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Mineralization partial

Enzyme Production. P. sajor-caju, when grown in a nutrient-rich medium under aerated, agitated conditions, was able to mineralize partially 14C-DHP lignin, as shown in Figure 1 (25). [Pg.474]

Thus, existing minerals partially dissolve in the intergranular fluid with precipitation and growth of the new mineral taking place at the expense, both compositionally and spatially, of the existing minerals. [Pg.349]

An example of a carbonate formation is one in which 95% of the bulk mineralogy is calcium carbonate (CaCOj). The remaining 5% represents other sandstone minerals partially filling or lining natural fractures, the principal flow channels in need of stimulation. Acid injection in such a... [Pg.26]

To prepare the free sulphinic acid, dissolve some of the sodium salt in cold water and cautiously acidify with hydrochloric acid avoid an excess of mineral acid since it dissolves the sulphinic acid to a certain extent. The resulting p-tolueneaulphinic acid is difflcult to dry without partial conversion into the sulphonic acid and thiolsulphonic ester... [Pg.826]

The exchange resins 6nd application in (i) the purification of water (cation-exchange resin to remove salts, followed by anion-exchange resin to remove free mineral acids and carbonic acid), (ii) removal of inorganic impurities from organic substances, (iii) in the partial separation of amino acids, and (iv) as catalysts in organic reactions (e.g., esterification. Section 111,102, and cyanoethylation. Section VI,22). [Pg.1020]

Drying. In many cases, the high moisture content of young coals dictates significant drying (qv) before use. In some cases, partial removal of mineral matter, especially water-soluble species, is desirable. [Pg.155]

Hydrochloric acid [7647-01-0], which is formed as by-product from unreacted chloroacetic acid, is fed into an absorption column. After the addition of acid and alcohol is complete, the mixture is heated at reflux for 6—8 h, whereby the intermediate malonic acid ester monoamide is hydroly2ed to a dialkyl malonate. The pure ester is obtained from the mixture of cmde esters by extraction with ben2ene [71-43-2], toluene [108-88-3], or xylene [1330-20-7]. The organic phase is washed with dilute sodium hydroxide [1310-73-2] to remove small amounts of the monoester. The diester is then separated from solvent by distillation at atmospheric pressure, and the malonic ester obtained by redistillation under vacuum as a colorless Hquid with a minimum assay of 99%. The aqueous phase contains considerable amounts of mineral acid and salts and must be treated before being fed to the waste treatment plant. The process is suitable for both the dimethyl and diethyl esters. The yield based on sodium chloroacetate is 75—85%. Various low molecular mass hydrocarbons, some of them partially chlorinated, are formed as by-products. Although a relatively simple plant is sufficient for the reaction itself, a si2eable investment is required for treatment of the wastewater and exhaust gas. [Pg.467]

Minerals normally considered nonmagnetic may be rendered magnetic by elemental substitution of a small amount of a magnetic element in the crystal lattice. Magnetic properties may also be affected by partial alteration in weathering effects. [Pg.419]

Talc of metasedimentary origin is formed by hydrothermal alteration of a dolomitic host rock by a silica-containing fluid. This type of deposit is typical of Montana and AustraUa. It is usually quite pure with talc content of 90 to 98% and often very white as well. Dolomite [17069-72-6], CaMg(C02)2, is the most common accessory mineral. The fourth type is of metamorphic origin, where a siUcaceous dolostone is first converted to tremolite [14567-73-8] or actinohte [13768-00-8] and then partially converted to talc. The Balmat, New York, and Death Valley, California, deposits are of this type. Tremolite, dolomite, and serpentine are common accessory minerals. This type of talc deposit has a variable talc content (30—80%), but is usually white and often commercially exploited because of the properties of its accessory minerals rather than the talc. [Pg.299]

In an oversimplified way, it may be stated that acids of the volcanoes have reacted with the bases of the rocks the compositions of the ocean (which is at the fkst end pokit (pH = 8) of the titration of a strong acid with a carbonate) and the atmosphere (which with its 2 = 10 atm atm is nearly ki equdibrium with the ocean) reflect the proton balance of reaction 1. Oxidation and reduction are accompanied by proton release and proton consumption, respectively. In order to maintain charge balance, the production of electrons, e, must eventually be balanced by the production of. The redox potential of the steady-state system is given by the partial pressure of oxygen (0.2 atm). Furthermore, the dissolution of rocks and the precipitation of minerals are accompanied by consumption and release, respectively. [Pg.212]

The volume of the freshwater amounts to only one-thirtieth of the 1.25 x 10 km (300 x 10 mi ) of the water ia salty oceans. Approximately one-third of the freshwater exists permanently as snow and ice (3). A large portion of the remaining freshwater has infiltrated too far underground or is partially polluted with minerals and chemicals and therefore is not readily usable. The entire life system on the earth depends on the remaining freshwater sources therefore, it is essential to protect the quaUty of the available waters. [Pg.220]

At higher temperatures the stable form is valentinite, which consists of infinite double chains. The orthorhombic modification is metastable below 570 °C however, it is sufficientiy stable to exist as a mineral. Antimony trioxide melts in the absence of oxygen at 656°C and partially sublimes before reaching the boiling temperature, 1425°C. The vapor at 1500°C consists largely of Sb O molecules, but these dissociate at higher temperatures to form Sb202 molecules. [Pg.202]

On the other hand, it has been demonstrated that the addition of CO2 to greenhouses iacreases the growth rate of plants so that an iacrease ia the partial pressure of CO2 ia the air could stimulate plant growth making possible shorter growing seasons and iacreased consumption of carboa dioxide from the air. CO2 is also used ia water-treatmeat appHcatioas. Because it is significantly safer than mineral acids, it can be used to reduce the alkalinity of treated water. [Pg.20]


See other pages where Mineralization partial is mentioned: [Pg.138]    [Pg.70]    [Pg.146]    [Pg.553]    [Pg.479]    [Pg.6234]    [Pg.138]    [Pg.70]    [Pg.146]    [Pg.553]    [Pg.479]    [Pg.6234]    [Pg.25]    [Pg.26]    [Pg.83]    [Pg.472]    [Pg.48]    [Pg.33]    [Pg.143]    [Pg.325]    [Pg.187]    [Pg.200]    [Pg.243]    [Pg.198]    [Pg.437]    [Pg.437]    [Pg.151]    [Pg.332]    [Pg.132]    [Pg.277]    [Pg.493]    [Pg.501]    [Pg.28]    [Pg.25]    [Pg.419]    [Pg.13]    [Pg.361]    [Pg.56]    [Pg.212]    [Pg.399]    [Pg.345]    [Pg.198]   
See also in sourсe #XX -- [ Pg.521 , Pg.544 ]

See also in sourсe #XX -- [ Pg.83 ]




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