning the storage facility of spent nuclear fuel using the concrete cask, there is an issue of stress corrosion cracking(SCC). The cooling air goes up along the canister surface in the concrete cask. To evaluate the initiation of SCC or rusting, it is important to verify the estimation method of the sea salt deposition on the metal canister surface transported by cooling air including sea salt particles. To measure the deposition rate, field tests were performed in Choushi test center. In the field test, it was found that the amount of sea salt deposition was very low because the density of the atmospheric sea salt concentration was very low compared with the laboratory test. Using relation between laboratory data and filed data, it is possible to evaluate the salt deposition rate on the canister surface. We also measured atmospheric sea salt concentration in Choushi test center to make the environment condition clear and compared the measurement data with the calculation data to verify the evaluation model. We are developing the automatic measuring device for atmospheric sea salt concentration. To check its performance, we are measuring atmospheric sea salt concentration in Yokosuka Area of CRIEPI and it was confirmed that the device works for one month automatically and fulfills its specifications. (author)

Precipitation of calcium sulphate on hot walls - influence of impurities, thermal and hydraulic effects

International Nuclear Information System (INIS)

Guillermin, Roger

1973-01-01

After some generalities on desalination by distillation processes and on problems due to scaling, this research thesis aims at a better understanding of the formation of deposits and their effects in the case of precipitation of calcium sulphate hemihydrate which precipitates above 100 C in pure solution and between 100 and 300 C in brine. Deposit growth, influence of impurities, and influence of the deposit on heat exchange and loss of load are the main issues of this research. The author addresses general principles of salt crystallization and the thermodynamic and kinetic aspects of calcium sulphate precipitation, studies the growth kinetics of the calcium sulphate hemihydrate in a transient concentration regime, reports the study of thermal and hydraulic effects of the formation of a hemihydrate deposit, notably by discussing the different phases involved in the covering of a metallic surface

TEM study of soot, organic aerosol, and sea-salt particles collected during CalNex

Science.gov (United States)

Adachi, K.; Buseck, P. R.

2010-12-01

Anthropogenic aerosol particles are emitted in abundance from megacities. Those particles can have important effects on both human health and climate. In this study, aerosol particles having aerodynamic diameters between 50 and 300 nm were collected during the CalNex campaign at the Pasadena ground site from May 15 to June 15, 2010, ~15 km northeast of downtown Los Angeles. The samples were analyzed using transmission electron microscopes (TEMs) to characterize particle shapes and compositions. Most samples are dominated by soot, organic aerosol (OA), sulfate, sea salt, or combinations thereof. Sizes and amounts of OA particles increased during the afternoons, and most soot particles were internally mixed with OA and sulfate in the afternoons. The proportion of soot to other material in individual particles increased and soot particles were more compact during the nights and early mornings. Sea-salt particles were commonly internally mixed with other materials. They have high Na contents with lesser N, Mg, S, K, and Ca and almost no Cl, suggesting that the Cl was replaced by sulfate or nitrate in the atmosphere. There is less OA and more sea salt and sulfate in the CalNex samples than in the samples from Mexico City that were collected during the MILAGRO campaign. Our study indicates that compositions of internally mixed aerosol particles and shapes of soot particles change significantly within a day. These changes probably influence the estimates of their effects on human health and climate.

The vapour pressures over saturated aqueous solutions of cadmium chloride, cadmium bromide, cadmium iodide, cadmium nitrate, and cadmium sulphate

International Nuclear Information System (INIS)

Apelblat, Alexander; Korin, Eli

2007-01-01

Vapour pressures of water over saturated solutions of cadmium salts (chloride, bromide, iodide, nitrate, and sulphate) were determined over the temperature range 280 K to 322 K and compared with the literature data. The vapour pressures determined were used to obtain the water activities, osmotic coefficients and the molar enthalpies of vaporization in the (cadmium salt + water) systems

The vapour pressures over saturated aqueous solutions of cadmium chloride, cadmium bromide, cadmium iodide, cadmium nitrate, and cadmium sulphate

Energy Technology Data Exchange (ETDEWEB)

Apelblat, Alexander [Department of Chemical Engineering, Ben Gurion University of the Negev, P.O. Box 653, Beer Sheva 84105 (Israel)]. E-mail: apelblat@bgu.ac.il; Korin, Eli [Department of Chemical Engineering, Ben Gurion University of the Negev, P.O. Box 653, Beer Sheva 84105 (Israel)

2007-07-15

Vapour pressures of water over saturated solutions of cadmium salts (chloride, bromide, iodide, nitrate, and sulphate) were determined over the temperature range 280 K to 322 K and compared with the literature data. The vapour pressures determined were used to obtain the water activities, osmotic coefficients and the molar enthalpies of vaporization in the (cadmium salt + water) systems.

Evaluation of the salt deposition on the canister surface of concrete cask. Part 3. Long-term measurement of salt concentration in air and evaluation of the salt deposition

International Nuclear Information System (INIS)

Wataru, Masumi; Takeda, Hirofumi

2015-01-01

To realize the dry storage using concrete cask in Japan, it is important to develop the evaluation method of the SCC of the canister. One of the key issues is sea salt deposition on the canister surface during the storage period. If the amount of salt deposition exceeds the critical value, the SCC may occur. The amount of salt deposition depends on the ambient air condition. We developed the measurement device of salt in air to make clear the ambient condition. The device sucks the air including sea salt and the sea salt dissolves in water. We analyze the water including sea salt. This device works automatically for one or two months. In this study, the performance of this device was verified comparing the data obtained by the air sampler using filter pack. In Yokosuka area of CRIEPI, we measured the ambient air condition using this device for three years. Furthermore, we performed the salt deposition test using the small ducts in the same area. The ambient air including sea salt flows in the duct and the sea salt deposits on the test specimen put on the duct inner surface. We took out the specimen after certain time and measured the salt amount on the test specimen. Using these data, we obtained the relation between the salt deposition and the time on this ambient condition. The results of this study are useful to evaluate the SCC of the canister. (author)

Recovery from acidification of lochs in Galloway, south-west Scotland, UK: 1979-1998

Directory of Open Access Journals (Sweden)

R. C. Ferrier

2001-01-01

Full Text Available The Galloway region of south-west Scotland has historically been subject to long-term deposition of acidic precipitation which has resulted in acidification of soils and surface waters and subsequent damage to aquatic ecology. Since the end of the 1970s, however, acidic deposition has decreased substantially. The general pattern is for a rapid decline in non-marine sulphate in rainwater over the period 1978-1988 followed by stable concentrations to the mid-1990s. Concentrations of nitrate and ammonium in deposition have remained constant between 1980 and 1998. Seven water quality surveys of 48 lochs in the Galloway region have been conducted between 1979 and 1998. During the first 10 years, from 1979, there was a major decline in regional sulphate concentrations in the lochs, which was expected to have produced a decline in base cations and an increase in the acid neutralising capacity. But sea-salt levels (as indicated by chloride concentrations were approximately 25% higher in 1988 than in 1979 and thus short-term acidification due to sea-salts offset much of the long-term recovery trend expected in the lochs. During the next 10 years, however, the chloride concentrations returned to 1979 levels and the lochs showed large increases in acid neutralising capacity despite little change in sulphate concentrations. From the observed decline in sulphate deposition and concentrations of sulphate in the lochs, it appears that approximately 75% of the possible improvement in acid neutralising capacity has already occurred over the 20-year period (1979-1998. The role of acid deposition as a driving factor for change in water chemistry in the Galloway lochs is confounded by concurrent changes in other driving variables, most notably, factors related to episodic and year-to-year variations in climate. In addition to inputs of sea-salts, climate probably also influences other chemical signals such as peaks in regional nitrate concentrations and the sharp

Anthropogenic influence on the distribution of tropospheric sulphate aerosol

Energy Technology Data Exchange (ETDEWEB)

Langner, J; Rodhe, H; Crutzen, P J; Zimmermann, P [Swedish Meteorological and Hydrological Institute, Norrkoeping (Sweden)

1992-10-22

Human activities have increased global emissions of sulphur gases by about a factor of three during the past century, leading to increased sulphate aerosol concentrations, mainly in the Northern Hemisphere. Sulphate aerosols can affect the climate directly, by increasing the backscattering of solar radiation in cloud-free air, and indirectly, by providing additional cloud condensation nuclei. Here a global transport-chemistry model is used to estimate the changes in the distribution of tropospheric sulphate aerosol and deposition of non-seasalt sulphur that have occurred since pre-industrial times. The increase in sulphate aerosol concentration is small over the Southern Hemisphere oceans, but reaches a factor of 100 over northern Europe in winter. Calculations indicate, however, that at most 6% of the anthropogenic sulphur emissions is available for the formation of new aerosol particles. This is because about one-half of the sulphur dioxide is deposited on the Earth's surface, and most of the remainder is oxidized in cloud droplets so that the sulphate becomes associated with pre-existing particles. Even so, the rate of formation of new sulphate particles may have doubled since pre-industrial times. 18 refs., 3 figs.

The Reclamation of Industrial Wastes Inclusive Sulphates by Sulphate-Reducing Bacteria

Directory of Open Access Journals (Sweden)

Mária Kušnierová

2004-12-01

Full Text Available The objective of our study was to verify experimentally the possibility of using coal mine drainage and gypsum from the „stabilizate“ (the final product from the combustion desulphurisation as the source of sulphate for the cultivation of SRB with the prospect of: purging of mine waste waters inclusive sulphates, recycling of desulphurisation agent (limestone and production of elemental sulphur from hydrogen sulphide. The results confirmed the theoretical assumptions on the use of gypsum, which forms the substantial component of „stabilizate“, as the source of sulphate for sulphate-reducing bacteria, which produce hydrogen sulphide in the process of bacterial reduction of sulphates. They also showed the possibility of recycling the desulphurisation agent – limestone, as well as the realistic alternative of using „stabilizate“ in the production of elemental sulphur which still represents an important raw material needed in chemical, paper or other industries.

Effect of temperature on sulphate reduction, growth rate and growth yield in five psychrophilic sulphate-reducing bacteria from Arctic sediments

DEFF Research Database (Denmark)

Knoblauch, C.; Jørgensen, BB

1999-01-01

and T(opt). For strains LSv21 and LSv514, however, growth yields were highest at the lowest temperatures, around 0 degrees C. The results indicate that psychrophilic sulphate-reducing bacteria are specially adapted to permanently low temperatures by high relative growth rates and high growth yields......Five psychrophilic sulphate-reducing bacteria (strains ASv26, LSv21, PSv29, LSv54 and LSv514) isolated from Arctic sediments were examined for their adaptation to permanently low temperatures, All strains grew at -1.8 degrees C, the freezing point of sea water, but their optimum temperature...... for growth (T(opt)) were 7 degrees C (PSv29), 10 degrees C (ASv26, LSv54) and 18 degrees C (LSv21, LSv514), Although T(opt) was considerably above the in situ temperatures of their habitats (-1.7 degrees C and 2.6 degrees C), relative growth rates were still high at 0 degrees C, accounting for 25...

Recovery from episodic acidification delayed by drought and high sea salt deposition

Directory of Open Access Journals (Sweden)

H. Laudon

2008-03-01

Full Text Available For the prediction of episodic acidification large uncertainties are connected to climatic variability and its effect on drought conditions and sea-salt episodes. In this study data on 342 hydrological episodes in 25 Swedish streams, sampled over 10 years, have been analyzed using a recently developed episode model. The results demonstrate that drought is the most important factor modulating the magnitude of the anthropogenic influence on pH and ANC during episodes. These modulating effects are especially pronounced in southern and central Sweden, where the historically high acid deposition has resulted in significant S pools in catchment soils. The results also suggest that the effects of episodic acidification are becoming less severe in many streams, but this amelioration is less clear in coastal streams subject to high levels of sea-salt deposition. Concurrently with the amelioration of the effects of episodic acidification, regional climate models predict that temperatures will increase in Sweden during the coming decades, accompanied by reductions in summer precipitation and more frequent storms during fall and winter in large areas of the country. If these predictions are realized delays in streams' recovery from episodic acidification events can be expected.

A natural analogue for near-field behaviour in a high level radioactive waste repository in salt: the Salton Sea geothermal field, California, USA

International Nuclear Information System (INIS)

Elders, W.A.

1987-01-01

In the Salton Sea Geothermal Field (SSGF), in the sediments of the delta of the Colorado River, we are developing a three-dimensional picture of active water/rock reactions at temperatures of 0 C and salinities of 7 to 25 weight percent to produce quantitative data on mineral stabilities and mobilities of naturally-occurring radio-nuclides. The aim is to produce data to validate geochemical computer codes being developed to assess the performance of a Commercial High-Level Waste (CHLW) repository in salt. Among the findings to date are: (1) greenschist facies metamorphism is occurring; (2) brine compositions are fairly similar to those expected in candidate salt repository sites; (3) U and Th concentrations in the rocks are typical for sedimentary rocks; (4) the brines are enriched in Na, Mn, Zn, Sr, Ra Po and strongly depleted in U and Th relative to the rocks; (5) significant radioactive disequilibria exist in brines and solid phases of the SSGF. The disequilibria in the actinide series allow estimation of the rates of brine-rock interaction and understanding of hydrologic processes and radionuclide behaviour. Work is continuing emphasizing the reactions of authigenic clay minerals, epidotes, feldspars, chlorites and sulphates. So far, adapting geochemical codes to the necessary combination of high salinity and high temperature has lagged behind the natural analogue study of the SSGF so that validation is still in progress. In the future our data can be also used in validating performance assessment codes which couple geochemistry and transport processes, and in design of waste packages and back fill compositions. (author)

Sulfate-Reducing Prokaryotes from North Sea Oil reservoirs; organisms, distribution and origin

Energy Technology Data Exchange (ETDEWEB)

Beeder, Janiche

1997-12-31

During oil production in the North Sea, anaerobic seawater is pumped in which stimulates the growth of sulphate-reducing prokaryotes that produce hydrogen sulphide. This sulphide causes major health hazards, economical and operational problems. As told in this thesis, several strains of sulphate reducers have been isolated from North Sea oil field waters. Antibodies have been produced against these strains and used to investigate the distribution of sulphate reducers in a North Sea oil reservoir. The result showed a high diversity among sulphate reducers, with different strains belonging to different parts of the reservoir. Some of these strains have been further characterized. The physiological and phylogenetic characterization showed that strain 7324 was an archaean. Strain A8444 was a bacterium, representing a new species of a new genus. A benzoate degrading sulphate reducing bacterium was isolated from injection water, and later the same strain was detected in produced water. This is the first field observations indicating that sulphate reducers are able to penetrate an oil reservoir. It was found that the oil reservoir contains a diverse population of thermophilic sulphate reducers able to grow on carbon sources in the oil reservoir, and to live and grow in this extreme environment of high temperature and pressure. The mesophilic sulphate reducers are established in the injection water system and in the reservoir near the injection well during oil production. The thermophilic sulphate reducers are able to grow in the reservoir prior to, as well as during production. It appears that the oil reservoir is a natural habitat for thermophilic sulphate reducers and that they have been present in the reservoir long before production started. 322 refs., 9 figs., 11 tabs.

Sulfate-Reducing Prokaryotes from North Sea Oil reservoirs; organisms, distribution and origin

Energy Technology Data Exchange (ETDEWEB)

Beeder, Janiche

1996-12-31

During oil production in the North Sea, anaerobic seawater is pumped in which stimulates the growth of sulphate-reducing prokaryotes that produce hydrogen sulphide. This sulphide causes major health hazards, economical and operational problems. As told in this thesis, several strains of sulphate reducers have been isolated from North Sea oil field waters. Antibodies have been produced against these strains and used to investigate the distribution of sulphate reducers in a North Sea oil reservoir. The result showed a high diversity among sulphate reducers, with different strains belonging to different parts of the reservoir. Some of these strains have been further characterized. The physiological and phylogenetic characterization showed that strain 7324 was an archaean. Strain A8444 was a bacterium, representing a new species of a new genus. A benzoate degrading sulphate reducing bacterium was isolated from injection water, and later the same strain was detected in produced water. This is the first field observations indicating that sulphate reducers are able to penetrate an oil reservoir. It was found that the oil reservoir contains a diverse population of thermophilic sulphate reducers able to grow on carbon sources in the oil reservoir, and to live and grow in this extreme environment of high temperature and pressure. The mesophilic sulphate reducers are established in the injection water system and in the reservoir near the injection well during oil production. The thermophilic sulphate reducers are able to grow in the reservoir prior to, as well as during production. It appears that the oil reservoir is a natural habitat for thermophilic sulphate reducers and that they have been present in the reservoir long before production started. 322 refs., 9 figs., 11 tabs.

Coastal acid sulphate soils in Poland: a review

Directory of Open Access Journals (Sweden)

Hulisz Piotr

2017-03-01

Full Text Available This paper presents the state of knowledge on coastal acid sulphate soils in Poland. The properties of these soils are closely related to the influence of brackish water from the Baltic Sea, high accumulation of organic matter and human activity. The obtained results demonstrate that the sulphide accumulation in soils refers to a relatively small areas of the Polish coastal zone with the unique and very valuable habitats. They require an adequate regulation of the water relations to avoid the risk of strong soil acidification and environmental pollution by heavy metals. Currently, there are no relevant criteria for classification of acid sulphate soil materials in the Polish Soil Classification (2011. Therefore, based on the presented data, the authors proposed to identify these features at the lower classification level (for different soil types. The criteria for the Thionic and Sulfidic qualifiers used in the WRB classification (IUSS Working Group WRB 2015 could be accepted for this purpose.

Determination of pollution for the effect of sea salt aerosols corrosion

International Nuclear Information System (INIS)

Nakayasu, Fumio; Umehara, Toshihiro; Mizutani, Masatoshi; Matsukawa, Kiyokazu

2007-01-01

All of 15 nuclear power plants in Fukui Prefecture are located in the Japan Sea Coast. Corrosion is strongly influenced by material and environmental factors. We installed the salt damage experimental yard at Awara sea coast in March, 2006. We are doing the open air test, sheltered test without filter and with filter. The corrosivity of carbon steel of winter was higher than it of summer at Awara facility. The measurement of chloride deposition rate was done by the dry gauze method. The correlation between chloride deposition rate and the average velocity of the wind was found. The correlation between chloride deposition rate and the average rainfall was a little complicate. It means the chloride deposition rate has maximum value at a certain rainfall amount. No other clear relation was found. (author)

Salt marsh as a coastal filter for the oceans: changes in function with experimental increases in nitrogen loading and sea-level rise.

Science.gov (United States)

Nelson, Joanna L; Zavaleta, Erika S

2012-01-01

Coastal salt marshes are among Earth's most productive ecosystems and provide a number of ecosystem services, including interception of watershed-derived nitrogen (N) before it reaches nearshore oceans. Nitrogen pollution and climate change are two dominant drivers of global-change impacts on ecosystems, yet their interacting effects at the land-sea interface are poorly understood. We addressed how sea-level rise and anthropogenic N additions affect the salt marsh ecosystem process of nitrogen uptake using a field-based, manipulative experiment. We crossed simulated sea-level change and ammonium-nitrate (NH(4)NO(3))-addition treatments in a fully factorial design to examine their potentially interacting effects on emergent marsh plants in a central California estuary. We measured above- and belowground biomass and tissue nutrient concentrations seasonally and found that N-addition had a significant, positive effect on a) aboveground biomass, b) plant tissue N concentrations, c) N stock sequestered in plants, and d) shoot:root ratios in summer. Relative sea-level rise did not significantly affect biomass, with the exception of the most extreme sea-level-rise simulation, in which all plants died by the summer of the second year. Although there was a strong response to N-addition treatments, salt marsh responses varied by season. Our results suggest that in our site at Coyote Marsh, Elkhorn Slough, coastal salt marsh plants serve as a robust N trap and coastal filter; this function is not saturated by high background annual N inputs from upstream agriculture. However, if the marsh is drowned by rising seas, as in our most extreme sea-level rise treatment, marsh plants will no longer provide the ecosystem service of buffering the coastal ocean from eutrophication.

Temporal variation of accumulation rates on a natural salt marsh in the 20th century determined by 137Cs chronologies – the impact of sea level rise and increased inundation frequency

DEFF Research Database (Denmark)

Andersen, Thorbjørn Joest; Svinth, Steffen; Pejrup, Morten

2011-01-01

Salt marshes are potentially threatened by sea level rise if sediment supply is unable to balance the rising sea. A rapid sea level rise is one of the pronounced effects of global warming and global sea level is at present rising at an elevated rate of about 3.4 mm y-1 on average. This increasing...... in sediment deposition is significant and gives reason for concern as it may be the first sign of a sedimentation deficiency which could be threatening this and other salt marshes in the case of a rapidly rising sea level. Our work demonstrates that the assumption of a constant relationship between salt marsh...... with salt marsh accretion is most probably not valid in the present case study and it may well be that this is also the case for many other salt marshes, especially if sea level continues to rise rapidly as indicated by some climate change scenarios....

Investigating the Changes of Sulphate in Potabale Water of Yasuj City and preparing it's Qualitative Plan by Means of GIS Tools

International Nuclear Information System (INIS)

Pasereh, F.; Hasani, A.; Hoseini, N.; Javid, A.

2016-01-01

Water has always some soluble salts, such as sulphate. Sulphate enters the water through different resources such as, dissolved gypsum, waste water of industrial factories and automobiles smoke, dissolved in rain. Presence of sulphate in potable water has an enormous role in creating constant hardness.On the other hand Presence of sulphate with high density in drinking water, causes changes in taste and it's combination with Calcium and Magnesium anions has laxative effect. The goal of this study is to assess the amount of existing sulphate in Yasuj city potable ground water, and determining the procedure of changes in chemical parameters of sulphate and recognizing effective factors on these parameters and preparing qualitative plan for water resources for sulphate parameter by means of GIS tools. Method: In the study described above, 42 specimens in the 7 early months of the year 1387 were acquired and tested. Sulphate tests were done based on the measuring method of the instrument of Filter photometer (Model: 7000). For analysing the results, Excel software and for preparing qualitative plan, GIS software was used. Findings: This study showed that sulfate levels in water resources by reducing water level in summer and autumn and with a water level of under ground water resources increases. Discussion and Conclusion: Decrease of ground water resources of Yasuj city, causes the sulphate density to increase.

Salt marsh as a coastal filter for the oceans: changes in function with experimental increases in nitrogen loading and sea-level rise.

Directory of Open Access Journals (Sweden)

Joanna L Nelson

Full Text Available Coastal salt marshes are among Earth's most productive ecosystems and provide a number of ecosystem services, including interception of watershed-derived nitrogen (N before it reaches nearshore oceans. Nitrogen pollution and climate change are two dominant drivers of global-change impacts on ecosystems, yet their interacting effects at the land-sea interface are poorly understood. We addressed how sea-level rise and anthropogenic N additions affect the salt marsh ecosystem process of nitrogen uptake using a field-based, manipulative experiment. We crossed simulated sea-level change and ammonium-nitrate (NH(4NO(3-addition treatments in a fully factorial design to examine their potentially interacting effects on emergent marsh plants in a central California estuary. We measured above- and belowground biomass and tissue nutrient concentrations seasonally and found that N-addition had a significant, positive effect on a aboveground biomass, b plant tissue N concentrations, c N stock sequestered in plants, and d shoot:root ratios in summer. Relative sea-level rise did not significantly affect biomass, with the exception of the most extreme sea-level-rise simulation, in which all plants died by the summer of the second year. Although there was a strong response to N-addition treatments, salt marsh responses varied by season. Our results suggest that in our site at Coyote Marsh, Elkhorn Slough, coastal salt marsh plants serve as a robust N trap and coastal filter; this function is not saturated by high background annual N inputs from upstream agriculture. However, if the marsh is drowned by rising seas, as in our most extreme sea-level rise treatment, marsh plants will no longer provide the ecosystem service of buffering the coastal ocean from eutrophication.

Nuclear risk reduction study. The effect of sea salt aerosols in the Japan sea coast facilities

International Nuclear Information System (INIS)

Nakayasu, Fumio

2007-01-01

All of 15 nuclear power plants in Fukui Prefecture are located in the Japan Sea Coast. Corrosion is strongly influenced by material and environmental factors. We installed the salt damage experimental yard at Awara sea coast in March, 2006. We are doing the open air test, sheltered test without filter and with filter. The carbon steel standard specimen were exposed under three kinds of test conditions mentioned above. The corrosivity of the open air test specimens was higher than it of Miyako Island, Okinawa. The corrosivity of carbon steel of winter was higher than it of summer. The measurement of chloride deposition rate was done by the dry gauze method. The correlation between chloride deposition rate and the average velocity of the wind was found. The correlation between chloride deposition rate and the average rainfall was a little complicate. It means the chloride deposition rate has maximum value at a certain rainfall amount. No other clear relation was found. (author)

Carbon burial and storage in tropical salt marshes under the influence of sea level rise.

Science.gov (United States)

Ruiz-Fernández, A C; Carnero-Bravo, V; Sanchez-Cabeza, J A; Pérez-Bernal, L H; Amaya-Monterrosa, O A; Bojórquez-Sánchez, S; López-Mendoza, P G; Cardoso-Mohedano, J G; Dunbar, R B; Mucciarone, D A; Marmolejo-Rodríguez, A J

2018-07-15

Coastal vegetated habitats can be important sinks of organic carbon (C org ) and mitigate global warming by sequestering significant quantities of atmospheric CO 2 and storing sedimentary C org for long periods, although their C org burial and storage capacity may be affected by on-going sea level rise and human intervention. Geochemical data from published 210 Pb-dated sediment cores, collected from low-energy microtidal coastal wetlands in El Salvador (Jiquilisco Bay) and in Mexico (Salada Lagoon; Estero de Urias Lagoon; Sian Ka'an Biosphere Reserve) were revisited to assess temporal changes (within the last 100years) of C org concentrations, storage and burial rates in tropical salt marshes under the influence of sea level rise and contrasting anthropization degree. Grain size distribution was used to identify hydrodynamic changes, and δ 13 C to distinguish terrigenous sediments from those accumulated under the influence of marine transgression. Although the accretion rate ranges in all sediment records were comparable, C org concentrations (0.2-30%), stocks (30-465Mgha -1 , by extrapolation to 1m depth), and burial rates (3-378gm -2 year -1 ) varied widely within and among the study areas. However, in most sites sea level rise decreased C org concentrations and stocks in sediments, but increased C org burial rates. Lower C org concentrations were attributed to the input of reworked marine particles, which contribute with a lower amount of C org than terrigenous sediments; whereas higher C org burial rates were driven by higher mass accumulation rates, influenced by increased flooding and human interventions in the surroundings. C org accumulation and long-term preservation in tropical salt marshes can be as high as in mangrove or temperate salt marsh areas and, besides the reduction of C org stocks by ongoing sea level rise, the disturbance of the long-term buried C org inventories might cause high CO 2 releases, for which they must be protected as a part of

Exploring mechanisms of compaction in salt-marsh sediments using Common Era relative sea-level reconstructions

Science.gov (United States)

Brain, Matthew J.; Kemp, Andrew C.; Hawkes, Andrea D.; Engelhart, Simon E.; Vane, Christopher H.; Cahill, Niamh; Hill, Troy D.; Donnelly, Jeffrey P.; Horton, Benjamin P.

2017-07-01

Salt-marsh sediments provide precise and near-continuous reconstructions of Common Era relative sea level (RSL). However, organic and low-density salt-marsh sediments are prone to compaction processes that cause post-depositional distortion of the stratigraphic column used to reconstruct RSL. We compared two RSL reconstructions from East River Marsh (Connecticut, USA) to assess the contribution of mechanical compression and biodegradation to compaction of salt-marsh sediments and their subsequent influence on RSL reconstructions. The first, existing reconstruction ('trench') was produced from a continuous sequence of basal salt-marsh sediment and is unaffected by compaction. The second, new reconstruction is from a compaction-susceptible core taken at the same location. We highlight that sediment compaction is the only feasible mechanism for explaining the observed differences in RSL reconstructed from the trench and core. Both reconstructions display long-term RSL rise of ∼1 mm/yr, followed by a ∼19th Century acceleration to ∼3 mm/yr. A statistically-significant difference between the records at ∼1100 to 1800 CE could not be explained by a compression-only geotechnical model. We suggest that the warmer and drier conditions of the Medieval Climate Anomaly (MCA) resulted in an increase in sediment compressibility during this time period. We adapted the geotechnical model by reducing the compressive strength of MCA sediments to simulate this softening of sediments. 'Decompaction' of the core reconstruction with this modified model accounted for the difference between the two RSL reconstructions. Our results demonstrate that compression-only geotechnical models may be inadequate for estimating compaction and post-depositional lowering of susceptible organic salt-marsh sediments in some settings. This has important implications for our understanding of the drivers of sea-level change. Further, our results suggest that future climate changes may make salt

Degradation of wall paints due to sodium sulphate and sodium chloride crystallization

Directory of Open Access Journals (Sweden)

Díaz Gonçalves, T.

2003-03-01

Full Text Available A test method for evaluating wall paints behaviour to soluble salts crystallization was developed at LNEC. in the present paper, a recent set of tests is described and discussed. The major objectives were: analysing and comparing the behaviour of a common emulsion {"plastic" paint and a silicate-based paint; observing and comparing the effect of sodium sulphate, sodium chloride and distilled water on the paints and on a non-painted stone; evaluating this test method adequacy and effectiveness. The silicate-based paint showed a resistance to soluble salts crystallization greater than the one of the plastic paint. However, the degradation pattern of the silicate-based paint (blistering of a filmic layer was similar to the one of organic paints and distinct from the one of pure mineral paints. The amount of damage that a saline solution can cause to wall paints cannot be inferred from the amount of damage it can cause to stone. Sodium chloride seems to be able to cause more severe degradation to wall paints than sodium sulphate. To the unpainted stone, sodium sulphate seems to be more damaging than sodium chloride. The test method seems adequate to observe and compare the behaviour of wall paints under soluble salts action. However, lower (around 0.5% concentrations for both sodium sulphate and sodium chloride should be tested in the future.

RESUMEN En el LNEC se desarrolló una metodología de ensayo para evaluar la respuesta de pinturas aplicadas sobre paredes, frente a la cristalización de sales solubles. En este trabajo, se describen y discuten un conjunto de ensayos recientes. Los principales objetivos fueron: el análisis y la comparación del comportamiento de una pintura de emulsión común {''pintura plástica" y la de una pintura de silicato; la observación y la comparación de los efectos del sulfato de sodio, del cloruro de sodio y del agua destilada sobre las pinturas y sobre piedra no pintada; la evaluación de la adecuaci

Salt sensitivity: a review with a focus on non-Hispanic blacks and Hispanics

Science.gov (United States)

Richardson, Safiya I.; Freedman, Barry I.; Ellison, David H.; Rodriguez, Carlos J.

2015-01-01

The purpose of this review is to summarize the available information regarding salt sensitivity particularly as it relates to non-Hispanic blacks and Hispanics and to clarify possible etiologies, especially those that might shed light on potential treatment options. In non-Hispanic blacks, there is evidence that endothelial dysfunction, reduced potassium intake, decreased urinary kallikrein excretion, upregulation of sodium channel activity, dysfunction in atrial natriuretic peptide (ANP) production, and APOL1 gene nephropathy risk variants may cause or contribute to salt sensitivity. Supported treatment avenues include diets high in potassium and soybean protein, the components of which stimulate nitric oxide production. Racial heterogeneity complicates the study of salt sensitivity in Hispanic populations. Caribbean Hispanics, who have a higher proportion of African ancestry, may respond to commonly prescribed anti-hypertensive agents in a way that is characteristic of non-Hispanic black hypertensives. The low-renin hypertensive phenotype commonly seen in non-Hispanic blacks has been linked to salt sensitivity and may indicate an increased risk for salt sensitivity in a portion of the Hispanic population. In conclusion, increased morbidity and mortality associated with salt sensitivity mandates further studies evaluating the efficacy of tailored dietary and pharmacologic treatment in non-Hispanic blacks and determining the prevalence of low renin hypertension and salt sensitivity within the various subgroups of Hispanic Americans. PMID:23428408

The street children of Manila are affected by early-in-life periodontal infection: description of a treatment modality: sea salt.

Science.gov (United States)

Michel, J F; Michel, M G; Nadan, J; Nowzari, H

2013-01-01

Thousands of street children of Manila are affected by early-in-life oral infection. The aim of the present investigation was to evaluate the effectiveness of a sea-salt mouthrinse solution in street children of Manila affected by mild to severe forms of periodontal disease. These children were all in need of special protection: abandoned, abused, exploited, neglected, orphaned, poor. During 3 oral-health missions in 2003, 2004 and 2005, 617 abandoned children (5 to 13 year-old), received oral examination at a non-sectarian child-caring institution in Metro Manila (Virlanie Foundation) by calibrated examiners. A treatment based on what could be done was proposed: 1. Teaching of a precise tooth brushing technique with sea-salt, controlled and reinforced every two days for one week by calibrated health educators, 2. The application of sea-salt water mouthrinse (2.5 gram in 20 ml). Periodontal measurements were repeated at the end of each mission. All children returned to child-caring institution for the followup examinations. In 2003, 10 male and 11 female (n=21) were diagnosed with aggressive periodontitis. In 2009 and 2010, none was affected by aggressive periodontitis. For all patients, the gingival index decreased from 1.08 at the first mission to 1.04 at the end of the second mission and 0.98 at the end of the third mission. The periodontal index decreased from 1.33 at the first mission to 0.98 at the second mission and 0.92 at the last mission. The present investigation confirms that prevention and early diagnosis can result in success with minimum cost. The provided oral health program empowered street children in the most desperate circumstances to be educated and become self-reliant, independent, and responsible. We propose here an antimicrobial approach which has a high degree of efficacy and tolerability, and can be implemented in virtually all parts of the world using low-cost resources.

Thermodynamic analysis of dust sulphation reactions

Energy Technology Data Exchange (ETDEWEB)

Yang Yongxiang; Jokilaakso, A.

1997-12-31

Sulphation reactions of metal oxides with SO{sub 2} and O. or SO{sub 3} play significant roles in sulphation roasting of sulphide and oxide minerals as well as in desulphurisation process of combustion gases. In metallurgical waste-heat boilers for sulphide smelting, the sulphation of the oxidic flue dust in the atmosphere containing sulphur oxides is an unavoidable process, and the sulphation reactions have to be guided in a controlled way in the proper parts of the gas handling equipment. In this report, some thermodynamic analyses were conducted for the oxide sulphation reactions in relation to sulphide smelting processes. The phase stability of Me-S-O systems especially for oxides - sulphates equilibrium was studied under different thermodynamic conditions of gas compositions and temperatures. The sulphate stability was analysed for an example of gas compositions in the copper flash smelter of Outokumpu Harjavalta Metals Oy, in relation to temperature. In the report, most of the information was from literature. Moreover, a number of thermodynamic computations were carried out with the HSC program, and the constructed phase stability diagrams were compared with those from the literature whenever possible. The maximum temperatures for stable sulphates under normal operating conditions of the waste-heat boilers in sulphide smelting processes were obtained. This report will serve as the basis for the kinetic studies of the sulphation reactions and the sulphation reaction modelling in pyrometallurgical processes. (orig.) SULA 2 Programme. 36 refs.

A sulphated flavone glycoside from Livistona australis and its antioxidant and cytotoxic activity.

Science.gov (United States)

Kassem, Mona E S; Shoela, Soha; Marzouk, Mona M; Sleem, Amany A

2012-01-01

A new flavone glycoside tricin 7-O-β-glucopyranoside-2″-sulphate sodium salt along with 14 known flavonoid compounds were isolated and identified from the aqueous methanol extract of Livistona australis leaves. Their structures were established on the basis of extensive NMR (¹H, ¹³C, HSQC and H-H COSY) and ESIMS data. Antioxidant and cytotoxicity properties of the methanol extract of the leaves as well as the new compound were investigated.

The microbial communities and potential greenhouse gas production in boreal acid sulphate, non-acid sulphate, and reedy sulphidic soils

Czech Academy of Sciences Publication Activity Database

Šimek, Miloslav; Virtanen, S.; Simojoki, A.; Chroňáková, Alica; Elhottová, Dana; Krištůfek, Václav; Yli-Halla, M.

2014-01-01

Roč. 466, January (2014), s. 663-672 ISSN 0048-9697 R&D Projects: GA ČR GA526/09/1570; GA MŠk LC06066 Grant - others:GAJU(CZ) GAJU 138/2010/P Institutional support: RVO:60077344 Keywords : acid sulphate soil * carbon * CARD-FISH * microorganisms * nitrogen * PLFA Subject RIV: EE - Microbiology, Virology Impact factor: 4.099, year: 2014

Simulating emission and chemical evolution of coarse sea-salt particles in the Community Multiscale Air Quality (CMAQ model

Directory of Open Access Journals (Sweden)

J. T. Kelly

2010-04-01

Full Text Available Chemical processing of sea-salt particles in coastal environments significantly impacts concentrations of particle components and gas-phase species and has implications for human exposure to particulate matter and nitrogen deposition to sensitive ecosystems. Emission of sea-salt particles from the coastal surf zone is known to be elevated compared to that from the open ocean. Despite the importance of sea-salt emissions and chemical processing, the US EPA's Community Multiscale Air Quality (CMAQ model has traditionally treated coarse sea-salt particles as chemically inert and has not accounted for enhanced surf-zone emissions. In this article, updates to CMAQ are described that enhance sea-salt emissions from the coastal surf zone and allow dynamic transfer of HNO₃, H₂SO₄, HCl, and NH₃ between coarse particles and the gas phase. Predictions of updated CMAQ models and the previous release version, CMAQv4.6, are evaluated using observations from three coastal sites during the Bay Regional Atmospheric Chemistry Experiment (BRACE in Tampa, FL in May 2002. Model updates improve predictions of NO₃⁻, SO₄²⁻, NH₄⁺, Na⁺, and Cl⁻ concentrations at these sites with only a 8% increase in run time. In particular, the chemically interactive coarse particle mode dramatically improves predictions of nitrate concentration and size distributions as well as the fraction of total nitrate in the particle phase. Also, the surf-zone emission parameterization improves predictions of total sodium and chloride concentration. Results of a separate study indicate that the model updates reduce the mean absolute error of nitrate predictions at coastal CASTNET and SEARCH sites in the eastern US. Although the new model features improve performance relative to CMAQv4.6, some persistent differences exist between observations and predictions

Estimates of future inundation of salt marshes in response to sea-level rise in and around Acadia National Park, Maine

Science.gov (United States)

Nielsen, Martha G.; Dudley, Robert W.

2013-01-01

Salt marshes are ecosystems that provide many important ecological functions in the Gulf of Maine. The U.S. Geological Survey investigated salt marshes in and around Acadia National Park from Penobscot Bay to the Schoodic Peninsula to map the potential for landward migration of marshes using a static inundation model of a sea-level rise scenario of 60 centimeters (cm; 2 feet). The resulting inundation contours can be used by resource managers to proactively adapt to sea-level rise by identifying and targeting low-lying coastal areas adjacent to salt marshes for conservation or further investigation, and to identify risks to infrastructure in the coastal zone. For this study, the mapping of static inundation was based on digital elevation models derived from light detection and ranging (LiDAR) topographic data collected in October 2010. Land-surveyed control points were used to evaluate the accuracy of the LiDAR data in the study area, yielding a root mean square error of 11.3 cm. An independent accuracy assessment of the LiDAR data specific to salt-marsh land surfaces indicated a root mean square error of 13.3 cm and 95-percent confidence interval of ± 26.0 cm. LiDAR-derived digital elevation models and digital color aerial photography, taken during low tide conditions in 2008, with a pixel resolution of 0.5 meters, were used to identify the highest elevation of the land surface at each salt marsh in the study area. Inundation contours for 60-cm of sea-level rise were delineated above the highest marsh elevation for each marsh. Confidence interval contours (95-percent,± 26.0 cm) were delineated above and below the 60-cm inundation contours, and artificial structures, such as roads and bridges, that may present barriers to salt-marsh migration were mapped. This study delineated 114 salt marshes totaling 340 hectares (ha), ranging in size from 0.11 ha (marshes less than 0.2 ha were mapped only if they were on Acadia National Park property) to 52 ha, with a median

Grazing management can counteract the impacts of climate change-induced sea level rise on salt marsh-dependent waterbirds

DEFF Research Database (Denmark)

Clausen, Kevin Kuhlmann; Stjernholm, Michael; Clausen, Preben

2013-01-01

with these changes. In addition, we quantify the areal extent of inadequate salt marsh management in four EU Special Protection Areas for Birds, and demonstrate concurrent population dynamics in four species relying on managed habitats. We conclude by investigating potential compensation for climate change......1) Climate change–induced rises in sea level threaten to drastically reduce the areal extent of important salt marsh habitats for large numbers of waterfowl and waders. Furthermore, recent changes in management practice have rendered existent salt marshes unfavourable to many birds, as lack...... (around 1 cow per hectare) is an important initiative to counteract the accelerating climate change–induced habitat loss in near-coastal areas across the globe, and to secure priority salt marsh habitats that support internationally important populations of breeding, wintering and staging waterfowl...

The influence of brown coal exploitation in Poland on the groundwater pollution as determined by isotopic analyses of sulphate

International Nuclear Information System (INIS)

Halas, S.; Trembaczowski, A.; Soltyk, W.

1998-01-01

This research deals with pollution impact on natural water resources in the industrial area of Belchatow, central Poland, where a large brown coal deposit is exploited and the coal is burned in an electric power plant. To trace the sources of groundwater pollutants the stable isotope analysis of oxygen and sulphur in sulphates was applied. The mass-spectrometric analysis was performed on SO 4 2- samples from numerous wells and piezometres in the excavation area. By repetitive sampling performed in November 1994, May 1995 and December 1996 significant changes of SO 4 2- concentration and sulphur and oxygen isotopic ratios in several sites were recorded. The interpretation of isotope ratios allowed us to recognize three groups of sulphates: (1) from the leaching of Permian salt dome, (2) produced by the leaching of soluble sulphates from an ash pool and (3) produced by oxidation of natural sulphides in water-bearing rocks. (author)

In vitro studies on interactions of iron salts and complexes with food-stuffs and medicaments.

Science.gov (United States)

Geisser, P

1990-07-01

It has been shown in the present study that food components such as phytic acid, oxalic acid, tannin, sodium alginate, choline and choline salts, vitamins A, D3 and E, soy oil and soy flour, do not undergo any interactions with iron(III)-hydroxide polymaltose complex (Ferrum Hausmann). Phytic acid, oxalic acid, tannin and sodium alginate, however, react with iron(II) or iron(III)-salts at pH values of 3.0, 5.5 and 8.0, giving rise to iron complexes. Trimethylamine-N-oxide, which is present in fish meal, reacts with iron(II)-sulphate to produce iron(III) reaction products; it does not react with iron(III)-hydroxide polymaltose complex. Special soybean flours show no irreversible adsorption or precipitation with iron(III)-hydroxyide polymaltose complex over the pH range 3.0-8.0, in contrast to iron(II)-sulphate. Antacids containing aluminium hydroxide, talc, ion exchange resins or other unabsorbable, insoluble components absorb iron(III)-hydroxide polymaltose complex in the pH range 3.0-8.0 in a reversible manner, while the strong adsorption or precipitation observed with iron(II)-sulphate at pH 8.0 is irreversible. No interaction was observed between the steroid hormones studied and iron(II)-sulphate or iron(III)-hydroxide polymaltose complex. On the basis of the measured compatibilities, iron(III)-hydroxide polymaltose complex can be administered orally simultaneously with many other drugs, without prejudicing the absorption of iron or of the other drug as is often seen with iron(II) and iron(III) salts.

Development of a technique for mass spectrometric measurement of δ18O of aqueous sulphate

International Nuclear Information System (INIS)

Kulkarni, U.P.; Sharma, Suman

2003-01-01

Application of stable isotopes of hydrogen and oxygen as tracers in hydrology for studying the origin of water is well established. δ 18 O of water molecule itself is used for identifying the source of water whereas δ 18 O of dissolved oxy anions (such as carbonate, phosphate, sulphate, nitrate and silicate) present in the same water reveal their source of origin. δ 18 O of SO 4 finds applications in identifying the origin of sulfate i.e. marine, marine evaporite or non-marine in nature and as a geothermometer in determining subsurface temperature of geothermal waters. A vacuum line of glass was fabricated to measure δ 18 O of aqueous sulfate. This paper deals with the technique and results of a trial with NBS-127, Sea water barium sulfate

Copper sulphate poisoning in horses

Energy Technology Data Exchange (ETDEWEB)

Bauer, M

1975-01-01

In the archives of the Clinic for Internal Diseases of Domestic Animals at the Veterinary Faculty of Zagreb University some thirty cases of horse disease diagnosed as copper sulphate poisoning were noted. The data correspond in many respects to the clinical findings of copper sulphate poisoning in other domestic animals. A series of experimental horse poisonings were undertaken in order to determine the toxicity of copper sulphate. The research results are as follows: Horses are sensitive to copper sulphate. Even a single application of 0.125 g/kg body weight in 1% concentration by means of incubation into the stomach causes stomach and gut disturbances and other poisoning symptoms. Poisoning occurs in two types: acute and chronic. The former appears after one to three applications of copper sulphate solution and is characterized by gastroenteritis, haemolysis, jaundice and haemoglobinuria with signs of consecutive damage of kidney, liver and other organs. The disease, from the first application to death lasts for two weeks. Chronic poisoning is caused by ingestion of dry copper sulphate in food (1% solution dried on hay or clover) for two or more months. There are chronic disturbances of stomach and gut and loss of weight, and consecutive (three to four) haemolytic crises similar to those of acute poisoning. From the beginning of poisoning to death six or more months can elapse.

Reuse of Partially Sulphated CFBC Ash as an SO2 Sorbent

Energy Technology Data Exchange (ETDEWEB)

Wu, Yinghai; Jia, Lufei; Anthony, E.J. [CanmetENERGY, 1 Haanel Drive, Ottawa, Ontario, K1A1M1 (Canada); Nobili, M.; Telesca, A. [Department of Environmental Engineering and Physics, University of Basilicata, Viale dell' Ateneo, Lucano 10, 85100 Potenza (Italy); Montagnaro, F. [Department of Chemistry, University of Naples ' Federico II' , Monte Sant' Angelo, 80126 Naples (Italy)

2010-06-15

Ashes produced from fluidized bed combustors (FBC) burning high-sulphur fuels often contain 20-30 % unreacted CaO because of the limestone added to remove SO2 in situ. This paper presents the results from experiments into reactivating partially sulphated FBC ash (both bed ash and fly ash) with liquid water, steam and sodium carbonate. The water- or steam-hydrated ashes were subsequently re-sulphated in a thermogravimetric analyzer (TGA) with simulated flue gas. The TGA results show that, while liquid water and steam successfully hydrate and reactivate the unreacted CaO in the bed ash, the treated ashes sulphated to widely different extents. Attempts to reactivate fly ash with hydration failed, although fly ash by itself is extremely reactive. A pilot-scale mini-circulating FBC (CFBC) was also used to evaluate the results of reactivation on the bed ash by hydrating with liquid water and admixtures of inorganic salt (Na2CO3) in the form of either powder or solution. When the treated ash was re-injected into the combustor with the fuel, the effect on SO2 removal efficiency was negligible if Na2CO3 was added as powder. Doping with aqueous solution resulted in enhanced SO2 removal; however, the extent was lower than the level achieved if only water hydration was employed. Increasing the amount of water (from 10% to 30%) to reactivate the ash did not improve the sulphur capture capacity in the mini-CFBC. Overall, this study suggests that the most practical way for re-use of the partially sulphated bed ash as a sulphur sorbent is reactivation by water. A proposal for utilization of the fly ash in an economically reasonable way is also discussed.

Kinetics of barium sulphate reaction crystallization in crystallizers with internal circulation

Directory of Open Access Journals (Sweden)

J. Koralewska

2008-06-01

Full Text Available Kinetic calculation results describing the observed nucleation and growth rates of barium sulphate crystals precipitated in an integrated reaction-crystallization process in a barium sulphate-ammonium chloride-water system are presented and analyzed. The scope of experiments included two continuous model DTM-type crystallizers (Draft Tube Magma with internal circulation of the suspension forced by a liquid jet-pump device responsible for stable and intensive enough ascending/descending flow of BaSO4 crystal magma in a mixing chamber. For comparison purposes the experimental data corresponding to a continuous DT (Draft Tube crystallizer with propeller agitator are presented and discussed. The various types of laboratory crystallizers used were fed with concentrated water solution of barium chloride (of 10 or 24 mass % and - in a stoichiometric proportion - crystalline ammonium sulphate, assuming isothermal (348 K and hydrodynamic (average residence time of suspension in a crystallizer: 900 s process conditions. The observed nucleation and growth rates of barium sulphate crystals were estimated on the basis of crystal size distributions (CSDs using convenient calculation scheme derived for an MSMPR (Mixed Suspension Mixed Product Removal model approach. Considering the experimental population density distribution courses, a size-dependent growth (SDG phenomenon was taken into account in the kinetic calculations. Five SDG kinetic models recommended in the accessible literature were used for kinetic parameter values estimation. It was proved statistically, that Rojkowski’s two SDG models (hyperbolic and exponential best suit for our own experimental data description. The experimental data presented can be practically applied for improving the constructions of liquid jet-pump DTM crystallizers recommended for reaction crystallization of sparingly soluble inorganic salts (especially for high concentrations of reaction substrates in the modern

Landscape Changes and a Salt Production Sustainable Approach in the State of Salt Pan Area Decreasing on the Coast of Tianjin, China

Directory of Open Access Journals (Sweden)

Hui Wang

2015-07-01

Full Text Available Landsat images from 1979, 1988, 1999, 2008, and 2013 were used to analyze the landscape area change of salt pans lying on the coast of Tianjin. While initially (1979–1988, the area of Tianjin’s salt pan increased, later (1988–2013 it declined dramatically. In the first phase (1979–1988 of the studied period the primary roll-in landscape of the salt pan wasbarren land with an area of 60.0 km2. By 1988, the area of Tianjin’s salt pan rose to 457.8 km2. The main roll-out landscape of the salt pan during 1988–2013 was urban, barren land, village/town, harbor, and road whose area amounted to 69.8, 35.9, 27.3, 25.5 and 18.4 km2 respectively. The roll-out barren land will be transformed to construction land ultimately. By 2013, the total loss reached 167.3 km2, which was 36.5% of the salt pan area of Tianjin in 1988. With the development of coastal economy, the salterns with a lower economic value were transformed to and replaced by land use types with a higher economic value. This trend would influence the production of sea salt and the development of sodium hydroxide and sodium carbonate industries. Seawater desalination provides an opportunity for the restoration and compensation of salt production capacity. Based on the theory of circular economy and industrial symbiosis, in this article an industrial symbiosis model for sea salt production and sea water desalination is explored: “mariculture–power plant cooling–seawater desalination–Artemia culture–bromide extraction–sea salt production–salt chemical industry”. Through the application of this process sustainable development of the sea salt production in Tianjin could be achieved.

The microbial communities and potential greenhouse gas production in boreal acid sulphate, non-acid sulphate, and reedy sulphidic soils.

