Salinity, saline

As it shrank, the lake became more saline. Salinity has almost doubled from 50 000 mg kg-1 in 1940 to about 90 000 mg kg-1 in recent years. The change in the lake s chemistry threatens to damage a unique ecosystem that supports large flocks of migratory waterfowl. 

Rats have also been trained to recognise the interoceptive cue produced by the administration of 3.0mg kg mecamylamine 15min before testing, with nicotine administered 120 min before testing (referred to as nicotine mecamylamine discrimination) from saline saline administration. In generalisation tests, mecamy-... 

Seawater contains about 3.5% salts, in which the content of sodium chloride is about 80%. The concentration of dissolved salts as well as temperature and pressure influence the physical properties of seawater. The total salt concentration is usually called salinity . Salinity is generally measured by the electrical conductivity or determination of chloride content. At present, salinity(S) is defined as S = 1.80655 Cl (Cl is the concentration of chloride in seawater) [5]. Dissolved oxygen and silica are usually measured as additional parameters to characterize seawater. The concentrations of nitrogen and phosphorus are the indices of nutrients and measure the fertility and production of the oceans. 

Table 3.1 also shows that Cb is the dominant ion in both formation water and injection water. Sometimes, we may use the amount of Cb to represent the salinity. Salinity effects are very important in alkaline flooding. This concept could be better understood after a discussion of alkaline flooding (see Example 10.4). 

Salinity Salinity plays at least two important roles, namely it maintains the integrity of the reservoir and it balances the physicochemical environment so that surfactant formulation stays close to optimal. Thus, ultra-low interfacial tension and oil solubilisation are very sensitive to salinity. Mixing of the surfactant slug with connate water may alter the surfactant formulation mainly due to dilution and to the incorporation of new electrolytes to the formula. Adsorption and desorption of electrolytes, particularly divalent cations, onto or from solid materials such as clay, will also change the salinity of the aqueous phases to some extent and may cause surfactant precipitation, which is however not always an adverse effect [151]. In order to attenuate the undesirable salinity effects on formulation, surfactants able to tolerate salinity changes [109], high salinity [150] and the presence of divalent ions [112] maybe used. 

Temperature, however, is not the only consideration ocean-water density is also influenced by salinity. Seawater contains dissolved ions, mainly sodium and chlorine, and, as a result, is denser than freshwater (typically 1035 kg m 3 compared with 1000 kg m-3). The salinity of seawater is not uniform everywhere in the ocean. Evaporation at the sea surface increases the salinity (as water is evaporated off but dissolved ions are left behind), whereas inputs from rain or river runoff lead to decreased salinity. Salinity is also increased by the formation of sea ice as ice forms, salt is rejected from the freezing water, and the remaining liquid water is enriched in salt. 

Salinity. Salinity was defined, in 1902, as the total amount of solid material (in grams) contained in one kilogram of seawater when all halides have been replaced by the equivalent of chloride, when all the carbonate... 

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