Salinities

Salinity occurs in coastal areas affected by seawater, in areas receiving salty water by lateral flow from salt-bearing rocks upstream, and also in otherwise non-saline environments as a result of soil waterlogging, mainly due to high ground water. In waterlogged land, whatever dissolved salt is brought in with the 

Salinity affects microbial activity, in part, because it controls water availability. The higher the salinity, the more energy an organism must expend to maintain a favorable osmotic balance. Salts, of course, have effects on living organisms beyond water availability. For example, salts can be both a source of essential nutrients as well as a source of toxic heavy metals. Also, sulfate salts appear to be more favorable for life than chloride salts see the discussion in Sect. 5.1.2 (Aqueous Saline Environments). However, in this section on salinity, the focus will be on salinity as a control on water availability. 

This diversity of measures of salinity is especially a problem in cross-disciplinary work, where alternative measures from other disciplines are often unfamiliar. The equations needed to convert from one measure to another are 

There are fewer studies of high alkalinities (pH 10) than of high acidities (pH 1.0) probably because high alkalinities are more rare in nature. Nevertheless, there are reports of organisms tolerating pH values 11 (Table 4.3), and maybe even as high as 12.5-13 (Bachofen 1986 Duckworth et al. 1996). 

The mineral concentrations in the blood plasma of the primitive cyclostomes (hagfish and lampreys) are close to those of the surrounding sea water (Robertson, 1954 McFarland and Munz, 1958 Bellamy and Chester Jones, 1961). More evolutionarily advanced species maintain relatively lower internal concentrations, presumably because the tissues function best under 

The major ions in different organs and body fluids of euryhaline fish have been studied by a number of authors. The concentrations of sodium, potassium, magnesium and chloride were usually more concentrated in fish taken from sea water than in those from fresh water, the effect being shown in blood, kidney, liver, various secondary muscles and urine. The trend was less clear in the case of swimming muscle, as were the values for calcium (reviewed by Love, 1970, Table 30). All the ions mentioned above were much more concentrated in the urine of the fish from the sea, urine being one channel by which these salts are excreted. A fish with remarkable ability to control its internal milieu is the tilapia, in which the total sodium in the body increases by only 30% when it is transferred from fresh water to doublestrength sea water (Potts et al., 1967). 

Most species of fish can tolerate only small changes in external salinity, when they are said to be stenohaline, and they will swell up and die if transferred from sea water to fresh water. If the transfer is in the other direction, they die because the large influx of salt exceeds the level at which the tissues can function. However, Hulet et al. (1967) found that, in the presence of increased concentrations of calcium, permanently marine fish could thrive in a much-diluted medium. 

The kidneys are not the only channel through which excess salts are eliminated from the blood. Motais et al. (1965) reported that, when flounders, which are euryhaline, were transferred from sea water to fresh water, there was an immediate reduction in the elimination of sodium and chloride by a mechanism located in the gills. The painted comber, a species which dies if the 

It has been calculated that, at a salinity of 30%o, nearly one-third of the energy consumed by a fish is used for osmoregulation (Farmer and Beamish, 1969 Rao, 1969). It follows that an excess of any other activity, or a situation where energy is consumed is likely to affect the ability of a fish to osmoregulate. This proves to be the case, and is immensely important in biochemical ecology. The 

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Data gathering in the water column should not be overlooked at the appraisal stage of the field life. Assessing the size and flow properties of the aquifer are essential in predicting the pressure support which may be provided. Sampling of the formation water is necessary to assess the salinity of the water for use in the determination of hydrocarbon saturations. 

Formation water density is a function of its salinity (which ranges from 0 to 300,000 ppm), amount of dissolved gas, and the reservoir temperature and pressure. As pressure increases, so does water density, though the compressibility is small... 

Vapour Pressure Base Sed. and Water Teperature Salinity... 

One of the primary objectives of production operations is to deliver product at the required rate and quality. Therefore the product quality specification and any agreed contract terms will drive the activities of the production operations department, and will be a starting point for determining the preferred mode of operation. The specifications, such as delivery of stabilised crude with a BS W of less than 0.5%, and a salinity of 70 g/m, ... 

Hydrocarbon-water contact movement in the reservoir may be determined from the open hole logs of new wells drilled after the beginning of production, or from a thermal decay time (TDT) log run in an existing cased production well. The TDT is able to differentiate between hydrocarbons and saline water by measuring the thermal decay time of neutrons pulsed into the formation from a source in the tool. By running the TDT tool in the same well at intervals of say one or two years (time lapse TDTs), the rate of movement of the hydrocarbon-water contact can be tracked. This is useful in determining the displacement in the reservoir, as well as the encroachment of an aquifer. 