Science.gov (United States)

Šimek, Miloslav; Virtanen, Seija; Simojoki, Asko; Chroňáková, Alica; Elhottová, Dana; Krištůfek, Václav; Yli-Halla, Markku

2014-01-01

Acid sulphate (AS) soils along the Baltic coasts contain significant amounts of organic carbon and nitrogen in their subsoils. The abundance, composition, and activity of microbial communities throughout the AS soil profile were analysed. The data from a drained AS soil were compared with those from a drained non-AS soil and a pristine wetland soil from the same region. Moreover, the potential production of methane, carbon dioxide, and nitrous oxide from the soils was determined under laboratory conditions. Direct microscopic counting, glucose-induced respiration (GIR), whole cell hybridisation, and extended phospholipid fatty acid (PLFA) analysis confirmed the presence of abundant microbial communities in the topsoil and also in the deepest Cg2 horizon of the AS soil. The patterns of microbial counts, biomass and activity in the profile of the AS soil and partly also in the non-AS soil therefore differed from the general tendency of gradual decreases in soil profiles. High respiration in the deepest Cg2 horizon of the AS soil (5.66 μg Cg(-1)h(-1), as compared to 2.71 μg Cg(-1)h(-1) in a top Ap horizon) is unusual but reasonable given the large amount of organic carbon in this horizon. Nitrous oxide production peaked in the BCgc horizon of the AS and in the BC horizon of the non-AS soil, but the peak value was ten-fold higher in the AS soil than in the non-AS soil (82.3 vs. 8.6 ng Ng(-1)d(-1)). The data suggest that boreal AS soils on the Baltic coast contain high microbial abundance and activity. This, together with the abundant carbon and total and mineral nitrogen in the deep layers of AS soils, may result in substantial gas production. Consequently, high GHG emissions could occur, for example, when the generally high water table is lowered because of arable farming. © 2013.

Mobilization of arsenic, lead, and mercury under conditions of sea water intrusion and road deicing salt application

Science.gov (United States)

Sun, Hongbing; Alexander, John; Gove, Brita; Koch, Manfred

2015-09-01

Water geochemistry data from complexly designed salt-solution injection experiments in the laboratory, coastal aquifers of Bangladesh and Italy, taken from the literature, and two salted watersheds of New Jersey, US were collected and analyzed to study the geochemical mechanisms that mobilize As, Pb, and Hg under varied salting conditions. Overall, increased NaCl-concentrations in aquifers and soil are found to increase the release of Pb and Hg into the water. Reducing environments and possible soil dispersion by hydrated Na+ are found to lead to an increase of As-concentration in water. However, the application of a pure NaCl salt solution in the column injection experiment was found to release less As, Pb, and Hg initially from the soil and delay their concentration increase, when compared to the application of CaCl2 and NaCl mixed salts (at 6:4 weight ratio). The concentration correlation dendrogram statistical analyses of the experimental and field data suggest that the release of As, Hg, and Pb into groundwater and the soil solution depends not only on the salt level and content, but also on the redox condition, dissolved organic matter contents, competitiveness of other ions for exchange sites, and source minerals. With the ongoing over-exploration of coastal aquifers from increased pumping, continued sea-level rise, and increased winter deicing salt applications in salted watersheds of many inland regions, the results of this study will help understand the complex relation between the concentrations of As, Pb, and Hg and increased salt level in a coastal aquifer and in soils of a salted watershed.

Sulphation of calcium-based sorbents in circulating fluidised beds under oxy-fuel combustion conditions

Energy Technology Data Exchange (ETDEWEB)

Francisco Garcia-Labiano; Luis F. de Diego; Alberto Abad; Pilar Gayan; Margarita de las Obras-Loscertales; Aranzazu Rufas; Juan Adanez [Instituto de Carboquimica (CSIC), Zaragoza (Spain). Dept. Energy and Environment

2009-07-01

Sulphur Retention (SR) by calcium-based sorbents is a process highly dependent on the temperature and CO{sub 2} concentration. In circulating fluidised beds combustors (CFBC's) operating under oxy-fuel conditions, the sulphation process takes place in atmospheres enriched in CO{sub 2} with bed concentrations that can vary from 40 to 95%. Under so high CO{sub 2} concentrations, very different from that in conventional coal combustion atmosphere with air, the calcination and sulphation behaviour of the sorbent must be defined to optimise the SR process in the combustor. The objective of this work was to determine the SO{sub 2} retention capacity of a Spanish limestone at typical oxy-fuel conditions in CFBC's. Long term duration tests of sulphation (up to 24 h), to simulate the residence time of sorbents in CFBC's, were carried out by thermogravimetric analysis (TGA). Clear behaviour differences were found under calcining and non-calcining conditions. Especially relevant was the result obtained at calcining conditions but close to the thermodynamic temperature given for sorbent calcination. This situation must be avoided in CFBC's because the CO{sub 2} produced inside the particle during calcination can destroy the particles if a non-porous sulphate product layer has been formed around the particle. The effect of the main variables on the sorbent sulphation such as SO{sub 2} concentration, temperature, and particle size were analysed in the long term TGA tests. These data were also used to determine the kinetic parameters for the sulphation under oxy-fuel combustion conditions, which were able to adequately predict the sulphation conversion values in a wide range of operating conditions. 20 refs., 5 figs., 2 tabs.

Radioprotective effects of dextran sulphate in mice

International Nuclear Information System (INIS)

Vacek, A.; Bartonickova, A.; Rotkovska, D.; Palyga, G.F.; Zhukova, N.A.

1981-01-01

Influence of a single i.p. injection of dextran sulphate on radiosensitivity of mice was investigated. The administration of dextran sulphate 24, 48 and 72 hours prior to irradiation increased formation of endogenous colonies of the hemopoietic tissue on the surface of the spleen. DRF calculated from an equieffective exposure for 5 colonies was 1.96 when dextran sulphate was administered 24 hours before irradiation, and 2.25 when dextran sulphate was administered 72 hours before irradiation. The radioprotective effects of dextran sulphate were manifested also in the survival of animals exposed to lethal doses of short-termed as well as long-termed gamma radiation. (orig.) [de

Profiles of bile acids and their glucuronide and sulphate conjugates in the serum, urine and bile from patients undergoing bile drainage.

OpenAIRE

Takikawa, H; Beppu, T; Seyama, Y

1985-01-01

Bile acid profiles in serum, urine, and bile from patients undergoing bile drainage and the changes of serum bile acids after bile drainage were studied. Bile acids were separated into non-glucuronidate-non-sulphate, glucuronidated, and sulphated fractions and were measured by mass fragmentography using conjugates of deuterium labelled bile acids as internal standards. Glucuronidated and sulphated bile acids contribute 14-32% and 16-44% of serum bile acids, 4-11% and 61-82% of urine bile acid...

Sulphate solubility and sulphate diffusion in oxide glasses: implications for the containment of sulphate-bearing nuclear wastes; Solubilite et cinetiques de diffusion des sulfates dans differents verres d'oxydes: application au conditionnement des dechets nucleaires sulfates

Energy Technology Data Exchange (ETDEWEB)

Lenoir, M.

2009-09-15

The thesis deals with sulphate solubility and sulphate diffusion in oxide glasses, in order to control sulphate incorporation and sulphate volatilization in nuclear waste glasses. It was conducted on simplified compositions, in the SiO{sub 2}-B{sub 2}O{sub 3}-R{sub 2}O (R = Li, Na, K, Cs), SiO{sub 2}-B{sub 2}O{sub 3}-BaO and V{sub 2}O{sub 5}-B{sub 2}O{sub 3}-BaO systems. These compositions allowed us to study the influence of the nature of network-modifying ions (Li{sup +}, Na{sup +}, K{sup +}, Cs{sup +} or Ba{sup 2+}) and also of former elements (Si, B, V), on structure and properties of glasses. Sulphate volatility is studied in sodium borosilicate melts using an innovative technique of sulphate quantitation with Raman spectroscopy. This technique is useful to obtain kinetic curves of sulphate volatilization. The establishment of a model to fit these curves leads to the determination of diffusion coefficients of sulphate. These diffusion coefficients can thus be compared to diffusion coefficients of other species, determined by other techniques and presented in the literature. They are also linked to diffusion coefficients in relation with the viscosity of the melts. Concerning sulphate solubility in glasses, it depends on glass composition and on the nature of sulphate incorporated. Sulphate incorporation in alkali borosilicate glasses leads to the formation of a sulphate layer floating on top of the melt. Sulphate incorporation in barium borosilicate and boro-vanadate glasses leads to the crystallization of sulphate species inside the vitreous matrix. Moreover, sulphate solubility is higher in these glasses than in alkali borosilicates. Finally, exchanges between cations present in glasses and cations present in the sulphate phase are also studied. (author)

The application of the acoustic emission technique to stone decay by sodium sulphate in laboratory tests

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Grossi, C. M.

1997-03-01

Full Text Available Acoustic emission was monitored during salt crystallisation cycles in order to study the mechanisms of rock deterioration by sodium sulphate in laboratory tests. Some porous carbonate stones used in Spanish monuments (Cathedral of Oviedo, Murcia and Seo Vella of Lérida were selected for this study. The acoustic emission detected during the different stages of the cycles (immersion, drying and cooling was interpreted to be the result of the salt behaviour inside the stone. The use of this technique has confirmed that this behaviour depends on salt characteristics (solubility, hydration state and polymorphism of anhydrous sodium sulphate and stone porosity and pore network.

Para determinar los mecanismos de deterioro de las rocas debidos a la acción del sulfato de sodio, se ha registrado la emisión acústica durante ensayos de cristalización de sales en el laboratorio. Para ello, se han seleccionado tres piedras porosas carbonatadas utilizadas como materiales de construcción en monumentos españoles (Catedrales de Oviedo, Murcia y Seo Vella de Lérida. La emisión acústica detectada durante las diferentes etapas de los ciclos (inmersión, secado y enfriamiento se ha interpretado como debida al comportamiento de la sal en el interior de la piedra. Mediante esta técnica se ha confirmado que este comportamiento depende de las características de la sal (solubilidad, diferentes estados de hidratación y el polimorfismo del sulfato de sodio anhidro y de la porosidad y configuración del sistema poroso de las rocas.

Corrosion behaviour of non-ferrous metals in sea water

Energy Technology Data Exchange (ETDEWEB)

Birn, Jerzy; Skalski, Igor [Ship Design and Research Centre, Al. Rzeczypospolitej 8, 80-369 Gdansk (Poland)

2004-07-01

The most typical kinds of corrosion of brasses are selective corrosion (dezincification) and stress corrosion. Prevention against these kinds of corrosion lies in application of arsenic alloy addition and appropriate heat treatment removing internal stresses as well as in maintaining the arsenic and phosphorus contents on a proper level. The most typical corrosion of cupronickels is the local corrosion. Selective corrosion occurs less often and corrosion cracking caused by stress corrosion in sea water does not usually occur. Crevice corrosion is found especially in places of an heterogeneous oxidation of the surface under inorganic deposits or under bio-film. Common corrosive phenomena for brasses and cupronickels are the effects caused by sea water flow and most often the impingement attack. Alloy additions improve resistance to the action of intensive sea water flow but situation in this field requires further improvement, especially if the cheaper kinds of alloys are concerned. Contaminants of sea water such as ammonia and hydrogen sulphide are also the cause of common corrosion processes for all copper alloys. Corrosion of copper alloys may be caused also by sulphate reducing bacteria (SRB). Galvanic corrosion caused by a contact with titanium alloys e.g. in plate heat exchangers may cause corrosion of both kinds copper alloys. Bronzes belong to copper alloys of the highest corrosion resistance. Failures that sometimes occur are caused most often by the cavitation erosion, by an incorrect chemical composition of alloys or at last by their inadequate structure. The main problems of aluminium alloys service in sea water are following phenomena: local corrosion (pitting and crevice corrosion), galvanic corrosion, exfoliation and corrosion in the presence of OH- ions. The cause of local corrosion are caused by presence of passive film on the alloy's surface and presence of chlorides in sea water which are able to damage the passive film. Galvanic corrosion is

Non-Catalytic and MgSO4 - Catalyst based Degradation of Glycerol in Subcritical and Supercritical Water Media

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Mahfud Mahfud

2011-02-01

Full Text Available This research aims to study the glycerol degradation reaction in subcritical and supercritical water media. The degradation of glycerol into other products was performed both with sulphate salt catalysts and without catalyst. The reactant was made from glycerol and water with the mass ratio of 1:10. The experiments were carried out using a batch reactor at a constant pressure of 250 kgf/cm2, with the temperature range of 200-400oC, reaction time of 30 minutes, and catalyst mol ratio in glycerol of 1:10 and 1:8. The products of the non-catalytic glycerol degradation were acetaldehyde, methanol, and ethanol. The use of sulphate salt as catalyst has high selectivity to acetaldehyde and still allows the formation alcohol product in small quantities. The mechanism of ionic reaction and free radical reaction can occur at lower temperature in hydrothermal area or subcritical water. Conversion of glycerol on catalytic reaction showed a higher yield when compared with the reaction performed without catalyst

Assessment and Comparison of salt Content in Mangrove Plants in Sri Lanka

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N. P. Dissanayake

2009-09-01

Full Text Available Due to the predicted threats of global warming and sea level rise, the salt tolerance and salt accumulative abilities of plants have become popular contentious topics. Mangroves are one of the major groups of salt tolerant plants and several mechanisms are known as instrumental in their salt tolerance. Salt excretion through leaf drop is given as one, but its validity is questioned by some recent works compelling the necessity for further studies. Knowledge of the salt contents in different mangrove plants is a pre requisite for such studies. Hence, this study aimed to quantify and compare the salt content in mature leaves of nine mangrove species in Sri Lanka., i.e. Aegiceras corniculatum, Avicennia marina, Avicennia officinalis, Bruguiera gymnorrhiza, Bruguiera sexangula, Ceriops tagal, Excoecaria agallocha, Lumnitzera racemosa, Rhizophora apiculata and Rhizophora mucronata which are growing in the same mangrove system; the Rekawa lagoon in Sri Lanka. Two species of non mangrove plants, Gliricidia sepium and Artocarpus heterophyllus, which were growing in inland areas were also selected for comparison. The concentration of Na+ in leaves was considered as a measure of the salt concentration. The Na+ in leaves was extracted by acid digestion and quantified by flame photometry. The salt content of mangroves was measured under two contrasting hydrological situations: at the highest and lowest water levels of the lagoon. Rekawa lagoon can be considered as a ‘barrier built estuary’, the highest water level occurs when the lagoon mouth is blocked due to the formation of the sand bar and the water level is increased by fresh water inflow, inundating the total mangrove area and decreasing the soil/water salinity. The water level of the lagoon becomes lowest when the lagoon mouth is opened (naturally or by dredging and lagoon water is flushed out to the sea. Then the salinity of lagoon water becomes high due to sea water influx. The results showed

A non-multimacrocyclic heteroditopic receptor that cooperatively binds and effectively extracts KAcO salt.

Science.gov (United States)

Zakrzewski, Maciej; Kwietniewska, Natalia; Walczak, Wojciech; Piątek, Piotr

2018-06-06

Prepared in only three synthetic steps, a non-multimacrocyclic heteroditopic receptor binds potassium salts of halides and carboxylates with unusually high cooperativity, suggesting salt binding as associated ion-pairs. Unprecedented extraction of highly hydrophilic KAcO salt from water to organic solution is also demonstrated.

A universal salt model based on under-ground precipitation of solid salts due to supercritical water `out-salting'

Science.gov (United States)

Rueslåtten, H.; Hovland, M. T.

2010-12-01

One of the common characteristics of planets Earth and Mars is that both host water (H2O) and large accumulations of salt. Whereas Earth’s surface-environment can be regarded as ‘water-friendly’ and ‘salt hostile’, the reverse can be said for the surface of Mars. This is because liquid water is stable on Earth, and the atmosphere transports humidity around the globe, whereas on planet Mars, liquid water is unstable, rendering the atmosphere dry and, therefore, ‘salt-friendly’. The riddle as to how the salt accumulated in various locations on those two planets, is one of long-lasting and great debate. The salt accumulations on Earth are traditionally termed ‘evaporites’, meaning that they formed as a consequence of the evaporation of large masses of seawater. How the accumulations on Mars formed is much harder to explain, as an ocean only existed briefly. Although water molecules and OH-groups may exist in abundance in bound form (crystal water, adsorbed water, etc.), the only place where free water is expected to be stable on Mars is within underground faults, fractures, and crevices. Here it likely occurs as brine or in the form of ice. Based on these conditions, a key to understanding the accumulation of large deposits of salt on both planets is linked to how brines behave in the subsurface when pressurized and heated beyond their supercritical point. At depths greater than about 3 km (P>300 bars) water will no longer boil in a steam phase. Rather, it becomes supercritical and will attain the phase of supercritical water vapor (SCRIW) with a specific gravity of typically 0.3 g/cm3. An important characteristic of SCRIW is its inability to dissolve the common sea salts. The salt dissolved in the brines will therefore precipitate as solid particles when brines (seawater on the Earth) move into the supercritical P&T-domain (T>400°C, P>300 bars). Numerical modeling of a hydrothermal system in the Atlantis II Deep of the Red Sea indicates that a

Comparison of the effects of the K(+)-channel openers cromakalim and minoxidil sulphate on vascular smooth muscle.

Science.gov (United States)

Wickenden, A. D.; Grimwood, S.; Grant, T. L.; Todd, M. H.

1991-01-01

1 The actions of the potassium channel openers, cromakalim and minoxidil sulphate, were compared in a range of isolated blood vessel preparations. 2 Cromakalim and minoxidil sulphate inhibited spontaneous mechanical activity of the guinea-pig portal vein and relaxed the noradrenaline precontracted rat aorta with similar potency. In contrast, minoxidil sulphate was less potent than cromakalim in inhibiting spontaneous activity in the rat portal vein and was essentially inactive in the noradrenaline precontracted rat mesenteric artery and rabbit aorta. 3 Minoxidil sulphate did not antagonize the effects of cromakalim in the rabbit aorta indicating it was not acting as a partial 'agonist'. 4 Charybdotoxin, noxiustoxin and rubidium failed to discriminate between cromakalim and minoxidil sulphate indicating that the apparently selective effects of minoxidil sulphate were not mediated by either Ca(2+)-activated potassium channels, delayed rectifiers or rubidium impermeable potassium channels. 5 Glibenclamide antagonized the effects of cromakalim in an apparently competitive manner whereas the effects of minoxidil sulphate were antagonized in a non-competitive manner. The involvement of subtypes of ATP-sensitive potassium channels is discussed. PMID:1878752

Community solar salt production in Goa, India.

Science.gov (United States)

Mani, Kabilan; Salgaonkar, Bhakti B; Das, Deepthi; Bragança, Judith M

2012-12-01

Traditional salt farming in Goa, India has been practised for the past 1,500 years by a few communities. Goa's riverine estuaries, easy access to sea water and favourable climatic conditions makes salt production attractive during summer. Salt produced through this natural evaporation process also played an important role in the economy of Goa even during the Portuguese rule as salt was the chief export commodity. In the past there were 36 villages involved in salt production, which is now reduced to 9. Low income, lack of skilled labour, competition from industrially produced salt, losses incurred on the yearly damage of embankments are the major reasons responsible for the reduction in the number of salt pans.Salt pans (Mithagar or Mithache agor) form a part of the reclaimed waterlogged khazan lands, which are also utilised for aquaculture, pisciculture and agriculture. Salt pans in Goa experience three phases namely, the ceased phase during monsoon period of June to October, preparatory phase from December to January, and salt harvesting phase, from February to June. After the monsoons, the salt pans are prepared manually for salt production. During high tide, an influx of sea water occurs, which enters the reservoir pans through sluice gates. The sea water after 1-2 days on attaining a salinity of approximately 5ºBé, is released into the evaporator pans and kept till it attains a salinity of 23 - 25ºBé. The brine is then released to crystallizer pans, where the salt crystallises out 25 - 27ºBé and is then harvested.Salt pans form a unique ecosystem where succession of different organisms with varying environmental conditions occurs. Organisms ranging from bacteria, archaea to fungi, algae, etc., are known to colonise salt pans and may influence the quality of salt produced.The aim of this review is to describe salt farming in Goa's history, importance of salt production as a community activity, traditional method of salt production and the biota

Modeling and Evaluation of the Global Sea-Salt Aerosol Distribution: Sensitivity to Emission Schemes and Resolution Effects at Coastal/Orographic Sites

Science.gov (United States)

Spada, M.; Jorba, O.; Perez Garcia-Pando, C.; Janjic, Z.; Baldasano, J. M.

2013-01-01

One of the major sources of uncertainty in model estimates of the global sea-salt aerosol distribution is the emission parameterization. We evaluate a new sea-salt aerosol life cycle module coupled to the online multi-scale chemical transport model NMMB/BSC-CTM. We compare 5 year global simulations using five state-of-the-art sea-salt open-ocean emission schemes with monthly averaged coarse aerosol optical depth (AOD) from selected AERONET sun photometers, surface concentration measurements from the University of Miami's Ocean Aerosol Network, and measurements from two NOAA/PMEL cruises (AEROINDOEX and ACE1). Model results are highly sensitive to the introduction of sea-surface-temperature (SST)-dependent emissions and to the accounting of spume particles production. Emission ranges from 3888 teragrams per year to 8114 teragrams per year, lifetime varies between 7.3 hours and 11.3 hours, and the average column mass load is between 5.0 teragrams and 7.2 teragrams. Coarse AOD is reproduced with an overall correlation of around 0.5 and with normalized biases ranging from +8.8 percent to +38.8 percent. Surface concentration is simulated with normalized biases ranging from minus 9.5 percent to plus 28 percent and the overall correlation is around 0.5. Our results indicate that SST-dependent emission schemes improve the overall model performance in reproducing surface concentrations. On the other hand, they lead to an overestimation of the coarse AOD at tropical latitudes, although it may be affected by uncertainties in the comparison due to the use of all-sky model AOD, the treatment of water uptake, deposition and optical properties in the model and/or an inaccurate size distribution at emission.

Removal of Sulphate and Manganese on Synthetic Wastewater in Sulphate Reducing Bioreactor Using Indonesian Natural Zeolite

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Endah Retnaningrum

2017-07-01

Full Text Available The present research was conducted to investigate sulphate and manganese removal from synthetic wastewater. The continuous laboratory scale of down-flow fluidized-bed reactor (DFBR using sulphate reducing bacteria (SRB consortium and Indonesian natural zeolite as a bacterial support material was designed. At 9 days operation, maximum sulphate and manganese removal was observed to be 23% and 15.4%, respectively. The pH values were also changed to neutral. The population of SRB increased which effect on the raising of their activity for removing sulphate and manganese. Using the scanning electronic microscopy (SEM, it was observed that natural zeolite possesses excellent physical characteristics as a bacterial support material in DFBR. The imaging SEM result of SRB consortium on zeolite surface clearly showed the developed SRB biofilm on that particle. Analysis result of EDX confirmed that manganese was precipitated as manganese–sulfides.

Risk minimisation of FGD gypsum leachates by incorporation of aluminium sulphate

Energy Technology Data Exchange (ETDEWEB)

Alvarez-Ayuso, E. [Department of Environmental Geology, Institute of Earth Sciences ' Jaume Almera' (CSIC), C/ Lluis Sole i Sabaris, s/n, 08028 Barcelona (Spain); Department of Environmental Geochemistry, IRNASA, CSIC, Apto. 257, 37071 Salamanca (Spain)], E-mail: ealvarez@ija.csic.es; Querol, X. [Department of Environmental Geology, Institute of Earth Sciences ' Jaume Almera' (CSIC), C/ Lluis Sole i Sabaris, s/n, 08028 Barcelona (Spain); Ballesteros, J.C.; Gimenez, A. [Endesa Generacion, S.A., C/ Ribera de Loira, 60, 28042 Madrid (Spain)

2008-11-15

The incorporation of aluminium sulphate to (flue gas desulphurisation) FGD gypsum before its disposal was investigated as a way to minimise the risk supposed by the high fluoride content of its leachates. Using a bath method the kinetic and equilibrium processes of fluoride removal by aluminium sulphate were studied at fluoride/aluminium molar concentration (F/Al) ratios in the range 1.75 10{sup -2}-1.75 under the pH conditions (about 6.5) of FGD gypsum leachates. It was found that fluoride removal was a very fast process at any of the (F/Al) ratios subject of study, with equilibrium attained within the first 15 min of interaction. High decreases in solution fluoride concentrations (50-80%) were found at the equilibrium state. The use of aluminium sulphate in the stabilization of FGD gypsum proved to greatly decrease its fluoride leachable content (in the range 20-90% for aluminium sulphate doses of 0.1-5%, as determined by the European standard EN 12457-4). Such fluoride leaching minimisation assures the characterization of this by-product as a waste acceptable at landfills for non-hazardous wastes according to the Council Decision 2003/33/EC on waste disposal. Furthermore, as derived from column leaching studies, the proposed stabilization system showed to be highly effective in simulated conditions of disposal, displaying fluoride leaching reduction values about 55 and 80% for aluminium sulphate added amounts of 1 and 2%, respectively.

Efficacy of a Rinse Containing Sea Salt and Lysozyme on Biofilm and Gingival Health in a Group of Young Adults: A Pilot Study

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Jeyaraj Hoover

2017-01-01

Full Text Available Objectives. To evaluate new mouth rinse containing sea salt, xylitol, and lysozyme on biofilm formation and gingival health in a group of young adults. Methods. The subjects were divided into two groups of 15 subjects each: control (A and experimental group (B. The Turesky modification of Quigley-Hein plaque index was used to evaluate plaque scores while the presence or absence of gingival bleeding was used to determine gingival health. Measurements were done at baseline and at the end of the one-month trial period by one blinded examiner on six representative teeth. Group (A maintained standardized oral health practices for the duration of the experiment. In addition, group (B rinsed with a tablespoon of the provided sea salt mouth rinse for 30 seconds once in the morning and at night. After the 30-day trial period, subjects in both groups were reassessed as per baseline. Results. There were no statistically significant differences in the overall reduction from baseline in the mean plaque and gingivitis scores on all surfaces or on individual surfaces. Conclusion. Within the limitations of the study, rinsing with sea salt for thirty days did not affect the gingival and plaque scores in a group of young adults.

Demonstration of immunogenic keratan sulphate in commercial chondroitin 6-sulphate from shark cartilage. Implications for ELISA assays

DEFF Research Database (Denmark)

Møller, H J; Møller-Pedersen, T; Damsgaard, T E

1995-01-01

The prototype monoclonal keratan sulphate (KS) antibody 5D4 that is widely used for detection of KS in tissues and biological fluids reacts strongly with commercial low grade shark cartilage chondroitin 6-sulphate. Characterization of the immunogenic material by chondroitinase ABC digestion, ELISA...... cartilage chondroitin 6-sulphate is an easy accessible source of immunogenic KS that can be used as a reference standard and as coating antigen in KS-ELISAs. The concentration of immunogenic KS in synovial fluid measured with an ELISA based solely on reagents of shark cartilage chondroitin 6-sulphate...... correlated well (r = 0.90) with the concentrations obtained with a traditional KS-ELISA that uses purified aggrecan as standard and coating antigen, and KS in both serum and synovial fluid could be measured with sufficient linearity....

The effects of soluble salts at the metal/paint interface: advances in knowledge

OpenAIRE

Fuente, Daniel de la; Chico, Belén; Morcillo, Manuel

2006-01-01

The presence of soluble salts (particularly sulphates and chlorides) at the metal/paint interface is known to have a detrimental effect on the integrity of most paint systems. Though this is a long-standing problem, it has recently come to receive greater attention from the protective coatings industry. International Standards Organization (ISO) has for some time been trying to develop a standard about guidance levels for water-soluble salt contamination before the application of paints and r...

Effectivness of dexametasone vs. Magnesium sulphate in postoperative analgesia: Dexametasone vs. Magnesium sulphate

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Dautaj Brikena

2016-01-01

Full Text Available Introduction: Preoperative use of additive substances may be very helpful in perioperative acute pain management. Intravenous administration of dexametasone in preoperative period prevents postoperative nausea and vomiting but also provides better pain relief. It is also well known that magnesium sulphate (the NMDA receptor's antagonist by its central mechanism of action may be effective in postoperative pain control. Aim: The purpose of this study was to evaluate the effect of dexametasone and magnesium sulphate on postoperative pain management in patients undergoing abdominal surgery (open cholecystectomy. Methods: Seventy eight patients scheduled for elective surgery (open cholecystectomy were included in this study. This was the prospective cohort randomized placebo- controlled study. A total of 78 patients were randomized into three groups. Each group had twenty six patients. The group D, received dexametasone 0.1 mg/ kg iv 30 minutes before surgery. The group M received magnesium sulphate 3 mg/kg iv 30 minutes before surgery. The third group S was placebo group and patients in this group received saline in the same volume for each patient. For pain control after surgery all patients received tramadol 0.9-1.2 mg/kg and diklophenac 1.76 mg/kg. When necessary (VAS ≥ 7, morphine sulphate in dose 0.15 mg/kg was administred subcutaneously For treatment of emetic episodes metoclopramid 10 mg iv. was used. The patients were observed for intensity of pain measured VAS 0-10, pain relief and satisfaction with therapy, sedation, adverse events, emetic episodes and hemodynamic parameters. Results: There was no difference between groups regarding demographic data (age, gender, body weight, ASA score, comorbidity, duration of surgery and anesthesia and amount of fentanyl received during surgery. In group D 11.54% of patients received additional analgesia (morphine sulphate 0.15 mg/kg sc in the first 4 hours and 27% of patients in the first 24 hours

Modelling the chemically aged and mixed aerosols over the eastern central Atlantic Ocean – potential impacts

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M. Astitha

2010-07-01

Full Text Available Detailed information on the chemical and physical properties of aerosols is important for assessing their role in air quality and climate. This work explores the origin and fate of continental aerosols transported over the Central Atlantic Ocean, in terms of chemical composition, number and size distribution, using chemistry-transport models, satellite data and in situ measurements. We focus on August 2005, a period with intense hurricane and tropical storm activity over the Atlantic Ocean. A mixture of anthropogenic (sulphates, nitrates, natural (desert dust, sea salt and chemically aged (sulphate and nitrate on dust aerosols is found entering the hurricane genesis region, most likely interacting with clouds in the area. Results from our modelling study suggest rather small amounts of accumulation mode desert dust, sea salt and chemically aged dust aerosols in this Atlantic Ocean region. Aerosols of smaller size (Aitken mode are more abundant in the area and in some occasions sulphates of anthropogenic origin and desert dust are of the same magnitude in terms of number concentrations. Typical aerosol number concentrations are derived for the vertical layers near shallow cloud formation regimes, indicating that the aerosol number concentration can reach several thousand particles per cubic centimetre. The vertical distribution of the aerosols shows that the desert dust particles are often transported near the top of the marine cloud layer as they enter into the region where deep convection is initiated. The anthropogenic sulphate aerosol can be transported within a thick layer and enter the cloud deck through multiple ways (from the top, the base of the cloud, and by entrainment. The sodium (sea salt related aerosol is mostly found below the cloud base. The results of this work may provide insights relevant for studies that consider aerosol influences on cloud processes and storm development in the Central Atlantic region.

Effects of Manganese (Ii Sulphate on Structural, Spectral, Optical, Thermal and Mechanical Properties of L-Alanine Sodium Sulphate Single Crystals

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F. Praveena

2017-04-01

Full Text Available New Non-linear Optical materials have been attracting in the research world for their potential applications in emerging opto-electronic technology. The dipolar nature of amino acid leads to peculiar physical and chemical properties, thus making a good candidate for NLO applications. Single crystals of manganese(II sulphate doped L-Alanine sodium sulphate(LASS has been synthesized by slow evaporation technique. Structural property of the grown crystals are characterized by X-ray powder diffraction,FT-IR spectral analysis conforms all the functional groups. Thermogravity (TG and differential themogravimetric (DTA analysis have been performed to study the thermal stability of the crystals. The second harmonic generation efficiency was measured by Kurtz-Perry powder technique. The transmission and absorption of electromagnetic radiation is analysed through UV-VIS spectrum. Microhardness was measured at different applied load to understand the mechanical stability of the crystal.

Building materials as intrinsic sources of sulphate: A hidden face of salt weathering of historical monuments investigated through multi-isotope tracing (B, O, S)

International Nuclear Information System (INIS)

Kloppmann, W.; Bromblet, P.; Vallet, J.M.; Verges-Belmin, V.; Rolland, O.; Guerrot, C.; Gosselin, C.

2011-01-01

Sulphate neoformation is a major factor of degradation of stone monuments. Boron, sulphur and oxygen isotope signatures were investigated for five French historical monuments (Bourges, Chartres and Marseille cathedrals, Chenonceau castle, and Versailles garden statues) to investigate the role of intrinsic sulphate sources (gypsum plasters and mortars) in stone degradation, compared to the influence of extrinsic sources such as atmospheric pollution. Gypsum plasters and gypsum-containing mortars fall systematically in the δ 34 S and δ 18 O range of Paris Basin Eocene evaporites indicating the origin of the raw materials (so-called 'Paris plaster'). Black crusts show the typical S and O isotope signatures observed elsewhere in Europe that can be attributed to atmospheric pollution, together with a marine component for Marseille. Boron isotopes for black crusts indicate coal combustion as principal boron source. Mortar isotope compositions discriminate three types, one similar to gypsum plasters, one strongly depleted in 34 S, attributed to pyrite oxidation, and a third one close to atmospheric sulphates. The isotopic composition of sulphates and boron of most degraded building stones of the different monuments is well explained by the identified sulphate sources. In several cases (in particular for Chenonceau and Bourges, to some extent for Chartres), the impact of gypsum plaster as building and restoration material on the degradation of the stones in its vicinity was clearly demonstrated. The study illustrates the usefulness of multi-isotope studies to investigate stone degradation factors, as the combination of several isotope systematics increases the discriminatory power of isotope studies with respect to contaminant sources. - Research Highlights: → Insight in stone weathering mechanisms by multi-isotope fingerprinting (B, S, O). → Intrinsic sulphate sources (gypsum plaster, mortar) contribute to stone degradation. → Origin of building materials

Building materials as intrinsic sources of sulphate: A hidden face of salt weathering of historical monuments investigated through multi-isotope tracing (B, O, S)

Energy Technology Data Exchange (ETDEWEB)

Kloppmann, W., E-mail: w.kloppmann@brgm.fr [BRGM, BP 6009, F-45060 Orleans cedex 2 (France); Bromblet, P.; Vallet, J.M. [CICRP, 21, rue Guibal, F-13003 Marseille (France); Verges-Belmin, V. [LRMH, 29, rue de Paris, F-77420 Champs sur Marne (France); Rolland, O. [Independent restorer, 3, rue du Gue, 37270 Montlouis s/Loire (France); Guerrot, C. [BRGM, BP 6009, F-45060 Orleans cedex 2 (France); Gosselin, C. [BRGM, BP 6009, F-45060 Orleans cedex 2 (France); LRMH, 29, rue de Paris, F-77420 Champs sur Marne (France)

2011-04-01

Sulphate neoformation is a major factor of degradation of stone monuments. Boron, sulphur and oxygen isotope signatures were investigated for five French historical monuments (Bourges, Chartres and Marseille cathedrals, Chenonceau castle, and Versailles garden statues) to investigate the role of intrinsic sulphate sources (gypsum plasters and mortars) in stone degradation, compared to the influence of extrinsic sources such as atmospheric pollution. Gypsum plasters and gypsum-containing mortars fall systematically in the {delta}{sup 34}S and {delta}{sup 18}O range of Paris Basin Eocene evaporites indicating the origin of the raw materials (so-called 'Paris plaster'). Black crusts show the typical S and O isotope signatures observed elsewhere in Europe that can be attributed to atmospheric pollution, together with a marine component for Marseille. Boron isotopes for black crusts indicate coal combustion as principal boron source. Mortar isotope compositions discriminate three types, one similar to gypsum plasters, one strongly depleted in {sup 34}S, attributed to pyrite oxidation, and a third one close to atmospheric sulphates. The isotopic composition of sulphates and boron of most degraded building stones of the different monuments is well explained by the identified sulphate sources. In several cases (in particular for Chenonceau and Bourges, to some extent for Chartres), the impact of gypsum plaster as building and restoration material on the degradation of the stones in its vicinity was clearly demonstrated. The study illustrates the usefulness of multi-isotope studies to investigate stone degradation factors, as the combination of several isotope systematics increases the discriminatory power of isotope studies with respect to contaminant sources. - Research Highlights: {yields} Insight in stone weathering mechanisms by multi-isotope fingerprinting (B, S, O). {yields} Intrinsic sulphate sources (gypsum plaster, mortar) contribute to stone degradation

Worth its salt?

Science.gov (United States)

The idea that all underground salt deposits can serve as storage sites for toxic and nuclear waste does not always hold water—literally. According to Daniel Ronen and Brian Berkowitz of Israel's Weizmann Institute of Science and Yoseph Yechieli of the Geological Survey of Israel, some buried salt layers are in fact highly conductive of liquids, suggesting that wastes buried in their confines could easily leech into groundwater and nearby soil.When drilling three wells into a 10,000-year-old salt layer near the Dead Sea, the researchers found that groundwater had seeped into the layer and had absorbed some of its salt.

Basement inheritance and salt tectonics in the SE Barents Sea: Insights from new potential field data

Science.gov (United States)

Gernigon, L.; Broenner, M.; Dumais, M. A.; Gradmann, S.; Grønlie, A.; Nasuti, A.; Roberts, D.

2017-12-01

The tectonic evolution of the former `grey zone' between Russia and Norway has so far remained poorly constrained due to a lack of geophysical data. In 2014, we carried out a new aeromagnetic survey (BASAR-14) in the southern part of the new Norwegian offshore territory. Caledonian and Timanian structures, highlighted by the new potential field data, dominate the basement patterns and have exerted a strong influence on the structure and development of the overlying basins and basement highs. Clearly associated with NW-SE-oriented Timanian trends, the Tiddlybanken Basin represents an atypical sag basin that developed at the southern edge of the Fedynsky High. Regional extension and rapid sedimentation initiated the salt tectonics in the Barents Sea in the Early Triassic. Some of the pillows became diapiric during the Early Triassic and rejuvenated during subsequent Jurassic-Tertiary episodes of regional extension and/or compression. At present, quite a few large diapiric salt domes along the Nordkapp and Tiddlybanken basins are relatively shallow, locally reaching the seabed and thus show a clear bathymetric and magnetic signature. Quantitative modelling along 2D seismic transects was also carried out to constrain the structural and basement composition of the study area. The predominant NE-SW Mesozoic trend of the Nordkapp Basin represents a major crustal hinge zone between the Finnmark Platform, poorly affected by major crustal deformation, and the Bjarmeland Platform where Late Palaeozoic rifting controlled the widespread accumulation of salt deposits in Late Carboniferous-Early Permian time. The entire structure and segmentation of the Nordkapp Basin have been influenced by the inherited basement configuration highlighted by the new aeromagnetic data. Both the Nordkapp and the Tiddlybanken basins appear to lie at the edge of a peculiar thick and rigid crustal feature that coincides with a highly magnetic region. The abrupt termination of the eastern Nordkapp

Demonstration of immunogenic keratan sulphate in commercial chondroitin 6-sulphate from shark cartilage. Implications for ELISA assays

DEFF Research Database (Denmark)

Møller, H J; Møller-Pedersen, T; Damsgaard, T E

1995-01-01

The prototype monoclonal keratan sulphate (KS) antibody 5D4 that is widely used for detection of KS in tissues and biological fluids reacts strongly with commercial low grade shark cartilage chondroitin 6-sulphate. Characterization of the immunogenic material by chondroitinase ABC digestion, ELISA...... inhibition studies, immunoblotting and HPLC analyses confirmed the presence of substantial amounts of KS, probably as a large proteoglycan (> 120 kDa). Commercial and heterogenic glycosaminoglycan preparations therefore must be used with great caution in immunological analyses. On the other hand the shark...... cartilage chondroitin 6-sulphate is an easy accessible source of immunogenic KS that can be used as a reference standard and as coating antigen in KS-ELISAs. The concentration of immunogenic KS in synovial fluid measured with an ELISA based solely on reagents of shark cartilage chondroitin 6-sulphate...

Extraction of sulphates by long chain amines

International Nuclear Information System (INIS)

Boirie, Ch.

1959-05-01

The extraction of sulphuric acid by long chain amines in organic solution has been studied with a view to determining the value of the stability constants of the amine sulphates and bi-sulphates formed. We have concentrated chiefly on uranium sulphate and thorium sulphate. The formulae of the complexes extractable with amines have been established, as well as the corresponding dissociation constants. We have observed that for uranium sulphate the formula of the complex depends only on the nature of the amine, whereas for thorium this formula varies with the amine structure. From the formulae determined and the value of the constants calculated, we have been able to establish the best conditions for uranium and thorium extraction and also for a separation of these two elements. Finally we propose an application of this study to the determination of uranium in ores, where the separation of uranium by this method is particularly easy and complete. (author) [fr

Character of meteoric leaks in the salt mines of south Louisiana, U.S.A.

Science.gov (United States)

Kumar, Madhurendu B.

1983-10-01

The brine leaks of salt mines of south Louisiana are of two genetic categories: meteoric and non-meteoric (connate/formation water type), as established essentially on the basis of oxygen- and hydrogen-isotope analyses. This paper highlights the hydrochemical aspects of those mine leaks and develops simple non-isotopic criteria to differentiate the meteoric leaks from the non-meteoric. The meteoric leaks of the salt mines generally occur down to a depth level of 214 m (700 ft.) (below mean sea level) below which the leaks are mostly non-meteoric. The meteoric brine is essentially Na1bCl in type, reflecting the mineralogy of almost pure halite (with ˜ 1-2% anhydrite) of the Gulf (of Mexico) Coast dome salt. The meteoric leaks are distinctly different from the non-meteoric leaks on the log-log plots of chloride concentrations vs. those of Ca 2+, Mg 2+, K +, Sr + and Br -, in all of which the meteoric brines are conspicuously low. This study is potentially useful in the development of a mine or crypt in salt dome(s) under consideration for possible nuclear-waste isolation in the Gulf Coast region.

Simple simultaneous determination of soluble and insoluble trace metal components in sea salts by a combined coprecipitation/X-ray fluorescence method

International Nuclear Information System (INIS)

Iwatsuki, Masaaki; Ali, Muhammad; Kyotani, Tomohiro; Fukasawa, Tsutomu

1996-01-01

An X-ray fluorescence method using the coprecipitation-preconcentration technique has been developed for simple determination of both acid-soluble and insoluble trace metal components, such as manganese, iron, nickel, copper and zinc in sea salts. A salt sample is dissolved in a nitric acid solution, and the residue is filtered off onto a membrane filter. After the pH is adjusted to 7-8, the filtrate is boiled, followed by addition of aluminum carrier, oxine and thionalide solutions. The solution is re-adjusted to pH 9, and kept at 80-85degC for 60 min. The precipitates are filtered off onto another membrane filter. X-Ray fluorescence intensities from two filters loaded with the residue and precipitates are measured and the concentrations of the elements are determined simultaneously using the calibration curves. Detection limits were 0.01 μg g -1 for manganese and copper, 0.04 μg g -1 for nickel and zinc, and 0.05 μg g -1 for iron, regardless of the soluble and the insoluble components. The present method was successfully applied to the analysis of sea salt samples. (author)

Nutrient enrichment and precipitation changes do not enhance resiliency of salt marshes to sea level rise in the Northeastern U.S.

Science.gov (United States)

In the U.S. Northeast, salt marshes are exceptionally vulnerable to the effects of accelerated sea level rise as compensatory mechanisms relying on positive feedbacks between inundation and sediment deposition are insufficient to counter inundation increases in low turbidity tida...

Sulphate deposition by precipitation into Lake Ontario

Energy Technology Data Exchange (ETDEWEB)

Shaw, R W; Whelpdale, D M

1973-01-01

Measurements of sulphate concentration in precipitation from individual snow storms of several hours duration in the western Lake Ontario region indicate that approximately 9-66 mg/M/sub 2/ of SO/sub 4//sup 2 -/ is being deposited into the lake per storm. This amount is up to several times more than daily average values over long periods found by other workers. Using a mean sulphate concentration of 4 mg/l and an annual accumulation of precipitation of 760 mm, the yearly sulphate deposition by precipitation is about 0.1% of the total mass of sulphate in the lake; however, more significantly, it is of the same order of magnitude as that discharged directly into the lake by industry.

Study of the structure of H₂SO₄-amine Primene 81R and Fe(III-amine Primene 81R sulphate compounds by infrared spectroscopy

Directory of Open Access Journals (Sweden)

Alguacil, F. J.

1999-08-01

Full Text Available The primary amine Primene 81R extracts sulphuric acid from aqueous solutions to form the corresponding sulphate and bisulphate salts. The infrared study shows that in the sulphate salt, the sulphate group presents a T_d symmetry, whereas the amine bisulphate presents a C_3v symmetry for the bisulphate group. The former of the above compounds, the amine sulphate, is complexed to Fe(III in sulphate media, and two complexes are extracted depending on temperature. At 8°C or lower temperatures a complex with the stoichiometric formula 4(RNH₃₂SO₄ (Fe(OHSO₄2 is formed, whereas at 50°C or higher temperatures the complex with the stoichiometric formula 3(RNH₃₂SO₄ (Fe(OHSO₄₂ is formed. The infrared spectrum of both complexes is very similar and it is consistent with a weaker interaction between the protons associated with the amine group and the anion, and with a change in the symmetry of the sulphate group respect to the symmetry presented in the amine sulphate salt.

La amina primaria Primene 81R extrae al ácido sulfúrico de los medios acuosos para formar las sales sulfato y bisulfato. El estudio IR muestra que en la sal sulfato, el grupo sulfato presenta una simetría T_d, mientras que en la sal bisulfato este grupo presenta una simetría C_3v. La sal sulfato compleja al Fe(III, formando dos compuestos en función de la temperatura de reacción. A temperaturas iguales a 8°C o inferiores se forma el compuesto de estequiometría 4(RNH₃₂SO₄ (Fe(OHSO₄₂, mientras que a temperaturas iguales o superiores a 50°C la estequiometría del compuesto extraído es 3(RNH₃₂SO₄ (Fe(OHSO₄₂. El espectro infrarrojo de ambos compuestos es muy parecido y es consistente, tanto con una interacción d

Mortar and concrete based on calcium sulphate binders

NARCIS (Netherlands)

Bakker, J.J.F.; Brouwers, H.J.H.; Fischer, H.B

2006-01-01

In this study both hemi-hydrate and anhydrite are tested as calcium sulphate binders for structural mortar and concrete. The advantage of using calcium sulphates instead of cement as a binder is the fact that the production of calcium sulphate is more environmental friendly than that of cement. For

A Subject of Sea and Salty Sediment: Diasporic Labor and Queer (Belonging in Monique Truong’s The Book of Salt

Directory of Open Access Journals (Sweden)

Michelle Peek

2012-06-01

Full Text Available Caught having an affair while employed at the home of the governor-general of Saigon, Vietnamese cook, migrant worker, and narrator of Monique Truong’s The Book of Salt, Binh, is cast out of his natal home, and sets off for the open sea, winding up as a live-in cook in the household of lesbian couple Gertrude Stein and Alice B. Toklas. As an abstract source of labor and culinary pleasure to those he encounters in Paris, Binh concludes, despondently, that he is, “nothing but a series of destinations with no meaningful expanses in between.” Yet the “expanses in between,” most notably in reference to waterways, allude to a central trope of Vietnamese culture. Incorporating Vietnamese symbolism with formative migratory experiences, this essay argues that Truong constructs a subject who can be read through both affective forms of national belonging as well as a broader queer diasporic community. It also explores Binh’s percipient tongue as one that is ever critical of the dynamics of power and privilege, and ever sensitive to the variances in salt (of sea, sweat, tears. The Book of Salt thus mediates the possibility of a gustatory epistemology and community constituted in the sensate, attuned to divergent experiences of mobility, labor, and love.

Physicochemical and in vitro deposition properties of salbutamol sulphate/ipratropium bromide and salbutamol sulphate/excipient spray dried mixtures for use in dry powder inhalers.

Science.gov (United States)

Corrigan, Deirdre O; Corrigan, Owen I; Healy, Anne Marie

2006-09-28

The physicochemical and aerodynamic properties of spray dried powders of the drug/drug mixture salbutamol sulphate/ipratropium bromide were investigated. The in vitro deposition properties of spray dried salbutamol sulphate and the spray dried drug/excipient mixtures salbutamol sulphate/lactose and salbutamol sulphate/PEG were also determined. Spray drying ipratropium bromide monohydrate resulted in a crystalline material from both aqueous and ethanolic solution. The product spray dried from aqueous solution consisted mainly of ipratropium bromide anhydrous. There was evidence of the presence of another polymorphic form of ipratropium bromide. When spray dried from ethanolic solution the physicochemical characterisation suggested the presence of an ipratropium bromide solvate with some anhydrous ipratropium bromide. Co-spray drying salbutamol sulphate with ipratropium bromide resulted in amorphous composites, regardless of solvent used. Particles were spherical and of a size suitable for inhalation. Twin impinger studies showed an increase in the fine particle fraction (FPF) of spray dried salbutamol sulphate compared to micronised salbutamol sulphate. Co-spray dried salbutamol sulphate:ipratropium bromide 10:1 and 5:1 systems also showed an increase in FPF compared to micronised salbutamol sulphate. Most co-spray dried salbutamol sulphate/excipient systems investigated demonstrated FPFs greater than that of micronised drug alone. The exceptions to this were systems containing PEG 4000 20% or PEG 20,000 40% both of which had FPFs not significantly different from micronised salbutamol sulphate. These two systems were crystalline unlike most of the other spray dried composites examined which were amorphous in nature.

Synthesis, characterization and antimicrobial activity of dextran sulphate stabilized silver nanoparticles

Science.gov (United States)

Cakić, Milorad; Glišić, Slobodan; Nikolić, Goran; Nikolić, Goran M.; Cakić, Katarina; Cvetinov, Miroslav

2016-04-01

Dextran sulphate stabilized silver nanoparticles (AgNPs - DS) were synthesized from aqueous solution of silver nitrate (AgNO3) and dextran sulphate sodium salt (DS). The characterization of AgNPs - DS was performed by ultraviolet-visible spectroscopy (UV-VIS), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and antimicrobial activity. The formation of AgNPs - DS was monitored by colour changes of the reaction mixture from yellowish to brown and by measuring the surface plasmon resonance absorption peak in UV-VIS spectra at 420 nm. The SEM analysis was used for size and shape determination of AgNPs - DS. The presence of elemental silver and its crystalline structure in AgNPs - DS were confirmed by EDX and XRD analyses. The possible functional groups of DS responsible for the reduction and stabilization of AgNPs were determinated by FTIR spectroscopy. The AgNPs - DS showed strong antibacterial activity against Staphylococcus aureus ATCC 25923, Bacillus cereus ATCC 11778, Bacillus luteus in haus strain, Bacillus subtilis ATTC 6633, Listeria monocytogenes ATCC 15313, Escherichia coli ATTC 25922, Pseudomonas aeruginosa ATTC 27853, Klebsiella pneumoniae ATTC 700603, Proteus vulgaris ATTC 8427, and antifungal activity against Candida albicans ATTC 2091.

Magnesium sulphate and other anticonvulsants for women with pre-eclampsia.

