A literature review of the saturation state of seawater with respect to calcium carbonate and its possible significance for scale formation on OTEC heat exchangers     

J.W. Morse  J. de Kanel  H.L. Craig Jr. 《Ocean Engineering》1979,6(3):297-315

An investigation has been made of available data on the saturation state of seawater with respect to calcium carbonate and its possible significance for scale formation on Ocean Thermal Energy Conversion (OTEC) heat exchangers. Pertinent oceanographic data is lacking at or near potential OTEC sites for the calculation of the degree of saturation of seawater with respect to calcium carbonate. Consequently, only “extrapolated” saturation values can be used. These indicate that near surface seawater is probably supersaturated, with respect to the calcium carbonate phases calcite and aragonite, at all potential OTEC sites. The deep seawater that would be brought to the surface at the potential Atlantic Ocean sites is also likely to be supersaturated with respect to calcium carbonate. The deep seawater at the potential Pacific Ocean sites may be slightly undersaturated.The fact that OTEC heat exchangers will be operating in seawater, which is supersaturated with respect to calcium carbonate, means that if nucleation of calcite or aragonite occurs on the heat exchanger surfaces, significant growth rates of calcium carbonate scale may be expected. The potential for calcium carbonate nucleation is highest at cathodic metal surface locations, which are produced as the result of aluminum corrosion in seawater. Consequently, corrosion and scale formation may be closely related. What the possible effects of biofouling may be on this process are not known.  相似文献   

Research challenges at the land–sea interface     

Drew M. Talley  Elizabeth W. North  Andrew R. Juhl  David A. Timothy  Daniel Conde  Jody F. C. deBrouwer  Cheryl A. Brown  Linda M. Campbell  Tobias Garstecki  Catherine J. Hall  Filip J. R. Meysman  David M. Nemerson  Pedro W. Souza Filho  Robert J. Wood 《Estuarine, Coastal and Shelf Science》2003,58(4):699

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Diel variations in the vertical distribution of copepods off the north coast of Spain   总被引：1，自引：0，他引：1  

de Puelles  M. L. Fernandez; Valdes  L.; Varela  M.; Alvarez-Ossorio  M. T.; Halliday  N. 《ICES Journal of Marine Science》1996,53(1):97-106

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Annual Cycle of Zooplankton Biomass, Abundance and Species Composition in the Neritic Area of the Balearic Sea, Western Mediterranean   总被引：7，自引：0，他引：7  

MªLuz Fernández de  Puelles  David Grás  & Santiago Hernández-León 《Marine Ecology》2003,24(2):123-139

Abstract. Seasonal changes in zooplankton biomass, abundance and species composition were studied at a neritic station in the Balearic Sea between April 1993 and May 1994. Sampling was carried out every 10 days in a zone influenced by the main current circulating through the Mallorca channel. Three main peaks of zooplankton biomass and abundance were observed: (1) at the beginning of summer when the thermocline developed, (2) in autumn when the thermocline broke down, and (3) in early spring. The smaller zooplankton fraction (100–250 μm) comprised on average 32 % of the total biomass and 73 % of total abundance. Copepods were the predominant group (64 % of the total abundance) with Clausocalanus, Oithona and Paracalanus being the most abundant genera. Paracalanus parvus, Clausocalanus furcatus, Acartia clausi, Oithona plumifera, Temora stylifera, Centropages typicus and Oncaea mediterranea were found to be the most important species in the area. Other abundant groups were cladocerans (15 %) and meroplankton larvae (12 %), both of which were particularly numerous during the stratified period. The copepod community was characterized by the above‐cited perennial species, which were abundant during the cycle studied. However, the influence of the hydrological conditions of the Balearic Sea, such as the Atlantic water influx and the physical structure of the water column (stratification and mixing), promoted the observed variability in zooplankton as well as the appearance of characteristic species during the annual cycle.  相似文献   

Further observations on the effects of preservation in 4% neutral formalin on the length and weight of 0-group flatfish     

Lockwood  Stephen J.; Daly  C. de B. 《ICES Journal of Marine Science》1975,36(2):170-175

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Temporal variation in an immune response gene (MHC I) in anadromous Salmo trutta in an Irish river before and during aquaculture activities     

Coughlan  James; McGinnity  Philip; O'Farrell  Brian; Dillane  Eileen; Diserud  Ola; de Eyto  Elvira; Farrell  Killian; Whelan  Ken; Stet  Rene J.M.; Cross  Thomas F. 《ICES Journal of Marine Science》2006,63(7):1248-1255

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Equilibrium constants of triethanolamine in major seawater salts     

I. Brandariz  P. Castro  M. Montes  F. Penedo  M.E. Sastre de Vicente 《Marine Chemistry》2006,102(3-4):291-299

Acid–base equilibrium constants of triethanolamine (TEA) have been determined by potentiometric titrations with a glass electrode, at 25 °C. Ionic strength was kept constant with only one electrolyte (using one of these salts: NaCl, KCl, MgCl₂ or CaCl₂), with binary mixtures of MgCl₂ and CaCl₂, and finally, in a solution with a composition approximately similar to that of natural seawater without sulfate. Equilibrium constants have been expressed in function of ionic strength by means of Pitzer equations and interaction parameters proposed in this theory have been obtained. It has been found that acid–base behaviour of TEA depends greatly on the salt used: basicity of TEA is decreased by CaCl₂, while it is increased by the other electrolytes used in this work.  相似文献   

United Nations global conference on the sustainable development of Small Island Developing States     

Charlotte de Fontaubert 《Ocean & Coastal Management》1994,24(3)

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Oxidative stress in Laeonereis acuta (Polychaeta, Nereididae): environmental and seasonal effects     

Geracitano LA  Monserrat JM  Bianchini A 《Marine environmental research》2004,58(2-5):625-630

Laeonereis acuta was seasonally collected in an industrially polluted site (P) and in an unpolluted site (UP) at the Patos Lagoon estuary (southern Brazil). Glutathione S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT) activity (U/mg protein) was determined in five groups of worms from each site. Metallothionein (MT - mol GSH/g ww) and lipid peroxides content (LPO - nmoles of cumene hydroperoxide/g ww) were also measured. Annual mean values for CAT (UP=3.7+/-0.3; P=5.7+/-0.6), GST (UP=0.034+/-0.003; P=0.045+/-0.004) and MT (UP=0.15+/-0.02; P=0.23+/-0.03) were higher (p<0.05) in worms from the P site. In autumn, CAT activity was higher (p<0.05) in worms from the P site (7.6 +/- 1.3) than in those from the UP site (3.6 +/- 0.4). In summer, MT concentration was higher in worms from the P site (0.37 +/- 0.03) than in those from the UP site (0.19 +/- 0.01). No significant difference (p>0.05) in the LPO content was observed in worms from the different sites or collected in different seasons. These results indicate that worms from the polluted site showed higher antioxidant responses than those from the unpolluted site, sufficient to prevent oxidative damage in terms of LPO.  相似文献   

Zooplankton variability and climatic anomalies from 1994 to 2001 in the Balearic Sea (Western Mediterranean)     

Fernandez de Puelles  M. Luz; Valencia  Joaquin; Vicente  Laura 《ICES Journal of Marine Science》2004,61(4):492-500

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