Cationic surfactants may be used [94] and the effect of salinity and valence of electrolyte on charged systems has been investigated [95-98]. The phospholipid lecithin can also produce microemulsions when combined with an alcohol cosolvent [99]. Microemulsions formed with a double-tailed surfactant such as Aerosol OT (AOT) do not require a cosurfactant for stability (see, for instance. Refs. 100, 101). Morphological hysteresis has been observed in the inversion process and the formation of stable mixtures of microemulsion indicated [102]. 

Fig. XV-9. Fluorescence micrograph of the stripe patterns observed in a monolayer from a mixture of PA and SP-Bi-25 (20% by weight peptide) on a buffered saline subphase at 16 C and zero surface pressure. (From Ref. 55.)...

Maroudas N G 1977 Sulphonated polystyrene as an optimal substratum for the adhesion and spreading of mesenohymal sells in monovalent and divalent saline solutions J. Cell. Physiol. 90 511-20... 

P. E. Smith and B. M. Pettitt. Amino acid side-chain populations in aqueous and saline solution Bis(penicillamine) enkephalin. Biopolymers, 32 1623-1629,... 

If poUed, most aquaculturists would probably indicate a preference for well water. Both freshwater and saline wells are common sources of water for aquaculture. The most commonly used pretreatments of well water include temperature alteration (either heating or cooling) aeration to add oxygen or to remove or oxidize such substances as carbon dioxide, hydrogen sulfide, and iron and increasing salinity (in mariculture systems). Pretreatment may also include adjusting pH, hardness, and alkalinity through the appHcation of appropriate chemicals. 

Another example is dissolved oxygen (DO). The amount of DO water can hold at saturation is affected by both temperature and salinity. The warmer and/or saline the water, the lower the saturation DO level. Oxygen saturation is also affected by atmospheric pressure. The saturation oxygen level decreases as elevation increases. 

Adsorption of t-PA to process equipment surfaces consisting of either stainless steel or glass was minimized by adding the detergent polyoxyethylene sorbitan monooleate (Tween 80) to the semm-free culture conditioned media at 0.01% (vol/vol). The equipment was also rinsed, before use, with phosphate buffered saline (PBS) containing 0.01% Tween 80. Hydrophilic, plastic equipment was used whenever possible. AH buffers were sterile filtered. Sterile filtration of Hquids and gases is usually carried out using 0.2 or 0.45 p.m filters. 

DI = deionized water PBS, phosphate-buffered saline HSA, human semm albumin essential medium + 10% fetal bovine semm. 

Fig. 5. Lower and upper critical tielines in a quaternary system at different temperatures and a plot of the critical end point salinities vs temperature, illustrating lower critical endline, upper critical endline, optimal line, and tricritical poiat for four-dimensional amphiphile—oil—water—electrolyte-temperature...

Eigure 6 illustrates how the three tensions among the top, middle, and bottom phases depend on temperature for a system of nonionic surfactant—oil—water (38), or on salinity for a representative system of anionic surfactant—cosurfactant—oil—water and electrolyte (39). As T approaches from lower temperatures, the composition of M approaches the composition of T, and the iaterfacial teasioa betweea them, goes to 2ero at T =. ... 

The temperature (or salinity) at which = o mt called the optimal temperature (or optimal salinity), because at that temperature (or salinity) the... 

The basic Solvay process remains the dominant production route for soda ash. Its continued success is based on the raw matedals, salt and limestone, being more readily available than natural alkaU. AH soda ash processes are based on the manipulation of saline phase chemistry (6,7) an understanding of which is important both to improving current processes and to the economic development of new alkaU resources. 

J. J. Eahey, Saline Minerals of the Green PiverFormation, Geological Survey Professional Paper 405, U.S. Government Printing Office, Washington D.C., 1962. 

Sodium Bicarbonate. Sodium bicarbonate [144-55-8] NaHCO, is a white crystalline powder. It is odorless, has a saline and shghdy alkaline taste, and is stable in dry air, but slowly decomposes in moist air. Its solubihty is one gram in 10 mL water in hot water it is converted into carbonate, and it is insoluble in alcohol. 

Magnesium sulfate heptahydrate may be prepared by neutralization of sulfuric acid with magnesium carbonate or oxide, or it can be obtained directly from natural sources. It occurs abundantly as a double salt and can also be obtained from the magnesium salts that occur in brines used for the extraction of bromine (qv). The brine is treated with calcium hydroxide to precipitate magnesium hydroxide. Sulfur dioxide and air are passed through the suspension to yield magnesium sulfate (see Chemicals frombrine). Magnesium sulfate is a saline cathartic. 

A(jua.tlC Pollution. Aquatic pollution is of some concern from hydrothermal resources. The primary problem is the disposal of highly saline fluids from water-dominated reservoirs. This is generally overcome by pumping into deep reservoirs situated well beneath potable water sources. The fluid... 

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