Science.gov (United States)

Duley, Lelia; Gülmezoglu, A Metin; Henderson-Smart, David J; Chou, Doris

2010-11-10

Eclampsia, the occurrence of a seizure (fit) in association with pre-eclampsia, is rare but potentially life-threatening. Magnesium sulphate is the drug of choice for treating eclampsia. This review assesses its use for preventing eclampsia. To assess the effects of magnesium sulphate, and other anticonvulsants, for prevention of eclampsia. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (4 June 2010), and the Cochrane Central Register of Controlled Trials Register (The Cochrane Library 2010, Issue 3). Randomised trials comparing anticonvulsants with placebo or no anticonvulsant, or comparisons of different drugs, for pre-eclampsia. Two authors assessed trial quality and extracted data independently. We included 15 trials. Six (11,444 women) compared magnesium sulphate with placebo or no anticonvulsant: magnesium sulphate more than a halved the risk of eclampsia (risk ratio (RR) 0.41, 95% confidence interval (CI) 0.29 to 0.58; number needed to treat for an additional beneficial outcome (NNTB) 100, 95% CI 50 to 100), with a non-significant reduction in maternal death (RR 0.54, 95% CI 0.26 to 1.10) but no clear difference in serious maternal morbidity (RR 1.08, 95% CI 0.89 to 1.32). It reduced the risk of placental abruption (RR 0.64, 95% CI 0.50 to 0.83; NNTB 100, 95% CI 50 to 1000), and increased caesarean section (RR 1.05, 95% CI 1.01 to 1.10). There was no clear difference in stillbirth or neonatal death (RR 1.04, 95% CI 0.93 to 1.15). Side effects, primarily flushing, were more common with magnesium sulphate (24% versus 5%; RR 5.26, 95% CI 4.59 to 6.03; number need to treat for an additional harmful outcome (NNTH) 6, 95% CI 5 to 6).Follow-up was reported by one trial comparing magnesium sulphate with placebo: for 3375 women there was no clear difference in death (RR 1.79, 95% CI 0.71 to 4.53) or morbidity potentially related to pre-eclampsia (RR 0.84, 95% CI 0.55 to 1.26) (median follow-up 26 months); for 3283 children exposed in utero

Sulphate reduction and vertical distribution of sulphate-reducing bacteria quantified by rRNA slot-blot hybridization in a coastal marine sediment

DEFF Research Database (Denmark)

Sahm, K.; MacGregor, BJ; Jørgensen, BB

1999-01-01

In the past, enumeration of sulphate-reducing bacteria (SRB) by cultivation-based methods generally contradicted measurements of sulphate reduction, suggesting unrealistically high respiration rates per cell. Here, we report evidence that quantification of SRB rRNA by slot-blot hybridization......, directly above the sulphate reduction maximum. Cell numbers calculated by converting the relative contribution of SRB rRNA to the percentage of DAPI-stained cells indicated a population size for SRB of 2.4-6.1 x 10(8) cells cm(-3) wet sediment. Cellular sulphate reduction rates calculated on the basis...

Submarine Salt Karst Terrains

Directory of Open Access Journals (Sweden)

Nico Augustin

2016-06-01

Full Text Available Karst terrains that develop in bodies of rock salt (taken as mainly of halite, NaCl are special not only for developing in one of the most soluble of all rocks, but also for developing in one of the weakest rocks. Salt is so weak that many surface-piercing salt diapirs extrude slow fountains of salt that that gravity spread downslope over deserts on land and over sea floors. Salt fountains in the deserts of Iran are usually so dry that they flow at only a few cm/yr but the few rain storms a decade so soak and weaken them that they surge at dm/day for a few days. We illustrate the only case where the rates at which different parts of one of the many tens of subaerial salt karst terrains in Iran flows downslope constrains the rates at which its subaerial salt karst terrains form. Normal seawater is only 10% saturated in NaCl. It should therefore be sufficiently aggressive to erode karst terrains into exposures of salt on the thousands of known submarine salt extrusions that have flowed or are still flowing over the floors of hundreds of submarine basins worldwide. However, we know of no attempt to constrain the processes that form submarine salt karst terrains on any of these of submarine salt extrusions. As on land, many potential submarine karst terrains are cloaked by clastic and pelagic sediments that are often hundreds of m thick. Nevertheless, detailed geophysical and bathymetric surveys have already mapped likely submarine salt karst terrains in at least the Gulf of Mexico, and the Red Sea. New images of these two areas are offered as clear evidence of submarine salt dissolution due to sinking or rising aggressive fluids. We suggest that repeated 3D surveys of distinctive features (± fixed seismic reflectors of such terrains could measure any downslope salt flow and thus offer an exceptional opportunity to constrain the rates at which submarine salt karst terrains develop. Such rates are of interest to all salt tectonicians and the many

Biosedimentary and geochemical constraints on the precipitation of mineral crusts in shallow sulphate lakes

Science.gov (United States)

Cabestrero, Óscar; del Buey, Pablo; Sanz-Montero, M. Esther

2018-04-01

Seasonal desiccation of Mg2+-(Na+)-(Ca2+)-SO42--(Cl-) saline lakes in La Mancha (Central Spain) that host microbial mats led to the precipitation of hydrated Na-Mg sulphates and gypsum. Sulphates precipitated in the submerged conditions form extensive biolaminites, whilst in marginal areas they produce thin crusts. Sedimentological, mineralogical, petrographic and high resolution textural studies reveal that the crusts were formed within the benthic microbial mats that thrive at salinities ranging from 160 to 340 g·L-1. The minerals of the crusts are primary bloedite (Na2Mg(SO4)2·4H2O), epsomite (MgSO4·7H2O), gypsum (CaSO4·2H2O) and mirabilite (Na2SO4·10H2O), as well as secondary hexahydrite (MgSO4·6H2O) and thenardite (Na2SO4). Primary bloedite crystals, which form the framework of surficial and submerged crusts are seen to nucleate subaqueously and grow incorporatively within the matgrounds. Displacive and incorporative epsomite grows on previous bloedite crystals and also on the ground. Mirabilite is precipitated rapidly at the brine-air interface over bloedite and epsomite. Hexahydrite and thenardite are formed due to dehydration of epsomite and mirabilite, respectively. Hydrochemical modeling with PHREEQC indicated that evaporitic biolaminites are forming from brines undersaturated with respect to bloedite, epsomite and mirabilite, which suggests that the microorganisms contribute to the heterogeneous nucleation of the sulphates in the microbial mats. Unlike carbonates, the influence of microbes on the growth and morphology of complicated double salts such as bloedite has not been documented previously and provides a new perspective on the formation of hydrated sulphate minerals that are common on Earth as well as other planets.

Aldosterone hypersecretion in “non-salt-losing” congenital adrenal hyperplasia

Science.gov (United States)

Bartter, Frederic C.; Henkin, Robert I.; Bryan, George T.

1968-01-01

Patients with the “non-salt-losing” form of the adrenogenital syndrome were studied before and after suppression of adrenal cortical activity with carbohydrate-active steroids. The response of aldosterone secretion to sodium deprivation was measured; in some patients response to adrenocorticotropic hormone (ACTH) was measured as well. The aldosterone secretion was normal and responded normally to sodium deprivation in all patients studied during suppression with carbohydrate-active steroids. This finding suggests that 21-hydroxylation of progesterone is normal in this syndrome. The sole abnormality in the production of aldosterone in these patients was found to be excessive secretion of aldosterone while they were not receiving suppressive doses of carbohydrate-active steroids. This finding strongly supports the view that the biogenetic pathways through which aldosterone is produced from progesterone are intact in this syndrome. No patient showed hypertension or hypokalemic alkalosis despite very high aldosterone secretion rates. This observation suggests that the hyper-aldosteronism is secondary to a tendency to sodium loss in the patient whose ACTH production is not suppressed. These studies provide additional evidence in support of the hypothesis that the salt-losing and “non-salt-losing” forms of adrenogenital syndrome are genetically and biochemically distinct. PMID:4299011

Detection of human influence on sea-level pressure.

Science.gov (United States)

Gillett, Nathan P; Zwiers, Francis W; Weaver, Andrew J; Stott, Peter A

2003-03-20

Greenhouse gases and tropospheric sulphate aerosols--the main human influences on climate--have been shown to have had a detectable effect on surface air temperature, the temperature of the free troposphere and stratosphere and ocean temperature. Nevertheless, the question remains as to whether human influence is detectable in any variable other than temperature. Here we detect an influence of anthropogenic greenhouse gases and sulphate aerosols in observations of winter sea-level pressure (December to February), using combined simulations from four climate models. We find increases in sea-level pressure over the subtropical North Atlantic Ocean, southern Europe and North Africa, and decreases in the polar regions and the North Pacific Ocean, in response to human influence. Our analysis also indicates that the climate models substantially underestimate the magnitude of the sea-level pressure response. This discrepancy suggests that the upward trend in the North Atlantic Oscillation index (corresponding to strengthened westerlies in the North Atlantic region), as simulated in a number of global warming scenarios, may be too small, leading to an underestimation of the impacts of anthropogenic climate change on European climate.

Fractal-like thickness and topography of the salt layer in a pillows province of the southern North Sea

Science.gov (United States)

Hernandez Maya, K.; Mitchell, N. C.; Huuse, M.

2017-12-01

Salt topography and thickness variations are important for testing theories of how halokinetic deformation proceeds. The ability to predict thickness variations of salt at small scale is also important for reservoir evaluations, as breach of the salt layer can lead to loss of petroleum fluids and can be difficult to evaluate from seismic reflection data. Relevant to these issues, we here report analysis of data on salt layer topography and thickness from the southern North Sea, where the salt is organized into pillows. These data were derived by the Geological Survey of the Netherlands (TNO) from industry 3D seismic reflection data combined with a dense network of well information. Highs and lows in the topography of the upper salt interface occur spaced over a variety of lengthscales. Power spectral analysis of the interface topography reveals a simple inverse power law relationship between power spectral density and spatial wave number. The relationship suggests that the interface is a self-affine fractal with a fractal dimension of 2.85. A similar analysis of the salt layer thickness also suggests a fractal-like power law. Whereas the layer thickness power law is unsurprising as the underlying basement topography dominates the thickness and it also has a fractal-like power spectrum, the salt topography is not so easily explained as not all the basement faults are overlaid by salt pillows, instead some areas of the dataset salt thinning overlies faults. We consider instead whether a spatially varied loading of the salt layer may have caused this fractal-like geometry. Varied density and thickness of overburdening layers seem unlikely causes, as thicknesses of layers and their reflectivities do not vary sympathetically with the topography of the interface. The composition of the salt layer varies with the relative proportions of halite and denser anhydrite and other minerals. Although limited in scope and representing the mobilized salt layer, the information from

Ferrous sulphate mono and heptahydrate reduction of hexavalent chromium in cement: effectiveness and storability

Directory of Open Access Journals (Sweden)

Valverde, J. L.

2005-09-01

Full Text Available In Community legislation, substances containing hexavalent chromium are classified as carcinogenic, mutagenic and sensitizing. In cement, hexavalent chromium intensifies sensitization and may set off severe allergic reactions in workers in routine contact with the product, whether in the factory or on construction sites. The allergic or contact dermatitis causes is a very painful disease that may lead to permanent worker disability. According to Directive 2003/53/EC of the European Parliament and the Council, Governments of all member countries will be required to prohibit the marketing and use, as of 17 January 2005, of any cement or cement preparation containing more than 2 ppm of chromium (VI. Hexavalent chromium can be reduced with ferrous sulphate to trivalent chromium, which is water-insoluble and therefore innocuous to the skin. The present paper reports the effects of adding ferrous sulphate mono- or heptahydrate to a commercial cement and the storage time of the mix on the concentration of hexavalent chromium. The salts studied were found to effectively reduce hexavalent chromium in cement for at least three months.

Las sustancias que contienen cromo hexavalente están clasificadas en la legislación comunitaria como sustancias carcinogénicas, mutagénicas y sensibilizantes. El cromo hexavalente del cemento potencia la sensibilización y provoca graves reacciones alérgicas que sufren bastante a menudo los trabajadores que lo manipulan habitualmente, ya sea en fábrica o en el sector de la construcción. La dermatitis alérgica o de contacto que produce es muy dolorosa y puede dejar a los trabajadores en estado de discapacidad. La Directiva 2003/53/CE del Parlamento Europeo y del Consejo, exige a los Gobiernos de los países miembros, que a partir del 17 de enero de 2005, prohiban el uso y la comercialización de todos aquellos cementos y preparados que contengan cemento, cuyo contenido en cromo (VI soluble, una vez hidratados

Alaska Steller sea lion Count Database (Non-pups)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This database contains counts of adult and juvenile (non-pup) Steller sea lions on rookeries and haulouts in Alaska made between 1904 and 2015. Non-pup counts have...

Influence of different salting processes on the evolution of the volatile metabolites of vacuum-packed fillets of farmed and wild sea bass (Dicentrarchus labrax) stored under refrigeration conditions: a study by SPME-GC/MS.

Science.gov (United States)

Vidal, Natalia P; Manzanos, María J; Goicoechea, Encarnación; Guillén, María D

2017-02-01

Fish shelf-life extension is a topic of great interest. In this study the behaviour of salted and unsalted farmed and wild European sea bass (Dicentrarchus labrax) fillets during storage was analysed through the evolution of their volatile metabolites. Farmed and wild sea bass fillets were brine-salted for 15 or 75 min, or dry-salted, vacuum-packed and stored at 4 °C for up to 1 month, and their headspaces were studied by Solid Phase Micro extraction-Gas Chromatography/Mass Spectrometry (SPME-GC/MS). At the same storage time, unsalted wild fillets contained, in general, a higher number and abundance of volatile compounds coming from microbiological or endogenous enzymatic activity than unsalted farmed ones. The more intense the salting, the lower the number and abundance of microbiological spoilage metabolites, especially in wild samples. The appearance of oxidation metabolites only in dry-salted wild samples evidences that this kind of salting provokes a certain oxidation in these samples. The better performance of farmed than wild fillets suggests that salted farmed fillets, vacuum-packed and stored under refrigeration conditions, could be a successful alternative to diversify the presence of sea bass in the market. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Bacterial sulphate reduction and mixing processes at the Aespoe Hard Rock Laboratory indicated by groundwater δ34S isotope signatures

International Nuclear Information System (INIS)

Wallin, Bill

2011-04-01

sulphate-reducing bacteria (SRB) and groundwater mixing from shallow marine and deeper, older groundwater sources during tunnel construction. These isotope changes were likely induced by the up-coning of deeper saline water and the inflow of Baltic Sea water to an intermediate depth (e.g., 200-400 m) at Aspo. The increase in δ 34 S isotope values of dissolved SO 4 2- , peaking at +28 per mille CDT (probably due to position of the tunnel below the Baltic Sea), was accompanied by a decrease in sulphate concentration in many places and, in some samples, also by changes in bicarbonate concentration, all of which are evidence of microbial sulphate reduction

Sulphate reduction and vertical distribution of sulphate-reducing bacteria quantified by rRNA slot-blot hybridization in a coastal marine sediment

DEFF Research Database (Denmark)

Sahm, K.; MacGregor, BJ; Jørgensen, BB

1999-01-01

In the past, enumeration of sulphate-reducing bacteria (SRB) by cultivation-based methods generally contradicted measurements of sulphate reduction, suggesting unrealistically high respiration rates per cell. Here, we report evidence that quantification of SRB rRNA by slot-blot hybridization...... between 18% and 25% to the prokaryotic rRNA pool. The dominant SRB were related to complete oxidizing genera (Desulphococcus, Desulphosarcina and Desulphobacterium), while Desulpho-bacter could not be detected. The vertical profile and quantity of rRNA from SRB was compared with sulphate reduction rates......, directly above the sulphate reduction maximum. Cell numbers calculated by converting the relative contribution of SRB rRNA to the percentage of DAPI-stained cells indicated a population size for SRB of 2.4-6.1 x 10(8) cells cm(-3) wet sediment. Cellular sulphate reduction rates calculated on the basis...

Evans hole and non linear optical activity in Bis(melaminium) sulphate dihydrate: A vibrational spectral study.

Science.gov (United States)

Suresh Kumar, V R; Binoy, J; Dawn Dharma Roy, S; Marchewka, M K; Jayakumar, V S

2015-01-01

Bis(melaminium) sulphate dihydrate (BMSD), an interesting melaminium derivative for nonlinear optical activity, has been subjected to vibrational spectral analysis using FT IR and FT Raman spectra. The analysis has been aided by the Potential Energy Distribution (PED) of vibrational spectral bands, derived using density functional theory (DFT) at B3LYP/6-31G(d) level. The geometry is found to correlate well with the XRD structure and the band profiles for certain vibrations in the finger print region have been theoretically explained using Evans hole. The detailed Natural Bond Orbital (NBO) analysis of the hydrogen bonding in BMSD has also been carried out to understand the correlation between the stabilization energy of hyperconjugation of the lone pair of donor with the σ(∗) orbital of hydrogen-acceptor bond and the strength of hydrogen bond. The theoretical calculation shows that BMSD has NLO efficiency, 2.66 times that of urea. The frontier molecular orbital analysis points to a charge transfer, which contributes to NLO activity, through N-H…O intermolecular hydrogen bonding between the melaminium ring and the sulphate. The molecular electrostatic potential (MEP) mapping has also been performed for the detailed analysis of the mutual interactions between melaminium ring and sulphate ion. Copyright © 2015 Elsevier B.V. All rights reserved.

Enzymatic methods for the determination of pollution in seawater using salt resistant alkaline phosphatase from eggs of the sea urchin Strongylocentrotus intermedius

International Nuclear Information System (INIS)

Menzorova, Natalie I.; Seitkalieva, Alexandra V.; Rasskazov, Valery A.

2014-01-01

Highlights: • Alkaline phosphatase from eggs of the sea urchin (StAP) proved to be active in seawater. • Activity of StAP is inhibited by very low concentrations of heavy metal. • A test to assess sea and fresh water quality has been developed basing on StAP. • For the first time a salt resistant alkaline phosphatase has been found in eukaryote. - Abstract: A new salt resistant alkaline phosphatase from eggs of the sea urchin Strongylocentrotus intermedius (StAP) has been shown to have a unique property to hydrolyze substrate in seawater without loss of enzymatic activity. The enzyme has pH optimum at 8.0–8.5. Model experiments showed various concentrations of copper, zinc, cadmium and lead added to seawater or a standard buffer mixture to inhibit completely the enzyme activity at the concentrations of 15–150 μg/l. StAP sensitivity to the presence in seawater of metals, pesticides, detergents and oil products appears to be considerably less. Samples of seawater taken from aquatic areas of the Troitsy Bay of the Peter the Great Bay, Japan Sea have been shown to inhibit the enzyme activity; the same was shown for the samples of fresh waters. The phosphatase inhibition assay developed proved to be highly sensitive, technically easy-to use allowing to test a great number of samples

Sulphate reduction experiment: SURE-1

International Nuclear Information System (INIS)

Pedersen, K.; Arlinger, J.; Bengtsson, A.; Edlund, J.; Eriksson, L.; Hallbeck, L.; Johansson, J.; Paeaejaervi, A.; Rabe, L.

2013-11-01

It was previously concluded that opposing gradients of sulphate and methane, observations of 16S rDNA sequences displaying great similarity to those of anaerobic methane-oxidizing Archaea, and a peak in sulphide concentration in groundwater from a depth of 250-350 m in Olkiluoto, Finland, indicated proper conditions for methane oxidation with sulphate. In the present research (SURE-1), pressure-resistant, gas-tight circulating systems were constructed to enable the investigation of attached and unattached anaerobic microbial populations from a depth of 327 m in Olkiluoto under in situ pressure (2.4 MPa), diversity, dissolved gas, and hydrochemical conditions of groundwater station ONKPVA6. Three parallel flow cell cabinets were configured to allow observation of the influence on microbial metabolic activity of 11 mM methane, 11 mM methane plus 10 mM H 2 , or 2.1 mM O 2 plus 7.9 mM N 2 (i.e., air). The concentrations of these gases and of organic acids and carbon, sulphur chemistry, pH and E h , ATP, numbers of cultivable microorganisms, and total numbers of cells and bacteriophages were subsequently recorded under batch conditions for 105 d. The system containing H 2 and methane displayed microbial reduction of 0.7 mM sulphate to sulphide, while the system containing only methane produced 0.2 mM reduced sulphate. The system containing added air became inhibited and displayed no signs of microbial activity. Added H 2 and methane induced increasing numbers of lysogenic bacteriophages per cell. It appears possible that a microbial anaerobic methane-oxidizing process coupled to acetate formation and sulphate reduction may be ongoing in aquifers at a depth of 250-350 m in Olkiluoto, but clear evidence of such an AOM process was not obtained. (orig.)

Sulphate reduction experiment: SURE-1

Energy Technology Data Exchange (ETDEWEB)

Pedersen, K.; Arlinger, J.; Bengtsson, A.; Edlund, J.; Eriksson, L.; Hallbeck, L.; Johansson, J.; Paeaejaervi, A.; Rabe, L. [Microbial Analytics Sweden AB, Moelnlycke (Sweden)

2013-11-15

It was previously concluded that opposing gradients of sulphate and methane, observations of 16S rDNA sequences displaying great similarity to those of anaerobic methane-oxidizing Archaea, and a peak in sulphide concentration in groundwater from a depth of 250-350 m in Olkiluoto, Finland, indicated proper conditions for methane oxidation with sulphate. In the present research (SURE-1), pressure-resistant, gas-tight circulating systems were constructed to enable the investigation of attached and unattached anaerobic microbial populations from a depth of 327 m in Olkiluoto under in situ pressure (2.4 MPa), diversity, dissolved gas, and hydrochemical conditions of groundwater station ONKPVA6. Three parallel flow cell cabinets were configured to allow observation of the influence on microbial metabolic activity of 11 mM methane, 11 mM methane plus 10 mM H{sub 2}, or 2.1 mM O{sub 2} plus 7.9 mM N{sub 2} (i.e., air). The concentrations of these gases and of organic acids and carbon, sulphur chemistry, pH and E{sub h}, ATP, numbers of cultivable microorganisms, and total numbers of cells and bacteriophages were subsequently recorded under batch conditions for 105 d. The system containing H{sub 2} and methane displayed microbial reduction of 0.7 mM sulphate to sulphide, while the system containing only methane produced 0.2 mM reduced sulphate. The system containing added air became inhibited and displayed no signs of microbial activity. Added H{sub 2} and methane induced increasing numbers of lysogenic bacteriophages per cell. It appears possible that a microbial anaerobic methane-oxidizing process coupled to acetate formation and sulphate reduction may be ongoing in aquifers at a depth of 250-350 m in Olkiluoto, but clear evidence of such an AOM process was not obtained. (orig.)

Isotopic evolution of aqueous sulphate in northern Chile water

International Nuclear Information System (INIS)

Aravena, R.; Suzuki, O.; Fritz, P.; Pena, H.; Rauert, W.

1987-01-01

Full text: The extremely arid condition of northern Chile is the main obstacle to the present and future development of urban centres and economic activities in the region. The existing water resources are scarce. During the last decade, isotope techniques have been applied to investigate aspects such as the origin and residence time of the groundwater, these being extremely important for water development and water management. This paper presents 18 O and 34 S data in aqueous sulphate, as well as 18 O, 2 H, and 3 H from springs, rivers and groundwater samples of the Pampa del Tamarugal and Salar de Llamara basins. The principal aim of this study was to investigate the isotope evolution of the sulphate, the origin of the sulphur, the groundwater flow path, and the possibility of using the 18 O of the sulphate as a tracer for estimation of the residence time of the groundwater. Springs that have their recharge area in the high Altiplano (Salar del Huasco basin) show δ values between +5.0 per mille and +6.0 per mille for the 18 O and +5.0 per mille and +9.0 per mille for the 34 S isotope. Springs from lower altitude, show an isotope content between + 8.6 per mille and + 10.6 per mille for 18 O and +7.4 per mille and + 11.7 per mille for 34 S. The groundwaters in the Pampa aquifers, based on their hydrogen and oxygen isotope composition, are associated with different recharge areas. However, these waters show an isotope range for the sulphate similar to .he one of the springs, and no clear relationships are observed between isotope content, flow path and residence time. This pattern could be related to the poorly defined aquifer systems present in the Pampa. The Llamara groundwaters have a uniform isotope content and are the most enriched in the region (δ 18 O = -6.0 per mille and δ 2 H = -50 per mille). The isotope composition of their sulphate compares well with the Pampa groundwater, indicating a similar sulphate source. The isotope composition of gypsum

Borehole locations on seven interior salt domes

International Nuclear Information System (INIS)

Simcox, A.C.; Wampler, S.L.

1982-08-01

This report is designed as an inventory of all wells known to have been drilled within a five-mile radius of each of seven salt domes within the Interior Salt Basin in east Texas, northern Louisiana and Mississippi. There are 72 boreholes that entered salt above an elevation of -3000 feet mean sea level. For these, details of location, drilling dates, depth of casing and cement, elevation of top of caprock and salt, etc., are given on tables in the appendix. Of the seven domes, Oakwood has the largest number of boreholes, thirty-eight (including two sidetracked wells) that enter the salt stock above -3000 feet mean sea level; another dome in northeast Texas, Keechi, has eight; in northern Louisiana, Rayburn's has four and Vacherie has five; in southern Mississippi, Cypress Creek has seven, Lampton has one, and Richton has nine. In addition, all wells known outside the supra-domal area, but within a five-mile radius of the center of the 7 domes are separately catalogued

Sulphate Removal from Water by Carbon Residue from Biomass Gasification: Effect of Chemical Modification Methods on Sulphate Removal Efficiency

Directory of Open Access Journals (Sweden)

Hanna Runtti

2016-02-01

Full Text Available Sulphate removal from mine water is a problem because traditional chemical precipitation does not remove all sulphates. In addition, it creates lime sediment as a secondary waste. Therefore, an inexpensive and environmental-friendly sulphate removal method is needed in addition to precipitation. In this study, carbon residues from a wood gasification process were repurposed as precursors to a suitable sorbent for SO42- ion removal. The raw material was modified using ZnCl2, BaCl2, CaCl2, FeCl3, or FeCl2. Carbon residues modified with FeCl3 were selected for further consideration because the removal efficiency toward sulphate was the highest. Batch sorption experiments were performed to evaluate the effects of the initial pH, initial SO42- ion concentration, and contact time on sulphate removal. The removal of SO42- ions using Fe-modified carbon residue was notably higher compared with unmodified carbon residue and commercially available activated carbon. The sorption data exhibited pseudo-second-order kinetics. The isotherm analysis indicated that the sorption data of Fe-modified carbon residues can be represented by the bi-Langmuir isotherm model.

Chemical sulphate removal for treatment of construction and demolition debris leachate.

Science.gov (United States)

Kijjanapanich, Pimluck; Annachhatre, Ajit P; Esposito, Giovanni; Lens, Piet N L

2014-08-01

Construction and demolition debris (CDD) is a product of construction, renovation or demolition activities. It has a high gypsum content (52.4% of total gypsum), concentrated in the CDD sand (CDDS) fraction. To comply with the posed limit of the maximum amount of sulphate present in building sand, excess sulphate needs to be removed. In order to enable reuse of CDDS, a novel treatment process is developed based on washing of the CDDS to remove most of the gypsum, and subsequent sulphate removal from the sulphate-rich CDDS leachate. This study aims to assess chemical techniques, i.e. precipitation and adsorption, for sulphate removal from the CDDS leachate. Good sulphate removal efficiencies (up to 99.9%) from the CDDS leachate can be achieved by precipitation with barium chloride (BaCl2) and lead(II) nitrate (Pb(NO3)2). Precipitation with calcium chloride (CaCl2), calcium carbonate (CaCO3) and calcium oxide (CaO) gave less efficient sulphate removal. Adsorption of sulphate to aluminium oxide (Al2O3) yielded a 50% sulphate removal efficiency, whereas iron oxide-coated sand as adsorbent gave only poor (10%) sulphate removal efficiencies.

Uranium and sulphate values from carbonate leach process

International Nuclear Information System (INIS)

Berger, B.

1983-01-01

The process concerns the recovery of uraniferous and sulphur values from liquor resulting from the attack of sulphur containing uraniferous ores by an alkaline solution of sodium carbonate and/or bicarbonate. Ammonia is introduced into the liquor to convert any HCO 3 - to CO 3 2- . The neutralised liquor from this step is then contacted with an anion exchange resin to fix the uranium and sulphate ions, leaving a liquor containing ammonia, sodium carbonate and/or bicarbonate in solution. Uranium and sulphate ions are eluted with an ammonia carbonate and/or bicarbonate solution to yield a solution of ammonium uranyl carbonate complex and ammonium sulphate. The solution is subjected to thermal treatment until a suspension of precipitated ammonium uranate and/or diuranate is obtained in a solution of the ammonium sulphate. Carbon dioxide, ammonia and water vapor are driven off. The precipitated ammonium uranate and/or diuranate is then separated from the solution of ammonium sulphate and the precipitate is calcined to yield uranium trioxide and ammonia

Effects of livestock species and stocking density on accretion rates in grazed salt marshes

NARCIS (Netherlands)

Nolte, Stefanie; Esselink, Peter; Bakker, Jan P.; Smit, Christian

2015-01-01

Coastal ecosystems, such as salt marshes, are threatened by accelerated sea-level rise (SLR). Salt marshes deliver valuable ecosystem services such as coastal protection and the provision of habitat for a unique flora and fauna. Whether salt marshes in the Wadden Sea area are able to survive

Retrieving simulated volcanic, desert dust and sea-salt particle properties from two/three-component particle mixtures using UV-VIS polarization lidar and T matrix

Directory of Open Access Journals (Sweden)

G. David

2013-07-01

Full Text Available During transport by advection, atmospheric nonspherical particles, such as volcanic ash, desert dust or sea-salt particles experience several chemical and physical processes, leading to a complex vertical atmospheric layering at remote sites where intrusion episodes occur. In this paper, a new methodology is proposed to analyse this complex vertical layering in the case of a two/three-component particle external mixtures. This methodology relies on an analysis of the spectral and polarization properties of the light backscattered by atmospheric particles. It is based on combining a sensitive and accurate UV-VIS polarization lidar experiment with T-matrix numerical simulations and air mass back trajectories. The Lyon UV-VIS polarization lidar is used to efficiently partition the particle mixture into its nonspherical components, while the T-matrix method is used for simulating the backscattering and depolarization properties of nonspherical volcanic ash, desert dust and sea-salt particles. It is shown that the particle mixtures' depolarization ratio δ p differs from the nonspherical particles' depolarization ratio δns due to the presence of spherical particles in the mixture. Hence, after identifying a tracer for nonspherical particles, particle backscattering coefficients specific to each nonspherical component can be retrieved in a two-component external mixture. For three-component mixtures, the spectral properties of light must in addition be exploited by using a dual-wavelength polarization lidar. Hence, for the first time, in a three-component external mixture, the nonsphericity of each particle is taken into account in a so-called 2β + 2δ formalism. Applications of this new methodology are then demonstrated in two case studies carried out in Lyon, France, related to the mixing of Eyjafjallajökull volcanic ash with sulfate particles (case of a two-component mixture and to the mixing of dust with sea-salt and water-soluble particles

Coastal salt-marshes in Albania

OpenAIRE

JULIAN SHEHU; ALMA IMERI; RUDINA KOCI; ALFRED MULLAJ

2014-01-01

The salt marshes of Albania comprise a narrow belt along the Adriatic and Ionian Seas. They have been the subject of a range of human activities causing habitat loss. Enclosure for agricultural use, ports and other infrastructure has reduced many salt marshes to a narrow fringe along estuary shores. Salt marshes are important for a range of interests. In particular they support a range of specialist plant communities and associated animals (especially breeding and wintering birds) and often h...

Trace determination of heavy metal concentrations in fauna, flora and salt samples from Black Sea waters by charged particles - induced X-rays

International Nuclear Information System (INIS)

Badica, T.; Ciortea, C.; Dima, S.; Petrovici, A.; Popescu, I.; Serbanescu, O.

1977-01-01

Studies were performed on Black Sea pollution by charged particles induced X-rays spectra analysis, using alpha and 16 O beams. Fauna, flora and salt samples were analysed. We found some of the concentrations of pollutant elements to be below the accepted levels. (author)

A systematic technique for the sequential restoration of salt structures

Science.gov (United States)

Rowan, Mark G.

1993-12-01

A method is described for the sequential restoration of cross sections in areas of salt tectonics where deformation is confined to the salt and higher layers. The subsurface geometry evolves with time through the interaction of various processes: sedimentation, compaction, isostatic adjustment, thermal subsidence (if present), faulting, and salt withdrawal/ diapirism. The technique systematically calculates and removes the effects of each of these processes during specified time intervals defined by the interpreted horizons. It makes no assumptions about salt kinematics and generally results in the area of the salt layer changing through time. The method is described for restoration of extensional terranes, but it is also suitable for areas of contractional salt tectonics with only minor modifications. After converting an interpreted seismic profile to depth, the top layer is stripped off and the underlying section is decompacted according to standard porosity-depth functions. A deep baseline, unaffected by compaction or deformation, is used to restore any isostatic compensation or thermal subsidence. Isostasy is calculated according to the Airy model, and differential sedimentary loading across a section is shown to be approximately balanced by changes in salt thickness so that the load is evenly distributed. After these processes have been reversed, the resulting geometry and the seismic data are used to create the sea-floor template for structural restoration. Fault offsets are removed and the layers down to the top salt are restored to this template, while the base salt remains fixed. The resulting space between the restored top salt and the fixed base salt defines the restored salt geometry. In addition, the difference between the sea-floor template and a fixed sea level provides a measure of the change in water depth (ignoring eustatic changes in sea level). The technique is applied to an interpreted seismic profile from the eastern Green Canyon/Ewing Bank

Heterogeneous Ice Nucleation Ability of NaCl and Sea Salt Aerosol Particles at Cirrus Temperatures

Science.gov (United States)

Wagner, Robert; Kaufmann, Julia; Möhler, Ottmar; Saathoff, Harald; Schnaiter, Martin; Ullrich, Romy; Leisner, Thomas

2018-03-01

In situ measurements of the composition of heterogeneous cirrus ice cloud residuals have indicated a substantial contribution of sea salt in sampling regions above the ocean. We have investigated the heterogeneous ice nucleation ability of sodium chloride (NaCl) and sea salt aerosol (SSA) particles at cirrus cloud temperatures between 235 and 200 K in the Aerosol Interaction and Dynamics in the Atmosphere aerosol and cloud chamber. Effloresced NaCl particles were found to act as ice nucleating particles in the deposition nucleation mode at temperatures below about 225 K, with freezing onsets in terms of the ice saturation ratio, Sice, between 1.28 and 1.40. Above 225 K, the crystalline NaCl particles deliquesced and nucleated ice homogeneously. The heterogeneous ice nucleation efficiency was rather similar for the two crystalline forms of NaCl (anhydrous NaCl and NaCl dihydrate). Mixed-phase (solid/liquid) SSA particles were found to act as ice nucleating particles in the immersion freezing mode at temperatures below about 220 K, with freezing onsets in terms of Sice between 1.24 and 1.42. Above 220 K, the SSA particles fully deliquesced and nucleated ice homogeneously. Ice nucleation active surface site densities of the SSA particles were found to be in the range between 1.0 · 1010 and 1.0 · 1011 m-2 at T < 220 K. These values are of the same order of magnitude as ice nucleation active surface site densities recently determined for desert dust, suggesting a potential contribution of SSA particles to low-temperature heterogeneous ice nucleation in the atmosphere.

Remote-sensing-based analysis of landscape change in the desiccated seabed of the Aral Sea--a potential tool for assessing the hazard degree of dust and salt storms.

Science.gov (United States)

Löw, F; Navratil, P; Kotte, K; Schöler, H F; Bubenzer, O

2013-10-01

With the recession of the Aral Sea in Central Asia, once the world's fourth largest lake, a huge new saline desert emerged which is nowadays called the Aralkum. Saline soils in the Aralkum are a major source for dust and salt storms in the region. The aim of this study was to analyze the spatio-temporal land cover change dynamics in the Aralkum and discuss potential implications for the recent and future dust and salt storm activity in the region. MODIS satellite time series were classified from 2000-2008 and change of land cover was quantified. The Aral Sea desiccation accelerated between 2004 and 2008. The area of sandy surfaces and salt soils, which bear the greatest dust and salt storm generation potential increased by more than 36 %. In parts of the Aralkum desalinization of soils was found to take place within 4-8 years. The implication of the ongoing regression of the Aral Sea is that the expansion of saline surfaces will continue. Knowing the spatio-temporal dynamics of both the location and the surface characteristics of the source areas for dust and salt storms allows drawing conclusions about the potential hazard degree of the dust load. The remote-sensing-based land cover assessment presented in this study could be coupled with existing knowledge on the location of source areas for an early estimation of trends in shifting dust composition. Opportunities, limits, and requirements of satellite-based land cover classification and change detection in the Aralkum are discussed.

Non-halide sediments from the Loule diapir salt mine: characterization and environmental significance

Science.gov (United States)

Ribeiro, Carlos; Terrinha, Pedro; Andrade, Alexandre; Fonseca, Bruno; Caetano, Miguel; Neres, Marta; Font, Eric; Mirão, José; Dias, Cristina; Rosado, Lúcia; Maurer, Anne-France; Manhita, Ana

2017-04-01

The sedimentary record of the Mesozoic Algarve Basin (south Portugal) spans from the Triassic to the Lower Cretaceous. Following the initial phase of Pangaea breakup and the related continental sedimentation during the Triassic, the sedimentation evolved through transitional (Triassic-Jurassic transition) to marine (Jurassic) environments. During the Hettangian a thick sequence of evaporites deposited in the basin. Most of the occurrences of these deposits have undetermined volumes, due to the post depositional diapiric movements. At the central Algarve, under the town of Loulé, a salt wall of up to > 1 km across, > 3 km in length and > 2 km in height has been exploited for the chemical industry (Loulé Diapir - LD). Most of the sediments that constitute LD are halides (> 99% halite), the exception being a package of non-halide sediments, constituted by carbonates (dolomite and magnesite) and sulphates (anhydrite) in various proportions with a maximum thickness of 3 meters. This package has a distinctive mesoscopic aspect of three layers of approximately the same thickness, different colours and primary sedimentary structures: black-brow-grey, from bottom to top. The sediments of this package were studied with a multidisciplinary approach aiming their mineralogical and chemical characterization, the determination of the organic matter content and origin, as well as the characterization and understanding of the chemical processes that occurred during the emplacement and compression of the LD: (i) X-ray diffraction for the determination of the mineral phases present and semi-quantification using the RIR-Reference Intensity Ratio method; (ii) micro analysis of the mineralogical samples by Scanning Electron Microscopy coupled to Energy Dispersive Spectroscopy; (iii) REE content determination by ICP-MS; (iv) determination of the carbon content by CHN Elemental analysis; (v) determination of the organic matter content by elemental analysis and their composition by

NUTRITIONAL VALUE AND HEAVY METALS CONTENTS OF THE DRIED SEA CUCUMBER Stichopus vastus FROM SALEMO ISLAND, INDONESIA

Directory of Open Access Journals (Sweden)

Abdullah Rasyid

2018-01-01

Full Text Available The dried sea cucumber Stichopus vastus is one of the commercially species harvested in Indonesian waters. This study aims to highlight the nutritional value and heavy metals content of dried sea cucumber S. vastus. Proximate (moisture, ash, protein, fat and carbohydrate, mineral (sodium, calcium, potassium and iron and heavy metal (mercury, cadmium, arsenic and lead were determined by standard method of AOAC, while phosphorous was determined by spectrophotometric method. Chondroitin sulphate was determined by UPLC method, glucosamine sulphate and vitamin (A, B1, B2 and E by HPLC method. Results show that protein was the major component in proximate analysis of dried sea cucumber S. vastus in the present study. The protein content was 38.70%. Moisture, ash, fat and carbohydrate content were 19.46%, 34.04%, 0.38% and 7.42% respectively. All vitamins and heavy metals examined in this study were not detected. The sodium content was 8054.36 mg/100 g higher than other minerals. Calcium, potassium, phosphorus and iron content were 2449.9 mg/100 g, 159.77 mg/100 g, 5085.2 mg/100 g and 520.8 mg/100 g respectively. Glucosamine sulphate content was found to be 2.429 g/100 g, whereas chondroitin sulphate was found to be 1.115 g/100 g. It can therefore, be concluded that the dried sea cucumber S. vastus from Salemo Island is safe for human consumption and hence can be used as a source of food supplement in the future. Keywords: food supplement, Salemo island, Stichopus vastus

Sulphate Incorporation in Borosilicate Glasses and Melts: a Kinetic Approach

Energy Technology Data Exchange (ETDEWEB)

Lenoir, M. [CEA, DEN, Laboratoire d' etude et de Developpement de Matrices de Conditionnement, Centre de Marcoule, 30207 Bagnols-sur-Ceze (France); Physique des Mineraux et Magmas, UMR 7047, CNRS- Institut de Physique du Globe de Paris, 7 place Jussieu, 75252 Paris 05 (France); Grandjean, A. [Institut de Chimie Separative de Marcoule, UMR 5257, Laboratoire des Nanomateriaux Autoreparants, Marcoule, 30207 Bagnols-sur-Ceze (France); Dussossoy, J.L. [CEA, DEN, Laboratoire d' etude et de Developpement de Matrices de Conditionnement, Centre de Marcoule, 30207 Bagnols-sur-Ceze (France); Neuville, D.R. [Physique des Mineraux et Magmas, UMR 7047, CNRS- Institut de Physique du Globe de Paris, 7 place Jussieu, 75252 Paris 05 (France)

2008-07-01

The kinetics of sulphate departure in a sodium borosilicate melt were studied using in situ Raman spectroscopy. This technique allows the quantification of the amount of sulphate dissolved in a borosilicate glass as a function of heating time by comparison with measurements obtained by microprobe wavelength dispersive spectrometry. To quantify the sulphate content obtained with Raman spectroscopy, the integrated intensity of the sulphate band at 990 cm{sup -1} was scaled to the sum of the integrated bands between 800 and 1200 cm{sup -1}, bands that are assigned to Qn silica units on the basis of previous literature. Calibration curves were then determined for two different samples. An evaluation of the kinetics of departure of sulphate could thus be made as a function of the viscosity of the borosilicate glass, showing that the kinetics were controlled by the diffusion of sulphate and its volatilization from the melt. This experimental method allows in situ measurements of sulphate content at high temperature which cannot be obtained by any other simple technique. (authors)

Erbium Salts as Non-Toxic Catalysts Compatible with Alternative Reaction Media

Directory of Open Access Journals (Sweden)

Manuela Oliverio

2018-03-01

Full Text Available Green catalysts must be non-toxic, easy to manage, able to be recovered and reused, active under alternative reaction conditions and cheap. Erbium salts meet all the previously listed characteristics and today they are emerging as a valuable catalytic solution to a number of organic transformations needing a Lewis acid catalyst in wet conditions or under alternative heating sources. This review aims to summarize the application of erbium salts in green organic transformations, with particular emphasis on their versatility under both homogeneous and heterogeneous conditions. The erbium salts’ role in bifunctional catalysis is also presented.

Gastrointestinal tract wall visualization and distention during abdominal and pelvic multidetector CT with a neutral barium sulphate suspension: comparison with positive barium sulphate suspension and with water.

Science.gov (United States)

Oliva, M R; Erturk, S M; Ichikawa, T; Rocha, T; Ros, P R; Silverman, S G; Mortele, K J

2012-01-01

When examining patients with contrast-enhanced multidetector-row CT, we determined if the stomach and small bowel were visualized and distended better with a neutral barium sulphate suspension than with positive barium sulphate suspension or water. After obtaining approval from our institutional review board, 156 patients (women: 84; mean age: 54 yrs) with no history of gastrointestinal tract disease were randomized prospectively to receive orally either 900 ml of neutral (0.1% w/v) barium sulphate suspension (n = 53), 900 ml of positive (2.1% w/v) barium sulphate suspension (n = 53), or 900 ml of water (n = 50), prior to undergoing contrast-enhanced abdominal and pelvic multidetector-row CT. Two independent radiologists evaluated the stomach, and small bowel, for luminal distension and wall visualization, using a five point scale. Results were compared using Kruskal-Wallis and Mann-Whitney U tests. The walls of the stomach, and small bowel were visualized better in patients who were administered neutral barium sulphate suspension than those who were administered either positive barium sulphate suspension (p barium sulphate suspension, the stomach and small bowel were distended better compared to patients administered water (p barium sulphate suspension (p contrast-enhanced abdominal and pelvic multidetector-row CT, orally administered neutral barium sulphate suspension allows the gastrointestinal tract to be visualized and distended better than either positive barium sulphate suspension, or water.

Estimates of the non-market value of sea turtles in Tobago using stated preference techniques.

Science.gov (United States)

Cazabon-Mannette, Michelle; Schuhmann, Peter W; Hailey, Adrian; Horrocks, Julia

2017-05-01

Economic benefits are derived from sea turtle tourism all over the world. Sea turtles also add value to underwater recreation and convey non-use values. This study examines the non-market value of sea turtles in Tobago. We use a choice experiment to estimate the value of sea turtle encounters to recreational SCUBA divers and the contingent valuation method to estimate the value of sea turtles to international tourists. Results indicate that turtle encounters were the most important dive attribute among those examined. Divers are willing to pay over US$62 per two tank dive for the first turtle encounter. The mean WTP for turtle conservation among international visitors to Tobago was US$31.13 which reflects a significant non-use value associated with actions targeted at keeping sea turtles from going extinct. These results illustrate significant non-use and non-consumptive use value of sea turtles, and highlight the importance of sea turtle conservation efforts in Tobago and throughout the Caribbean region. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of agmatine sulphate on facial nerve injuries.

Science.gov (United States)

Surmelioglu, O; Sencar, L; Ozdemir, S; Tarkan, O; Dagkiran, M; Surmelioglu, N; Tuncer, U; Polat, S

2017-03-01

To evaluate the effect of agmatine sulphate on facial nerve regeneration after facial nerve injury using electron and light microscopy. The study was performed on 30 male Wistar albino rats split into: a control group, a sham-treated group, a study control group, an anastomosis group, and an anastomosis plus agmatine sulphate treatment group. The mandibular branch of the facial nerve was dissected, and a piece was removed for histological and electron microscopic examination. Regeneration was better in the anastomosis group than in the study control group. However, the best regeneration findings were seen in the agmatine sulphate treatment group. There was a significant difference between the agmatine group and the others in terms of median axon numbers (p Agmatine sulphate treatment with anastomosis in traumatic facial paralysis may enhance nerve regeneration.

The reducibility of sulphuric acid and sulphate in aqueous solution

International Nuclear Information System (INIS)

Grauer, R.

1991-07-01

In connection with the Swedish project for final storage of spent fuel elements it was necessary to assess whether dissolved sulphate can corrode the copper canister. A simple reaction between copper and sulphate is thermodynamically impossible, but copper can react to give copper sulphide if an additional electron donor such as iron(II) is available. The problem was extended to the more general question of the reducibility of sulphur(VI) in dilute aqueous solution. Chemical reduction of sulphate does not take place in dilute solution at temperatures below 100 o C. In experiments on the reduction of sulphates under hydrothermal conditions a reaction only takes place at temperatures above 275-300 o C. The oxidising action of sulphuric acid on metals becomes perceptible only at acid concentrations over 45-50%. In experiments on the cathodic reduction of 74% sulphuric acid the formation of hydrogen sulphide and elementary sulphur starts, depending on the current density, at 50-130 o C, and polarographic measurements suggest that the reducible species is not the hydrogen sulphate ion but molecular sulphuric acid. The resistance of copper to oxygen-free sulphuric acid up to a concentration of 60% is well-known. Numerous processes in industrial electrochemistry take place in sulphuric acid or sulphate electrolytes. The reversible metal/metal-sulphate electrodes of lead and cadmium are unstable relative to the corresponding metal sulphides. Nevertheless the reversible lead sulphate electrode does not fail from sulphide formation. All these facts confirm that sulphur(VI) in dilute solution is completely inert towards chemical reducing agents and also to cathodic reduction. Thus corrosion of copper by sulphate under final-storage conditions and in the absence of sulphate reducing bacteria can be almost certainly be ruled out. (author) 5 figs., 85 refs

Controlling Barium Sulphate Scale Deposition Problems in an unbleached Kraft Paper Mill

CSIR Research Space (South Africa)

Sithole, Bruce

2015-06-01

Full Text Available Troubleshooting of scale deposits and defects in paper samples showed that the problem was caused by barium sulphate and calcium sulphate scales. However, it was ascertained that barium sulphate was more of a concern than calcium sulphate...

Treatment with magnesium sulphate in pre-term birth

DEFF Research Database (Denmark)

Wolf, Hans; Hegaard, H K; Greisen, G

2012-01-01

Premature birth increases a child's risk of cerebral palsy and death. The aim of this work is to investigate the association between treatment with magnesium sulphate during premature deliveries and infants' cerebral palsy and mortality through a meta-analysis of observational studies....... A comprehensive search of the Cochrane Library, EMBASE and the PubMed database from their inceptions to 1 October, 2010 using the keywords 'magnesium sulphate, children/infant/pre-term/premature and cerebral palsy/mortality/morbidity/adverse effects/outcome' identified 11 reports of observational studies. Two...... authors working independently extracted the data. A meta-analysis of the data found an association between magnesium sulphate treatment and a significantly reduced risk of mortality (RR 0.73; 95% CI 0.61-0.89) and cerebral palsy (OR 0.64; 95% CI 0.47-0.89). Antenatal treatment with magnesium sulphate...

Cumulates, Dykes and Pressure Solution in the Ice-Salt Mantle of Europa: Geological Consequences of Pressure Dependent Liquid Compositions and Volume Changes During Ice-Salt Melting Reactions.

Science.gov (United States)

Day, S.; Asphaug, E.; Bruesch, L.

