Brines highly evolved

In both cases, the CaCb-rich brine is thought to have evolved from the NaCI-rich brine after fluid-rock interactions in the basement. The fault zones and the breccia bodies at the base of the basins represent active drainage zones where different fluid reservoirs were connected, and thus a highly favourable location for fluid mixing. Temperature and pressure changes, combined with the effects of fluid mixing, appear to be key-factors in the main stages of quartz cementation and U deposition in both Australian and... 

A mixed gas of 60-75 percent C02 derived from mixing the 40 percent C02 from the kilns and the 90 percent C02 from the calcinations of bicarbonate, is fed to the bottom of these crystallizing units. Absorption of C02 in the highly alkaline ammoniated brine results in crystallization of crude sodium bicarbonate. Because of the heat evolved in the absorption and neutralization of the carbonic acid gas and from crystallization of the sodium bicarbonate, the temperature of the liquor in the column rises from 38°C to a maximum of about 62-64°C. In normal operation, the temperature of the discharge slurry is maintained at about 27°C by automatic adjustment of the water flow through the cooling tubes. A tower such as that shown in Fig. 26.2 has a capacity for producing 50 tons per day of finished soda. 

Model 2. If water, no matter what its original salinity, was in near equilibrium with calcite + dolomite or was oversaturated with dolomite by virtue of a high Mg/Ca ratio at shallow depth (like Cretaceous seawater or a sabkha brine), it could never evolve to its present composition with increasing temperature (burial) by dolomitization because the water is everywhere undersaturated with dolomite today. It is very unlikely that the very low Mg/Ca ratio of the brine could be primary because neither Cretaceous seawater nor any reasonable Cretaceous sabkha brine are likely to have had such a composition. 

Importantly, salt-induced peptide formation could provide an abiotic route for the formation of peptides directly from amino acids in concentrated NaCl solutions containing copper ions. Montmorillonite and similar minerals apparently promote the condensation reaction that could have taken place in evaporating tidal pools -Darwin s warm little ponds - where the required salty brine solutions were easily available. Obviously, this is a likely and hence a credible prebiotic scenario. There might a pearl hidden beneath muddy waters. Besides, it is fascinating to assume that the primitive enolase enzyme known to be a highly conserved ancient enzyme could have evolved in an RNA-peptide world. Enolase catalyzes the for enantio-selective carbon-carbon bond addition of water to phosphoenol pyruvate to yield D-2-phospho-glycerate. 

Types of Process Equipment. Nitrations, as technical industrial processes, have evolved from batch-type operations using stoneware vessels and hand operations to automatically controlled continuous-type processes carried out in gleaming stainless-steel vessels. The high heats of reaction and dilution involved in nitration, originally absorbed by placing the stoneware vessels in a water bath, are now taken up by coils or jackets cooled by refrigerated brine. Controls have evolved from none at all to completely automatic,systems which may be so elaborate as to permit operation from remote locations. The idea of remote control has always appealed to the designer of equipment for the manufacture of hazardous, explosive compounds which often are the result of nitration processes. 

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