Environment brackish

Silver reduces the oxygen evolution potential at the anode, which reduces the rate of corrosion and decreases lead contamination of the cathode. Lead—antimony—silver alloy anodes are used for the production of thin copper foil for use in electronics. Lead—silver (2 wt %), lead—silver (1 wt %)—tin (1 wt %), and lead—antimony (6 wt %)—silver (1—2 wt %) alloys ate used as anodes in cathodic protection of steel pipes and stmctures in fresh, brackish, or seawater. The lead dioxide layer is not only conductive, but also resists decomposition in chloride environments. Silver-free alloys rapidly become passivated and scale badly in seawater. Silver is also added to the positive grids of lead—acid batteries in small amounts (0.005—0.05 wt %) to reduce the rate of corrosion. 

In oil and gas refinery appHcations, titanium is used as protection in environments of H2S, SO2, CO2, NH, caustic solutions, steam, and cooling water. It is used in heat-exchanger condensers for the fractional condensation of cmde hydrocarbons, NH, propane, and desulfurization products using seawater or brackish water for cooling. 

Environment Tube side Brackish, estuarine water (polluted), 2-3 ppm tolyltriazole residual, ferrous sulfate 1 ppm as iron for 2 months for 1 hr/day, dispersant 5-8 ppm... 

Environment Internal Brackish water treated with toiyitriazole and a chlorine biocide External Steam and condensate... 

Environment Tube side 60-80°F (16-27°C), pH 8.3-8.7 treatment— tolyltriazole, dispersant brackish water... 

Most of the published evidence suggests that marine fouling cover— particularly where it is continuous and well established — reduces corrosion rates of steels . Indeed, 35%o seawater is by no means the most corrosive of saline environments towards steel. Brackish water, as found in estuarine or certain other coastal areas, is considerably more aggressive towards steel, and careful design measures should be taken to ensure that effective corrosion control is achieved in such circumstances. 

Kari, T. and P. Kauranen. 1978. Mercury and selenium contents of seals from fresh and brackish water in Finland. Bull. Environ. Contam. Toxicol. 19 273-280. 

Also irrigation with brackish and saline waters is actively explored, with teams studying plant response to irrigation at various salinity levels and implications on the soil and the environment (e.g. INCO-DC 2001 DRC 2002). Results so far achieved show that unsuspected possibilities are open for the use of large, till now neglected unconventional water resources and that traditional guidelines based on crop salinity... 

Snell, T, and Persoone, G. Acute toxicity bioassays using rotifers. I. A test for brackish and marine environments with... 

Mobilization of arsenic can be promoted by the presence of other solutes and their interaction with arsenic to form complexes, as detailed above for NOM. As(V) has been documented to form complexes with calcium and magnesium in brackish water and seawater (Cullen and Reimer, 1989). Arsenic commonly forms complexes with sulfide, such as As3S3(SH)3° (Bostick, Fendorf and Manning, 2003) (Chapter 3). These complexes may exist in slightly sulfidic environments. Arsenic-fluoride complexes (e.g. AsC F2-and HAsC F-) can also form in high-fluoride waters ((Apambire and Hess, 2000 Bundschuh, Bonorino and Viero, 2000), Chapter 3). 

The AP concentrations in sediments were also greater in creeks than in the brackish and marine environment. The average concentrations of NP, OP, and BP in sediment from Lake Shihwa were 609, 18, and 10 ng g-1 dw, respectively (Khim et al., 1999a). The NP concentration was detected up to 116700 ng g-1 dw in suspended solids, and 32000 n g-1 dw in sediments. The concentrations of APs and BPA in soil samples from the national monitoring sites of NIER were at a few ppb levels, implying that little APs and BPA were introduced into soil. 

The general objective, principle, and scope of application of the pT-method are succinctly described in Section 1 and also reported elsewhere in this book (see Chapter 3 of this volume, Section 5.1), where readers will appreciate that this hazard assessment scheme is adaptable to both liquid and solid media. Briefly recalled here in the context of solid-media samples such as dredged material, the pT-value, which relates to a single bioassay, and the pT-index, derived from the most sensitive organism in a test battery, permit a numerical classification of environmental samples on the basis of ecotoxicological principles. Sediment from any aquatic ecosystem (freshwater, brackish, marine) and from any of its phases (whole sediment, porewaters, elutriates or organic extracts) can be appraised provided that the proper standardized toxicity tests are available. There are whole-sediment test protocols standardized for many agencies (e.g., Environment Canada, ASTM). 

Meyerson, L.A., Saltonstall, K., Windham, L., Kiviat, E., and Findlay, S.E.G. (2000) A comparison of Phragmites australis in freshwater and brackish marsh environments in North America. Wetlands Ecol. Manag. 8, 89-103. 

On the Caucasian coast, the Old Euxinian deposits form a thin accumulative cover of one or two marine terraces. The deposits are coarse-grained and sandy-pebbly they refer to a dynamic near-shore sedimentation environment. On the Bulgarian shelf and in estuarine parts of river valleys, the Old Euxinian deposits are characterized by a fine-grained lithological composition and, in addition to the Black Sea and Caspian brackish-water fauna, contain numerous shells of the fresh-water species Dreissena polymor-pha. 

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