2002-12-01

Water-salt analogue experiments used to investigate cumulate processes in silicate magmas, along with observations of sea ice and ice shelf behaviour, indicate that crystal-melt separation in water-salt systems is a rapid and efficient process even on scales of millimetres and minutes. Squeezing-out of residual melts by matrix compaction is also predicted to be rapid on geological timescales. We predict that the ice-salt mantle of Europa is likely to be strongly stratified, with a layered structure predictable from density and phase relationships between ice polymorphs, aqueous saline solutions and crystalline salts such as hydrated magnesium sulphates (determined experimentally by, inter alia, Hogenboom et al). A surface layer of water ice flotation cumulate will be separated from denser salt cumulates by a cotectic horizon. This cotectic horizon will be both the site of subsequent lowest-temperature melting and a level of neutral buoyancy for the saline melts produced. Initial melting will be in a narrow depth range owing to increasing melting temperature with decreasing pressure: the phase relations argue against direct melt-though to the surface unless vesiculation occurs. Overpressuring of dense melts due to volume expansion on cotectic melting is predicted to lead to lateral dyke emplacement and extension above the dyke tips. Once the liquid leaves the cotectic, melting of water ice will involve negative volume change. Impact-generated melts will drain downwards through the fractured zones beneath crater floors. A feature in the complex crater Mannan'an, with elliptical ring fractures around a conical depression with a central pit, bears a close resemblance to Icelandic glacier collapse cauldrons produced by subglacial eruptions. Other structures resembling Icelandic cauldrons occur along Europan banded structures, while resurgence of ice rubble within collapse structures may produce certain types of chaos region. More general contraction of the ice mantle

Sulphate in Liquid Nuclear Waste: from Production to Containment

Energy Technology Data Exchange (ETDEWEB)

Lenoir, M.; Grandjean, A.; Ledieu, A.; Dussossoy, J.L.; Cau Dit Coumes, C.; Barre, Y.; Tronche, E. [CEA Marcoule, DEN/DTCD/SECM/LDMC, Batiment 208 BP17171, Bagnols sur Ceze, 30207 (France)

2009-06-15

Nuclear industry produces a wide range of low and intermediate level liquid radioactive wastes which can include different radionuclides such as {sup 90}Sr. In La Hague reprocessing plant and in the nuclear research centers of CEA (Commissariat a l'Energie Atomique), the coprecipitation of strontium with barium sulphate is the technique used to treat selectively these contaminated streams with the best efficiency. After the decontamination process, low and intermediate level activity wastes incorporating significant quantities of sulphate are obtained. The challenge is to find a matrix easy to form and with a good chemical durability which is able to confine this kind of nuclear waste. The current process used to contain sulphate-rich nuclear wastes is bituminization. However, in order to improve properties of containment matrices and simplify the process, CEA has chosen to supervise researches on other materials such as cements or glasses. Indeed, cements are widely used for the immobilization of a variety of wastes (low and intermediate level wastes) and they may be an alternative matrix to bitumen. Even if Portland cement, which is extensively used in the nuclear industry, presents some disadvantages for the containment of sulphate-rich nuclear wastes (risk of swelling and cracking due to delayed ettringite formation), other cement systems, such as calcium sulfo-aluminate binders, may be valuable candidates. Another matrix to confine sulphate-rich waste could be the glass. One of the advantages of this material is that it could also immobilize sulphate containing high level nuclear waste which is present in some countries. This waste comes from the use of ferrous sulfamate as a reducing agent for the conversion of Pu{sup 4+} to Pu{sup 3+} in the partitioning stage of the actinides during reprocessing. Sulphate solubility in borosilicate glasses has already been studied in CEA at laboratory and pilot scales. At a pilot scale, low level liquid waste has been

Desalination of salt damaged Obernkirchen sandstone by an applied DC field

DEFF Research Database (Denmark)

Matyščák, Ondřej; Ottosen, Lisbeth M.; Rörig-Dalgaard, Inge

2014-01-01

Soluble salts are considered as one of the most common causes for decay of building materials. In the present work, an electrokinetic method for desalination of sandstones from a historic warehouse was tested. The sandstones claddings were removed from the warehouse during a renovation action...... in the stones, i.e. the present investigation faces more challenges relevant to a real desalination action. Experiments were conducted with two Obernkirchen sandstones from the same warehouse, but with different levels of salt concentrations and porosity. The investigation includes removal of the most common...... salts: chlorides, nitrates, sulphates. In the experimental setup the electrodes were placed in a clay poultice: a mixture of kaolinite, calcite and distilled water. An electric direct current (DC) field was applied to the sandstone.By applying 2mA for 5–11days it was possible to reduce the chloride...

Post traumatic tetanus and role magnesium sulphate

International Nuclear Information System (INIS)

Sikendr, R.I.; Samad, B.U.; Memon, M.I.

2009-01-01

Tetanus is a life threatening disease. Reported mortality for tetanus is 15-39%. Conventional treatment includes heavy sedation and artificial ventilation. Complications resulting from long term heavy sedation and artificial ventilation contribute to 60% of the total mortality caused by tetanus. In this study magnesium sulphate was used to reduce the need for sedation and artificial ventilation. Objectives of this prospective study were to determine the role of magnesium sulphate in post traumatic tetanus. The study was carried out in surgical Intensive Care at Pakistan Institute of Medical Sciences (PIMS), Islamabad from Jan 2004 to Dec 2007. Forty-four patients presented during this period and 33 patients were included in the study. All patients had tracheostomy done within 48 hours. Every patient was started Magnesium Sulphate therapy for control of spasms after sending baseline investigations. Patients were given ventilatory support when needed. All data was entered in well structured proforma. SPSS-10 was used to analyse data. Thirty-three patients were included in the study and all patients were given magnesium sulphate. Out of these, 45.5% cases were grade 4 tetanus, 73.6% and 63.3% cases did not require artificial ventilation and additional sedation respectively, 51.1% patients remained free of complications of tetanus. Overall mortality was 30.3%. Use of Magnesium Sulphate is safe and reduces the need for sedation and artificial ventilation in high grade tetanus thus contributing to survival benefit in adult post-traumatic tetanus cases. (author)

The contribution of ship emissions to air pollution in the North Sea regions

Energy Technology Data Exchange (ETDEWEB)

Matthias, Volker, E-mail: volker.matthias@gkss.d [GKSS Research Centre Geesthacht, Institute for Coastal Research, Max-Planck-Strasse 1, 21502 Geesthacht (Germany); Bewersdorff, Ines [GKSS Research Centre Geesthacht, Institute for Coastal Research, Max-Planck-Strasse 1, 21502 Geesthacht (Germany); Aulinger, Armin, E-mail: armin.aulinger@gkss.d [GKSS Research Centre Geesthacht, Institute for Coastal Research, Max-Planck-Strasse 1, 21502 Geesthacht (Germany); Quante, Markus, E-mail: markus.quante@gkss.d [GKSS Research Centre Geesthacht, Institute for Coastal Research, Max-Planck-Strasse 1, 21502 Geesthacht (Germany)

2010-06-15

As a consequence of the global distribution of manufacturing sites and the increasing international division of labour, ship traffic is steadily increasing and is becoming more and more important as an origin of air pollution. This study investigates the impact of ship emissions in coastal areas of the North Sea under conditions of the year 2000 by means of a regional chemistry transport model which runs on a sufficiently high resolution to study air pollution in coastal regions. It was found that northern Germany and Denmark in summer suffer from more than 50% higher sulphate, nitrate and ammonium aerosol concentrations due to contributions from ships. The implementation of a sulphur emission control area (SECA) in the North Sea, as it was implemented at the end of 2007, directly results in reduced sulphur dioxide and sulphate aerosol concentrations while nitrate aerosol concentrations are slightly increased. - Ship emissions lead to significantly enhanced air pollution by secondary inorganic aerosols in North Sea coastal areas.

Atmospheric salt deposition in a tropical mountain rainforest at the eastern Andean slopes of south Ecuador – Pacific or Atlantic origin?

Directory of Open Access Journals (Sweden)

S. Makowski Giannoni

2016-08-01

Full Text Available Sea salt (NaCl has recently been proven to be of the utmost importance for ecosystem functioning in Amazon lowland forests because of its impact on herbivory, litter decomposition and, thus, carbon cycling. Sea salt deposition should generally decline as distance from its marine source increases. For the Amazon, a negative east–west gradient of sea salt availability is assumed as a consequence of the barrier effect of the Andes Mountains for Pacific air masses. However, this generalized pattern may not hold for the tropical mountain rainforest in the Andes of southern Ecuador. To analyse sea salt availability, we investigated the deposition of sodium (Na+ and chloride (Cl−, which are good proxies of sea spray aerosol. Because of the complexity of the terrain and related cloud and rain formation processes, sea salt deposition was analysed from both, rain and occult precipitation (OP along an altitudinal gradient over a period between 2004 and 2009. To assess the influence of easterly and westerly air masses on the deposition of sodium and chloride over southern Ecuador, sea salt aerosol concentration data from the Monitoring Atmospheric Composition and Climate (MACC reanalysis data set and back-trajectory statistical methods were combined. Our results, based on deposition time series, show a clear difference in the temporal variation of sodium and chloride concentration and Na+ ∕ Cl− ratio in relation to height and exposure to winds. At higher elevations, sodium and chloride present a higher seasonality and the Na+ ∕ Cl− ratio is closer to that of sea salt. Medium- to long-range sea salt transport exhibited a similar seasonality, which shows the link between our measurements at high elevations and the sea salt synoptic transport. Although the influence of the easterlies was predominant regarding the atmospheric circulation, the statistical analysis of trajectories and hybrid receptor models revealed a stronger impact of the

Interdependent action of nickel sulphate and X-rays on human lymphoblastoid leukeamic cells

International Nuclear Information System (INIS)

Bensimon, Jacques

1977-01-01

In a first experiment, cells were cultured in media supplemented by nickel sulphate, irradiated in same media and cultured in same media after irradiation. In a second experiment, cells were cultured during 18hrs. in media supplemented by nickel sulphate, and then cells were washed and cultured in normal media where they were irradiated. The nickel sulphate toxicity appears as a creasing function of the nickel sulphate concentration and the nickel sulphate action endurance. The nickel sulphate toxic effect is amplified by X-rays. This amplification is a time function that depends on the X-ray dose, nickel sulphate concentration and period of time from the outset of culture to the irradiation. The nickel sulphate toxic effect appears faster when nickel works after X-rays [fr

Comparative studies of bile salts. A new type of bile salt from Arapaima gigas (Cuvier) (family Osteoglossidae).

Science.gov (United States)

Haslewood, G A; Tökés, L

1972-03-01

1. Arapaima gigas bile salts were hydrolysed by alkali or cleaved with dioxan-trichloroacetic acid to give cholic acid, arapaimic acid, arapaimol-A and arapaimol-B. 2. I.r., n.m.r. and mass spectroscopy and [alpha](D) measurements indicated that arapaimic acid and arapaimol-A and -B are respectively 2alpha,3alpha,7alpha,12alpha-tetrahydroxy-5beta,25in-cholestan-26-oic acid, 5beta,25R-cholestane-2beta,3alpha,7alpha,12alpha,26-pentol and 5beta-cholestane-2beta,3alpha,7alpha,12alpha,26,27-hexol. 3. Partial synthesis of 2beta,3alpha,7alpha,12alpha-tetrahydroxy-5alpha- and -5beta-cholan-24-oic acid and their spectral examination fully confirmed these conclusions. 4. A. gigas bile salts show primitive features in that they comprise alcohol sulphates and a C(27) acid; they are also specialized in showing 2beta-hydroxylation.

Performance investigation of a salt gradient solar pond coupled with desalination facility near the Dead Sea

International Nuclear Information System (INIS)

Saleh, A.; Qudeiri, J.A.; Al-Nimr, M.A.

2011-01-01

Solar ponds provide the most convenient and least expensive option for heat storage for daily and seasonal cycles. This is particularly important for a desalination facility, if steady and constant water production is required. If, in addition to high storage capacity, other favorable conditions exist, the salt gradient solar ponds (SGSPs) are expected to be able to carry the entire load of a large-scale flash desalination plants without dependence upon supplementary sources. This paper presents a performance investigation of a SGSP coupled with desalination plant under Jordanian climatic conditions. This is particularly convenient in the Dead Sea region characterized by high solar radiation intensities, high ambient temperature most of the year, and by the availability of high concentration brine. It was found that a 3000 m 2 solar pond installed near the Dead Sea is able to provide an annual average production rate of 4.3 L min -1 distilled water compared with 3.3 L min -1 that would be produced by El Paso solar pond, which has the same surface area. Based on this study, solar ponds appear to be a feasible and an appropriate technology for water desalination near the Dead Sea in Jordan. -- Research highlights: → A performance investigation of a solar pond coupled with desalination plant. → Dead Sea area is characterized by availability of high solar radiation and brine. → The Dead Sea solar pond can provide production rate of 4.3 L min -1 . → El Paso solar pond has production rate of 3.32 L min -1 . The improvement is about 30%. → The solar pond with desalination investigated showed to be a feasible technology.

In Situ Production of Copper Oxide Nanoparticles in a Binary Molten Salt for Concentrated Solar Power Plant Applications.

Science.gov (United States)

Lasfargues, Mathieu; Stead, Graham; Amjad, Muhammad; Ding, Yulong; Wen, Dongsheng

2017-05-19

Seeding nanoparticles in molten salts has been shown recently as a promising way to improve their thermo-physical properties. The prospect of such technology is of interest to both academic and industrial sectors in order to enhance the specific heat capacity of molten salt. The latter is used in concentrated solar power plants as both heat transfer fluid and sensible storage. This work explores the feasibility of producing and dispersing nanoparticles with a novel one pot synthesis method. Using such a method, CuO nanoparticles were produced in situ via the decomposition of copper sulphate pentahydrate in a KNO₃-NaNO₃ binary salt. Analyses of the results suggested preferential disposition of atoms around produced nanoparticles in the molten salt. Thermal characterization of the produced nano-salt suspension indicated the dependence of the specific heat enhancement on particle morphology and distribution within the salts.

Climatology of salt transitions and implications for stone weathering.

Science.gov (United States)

Grossi, C M; Brimblecombe, P; Menéndez, B; Benavente, D; Harris, I; Déqué, M

2011-06-01

This work introduces the notion of salt climatology. It shows how climate affects salt thermodynamic and the potential to relate long-term salt damage to climate types. It mainly focuses on specific sites in Western Europe, which include some cities in France and Peninsular Spain. Salt damage was parameterised using the number of dissolution-crystallisation events for unhydrated (sodium chloride) and hydrated (sodium sulphate) systems. These phase transitions have been calculated using daily temperature and relative humidity from observation meteorological data and Climate Change models' output (HadCM3 and ARPEGE). Comparing the number of transitions with meteorological seasonal data allowed us to develop techniques to estimate the frequency of salt transitions based on the local climatology. Results show that it is possible to associate the Köppen-Geiger climate types with potential salt weathering. Temperate fully humid climates seem to offer the highest potential for salt damage and possible higher number of transitions in summer. Climates with dry summers tend to show a lesser frequency of transitions in summer. The analysis of temperature, precipitation and relative output from Climate Change models suggests changes in the Köppen-Geiger climate types and changes in the patterns of salt damage. For instance, West Europe areas with a fully humid climate may change to a more Mediterranean like or dry climates, and consequently the seasonality of different salt transitions. The accuracy and reliability of the projections might be improved by simultaneously running multiple climate models (ensembles). Copyright © 2011 Elsevier B.V. All rights reserved.

Dynamic structure mediates halophilic adaptation of a DNA polymerase from the deep-sea brines of the Red Sea.

Science.gov (United States)

Takahashi, Masateru; Takahashi, Etsuko; Joudeh, Luay I; Marini, Monica; Das, Gobind; Elshenawy, Mohamed M; Akal, Anastassja; Sakashita, Kosuke; Alam, Intikhab; Tehseen, Muhammad; Sobhy, Mohamed A; Stingl, Ulrich; Merzaban, Jasmeen S; Di Fabrizio, Enzo; Hamdan, Samir M

2018-01-24

The deep-sea brines of the Red Sea are remote and unexplored environments characterized by high temperatures, anoxic water, and elevated concentrations of salt and heavy metals. This environment provides a rare system to study the interplay between halophilic and thermophilic adaptation in biologic macromolecules. The present article reports the first DNA polymerase with halophilic and thermophilic features. Biochemical and structural analysis by Raman and circular dichroism spectroscopy showed that the charge distribution on the protein's surface mediates the structural balance between stability for thermal adaptation and flexibility for counteracting the salt-induced rigid and nonfunctional hydrophobic packing. Salt bridge interactions via increased negative and positive charges contribute to structural stability. Salt tolerance, conversely, is mediated by a dynamic structure that becomes more fixed and functional with increasing salt concentration. We propose that repulsive forces among excess negative charges, in addition to a high percentage of negatively charged random coils, mediate this structural dynamism. This knowledge enabled us to engineer a halophilic version of KOD DNA polymerase.-Takahashi, M., Takahashi, E., Joudeh, L. I., Marini, M., Das, G., Elshenawy, M. M., Akal, A., Sakashita, K., Alam, I., Tehseen, M., Sobhy, M. A., Stingl, U., Merzaban, J. S., Di Fabrizio, E., Hamdan, S. M. Dynamic structure mediates halophilic adaptation of a DNA polymerase from the deep-sea brines of the Red Sea.

Dynamic structure mediates halophilic adaptation of a DNA polymerase from the deep-sea brines of the Red Sea

KAUST Repository

Takahashi, Masateru; Takahashi, Etsuko; Joudeh, Luay I.; Marini, Monica; Das, Gobind; Elshenawy, Mohamed; Akal, Anastassja; Sakashita, Kosuke; Alam, Intikhab; Tehseen, Muhammad; Sobhy, Mohamed Abdelmaboud; Stingl, Ulrich; Merzaban, Jasmeen; Di Fabrizio, Enzo M.; Hamdan, Samir

2018-01-01

The deep-sea brines of the Red Sea are remote and unexplored environments characterized by high temperatures, anoxic water, and elevated concentrations of salt and heavy metals. This environment provides a rare system to study the interplay between halophilic and thermophilic adaptation in biologic macromolecules. The present article reports the first DNA polymerase with halophilic and thermophilic features. Biochemical and structural analysis by Raman and circular dichroism spectroscopy showed that the charge distribution on the protein’s surface mediates the structural balance between stability for thermal adaptation and flexibility for counteracting the salt-induced rigid and nonfunctional hydrophobic packing. Salt bridge interactions via increased negative and positive charges contribute to structural stability. Salt tolerance, conversely, is mediated by a dynamic structure that becomes more fixed and functional with increasing salt concentration. We propose that repulsive forces among excess negative charges, in addition to a high percentage of negatively charged random coils, mediate this structural dynamism. This knowledge enabled us to engineer a halophilic version of KOD DNA polymerase.—Takahashi, M., Takahashi, E., Joudeh, L. I., Marini, M., Das, G., Elshenawy, M. M., Akal, A., Sakashita, K., Alam, I., Tehseen, M., Sobhy, M. A., Stingl, U., Merzaban, J. S., Di Fabrizio, E., Hamdan, S. M. Dynamic structure mediates halophilic adaptation of a DNA polymerase from the deep-sea brines of the Red Sea.

Dynamic structure mediates halophilic adaptation of a DNA polymerase from the deep-sea brines of the Red Sea

KAUST Repository

Takahashi, Masateru

2018-01-24

The deep-sea brines of the Red Sea are remote and unexplored environments characterized by high temperatures, anoxic water, and elevated concentrations of salt and heavy metals. This environment provides a rare system to study the interplay between halophilic and thermophilic adaptation in biologic macromolecules. The present article reports the first DNA polymerase with halophilic and thermophilic features. Biochemical and structural analysis by Raman and circular dichroism spectroscopy showed that the charge distribution on the protein’s surface mediates the structural balance between stability for thermal adaptation and flexibility for counteracting the salt-induced rigid and nonfunctional hydrophobic packing. Salt bridge interactions via increased negative and positive charges contribute to structural stability. Salt tolerance, conversely, is mediated by a dynamic structure that becomes more fixed and functional with increasing salt concentration. We propose that repulsive forces among excess negative charges, in addition to a high percentage of negatively charged random coils, mediate this structural dynamism. This knowledge enabled us to engineer a halophilic version of KOD DNA polymerase.—Takahashi, M., Takahashi, E., Joudeh, L. I., Marini, M., Das, G., Elshenawy, M. M., Akal, A., Sakashita, K., Alam, I., Tehseen, M., Sobhy, M. A., Stingl, U., Merzaban, J. S., Di Fabrizio, E., Hamdan, S. M. Dynamic structure mediates halophilic adaptation of a DNA polymerase from the deep-sea brines of the Red Sea.

Mesophilic and thermophilic anaerobic digestion of sulphate-containing wastewaters.

Science.gov (United States)

Colleran, E; Pender, S

2002-01-01

The effect of sulphate at an influent chemical oxygen demand (COD):sulphate ratio of 4 on the operational performance of anaerobic hybrid reactors treating molasses wastewater was investigated under mesophilic and thermophilic conditions in a long-term laboratory-scale study over a 1,081 day period. The presence of sulphate reduced the COD removal efficiency under both mesophilic and thermophilic conditions. At 55 degrees C, effluent acetate levels were consistently greater than 4000 mg l(-1) indicating that thermophilic acetate-utilising methane-producing bacteria (MPB) or sulphate-reducing bacteria (SRB) had not developed in the reactor under the conditions applied. At 37 degrees C, acetate was exclusively utilised by acetoclastic methanogens, whereas H2-utilising SRB predominated over H2-utilising MPB in the competition for hydrogen. By contrast, hydrogenotrophic MPB were shown to outcompete H2-utilising SRB during long-term thermophilic operation. 16SrDNA analysis of the seed sludge and reactor biomass on conclusion of the 37 degrees C and 55 degrees C trials illustrated that the dominant methanogen present on conclusion of the thermophilic trial in the absence of influent sulphate was related to Methanocorpusculum parvuum, and was capable of growth on both acetate and hydrogen. By contrast, an organism closely related to Methanobacterium thermoautotrophicum was the dominant methanogen present in the sulphate-fed reactor on completion of the thermophilic trial.

An 131I iodotamoxifen: no carrier added iodination via a diazonium salt

International Nuclear Information System (INIS)

Hunter, D.H.; Strickland, L.A.

1986-01-01

An 131 I-labeled iodotamoxifen has been prepared by a ''no carrier added'' procedure in a 40% radiochemical yield via an aryl diazonium ion salt intermediate. Two approaches were used to produce high specific activity iodotamoxifen: nonaqueous solvents and copper catalysis. The use of the nonaqueous solvent acetonitrile has proved successful while neither copper powder, copper-bronze, copper(I)oxide nor Cu(II) sulphate showed any catalytic effects. (author)

Physicochemical studies on Uburu Salt Lake Ebonyi State-Nigeria.

Science.gov (United States)

Akubugwo, I E; Ofoegbu, C J; Ukwuoma, C U

2007-09-15

Physicochemical properties of soil (sediment) and water from Uburu salt lake were evaluated and compared with control soil and surface water from the same community. Results showed significant (p copper, lead and zinc in the lake water relative to the control. The values of these metals in the lake soil (sediments) however, were significantly (p potassium, nitrate, carbonate, sulphate and phosphate levels compared to the control. Significant (p < 0.05) changes were also noted in the lake soil's pH, exchangeable acidity, nitrogen, organic carbon, calcium and magnesium levels. Also the soil texture was affected relative to the control. In a number of cases, the values of the studied parameters were higher than the permissible WHO standards. In view of these findings, cautious use of the salt lake soil and water is advocated.

LEVERAGING TREATMENT OF SALT ATTACK AND RISING DAMP IN HERITAGE BUILDINGS IN PENANG, MALAYSIA

Directory of Open Access Journals (Sweden)

Haris Fadzilah Abdul Rahman

2010-06-01

Full Text Available Of the common building defects that occur in heritage buildings in Penang, Malaysia, salt attack and rising damp are considered the most challenging, particularly for building conservation. The problem of salt attack is closely associated with rising damp. Moisture from the rising damp makes the building’s existing salts soluble, or ground water that contains salt finds its way through the building wall. This moisture then evaporates on or just below the wall’s surface, leaving salt residue behind. High salt concentrations in masonry walls cause extensive fretting and crumbling of the lower parts of walls. These formations gradually contribute to building dilapidation and reduce the building’s aesthetic value. Sodium chloride and calcium sulphate are commonly found in masonry walls, apart from other forms of salts. The sources of these salts may be natural or manmade. This paper is based on research into the problems of salt attack and rising damp in heritage masonry buildings in Penang, Malaysia. Based on a case study of five buildings in Penang, the research findings showed that these buildings faced several common building defects, including salt attack and rising damp. Treatment guidelines for salt attack and rising damp are proposed within the Malaysian context of architectural heritage and climatic conditions.

Sea Spray Aerosols

DEFF Research Database (Denmark)

Butcher, Andrew Charles

emissions produced directly from bubble bursting as the result of air entrainment from breaking waves and particles generated from secondary emissions of volatile organic compounds. In the first paper, we study the chemical properties of particles produced from several sea water proxies with the use...... of a cloud condensation nuclei ounter. Proxy solutions with high inorganic salt concentrations and some organics produce sea spray aerosol particles with little change in cloud condensation activity relative to pure salts. Comparison is made between a frit based method for bubble production and a plunging...... a relationship between plunging jet particle ux, oceanic particle ux, and energy dissipation rate in both systems. Previous sea spray aerosol studies dissipate an order of magnitude more energy for the same particle ux production as the open ocean. A scaling factor related to the energy expended in air...

Spatial-temporal dynamics of chemical composition of surface snow in East Antarctica along the Progress station-Vostok station transect

Science.gov (United States)

Khodzher, T. V.; Golobokova, L. P.; Osipov, E. Yu.; Shibaev, Yu. A.; Lipenkov, V. Ya.; Osipova, O. P.; Petit, J. R.

2014-05-01

In January of 2008, during the 53rd Russian Antarctic Expedition, surface snow samples were taken from 13 shallow (0.7 to 1.5 m depth) snow pits along the first tractor traverse from Progress to Vostok stations, East Antarctica. Sub-surface snow/firn layers are dated from 2.1 to 18 yr. The total length of the coast to inland traverse is more than 1280 km. Here we analysed spatial variability of concentrations of sulphate ions and elements and their fluxes in the snow deposited within the 2006-2008 time interval. Anions were analysed by high-performance liquid chromatography (HPLC), and the determination of selected metals, including Na, K, Mg, Ca and Al, was carried out by mass spectroscopy with atomization by induced coupled plasma (ICP-MS). Surface snow concentration records were examined for trends versus distance inland, elevation, accumulation rate and slope gradient. Na shows a significant positive correlation with accumulation rate, which decreases as distance from the sea and altitude increase. K, Ca and Mg concentrations do not show any significant relationship either with distance inland or with elevation. Maximal concentrations of these elements with a prominent Al peak are revealed in the middle part of the traverse (500-600 km from the coast). Analysis of element correlations and atmospheric circulation patterns allow us to suggest their terrestrial origin (e.g. aluminosilicates carried as a continental dust) from the Antarctic nunatak areas. Sulphate concentrations show no significant relationship with distance inland, elevation, slope gradient and accumulation rate. Non-sea salt secondary sulphate is the most important contribution to the total sulphate budget along the traverse. Sulphate of volcanic origin attributed to the Pinatubo eruption (1991) was revealed in the snow pit at 1276 km (depth 120-130 cm).

Effects of the North Atlantic Oscillation and wind waves on salt marsh dynamics in the Danish Wadden Sea

DEFF Research Database (Denmark)

Kim, Daehyun; Grant, William E.; Cairns, David M.

2013-01-01

Long-term eustatic sea-level variation has been recognized as a primary factor affecting the hydrological and geomorphic dynamics of salt marshes. However, recent studies suggest that wind waves influenced by atmospheric oscillations also may play an important role in many coastal areas. Although...... this notion has been conceptually introduced for the Wadden Sea, no modeling attempts have been made yet. As a proof of concept, this study developed a simulation model using the commercially available STELLAA (R) software, based on long-term data on water level and sedimentation collected at a back......-barrier marsh on the Skallingen peninsula in Denmark. In the model, the frequency (number year(-1)) of wind-driven extreme high water level (HWL) events (> 130 cm Danish Ordnance Zero) was simulated in terms of the North Atlantic Oscillation (NAO) index. Then, surface accretion (cm year(-1)) and submergence...

Are high rates of sulphate reduction associated with anaerobic oxidation of methane

Energy Technology Data Exchange (ETDEWEB)

Devol, A H; Ahmed, S I

1981-01-01

Classical models of sulphur diagenesis in marine sediments are based on the assumption that the rate of sulphate reduction is first order with respect to oxidizable particulate organic carbon (POC). This assumption requires that oxidizable POC, sulphate concentration and the sulphate reduction rate be highest at the top of the sulphate reduction zone and decrease exponentially with increasing sediment depth. However, to explain recent observations of concave upwards methane distributions, the anaerobic consumption of methane has been proposed. Furthermore, it has been proposed that this consumption takes place near the bottom of the sulphate reducing zone where sulphate concentrations are low. Thus, if sulphate reducing bacteria are associated with the anaerobic oxidation of methane, a peak in sulphate reduction rate might be expected in this deep consumption zone. The importance of the process in sedimentary sulphur diagenesis is indicated by calculations estimating that 30 to 75% of the downward sulphate flux at depth may be consumed by methane oxidation within this zone. We present here profiles of sulphate reduction rate in anoxic sediments that show distinct local maxima at the depth where the anaerobic oxidation of methane would be expected. Our measurements were made during July and August 1978 in Saanich Inlet, an anoxic fjord located on the south-east of Vancouver Island, British Columbia. The inlet has a shallow sill (approx 70 m) which restricts circulation of the deeper water (maximum depth 225 m) inside the basin to the extent that for about 8 months of the year the bottom waters contain hydrogen sulphide, the inlet is an ideal location for studying sedimentary sulphate reduction because reactions with oxygen and the effects of burrowing organisms can be neglected.

Cum grano salis - NAA of selected salts

International Nuclear Information System (INIS)

Steinhauser, G.; Sterba, J.H.; Poljanc, K.; Bichler, M.; Buchtela, K.

2006-01-01

The aim of this study was to investigate the trace element concentrations of salt samples from different regions, in particular Austria, Germany, Pakistan, Poland, Switzerland, and Ukraine. Investigated types of salt were Rock-, Sea-, Lake-, and Evaporated Salt. The main objective was to find out whether the consumption of salt can contribute significantly to the daily human requirements of trace elements. Therefore, trace element concentrations in the untreated samples were compared to those of specially treated samples, simulating digestive uptake using a simple model. Salt is a non-trivial matrix for Neutron Activation Analysis (NAA) because of very high background activities from 38 Cl and 24 Na, as well as the bremsstrahlung of 32 P (originating from 35 Cl(n,α) 32 P). Because of this fact, detection limits in salt are higher compared to other matrices. Nevertheless, several elements could be detected, namely Al, Ba, Br, (Ca), Ce, Cl, Co, Cr, Cs, Eu, Fe, Hf, La, Mn, Na, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Th, and Zn, some of them only in single samples. In most samples the concentrations of trace elements in salt were too low to show biological effects. Salt can therefore only significantly contribute the essential elements sodium, chlorine, and, if added on purpose, fluorine and iodine to human nutrition. The contribution of all other traces in salt to the average daily human requirements can be neglected. Thus, from an analytical point of view, there is no health reason to use unpurified salt. There are, however, a few drawbacks to the use of unpurified salt, as hygroscopic compounds like MgCl 2 , and even toxic heavy metals like chromium or thorium. Especially rare earth element (REE) concentrations can often be used to obtain a chemical fingerprint, which can be used to identify the origin of an unknown sample. In the case of this study, the sample number from each region was too small to collect significant data. Therefore more analytical information is needed

Improvement of seawater salt quality by hydro-extraction and re-crystallization methods

Science.gov (United States)

Sumada, K.; Dewati, R.; Suprihatin

2018-01-01

Indonesia is one of the salt producing countries that use sea water as a source of raw materials, the quality of salt produced is influenced by the quality of sea water. The resulting average salt quality contains 85-90% NaCl. The Indonesian National Standard (SNI) for human salt’s consumption sodium chloride content is 94.7 % (dry base) and for industrial salt 98,5 %. In this study developed the re-crystallization without chemical and hydro-extraction method. The objective of this research to choose the best methods based on efficiency. The results showed that re-crystallization method can produce salt with NaCl content 99,21%, while hydro-extraction method content 99,34 % NaCl. The salt produced through both methods can be used as a consumption and industrial salt, Hydro-extraction method is more efficient than re-crystallization method because re-crystallization method requires heat energy.

Sulphate issues and learning for secondary loop system at Dayabay Nuclear Power Plant

International Nuclear Information System (INIS)

Wang Changchun; Fang Jun; Yao Xuehong; He Yanhong; Chen Bin

2014-01-01

Dayabay NPP started up from 1994. There is no condensate polishing system (CPP) with initial design. Unfortunately there happened few times serious issues with sea water leakage into condensate. It was reconstructed and be added CPP from 1997. But we found sulphate concentration in SG will increased after ATE was put into operating, when CPP was out of service, then sulphate concentration decreased. Through the study and research for a few years, we found the root cause and we took these following improvements at site step by step, steam generation blow down water quality was significantly improved: Optimize feed water distribution condition in resin bed. Since the shortcomings of resin bed design, resin is moving up and down during operating. To prevent resin re-separation and broken issue, we improved the structure of feed distribution and better the resin condition in resin bed; Optimize regeneration process. Optimize mixed bed resin transferring, separation, regeneration process, re-separation and re-mixing process during regeneration; Optimize operating process. Regular clean resin beads under the water chamber and resin trap to prevent resin leak into SG system; Other actions. Check nozzles one by one in resin bed and change these nozzles with shortcomings to prevent resin leakage into resin chamber. Upgrade cation resin type from 12% DVB to 16% DVB. According to Dayabay nuclear power plant steam generator sulphate issue experience, now in China we have improved a lot for the secondary loop condensate polishing system design, equipment manufacturing, operation process, etc. We have achieved good results in our new projects such as LingAo Phase II nuclear power plant. (author)

Studies on the sorption behaviours of Th(IV) and U(VI) from aqueous sulphate solutions using impregnated resin

International Nuclear Information System (INIS)

Khatab, A.F.; Sheta, M.E.; Mahfouz, M.G.; Tolba, A.A.

2007-01-01

The sorption behaviours of thorium (IV) and uranium (VI) from aqueous sulphate solutions have been studied using n-dodecylamine and tri-n-octylamine (TOA) dissolved in benzene and impregnated onto amberlite XAD-4 (styrene-divinyl benzene copolymer). The sorption behaviours were evaluated as a function of free acidity, salting out effect, ph value, equilibrium time, V/m ratio, initial metal ion concentration, loaded amine concentration and sorption temperature. The equilibrium time for Th(IV) and U(VI) sorption from aqueous sulphate solution was found to be 90 and 60 minutes, respectively. The sorption of Th(IV) was quantitatively at ph range 3.7-4.3 and at 4.3-5.2 for U(VI). The sorption capacity of the impregnated resin was determined by batch method and it was found to be 0.031 and 0.033 mmol/g for Th(IV) and U(VI), respectively. Elution of Th(IV) from thorium-loaded impregnated resin was quantitatively achieved by using 2 mol/l HNO 3 and by using 0.1 mol/l HCl for U(VI)

THERMOCHEMISTRY OF INTERACTION REACTIONS FOR SODIUM AND ALUMINUM SULPHATES WITH COMPONENTS OF HYDRATING PORTLAND CEMENT

Directory of Open Access Journals (Sweden)

P. I. Yukhnevskiy

2018-01-01

Full Text Available Chemical additives are widely used in the technology of concrete with the purpose to solve various problems and sulphate-containing additives-electrolytes are also used as accelerators for setting and hardening of cement. Action mechanism of additive accelerators for setting and hardening of cement is rather complicated and can not be considered as well-established. An influence of sulfate-containing additives such as sodium sulfate is reduced to acceleration of cement silicate phase hydration by increasing ionic strength of the solution. In addition to it, exchange reactions of anion additive with portlandite phase (Ca(OH2 and aluminate phases of hardening cement have a significant effect on hardening process that lead to formation of readily soluble hydroxides and hardly soluble calcium salts. The influence of sulfate-containing additives on properties of water cement paste and cement stone is quite diverse and depends on salt concentration and cation type. For example, the action of the aluminum sulphate additive becomes more complicated if the additive is subjected to hydrolysis in water, which is aggravated in an alkaline medium of the water cement paste. Formation of hydrolysis products and their reaction with aluminate phases and cement portlandite lead to a significant acceleration of setting. Thus, despite the similarity of additives ensuring participation of anions in the exchange reactions, the mechanism of their influence on cement setting and hardening varies rather significantly. The present paper considers peculiar features concerning the mechanism of interaction of sodium and aluminum sulfate additives in cement compositions from the viewpoint of thermochemistry. Thermochemical equations for reactions of sulfate-containing additives with phases of hydrated cement clinker have been given in the paper. The paper contains description how to calculate thermal effects of chemical reactions and determine an influence of the formed

Observations of brine plumes below melting Arctic sea ice

Directory of Open Access Journals (Sweden)

A. K. Peterson

2018-02-01

Full Text Available In sea ice, interconnected pockets and channels of brine are surrounded by fresh ice. Over time, brine is lost by gravity drainage and flushing. The timing of salt release and its interaction with the underlying water can impact subsequent sea ice melt. Turbulence measurements 1 m below melting sea ice north of Svalbard reveal anticorrelated heat and salt fluxes. From the observations, 131 salty plumes descending from the warm sea ice are identified, confirming previous observations from a Svalbard fjord. The plumes are likely triggered by oceanic heat through bottom melt. Calculated over a composite plume, oceanic heat and salt fluxes during the plumes account for 6 and 9 % of the total fluxes, respectively, while only lasting in total 0.5 % of the time. The observed salt flux accumulates to 7.6 kg m−2, indicating nearly full desalination of the ice. Bulk salinity reduction between two nearby ice cores agrees with accumulated salt fluxes to within a factor of 2. The increasing fraction of younger, more saline ice in the Arctic suggests an increase in desalination processes with the transition to the new Arctic.

Observations of brine plumes below melting Arctic sea ice

Science.gov (United States)

Peterson, Algot K.

2018-02-01

In sea ice, interconnected pockets and channels of brine are surrounded by fresh ice. Over time, brine is lost by gravity drainage and flushing. The timing of salt release and its interaction with the underlying water can impact subsequent sea ice melt. Turbulence measurements 1 m below melting sea ice north of Svalbard reveal anticorrelated heat and salt fluxes. From the observations, 131 salty plumes descending from the warm sea ice are identified, confirming previous observations from a Svalbard fjord. The plumes are likely triggered by oceanic heat through bottom melt. Calculated over a composite plume, oceanic heat and salt fluxes during the plumes account for 6 and 9 % of the total fluxes, respectively, while only lasting in total 0.5 % of the time. The observed salt flux accumulates to 7.6 kg m-2, indicating nearly full desalination of the ice. Bulk salinity reduction between two nearby ice cores agrees with accumulated salt fluxes to within a factor of 2. The increasing fraction of younger, more saline ice in the Arctic suggests an increase in desalination processes with the transition to the new Arctic.

A Nucleus-localized Long Non-Coding RNA Enhances Drought and Salt Stress Tolerance

KAUST Repository

Qin, Tao

2017-09-09

Long non-coding RNAs (lncRNAs) affect gene expression through a wide range of mechanisms and are considered as important regulators in many essential biological processes. A large number of lncRNA transcripts have been predicted or identified in plants in recent years. However, the biological functions for most of them are still unknown. In this study, we identified an Arabidopsis thaliana lncRNA, Drought induced RNA (DRIR), as a novel positive regulator of plant response to drought and salt stress. DRIR was expressed at a low level under non-stress conditions but can be significantly activated by drought and salt stress as well as by abscisic acid (ABA) treatment. We identified a T-DNA insertion mutant, drirD, which had higher expression of the DRIR gene than the wild type plants. The drirD mutant exhibits increased tolerance to drought and salt stress. Overexpressing DRIR in Arabidopsis also increased tolerance to drought and salt stress of the transgenic plants. The drirD mutant and the overexpressing seedlings are more sensitive to ABA than the wild type in stomata closure and seedling growth. Genome-wide transcriptome analysis demonstrated that the expression of a large number of genes was altered in drirD and the overexpressing plants. These include genes involved in ABA signaling, water transport and other stress-relief processes. Our study reveals a mechanism whereby DRIR regulates plant response to abiotic stress by modulating the expression of a series of genes involved in stress response.

In-situ survey of decaying azulejos panels and the presence of salts

Directory of Open Access Journals (Sweden)

Lurdes Esteves

2016-01-01

Full Text Available Pattern or figurative azulejos are commonly found decorating the interior of churches, palaces and religious buildings in Portugal, representing local productions from the late 16th century onwards. But not every azulejo reached the present day in good condition.. The aim of this research was the survey of in situ forms of degradation, aimed at eventually establishing a relation between the occurrence of soluble salts and decay. Salt samples and small fragments collected in situ were analysed with a scanning electron microscope with microanalysis unit (SEM-EDS for the identification of saline specimens. NaCl was more abundantly found in near-shore properties, along with trona. Magnesium and calcium sulphate were more common in inland properties.

Computerised analysis of sulphate action on model concrete piles

Digital Repository Service at National Institute of Oceanography (India)

Deshmukh, A.M.; Balasubramanian, S.; Venugopal, C.

Sulphate action severely affects the durability of marine structures. It is imperative to study precisely the effects of magnesium sulphate on pile foundations in the marine environment. In the present paper an attempt is made to assess and analyse...

In Situ Production of Copper Oxide Nanoparticles in a Binary Molten Salt for Concentrated Solar Power Plant Applications

Directory of Open Access Journals (Sweden)

Mathieu Lasfargues

2017-05-01

Full Text Available Seeding nanoparticles in molten salts has been shown recently as a promising way to improve their thermo-physical properties. The prospect of such technology is of interest to both academic and industrial sectors in order to enhance the specific heat capacity of molten salt. The latter is used in concentrated solar power plants as both heat transfer fluid and sensible storage. This work explores the feasibility of producing and dispersing nanoparticles with a novel one pot synthesis method. Using such a method, CuO nanoparticles were produced in situ via the decomposition of copper sulphate pentahydrate in a KNO3-NaNO3 binary salt. Analyses of the results suggested preferential disposition of atoms around produced nanoparticles in the molten salt. Thermal characterization of the produced nano-salt suspension indicated the dependence of the specific heat enhancement on particle morphology and distribution within the salts.

Bacterial sulphate reduction and the development of alkalinity. II. Laboratory experiments with soils

Energy Technology Data Exchange (ETDEWEB)

Abd-El-Malek, Y; Rizk, S G

1963-01-01

In waterlogged soils sulphate reduction was characterized by increases in counts of sulphate reducers, and increase in titratable alkalinity, insoluble carbonate, and soluble sulphides, and a decrease in soluble Ca/sup 2 +/ + Mg/sup 2 +/. Presence of organic matter greatly enhanced sulphate reduction. A linear relationship between the amount of sulphate reduced and increases in titratable alkalinity and insoluble carbonate were apparent. The potential effects of sulphate reduction on soil fertility through the development of alkalinity are discussed.

Safety and efficacy of Bolus administration of magnesium sulphate ...

African Journals Online (AJOL)

Safety and efficacy of Bolus administration of magnesium sulphate for preeclampsia. ... On-going research is addressing its administration in terms of dosage, duration and safety. Objective: We evaluated a ... Keywords: safety, efficacy, bolus magnesium sulphate, preeclampsia, University of Benin Teaching Hospital

Kinetics and mechanism of protection of thymine from sulphate ...

Indian Academy of Sciences (India)

Unknown

The rate constant of sulphate radical anion with caffeic acid has been ... transfer of radical sites from base moiety to sugar moiety. Strand ... titrated with a standard ceric ammonium sulphate solution as reported by Kapoor et al.7. At room ...

On the salt transport in the Cananéia sea during a spring tide experiment

Directory of Open Access Journals (Sweden)

Luiz Bruner de Miranda

1996-01-01

Full Text Available Observations of the velocity, salinity, water depths and tides in the southem region of the Cananéia Sea were sampled at an anchored station during two complete tidal cycles. The measurements were made during spring tides on 5-6 December, 1991. The observed non-tidal current profile for this weakly stratified tidal channel is found to be in close agreement with the results of a simple steady state unidimensional analytical model of a well-nuxed estuary. This comparison indicates that the primary driving mechanisms are the longitudinal salinity gradient and the fresh water discharge. The contribution to the advective salt transport is dominateô by the freshwater discharge through the down-stream non-tidal flow and the up-stream dispersive term due to Stokes wave transporto This dispersive term is almost one order of magnitude smaller than the down-stream non-tidãl transport inôuced bythe fresh water discharge. TidaI correlation, acting as a counter-dispersion term, and the steady shear dispersion term are two orders of magnitude smaller than the ôown-stream salt transporto The remaining dispersive terms, which are dependent on the deviations from the mean deptb, are smaller than eitlier of these terms by one order of magnitude. The computed total salt transport per unit width of a section perpendicular to the mean flow was in close agreement (within 12 % with the sum of the individual advective and dispersive terms. On the assumption that the tidal channel sampled is laterally homogeneous, an imoalance of the salt budget across the section was observed.Observações de velocidade, de salinidade, de profundidade e de maré na região sul do Mar de Cananéia foram realizadas numa estação fixa durante dois ciclos completos de maré. Essas medidas foram feitas durante maré de sizígia, no período de 5 a 6 de dezem6ro de 1991. A exame comparativo do perfil estacionário de velocidade desse sistema fracamente estratificado, indicou boa concord

Sulphonated metal phthalocyanine complexes as redox indicators in micro titrations with cerium(IV) sulphate

Energy Technology Data Exchange (ETDEWEB)

Gowda, H S; Achar, B N [Mysore Univ. (India). Dept. of Chemistry

1980-01-01

Tetrasodium salts of copper(II) 4,4', 4'', 4'''-tetrasulphophthalocyanine 2-hydrate, nickel(II) 4,4', 4'', 4'''-tetrasulphophthalocyanine, nickel(II) 3,3', 3'', 3'''-tetrasulphophthalocyanine and cobalt(II) 4,4', 4'', 4'''-tetrasulphophthalocyanine 2-hydrate, and copper phthalocyanine trisulphonic acid are prepared in pure state. The molar absorptivity and formal redox potentials of the complexes are determined. The complexes are proposed as sensitive redox indicators in the micro determination of iron(II), arsenic(III), molybdenum(V), uranium(IV) and hydroquinone with 0.001-0.0005N cerium(IV) sulphate in sulphuric, hydrochloric and acetic acid media. They give sharp colour change from light turquoise blue to pale purple colour at the equivalence point. They have advantages over a few existing redox indicators.

Bacterial sulphate reduction and the development of alkalinity. I. Experiments with synthetic media

Energy Technology Data Exchange (ETDEWEB)

Abd-El-Malek, Y; Rizk, S G

1963-01-01

In liquid cultures of desulphovibrio desulphuricans the effects of the following on sulphate reduction were determined: The type of cation (ca++ or na+) attached to the sulphate ion; the presence of calcium carbonate alone and with sodium chloride; the concentration of sodium sulphate, sodium lactate and sodium chloride; and the initial pH. The titratable alkalinity formed as a result of sulphate reduction was found to be quantitatively related to the sulphate reduced, and apparently unaffected by strain variation or energy source.

Sulphation reactions of oxidic dust particles in waste heat boiler environment. Literature review

Energy Technology Data Exchange (ETDEWEB)

Ranki, T.

1999-09-01

Sulphation of metal oxides has an important role in many industrial processes. In different applications sulphation reactions have different aims and characteristics. In the flash smelting process sulphation of oxidic flue dust is a spontaneous and inevitable phenomena, which takes place in the waste heat boiler (WHB) when cooling down hot dust laden off-gases from sulphide smelters. Oxidic dust particles (size 0 - 50 {mu}m) react with O{sub 2} and SO{sub 2} or SO{sub 3} in a certain temperature range (500 - 800 deg C). Sulphation reactions are highly exothermic releasing large amount of heat, which affects the gas cooling and thermal performance of the boiler. Thermodynamics and kinetics of the system have to be known to improve the process and WHB operation. The rate of sulphation is affected by the prevailing conditions (temperature, gas composition) and particle size and microstructure (porosity, surface area). Some metal oxides (CuO) can react readily with SO{sub 2} and O{sub 2} and act as self-catalysts, but others (NiO) require the presence of an external catalyst to enhance the SO{sub 3} formation and sulphation to proceed. Some oxides (NiO) sulphate directly, some (CuO) may form first intermediate phases (basic sulphates) depending on the reaction conditions. Thus, the reaction mechanisms are very complex. The aim of this report was to search information about the factors affecting the dust sulphation reactions and suggested reaction mechanisms and kinetics. Many investigators have studied sulphation thermodynamics and reaction kinetics and mechanisms of macroscopical metal oxide pieces, but only few articles have been published about sulphation of microscopical particles, like dust. All the found microscale studies dealt with sulphation reactions of calcium oxide, which is not present in the flash smelting process, but used as an SO{sub 2} absorbent in the combustion processes. However, also these investigations may give some hints about the sulphation

Effects of salinity, commercial salts, and water type on cultivation of the cryptophyte microalgae Rhodomonas salina and the calanoid Copepod Acartia tonsa

DEFF Research Database (Denmark)

Jepsen, Per Meyer; Thoisen, Christina V.; Carron-Cabaret, Thibaut

2018-01-01

Marine aquaculture facilities positioned far from the sea need access to seawater (SW); hence, commercial salts are often the chosen solution. In marine hatcheries, most fish larvae require live feed (zooplankton) that are in turn fed with microalgae. The objective of this research was to investi......Marine aquaculture facilities positioned far from the sea need access to seawater (SW); hence, commercial salts are often the chosen solution. In marine hatcheries, most fish larvae require live feed (zooplankton) that are in turn fed with microalgae. The objective of this research...... was to investigate the applicability of commercial salts and clarify the potential effects on the cultivation of the microalga Rhodomonas salina and the copepod Acartia tonsa. Three commercial salts were tested, Red Sea Salt (RS), Red Sea – Coral Pro Salt (CP), and Blue Treasure Salt. R. salina was cultured...

Aerosol-driven increase in Arctic sea ice over the middle of the twentieth century

Science.gov (United States)

Gagné, Marie-Ève; Fyfe, John C.; Gillett, Nathan P.; Polyakov, Igor V.; Flato, Gregory M.

2017-07-01

Updated observational data sets without climatological infilling show that there was an increase in sea ice concentration in the eastern Arctic between 1950 and 1975, contrary to earlier climatology infilled observational data sets that show weak interannual variations during that time period. We here present climate model simulations showing that this observed sea ice concentration increase was primarily a consequence of cooling induced by increasing anthropogenic aerosols and natural forcing. Indeed, sulphur dioxide emissions, which lead to the formation of sulphate aerosols, peaked around 1980 causing a sharp increase in the burden of sulphate between the 1950s and 1970s; but since 1980, the burden has dropped. Our climate model simulations show that the cooling contribution of aerosols offset the warming effect of increasing greenhouse gases over the midtwentieth century resulting in the expansion of the Arctic sea ice cover. These results challenge the perception that Arctic sea ice extent was unperturbed by human influence until the 1970s, suggesting instead that it exhibited earlier forced multidecadal variations, with implications for our understanding of impacts and adaptation in human and natural Arctic systems.

Thermal decomposition of uranyl sulphate hydrate

International Nuclear Information System (INIS)

Sato, T.; Ozawa, F.; Ikoma, S.

1980-01-01

The thermal decomposition of uranyl sulphate hydrate (UO 2 SO 4 .3H 2 O) has been investigated by thermogravimetry, differential thermal analysis, X-ray diffraction and infrared spectrophotometry. As a result, it is concluded that uranyl sulphate hydrate decomposes thermally: UO 2 SO 4 .3H 2 O → UO 2 SO 4 .xH 2 O(2.5 = 2 SO 4 . 2H 2 O → UO 2 SO 4 .H 2 O → UO 2 SO 4 → α-UO 2 SO 4 → β-UO 2 SO 4 → U 3 O 8 . (author)

Thermometric titration of sulphate.

Science.gov (United States)

Williams, M B; Janata, J

1970-06-01

Direct thermometric titration of sulphate with a solution of barium perchlorate is proposed. The stoichiometry of the titration is shown to be critically dependent on the concentration of ethanol in the titration medium. The titration is rapid and suffers from only a few interferences.

Adsorption behavior of radionuclide in water containing sea salts

International Nuclear Information System (INIS)

Kani, Yuko; Kamoshida, Mamoru; Asano, Takashi; Tamata, Shin

2012-01-01

Waste water caused by the Fukushima Dai-ichi Nuclear Reactor accident contains high level radioactive material with impurities of sea water origin, such as chloride, sodium and magnesium. These impurities have the potential to inhibit the adsorption reaction of radioactive cesium and strontium to adsorbents. We have studied adsorption behavior of radioactive cesium and strontium to adsorbents to measure distribution coefficients (Kd) in the condition of different sea water concentrations. For cesium adsorption, the dependence of Kd on the sea water concentration was affected by the adsorption mechanism of adsorbent; the adsorbents which adsorbed cesium by intercalation showed less dependence of Kd on the sea water concentration, while those adsorbed cesium by ion exchange had smaller Kd with increasing the sea water concentration. For strontium adsorption, Kd decreased as the sea water concentration increased for both adsorbents which adsorbed strontium by intercalation and by ion exchange. The inhibition of intercalation and ion exchange reaction of strontium by calcium ion, that exists high concentration in sea water (400 ppm) and similar hydrated ionic radius with strontium, will cause the decrease of Kd for strontium in the sea water with higher concentration. (author)

Magnesium sulphate for fetal neuroprotection

DEFF Research Database (Denmark)

Bickford, Celeste D; Magee, Laura A; Mitton, Craig

2013-01-01

of cerebral palsy (CP) averted and quality-adjusted life years (QALYs). RESULTS: From a health system and a societal perspective, respectively, a savings of $2,242 and $112,602 is obtained for each QALY gained and a savings of $30,942 and $1,554,198 is obtained for each case of CP averted when magnesium......BACKGROUND: The aim of this study was to assess the cost-effectiveness of administering magnesium sulphate to patients in whom preterm birth at ... sensitivity analyses were used to compare the administration of magnesium sulphate with the alternative of no treatment. Two separate cost perspectives were utilized in this series of analyses: a health system and a societal perspective. In addition, two separate measures of effectiveness were utilized: cases...

Holocene sea-level changes in the Falkland Islands

Science.gov (United States)

Newton, Tom; Gehrels, Roland; Daley, Tim; Long, Antony; Bentley, Mike

2014-05-01

In many locations in the southern hemisphere, relative sea level (RSL) reached its maximum position during the middle Holocene. This highstand is used by models of glacial isostatic adjustment (GIA) to constrain the melt histories of the large ice sheets, particularly Antarctica. In this paper we present the first Holocene sea-level record from the Falkland Islands (Islas Malvinas), an archipelago located on the Patagonian continental shelf about 500 km east of mainland South America at a latitude of ca. 52 degrees. Unlike coastal locations in southernmost South America, Holocene sea-level data from the Falklands are not influenced by tectonics, local ice loading effects and large tidal ranges such that GIA and ice-ocean mass flux are the dominant drivers of RSL change. Our study site is a salt marsh located in Swan Inlet in East Falkland, around 50 km southwest of Stanley. This is the largest and best developed salt marsh in the Falkland Islands. Cores were collected in 2005 and 2013. Lithostratigraphic analyses were complemented by analyses of foraminifera, testate amoebae and diatoms to infer palaeoenvironments. The bedrock, a Permian black shale, is overlain by grey-brown organic salt-marsh clay, up to 90 cm thick, which, in a landward direction, is replaced by freshwater organic sediments. Overlying these units are medium-coarse sands with occasional pebbles, up to 115 cm thick, containing tidal flat foraminifera. The sandy unit is erosively overlain by a grey-brown organic salt-marsh peat which extends up to the present surface. Further away from the sea this unit is predominantly of freshwater origin. Based on 13 radiocarbon dates we infer that prior to ~9.5 ka sea level was several metres below present. Under rising sea levels a salt marsh developed which was suddenly drowned around 8.4 ka, synchronous with a sea-level jump known from northern hemisphere locations. Following the drowning, RSL rose to its maximum position around 7 ka, less than 0.5 m above

Sulphate, more than a nutrient, protects the microalga Chlamydomonas moewusii from cadmium toxicity

Energy Technology Data Exchange (ETDEWEB)

Mera, Roi; Torres, Enrique, E-mail: torres@udc.es; Abalde, Julio

2014-03-01

Highlights: • Sulphate effect on cadmium toxicity in the microalga Chlamydomonas moewusii Gerloff. • Cadmium increases the sulphur requirements in Chlamydomonas moewusii. • Kinetic coefficients for sulphate utilization and cadmium effect on them. • Sulphate and cadmium influence on the biosynthesis of low-molecular mass thiols. • Cadmium toxicity reduction by sulphate due to higher biosynthesis of thiols. - Abstract: Sulphur is an essential macroelement that plays important roles in living organisms. The thiol rich sulphur compounds, such as cysteine, γ-Glu–Cys, glutathione and phytochelatins participate in the tolerance mechanisms against cadmium toxicity. Plants, algae, yeasts and most prokaryotes cover their demand for reduced sulphur by reduction of inorganic sulphate. The aim of this study was to investigate, using a bifactorial experimental design, the effect of different sulphate concentrations in the nutrient solution on cadmium toxicity in the freshwater microalga Chlamydomonas moewusii. Cell growth, kinetic parameters of sulphate utilization and intracellular concentrations of low-molecular mass thiol compounds were determined. A mathematical model to describe the growth of this microalga based on the effects of sulphate and cadmium was obtained. An ANOVA revealed an interaction between them, 16% of the effect sizes was explained by this interaction. A higher amount of sulphate in the culture medium allowed a higher cadmium tolerance due to an increase in the thiol compound biosynthesis. The amount of low-molecular mass thiol compounds, mainly phytochelatins, synthesized by this microalga was significantly dependent on the sulphate and cadmium concentrations; the higher phytochelatin content was obtained in cultures with 4 mg Cd/L and 1 mM sulphate. The maximum EC{sub 50} value (based on nominal cadmium concentration) reached for this microalga was 4.46 ± 0.42 mg Cd/L when the sulphate concentration added to the culture medium was also 1 m

Relationship between sulphate and sulphur dioxide in the air

Energy Technology Data Exchange (ETDEWEB)

Fugas, M; Gentilizza, M

1978-01-01

The relationship between the sulphate in suspended particulates and sulphur dioxide in the air was studied in various urban and industrial areas. The relationship is best described by the equation y = ax/sup b/, where y is the percentage of the sulphate S in the total S (sulphate and sulphur dioxide) and x is the concentration of the total S in the air. The regression coefficients a and b seem to be characteristics of the area. In urban areas studied so far a was between 316 and 378 and b between -0.74 and -0.83. In industrial areas polluted by dust which contains elevated concentrations of metals a was between 91 and 107 and b between -0.35 and -0.49. In the area polluted by cement dust there was practically no correlation between the sulphate S (%) and the total S, but a relatively high correlation between absolute amounts of the sulphate S and the total S. The relations indicate that the limitation of SO/sub 2/ conversion is influenced by aerosol composition. Aerosols containing certain metals may promote the conversion by a catalytic effect while alkaline substances by increasing the pH. Whether this can only happen in the plume or in the air as well remains to be clarified.

A history of salt.

Science.gov (United States)

Cirillo, M; Capasso, G; Di Leo, V A; De Santo, N G

1994-01-01

The medical history of salt begins in ancient times and is closely related to different aspects of human history. Salt may be extracted from sea water, mineral deposits, surface encrustations, saline lakes and brine springs. In many inland areas, wood was used as a fuel source for evaporation of brine and this practice led to major deafforestation in central Europe. Salt played a central role in the economies of many regions, and is often reflected in place names. Salt was also used as a basis for population censuses and taxation, and salt monopolies were practised in many states. Salt was sometimes implicated in the outbreak of conflict, e.g. the French Revolution and the Indian War of Independence. Salt has also been invested with many cultural and religious meanings, from the ancient Egyptians to the Middle Ages. Man's innate appetite for salt may be related to his evolution from predominantly vegetarian anthropoids, and it is noteworthy that those people who live mainly on protein and milk or who drink salty water do not generally salt their food, whereas those who live mainly on vegetables, rice and cereals use much more salt. Medicinal use tended to emphasize the positive aspects of salt, e.g. prevention of putrefaction, reduction of tissue swelling, treatment of diarrhea. Evidence was also available to ancient peoples of its relationship to fertility, particularly in domestic animals. The history of salt thus represents a unique example for studying the impact of a widely used dietary substance on different important aspects of man's life, including medical philosophy.

Under-ice eddy covariance flux measurements of heat, salt, momentum, and dissolved oxygen in an artificial sea ice pool

DEFF Research Database (Denmark)

Else, B. G T; Rysgaard, S.; Attard, K.

2015-01-01

as one possible cause of the high fluxes. Momentum fluxes showed interesting correlations with ice growth and melt but were generally higher than expected. We concluded that with the exception of the conductivity sensor, the eddy covariance system worked well, and that useful information about turbulent......Turbulent exchanges under sea ice play a controlling role in ice mass balance, ice drift, biogeochemistry, and mixed layer modification. In this study, we examined the potential to measure under-ice turbulent exchanges of heat, salt, momentum, and dissolved oxygen using eddy covariance...... in an experimental sea ice facility. Over a 15-day period in January 2013, an underwater eddy covariance system was deployed in a large (500 m3) inground concrete pool, which was filled with artificial seawater and exposed to the ambient (−5 to −30 °C) atmosphere. Turbulent exchanges were measured continuously...

Moisture distribution in the stone portal of a church: how it influences the salt accumulation in porous limestone

Science.gov (United States)

Török, Ákos; Galambos, Éva

2017-04-01

Mathias Church of Budapest (Hungary) is an emblematic stone monument that represents various phases of constructions from Medieval period to the early 20th century. The church is found at the elevated Castle Hill and forms a landmark at the UNESCO World Heritage Site of Budapest. Its main construction material is porous Miocene limestone. Besides porous limestone travertine was also extensively used. The current study focuses on the Medieval Gate of the church which encompasses richly decorated porous limestone ornaments. The gate is now sheltered and form an interior portal of the church. It shows various forms of stone decay. The most striking one is efflorescence of salts. This feature has become more intense in the past years leading to flaking and granular disintegration of the limestone, causing damage to the monument. This study focuses on the detection of moisture content within the stone structure and its role in the salt accumulation. To obtain this goal in situ moisture measurements were made along vertical profiles by a portable moisture detector (Gann-Hydromette). It allowed outlining the moisture distribution within the studied structure. The moisture measurement was combined with sampling of salt efflorescence and porous limestone of the gate, itself. The samples were tested by optical microscopy. Conductivity, salt content and main elements were also detected from solutions. Mineralogical composition was recorded by XRD and Thermogravimetric analyses. Magnesium-sulphates were found to be the main salts responsible for damages. Besides sulphates chlorides were also detected. Gypsum was also found in the weathering crusts of the previously exposed limestone surfaces. It accumulated in black crusts but was also detected in white efflorescence and below the stone surface. The salt distribution clearly correlates with the moisture content. The financial support of NKFI Fund (ref. no. K 116532) is appreciated.

Cysteic acid and taurine synthesis from sulphate in the chick embryo

International Nuclear Information System (INIS)

Chapeville, F.

1960-01-01

The formation of taurine from sulphate was studied in the chick embryo using the radioisotopes of: sulphur, carbon and hydrogen. The following reactions occur: 1) reduction of sulphate to sulphite; 2) fixation of the sulphite on a carbon chain with an amino group, resulting from desulphydration of L-cysteine, which leads to the formation of L-cysteic acid; 3) decarboxylation of L-cysteic acid. Reaction (1) takes place only in the endo-dermal cells of the yolk sac; reaction (2) in these same cells and in the yolk; reaction (3) is general, localized in the yolk sac, in the yolk as well as in the tissues of the embryo itself. The enzyme which catalyses reaction (2) has been purified; the coenzyme is pyridoxal phosphate. The desulphydration of cysteine by this enzyme is a reversible reaction. In non-physiological conditions of concentration and temperature, pyridoxal phosphate catalyses in the presence of metallic ions, the desulphydration of cysteine and the formation of cysteic acid from sulphite. (author) [fr

Feasibility of lead removal from industrial effluents by sulphate reducing bacteria

International Nuclear Information System (INIS)

Nunez, L. A.; Diez, M.; Rodriguez, F. J.

2009-01-01

Battery manufacturing wastewater contains high concentration of sulphate and lead at low pH values. Biogical treatment by anaerobic reduction of sulphate to sulphite, with organic matter as electron donor, increases alkalinity and allow precipitating lead as sulphide. the type of organic matter, COD/SO 4 ratio and lead concentration over sulphate reduction rate are investigated in this work. (Author)

Differential responses of freshwater wetland soils to sulphate pollution

NARCIS (Netherlands)

Lamers, L.P.M.; Dolle, ten G.E.; Berg, van den S.T.G.; Delft, van S.P.J.; Roelofs, J.G.M.

2001-01-01

Sulphate (SO42-) reduction rates are generally low in freshwater wetlands and are regulated by the scarce availability of the ion. Increased concentrations of this electron acceptor due to sulphur (S) pollution of groundwater and surface water may, however, lead to high sulphate reduction rates now

Climatology of salt transitions and implications for stone weathering

International Nuclear Information System (INIS)

Grossi, C.M.; Brimblecombe, P.; Menendez, B.; Benavente, D.; Harris, I.; Deque, M.

2011-01-01

This work introduces the notion of salt climatology. It shows how climate affects salt thermodynamic and the potential to relate long-term salt damage to climate types. It mainly focuses on specific sites in Western Europe, which include some cities in France and Peninsular Spain. Salt damage was parameterised using the number of dissolution-crystallisation events for unhydrated (sodium chloride) and hydrated (sodium sulphate) systems. These phase transitions have been calculated using daily temperature and relative humidity from observation meteorological data and Climate Change models' output (HadCM3 and ARPEGE). Comparing the number of transitions with meteorological seasonal data allowed us to develop techniques to estimate the frequency of salt transitions based on the local climatology. Results show that it is possible to associate the Koeppen-Geiger climate types with potential salt weathering. Temperate fully humid climates seem to offer the highest potential for salt damage and possible higher number of transitions in summer. Climates with dry summers tend to show a lesser frequency of transitions in summer. The analysis of temperature, precipitation and relative output from Climate Change models suggests changes in the Koeppen-Geiger climate types and changes in the patterns of salt damage. For instance, West Europe areas with a fully humid climate may change to a more Mediterranean like or dry climates, and consequently the seasonality of different salt transitions. The accuracy and reliability of the projections might be improved by simultaneously running multiple climate models (ensembles). - Research highlights: → We introduce the notion of salt climatology for heritage conservation. → Climate affects salt thermodynamics on building materials. → We associate Koeppen-Geiger climate types with potential salt weathering. → We offer future projections of salt damage in Western Europe due to climate change. → Humid climate areas may change to

Climatology of salt transitions and implications for stone weathering

Energy Technology Data Exchange (ETDEWEB)

Grossi, C.M., E-mail: c.grossi-sampedro@uea.ac.uk [School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ (United Kingdom); Brimblecombe, P. [School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ (United Kingdom); Menendez, B. [Geosciences et Environnement Cergy, Universite de Cergy-Pontoise 95031 Cergy-Pontoise cedex (France); Benavente, D. [Lab. Petrologia Aplicada, Unidad Asociada UA-CSIC, Dpto. Ciencias de la Tierra y del Medio Ambiente, Universidad de Alicante, Alicante 03080 (Spain); Harris, I. [Climatic Research Unit, School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ (United Kingdom); Deque, M. [Meteo-France/CNRM, CNRS/GAME, 42 Avenue Coriolis, F-31057 Toulouse, Cedex 01 (France)

2011-06-01

This work introduces the notion of salt climatology. It shows how climate affects salt thermodynamic and the potential to relate long-term salt damage to climate types. It mainly focuses on specific sites in Western Europe, which include some cities in France and Peninsular Spain. Salt damage was parameterised using the number of dissolution-crystallisation events for unhydrated (sodium chloride) and hydrated (sodium sulphate) systems. These phase transitions have been calculated using daily temperature and relative humidity from observation meteorological data and Climate Change models' output (HadCM3 and ARPEGE). Comparing the number of transitions with meteorological seasonal data allowed us to develop techniques to estimate the frequency of salt transitions based on the local climatology. Results show that it is possible to associate the Koeppen-Geiger climate types with potential salt weathering. Temperate fully humid climates seem to offer the highest potential for salt damage and possible higher number of transitions in summer. Climates with dry summers tend to show a lesser frequency of transitions in summer. The analysis of temperature, precipitation and relative output from Climate Change models suggests changes in the Koeppen-Geiger climate types and changes in the patterns of salt damage. For instance, West Europe areas with a fully humid climate may change to a more Mediterranean like or dry climates, and consequently the seasonality of different salt transitions. The accuracy and reliability of the projections might be improved by simultaneously running multiple climate models (ensembles). - Research highlights: {yields} We introduce the notion of salt climatology for heritage conservation. {yields} Climate affects salt thermodynamics on building materials. {yields} We associate Koeppen-Geiger climate types with potential salt weathering. {yields} We offer future projections of salt damage in Western Europe due to climate change. {yields} Humid

The effect of magnesium on partial sulphate removal from mine water as gypsum.

Science.gov (United States)

Tolonen, Emma-Tuulia; Rämö, Jaakko; Lassi, Ulla

2015-08-15

The aim of this research was to investigate the effect of magnesium on the removal efficiency of sulphate as gypsum from mine water. The precipitation conditions were simulated with MINEQL + software and the simulation results were compared with the results from laboratory jar test experiments. Both the simulation and the laboratory results showed that magnesium in the mine water was maintaining sulphate in a soluble form as magnesium sulphate (MgSO4) at pH 9.6. Thus magnesium was preventing the removal of sulphate as gypsum (CaSO4·2H2O). However, change in the lime precipitation pH from 9.6 to 12.5 resulted in magnesium hydroxide (Mg(OH)2) precipitation and improved sulphate removal. Additionally, magnesium hydroxide could act as seed crystals for gypsum precipitation or co-precipitate sulphate further enhancing the removal of sulphate from mine water. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sulphated glycosaminoglycans and proteoglycans in the developing vertebral column of juvenile Atlantic salmon (Salmo salar)

OpenAIRE

Hannesson, Kirsten O.; Ytteborg, Elisabeth; Takle, Harald; Enersen, Grethe; B?verfjord, Grete; Pedersen, Mona E.

2015-01-01

In the present study, the distribution of sulphated glycosaminoglycans (GAGs) in the developing vertebral column of Atlantic salmon (Salmo salar) at 700, 900, 1100 and 1400?d? was examined by light microscopy. The mineralization pattern was outlined by Alizarin red S and soft structures by Alcian blue. The temporal and spatial distribution patterns of different types of GAGs: chondroitin-4-sulphate/dermatan sulphate, chondroitin-6-sulphate, chondroitin-0-sulphate and keratan sulphate were add...

Microwave assisted synthesis of nano sized sulphate doped hydroxyapatite

International Nuclear Information System (INIS)

Alshemary, Ammar Z.; Goh, Yi-Fan; Akram, Muhammad; Razali, Ili Rabihah; Abdul Kadir, Mohammed Rafiq; Hussain, Rafaqat

2013-01-01

Highlights: ► Phase pure nano-sized sulphur doped hydroxyapatite has been synthesized. ► TEM analysis confirmed formation of needle shaped structure. ► Lattice parameters and cell volume increased with increase in sulphate doping. ► Crystallite size decreased as sulphate content inside the structure increased. ► Degree of crystallinity decreased with increase in sulphate substitution. - Abstract: Inorganic sulphate is required by all mammalian cells to function properly, it is the fourth most abundant anion in the human plasma. Sulphate ions are the major source of sulphur which is considered an important element for sustenance of life as it is present in the essential amino and is required by cells to function properly. In this study we have successfully substituted sulphate ions (SO 4 2− ) into hydroxyapatite (Ca 10 (PO 4 ) 6−x (SO 4 ) x (OH) 2−x ) lattice via ion exchange process with phosphate group. Concentration of SO 4 2− ions was varied between X = 0.05–0.5, using (Ca (NO 3 ) 2 ·4H 2 O), ((NH 4 ) 2 HPO 4 ) and (Na 2 SO 4 ) as starting materials. X-ray diffraction (XRD), Fourier transform IR spectroscopy (FTIR), showed that the substitution of SO 4 2− ions into the lattice resulted in peak broadening and reduced peak height due to the amorphous nature and reduced crystallinity of the resulting HA powder. Transmission electron microscopy (TEM) and field emission electron microscopy (FESEM) analysis confirmed the formation of needle shaped particles of 41 nm size with homogenous and uniform distribution of element within the HA structure

A Nucleus-localized Long Non-Coding RNA Enhances Drought and Salt Stress Tolerance

KAUST Repository

Qin, Tao; Zhao, Huayan; Cui, Peng; Albesher, Nour H.; Xiong, Liming

2017-01-01

stress. DRIR was expressed at a low level under non-stress conditions but can be significantly activated by drought and salt stress as well as by abscisic acid (ABA) treatment. We identified a T-DNA insertion mutant, drirD, which had higher expression

Silicon-mediated changes in polyamines participate in silicon-induced salt tolerance in Sorghum bicolor L.

Science.gov (United States)

Yin, Lina; Wang, Shiwen; Tanaka, Kiyoshi; Fujihara, Shinsuke; Itai, Akihiro; Den, Xiping; Zhang, Suiqi

2016-02-01

Silicon (Si) is generally considered a beneficial element for the growth of higher plants, especially under stress conditions, but the mechanisms remain unclear. Here, we tested the hypothesis that Si improves salt tolerance through mediating important metabolism processes rather than acting as a mere mechanical barrier. Seedlings of sorghum (Sorghum bicolor L.) growing in hydroponic culture were treated with NaCl (100 mm) combined with or without Si (0.83 mm). The result showed that supplemental Si enhanced sorghum salt tolerance by decreasing Na(+) accumulation. Simultaneously, polyamine (PA) levels were increased and ethylene precursor (1-aminocyclopropane-1-carboxylic acid: ACC) concentrations were decreased. Several key PA synthesis genes were up-regulated by Si under salt stress. To further confirm the role of PA in Si-mediated salt tolerance, seedlings were exposed to spermidine (Spd) or a PA synthesis inhibitor (dicyclohexylammonium sulphate, DCHA) combined with salt and Si. Exogenous Spd showed similar effects as Si under salt stress whereas exogenous DCHA eliminated Si-enhanced salt tolerance and the beneficial effect of Si in decreasing Na(+) accumulation. These results indicate that PAs and ACC are involved in Si-induced salt tolerance in sorghum and provide evidence that Si plays an active role in mediating salt tolerance. © 2015 John Wiley & Sons Ltd.

Study of Factors Influencing Oxygen-18 Isotopic Contents of Dissolved Sulphate in the Shallow Groundwater In Karawang Area

International Nuclear Information System (INIS)

Ristin Pujiindiyati, E.; Bungkus Pratikno

2010-01-01

The study was conducted to investigate the factors influencing oxygen-18 isotopic contents of dissolved sulphate in shallow groundwater from Karawang area. The δ 18 O is a relative abundance of O-18 compared to O-16 in CO 2 gas. CO 2 gas was released from the equilibrium between water samples and CO 2 gas, and from the reduction of sulphate samples with graphite. From this investigation, the δ 18 O (H 2 O) values were in the range of -3.21 0 / 00 to 6.25 0 / 00 whereas the δ 18 O (SO 4 2- ) values were 9.64 0 / 00 to 20.72 0 / 00 . The wide variation of δ 18 O (SO 4 2- ) values might be result due to inhomogeneity of sulphate sources in groundwater where the groundwater sulphates were generally derived from the dissolution of marine evaporites rocks. The groundwaters and Citarum River near waters to Johar site showed lowering of δ 18 O (SO 4 2- ) values. It might be related to the present of the traditional market in this location. The lowering of these values might be due to the increase of the sulphate reduction process caused by anaerobic bacteria growth in organic garbage deposition. Plotting between δ 18 O (SO 4 2- ) and δ 18 O (H 2 O) exhibited that the oxygen contribution from H 2 O to form sulphate was less than 25%. This indicated that the shallow groundwater in Karawang is located in a non-saturated zone and had a biotic condition. (author)

Sulphate removal from uraniferous liquors

International Nuclear Information System (INIS)

Berger, B.

1983-01-01

A process for the recovery of uranium from liquor resulting from the attack of sulphur containing uraniferous ores by an alkaline solution of sodium carbonate and/or sodium bicarbonate is claimed. An ion exchange resin is used to separate the uranium from the solution of sodium carbonate and/or bicarbonate and sodium sulphate. The ion exchange resin is then eluted with a solution of ammonium carbonate and/or bicarbonate to provide an eluate containing ammonium uranyl tricarbonate, ammonium carbonate and/or bicarbonate and ammonium sulphate. The eluate is heated to boiling to convert the ammonium uranyl tricarbonate to ammonium uranate and/or diuranate. Ammonia, carbon dioxide and water vapor are released. The precipitated ammonium uranate and/or diuranate is separated from the remaining liquor and calcined to give uranium trioxide

Bacillus isabeliae sp. nov., a halophilic bacterium isolated from a sea salt evaporation pond.

Science.gov (United States)

Albuquerque, Luciana; Tiago, Igor; Taborda, Marco; Nobre, M Fernanda; Veríssimo, António; da Costa, Milton S

2008-01-01

A low-G+C, Gram-positive isolate, designated strain CVS-8(T), was isolated from a sea salt evaporation pond on the Island of Sal in the Cape Verde Archipelago. This organism was found to be a catalase- and oxidase-positive, non-motile, spore-forming, aerobic, curved rod-shaped organism with an optimum growth temperature of about 35-37 degrees C and an optimum pH between 7.5 and 8.0. Optimal growth occurred in media containing 4-6% (w/v) NaCl and no growth occurred in medium without NaCl. The cell-wall peptidoglycan was of the A1gamma type with meso-diaminopimelic acid, the major respiratory quinone was MK-7, the major fatty acids were iso-15:0, 16:0, anteiso-15:0 and iso-16:0 and the major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and an unidentified aminoglycophospholipid. The G+C content of the DNA was 37.9 mol%. Phylogenetic analysis of the 16S rRNA gene sequence indicated that strain CVS-8(T) represented a novel species of the genus Bacillus, the highest levels of sequence similarity (mean pairwise similarity values of approximately 97.5 %) being found with respect to the type strains of Bacillus shackletonii and Bacillus acidicola. On the basis of the phylogenetic, physiological and biochemical data, strain CVS-8(T) represents a novel species of the genus Bacillus, for which the name Bacillus isabeliae sp. nov. is proposed. The type strain is CVS-8(T) (=LMG 22838(T)=CIP 108578(T)).

Serum and urinary oestrone sulphate in pregnancy and delivery measured by a direct radioimmunoassay

International Nuclear Information System (INIS)

Honjo, Hideo; Kitawaki, Jo; Itoh, Masafumi; Yasuda, Jinsuke; Yamamoto, Takara; Yamamoto, Takao; Okada, Hiroji; Ohkubo, Tadashi; Nambara, Toshio

1986-01-01

Serum and urinary levels of oestrone sulphate in pregnancy and delivery were measured by a direct radioimmunoassay without hydrolysis. the serum and urinary oestrone sulphate increased as pregnancy progressed. the mean level of serum oestrone sulphate increased to the highest peak of 494 pmol/ml at the 35th gestational week and then decreased. The mean level of urinary oestrone sulphate increased to the highest peak of 1.28 μmol/l at the 34th gestational week and the decreased. At vaginal deliveries, the mean level of maternal peripheral serum oestrone sulphate increased hourly at as high a level as 979 pmol/ml. The mean serum level of oestrone sulphate was 204 pmol/ml in the umbilical artery and 145 pmol/ml in the umbilical vein. At Caesarean section, on the other hand, the maternal peripheral serum level of oestrone sulphate averaged 362 pmol/ml. The mean serum levels of oestrone sulphate wre 90.7 pmol/ml and 171 pmol/ml in the umbilical artery and umbilical vein, respectively. These results suggest a maternal origin of oestrone sulphate in pregnancy, with fluctuations in the levels being of interest in relation to labour pain. (author)

Synthesis of Poly(para-phenylene terephthalamide and Preparation of Short Fibers: Effect of Sodium Sulphate on the Fibers

Directory of Open Access Journals (Sweden)

mohammad ali Semsarzadeh

2012-12-01

Full Text Available Kevlar is one of the fbers which is used in heavy industrial productions such as, shipping, military and weaving for reinforcement of composites. Initial polymer of Kevlar or poly(para-phenylene terephthalamide is an oriented liquid crystal polymer. Existence of aromatic group in the main chain leads to formation of rigid-rod molecules in the polymer, high strength and high modulus in it is fbers. Impurities in the polymer lead to decrease in fbers performance. In this research, poly(para - phenylene terephthalamide was synthesized from polycondensation of phenylene diamine and terephthaloyl dichloride in n-methyl pyrrolidone and calcium chloride (NMP-CaCl2 solution. Fourier transform infrared spectroscopy (FTIR and X-ray diffraction (XRD tests were carried out to characterize chemical bonds and crystalline plates of the polymer, respectively. Concentrated sulfuric acid is a solvent of poly(phenylene terephthalate therefore, this polymer was dissolved in concentreated sulfuric acid (96% and  the polymer solution was  injected  into  the cylindrical tank contain water. Sulfuric acid was transferred into water and the polymer was solidifed. After solidifcation,  tensile  force of vortex  led  to orientation of  rigid-rod polymer molecules  in direction of water rotation and  long fbers were formed from the polymer. The fbers were broken to short fbers by the same force of vortex. The short fbers were dried. SEM  images showed  the regular particles on  the surface of fbers. Results of FTIR and XRD proved that the regular particles are sodium sulphate salt. The effect of sodium sulphate salt as an impurity on the short fbers was studied.

Multiple functions of a multi-component mating pheromone in sea lamprey Petromyzon marinus

Science.gov (United States)

Johnson, N.S.; Yun, S.-S.; Buchinger, T.J.; Li, W.

2012-01-01

The role of the C24 sulphate in the mating pheromone component, 7α,12α,24-trihydroxy-5α-cholan-3-one 24-sulphate (3kPZS), to specifically induce upstream movement in ovulated female sea lampreys Petromyzon marinus was investigated. 7α,12α-dihydroxy-5α-cholan-3-one 24-oic acid (3kACA), a structurally similar bile acid released by spermiated males, but lacking the C24 sulphate ester, was tested in bioassays at concentrations between 10−11 and 10−14 molar (M). 3kACA did not induce upstream movement in females or additional reproductive behaviours. In contrast, spermiated male washings induced upstream movement, prolonged retention on a nest and induced an array of nesting behaviours. Differential extraction and elution by solid-phase extraction resins showed that components other than 3kPZS + 3kACA are necessary to retain females on nests and induce nest cleaning behaviours. All pheromone components, including components in addition to 3kPZS + 3kACA that retain females and induce nest cleaning behaviours were released from the anterior region of the males, as had been reported for 3kPZS. It is concluded that the sea lamprey male mating pheromone has multiple functions and is composed of multiple components.

Effects of livestock species and stocking density on accretion rates in grazed salt marshes

Science.gov (United States)

Nolte, Stefanie; Esselink, Peter; Bakker, Jan P.; Smit, Christian

2015-01-01

Coastal ecosystems, such as salt marshes, are threatened by accelerated sea-level rise (SLR). Salt marshes deliver valuable ecosystem services such as coastal protection and the provision of habitat for a unique flora and fauna. Whether salt marshes in the Wadden Sea area are able to survive accelerated SLR depends on sufficient deposition of sediments which add to vertical marsh accretion. Accretion rate is influenced by a number of factors, and livestock grazing was recently included. Livestock grazing is assumed to reduce accretion rates in two ways: (a) directly by increasing soil compaction through trampling, and (b) indirectly by affecting the vegetation structure, which may lower the sediment deposition. For four years, we studied the impact of two livestock species (horse and cattle) at two stocking densities (0.5 and 1.0 animal ha-1) on accretion in a large-scale grazing experiment using sedimentation plates. We found lower cumulative accretion rates in high stocking densities, probably because more animals cause more compaction and create a lower canopy. Furthermore, a trend towards lower accretion rates in horse-compared to cattle-grazed treatments was found, most likely because (1) horses are more active and thus cause more compaction, and (2) herbage intake by horses is higher than by cattle, which causes a higher biomass removal and shorter canopy. During summer periods, negative accretion rates were found. When the grazing and non-grazing seasons were separated, the impact of grazing differed among years. In summer, we only found an effect of different treatments if soil moisture (precipitation) was relatively low. In winter, a sufficiently high inundation frequency was necessary to create differences between grazing treatments. We conclude that stocking densities, and to a certain extent also livestock species, affect accretion rates in salt marshes. Both stocking densities and livestock species should thus be taken into account in management

Platyamoeba pseudovannellida n. sp., a naked amoeba with wide salt tolerance isolated from the Salton Sea, California.

Science.gov (United States)

Hauer, G; Rogerson, A; Anderson, O R

2001-01-01

A new species of naked amoeba, Platyamoeba pseudovannellida n.sp., is described on the basis of light microscopic and fine structural features. The amoeba was isolated from the Salton Sea, California, from water at a salinity of ca. 44%. Locomotive amoebae occasionally had a spatulate outline and floating cells had radiating pseudopodia, sometimes with pointed tips. Both these features are reminiscent of the genus Vannella. However, the surface coat (glycocalyx) as revealed by TEM indicates that this is a species of Platyamoeba. Although salinity was not used as a diagnostic feature, this species was found to have remarkable tolerance to fluctuating salinity levels, even when changes were rapid. Amoebae survived over the range 0 per thousand to 150 per thousand salt and grew within the range 0 per thousand to 138 per thousand salt. The generation time of cells averaged 29 h and was not markedly affected by salt concentration. This is longer than expected for an amoeba of this size and suggests a high energetic cost of coping with salinity changes. The morphology of cells changed with increasing salinity: at 0 per thousand cells were flattened and active and at the other extreme (138 per thousand) amoebae were wrinkled and domed and cell movement was very slow. At the ultrastructural level, the cytoplasm of cells grown at high salinity (98 per thousand was considerably denser than that of cells reared at 0 per thousand.

The hypobranchial mucin of the whelk Buccinum undatum L. The polysaccharide sulphate component.

Science.gov (United States)

Hunt, S; Jevons, F R

1966-02-01

1. A polysaccharide sulphate has been isolated from the hypobranchial mucin of the whelk Buccinum undatum. 2. The molecular weight of this polysaccharide, which is a glucan carrying one ester sulphate group per monosaccharide residue, is 1.7x10(5). 3. Some investigations bearing on the location of the ester sulphate groups are reported. 4. The viscosity of the whole mucin has been shown to depend mainly on the glucan sulphate.

Microwave assisted synthesis of nano sized sulphate doped hydroxyapatite

Energy Technology Data Exchange (ETDEWEB)

Alshemary, Ammar Z.; Goh, Yi-Fan; Akram, Muhammad; Razali, Ili Rabihah [Department of Chemistry, Faculty of Science, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor Darul Ta’zim (Malaysia); Abdul Kadir, Mohammed Rafiq [Medical Implant Technology Group, Faculty of Biomedical Engineering and Health Science, Universiti Teknologi Malaysia,81310 UTM Skudai, Johor Darul Ta’zim (Malaysia); Hussain, Rafaqat, E-mail: rafaqat@kimia.fs.utm.my [Ibnu Sina Institute for Fundamental Science Studies, Universiti Teknologi Malaysia, 81310 UTM Skudai, Johor DarulTa’zim (Malaysia)

2013-06-01

Highlights: ► Phase pure nano-sized sulphur doped hydroxyapatite has been synthesized. ► TEM analysis confirmed formation of needle shaped structure. ► Lattice parameters and cell volume increased with increase in sulphate doping. ► Crystallite size decreased as sulphate content inside the structure increased. ► Degree of crystallinity decreased with increase in sulphate substitution. - Abstract: Inorganic sulphate is required by all mammalian cells to function properly, it is the fourth most abundant anion in the human plasma. Sulphate ions are the major source of sulphur which is considered an important element for sustenance of life as it is present in the essential amino and is required by cells to function properly. In this study we have successfully substituted sulphate ions (SO{sub 4}{sup 2−}) into hydroxyapatite (Ca{sub 10}(PO{sub 4}){sub 6−x}(SO{sub 4}){sub x}(OH){sub 2−x}) lattice via ion exchange process with phosphate group. Concentration of SO{sub 4}{sup 2−} ions was varied between X = 0.05–0.5, using (Ca (NO{sub 3}){sub 2}·4H{sub 2}O), ((NH{sub 4}){sub 2}HPO{sub 4}) and (Na{sub 2}SO{sub 4}) as starting materials. X-ray diffraction (XRD), Fourier transform IR spectroscopy (FTIR), showed that the substitution of SO{sub 4}{sup 2−} ions into the lattice resulted in peak broadening and reduced peak height due to the amorphous nature and reduced crystallinity of the resulting HA powder. Transmission electron microscopy (TEM) and field emission electron microscopy (FESEM) analysis confirmed the formation of needle shaped particles of 41 nm size with homogenous and uniform distribution of element within the HA structure.

Geologic disposal of nuclear wastes: salt's lead is challenged

International Nuclear Information System (INIS)

Kerr, R.A.

1979-01-01

The types of radioactive waste disposal sites available are outlined. The use of salt deposits and their advantages are discussed. The reasons for the selection of the present site for the Waste Isolation Pilot Plant are presented. The possibilities of using salt domes along the Gulf Coast and not-salt rocks as nuclear waste repositories are also discussed. The sea bed characteristics are described and advantages of this type of site selection are presented

Characteristics and antioxidant of Ulva intestinalis sulphated polysaccharides extracted with different solvents.

Science.gov (United States)

Peasura, Napassorn; Laohakunjit, Natta; Kerdchoechuen, Orapin; Wanlapa, Sorada

2015-11-01

Ulva intestinalis, a tubular green seaweed, is a rich source of nutrient, especially sulphated polysaccharides. Sulphated polysaccharides from U. intestinalis were extracted with distilled water, 0.1N HCl, and 0.1N NaOH at 80°C for 1, 3, 6, 12, and 24h to study the effect of the extraction solvent and time on their chemical composition and antioxidant activity. Different types of solvents and extraction time had a significant influence on the chemical characteristics and antioxidant activity (pMonosaccharide composition and FT-IR spectra analyses revealed that sulphated polysaccharides from all solvent extractions have a typical sugar backbone (glucose, rhamnose, and sulphate attached at C-2 or C-3 of rhamnose). Sulphated polysaccharides extracted with acid exhibited greater antioxidant activity than did those extracted with distilled water and alkali. The results indicated that solvent extraction could be an efficacious method for enhancing antioxidant activity by distinct molecular weight and chemical characteristic of sulphated polysaccharides. Copyright © 2015 Elsevier B.V. All rights reserved.

Quantitation and identification of methanogens and sulphate reducers in Olkiluoto groundwater

International Nuclear Information System (INIS)

Bomberg, M.; Nyyssoenen, M.; Itaevaara, M.

2010-08-01

The GEOFUNC Project focuses on the microbiology connected to safety and risk assessment of the final disposal of high radioactive nuclear waste. Methanogenic archaea and sulphate reducing bacteria are significant groups of microorganisms in anaerobic environments, and are of crucial concern for the safe long term storage of nuclear waste in deep bedrock. The sulphate reducing bacteria are able to produce sulphide which may cause corrosion of the copper in the radioactive waste storage capsules. Methanogens, on the other hand, may produce quantities of methane from various organic carbon compounds, CO 2 and H 2 . Methane may both serve as carbon source for methanotrophic microbial groups, and may also cause mobilization of radionuclides, as a result of gas discharge through fractures in the bedrock. The transition zones between the sulphate rich and methane rich waters are locations for microbial processes where the methane may serve as carbon source for sulphate reducing bacteria, which in turn would produce corrosive sulphides. It has been estimated that only 1-10 % of all the microorganisms present in the environment can be isolated and cultivated. Uncultured microorganisms can be identified and their numbers in the environment quantified by identification of specific marker genes that are essential for their functions by use of molecular methods. Methanogens, for example, can be identified by their genes for methyl coenzyme M reductase (mcrA), which is an essential enzyme involved in the production of methane. The mcrA is specifically present only in methanogenic archaea. Sulphate reducers are identified by their dissimilatory sulphite reductase genes (dsrB), which are present in and essential for all microorganisms performing dissimilatory sulphate reducing. In the GEOFUNC project, a quantitative PCR method (qPCR) was developed for the detection of methanogens and sulphate reducers. This method is based on specific quantitative detection of marker genes

Salton Sea Geothermal Field, California, as a near-field natural analog of a radioactive waste repository in salt

Science.gov (United States)

Elders, W. A.; Cohen, L. H.

1983-11-01

Since high concentrations of radionuclides and high temperatures are not normally encountered in salt domes or beds, finding an exact geologic analog of expected near-field conditions in a mined nuclear waste repository in salt will be difficult. The Salton Sea Geothermal Field, however, provides an opportunity to investigate the migration and retardation of naturally occurring U, Th, Ra, Cs, Sr and other elements in hot brines which have been moving through clay-rich sedimentary rocks for up to 100,000 years. The more than thirty deep wells drilled in this field to produce steam for electrical generation penetrate sedimentary rocks containing concentrated brines where temperatures reach 3650C at only 2 km depth. The brines are primarily Na, K, Ca chlorides with up to 25% of total dissolved solids; they also contain high conentrations of metals such as Fe, Mn, Li, Zn, and Pb. This report describes the geology, geophysics and geochemistry of this system as a prelude to a study of the mobility of naturally occurring radionuclides and radionuclide analogs within it.

The flushing and exchange of the South China Sea derived from salt and mass conservation

Science.gov (United States)

Liu, Yang; Bye, John A. T.; You, Yuzhu; Bao, Xianwen; Wu, Dexing

2010-07-01

In this paper, we use two kinds of hydrographic data, historical cruise data, Array for Real-time Geostrophic Oceanography (Argo) float data, and atmospheric data to study the water exchange between the South China Sea (SCS) and the Pacific Ocean through the Luzon Strait. The annual mean distributions of temperature and salinity at five different levels in the SCS and the adjacent Pacific Ocean are presented, which indicate the occurrence of active water exchange through the Luzon Strait. The flushing and exchange of the SCS are then determined by the application of salt and mass conservation in a multi-layered thermohaline system, using an estimate of the net rainfall obtained from reanalysis data. The results show that the annual mean flushing time is 44±8 months with an inflow rate of 11±2 Sv (1 Sv=10 6 m 3 s -1), part of which recirculates at a deeper level through the Luzon Strait, the remainder (6±2 Sv) forming the SCS throughflow. The diffusive influx of salt is also estimated and accounts for about 10% of the total influx, and hence advection dominates over diffusion in the water exchange through the Luzon Strait. The seasonal cycle of exchange shows a maximum in autumn and winter of about twice the annual mean rate.

Dose-response testing with nickel sulphate using the TRUE test in nickel-sensitive individuals. Multiple nickel sulphate patch-test reactions do not cause an 'angry back'

DEFF Research Database (Denmark)

Andersen, Klaus Ejner; Lidén, C; Hansen, J

1993-01-01

The aim of this study was to employ the TRUE test assay to confirm the presence or absence of the 'angry back' phenomenon, i.e. that a strong positive patch-test reaction heightens adjacent patch-test response. In addition, we wished to establish the dose-response relationship for nickel sulphate...... back' phenomenon was not apparent in this study, as the spill-over effect was not statistically significant. Strong reactions to high concentrations of nickel sulphate did not enhance the response to adjacent lower concentrations of nickel sulphate....

Using a dual isotopic approach to trace sources and mixing of sulphate in Changjiang Estuary, China

International Nuclear Information System (INIS)

Li Siliang; Liu Congqiang; Patra, Sivaji; Wang Fushun; Wang Baoli; Yue Fujun

2011-01-01

Highlights: → Changjiang Estuary plays an important role in transportation of the water and solute. → The dual isotopic method could be used to understand sulfate biogeochemistry in estuaries. → Mixing processes should be a major factor involved in the distribution of water and sulphate. → Sulphate in the Changjiang River mainly derived from atmospheric deposition, evaporite dissolution and sulphide oxidation. - Abstract: The dual isotopic compositions of dissolved SO 4 2- in aquatic systems are commonly used to ascertain SO 4 2- sources and possible biogeochemical processes. In this study, the physical parameters, major anions and isotopic compositions of SO 4 2- in water samples from Changjiang River (Nanjin) to the East Sea in Changjiang Estuary were determined. The salinity ranged from 0 per mille to 32.3 per mille in the estuary water samples. The Cl - ,SO 4 2- concentrations and δ 18 O-H 2 O values followed the salinity variations from freshwater to seawater, which indicated that mixing processes might be a major factor involved in the distribution of water and solutes. The contents and isotopic compositions of SO 4 2- suggested that atmospheric deposition, evaporite dissolution and sulphide oxidation were the major sources of dissolved SO 4 2- in the freshwater of Changjiang River. In addition, the mixing model calculated by contents and isotopic compositions of SO 4 2- indicated that the mixing of freshwater and sea water was the major factor involved in SO 4 2- distribution in Changjiang Estuary. However, slightly elevated δ 18 O-SO 4 values were observed in the turbidity maximum zone, which suggested that biological processes might affect the O isotopic compositions of SO 4 2- there.

Alternative substrates of bacterial sulphate reduction suitable for the biological-chemical treatment of acid mine drainage

Directory of Open Access Journals (Sweden)

Alena Luptakova

2012-12-01

Full Text Available The impacts of AMD pollution on biological systems are mostly severe and the problem may persist from many decadesto thousands of years. Consequently AMD prior to being released into the environment must be treated to meet government standardsfor the amount of metal and non-metal ions contained in the water. One of the best available technologies for the removal of metals fromAMD is precipitation as metal sulphides. SRB applications for AMD treatment involve a few principal stages. The first stageis the cultivation of SRB i.e. the bacterial sulphate reduction. At the laboratory conditions the sodium lactate is the energetic substratefor the growth of bacteria. Its price is not economic for the application in the practice and is needed investigate the alternativesubstitutes. The aim of this work was the cultivation of SRB using the selected energetic substrates such as: calcium lactate, ethanol,saccharose, glucose and whey. Experimental studies confirm that in the regard to the amount of reduced sulphates the calcium lactateand ethanol are the best alternative substrates for the bacterial sulphate-reduction.

Corrosion Performance of Inconel 625 in High Sulphate Content

Science.gov (United States)

Ismail, Azzura

2016-05-01

Inconel 625 (UNS N06625) is a type of nickel-chromium-molybdenum alloy with excellent corrosion resistance in a wide range of corrosive media, being especially resistant to pitting and crevice corrosion. However, in aggressive environment, Inconel 625 will suffer corrosion attack like other metals. This research compared the corrosion performance of Inconel 625 when exposed to higher sulphate content compared to real seawater. The results reveal that Inconel 625 is excellent in resist the corrosion attack in seawater. However, at increasing temperature, the corrosion resistance of this metal decrease. The performance is same in seawater with high sulphate content at increasing temperature. It can be concluded that sulphate promote perforation on Inconel 625 and become aggressive agents that accelerate the corrosion attack.

Polyferric sulphate: preparation, characterisation and application in coagulation experiments.

Science.gov (United States)

Zouboulis, A I; Moussas, P A; Vasilakou, F

2008-07-15

The process of coagulation is a core environmental protection technology, which is mainly used in the water or wastewater treatment facilities. Research is now focused on the development of inorganic pre-polymerised coagulants. A characteristic example is PFS (polyferric sulphate), a relatively new pre-polymerised inorganic coagulant with high cationic charge. In this paper, the role of major parameters, including temperature, types of chemical reagents, ratio r=[OH]/[Fe], rate of base addition in the preparation stages of PFS were investigated. Furthermore, the prepared PFS was characterised based on typical properties, such as the percentage of the polymerised iron present in the compound, z-potential, pH, etc. Moreover, dynamics of coagulation process were examined by means of the Photometric Dispersion Analyzer (PDA). Finally, the coagulation efficiency of PFS in treating kaolin suspension and biologically pre-treated wastewater was evaluated in comparison with the respective conventional coagulant agent. The results indicate that certain parameters, such as the r value, the rate of base addition and the duration and temperature of the polymerisation stage, significantly affected the properties of the PFS. Additionally, the prepared PFS polymerised coagulants exhibit a significantly better coagulation performance than the respective non-polymerised one, i.e. ferric sulphate.

Preliminary isotopic study of Lake Asal system (Republic of Djibouti)

International Nuclear Information System (INIS)

Fontes, J.C.; Zuppi, G.M.; Florkowski, T.; Pouchan, P.

1979-01-01

The saline Lake Asal at 155 m below sea level in the Afar Rift (Republic of Djibouti) is fed mainly by sea water. In spite of the intense evaporation (about 3 m annually), the 18 O and deuterium enrichments of the lake water are relatively low, because of the reduced activity of water as a consequence of the high salt content. Isotopic balance of the lake, as well as lithium and sulphate balances, support the hypothesis of leakages from the lake of about 15 to 20% of the inflow. (author)

Specific effects of certain salts on nitrogen metabolism of young corn seedlings

Directory of Open Access Journals (Sweden)

Mohammad Hatata

2014-01-01

Full Text Available The effect of sodium and magnesium chlorides and sulphates on nitrogen metabolism of corn seedlings and their constituent parts have been studied. Treatment with all salts led to a decrease in the nitrogen content of the seedling as a whole, and the decrease became more pronounced with the increase of salt concentration, though these concentrations were too low to induce any osmotic action. The same trend of changes was noticed as regards nonprotein-N, whereas the opposite was recorded in reference to the changes; of protein-N. Higher concentrations of the salt solutions led to leaching out of more nonprotein-N than did lower concentrations. The study of the distribution of nitrogenous constituents among the different organs of the seedling showed that while the total-N content of the whole seedling decreased with the increase of salt concentration, the total-N content of the roots decreased markedly, and the total-N content of the tops decreased also but less whereas, the total-N content of the grains increased with the increase of salt concentration as compared with that in the control. As a result of disturbances of nitrogen metabolism under salinization, more ammonia and amides were accumulated in all seedling organs.

Study of the sulphate expansion phenomenon in concrete: behaviour of the cemented radioactive wastes containing sulphate

International Nuclear Information System (INIS)

Li, Guanshu

1994-01-01

Sulphate attack is one of the major degradation processes of concrete. It is especially important in storing cemented radioactive wastes containing sulphate. In this thesis, we have thoroughly investigated the degradation mechanisms of cemented radioactive wastes by sulphate. The CaO-Al 2 O 3 -SO 3 -H 2 O systems with and without alkalis are studied. For the system without alkalis, experimental results show that it is the formation of a secondary ettringite under external water supply by steric effect that causes the expansion. For the system with alkalis, the ettringite does not appear while a new mineral called 'U', a sodium-substituted AFm phase is detected. This phase is shown to be responsible for the expansion and destruction of the specimens. The conditions for the formation, the product of solubility and many means of its synthesis are discussed, and a complete list of the inter-reticular distances file is given. The behaviour of the different types of cemented wastes containing sulphate are then studied with a special focus on the U phase on entity which was heretofore very little understood. The following three hypothetical mechanisms of sulphate expansion are proposed: the formation of the secondary U phase, the transformation of the U phase to the ettringite and the topochemical hydration of thenardite into mirabilite. Experiments on a simplified system have demonstrated clearly that the formation of the secondary U phase can induce enormous expansion by steric effect, this justifying the first assumption. Simulation by the mass and volume balances is carried out thereafter and enables us to estimate the expansion induced by the formation of the secondary U phase in the cemented wastes. The second assumption is also well verified by a series of leaching tests in different solutions on mixtures containing the U phase. On the basis of the analysis of the specimens under leaching, it has been assumed that the expansion is associated with the

Organic aerosols and inorganic species from post-harvest agricultural-waste burning emissions over northern India: impact on mass absorption efficiency of elemental carbon.

Science.gov (United States)

Rajput, Prashant; Sarin, M M; Sharma, Deepti; Singh, Darshan

2014-01-01

Atmospheric PM2.5 (particulate matter with aerodynamic diameter of ≤ 2.5 μm), collected from a source region [Patiala: 30.2 °N; 76.3 °E; 250 m above mean sea level] of emissions from post-harvest agricultural-waste (paddy-residue) burning in the Indo-Gangetic Plain (IGP), North India, has been studied for its chemical composition and impact on regional atmospheric radiative forcing. On average, organic aerosol mass accounts for 63% of PM2.5, whereas the contribution of elemental carbon (EC) is ∼3.5%. Sulphate, nitrate and ammonium contribute up to ∼85% of the total water-soluble inorganic species (WSIS), which constitutes ∼23% of PM2.5. The potassium-to-organic carbon ratio from paddy-residue burning emissions (KBB(+)/OC: 0.05 ± 0.01) is quite similar to that reported from Amazonian and Savanna forest-fires; whereas non-sea-salt-sulphate-to-OC ratio (nss-SO4(2-)/OC: 0.21) and nss-SO4(2-)/EC ratio of 2.6 are significantly higher (by factor of 5 to 8). The mass absorption efficiency of EC (3.8 ± 1.3 m(2) g(-1)) shows significant decrease with a parallel increase in the concentrations of organic aerosols and scattering species (sulphate and nitrate). A cross plot of OC/EC and nss-SO4(2-)/EC ratios show distinct differences for post-harvest burning emissions from paddy-residue as compared to those from fossil-fuel combustion sources in south-east Asia.

The effect of water on the sulphation of limestone

Energy Technology Data Exchange (ETDEWEB)

Chunbo Wang; Lufei Jia; Yewen Tan; E.J. Anthony [North China Electric Power University, Baoding City (China). School of Energy and Power Engineering

2010-09-15

A series of tests was conducted in a thermogravimetric analyzer (TGA) to study the sulphation behaviour of limestone in the presence of water over the temperature range of 800-850{sup o}C. Four different Canadian limestones, all with a particle size range of 75-425 {mu}m, were sulphated using a synthetic flue gas with a composition of 15% CO{sub 2}, 3% O{sub 2}, 0% or 10% H{sub 2}O, 1750 ppm SO{sub 2} and the balance N{sub 2}. Water was shown to have a significant promotional effect on sulphation, especially in the diffusion-controlled stage. However, the effect of water during the kinetic-controlled stage appeared to be much less pronounced. Based on these results, it is proposed that the presence of water leads to the transient formation of Ca(OH){sub 2} as an intermediate, which in turn reacts with SO{sub 2} at a faster rate than CaO does. Alternatively stated, it appears that H{sub 2}O acts as catalyst for the sulphation reaction of CaO. 30 refs., 8 figs., 3 tabs.

Tropical vegetation evidence for rapid sea level changes associated with Heinrich Events

Energy Technology Data Exchange (ETDEWEB)

Gonzalez, Catalina; Dupont, Lydie M, E-mail: catalina@uni-bremen.d, E-mail: dupont@uni-bremen.d [MARUM - Centre for Marine Environmental Sciences, University of Bremen, Leobener Strasse, D-28359 Germany (Germany)

2010-03-15

A Cariaco Basin pollen record shows the development of tropical salt marshes during marine isotope stage 3. Rapid and abrupt expansions of salt marsh vegetation in tropical South America are associated with north Atlantic Heinrich Events stadials (HE-stadials). Intervals of salt marsh expansion have an internal structure, which consists of a recurrent alternation of species that starts with pollen increments of Chenopodiaceae, that are followed by increments of grasses, and subsequently by increments of Cyperaceae. This pattern suggests a successional process that is determined by the close relationship between sea-level and plant community dynamics. The salt tolerant Chenopodiaceae, indicate hypersaline intertidal environments, which were most likely promoted by extremely dry atmospheric conditions. Rapid sea-level rise characterizes the onset of HE-stadials, causing the continued recruitment of pioneer species, which are the only ones tolerating rapid rates of disturbance. Once sea-level rise decelerates, marsh plants are able to trap and stabilize sediments, favouring the establishment of more competitive species. These results add to the scarce knowledge on the dynamics of tropical salt marsh ecosystems, and provide independent paleoclimatic evidence on sea-level changes following Antarctic climate variability.

The action of diazoxide and minoxidil sulphate on rat blood vessels: a comparison with cromakalim.

Science.gov (United States)

Newgreen, D. T.; Bray, K. M.; McHarg, A. D.; Weston, A. H.; Duty, S.; Brown, B. S.; Kay, P. B.; Edwards, G.; Longmore, J.; Southerton, J. S.

1990-01-01

1. The actions of diazoxide and minoxidil sulphate have been compared with those of cromakalim in rat aorta and portal vein. 2. Diazoxide and minoxidil sulphate hyperpolarized the rat portal vein in a similar manner to cromakalim. 3. Cromakalim, diazoxide and minoxidil sulphate increased 42K and 86Rb efflux from rat portal vein, although minoxidil sulphate had only a small effect on 86Rb efflux. 4. Cromakalim, diazoxide and minoxidil sulphate increased 42K efflux from rat aorta but only cromakalim and diazoxide increased 86Rb efflux from this tissue. 5. Glibenclamide inhibited the relaxant actions of cromakalim, diazoxide and minoxidil sulphate on rat aorta and the increase in 42K efflux produced by these agents in this tissue. 6. Diazoxide relaxed an 80 mM KCl-induced contraction of rat aorta, whilst cromakalim and minoxidil sulphate were without effect. 7. Cromakalim, diazoxide and minoxidil sulphate had no effect on cyclic AMP or cyclic GMP concentrations in rat aorta. 8. It is concluded that diazoxide and minoxidil sulphate like cromakalim exhibit K+ channel opening properties in vascular smooth muscle. Diazoxide exerts an additional inhibitory action not related to the production of cyclic AMP or cyclic GMP. The action of minoxidil sulphate may be primarily located at a K+ channel which is relatively impermeable to 86Rb. PMID:2167738

Digestion of Alumina from Non-Magnetic Material Obtained from Magnetic Separation of Reduced Iron-Rich Diasporic Bauxite with Sodium Salts

Directory of Open Access Journals (Sweden)

Guanghui Li

2016-11-01

Full Text Available Recovery of iron from iron-rich diasporic bauxite ore via reductive roasting followed by magnetic separation has been explored recently. However, the efficiency of alumina extraction in the non-magnetic materials is absent. In this paper, a further study on the digestion of alumina by the Bayer process from non-magnetic material obtained after magnetic separation of reduced iron-rich diasporic bauxite with sodium salts was investigated. The results indicate that the addition of sodium salts can destroy the original occurrences of iron-, aluminum- and silicon-containing minerals of bauxite ore during reductive roasting. Meanwhile, the reactions of sodium salts with complex aluminum- and silicon-bearing phases generate diaoyudaoite and sodium aluminosilicate. The separation of iron via reductive roasting of bauxite ore with sodium salts followed by magnetic separation improves alumina digestion in the Bayer process. When the alumina-bearing material in bauxite ore is converted into non-magnetic material, the digestion temperature decreases significantly from 280 °C to 240 °C with a nearly 99% relative digestion ratio of alumina.

Long-term effects of operating temperature and sulphate addition on the methanogenic community structure of anaerobic hybrid reactors.

Science.gov (United States)

Pender, Seán; Toomey, Margaret; Carton, Micheál; Eardly, Dónal; Patching, John W; Colleran, Emer; O'Flaherty, Vincent

2004-02-01

The diversity, population dynamics, and activity profiles of methanogens in anaerobic granular sludges from two anaerobic hybrid reactors treating a molasses wastewater both mesophilically (37 degrees C) and thermophilically (55 degrees C) during a 1081 day trial were determined. The influent to one of the reactors was supplemented with sulphate, after an acclimation period of 112 days, to determine the effect of competition with sulphate-reducing bacteria on the methanogenic community structure. Sludge samples were removed from the reactors at intervals throughout the operational period and examined by amplified ribosomal DNA (rDNA) restriction analysis (ARDRA) and partial sequencing of 16S rRNA genes. In total, 18 operational taxonomic units (OTUs) were identified, 12 of which were sequenced. The methanogenic communities in both reactors changed during the operational period. The seed sludge and the reactor biomass sampled during mesophilic operation, both in the presence and absence of sulphate, was characterised by a predominance of Methanosaeta spp. Following temperature elevation, the dominant methanogenic sequences detected in the non-sulphate supplemented reactor were closely related to Methanocorpusculum parvum. By contrast, the dominant OTUs detected in the sulphate-supplemented reactor upon temperature increase were related to the hydrogen-utilising methanogen, Methanobacterium thermoautotrophicum. The observed methanogenic community structure in the reactors correlated with the operational performance of the reactors during the trial and with physiological measurements of the reactor biomass. Both reactors achieved chemical oxygen demand (COD) removal efficiencies of over 90% during mesophilic operation, with or without sulphate supplementation. During thermophilic operation, the presence of sulphate resulted in decreased reactor performance (effluent acetate concentrations of >3000 mg/l and biogas methane content of acetate at 55 degrees C was

The role of succulent halophytes in the water balance of salt marsh rodents.

Science.gov (United States)

Coulombe, Harry N

1970-09-01

The role of succulent halophytes in the water balance and ecology of salt marsh rodents is dependent upon an evaluation of the composition of the available sources and the physiological properties of their potential consumers. Studies of the osmotic properties of succulent halophytes from southern California coastal salt marshes are presented, together with experiments regarding the utilization of Common Pickleweed (Salicornia virginica L.) by indigenous populations of cricetid rodents (harvest mouse Reithrodontomys megalotis limicola Von Bloecker, and meadow-mouse Microtus californicus stephensi Von Bloecker). These data are discussed in relation to other available information concerning the ecology of coastal salt marshes, particularly in western North America.Extruded sap of Common Pickleweed was found to have a mean total osmotic pressure (TOP) of 1,450 mOsm/liter, with an average chloride ion content of 876 mEq/liter (about 70% of the TOP). A related species, Salicornia subterminale, had a slightly lower TOP (1,300 mOsm/liter), of which about 29% was accounted for by chloride ion concentration. Sea Blight (Suaeda fruticosa) was the only species in which the TOP correlated with the distance from the tide level; sap TOP increased away from the lagoon's edge. In both Sea Blight and Common Pickle weed, TOP was not directly related to chloride content, indicating the importance of other osmotically active solutes.Harvest mice were placed on three experimental regimes: 1) millet seeds only, 2) pickleweed only, and 3) pickleweed and millet seed. Meadow mice were tested on the last regime only. Harvest mice survived best on a strict millet seed diet; when Salicornia was consumed to a detectable extent, the mice did not survive. Meadow mice, however, could survive using Salicornia as a dietary source in conjunction with seeds. Kidney electrolyte concentrating abilities indicated that harvest mice should be able to utilize pickleweed; this was not confirmed in my

First salt making in Europe: an overview from Neolithic times

Directory of Open Access Journals (Sweden)

Olivier Weller

2015-12-01

Full Text Available This paper deals with the origin of salt production and discusses different approaches ranging from technology, ethnoarchaeology and paleoenvironmental studies to chemical analyses. Starting from the current research on the Neolithic exploitation of salt in Europe, we examine the types and nature of the salt resources (sea water, salt springs, soil or rock, the diversity of archaeological evidence of forms of salt working. We also scrutinize the types of production for these early forms of salt exploitation, with or without the use of crudely fired clay vessels (briquetage. Finally, we contextualise the socio-economic dimensions and highlight both the diversity of salt products and their characteristics, which go well beyond dietary roles.

Adenylate cyclase activity in fish gills in relation to salt adaptation

International Nuclear Information System (INIS)

Guibbolini, M.E.; Lahlou, B.

1987-01-01

The influence of salt adaptation on specific adenylate cyclase activity (measured by conversion of [α- 32 P] - ATP into [α- 32 P] - cAMP) was investigated in gill plasma membranes of rainbow trout (Salmo gairdneri) adapted to various salinities (deionized water, DW; fresh water, FW; 3/4 sea water, 3/4 SW; sea water, SW) and in sea water adapted- mullet (Mugil sp.). Basal activity declined by a factor of 2 in trout with increasing external salinity (pmoles cAMP/mg protein/10 min: 530 in DW, 440 in FW, 340 in 3/4 SW; 250 in SW) and was very low in SW adapted-mullet: 35. The Km for ATP was similar (0.5 mM) in both FW adapted- and SW adapted- trout in either the absence (basal activity) or in the presence of stimulating agents (isoproterenol; NaF) while the Vm varied. Analysis of stimulation ratios with respect to basal levels of the enzyme showed that hormones and pharmacological substances (isoproterenol, NaF) display a greater potency in high salt than in low salt adapted- fish gills. In contrast, salt adaptation did not have any effect on the regulation of adenylate cyclase by PGE 1 . These results are interpreted in relation to the general process of osmoregulation. 27 references, 6 figures

Nuclear waste in sea or salt? No, wrong

International Nuclear Information System (INIS)

Damveld, H.; Van Duin, S.; Bannink, D.

1994-04-01

Eighteen years of successful action against ocean dumping and storage of nuclear waste in salt domes are reviewed for the Dutch situation. The aim of this book is to hand some support to those who want to act against trial borings, in particular the people living close to the most important salt domes in the Netherlands: Ternaard, Zuidwending, Pieterburen, Onstwedde, Winschoten, Schoonlo and Gasselte-Drouwen. In 1976 the Interdepartmental Commission on Nuclear Energy with its subcommission Radioactive Substances (ICK-RAS) was installed, along with a number of working groups, responsible for research. From 1978 onwards ocean dumping operations were accompanied by blockades and legal procedures, which led to a situation of the last dumping in 1982. The Dutch government then focused on nuclear waste storage in salt domes for which the OPLA research program was started. OPLA is the Dutch abbreviation for Storage on Land. The final report (phase 1 and 1a) of OPLA was published on 15 October 1993 as annex to the Dossier Nuclear Energy of the Dutch government. It has been decided that phase 1a is not followed by trial drillings, as planned before. Some critical remarks are made regarding the rounds of public participation and the notion of permanent retrievability of stored nuclear waste. Extensive use has been made of documentation from the Dutch government and parliament, and other literature and information sources

Sources of household salt in South Africa.

Science.gov (United States)

Jooste, Pieter L

2005-01-01

Marketing of non-iodized salt through unconventional distribution channels is one of the factors weakening the national salt iodization program in South Africa. The aim of this study was therefore to quantify the various sources of household salt, and to relate this information to socio-economic status. Questionnaire information was collected by personal interview during home visits from a multistage, cluster, probability sample of 2164 adults representative of the adult population. Nationally 77.7% of households obtained their table salt from the typical food shops distributing iodized salt. However, in the nine different provinces between 8 and 37.3% of households used unconventional sources, distributing mainly non-iodized salt, to obtain their household salt. These alternative sources include distributors of agricultural salt, small general dealer shops called spaza shops, in peri-urban and rural townships, street vendors and salt saches placed in the packaging of maize meal bags. Country-wide around 30% of low socio-economic households obtained their salt from unconventional sources compared to less than 5% in high socio-economic households, emphasizing the vulnerability of low socio-economic groups to the use of non-iodized salt. Intervention strategies should mobilize all role players involved in unconventional marketing channels of household salt to provide only iodized salt to consumers, as required by law.

Performance of cement solidification with barium for high activity liquid waste including sulphate

International Nuclear Information System (INIS)

Waki, Toshikazu; Yamada, Motoyuki; Horikawa, Yoshihiko; Kaneko, Masaaki; Saso, Michitaka; Haruguchi, Yoshiko; Yamashita, Yu; Sakai, Hitoshi

2009-01-01

The target liquid waste to be solidified is generated from PWR primary loop spent resin treatment with sulphate acid, so, its main constituent is sodium sulphate and the activity of this liquid is relatively high. Waste form of this liquid waste is considered to be a candidate for the subsurface disposal. The disposed waste including sulphate is anticipated to rise a concentration of sulphate ion in the ground water around the disposal facility and it may cause degradation of materials such as cement and bentonite layer and comprise the disposal facility. There could be two approaches to avoid this problem, the strong design of the disposal facility and the minimization of sulphaste ion migration from the solidified waste. In this study, the latter approach was examined. In order to keep the low concentration of sulphate ion in the ground water, it is effective to make barium sulphate by adding barium compound into the liquid waste in solidification. However, adding equivalent amount of barium compound with sulphate ion causes difficulty of mixing, because production of barium sulphate causes high viscosity. In this study, mixing condition after and before adding cement into the liquid waste was estimated. The mixing condition was set with consideration to keep anion concentration low in the ground water and of mixing easily enough in practical operation. Long term leaching behavior of the simulated solidified waste was also analyzed by PHREEQC. And the concentration of the constitution affected to the disposal facility was estimated be low enough in the ground water. (author)

Salt nuclei, wind and daily rainfall in Hawaii

Energy Technology Data Exchange (ETDEWEB)

Woodcock, A H; Mordy, W A

1955-01-01

The discovery of large sea-salt particulates at cloud levels led to the hypothesis that these particles act as nuclei on which raindrops initially form within clouds and to the suggestion that the amount of rainfall on an oceanic island might be a function of the number of the salt particles in the air. Exploratory observations of rain and airborne salt in Hawaii, which were intended to test this suggestion, are presented and discussed. These observations do not prove that greater numbers of salt nuclei are related to greater amounts of rain. They do, however, indicate that such a relationship may exist, and that additional field studies should be made which utilize the pertinent results of the present study.

Salbutamol sulphate-ethylcellulose microparticles: formulation and in-vitro evaluation with emphasis on mathematical approaches

Directory of Open Access Journals (Sweden)

G Murtaza

2009-10-01

Full Text Available "n "nBackground and the purpose of the study: This study reports the laboratory optimization for the preparation of salbutamol sulphate-ethylcellulose microparticles by a non-solvent addition coacervation technique through adjustment of the ratio of salbutamol sulphate to ethylcellulose. The variation of drug release between the microparticles and tabletted microparticles was also investigated. "nMethods: In vitro release profiles of developed microparticles and tabletted microparticles were studied using USP XXIV dissolution apparatus I and II, respectively, in 450 ml double distilled water at 50 rpm maintained at 37°C. "nResults: White microparticles with no definite shape having good entrapment efficiency (96.68 to 97.83% and production yield (97.48 ± 1.21 to 98.35 ± 1.08% were obtained. In this investigation, initial burst effect was observed in the drug release behavior. The rate of drug release from microparticles decreased as the concentration of polyisobutylene was increased from 6% to 12% during microencapsulation. The release pattern of tabletted microparticles was affected significantly (p < 0.05 by the addition of hydroxy propyl methyl cellulose (HPMC as excepient and insignificantly (p > 0.05 by the type of dissolution media and stirring speed. Tabletted microparticles showed good stability and reproducibility. Ethylcellulose was found to be compatible with salbutamol sulphate. The drug release from all formulations was best fit to Higuchi's equation and the mechanism of drug release was anomalous diffusion from all formulations. "nConclusion: The results of this study suggest that by using ethylcellulose it is possible to design a single-unit, sustained-release oral dosage form of salbutamol sulphate for indication of twice a day.

Influence of Silica Fume Addition in the Long-Term Performance of Sustainable Cement Grouts for Micropiles Exposed to a Sulphate Aggressive Medium

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José Marcos Ortega

2017-08-01

Full Text Available At present, sustainability is of major importance in the cement industry, and the use of additions such as silica fume as clinker replacement contributes towards that goal. Special foundations, and particularly micropiles, are one of the most suitable areas for the use of sustainable cements. The aim of this research is to analyse the effects in the very long-term (for 600 days produced by sulphate attack in the microstructure of grouts for micropiles in which OPC (ordinary Portland cement has been replaced by 5% and 10% silica fume. This line of study is building on a previous work, where these effects were studied in slag and fly ash grouts. Grouts made using a commercial sulphate-resisting Portland cement were also studied. The non-destructive impedance spectroscopy technique, mercury intrusion porosimetry, and Wenner resistivity testing were used. Mass variation and the compressive strength have also been analysed. Apparently, impedance spectroscopy is the most suitable technique for studying sulphate attack development. According to the results obtained, grouts for micropiles with a content of silica fume up to 10% and exposed to an aggressive sulphate medium, have a similar or even better behaviour in the very long-term, compared to grouts prepared using sulphate-resisting Portland cement.

Microbial diversity in cold seep sediments from the northern South China Sea

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Yong Zhang

2012-05-01

Full Text Available South China Sea (SCS is the largest Western Pacific marginal sea. However, microbial studies have never been performed in the cold seep sediments in the SCS. In 2004, “SONNE” 177 cruise found two cold seep areas with different water depth in the northern SCS. Haiyang 4 area, where the water depth is around 3000 m, has already been confirmed for active seeping on the seafloor, such as microbial mats, authigenic carbonate crusts and bivalves. We investigated microbial abundance and diversity in a 5.55-m sediment core collected from this cold seep area. An integrated approach was employed including geochemistry and 16S rRNA gene phylogenetic analyses. Here, we show that microbial abundance and diversity along with geochemistry profiles of the sediment core revealed a coupled reaction between sulphate reduction and methane oxidation. Acridine orange direct count results showed that microbial abundance ranges from 105 to 106 cells/g sediment (wet weight. The depth-related variation of the abundance showed the same trend as the methane concentration profile. Phylogenetic analysis indicated the presence of sulphate-reducing bacteria and anaerobic methane-oxidizing archaea. The diversity was much higher at the surface, but decreased sharply with depth in response to changes in the geochemical conditions of the sediments, such as methane, sulphate concentration and total organic carbon. Marine Benthic Group B, Chloroflexi and JS1 were predominant phylotypes of the archaeal and bacterial libraries, respectively.

The role of bile salt toxicity in the pathogenesis of bile duct injury after non-heart-beating porcine liver transplantation

NARCIS (Netherlands)

Yska, Marit J.; Buis, Carlijn I.; Monbaliu, Diethard; Schuurs, Theo A.; Gouw, Annette S. H.; Kahmann, Olivier N. H.; Visser, Dorien S.; Pirenne, Jacques; Porte, Robert J.

2008-01-01

Background. Intrahepatic bile duct strictures are a serious complication after non-heart-beating (NHB) liver transplantation. Bile salt toxicity has been identified as an important factor in the pathogenesis of bile duct injury and cholangiopathies. The role of bile salt toxicity in the development

Interplay of salt dynamics, sea-level change and climate on the depositional evolution of a Paleogene economic coal bearing salt rim syncline, Schoeningen, Germany

Energy Technology Data Exchange (ETDEWEB)

Osman, A.; Pollok, L.; Brandes, C.; Winsemann, J. [Leibniz Univ. Hannover (Germany). Inst. fuer Geologie

2013-08-01

The Paleogene basin fill (maximum 300 m thick) of the Schoeningen rim syncline in northern Germany is well known for its economic lignitic coal deposits. The fill provides an example of the interaction of basin subsidence, sea-level, and climate changes on depositional environment and gives insight into the development of the coal seams within a sequence stratigraphic context. The rim syncline records thirteen Lower to Middle Eocene coal seams with intervening clastic layers that were deposited during a long-lived transgression of the Central German Estuary, which lasted until the Late Oligocene (Standke, 2008). The previous analysis of the rim syncline fill has primarily focused on coal deposits, their lateral extent and paleo-botanical habitat. In this work, 357 lithologic logs were calibrated to outcrop profiles and integrated with previous studies to provide a facies analysis and sequence stratigraphy interpretation of the syncline fill. This improves understanding of the depositional environments of the lesser-studied clastics that intervene the coals (Osman et al., in review). Four 3{sup rd} order sequences are recorded in the Lower to Middle Eocene basin fill. Sequences 1 and 2 document the interplay of sands and coals within a transgressive estuarine phase. The sands show a regime change from tide- to more wave-dominated estuarine conditions before a turnaround to a regressive deltaic phase. This succession typifies an incised valley fill. However, the accommodation space generated for the initial estuary development is thought to have originated via continual salt withdrawal (Brandes et al. 2012) instead of by incision during relative sea-level fall. The observed tide to wave estuary regime change is linked to increased subsidence rates at 57 Ma that generated a higher tidal prism. As the subsidence rates slowed and the syncline broadened, the tidal prism decreased, leading to the development of more wave-dominated facies. The intervening coal seams

Salt Rejection of Non-Ionic Polymeric Membranes

DEFF Research Database (Denmark)

Bo, P.; Stannett, V.

1976-01-01

A modified solution-diffusion model for the description of salt and water transport through homogeneous membranes is introduced. It is compared with the current solution-diffusion model and the combined flow-diffusion model for the description of transport under reverse osmosis conditions....... The advantage of the modified description over the current solution-diffusion model is the inclusion of a salt-water coupling transport coefficient which allows the description to be extended to membranes of high water permeability (high water content). The advantage of the modified solution-diffusion model...

Development of melt compositions for sulphate bearing high level waste

International Nuclear Information System (INIS)

Jahagirdar, P.B.; Wattal, P.K.

1997-09-01

The report deals with the development and characterization of vitreous matrices for sulphate bearing high level waste. Studies were conducted in sodium borosilicate and lead borosilicate systems with the introduction of CaO, BaO, MgO etc. Lead borosilicate system was found to be compatible with sulphate bearing high level wastes. Detailed product evaluation carried on selected formulations is also described. (author)

Chemical composition of rainwater at Taita, New Zealand, 1956-1958

Energy Technology Data Exchange (ETDEWEB)

Miller, R B

1961-01-01

Rainwater has been collected monthly for three years at the Taita experimental station, 5 miles from the coast near Wellington, and analysed for the main elements present. The salt found, excluding bicarbonate, averaged 190 lb/ac/yr (212 kg/ha/yr) of which nearly 80% was sodium and chloride. Sulphate, 22 lb/ac/yr, and magnesium, 10 lb/ac/yr, were next in amount, followed by potassium and calcium with 6 lb/ac/yr each. Phosphate was very low (less than 1 lb/ac/yr). Total nitrogen was measured for a period and found to be double the inorganic plus albuminoid nitrogen. Accessions to the soil of nitrogen are probably not less than 3 lb/ac/yr. The ionic ratios showed that in periods with southerly storms the salt tended to approach the composition of sea water, and at other times calcium and potassium, and to a lesser degree magnesium and sulphate, reached higher proportions.

Effect of iron salt type and dosing mode on Fenton-based pretreatment of rice straw for enzymatic hydrolysis.

Science.gov (United States)

Gan, Yu-Yan; Zhou, Si-Li; Dai, Xiao; Wu, Han; Xiong, Zi-Yao; Qin, Yuan-Hang; Ma, Jiayu; Yang, Li; Wu, Zai-Kun; Wang, Tie-Lin; Wang, Wei-Guo; Wang, Cun-Wen

2018-06-15

Fenton-based processes with four different iron salts in two different dosing modes were used to pretreat rice straw (RS) samples to increase their enzymatic digestibility. The composition analysis shows that the RS sample pretreated by the dosing mode of iron salt adding into H 2 O 2 has a much lower hemicellulose content than that pretreated by the dosing mode of H 2 O 2 adding into iron salt, and the RS sample pretreated by the chloride salt-based Fenton process has a much lower lignin content and a slightly lower hemicellulose content than that pretreated by the sulphate salt-based Fenton process. The higher concentration of reducing sugar observed on the RS sample with lower lignin and hemicellulose contents justifies that the Fenton-based process could enhance the enzymic hydrolysis of RS by removing hemicellulose and lignin and increasing its accessibility to cellulase. FeCl 3 ·6H 2 O adding into H 2 O 2 is the most efficient Fenton-based process for RS pretreatment. Copyright © 2018 Elsevier Ltd. All rights reserved.

The contribution of mangrove expansion to salt marsh loss on the Texas Gulf Coast.

Science.gov (United States)

Armitage, Anna R; Highfield, Wesley E; Brody, Samuel D; Louchouarn, Patrick

2015-01-01

Landscape-level shifts in plant species distribution and abundance can fundamentally change the ecology of an ecosystem. Such shifts are occurring within mangrove-marsh ecotones, where over the last few decades, relatively mild winters have led to mangrove expansion into areas previously occupied by salt marsh plants. On the Texas (USA) coast of the western Gulf of Mexico, most cases of mangrove expansion have been documented within specific bays or watersheds. Based on this body of relatively small-scale work and broader global patterns of mangrove expansion, we hypothesized that there has been a recent regional-level displacement of salt marshes by mangroves. We classified Landsat-5 Thematic Mapper images using artificial neural networks to quantify black mangrove (Avicennia germinans) expansion and salt marsh (Spartina alterniflora and other grass and forb species) loss over 20 years across the entire Texas coast. Between 1990 and 2010, mangrove area grew by 16.1 km(2), a 74% increase. Concurrently, salt marsh area decreased by 77.8 km(2), a 24% net loss. Only 6% of that loss was attributable to mangrove expansion; most salt marsh was lost due to conversion to tidal flats or water, likely a result of relative sea level rise. Our research confirmed that mangroves are expanding and, in some instances, displacing salt marshes at certain locations. However, this shift is not widespread when analyzed at a larger, regional level. Rather, local, relative sea level rise was indirectly implicated as another important driver causing regional-level salt marsh loss. Climate change is expected to accelerate both sea level rise and mangrove expansion; these mechanisms are likely to interact synergistically and contribute to salt marsh loss.

Hydrogen production under salt stress conditions by a freshwater Rhodopseudomonas palustris strain.

Science.gov (United States)

Adessi, Alessandra; Concato, Margherita; Sanchini, Andrea; Rossi, Federico; De Philippis, Roberto

2016-03-01

Hydrogen represents a possible alternative energy carrier to face the growing request for energy and the shortage of fossil fuels. Photofermentation for the production of H2 constitutes a promising way for integrating the production of energy with waste treatments. Many wastes are characterized by high salinity, and polluted seawater can as well be considered as a substrate. Moreover, the application of seawater for bacterial culturing is considered cost-effective. The aims of this study were to assess the capability of the metabolically versatile freshwater Rhodopseudomonas palustris 42OL of producing hydrogen on salt-containing substrates and to investigate its salt stress response strategy, never described before. R. palustris 42OL was able to produce hydrogen in media containing up to 3 % added salt concentration and to grow in media containing up to 4.5 % salinity without the addition of exogenous osmoprotectants. While the hydrogen production performances in absence of sea salts were higher than in their presence, there was no significant difference in performances between 1 and 2 % of added sea salts. Nitrogenase expression levels indicated that the enzyme was not directly inhibited during salt stress, but a regulation of its expression may have occurred in response to salt concentration increase. During cell growth and hydrogen production in the presence of salts, trehalose was accumulated as a compatible solute; it protected the enzymatic functionality against salt stress, thus allowing hydrogen production. The possibility of producing hydrogen on salt-containing substrates widens the range of wastes that can be efficiently used in production processes.

Catalyst of a metal heteropoly acid salt that is insoluble in a polar solvent on a non-metallic porous support and method of making

Science.gov (United States)

Wang, Yong [Richland, WA; Peden, Charles H. F. [West Richland, WA; Choi, Saemin [Richland, WA

2002-10-29

The present invention includes a catalyst having (a) a non-metallic support having a plurality of pores; (b) a metal heteropoly acid salt that is insoluble in a polar solvent on the non-metallic support; wherein at least a portion of the metal heteropoly acid salt is dispersed within said plurality of pores. The present invention also includes a method of depositing a metal heteropoly acid salt that is insoluble in a polar solvent onto a non-metallic support having a plurality of pores. The method has the steps of: (a) obtaining a first solution containing a first precursor of a metal salt cation; (b) obtaining a second solution containing a second precursor of a heteropoly acid anion in a solvent having a limited dissolution potential for said first precursor; (c) impregnating the non-metallic support with the first precursor forming a first precursor deposit within the plurality of pores, forming a first precursor impregnated support; (d) heating said first precursor impregnated support forming a bonded first precursor impregnated support; (e) impregnating the second precursor that reacts with the precursor deposit and forms the metal heteropoly acid salt.

Differential inhibition of polymorphonuclear leukocyte recruitment in vivo by dextran sulphate and fucoidan

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N. Van Osselaer

1996-01-01

Full Text Available The selectin-mediated rolling of leukocytes along the endothelial cells is a prerequisite step followed by firm adhesion and extravasation into the inflamed tissue. This initial contact can be suppressed by sulphated polysaccharides. We have studied the effect of sulphated polysaccharides on the ultimate polymorphonuclear leukocyte (PMN recruitment and plasma leakage in rabbit skin in response to intradermal injection of various inflammatory mediators. PMN infiltration evoked by various PMN chemoattractants (FMLP, C5a desArg, LTB4 and IL-8 was significantly inhibited after intravenous injection of dextran sulphate (25 mg/kg, heparin (2 × 90 mg/kg or fucoidan (1 mg/kg. PMN-dependent plasma leakage was equally well reduced by the different sulphated polymers. Vascular permeability induced by histamine or thrombin acting via a PMN-independent mechanism was not reduced. Fucoidan was the only polysaccharide able to suppress IL-1-induced PMN infiltration for 60–70%. Local administration of dextran sulphate had no effect on PMN-dependent plasma leakage. Differential inhibition of PMN recruitment was determined after injection of dextran sulphate or fucoidan depending on the type of insult. Therefore, these results suggest that different adhesion pathways are utilized during PMN recruitment in vivo in response to chemoattractants and IL-1.

The reducibility of sulphuric acid and sulphate in aqueous solution (translated from German)

International Nuclear Information System (INIS)

Grauer, R.

1990-07-01

In connection with the Swedish project for the final storage of spent fuel elements it was necessary to assess whether dissolved sulphate can corrode the copper canister without the intervention of sulphate-reducing bacteria. A simple reaction between copper and sulphate is thermodynamically impossible. On the other hand, copper can react to give copper sulphide if an additional electron donor such as iron is available. Because little specific information is available about this subject the problem was extended to the much more general question of the reducibility of sulphur in dilute aqueous solution. It is a part of the general knowledge of chemistry, and there is also unanimity about it in the geochemical literature, that purely chemical reduction of sulphate does not take place in dilute solution at temperatures below 100 degrees C. This fact is, however, poorly documented and it was therefore necessary to substantiate it by drawing on numerous individual findings from different areas of pure and applied chemistry. The investigation confirms that sulphur in dilute solution is completely inert towards chemical reducing agents and also to cathodic reduction. Thus corrosion of copper by sulphate under final-storage conditions and in the absence of sulphate reducing bacteria can be ruled out with a probability verging on certainty. (85 refs.)

Influence on ammonium-sulphate fertilizer on P-uptake by upland rice

International Nuclear Information System (INIS)

Abdullah, N; Mitrosuhardjo, M.M.

1988-01-01

A greenhouse experiment to study the influence of ammonium -sulphate fertilizer on P-uptake by Atomita I/1 rice variety on latosol soil of Pasar Jumat has been conducted. Factorial experiment consisting of eight treatments was arrange in a fully randomized design. Each treatment was replicated three times. The rate of ammonium sulphate fertilizer was equivalent to 0, 30, 60, and 90 kg N/ha, and TSP at the rate of 90 and 180 kg P/ha. Ammonium sulphate fertilizer with 2% atom 15-N and TSP with specific activity of 0.2 mCi/g P2O5 were used in the experiment. The plant was harvested 70 days after planting, It was turned out that ammonium sulphate fertilizer gave a highly significant difference (p=<0.01) of dry weight of plant. The rate of TSP did not effect significantly on plant dry weight. Ammonium sulphate fertilizer gave highly significant difference on P-uptake. Fertilizer use efficiency was in the range of 3.88 - 6.60% for 90 kg P and 2.51 - 4.46% for 180 kg P. Fertilizer-N uptake was significantly increased (p=<0.05) with the increase of N rate. Rate of fertilizer-N use efficiency was in the range of 47-60% of the applied fertilizer. (authors). 4 refs, 9 tabs

Tyrosine sulphation is not required for microvillar expression of intestinal aminopeptidase N

DEFF Research Database (Denmark)

Danielsen, E M

1988-01-01

incorporation of [35S]sulphate into aminopeptidase N and other major microvillar hydrolases by 70-85% compared with controls, indicating an inhibition of their post-translational tyrosine sulphation. In labelling experiments with [35S]methionine from 0.5 to 5 h, DCNP was tested for its possible influence...... on synthesis, processing and microvillar expression of aminopeptidase N, but no effect on any of these parameters could be detected. It can therefore be concluded that tyrosine sulphation is not required (for instance as a sorting signal) for the targeting of newly synthesized enzymes to the microvillar...

Sea ice contribution to the air-sea CO(2) exchange in the Arctic and Southern Oceans

DEFF Research Database (Denmark)

Rysgaard...[], Søren; Bendtsen, Jørgen; Delille, B.

2011-01-01

Although salt rejection from sea ice is a key process in deep-water formation in ice-covered seas, the concurrent rejection of CO(2) and the subsequent effect on air-sea CO(2) exchange have received little attention. We review the mechanisms by which sea ice directly and indirectly controls the air......-sea CO(2) exchange and use recent measurements of inorganic carbon compounds in bulk sea ice to estimate that oceanic CO(2) uptake during the seasonal cycle of sea-ice growth and decay in ice-covered oceanic regions equals almost half of the net atmospheric CO(2) uptake in ice-free polar seas. This sea......-sea CO(2) exchange during winter, and (3) release of CO(2)-depleted melt water with excess total alkalinity during sea-ice decay and (4) biological CO(2) drawdown during primary production in sea ice and surface oceanic waters....

Oxygen isotopic composition of sulphates from some mineral waters and mine waters in western Bohemia

International Nuclear Information System (INIS)

Smejkal, V.

1979-01-01

Two main genetic types of sulphate can be distinguished according to the delta 18 O(SO 4 2- ) measurements in sulphate-rich mineral and mine waters of western Bohemia - sulphates in descending mine waters and in weathered outcrops of graphitic pyrite slates from areas outside Tertiary basins, which originated in recent time by the oxidation of sulphides in the presence of atmospheric oxygen, have delta 18 O values from -2.1 to -6.1 per mille SMOW; and sulphates from springs of mineral waters of the renowned spas of Karlovy Vary, Frantiskovy Lazne and Marianske Lazne show distinctly heavier delta 18 O values - from +4.0 to +6.4 per mille, with maximum of values between +5.0 and +6.0 per mille. Similar delta 18 O values have been established in thenardites and in gypsum in Miocene claystones and in sulphates of some mine waters in the nearby Tertiary Cheb and Sokolov Basins. The presented results indicate that sulphates in mineral waters of the Karlovy Vary type originate mainly by leaching of Miocene sulphates and not by present-day oxidation of sulphidic sulphur. (author)

Possibilities of Sulphate Elimination from Mine Water

Directory of Open Access Journals (Sweden)

Heviánková Silvie

2004-12-01

Full Text Available The issue of „acid water“ (or AMD is well known in the world for some centuries. In the Eastern Slovakia, the most acid surface water occurs in the area of old mine Smolník, which is closed and submerged for 15 years. The submitted contribution deals with the sulphate-elimination from this locality. Recently, several methods of sulphate-elimination from the mine water are applied. The best-known methods are biological, physical-chemical and chemical precipitation. The method described in this contribution consists of chemical precipitation by sodium aluminate and calcium hydrate. Under application of this method very interesting results were obtained. The amount of SO42- anions decreased to almost zero-value, using optimal doses of the chemical reagents.

Salt marsh stability modelled in relation to sea level rise

DEFF Research Database (Denmark)

Bartholdy, Jesper; Bartholdy, Anders; Kroon, Aart

2010-01-01

thickness. Autocompaction was incorporated in the model, and shown to play a major role for the translation of accretion rates measured as length per unit time to accumulation rates measured as mass per area per unit time. This is important, even for shallow salt marsh deposits for which it is demonstrated...... that mass depth down core can be directly related to the bulk dry density of the surface layer by means of a logarithmic function. The results allow for an evaluation of the use of marker horizons in the topmost layers and show that it is important to know the level of the marker in relation to the salt...... marsh base. In general, deeper located markers will indicate successively smaller accretion rates with the same sediment input. Thus, stability analysis made on the basis of newly established marker horizons will be biased and indicate salt marsh stabilities far above the correct level. Running...

The Metal And Sulphate Removal From Mine Drainage Waters By Biological-Chemical Ways

Directory of Open Access Journals (Sweden)

Jenčárová Jana

2015-06-01

Full Text Available Mine drainage waters are often characterized by high concentrations of sulphates and metals as a consequence of the mining industry of sulphide minerals. The aims of this work are to prove some biological-chemical processes utilization for the mine drainage water treatment. The studied principles of contamination elimination from these waters include sulphate reduction and metal bioprecipitation by the application of sulphate-reducing bacteria (SRB. Other studied process was metal sorption by prepared biogenic sorbent. Mine drainage waters from Slovak localities Banská Štiavnica and Smolník were used to the pollution removal examination. In Banská Štiavnica water, sulphates decreased below the legislative limit. The elimination of zinc by sorption experiments achieved 84 % and 65 %, respectively.

High salt meals in staff canteens of salt policy makers: observational study

NARCIS (Netherlands)

Brewster, L.M.; Berentzen, C.A.; van Montfrans, G.A.

2011-01-01

To assess the salt content of hot meals served at the institutions of salt policy makers in the Netherlands. Observational study. 18 canteens at the Department of Health, the Health Council, the Food and Consumer Product Safety Authority, university hospitals, and affiliated non-university

Spatially resolved micro-Raman observation on the phase separation of effloresced sea salt droplets.

Science.gov (United States)

Xiao, Han-Shuang; Dong, Jin-Ling; Wang, Liang-Yu; Zhao, Li-Jun; Wang, Feng; Zhang, Yun-Hong

2008-12-01

We report on the investigation of the phase separation of individual seawater droplets in the efflorescence processes with the spatially resolved Raman system. Upon decreasing the relative humidity (RH), CaSO4.0.5H2O separated out foremost fromthe droplet atan unexpectedly high RH of approcimately 90%. Occasionally, CaSO4.2H2O substituted for CaSO4.O.5H2O crystallizing first at approximately 78% RH. Relatively large NaCI solids followed to crystallize at approximately 55% RH and led to the great loss of the solution. Then, the KMgCl3.6H2O crystallites separated out from the residual solutions, adjacentto NaCl at approximately 44% RH. Moreover, a shell structure of dried sea salt particle was found to form at low RHs, with the NaCl crystals in the core and minor supersaturated solutions covered with MgSO4 gel coating on the surface. Ultimately, the shielded solution partly effloresced into MgSO4 hydrates at very dry state (<5% RH).

Volcanic lake systems as terrestrial analogue for sulphate-rich terrains on Mars

NARCIS (Netherlands)

Rodríguez, A.

2016-01-01

Remote-sensing observations and rover missions have documented the abundant presence of sulphate-rich mineral associations on the surface of Mars. Together with widespread occurrences of silica and frequent enrichments of chlorine and bromine in soils and rocks, the sulphate associations are

Leaching due to hygroscopic water uptake in cemented waste containing soluble salts

DEFF Research Database (Denmark)

Brodersen, K.

1992-01-01

conditions, condensation of water vapour will result in generation of a certain amount of liquid in the form of a strong salt solution. The volume of liquid may well exceed the storage capacity of the pore system in the cemented material and in the release of a limited amount of free contaminated solution......Considerable amounts of easily soluble salts such as sodium nitrate, sulphate, or carbonate are introduced into certain types of cemented waste. When such materials are stored in atmospheres with high relative humidity or disposed or by shallow land burial under unsaturated, but still humid....... A model of the quantitative aspects for the equilibrium situation is presented. Experiments with hygroscopic water uptake support the model and give indications about the rate of the process. The release mechanism is only thought to be important for radionuclides which are not fixed in a low...

New England salt marsh recovery: opportunistic colonization of an invasive species and its non-consumptive effects.

Directory of Open Access Journals (Sweden)

Tyler C Coverdale

Full Text Available Predator depletion on Cape Cod (USA has released the herbivorous crab Sesarmareticulatum from predator control leading to the loss of cordgrass from salt marsh creek banks. After more than three decades of die-off, cordgrass is recovering at heavily damaged sites coincident with the invasion of green crabs (Carcinusmaenas into intertidal Sesarma burrows. We hypothesized that Carcinus is dependent on Sesarma burrows for refuge from physical and biotic stress in the salt marsh intertidal and reduces Sesarma functional density and herbivory through consumptive and non-consumptive effects, mediated by both visual and olfactory cues. Our results reveal that in the intertidal zone of New England salt marshes, Carcinus are burrow dependent, Carcinus reduce Sesarma functional density and herbivory in die-off areas and Sesarma exhibit a generic avoidance response to large, predatory crustaceans. These results support recent suggestions that invasive Carcinus are playing a role in the recovery of New England salt marshes and assertions that invasive species can play positive roles outside of their native ranges.

High Spatial resolution remote sensing for salt marsh change detection on Fire Island National Seashore

Science.gov (United States)

Campbell, A.; Wang, Y.

2017-12-01

Salt marshes are under increasing pressure due to anthropogenic stressors including sea level rise, nutrient enrichment, herbivory and disturbances. Salt marsh losses risk the important ecosystem services they provide including biodiversity, water filtration, wave attenuation, and carbon sequestration. This study determines salt marsh change on Fire Island National Seashore, a barrier island along the south shore of Long Island, New York. Object-based image analysis was used to classifying Worldview-2, high resolution satellite, and topobathymetric LiDAR. The site was impacted by Hurricane Sandy in October of 2012 causing a breach in the Barrier Island and extensive overwash. In situ training data from vegetation plots were used to train the Random Forest classifier. The object-based Worldview-2 classification achieved an overall classification accuracy of 92.75. Salt marsh change for the study site was determined by comparing the 2015 classification with a 1997 classification. The study found a shift from high marsh to low marsh and a reduction in Phragmites on Fire Island. Vegetation losses were observed along the edge of the marsh and in the marsh interior. The analysis agreed with many of the trends found throughout the region including the reduction of high marsh and decline of salt marsh. The reduction in Phragmites could be due to the species shrinking niche between rising seas and dune vegetation on barrier islands. The complex management issues facing salt marsh across the United States including sea level rise and eutrophication necessitate very high resolution classification and change detection of salt marsh to inform management decisions such as restoration, salt marsh migration, and nutrient inputs.

Salt balance, fresh water residence time and budget for non ...

African Journals Online (AJOL)

Water and salt budgets suggest that in order to balance the inflow and outflow of water at Makoba bay, there is net flux of water from the bay to the open ocean during wet season. Residual salt fluxes between the bay and the open ocean indicate advective salt export. Exchange of water between the bay with the open ocean ...

Biogenic, anthropogenic and sea salt sulfate size-segregated aerosols in the Arctic summer

Directory of Open Access Journals (Sweden)

R. Ghahremaninezhad

2016-04-01

Full Text Available Size-segregated aerosol sulfate concentrations were measured on board the Canadian Coast Guard Ship (CCGS Amundsen in the Arctic during July 2014. The objective of this study was to utilize the isotopic composition of sulfate to address the contribution of anthropogenic and biogenic sources of aerosols to the growth of the different aerosol size fractions in the Arctic atmosphere. Non-sea-salt sulfate is divided into biogenic and anthropogenic sulfate using stable isotope apportionment techniques. A considerable amount of the average sulfate concentration in the fine aerosols with a diameter  <  0.49 µm was from biogenic sources (>  63 %, which is higher than in previous Arctic studies measuring above the ocean during fall (<  15 % (Rempillo et al., 2011 and total aerosol sulfate at higher latitudes at Alert in summer (>  30 % (Norman et al., 1999. The anthropogenic sulfate concentration was less than that of biogenic sulfate, with potential sources being long-range transport and, more locally, the Amundsen's emissions. Despite attempts to minimize the influence of ship stack emissions, evidence from larger-sized particles demonstrates a contribution from local pollution. A comparison of δ34S values for SO2 and fine aerosols was used to show that gas-to-particle conversion likely occurred during most sampling periods. δ34S values for SO2 and fine aerosols were similar, suggesting the same source for SO2 and aerosol sulfate, except for two samples with a relatively high anthropogenic fraction in particles  <  0.49 µm in diameter (15–17 and 17–19 July. The high biogenic fraction of sulfate fine aerosol and similar isotope ratio values of these particles and SO2 emphasize the role of marine organisms (e.g., phytoplankton, algae, bacteria in the formation of fine particles above the Arctic Ocean during the productive summer months.

Salton Sea Geothermal Field, California, as a near-field natural analog of a radioactive waste repository in salt

International Nuclear Information System (INIS)

Elders, W.A.; Cohen, L.H.

1983-11-01

Since high concentrations of radionuclides and high temperatures are not normally encountered in salt domes or beds, finding an exact geologic analog of expected near-field conditions in a mined nuclear waste repository in salt will be difficult. The Salton Sea Geothermal Field, however, provides an opportunity to investigate the migration and retardation of naturally occurring U, Th, Ra, Cs, Sr and other elements in hot brines which have been moving through clay-rich sedimentary rocks for up to 100,000 years. The more than thirty deep wells drilled in this field to produce steam for electrical generation penetrate sedimentary rocks containing concentrated brines where temperatures reach 365 0 C at only 2 km depth. The brines are primarily Na, K, Ca chlorides with up to 25% of total dissolved solids; they also contain high concentrations of metals such as Fe, Mn, Li, Zn, and Pb. This report describes the geology, geophysics and geochemistry of this system as a prelude to a study of the mobility of naturally occurring radionuclides and radionuclide analogs within it. The aim of this study is to provide data to assist in validating quantitative models of repository behavior and to use in designing and evaluating waste packages and engineered barriers. 128 references, 33 figures, 13 tables

Salton Sea Geothermal Field, California, as a near-field natural analog of a radioactive waste repository in salt

Energy Technology Data Exchange (ETDEWEB)

Elders, W.A.; Cohen, L.H.

1983-11-01

Since high concentrations of radionuclides and high temperatures are not normally encountered in salt domes or beds, finding an exact geologic analog of expected near-field conditions in a mined nuclear waste repository in salt will be difficult. The Salton Sea Geothermal Field, however, provides an opportunity to investigate the migration and retardation of naturally occurring U, Th, Ra, Cs, Sr and other elements in hot brines which have been moving through clay-rich sedimentary rocks for up to 100,000 years. The more than thirty deep wells drilled in this field to produce steam for electrical generation penetrate sedimentary rocks containing concentrated brines where temperatures reach 365/sup 0/C at only 2 km depth. The brines are primarily Na, K, Ca chlorides with up to 25% of total dissolved solids; they also contain high concentrations of metals such as Fe, Mn, Li, Zn, and Pb. This report describes the geology, geophysics and geochemistry of this system as a prelude to a study of the mobility of naturally occurring radionuclides and radionuclide analogs within it. The aim of this study is to provide data to assist in validating quantitative models of repository behavior and to use in designing and evaluating waste packages and engineered barriers. 128 references, 33 figures, 13 tables.

Bone mineral response to ammonium sulphate offered as a lick supplement in beef calves

Directory of Open Access Journals (Sweden)

L.E. Motsei

2006-06-01

Full Text Available Sixteen Bonsmara calves (4 males, 12 females between 10 and 18 months of age were blocked according to age and sex and randomly assigned to 2 groups. They were offered licks containing bone meal and salt (50:50 ratio (control and bone meal and ammonium sulphate (NH4SO4 at 1.25, 2.5, 5, 10, 15, and 18 % (treatment to evaluate the effects of dietary anions on bone phosphate (P concentration. Bone P concentration was significantly (P<0.05 higher in the NH4SO4 group compared with the control group, indicating that NH4SO4 was able to increase the P content of bone at each of the 6 concentrations used in the lick relative to the control animals, thereby improving the P status of the animals. Ammonium sulphate at 15% and 18% in the lick also significantly (P <0.05 increased bone P compared with the lower concentrations of NH4SO4. Bone calcium (Ca fluctuated as a result of the acidogenic lick. There was absorption of Ca when P was being resorbed and resorption of Ca when P was being absorbed into and out of bone. Bone Ca:P ratio ranged from 3.2 to 6.4 among the control group and 1.6 to 4.3 among the treatment group. Animals receiving the acidogenic lick had a higher percentage ash compared to the control group for most of the experimental period. Bone magnesium (Mg fluctuated in response to the acidogenic lick, and it was difficult to show a relationship between bone Mg and Ca or P. The overall mean cortical bone thickness was significantly (P < 0.05 greater in treatment (1.60 mm compared with control (1.43 mm calves and this was also true at sampling periods 2, 4, 5 and 6. Bone thickness followed bone P and not bone Ca. Results from this research indicate that the addition of ammonium sulphate to a lick had a beneficial effect in improving the P status by increasing bone P and improving the mineral status of bone by increasing the thickness of cortical bone and percentage ash.

Thin- and thick-skinned salt tectonics in the Netherlands: a quantitative approach

NARCIS (Netherlands)

Veen, J.H. ten; Gessel, S.F. van; Dulk, M. den

2012-01-01

The Zechstein salt in the Dutch part of the North Sea Basin played a key role in the generation of successful petroleum plays. This is not only because of its sealing capacity, but also because the salt occurs in structures that provide lateral and vertical traps. The structural styles of areas with

Numerical research on natural convection in molten salt reactor with non-uniformly distributed volumetric heat generation

International Nuclear Information System (INIS)

Qian Libo; Qiu Suizheng; Zhang Dalin; Su Guanghui; Tian Wenxi

2010-01-01

Molten salt reactor is one of the six Generation IV systems capable of breeding and transmutation of actinides and long-lived fission products, which uses the liquid molten salt as the fuel solvent, coolant and heat generation simultaneously. The present work presents a numerical investigation on natural convection with non-uniform heat generation through which the heat generated by the fluid fuel is removed out of the core region when the reactor is under post-accident condition or zero-power condition. The two-group neutron diffusion equation is applied to calculated neutron flux distribution, which leads to non-uniform heat generation. The SIMPLER algorithm is used to calculate natural convective heat transfer rate with isothermal or adiabatic rigid walls. These two models are coupled through the temperature field and heat sources. The peculiarities of natural convection with non-uniform heat generation are investigated in a range of Ra numbers (10 3 ∼ 10 7 ) for the laminar regime of fluid motion. In addition, the numerical results are also compared with those containing uniform heat generation.

Mechanism of growth, composition and structure of oxide films formed on ferrous alloys in molten salt electrolytes - a review

International Nuclear Information System (INIS)

Tzvetkoff, Tz.; Kolchakov, J.

2004-01-01

The growth kinetics, chemical composition and structure of scales formed during corrosion of Fe and its alloys in molten salts are reviewed. Special attention is paid to the effect of the composition of the molten salt mixture and the gas atmosphere on the stability and protective ability of corrosion layers. First, the thermodynamical background of the corrosion and oxidation of Fe-base engineering materials in molten salt media is briefly commented. A concise review of the growth kinetics of passivating oxide films is also presented. These two introductory chapters serve as a guide for the extensive survey of the growth mechanism, nature and properties of oxide and related scales on ferrous alloys in a range of molten electrolytes - chlorides, nitrates, sulphates, carbonates, hydroxides and mixtures thereof in gas atmospheres containing O 2 , CO 2 , SO 2 , SO 3 and HCl

Use of GSR particle analysis program on an analytical SEM to identify sources of emission of airborne particles

International Nuclear Information System (INIS)

Chan, Y.C.; Trumper, J.; Bostrom, T.

2002-01-01

Full text: High concentrations of airborne particles, in particular PM 10 (particulate matter 10 , but has been little used in Australia for airborne particulates. Two sets of 15 mm PM 10 samples were collected in March and April 2000 from two sites in Brisbane, one within a suburb and one next to an arterial road. The particles were collected directly onto double-sided carbon tapes with a cascade impactor attached to a high-volume PM 10 sampler. The carbon tapes were analysed in a JEOL 840 SEM equipped with a Be-window energy-dispersive X-ray detector and Moran Scientific microanalysis system. An automated Gun Shot Residue (GSR) program was used together with backscattered electron imaging to characterise and analyse individual particulates. About 6,000 particles in total were analysed for each set of impactor samples. Due to limitations of useful pixel size, only particles larger than about 0.5 μm could be analysed. The size, shape and estimated elemental composition (from Na to Pb) of the particles were subjected to non-hierarchical cluster analysis and the characteristics of the clusters were related to their possible sources of emission. Both samples resulted in similar particle clusters. The particles could be classified into three main categories non-spherical (58% of the total number of analysed particles, shape factor >1 1), spherical (15%) and 'carbonaceous' (27%, ie with unexplained % of elemental mass >75%). Non-spherical particles were mainly sea salt and soil particles, and a small amount of iron, lead and mineral dust. The spherical particles were mainly sea salt particles and flyash, and a small amount of iron, lead and secondary sulphate dust. The carbonaceous particles included carbon material mixed with secondary aerosols, roadside dust, sea salt or industrial dust. The arterial road sample also contained more roadside dust and less secondary aerosols than the suburb sample. Current limitations with this method are the minimum particle size

Abiotic nitrate and sulphate reduction by hydrogen: a comparative experimental study

International Nuclear Information System (INIS)

Truche, L.; Berger, G.; Albrecht, A.; Giffaut, E.

2010-01-01

Document available in extended abstract form only. The bituminous waste which is part of the intermediate level, long-lived waste (MAVL) is characterised, amongst others, by the coexistence of nitrates, sulphates, organic matter, native metals and hydrogen gas in the waste mixture and package. It can be considered as the most complex example that will be used to discuss redox reactions occurring in such waste mixtures. The evaluation of the redox conditions requires quantification of the amount of electron acceptors and donors and definition of the kinetics of redox reaction. The objectives of an experimental study to unravel some of these reaction complexities are: - to investigate nature and rate of sulphate and nitrate reduction by hydrogen in the presence of different catalysts (stainless steel, hastelloy, magnetite and argillite); - to compare sulphate and nitrate as electron acceptors; - to provide a mechanistic model of these reactions. It is well known that reduction of sulphate and nitrate requires high activation energies, usually supplied either by thermal processes or via bacterial and surface catalysis, of which the latter has been investigated in this study. Preliminary experiments performed at 150 deg. C and under H 2 pressure show that sulphate reduction is enhanced in the presence of magnetite, but essentially under the restricted condition of low sulphate concentration and at a pH below the Point of Zero Charge of magnetite. This suggests that sorption of sulphate contributes to the catalysed reaction (at low pH) but provided that the magnetite surface sites are not saturated with respect to aqueous sulphate (low concentration). On the contrary, nitrate reduction is observed whatever the pH and the nitrate concentration in the presence of both magnetite and hastelloy C276 (Ni, Cr, Mo, W, Fe alloy). The effect of temperature on the rate of nitrate reduction (500 ppm KNO 3 solution) is shown by comparing three different experiments conducted in

Salt Marshes as Potential Indicatore of Global Climate Change

DEFF Research Database (Denmark)

Kim, Daehyun; Cairens, David; Jung, S.H.

2011-01-01

Coastal scientists postulate that salt marshes are significantly affected by dynamics of global climate. However, few studies have explicitly proposed a perspective that regards salt marshes as potential indicators of climate change. This review article evaluates the possibility of salt marshes...... as indicators of global climate change, focusing upon three major aspects: sedimentary, vegetation, and biogeochemical dynamics. The previous literature concerned with these aspects commonly argues that the primary impact of climate change on salt marshes occurs via sea-level variations, because hydrologic...... fluctuations regulate the frequency, duration, and depth of over-marsh flooding events. Sedimentary, floristic, and biogeochemical dynamics prove to be significantly influenced by sealevel changes regardless of climate zones, and hence, undoubtedly possess a potential for indicating climate signatures. However...

Thermodynamic study of aqueous solutions of polyelectrolytes of low and medium charge density without added salt by direct measurement of osmotic pressure

Energy Technology Data Exchange (ETDEWEB)

Nagy, Miklos, E-mail: miklosnagy@chem.elte.h [Institute of Chemistry, Department of Physical Chemistry, Laboratory for Colloid and Supermolecular Structures, L. Eoetvoes University, P.O. Box 32 H-1518 Budapest 112 (Hungary)

2010-03-15

A special block osmometer has been constructed and applied to a systematic study of poly (vinyl alcohol and vinyl sulphate ester) (PVS) sodium salts in dilute and moderately concentrated salt free aqueous solutions. In order to avoid surely ionic contamination all parts of the equipment that can contact with the polyelectrolyte solutions were made of different kinds of plastics and glass. The pressure range spans from (50 to 1.3 . 10{sup 5}) Pa. The measuring system was found to be appropriate for determination of the molar mass of water soluble polymers, too. Above a certain analytical density of dissociable groups (ADDG) an ion size dependent transition was observed on the reduced osmotic pressure vs. concentration curves. The analysis of the osmotic pressure data has clearly revealed that the dependence of the degree of dissociation on ADDG calculated at zero polyelectrolyte concentration contradicts to 'ion condensation' theory. With increasing polyelectrolyte concentration the degree of dissociation decreased rather steeply but at very low concentrations sharp maximums appeared due either to the change in conformation of these charged macromolecules, or formation of dynamic clusters induced by salting out of neutral parts of the macromolecules by the ionized groups. The applicability of the scaling concept as well as the many possible ways of characterization of non-ideality of polyelectrolyte solutions will be discussed in detail.

Passivation behavior of Type 304 stainless steel in a non-aqueous alkyl carbonate solution containing LiPF6 salt

International Nuclear Information System (INIS)

Myung, Seung-Taek; Sasaki, Yusuke; Saito, Takamitsu; Sun, Yang-Kook; Yashiro, Hitoshi

2009-01-01

Passivation behavior of type 304 stainless steel in a non-aqueous alkyl carbonate solution containing LiPF 6 salt was studied using electrochemical polarization, X-ray photoelectron spectroscopy (XPS) and time of flight-secondary ion mass spectroscopy (ToF-SIMS). Cathodic polarization to 0 V vs. Li/Li + resulted in most but not complete reduction of the air-formed film from oxides to metal on the stainless steel, as confirmed by XPS. For complete elimination of the air-formed film, the surface of the stainless steel was scratched under anodic polarization conditions. At 3 V vs. Li/Li + where an anodic current peak appeared, only an indistinct layer was recognized on the newly scratched surface, according to ToF-SIMS analysis. Above 4 V vs. Li/Li + , substantial passive films were formed, which were composed of oxides and fluorides of iron and chromium. The origin of oxide was due to water contained in the non-aqueous alkyl carbonate solution, and that of fluorides were the result of the decomposition of electrolytic salt, LiPF 6 , especially at higher potential. The resultant passive films were stable in the non-aqueous alkyl carbonate solution containing LiPF 6 salt.

Structure and rheological characteristics of fucoidan from sea cucumber Apostichopus japonicus.

Science.gov (United States)

Yu, Long; Xue, Changhu; Chang, Yaoguang; Hu, Yanfang; Xu, Xiaoqi; Ge, Lei; Liu, Guanchen

2015-08-01

Sea cucumber is a traditional health food consumed in East Asia. In this study, fucoidan from sea cucumber Apostichopus japonicus (Aj-FUC) was isolated, and its structure and rheological characteristics were elucidated for the first time. Aj-FUC was a branched polysaccharide mainly composed of a novel repeating unit [α-L-Fucp2(OSO3(-))-1 → 3,(α-L-Fucp-1 → 4-α-L-Fucp-1 →)4-α-L-Fucp2(OSO3(-))-1 → 3-α-L-Fucp2(OSO3(-))], clarified by using a combination of infrared spectroscopy, methylation analysis, enzymatic degradation and nuclear magnetic resonance. In steady shear measurement, Aj-FUC manifested a non-Newtonian shear-thinning behaviour at low shear rate (1-100 S(-1)) while exhibiting a non-Newtonian shear-thickening behaviour at high shear rate (100-1000 S(-1)); salts had limited impact on its flow curve. Comparative study on viscosity and rheological behaviour of Aj-FUC and a linear fucoidan extracted from sea cucumber Acaudina molpadioides suggested that the presence of branch structure might significantly influence the rheological characteristics of fucoidan. Copyright © 2015 Elsevier Ltd. All rights reserved.

The distribution of soluble radionuclide-relevant trace elements between salt minerals and saline solutions; Die Verteilung loeslicher Radionuklid-relevanter Spurenelemente zwischen Salzmineralen und salinaren Loesungen

Energy Technology Data Exchange (ETDEWEB)

Voss, Ina

2015-07-16

The research platform ENTRIA (Disposal options for radioactive residues Interdisciplinary analyses and development of evaluation principles) includes the sub-project ''Final disposal in deep geological formations without any arrangements for retrieval''. This approach considers rock salt (beside clay and granite) as host rock formation for disposal of heat-producing long-live waste. Most rock salt formations contain Mg-rich brines derived from highly evolved sea water evaporation processes now included in the rock salt mass. If such brines get access to metal-canister corrosion will allow release of soluble nuclides to the brine. In this scenario, it cannot be excluded that contaminated brines leave the deep seated disposal area and move along geological or technical migration pathways towards the rock salt/cap rock contact. The temperature of the brine will drop from near 80 C to 25 or 30 C. The deceasing temperature of the brine causes precipitation of magnesian chloride and sulfate phase in equilibrium with the brine. In order to understand the salt precipitation and the retention mechanism of dissolved trace elements experiments have been set up which allow formation of sylvite, carnallite, kainite, and hydrous Mg-sulphates under controlled conditions. The retention capacity of crystallizing salt minerals based occurring in magnesian brine solutions at decreasing temperature within a salt dome is best measured as the distribution coefficient D. This concept assumes incorporation of trace elements into the lattice of salt minerals. The distribution coefficients of the trace elements, Rb, Cs, Co, Ni, Zn, Li and B between sylvite, carnallite, kainite, and MgSO{sub 4} phases have been determined at experimental temperatures of 25, 35, 55 and 83 C. The results clearly indicate the following range of distribution coefficients (D): Sylvite D > 1 Rb and Br, D < 1 Co, Ni, Zn, Li and B, Carnallite D > 1 Rb and Cs, D < 1 Co, Ni, Zn, Li and B, Kainite D

Salton Sea geothermal field as a natural analog for the near-field in a salt high-level nuclear waste repository

International Nuclear Information System (INIS)

Elders, W.A.; Moody, J.B.; Battelle Memorial Inst., Columbus, OH)

1984-01-01

The Salton Sea Geothermal Field (SSGF), on the delta of the Colorado River in southern California, is being studied as a natural analog for the near-field environment of proposed nuclear waste repositories in salt. A combination of mineralogical and geochemical methods is being employed to develop a three-dimenisonal picture of temperature, salinity, lithology, mineralogy, and chemistry of reactions between the reservoir rocks and the hot brines. Our aim is to obtain quantitative data on mineral stabilities and on mobilities of the naturally occurring radionuclides of concern in Commercial High-Level Waste (CHLW). These data will be used to validate the EQ3/6 geochemical code under development to model the salt near-field repository behavior. Maximum temperatures encountered in wells in the SSGF equal or exceed peak temperatures expected in a salt repository. Brines produced from these wells have major element chemistry similar to brines from candidate salt sites. Relative to the rocks, these brines are enriched in Na, Mn, Sr, Ra, and Po, depleted in Ba, Si, Mg, Ti, and Al, and strongly depleted in U and Th. However, the unaltered rocks contain only about 2 to 3 ppm of U and 4 to 12 ppm of Th, largely in detrital epidotes and zircons. Samples of hydrothermally altered rocks from a wide range of temperature and salinity show rather similar uniform low concentrations of these elements, even when authigenic illite, chlorite, ipidote and feldspar are present. These observations suggest that U and Th are relatively immobile in these hot brines. However, Ra, Po, Cs, and Sr are relatively mobile. Work is continuing to document naturally occurring radionuclide partitioning between SSGF minears and brine over a range of temperature, salinity, and lithology. 8 refs., 7 figs., 2 tabs

Sulphate content of the Muntimpa dam water and its impact on water quality

International Nuclear Information System (INIS)

Tembo, F; Shitumbanuma, V; Simukanga, S; Mudenda, G; Chileshe, P; Mulenga, S; Phiri, Y

2004-01-01

This article presents results of a study of the quality of water from Muntimpa Dam, a reservior of waste mine water released from the processing of copper and cobalt ores by Konkola Copper Mines(KCM) Plc in Chingola. The mine water is discharged into the local Muntimpa stream, a possible source of drinking and domestic water for the local population. The purpose of the study was to determine levels of sulphate in the dam and stream water and recommend possible methods of partial sulphate removal to levels below the recommended statutory limits and secondly, to assess the impact of high sulphate levels on water quality. Study methods included the sampling of water from the Muntimpa dam and catchment area. Stream water samples were collected about 5m from the stream banks while water samples from the dam were randomly collected from the near the centre of the dam at a depth of 50cm. Laboratory methods involved the determination of physical and chemical properties of the water using standard analytical techniques. Results of the study indicate that both total (2470mg/l) and available (1965mg/l) sulphate concentrations are higher than the recommended statutory limit for the discharge of sulphates into natural streams of 1500mg/l. From the study it is concluded that water in Muntimpa dam and stream is not suitable for drinking and other domestic use due to the high sulphate levels. From theorectical considerations, it was established that sulphate reduction could be achieved by addition of lime, which however had the consquence of increasing the pH of the water in excess of the recommended Zambian statutory value of nine, and would thus require an additional process to reduce the pH. (author)

Proposal of a integrated system for the complete usage of sea water

International Nuclear Information System (INIS)

Ohya, Haruhiko; Suzuki, Takashi; Nakao, Shin-ichi; Kato, Shigeru; Tsuji, Masamichi; Sugi, Jiro.

1995-01-01

Very severe troubles of scale formation might be expected to occur when recovery of water from sea water increases. The main constituents of the scale are CaCO 3 , Mg(OH) 2 , CaSO 4 and so on, all of which are salts of alkaline earth metals. Therefore, if a key technology is developed by which the main constituents of the scale, alkaline earth metal ions mentioned above, can be removed and/or separated from sea water, the recovery of desalted water from raw sea water by high-pressure reverse osmosis (HPRO) can be increased up to 75-80%, the solubility limit of the remaining scale components. Then it will be possible to make use of all valuable materials existing in sea water, by an integrated system which combines conventional recovery technologies with a set of the proposed technologies such as HPRO, alkaline earth metal ions removal process, inorganic ion-exchangers for recovery of trace elements and so on. Furthermore, almost complete usage of sea water may be accomplished by irrigation of the brackish water by-product for salt-resistant plants such as mangrove, salt bush and, if possible, gene-recombinated plants. (author)

Grass-cellulose as energy source for biological sulphate removal from acid mine effluents

CSIR Research Space (South Africa)

Greben, HA

2008-11-01

Full Text Available The biological sulphate removal technology requires carbon and energy sources to reduce sulphate to sulphide. Plant biomass, e.g. grass, is a sustainable source of energy when cellulose is utilised during anaerobic degradation, producing volatile...

Two planets: Earth and Mars - One salt model: The Hydrothermal SCRIW-Model

Science.gov (United States)

Hovland, M. T.; Rueslaatten, H.; Johnsen, H. K.; Indreiten, T.

2011-12-01

One of the common characteristics of planets Earth and Mars is that both host water (H2O) and large accumulations of salt. Whereas Earth's surface-environment can be regarded as 'water-friendly' and 'salt hostile', the reverse can be said for the surface of Mars. This is because liquid water is stable on Earth, and the atmosphere transports humidity around the globe, whereas on planet Mars, liquid water is unstable, rendering the atmosphere dry and, therefore, 'salt-friendly'. The riddle as to how the salt accumulated in various locations on those two planets is one of long-lasting and great debate. The salt accumulations on Earth are traditionally termed 'evaporites', meaning that they formed by the evaporation of large masses of seawater. How the accumulations on Mars formed is much harder to explain, with a similar model, as surface water, representing a large ocean only existed briefly. Although water molecules and OH-groups may exist in abundance in bound form (crystal water, adsorbed water, etc.), the only place where free water is expected to be stable on Mars is within underground faults, fractures, and crevices. Here it likely occurs as brine or in the form of ice. Based on these conditions, a key to understanding the accumulation of large deposits of salt on both planets is linked to how brines behave in the subsurface when pressurized and heated beyond their supercritical point. At depths greater than about 3 km (i.e., a pressure, P>300 bars) water will no longer boil in a steam phase. Rather, it becomes supercritical and will form a supercritical water 'vapor' (SCRIW) with a specific gravity of typically 0.3 g/cm3. An important characteristic of SCRIW is its inability to dissolve the common sea salts. The salt dissolved in the brines will therefore precipitate as solid particles when brines (seawater on the Earth) move into the supercritical P&T-domain (above 400 C and 300 bars). Numerical modeling of a hydrothermal system in the Atlantis II Deep of the

Development of a glass matrix for vitrification of sulphate bearing high level radioactive liquid waste

International Nuclear Information System (INIS)

Kaushik, C.P.; Mishra, R.K.; Thorat, Vidya; Ramchandran, M.; Amar Kumar; Ozarde, P.D.; Raj, Kanwar; Das, D.

2004-07-01

High level radioactive liquid waste (HLW) is generated during reprocessing of spent nuclear fuel. In the earlier reprocessing flow sheet ferrous sulphamate has been used for valancy adjustment of Pu from IV to III for effective separation. This has resulted in generation of HLW containing significance amount of sulphate. Internationally borosilicate glass matrix has been adopted for vitrification of HLW. The first Indian vitrification facility at Waste Immobilislition Plant (WIP), Tarapur a five component borosilicate matrix (SiO 2 :B 2 O 3 :Na 2 O : MnO : TiO 2 ) has been used for vitrification of waste. However at Trombay HLW contain significant amount of sulphate which is not compatible with standard borosilicate formulation. Extensive R and D efforts were made to develop a glass formulation which can accommodate sulphate and other constituents of HLW e.g., U, Al, Ca, etc. This report deals with development work of a glass formulations for immobilization of sulphate bearing waste. Different glass formulations were studied to evaluate the compatibility with respect to sulphate and other constituents as mentioned above. This includes sodium, lead and barium borosilicate glass matrices. Problems encountered in different glass matrices for containment of sulphate have also been addressed. A glass formulation based on barium borosilicate was found to be effective and compatible for sulphate bearing high level waste. (author)

Behaviour of horses and cattle at two stocking densities in a coastal salt marsh

NARCIS (Netherlands)

Nolte, S.; Weyde, van der C.; Esselink, P.; Smit, C.; Wieren, van S.E.; Bakker, J.P.

2017-01-01

Livestock grazing has been practiced in salt marshes in the Wadden Sea area since 600 B.C. Currently livestock grazing is also applied for conservation management. However, effects of such grazing management on salt marshes are likely to vary depending on the species of livestock and stocking

Behaviour of horses and cattle at two stocking densities in a coastal salt marsh

NARCIS (Netherlands)

Nolte, S.; Van der Weyde, C; Esselink, Peter; Smit, C.; Van Wieren, S.E.; Bakker, Jan P.

Livestock grazing has been practiced in salt marshes in the Wadden Sea area since 600 B.C. Currently livestock grazing is also applied for conservation management. However, effects of such grazing management on salt marshes are likely to vary depending on the species of livestock and stocking

Effect of salt solutions on the radiosensitivity of mammalian cells as a function of the state of adhesion and the water structure

Energy Technology Data Exchange (ETDEWEB)

Moggach, P G; Lepock, J R; Kruuv, J [Waterloo Univ., Ontario (Canada). Dept. of Physics

1979-11-01

The radiation isodose survival curve of attached Chinese hamster (V79) cells, subjected to a wide concentration range of salt or sucrose solutions, was characterized by two maxima separated by a minimum. Cells were radioprotected at the maxima (high and low hypertonic salt concentrations) while they were radiosensitized at the minimum (intermediate hypertonic salt concentrations). Both cations and anions could alter the cellular radiosensitivity above and beyond the (osmotic) effect observed for cells treated with sucrose solutions. However, the basic curve shape, except in the case of sulphate salts, remained the same. When these experiments were repeated with single cells in suspension, the isodose survival curve was quite different in that high salt concentrations did not protect cells in suspension unlike the case with attached cells. The curve shape was also altered in that the second maximum was absent with many salt solutions. When multicellular spheroids were used for these experiments, the data resembled those for single cell suspensions rather than for attached cells. The radiation survival data for cells in suspension in salt solutions correlated with water proton spin lattice relaxation time (T/sub 1/) and, in hypo- and iso-tonic solutions, with cell volume.

Analysis of chromium and sulphate origins in construction recycled materials based on leaching test results.

Science.gov (United States)

Del Rey, I; Ayuso, J; Galvín, A P; Jiménez, J R; López, M; García-Garrido, M L

2015-12-01

Twenty samples of recycled aggregates from construction and demolition waste (CDW) with different compositions collected at six recycling plants in the Andalusia region (south of Spain) were characterised according to the Landfill Directive criteria. Chromium and sulphate were identified as the most critical compounds in the leachates. To detect the sources of these two pollutant constituents in recycled aggregate, environmental assessments were performed on eight construction materials (five unused ceramic materials, two old crushed concretes and one new mortar manufactured in the laboratory). The results confirmed that leached sulphate and Cr were mainly released by the ceramic materials (bricks and tiles). To predict the toxicological consequences, the oxidation states of Cr (III) and Cr (VI) were measured in the leachates of recycled aggregates and ceramic materials classified as non-hazardous. The bricks and tiles mainly released total Cr as Cr (III). However, the recycled aggregates classified as non-hazardous according to the Landfill Directive criteria mainly released Cr (VI), which is highly leachable and extremely toxic. The obtained results highlight the need for legislation that distinguishes the oxidative state in which chromium is released into the environment. Leaching level regulations must not be based solely on total Cr, which can lead to inaccurate predictions. Copyright © 2015 Elsevier Ltd. All rights reserved.

Climate change as a confounding factor in reversibility of acidification: RAIN and CLIMEX projects

Directory of Open Access Journals (Sweden)

R. F. Wright

2001-01-01

Full Text Available The RAIN and CLIMEX experiments at Risdalsheia, southernmost Norway, together cover 17 years (1984-2000 of whole-catchment manipulation of acid deposition and climate. A 1200 m2 roof placed over the forest canopy at KIM catchment excluded about 80% of ambient acid deposition; clean rain was sprinkled under the roof. A climate change treatment (3.7°C increase in air temperature and increase in air carbon dioxide concentrations to 560 ppmv was superimposed on the clean rain treatment for four years (1995-1998. Sea-salt inputs and temperature are climate-related factors that influence water chemistry and can confound long-term trends caused by changes in deposition of sulphur and nitrogen. The RAIN and CLIMEX experiments at Risdalsheia provided direct experimental data that allow quantitative assessment of these factors. Run-off chemistry responded rapidly to the decreased acid deposition. Sulphate concentrations decreased by 50% within three years; nitrate and ammonium concentrations decreased to new steady-state levels within the first year. Acid neutralising capacity increased and hydrogen ion and inorganic aluminium decreased. Similar recovery from acidification was also observed at the reference catchment, ROLF, in response to the general 50% reduction in sulphate deposition over southern Norway in the late 1980s and 1990s. Variations in sea-salt deposition caused large variations in run-off chemistry at the reference catchment ROLF and the year-to-year noise in acid neutralising capacity was as large as the overall trend over the period. These variations were absent at KIM catchment because the sea-salt inputs were held constant over the entire 17 years of the clean rain treatment. The climate change experiment at KIM catchment resulted in increased leaching of inorganic nitrogen, probably due to increased mineralisation and nitrification rates in the soils. Keywords: acid deposition, global change, water, soil, catchment, experiment, Norway.

Effect of hurricanes and violent storms on salt marsh

Science.gov (United States)

Leonardi, N.; Ganju, N. K.; Fagherazzi, S.

2016-12-01

Salt marsh losses have been documented worldwide because of land use change, wave erosion, and sea-level rise. It is still unclear how resistant salt marshes are to extreme storms and whether they can survive multiple events without collapsing. Based on a large dataset of salt marsh lateral erosion rates collected around the world, here, we determine the general response of salt marsh boundaries to wave action under normal and extreme weather conditions. As wave energy increases, salt marsh response to wind waves remains linear, and there is not a critical threshold in wave energy above which salt marsh erosion drastically accelerates. We apply our general formulation for salt marsh erosion to historical wave climates at eight salt marsh locations affected by hurricanes in the United States. Based on the analysis of two decades of data, we find that violent storms and hurricanes contribute less than 1% to long-term salt marsh erosion rates. In contrast, moderate storms with a return period of 2.5 mo are those causing the most salt marsh deterioration. Therefore, salt marshes seem more susceptible to variations in mean wave energy rather than changes in the extremes. The intrinsic resistance of salt marshes to violent storms and their predictable erosion rates during moderate events should be taken into account by coastal managers in restoration projects and risk management plans.

Treatment of acid and sulphate-rich effluents in an integrated biological/chemical process

CSIR Research Space (South Africa)

Maree, JP

2004-04-01

Full Text Available .4 g SO4/(l.d). The rate of biological sulphate removal was found to be directly related to the square root of sulphate, COD and VSS concentrations respectively, and inversely proportional to sulphide concentration. The practical value of simultaneous...

Salt effect on sensitized photooxidations. A kinetic approch to environmental decomposition of marine contaminants

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María I. Gutiérrez

1998-09-01

Full Text Available The salt effect on the kinetics of singlet molecular oxygen [O2(1Δg]-mediated photooxidations of sea water contaminants was investigated. Two families of photooxidizable compounds were employed in the study: anthracene derivatives and phenols. The presence of salt (NaCl in H2O and LiCl in MeCN, in both cases in the range 0-0.45 M produces changes in the photooxidation rate. For solvent-polarity-dependent reactions, this behavior can be predicted, by knowing the solvent-polarity dependence of the rate constant for chemical reaction of the substrates with O2(1Δ g in non-saline solutions (kr. For the cases of photooxidations possessing solvent-polarity-independent or scantily-dependent kr values, the photooxidation rates decrease as the salt content in the solution increases, mainly due to a predominance of the physical quenching pathway. In addition, the quantum yield for O2(1 Δg generation (ΦΔ was determined in a series of saline solutions, in the range of 0-0.45 M in water and MeCN solutions, in the presence of NaCl and LiCl respectively. The Δ values are independent, within the experimental error on the salt content.

Sodium Sulphate Effect on Cement Produced with Building Stone Waste

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Emre Sancak

2015-01-01

Full Text Available In this study, the blended cements produced by using the building stone waste were exposed to sulphate solution and the cement properties were examined. Prepared mortar specimens were cured under water for 28 days and then they were exposed to three different proportions of sodium sulphate solution for 125 days. Performances of cements were determined by means of compressive strength and tensile strength tests. The broken parts of some mortar bars were examined with scanning electron microscope (SEM. Besides, they were left under moist atmosphere and their length change was measured and continuously monitored for period of 125 days. In blended cements, solely cements obtained by replacing 10–20% of diatomites gave similar strength values with ordinary Portland cement (CEM I 42.5R at the ages of 7, 28, and 56 days. In all mortar specimens that included either waste andesite (AP or marble powder (MP showed best performance against very severe effective sodium sulphate solutions (13500 mg/L.

Should Magnesium Sulphate Prophylaxis be Used in all Cases of Severe Preeclampsia?

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Sohini Bhattacharya,

2011-01-01

Full Text Available A case control study, undertaken in the department of Obstetrics and Gynecology in a tertiary referral centre, was designed to administer standard dose of magnesium sulphate to 50 randomly selected severely preeclamptic women in labor (Group 1. 48 women who formed the control group did not receive the drug (Group 2. The admission – delivery interval, rate of Cesarean section showed no statistically significant difference. Four patients developed convulsions in Group 1 in contrast to twelve patients in Group 2. Efficacy of magnesium sulphate at preventing eclampsia was calculated as 68%. Mild respiratory depression occurred in two cases and oliguria in eight cases in Group 1. Both the conditions improved on suspending further doses of magnesium sulphate. No patient had post partum haemorrhage in Group 1 although 4% patients had it in Group 2. Neonatal outcome was comparable in both the groups. Hence magnesium sulphate may be regarded as a fairly safe and effective prophylactic agent for eclampsia when used in severe preeclampsia in labor.

Thermal decomposition of hydrotalcite with chromate, molybdate or sulphate in the interlayer

Energy Technology Data Exchange (ETDEWEB)

Frost, Ray L. [Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane Queensland 4001 (Australia)]. E-mail: r.frost@qut.edu.au; Musumeci, Anthony W. [Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane Queensland 4001 (Australia); Bostrom, Thor [Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane Queensland 4001 (Australia); Adebajo, Moses O. [Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane Queensland 4001 (Australia); Weier, Matt L. [Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane Queensland 4001 (Australia); Martens, Wayde [Inorganic Materials Research Program, School of Physical and Chemical Sciences, Queensland University of Technology, GPO Box 2434, Brisbane Queensland 4001 (Australia)

2005-05-15

The thermal decomposition of hydrotalcites with chromate, molybdate and sulphate in the interlayer has been studied using thermogravimetric analysis coupled to a mass spectrometer measuring the gas evolution. X-ray diffraction shows the hydrotalcites have a d(0 0 3) spacing of 7.98 A with very small differences in the d-spacing between the three hydrotalcites. XRD was also used to determine the products of the thermal decomposition. For the sulphate-hydrotalcite decomposition the products were MgO and a spinel MgAl{sub 2}O{sub 4}, for the chromate interlayered hydrotalcite MgO, Cr{sub 2}O{sub 3} and spinel. For the molybdate interlayered hydrotalcite the products were MgO, spinel and MgMoO{sub 4}. EDX analyses enabled the formula of the hydrotalcites to be determined. Two processes are observed in the thermal decomposition namely dehydration and dehydroxylation and for the case of the sulphate interlayered hydrotalcite, a third process is the loss of sulphate. Both the dehydration and dehydroxylation take place in three steps each for each of the hydrotalcites.

Draft Genome of Scalindua rubra, Obtained from the Interface Above the Discovery Deep Brine in the Red Sea, Sheds Light on Potential Salt Adaptation Strategies in Anammox Bacteria.

Science.gov (United States)

Speth, Daan R; Lagkouvardos, Ilias; Wang, Yong; Qian, Pei-Yuan; Dutilh, Bas E; Jetten, Mike S M

2017-07-01

Several recent studies have indicated that members of the phylum Planctomycetes are abundantly present at the brine-seawater interface (BSI) above multiple brine pools in the Red Sea. Planctomycetes include bacteria capable of anaerobic ammonium oxidation (anammox). Here, we investigated the possibility of anammox at BSI sites using metagenomic shotgun sequencing of DNA obtained from the BSI above the Discovery Deep brine pool. Analysis of sequencing reads matching the 16S rRNA and hzsA genes confirmed presence of anammox bacteria of the genus Scalindua. Phylogenetic analysis of the 16S rRNA gene indicated that this Scalindua sp. belongs to a distinct group, separate from the anammox bacteria in the seawater column, that contains mostly sequences retrieved from high-salt environments. Using coverage- and composition-based binning, we extracted and assembled the draft genome of the dominant anammox bacterium. Comparative genomic analysis indicated that this Scalindua species uses compatible solutes for osmoadaptation, in contrast to other marine anammox bacteria that likely use a salt-in strategy. We propose the name Candidatus Scalindua rubra for this novel species, alluding to its discovery in the Red Sea.

The Dead Sea: A model of a desiccating terminal salt lake

International Nuclear Information System (INIS)

Gat, J.R.

2001-01-01

The continuing decline in the water level of the Dead Sea and the commensurate increase in salinity and precipitation of evaporates results in an irreversible evolution of the structure of the sea. The Dead Sea has been switching from its holomictic regime to short meromictic phases of up to 4-year duration, following the particular rainy winters of 1980 and 1992. The massive precipitation of halite in recent years, as well as the re-introduction of the end-brines of the potash plant, is changing the ion composition of the Dead Sea waters. This necessitates the adjustment of the equation-of-state of the brine and the solubility curve of halite. One consequence is that the onset of halite precipitation during the summer occurs earlier and earlier in the annual cycle. New isotopic measurement of δ 37 Cl of the brine and evaporate deposits and of δ 18 O in dissolved oxygen in the water column have yielded new information on geochemical processes in the Dead Sea system. A systematic monitoring of the oxygen and hydrogen isotopes in the Dead Sea waters has, unfortunately, not been continued in recent years and should be encouraged for the future. (author)

Methane emission and consumption at a North Sea gas seep (Tommeliten area

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H. Niemann

2005-01-01

Full Text Available The Tommeliten seepage area is part of the Greater Ekofisk area, which is situated above the Tommeliten Delta salt diapir in the central North Sea (56°29.90' N, 2°59.80' E, Norwegian Block 1/9, 75 m water depth. Here, cracks in a buried marl horizon allow methane to migrate into overlying clay-silt and sandy sediments. Hydroacoustic sediment echosounding showed several venting spots coinciding with the apex of marl domes where methane is released into the water column and potentially to the atmosphere. In the vicinity of the gas seeps, sea floor observations showed small mats of giant sulphide-oxidizing bacteria above patches of black sediments as well as carbonate crusts, which are exposed 10 to 50 cm above seafloor forming small reefs. These Methane-Derived Authigenic Carbonates (MDACs contain 13C-depleted, archaeal lipids indicating previous gas seepage and AOM activity. High amounts of sn2-hydroxyarchaeol relative to archaeol and low abundances of biphytanes in the crusts give evidence that ANaerobic MEthane-oxidising archaea (ANME of the phylogenetic cluster ANME-2 were the potential mediators of Anaerobic Oxidation of Methane (AOM at the time of carbonate formation. Small pieces of MDACs were also found subsurface at about 1.7 m sediment depth, associated with the AOM zone. This zone is characterized by elevated AOM and Sulphate Reduction (SR rates, increased concentrations of 13C-depleted tetraether derived biphytanes, and specific bacterial Fatty Acids (FA. Further biomarker and 16S rDNA based analyses of this horizon give evidence that AOM is mediated by archaea belonging to the ANME-1b group and Sulphate Reducing Bacteria (SRB most likely belonging to the Seep-SRB1 cluster. The zone of active methane consumption was restricted to a distinct horizon of about 20 cm. Concentrations of 13C-depleted lipid biomarkers (e.g. 500 ng g-dw−1 biphythanes, 140 ng g-dw−1 fatty acid ai-C15:0, cell numbers (1.5×108 cells cm−3, AOM and SR

Impacts of climate change and sea level rise to Danish near shore ecosystems

International Nuclear Information System (INIS)

Vestergaard, P.

2001-01-01

Salt marshes and sand dunes are important types of coastal, terrestrial nature, which like other terrestrial ecosystems will be sensible to the future changes in climate, which have been predicted. Due to the processes acting in their morphogenesis and in the development and composition of their ecosystems, they will not least be influenced by sea level rise. Especially a strong impact of a sea level rise of about 50 cm (midrange of the projected global sea level rise) for the next century can be expected on Danish salt marshes, considering their limited vertical range (50-100 cm). (LN)

Combining urbanization and hydrodynamics data to evaluate sea level rise impacts on coastal water resources

Science.gov (United States)

Young, C. R.; Martin, J. B.

2016-02-01

Assessments of the potential for salt water intrusion due to sea level rise require consideration of both coastal hydrodynamic and human activity thresholds. In siliciclastic systems, sea level rise may cause salt intrusion to coastal aquifers at annual or decadal scales, whereas in karst systems salt intrudes at the tidal scalse. In both cases, human activity impacts the freshwater portion of the system by altering the water demand on the aquifer. We combine physicochemical and human activity data to evaluate impact of sea level rise on salt intrusion to siliclastic (Indian River Lagoon, Fl, USA) and karst (Puerto Morelos, Yucatan, Mexico) systems under different sea level rise rate scenarios. Two hydrodynamic modeling scenarios are considered; flux controlled and head controlled. Under a flux controlled system hydraulic head gradients remain constant during sea level rise while under a head controlled system hydraulic graidents diminish, allowing saltwater intrusion. Our model contains three key terms; aquifer recharge, groundwater discharge and hydraulic conductivity. Groundwater discharge and hydraulic conductivity were calculated based on high frequency (karst system) and decadal (siliciclastic system) field measurements. Aquifer recharge is defined as precipitation less evapotranspiration and water demand was evaluated based on urban planning data that provided the regional water demand. Water demand includes agricultural area, toursim, traffic patterns, garbage collection and total population. Water demand was initially estimated using a partial leaset squares regression based on these variables. Our model indicates that water demand depends most on agricultural area, which has changed significantly over the last 30 years. In both systems, additional water demand creates a head controlled scenario, thus increaseing the protential fo salt intrusion with projected sea level rise.

[Effects of salt stress on physiological characters and salt-tolerance of Ulmus pumila in different habitats].

Science.gov (United States)

Liu, Bing-Xiang; Wang, Zhi-Gang; Liang, Hai-Yong; Yang, Min-Sheng

2012-06-01

Taking the Ulmus pumila seedlings from three different habitats (medium-, mild-, and non-saline soils) as test materials, an experiment was conducted to study their salt-tolerance thresholds and physiological characteristic under different levels (0, 2, 4, 6, 8, and 10 g X kg(-1)) of salt stress. With increasing level of the salt stress, the seedlings taken from medium- and mild- saline habitats had a lower increment of leaf membrane permeability, Na+ content, and Na+/K+ but a higher increment of leaf proline, soluble sugar, and K+ contents, and a lower decrement of leaf starch content, net photosynthetic rate, transpiration rate, intercellular CO2 concentration, and stomatic conductance, as compared with the seedlings taken from non-saline habitat. The salt-tolerance thresholds of the seedlings taken from different habitats were in the order of medium- saline habitat (7.76 g X kg(-1)) > mild- saline habitat (7.37 g X kg(-1)) > non-saline habitat (6.95 g X kg(-1)). It was suggested that the U. pumila seedlings in medium- and mild-saline habitats had a stronger adaptability to saline soil environment than the U. pumila seedlings in non-saline soil environment.

Iron deficiency up-regulates iron absorption from ferrous sulphate but not ferric pyrophosphate and consequently food fortification with ferrous sulphate has relatively greater efficacy in iron-deficient individuals.

Science.gov (United States)

Zimmermann, Michael B; Biebinger, Ralf; Egli, Ines; Zeder, Christophe; Hurrell, Richard F

2011-04-01

Fe absorption from water-soluble forms of Fe is inversely proportional to Fe status in humans. Whether this is true for poorly soluble Fe compounds is uncertain. Our objectives were therefore (1) to compare the up-regulation of Fe absorption at low Fe status from ferrous sulphate (FS) and ferric pyrophosphate (FPP) and (2) to compare the efficacy of FS with FPP in a fortification trial to increase body Fe stores in Fe-deficient children v. Fe-sufficient children. Using stable isotopes in test meals in young women (n 49) selected for low and high Fe status, we compared the absorption of FPP with FS. We analysed data from previous efficacy trials in children (n 258) to determine whether Fe status at baseline predicted response to FS v. FPP as salt fortificants. Plasma ferritin was a strong negative predictor of Fe bioavailability from FS (P soluble Fe compounds not only demonstrate better overall absorption and can be used at lower fortification levels, but they also have the added advantage that, because their absorption is up-regulated in Fe deficiency, they innately 'target' Fe-deficient individuals in a population.

Will fluctuations in salt marsh–mangrove dominance alter vulnerability of a subtropical wetland to sea‐level rise?

Science.gov (United States)

Mckee, Karen L.; Vervaeke, William

2018-01-01

To avoid submergence during sea-level rise, coastal wetlands build soil surfaces vertically through accumulation of inorganic sediment and organic matter. At climatic boundaries where mangroves are expanding and replacing salt marsh, wetland capacity to respond to sea-level rise may change. To compare how well mangroves and salt marshes accommodate sea-level rise, we conducted a manipulative field experiment in a subtropical plant community in the subsiding Mississippi River Delta. Experimental plots were established in spatially equivalent positions along creek banks in monospecific stands of Spartina alterniflora (smooth cordgrass) or Avicennia germinans (black mangrove) and in mixed stands containing both species. To examine the effect of disturbance on elevation dynamics, vegetation in half of the plots was subjected to freezing (mangrove) or wrack burial (salt marsh), which caused shoot mortality. Vertical soil development was monitored for 6 years with the surface elevation table-marker horizon system. Comparison of land movement with relative sea-level rise showed that this plant community was experiencing an elevation deficit (i.e., sea level was rising faster than the wetland was building vertically) and was relying on elevation capital (i.e., relative position in the tidal frame) to survive. Although Avicennia plots had more elevation capital, suggesting longer survival, than Spartina or mixed plots, vegetation type had no effect on rates of accretion, vertical movement in root and sub-root zones, or net elevation change. Thus, these salt marsh and mangrove assemblages were accreting sediment and building vertically at equivalent rates. Small-scale disturbance of the plant canopy also had no effect on elevation trajectories—contrary to work in peat-forming wetlands showing elevation responses to changes in plant productivity. The findings indicate that in this deltaic setting with strong physical influences controlling elevation (sediment

Molecular structure of dextran sulphate sodium in aqueous environment

Science.gov (United States)

Yu, Miao; Every, Hayley A.; Jiskoot, Wim; Witkamp, Geert-Jan; Buijs, Wim

2018-03-01

Here we propose a 3D-molecular structural model for dextran sulphate sodium (DSS) in a neutral aqueous environment based on the results of a molecular modelling study. The DSS structure is dominated by the stereochemistry of the 1,6-linked α-glucose units and the presence of two sulphate groups on each α-glucose unit. The structure of DSS can be best described as a helix with various patterns of di-sulphate substitution on the glucose rings. The presence of a side chain does not alter the 3D-structure of the linear main chain much, but affects the overall spatial dimension of the polymer. The simulated polymers have a diameter similar to or in some cases even larger than model α-hemolysin nano-pores for macromolecule transport in many biological processes, indicating a size-limited translocation through such pores. All results of the molecular modelling study are in line with previously reported experimental data. This study establishes the three-dimensional structure of DSS and summarizes the spatial dimension of the polymer, serving as the basis for a better understanding on the molecular level of DSS-involved electrostatic interaction processes with biological components like proteins and cell pores.

Polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and non-ortho-PCBs in eggs of white-tailed sea eagles collected along the Swedish coast in the Baltic Sea.

Science.gov (United States)

Nordlöf, Ulrika; Helander, Björn; Zebühr, Yngve; Bignert, Anders; Asplund, Lillemor

2012-11-01

Concentrations of polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF), and dioxin-like non-ortho-PCBs were measured in white-tailed sea eagle (WTSE) eagle eggs collected along the Swedish coast of the Baltic Sea during the period 1992-2004. The eggs represent two different subpopulations with significantly different nestling brood sizes; the Baltic Proper (BP) with an approximately normal nestling brood size (1.62), and the south Bothnian Sea (sBS) with reduced nestling brood size (1.22) combined with a significantly higher rate of dead eggs. The aim was to investigate if this difference in reproductive outcome was linked to differences in exposure to dioxin-like compounds. Three eggs collected in Greenland in 2000 were included in the study to provide a reference sea eagle population outside of the Baltic Sea region. The concentrations of ∑PCDD, ∑PCDF and ∑non-ortho-PCB in the two subpopulations from the Baltic Sea (BS) region ranged from 0.41-4.1, 1.2-5.3 and 180-970 ng/g lipids, respectively, while in the Greenland population the ranges were 0.11-0.16, 0.22-0.33 and 57-83 ng/g lipid, respectively. 2,3,4,7,8-PCDF was the predominant congener in all areas and accounted for on average 31-49% of the total ∑PCDD/F concentrations. The total toxic equivalents (TEQ) in sBS WTSEs were higher (approximately 39 ng TEQ/g lipid) than reported in eggs for many other birds, and the major contributors to the TEQ in the Baltic Sea were the non-ortho-PCBs. A principal component analysis (PCA) showed a difference in congener pattern between the two Baltic regions that was statistically significant (Hotelling's T(2) test). We found no significant differences in the total TEQ between the two populations (sBS-BP) and thus no evidence was found linking the reproductive impairment in WTSE in sBS to the concentrations of PCDD/Fs or non-ortho-PCBs in the eggs. Copyright © 2012 Elsevier B.V. All rights reserved.

Magnesium sulphate as an anticonvulsant in the management of eclampsia

International Nuclear Information System (INIS)

Ahmed, R.

2004-01-01

Objective: To evaluate the use of magnesium sulphate (MgSO/sub 4/) as an anticonvulsant in the management of eclamptic patients. Patients and Methods: Out of a total of 6050 pregnant women, 31 patients had eclampsia and were managed according to the set protocol. MgSO/sub 4/ 'Nas given to eclamptic patients according to protocol who had no contraindication to this agent. Recurrence of convulsion, side effects of magnesium sulphate, maternal and fetal outcome was noted. Results: Over two years' study period, out of 6050 patients, 31 were admitted with eclampsia (0.51 %). There was no maternal death. Out of 31 eclamptic patients only 5 patients were booked. Twenty-two patients (70.9%) were primigravida and 9 (29%) were multigravida. Seventeen (54%) were less than 20 years of age, 22 (79.9%) patients were admitted with antepartum and 6 (19.35%) had postpartum eclampsia. Magnesium sulphate was effective in 29 (93.54%) patients. Fifteen patients delivered by caesarean (C) section and 16 delivered vaginally. Twenty-nine (93.5%) babies were born alive. Two patients had recurrent convulsion i.e. 6.4%. Only one patient had respiratory depression after the use of magnesium sulphate. Conclusion: Eclampsia was well controlled by the use of MgSO/sub 4/. There were only 2 patients who had recurrence of convulsion. Convulsions were controlled in 29 (93.54%) patients despite lack of monitoring facilities of serum magnesium level. (author)

Inovação tecnológica na produção brasileira de sal marinho e as alterações sócioterritoriais dela decorrentes: uma análise sob a ótica da Teoria do Empreendedorismo de Schumpeter / Technological innovation in the production of sea salt in Brazil and changes her socio-territorial arising out: an analysis under the perspective of Schumpeter’s Entrepreneurship Theory

Directory of Open Access Journals (Sweden)

Marco Túlio Mendonça Diniz

2015-12-01

Full Text Available The salt work activity has been practiced extensively throughout the Brazilian coast from Para State to the Rio de Janeiro State, today the mechanized salt industry from the Northern Rio Grande do Norte’s coast produce about 94% of the Brazilian sea salt. The entrepreneurship action of the businessmen who invested in the Rio Grande do Norte’s salt works was primarily responsible for the creation of the current productive structure and internal trade of sea salt, in which the Rio Grande do Norte produces most of this important input to industry and agriculture of the country. The corporate entrepreneurship of the Rio Grande do Norte’s salt works was analyzed from the perspective of Schumpeter’s theory, since they could be identified the five key points of this theory in the development of the Rio Grande do Norte’s salt industry. Taking advantage of the best natural conditions for the installation activity, entrepreneurs have created an environment that can artificially boost, mechanically, the productivity of has industry. Changes in the production structure also caused changes in the spatial structure of areas dedicated to the production of sea salt.

Preliminary petrological and geochemical results from the Salton Sea Geothermal Field, California: A near-field natural analog of a radioactive waste repository in salt: Topical report No. 2

International Nuclear Information System (INIS)

Elders, W.A.; Cohen, L.H.; Williams, A.E.; Neville, S.; Collier, P.; Oakes, C.

1986-03-01

High concentrations of radionuclides and high temperatures are not naturally encountered in salt beds. For this reason, the Salton Sea Geothermal Field (SSGF) may be the best available geologic analog of some of the processes expected to occur in high level nuclear waste repositories in salt. Subsurface temperatures and brine concentrations in the SSGF span most of the temperature range and fluid inclusion brine range expected in a salt repository, and the clay-rich sedimentary rocks are similar to those which host bedded or domal salts. As many of the chemical processes observed in the SSGF are similar to those expected to occur in or near a salt repository, data derived from it can be used in the validation of geochemical models of the near-field of a repository in salt. This report describes preliminary data on petrology and geochemistry, emphasizing the distribution of rare earth elements and U and Th, of cores and cuttings from several deep wells chosen to span a range of temperature gradients and salinities. Subsurface temperature logs have been augmented by fluid inclusion studies, to reveal the effects of brines of varying temperature and salinity. The presence of brines with different oxygen isotopic signatures also indicate lack of mixing. Whole rock major, minor and trace element analyses and data on brine compositions are being used to study chemical migration in these sediments. 65 refs., 20 figs., 3 tabs

Correlation analysis between sulphate content and leaching of sulphates in recycled aggregates from construction and demolition wastes.

Science.gov (United States)

Barbudo, Auxi; Galvín, Adela P; Agrela, Francisco; Ayuso, Jesús; Jiménez, Jose Ramón

2012-06-01

In some recycled aggregates applications, such as component of new concrete or roads, the total content of soluble sulphates should be measured and controlled. Restrictions are usually motivated by the resistance or stability of the new structure, and in most cases, structural concerns can be remedied by the use of techniques such as sulphur-resistant cements. However, environmental risk assessment from recycling and reuse construction products is often forgotten. The purpose of this study is to analyse the content of soluble sulphate on eleven recycled aggregates and six samples prepared in laboratory by the addition of different gypsum percentages. As points of reference, two natural aggregates were tested. An analysis of the content of the leachable amount of heavy metals regulated by European regulation was included. As a result, the correlation between solubility and leachability data allow suggest a limiting gypsum amount of 4.4% on recycled aggregates. This limit satisfies EU Landfill Directive criteria, which is currently used as reference by public Spanish Government for recycled aggregates in construction works. Copyright © 2012 Elsevier Ltd. All rights reserved.

Sulphated glycosaminoglycans and proteoglycans in the developing vertebral column of juvenile Atlantic salmon (Salmo salar).

Science.gov (United States)

Hannesson, Kirsten O; Ytteborg, Elisabeth; Takle, Harald; Enersen, Grethe; Bæverfjord, Grete; Pedersen, Mona E

2015-08-01

In the present study, the distribution of sulphated glycosaminoglycans (GAGs) in the developing vertebral column of Atlantic salmon (Salmo salar) at 700, 900, 1100 and 1400 d° was examined by light microscopy. The mineralization pattern was outlined by Alizarin red S and soft structures by Alcian blue. The temporal and spatial distribution patterns of different types of GAGs: chondroitin-4-sulphate/dermatan sulphate, chondroitin-6-sulphate, chondroitin-0-sulphate and keratan sulphate were addressed by immunohistochemistry using monoclonal antibodies against the different GAGs. The specific pattern obtained with the different antibodies suggests a unique role of the different GAG types in pattern formation and mineralization. In addition, the distribution of the different GAG types in normal and malformed vertebral columns from 15 g salmon was compared. A changed expression pattern of GAGs was found in the malformed vertebrae, indicating the involvement of these molecules during the pathogenesis. The molecular size of proteoglycans (PGs) in the vertebrae carrying GAGs was analysed with western blotting, and mRNA transcription of the PGs aggrecan, decorin, biglycan, fibromodulin and lumican by real-time qPCR. Our study reveals the importance of GAGs in development of vertebral column also in Atlantic salmon and indicates that a more comprehensive approach is necessary to completely understand the processes involved.

Spore-forming, Desulfosporosinus-like sulphate-reducing bacteria from a shallow aquifer contaminated with gasoline.

Science.gov (United States)

Robertson, W J; Franzmann, P D; Mee, B J

2000-02-01

Previous studies on the geochemistry of a shallow unconfined aquifer contaminated with hydrocarbons suggested that the degradation of some hydrocarbons was linked to bacterial sulphate reduction. There was attenuation of naphthalene, 1,3,5-trimethylbenzene (TMB), toluene, p-xylene and ethylbenzene in the groundwater with concomitant loss of sulphate. Here, the recovery of eight strains of sulphate-reducing bacteria (SRB) from the contaminated site is reported. All were straight or curved rod-shaped cells which formed endospores. Amplification and sequencing of the 16S rDNA indicated that the strains were all sulphate reducers of the Gram-positive line of descent, and were most closely related to Desulfosporosinus (previously Desulfotomaculum) orientis DSM 8344 (97-98.9% sequence similarity). The strains clustered in three phylogenetic groups based on 16S rRNA sequences. Whole cell fatty acid compositions were similar to those of D. orientis DSM 8344, and were consistent with previous studies of fatty acids in soil and groundwater from the site. Microcosms containing groundwater from this aquifer indicated a role for sulphate reduction in the degradation of [ring-UL-14C]toluene, but not for the degradation of [UL-14C]benzene which could also be degraded by the microcosms. Adding one of the strains that was isolated from the groundwater (strain T2) to sulphate-enriched microcosms increased the rate of toluene degradation four- to 10-fold but had no effect on the rate of benzene degradation. The addition of molybdate, an inhibitor of sulphate reduction, to the groundwater samples decreased the rate of toluene mineralization. There was no evidence to support the mineralization of [UL-14C]benzene, [ring-UL-14C]toluene or unlabelled m-xylene, p-xylene, ethylbenzene, TMB or naphthalene by any of the strains in pure culture. Growth of all the strains was completely inhibited by 100 micromol l-1 TMB.

Seasonal Variation of the Material Transport Processes in the Ariake Sea

OpenAIRE

Manda, Atsuyoshi; Kanehara, Hisao; Aoshima, Takashi; Kinoshita, Tsukasa; Uchida, Jun; Nakata, Hideaki; Yanagi, Tetsuo

2010-01-01

Seasonal variation of the salt fluxes in the middle part of the Ariake Sea have been investigated by modeling with hydrographic and meteorological data. The salt flux due to the seasonally averaged density-driven currents accounts for approximately 60% of the total salt flux during summer. The salt flux due to the other processes, that are not treated explicitly, such as the tidal pumping, tideinduced residual currents, and short-term variations of the density- and winddriven currents dominat...

The Kotor salt market in the Middle Ages

Directory of Open Access Journals (Sweden)

Malović-Đukić Marica D.

2004-01-01

Full Text Available In this paper, on the basis of some articles of the Statute of Kotor (Cattaro, as well as on the basis of historical documents from the archives in Kotor and Dubrovnik, the author described the Kotor salt market (kumerak solski as one of the legal markets, where commerce of the salt was authorized. The special attention has been given to the participation of the Kotor municipality in this commerce, on one side, and on the other side, on the participation of the Serbian rulers of the Nemanjić dynasty. After Tvrtko's conquest of Kotor in 1384, he took, as the follower of the Nemanjić dynasty, the corresponding share of the Kotor salt custom. After Tvrtko's death in 1391 and weakening of the central power in Bosnia, a part of the Kotor salt market was used by the Bosnian feudal lords. The citizens of Dubrovnik did not pay great attention to the fact, that it was a legal salt market and they used every opportunity to close it, because it was their main rival. During the whole 14th century, they disabled the salt transportation from the sea. They were also destroying the Kotor salt factories in the field of Grbalj.

Determination of Oversulphated Chondroitin Sulphate and Dermatan Sulphate in unfractionated heparin by (1)H-NMR - Collaborative study for quantification and analytical determination of LoD.

Science.gov (United States)

McEwen, I; Mulloy, B; Hellwig, E; Kozerski, L; Beyer, T; Holzgrabe, U; Wanko, R; Spieser, J-M; Rodomonte, A

2008-12-01

Oversulphated Chondroitin Sulphate (OSCS) and Dermatan Sulphate (DS) in unfractionated heparins can be identified by nuclear magnetic resonance spectrometry (NMR). The limit of detection (LoD) of OSCS is 0.1% relative to the heparin content. This LoD is obtained at a signal-to-noise ratio (S/N) of 2000:1 of the heparin methyl signal. Quantification is best obtained by comparing peak heights of the OSCS and heparin methyl signals. Reproducibility of less than 10% relative standard deviation (RSD) has been obtained. The accuracy of quantification was good.

Pressure adaptation is linked to thermal adaptation in salt-saturated marine habitats.

Science.gov (United States)

Alcaide, María; Stogios, Peter J; Lafraya, Álvaro; Tchigvintsev, Anatoli; Flick, Robert; Bargiela, Rafael; Chernikova, Tatyana N; Reva, Oleg N; Hai, Tran; Leggewie, Christian C; Katzke, Nadine; La Cono, Violetta; Matesanz, Ruth; Jebbar, Mohamed; Jaeger, Karl-Erich; Yakimov, Michail M; Yakunin, Alexander F; Golyshin, Peter N; Golyshina, Olga V; Savchenko, Alexei; Ferrer, Manuel

2015-02-01

The present study provides a deeper view of protein functionality as a function of temperature, salt and pressure in deep-sea habitats. A set of eight different enzymes from five distinct deep-sea (3040-4908 m depth), moderately warm (14.0-16.5°C) biotopes, characterized by a wide range of salinities (39-348 practical salinity units), were investigated for this purpose. An enzyme from a 'superficial' marine hydrothermal habitat (65°C) was isolated and characterized for comparative purposes. We report here the first experimental evidence suggesting that in salt-saturated deep-sea habitats, the adaptation to high pressure is linked to high thermal resistance (P value = 0.0036). Salinity might therefore increase the temperature window for enzyme activity, and possibly microbial growth, in deep-sea habitats. As an example, Lake Medee, the largest hypersaline deep-sea anoxic lake of the Eastern Mediterranean Sea, where the water temperature is never higher than 16°C, was shown to contain halopiezophilic-like enzymes that are most active at 70°C and with denaturing temperatures of 71.4°C. The determination of the crystal structures of five proteins revealed unknown molecular mechanisms involved in protein adaptation to poly-extremes as well as distinct active site architectures and substrate preferences relative to other structurally characterized enzymes. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

Salt precipitation and dissolution in the late Quaternary Dead Sea: Evidence from chemical and δ37Cl composition of pore fluids and halites

Science.gov (United States)

Levy, Elan J.; Yechieli, Yoseph; Gavrieli, Ittai; Lazar, Boaz; Kiro, Yael; Stein, Mordechai; Sivan, Orit

2018-04-01

The chemical composition and δ37Cl of pore fluids from the ICDP core drilled in the deepest floor of the terminal and hypersaline Dead Sea, and halites from the adjacent Mount Sedom salt diapir, are used to establish the dynamics of halite precipitation and dissolution during the last interglacial and glacial periods. Between ∼132 and 116 thousand years ago (ka) halites precipitated in the lake resulting in the expulsion of Na+ and Cl- from the residual solution. Over 50% of the Cl- reservoir was removed, resulting in a decrease in the Na/Cl ratio from 0.57 to 0.19. This process was accompanied by a decrease in δ37Cl values in the precipitating halites and the associated residual Cl- in the lake. The observed decrease fits a Rayleigh distillation curve with a fractionation factor of Δ(NaCl-Dead Sea solution) = +0.32‰ (±0.12) determined in the present study. This behavior implies negligible contribution of external sources of Cl- to the lake during the main peak of the last interglacial, MIS5e. Subsequently, during the last glacial (ca. 117 to 17 ka) dissolution of halite took place, the Na+ and Cl- inventory were replenished, accompanied by an increase in Na/Cl from 0.21 to 0.55 and in the δ37Cl values from -0.46‰ to -0.12‰. While the lake underwent significant dilution during that time, the decrease in salinity was somewhat suppressed by the dissolution of the halite which was mostly derived from Mount Sedom salt diapir.

Studies on calcium, magnesium and sulphate in the Mandovi and Zuari river system (Goa)

Digital Repository Service at National Institute of Oceanography (India)

SenGupta, R.; Naik, S.

-conservative parameters. Sulphate, however behaves in a purely conservative manner and remains in a steady state in the rivers. A'Simple mixture'relationship is applied to calculate the dilution and mixing processes in the rivers using calcium, magnesium and sulphate...

Biotreatment of Cr(VI) contaminated waters by sulphate reducing bacteria fed with ethanol

International Nuclear Information System (INIS)

Pagnanelli, F.; Cruz Viggi, C.; Cibati, A.; Uccelletti, D.; Toro, L.; Palleschi, C.

2012-01-01

Highlights: ► Use of ethanol as electron donor for sulphate-reducing bacteria for the treatment of Cr(VI). ► Isolation of contribution in Cr removal (adsorption vs. bioprecipitation). ► Bioassessment of the process effectiveness by ecotoxicological in vivo tests using C. elegans. - Abstract: Biological treatment of Cr(VI) contaminated waters was performed in fixed bed reactors inoculated with SRB (sulphate-reducing bacteria) growing on ethanol. Treatment efficiency was evaluated by checking chemical abatement of Cr(VI) and by ecotoxicological tests using the nematode Caenorhabditis elegans. A preliminary comparison between ethanol and lactate was performed, denoting that using ethanol, the same values of final sulphate abatement were obtained. In addition ethanol showed to be a substrate more competitive than lactate in kinetic terms. Fixed bed column reactors were continuously fed with a solution containing sulphates (3 g L −1 ), ethanol (1.5 g L −1 ) and Cr(VI) (50 mg L −1 ). At steady state the column inoculated with SRB removed 65 ± 5% of sulphate and 95 ± 5% of chromium. Bioactive removal mechanisms predominated over biosorption. Diminution of Cr(VI) toxicity was assessed by using the nematode C. elegans as a test organism showing that the survival of nematodes was 20% in the presence of the untreated influent and raised up to 53% when the nematodes were exposed to the treated effluent.

Factors controlling the compositional variations among the marine and non-marine black shales from Egypt

Energy Technology Data Exchange (ETDEWEB)

Baioumy, Hassan M. [Central Metallurgical R and D Institute, PO Box 87 Helwan, Cairo (Egypt); Ismael, Ismael S. [Faculty of Science, Suez Canal University, Suez (Egypt)

2010-07-01

Index of Alteration (CIA) values in the non-marine black shales compared to the marine black shales suggest a prevailing of more intensive weathering conditions during the Jurassic time in Egypt compared to the Cretaceous. Higher weathering of non-marine shales is compatible with a higher zircon and TiO{sub 2} contents. The higher zircon may account for some of the differences on the contents and mode of occurrence of elements found between the marine and non-marine shales, such as the higher REEs, Nb, Y, and Hf. The higher C{sub org} and Ni/Co, V/Cr, and U/Al ratios in the Red Sea black shales are attributed to more reducing depositional environment of these shales. Marine organic matter seems to be responsible for the selective fixation of some trace elements such as Cr, V, and Zn. Sulfur isotopes from pyrite suggest a marine origin of this pyrite in all shales. However, variations in the {delta}{sup 34}S values reflect variations in the depositional settings. {delta}{sup 34}S data suggest a sulphate-replete (open) system for the pyrite in the Red Sea and lower member (Duwi Formation) of Abu Tartur black shales, sulphate-limited (closed) system in a brackish setting for the Maghara black shales, and coastal plain setting in the middle member of Abu Tartur area. The similarities among marine and non-marine black shales such as positive correlations between Zr and both Nb and Hf as well as between Fe{sub 2}O{sub 3} and Co might reflect the geochemical behaviors of such elements rather than variations in the provenances and/or depositional environments. (author)

Shelf-to-basin iron shuttling enhances vivianite formation in deep Baltic Sea sediments

Science.gov (United States)

Reed, Daniel C.; Gustafsson, Bo G.; Slomp, Caroline P.

2016-01-01

Coastal hypoxia is a growing and persistent problem largely attributable to enhanced terrestrial nutrient (i.e., nitrogen and phosphorus) loading. Recent studies suggest phosphorus removal through burial of iron (II) phosphates, putatively vivianite, plays an important role in nutrient cycling in the Baltic Sea - the world's largest anthropogenic dead zone - yet the dynamics of iron (II) phosphate formation are poorly constrained. To address this, a reactive-transport model was used to reconstruct the diagenetic and depositional history of sediments in the Fårö basin, a deep anoxic and sulphidic region of the Baltic Sea where iron (II) phosphates have been observed. Simulations demonstrate that transport of iron from shelf sediments to deep basins enhances vivianite formation while sulphide concentrations are low, but that pyrite forms preferentially over vivianite when sulphate reduction intensifies due to elevated organic loading. Episodic reoxygenation events, associated with major inflows of oxic waters, encourage the retention of iron oxyhydroxides and iron-bound phosphorus in sediments, increasing vivianite precipitation as a result. Results suggest that artificial reoxygenation of the Baltic Sea bottom waters could sequester up to 3% of the annual external phosphorus loads as iron (II) phosphates, but this is negligible when compared to potential internal phosphorus loads due to dissolution of iron oxyhydroxides when low oxygen conditions prevail. Thus, enhancing vivianite formation through artificial reoxygenation of deep waters is not a viable engineering solution to eutrophication in the Baltic Sea. Finally, simulations suggest that regions with limited sulphate reduction and hypoxic intervals, such as eutrophic estuaries, could act as important phosphorus sinks by sequestering vivianite. This could potentially alleviate eutrophication in shelf and slope environments.

Contrasting records of sea-level change in the eastern and western North Atlantic during the last 300 years

Science.gov (United States)

Long, A. J.; Barlow, N. L. M.; Gehrels, W. R.; Saher, M. H.; Woodworth, P. L.; Scaife, R. G.; Brain, M. J.; Cahill, N.

2014-02-01

We present a new 300-year sea-level reconstruction from a salt marsh on the Isle of Wight (central English Channel, UK) that we compare to other salt-marsh and long tide-gauge records to examine spatial and temporal variability in sea-level change in the North Atlantic. Our new reconstruction identifies an overall rise in relative sea level (RSL) of c. 0.30 m since the start of the eighteenth century at a rate of 0.9±0.3 mm yr. Error-in-variables changepoint analysis indicates that there is no statistically significant deviation from a constant rate within the dataset. The reconstruction is broadly comparable to other tide-gauge and salt-marsh records from the European Atlantic, demonstrating coherence in sea level in this region over the last 150-300 years. In contrast, we identify significant differences in the rate and timing of RSL with records from the east coast of North America. The absence of a strong late 19th/early 20th century RSL acceleration contrasts with that recorded in salt marsh sediments along the eastern USA coastline, in particular in a well-dated and precise sea-level reconstruction from North Carolina. This suggests that this part of the North Carolina sea level record represents a regionally specific sea level acceleration. This is significant because the North Carolina record has been used as if it were globally representative within semi-empirical parameterisations of past and future sea-level change. We conclude that regional-scale differences of sea-level change highlight the value of using several, regionally representative RSL records when calibrating and testing semi-empirical models of sea level against palaeo-records. This is because by using records that potentially over-estimate sea-level rise in the past such models risk over-estimating sea-level rise in the future.

Formulation and evaluation and terbutaline sulphate and ...

African Journals Online (AJOL)

We report the use of low rugosity lactose, product of controlled crystallization of this carrier, in the formulation of terbutaline sulphate and beclomethasone dipropionate dry powder inhalers. The deposition patterns obtained with inhalation mixtures consisting of the modified lactose and each of the micronised drugs ...

Occurrence of organohalogens at the Dead Sea Basin

Science.gov (United States)

Tubbesing, Christoph; Kotte, Karsten; Keppler, Frank; Krause, Torsten; Bahlmann, Enno; Schöler, Heinfried

2013-04-01

Most arid and semi-arid regions are characterized by evaporites, which are assured sources for volatile organohalogens (VOX) [1]. These compounds play an important role in tropospheric and stratospheric chemistry. The Dead Sea between Israel and Jordan is the world's most famous and biggest all-season water covered salt lake. In both countries chemical plants like the Dead Sea Works and the Arab Potash Company are located at the southern part of the Dead Sea and mine various elements such as bromine and magnesium. Conveying sea water through constructed evaporation pans multifarious salts are enriched and precipitated. In contrast, the Northern basin and main part of the Dead Sea has remained almost untouched by industrial salt production. Its fresh water supply from the Jordan River is constantly decreasing, leading to further increased salinity. During a HALOPROC campaign (Natural Halogenation Processes in the Environment) we collected various samples including air, soils, sediments, halophytic plants, ground- and seawater from the Northern and Southern basin of the Israeli side of the Dead Sea. These samples were investigated for the occurrence of halocarbons using different analytical techniques. Most samples were analyzed for volatile organohalogens such as haloalkanes using gas chromatography- mass spectrometry (GC-MS). Interestingly, there is a strong enrichment of trihalomethanes (THM), especially all chlorinated and brominated ones and also the iodinated compound dichloroiodomethane were found in the Southern basin. In addition, volatile organic carbons (VOC) such as ethene and some other alkenes were analyzed by a gas chromatography-flame ionisation detector (GC-FID) to obtain further information about potential precursors of halogenated compounds. Halophytic plants were investigated for their potential to release chloromethane and bromomethane but also for their stable carbon and hydrogen isotope composition. For this purpose, a plant chamber was

Wetland Loss Patterns and Inundation-Productivity Relationships Prognosticate Widespread Salt Marsh Loss for Southern New England

Science.gov (United States)

Tidal salt marsh is a key defense against, yet is especially vulnerable to, the effects of accelerated sea level rise. To determine whether salt marshes in southern New England will be stable given increasing inundation over the coming decades, we examined current loss patterns, ...

Salt Marshes as Monitors of Late Holocene Outlet Glacier Retreat

Science.gov (United States)

Wake, L. M.; Woodroffe, S.; Long, A. J.; Milne, G. A.

2014-12-01

New proxy sea-level records extracted from salt marshes in the vicinity of Jakobshavn Isbrae (Pakitsoq; 69.51°N, 50.74°W) and at previous sites in central western Greenland (Sisimiut; 66.47°N, 53.61°W and Aasiaat; 68.69°N, 52.88°W) are analyzed with respect to their ability to act as proximal tide gauges detecting mass balance changes in nearby outlet glaciers associated with the transition from the Little Ice Age ("LIA", 1400-1850AD) to the Industrial Period (>1850AD). Data at Pakitsoq demonstrate that sea-level rose at a rate of 3.5 ±1.7 mm/yr prior to 1850AD and slowed to 0.3 ±0.6mm/yr thereafter, producing a slowdown in sea level of 3.2 ± 1.8 mm/yr. A similar slowdown, occurring at 1600AD, is observed at Aasiaat and Sisimiut. We interpret these observed changes using a glacial isostatic adjustment model of sea-level change truncated at degree and order 4096, with an aim to determine if the sea-level data can be used to place constraints on changes in Jakobshavn Isbrae and/or Kangiata Nunaata Sermia (Nuuk fjord) during this period. Modelled sea level at Pakitsoq is insensitive to the location of thickening (thinning) associated with grounding line advance (retreat) and the rate of advance and retreat but is sensitive to the change point in time between periods of growth associated with LIA expansion (sea level rise) and the onset of 19th century recession (sea level fall) of Jakobshavn Isbrae. We conclude that the change in sea-level rate observed at Pakitsoq circa 1850AD marks the onset of post LIA retreat of this outlet glacier. Conversely, the modelled sea-level response to the retreat of Kangiata Nunaata Sermia from its LIA maximum at ca. 1761AD is below the detection threshold of the salt marsh record at Sisimiut.

Arctic sea ice a major determinant in Mandt's black guillemot movement and distribution during non-breeding season

Science.gov (United States)

Divoky, G.J.; Douglas, David C.; Stenhouse, I. J.

2016-01-01

Mandt's black guillemot (Cepphus grylle mandtii) is one of the few seabirds associated in all seasons with Arctic sea ice, a habitat that is changing rapidly. Recent decreases in summer ice have reduced breeding success and colony size of this species in Arctic Alaska. Little is known about the species' movements and distribution during the nine month non-breeding period (September–May), when changes in sea ice extent and composition are also occurring and predicted to continue. To examine bird movements and the seasonal role of sea ice to non-breeding Mandt's black guillemots, we deployed and recovered (n = 45) geolocators on individuals at a breeding colony in Arctic Alaska during 2011–2015. Black guillemots moved north to the marginal ice zone (MIZ) in the Beaufort and Chukchi seas immediately after breeding, moved south to the Bering Sea during freeze-up in December, and wintered in the Bering Sea January–April. Most birds occupied the MIZ in regions averaging 30–60% sea ice concentration, with little seasonal variation. Birds regularly roosted on ice in all seasons averaging 5 h d−1, primarily at night. By using the MIZ, with its roosting opportunities and associated prey, black guillemots can remain in the Arctic during winter when littoral waters are completely covered by ice.

Magnesium sulphate for women at risk of preterm birth for neuroprotection of the fetus

NARCIS (Netherlands)

Doyle, Lex W.; Crowther, Caroline A.; Middleton, Philippa; Marret, Stephane; Rouse, Dwight

2009-01-01

Background Epidemiological and basic science evidence suggests that magnesium sulphate before birth may be neuroprotective for the fetus. Objectives To assess the effects of magnesium sulphate as a neuroprotective agent when given to women considered at risk of preterm birth. Search strategy We

Phase transformation of aluminium hydroxide to aα- alumina prepared from different aluminium salts

International Nuclear Information System (INIS)

Masliana Muslimin; Meor Yusoff Meor Sulaiman

2006-01-01

The study intends to look at the most suitable aluminium salt to produce a single-phase a-alumina by the hydrothermal method. In the process to produce alumina from the calcination of aluminium hydroxide (Al(OH) 3 ), three different aluminium salts namely aluminium sulfate (Al 2 (SO 4) 2), aluminium nitrate (A(NO 3 ) 3 ) and aluminium chloride (AlCl 3 ) were tried. The process involved the used of NH 4 OH as the precipitating medium. Aluminium hydroxide produced from each of these salts were characterised by x-ray diffraction (XRD) technique to identity the crystalline phase. Aluminium hydroxide produced by all the different aluminium salts is present as boehmite or pseudo-boehmite phase. Aluminium hydroxide produced from Al 2 (SO) 2 , Al(NO) 3 and AlCl 3 shows the transformation of the boehmite phase to a α-alumina phase at 500 0 C. On further heating, the α-alumina continuously formed at 800 o C followed soon at 1000 o C. But for the Al(NO3) 3 salts a different phase transitions occurs on heating especially at 1000 o C. Here it was observed not a single alumina phase is presence but the presence of both α and γ--alumina phases. At 1300 o C, the single α-alumina phase was formed. The study concluded that aluminium sulphate is recommended in order to obtain a single-phase α-alumina with the required characteristics. (Author)

Biogeographical diversity of leaf-associated microbial communities from salt-secreting Tamarix trees of the Dead Sea region.

Science.gov (United States)

Qvit-Raz, Noga; Finkel, Omri M; Al-Deeb, Taghleb M; Malkawi, Hanan I; Hindiyeh, Muna Y; Jurkevitch, Edouard; Belkin, Shimshon

2012-02-01

The leaves of Tamarix, a salt-secreting desert tree, form an extreme niche that harbors a unique microbial community. In view of the global distribution of this tree, its island-like phyllosphere is highly suitable for studying microbial diversity along geographical gradients. Here we present an analysis of microbial community diversity using leaf surface samples collected at six different sites, on both sides of the Dead Sea, over a period of one year. Biodiversity analysis of denaturing gradient gel electrophoresis (DGGE) patterns of the bacterial 16S rRNA gene revealed a significant degree of bacterial community similarity within trees sampled at the same site, much higher than the similarity between trees from different geographical locations. Statistical analysis indicated that the degree of similarity was negatively correlated with the distance between sampling sites, and that a weak correlation existed between diversity and leaf pH. Copyright © 2011 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Automatic colorimetric determination of low concentrations of sulphate for measuring sulphur dioxide in ambient air

Energy Technology Data Exchange (ETDEWEB)

Persson, G A

1966-01-01

An automatic colorimetric method for the determination of low concentrations of sulphate (0-10 microgram/ml) using the thoron indicator is described. Total amounts of sulphate as small as 0.3 micrograms can be determined. The sulphate is precipitated with barium perchlorate and the excess of barium is indicated with 1-(o-arsenophenylazo)-2-naphthol-3-6-disulfonic acid(thoron). The procedure is worked out primarily for the determination of sulphur dioxide in air after absorption in diluted hydrogen peroxide.

Context-driven Salt Seeking Test (Rats)

Science.gov (United States)

Chang, Stephen E.; Smith, Kyle S.

2018-01-01

Changes in reward seeking behavior often occur through incremental learning based on the difference between what is expected and what actually happens. Behavioral flexibility of this sort requires experience with rewards as better or worse than expected. However, there are some instances in which behavior can change through non-incremental learning, which requires no further experience with an outcome. Such an example of non-incremental learning is the salt appetite phenomenon. In this case, animals such as rats will immediately seek out a highly-concentrated salt solution that was previously undesired when they are put in a novel state of sodium deprivation. Importantly, this adaptive salt-seeking behavior occurs despite the fact that the rats never tasted salt in the depleted state, and therefore never tasted it as a highly desirable reward. The following protocol is a method to investigate the neural circuitry mediating adaptive salt seeking using a conditioned place preference (CPP) procedure. The procedure is designed to provide an opportunity to discover possible dissociations between the neural circuitry mediating salt seeking and salt consumption to replenish the bodily deficit after sodium depletion. Additionally, this procedure is amenable to incorporating a number of neurobiological techniques for studying the brain basis of this behavior.

Modelling the competition between sulphate reducers and methanogens in a thermophilic methanol-fed bioreactor

NARCIS (Netherlands)

Spanjers, H.; Weijma, J.; Abusam, A.

2002-01-01

Sulphate can be removed from wastewater by means of biological anaerobic reduction to sulphide. The reduction requires the presence of a substrate that can serve as an electron donor. Methanol a suitable electron donor for sulphate reduction under thermophilic conditions. In an anaerobic system

Integrating Non-Tidal Sea Level data from altimetry and tide gauges for coastal sea level prediction

DEFF Research Database (Denmark)

Cheng, Yongcun; Andersen, Ole Baltazar; Knudsen, Per

2012-01-01

The main objective of this paper is to integrate Non-Tidal Sea Level (NSL) from the joint TOPEX, Jason-1 and Jason-2 satellite altimetry with tide gauge data at the west and north coast of the United Kingdom for coastal sea level prediction. The temporal correlation coefficient between altimetric...... NSLs and tide gauge data reaches a maximum higher than 90% for each gauge. The results show that the multivariate regression approach can efficiently integrate the two types of data in the coastal waters of the area. The Multivariate Regression Model is established by integrating the along-track NSL...... from the joint TOPEX/Jason-1/Jason-2 altimeters with that from eleven tide gauges. The model results give a maximum hindcast skill of 0.95, which means maximum 95% of NSL variance can be explained by the model. The minimum Root Mean Square Error (RMSe) between altimetric observations and model...

Performance of Electrocoagulation Process for Removal of Sulphate Ion from Aqueous Environments Using Plate Aluminum Electrodes

Directory of Open Access Journals (Sweden)

a.h Mahvi

2012-05-01

Full Text Available

Background and Objectives: Sulphate ion is one of the main ions available in natural and waste water. The high rate of sulphate in drinking water causes health problems such as irritation and digestive problems and makes water taste bitter. The purpose of this study was to assess the efficiency of sulphate ion removal from drinking water through Electrocogualation process (EC using plate aluminum electrodes. Methods: This study was conducted as a pilot plant using one glass tank in the volume of 1.3liter containing 6 plate aluminum electrodes. These electrodes were attached to a power supply in a mono-polar and parallel arrangement in order to switch the alternating current to the direct one. That is, each electrode was attached to positive and negative poles directly and alternately. The tank was filled with synthetic water containing sulphate ion with the concentration of 350 & 700mg/L. Percentage of sulphate ion removal in potential range of 10, 20 and 30 V, reaction times of 40, 20 and 60min and pH 7.0, 3.0 & 11.0 were measured. Results: In this study the maximum efficiency of sulphate ion removal was in the electrical potential of 30 V, reaction time of 60min and pH 11.0. With increase of ion concentration, the time needed to achieve a suitable efficiency of removal increased, that is, it indicated the direct effect of pH and difference of electrical potential on removal of sulphate ion through EC process. Conclusion: The results of this research show that Electrocogualation technology can be introduced as a suitable and promising technique to remove sulphate ion from aqueous environments using plate aluminum electrodes.

Performance of Electrocoagulation Process for Removal of Sulphate Ion from Aqueous Environments Using Plate Aluminum Electrodes

Directory of Open Access Journals (Sweden)

Rajabizadeh A.

2010-09-01

Full Text Available Background and Objectives: Sulphate ion is one of the main ions available in natural and waste water. The high rate of sulphate in drinking water causes health problems such as irritation and digestive problems and makes water taste bitter. The purpose of this study was to assess the efficiency of sulphate ion removal from drinking water through Electrocogualation process (EC using plate aluminum electrodes.Methods: This study was conducted as a pilot plant using one glass tank in the volume of 1.3liter containing 6 plate aluminum electrodes. These electrodes were attached to a power supply in a mono-polar and parallel arrangement in order to switch the alternating current to the direct one. That is, each electrode was attached to positive and negative poles directly and alternately. The tank was filled with synthetic water containing sulphate ion with the concentration of 350 & 700mg/L. Percentage of sulphate ion removal in potential range of 10, 20 and 30 V, reaction times of 40, 20 and 60min and pH 7.0, 3.0 & 11.0 were measured.Results: In this study the maximum efficiency of sulphate ion removal was in the electrical potential of 30 V, reaction time of 60min and pH 11.0. With increase of ion concentration, the time needed to achieve a suitable efficiency of removal increased, that is, it indicated the direct effect of pH and difference of electrical potential on removal of sulphate ion through EC process.Conclusion: The results of this research show that Electrocogualation technology can be introduced as a suitable and promising technique to remove sulphate ion from aqueous environments using plate aluminum electrodes.

Sulphate Potasium Extraction From Banana Stem Ash with Bleaching Earth Waste Liquid

OpenAIRE

Edahwati, Luluk

2010-01-01

Sulphate potassium is one of the important chemistry compound for industrial at our country, usually for fertilizerindustry. Therefore, necessary done sulphate potassium maker watchfulness from various ingredient that containsulphate potassium compound. Among others with extract banana stem ash. Watchfulness methodology that is withmix banana stem ash with aquadest (20 gram ash/1 water litre) in temperature 100oc during 30 minutes and stirringrotation 300 rpm. Ash extract that got reaction wi...

Toxicology studies of primycin-sulphate using a three-dimensional (3D) in vitro human liver aggregate model.

Science.gov (United States)

Pénzes, Ágota; Mahmud Abdelwahab, Elhusseiny Mohamed; Rapp, Judit; Péteri, Zsanett A; Bovári-Biri, Judit; Fekete, Csaba; Miskei, György; Kvell, Krisztián; Pongrácz, Judit E

2017-11-05

Primycin-sulphate is a highly effective compound against Gram (G) positive bacteria. It has a potentially synergistic effect with vancomycin and statins which makes primycin-sulphate a potentially very effective preparation. Primycin-sulphate is currently used exclusively in topical preparations. In vitro animal hepatocyte and neuromuscular junction studies (in mice, rats, snakes, frogs) as well as in in vitro human red blood cell experiments were used to test toxicity. During these studies, the use of primycin-sulphate resulted in reduced cellular membrane integrity and modified ion channel activity. Additionally, parenteral administration of primycin-sulphate to mice, dogs, cats, rabbits and guinea pigs indicated high level of acute toxicity. The objective of this study was to reveal the cytotoxic and gene expression modifying effects of primycin-sulphate in a human system using an in vitro, three dimensional (3D) human hepatic model system. Within the 3D model, primycin-sulphate presented no acute cytotoxicity at concentrations 1μg/ml and below. However, even at low concentrations, primycin-sulphate affected gene expressions by up-regulating inflammatory cytokines (e.g., IL6), chemokines (e.g., CXCL5) and by down-regulating molecules of the lipid metabolism (e.g., peroxisome proliferator receptor (PPAR) alpha, gamma, etc). Down-regulation of PPAR alpha cannot just disrupt lipid production but can also affect cytochrome P450 metabolic enzyme (CYP) 3A4 expression, highlighting the need for extensive drug-drug interaction (DDI) studies before human oral or parenteral preparations can be developed. Copyright © 2017 Elsevier B.V. All rights reserved.

Tests of the salt-nuclei hypothesis of rain formation

Energy Technology Data Exchange (ETDEWEB)

Woodcock, A H; Blanchard, D C

1955-01-01

Atmospheric chlorides in sea-salt nuclei and the chlorides dissolved in shower rainwaters were recently measured in Hawaii. A comparison of these measurements reveals the remarkable fact that the weight of chloride present in a certain number of nuclei in a cubic meter of clear air tends to be equal to the weight of chloride dissolved in an equal number of raindrops in a cubic meter of rainy air. This result is explained as an indication that the raindrops grow on the salt nuclei in some manner which prevents a marked change in the distribution of these nuclei during the drop-growth process. The data presented add new evidence in further support of the salt-nuclei raindrop hypothesis previously proposed by the first author.

Evaluating portland cement concrete degradation by sulphate exposure through artificial neural networks modeling

International Nuclear Information System (INIS)

Oliveira, Douglas Nunes de; Bourguignon, Lucas Gabriel Garcia; Tolentino, Evandro; Costa, Rodrigo Moyses; Tello, Cledola Cassia Oliveira de

2015-01-01

A concrete is durable if it has accomplished the desired service life in the environment in which it is exposed. The durability of concrete materials can be limited as a result of adverse performance of its cement-paste matrix or aggregate constituents under either chemical or physical attack. Among other aggressive chemical exposures, the sulphate attack is an important concern. Water, soils and gases, which contain sulphate, represent a potential threat to the durability of concrete structures. Sulphate attack in concrete leads to the conversion of the hydration products of cement to ettringite, gypsum, and other phases, and also it leads to the destabilization of the primary strength generating calcium silicate hydrate (C-S-H) gel. The formation of ettringite and gypsum is common in cementitious systems exposed to most types of sulphate solutions. The present work presents the application of the neural networks for estimating deterioration of various concrete mixtures due to exposure to sulphate solutions. A neural networks model was constructed, trained and tested using the available database. In general, artificial neural networks could be successfully used in function approximation problems in order to approach the data generation function. Once data generation function is known, artificial neural network structure is tested using data not presented to the network during training. This paper is intent to provide the technical requirements related to the production of a durable concrete to be used in the structures of the Brazilian near-surface repository of radioactive wastes. (author)

Biotreatment of Cr(VI) contaminated waters by sulphate reducing bacteria fed with ethanol

Energy Technology Data Exchange (ETDEWEB)

Pagnanelli, F., E-mail: francesca.pagnanelli@uniroma1.it [Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome (Italy); Cruz Viggi, C., E-mail: carolina.cruzviggi@uniroma1.it [Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome (Italy); Cibati, A., E-mail: alessio.cibati@uniroma1.it [Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome (Italy); Uccelletti, D., E-mail: daniela.uccelletti@uniroma1.it [Department of Biology and Biotechnology, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome (Italy); Toro, L., E-mail: luigi.toro@uniroma1.it [Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome (Italy); Palleschi, C., E-mail: claudio.palleschi@uniroma1.it [Department of Biology and Biotechnology, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome (Italy)

2012-01-15

Highlights: Black-Right-Pointing-Pointer Use of ethanol as electron donor for sulphate-reducing bacteria for the treatment of Cr(VI). Black-Right-Pointing-Pointer Isolation of contribution in Cr removal (adsorption vs. bioprecipitation). Black-Right-Pointing-Pointer Bioassessment of the process effectiveness by ecotoxicological in vivo tests using C. elegans. - Abstract: Biological treatment of Cr(VI) contaminated waters was performed in fixed bed reactors inoculated with SRB (sulphate-reducing bacteria) growing on ethanol. Treatment efficiency was evaluated by checking chemical abatement of Cr(VI) and by ecotoxicological tests using the nematode Caenorhabditis elegans. A preliminary comparison between ethanol and lactate was performed, denoting that using ethanol, the same values of final sulphate abatement were obtained. In addition ethanol showed to be a substrate more competitive than lactate in kinetic terms. Fixed bed column reactors were continuously fed with a solution containing sulphates (3 g L{sup -1}), ethanol (1.5 g L{sup -1}) and Cr(VI) (50 mg L{sup -1}). At steady state the column inoculated with SRB removed 65 {+-} 5% of sulphate and 95 {+-} 5% of chromium. Bioactive removal mechanisms predominated over biosorption. Diminution of Cr(VI) toxicity was assessed by using the nematode C. elegans as a test organism showing that the survival of nematodes was 20% in the presence of the untreated influent and raised up to 53% when the nematodes were exposed to the treated effluent.

Evaluating portland cement concrete degradation by sulphate exposure through artificial neural networks modeling

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Douglas Nunes de; Bourguignon, Lucas Gabriel Garcia; Tolentino, Evandro, E-mail: tolentino@timoteo.cefetmg.br [Centro Federal de Educacao Tecnologica de Minas Gerais (CEFET-MG), Timoteo, MG (Brazil); Costa, Rodrigo Moyses, E-mail: rodrigo@moyses.com.br [Universidade de Itauna, Itauna, MG (Brazil); Tello, Cledola Cassia Oliveira de, E-mail: tellocc@cdtn.br [Centro de Desenvolvimento da Tecnologia Nucelar (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2015-07-01

A concrete is durable if it has accomplished the desired service life in the environment in which it is exposed. The durability of concrete materials can be limited as a result of adverse performance of its cement-paste matrix or aggregate constituents under either chemical or physical attack. Among other aggressive chemical exposures, the sulphate attack is an important concern. Water, soils and gases, which contain sulphate, represent a potential threat to the durability of concrete structures. Sulphate attack in concrete leads to the conversion of the hydration products of cement to ettringite, gypsum, and other phases, and also it leads to the destabilization of the primary strength generating calcium silicate hydrate (C-S-H) gel. The formation of ettringite and gypsum is common in cementitious systems exposed to most types of sulphate solutions. The present work presents the application of the neural networks for estimating deterioration of various concrete mixtures due to exposure to sulphate solutions. A neural networks model was constructed, trained and tested using the available database. In general, artificial neural networks could be successfully used in function approximation problems in order to approach the data generation function. Once data generation function is known, artificial neural network structure is tested using data not presented to the network during training. This paper is intent to provide the technical requirements related to the production of a durable concrete to be used in the structures of the Brazilian near-surface repository of radioactive wastes. (author)

Hexagonal ZnO porous plates prepared from microwave synthesized layered zinc hydroxide sulphate via thermal decomposition

Energy Technology Data Exchange (ETDEWEB)

Machovsky, Michal, E-mail: machovsky@ft.utb.cz [Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Nad Ovcirnou 3685, 760 01 Zlin (Czech Republic); Polymer Centre, Faculty of Technology, Tomas Bata University in Zlin, Nam. T.G. Masaryka 275, 762 72 Zlin (Czech Republic); Kuritka, Ivo, E-mail: ivo@kuritka.net [Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Nad Ovcirnou 3685, 760 01 Zlin (Czech Republic); Polymer Centre, Faculty of Technology, Tomas Bata University in Zlin, Nam. T.G. Masaryka 275, 762 72 Zlin (Czech Republic); Sedlak, Jakub, E-mail: j1sedlak@ft.utb.cz [Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Nad Ovcirnou 3685, 760 01 Zlin (Czech Republic); Polymer Centre, Faculty of Technology, Tomas Bata University in Zlin, Nam. T.G. Masaryka 275, 762 72 Zlin (Czech Republic); Pastorek, Miroslav, E-mail: pastorek@ft.utb.cz [Centre of Polymer Systems, University Institute, Tomas Bata University in Zlin, Nad Ovcirnou 3685, 760 01 Zlin (Czech Republic); Department of Polymer Engineering, Faculty of Technology, Tomas Bata University in Zlin, Nam. T.G. Masaryka 275, 762 72 Zlin (Czech Republic)

2013-10-15

Graphical abstract: - Highlights: • Zinc hydroxy sulphate was synthesized in 3 min via microwave hydrothermal route. • Zinc hydroxy sulphate was converted into mesh like porous ZnO by calcining at 900°. • The process of transformation is topotactic. - Abstract: Layered zinc hydroxide sulphate (ZHS) was prepared by microwave-assisted hydrothermal precipitation of zinc sulphate monohydrate with hexamethylenetetramine. Under ambient conditions, the structure of ZHS determined by X-ray diffraction (XRD) was found to be a mixture of zinc hydroxide sulphate pentahydrate Zn{sub 4}SO{sub 4}(OH){sub 6}·5H{sub 2}O and tetrahydrate Zn{sub 4}SO{sub 4}(OH){sub 6}·4H{sub 2}O. Fourier transform infrared (FTIR) spectroscopy was used for characterization of the prepared materials. Based on the interpretation of ZHS's thermal decomposition profile obtained by thermogravimetric analysis, ZnO of high purity was prepared by calcination at 900 °C for 2 h. The structure of the resulting ZnO was confirmed by the XRD. The morphology examination by scanning electron microscopy revealed a porous mesh-like ZnO structure developed from the ZHS precursor at the expense of mass removal due to the release of water and sulphate during the calcination.

Intoxication experiments with beryllium sulphate

International Nuclear Information System (INIS)

Bucurescu, I.; Stan, T.

1990-01-01

The changes in the particular number of animals in two groups of 40 rats each subjected to intoxication experiments with beryllium sulphate was investigated. The two investigations had very different characteristics. In the case of chronic intoxication there was a marked lethality over given time intervals. In the case of subacute intoxication the number of animals decreased with time. It was found empirically that this change can be described by an exponential relationship which lends itself to statistical interpretation. (author)

Comparison of methods for the determination of reduced inorganic sulphur in acid sulphate soils

International Nuclear Information System (INIS)

Santomartino, S.L.

1999-01-01

Full text: The management of acid sulphate soils requires analytical methods that provide accurate data on the quantity of reduced inorganic sulphur within a soil, as it is this fraction that produces acid upon oxidation. This study uses sulphidic Coode Island Silt samples to compare common analytical methods including POCAS (Peroxide Oxidation-Combined Acidity and Sulphate) which consists of TSA (Total Sulphidic Acidity), S pos (Peroxide Oxidisable Sulphur), TOS (Total Oxidisable Sulphur) and chromium-reducible sulphur. The determination of total sulphur by Leco sulphur is strongly correlated with, but slightly less than, that analysed by XRF. Comparison of soil sulphide content by chromium-reducible sulphur, TSA and TOS methods indicates that TOS values are substantially higher than both other methods. The problem with the TOS method lies in the sulphate extraction procedure. Hot distilled water and HCI are commonly used as extractants, however hot distilled water fails to remove organic sulphur, thereby overestimating the sulphide content of the soil. Leco carbon analyses verify that a substantial proportion of organic matter exists within the samples. The HCI extraction process, which uses Ion Chromatography to analyse for sulphate, produces highly inaccurate results due to the interference of the sulphate peak by the chloride peak during analysis. An alternative method involving HCI extraction and XRF analysis of the soil residue is currently being undertaken. The use of KCI to extract sulphate generally produces values similar to the hot distilled water method. The sulphidic content measured by TSA is strongly correlated with, but slightly higher than that determined by the chromium-reducible sulphur method. This is attributed to the use of hydrogen peroxide in the TSA method, which oxidises organic matter to organic acids in addition to oxidising sulphides. These preliminary findings indicate that the chromium-reducible sulphur method is the most suitable

Mineralogical study of stream waters and efflorescent salts in Sierra Minera, SE Spain

Science.gov (United States)

Pérez-Sirvent, Carmen; Garcia-Lorenzo, Maria luz; Martinez-Sanchez, Maria Jose; Hernandez, Carmen; Hernandez-Cordoba, Manuel

2015-04-01

sample collected in A5 is strongly influenced by a tailing dump, and showed high trace element contents. In addition, is influenced by the sea water and then showed high bromide, chloride, sodium and magnesium content, together with a basic pH.The DRX results of evaporate water showed that halite, hexahydrite and gypsum are present: halite corroborates the sea influence and gypsum and hexahydrite the importance of soluble sulphates. A9 water showed acid pH and high trace elements content; is influenced by the tailing dump and also by waters from El Beal gully watercourse, transporting materials from Sierra Minera Waters affected by secondary contamination are influenced by mining wastes, the sea water and also are affected by agricultural activities (nitrate content). These waters have been mixed with carbonate materials, present in the zone increasing the pH. Some elements have precipitated, such as Cu and Pb, while Cd, Zn and As are soluble. The DRX analysis in the evaporate if A14 showed that halite and gypsum are present: halite confirms the seawater influence and gypsum the relationship between calcium and sulphates A2 and A6 waters are affected by tertiary contamination and showed basic pH, soluble carbonates and lower trace element content. Only Zn, Cd and Al are present. Zone B: All waters are strongly affected by mining activities and showed: acid pH, high trace element content and high content of soluble sulphates. The evaporate of B8 and B12 showed the presence of soluble sulphates: gypsum, halite, bianchite, paracoquimbite, halotrichite and siderotil in B8; gypsum, bianchite, paracoquimbite and coquimbite in B12; gypsum, hexahydrite, carnalite, bianchite, copiapite and sideroti in B10 and polihalite, gypsum, bianchite, coquimbite and paracoquimbite in B14. All the sampling points collected in Zone C are affected by primary contamination, because there are a lot of tailing dumps and sampling points are located close to them. C1 showed high trace element

Green chemical incorporation of sulphate into polyoxoanions of ...

Indian Academy of Sciences (India)

Green chemical incorporation of sulphate into polyoxoanions of molybdenum to nano level ... Keywords. Polyoxometalate; green synthesis; nanostructures; surfactant. ... The effects of reaction parameters such as concentration of surfactant, temperature and pH of solution on the synthesis of nanospheres were investigated.

Analgesic effect of intra-articular magnesium sulphate compared with bupivacaine after knee arthroscopic menisectomy

Directory of Open Access Journals (Sweden)

Yasser A. Radwan

2013-07-01

Full Text Available This work aimed to evaluate the analgesic efficacy of intra-articular injection of magnesium sulphate (4% compared with equivalent volume of bupivacaine (0.5% after outpatient knee arthroscopic meniscectomy. Forty patients were randomly assigned to two groups. Group M (n = 20 received intra-articular magnesium sulphate 4%, group B (n = 20 received bupivacaine (0.5%. Analgesic effect was evaluated by analgesic duration, and by measuring pain intensity at 1, 2, 4, 6, 12, 24 h both at rest and on knee movement to 90°. The primary outcome variable was pain intensity on the VAS at 1, 2, 4, 6, 12, 24 h post arthroscopy at rest and on movement (flexion of knee to 90°, although the magnesium group had lower time weighted averages (TWAs at rest and on movement, these TWAs were not statistically significant. The median duration of postoperative analgesia was significantly longer in the patients treated with magnesium sulphate (528 min than in the bupivacaine group (317 min (p < 0.0001, with less number of patients needing supplementary analgesia in magnesium group (8/20 than those of the bupivacaine group (16/20 (p < 0.022. Also analgesic consumption was significantly lower in the magnesium sulphate group (p < 0.002. We concluded that the use of magnesium sulphate is rational and effective in reducing pain, and is more physiological and shortens convalescence after outpatient arthroscopic meniscectomy, however our hypotheses that analgesic efficacy of intra-articular isotonic magnesium sulphate would be superior to intra-articular local anaesthetic cannot be supported with this study.