W Water content

Starch annealing involves heating starches with sufficient hydration below their Tq to facilitate molecular mobility (Tester et ah, 2001). Annealing is defined as "a physical treatment that involves incubation of starch granules in excess (>60% w/w) or at intermediate (40-55% w/w) water content during a certain period of time at a temperature above the glass... 

Hydrolysis of parathion in a loessial semiarid soil was investigated by Nelson et al. (1982). They found that Arthrohacter sp. hydrolyzed parathion rapidly in sterilized, parathion-treated soil under aerobic conditions (20% w/w water content). This bacterium was isolated from a silty loam, sierozem soil of loessial semiarid origin (Gilat). It uses parathion or its hydrolysis product, p-nitrophenol, as the sole carbon source. However, when parathion hydrolysis causes the amount of p-nitrophenol to reach a concentration greater than 1 mM or if the concentration is greater than 1 mM in the case of a single application of p-nitrophenol, the hydrolysis product becomes noxious to the bacteria and their growth is inhibited. 

W = water content (in percent) p = vapor pressure of sample p = vapor pressure of water at same temperature... 

F - correction factor, unitless wM w - water content of sweet gas from the McKetta-Wehe chart, g/Sm3 or lb/MMCF... 

Moisture content lactose monohydrate contains approximately 5% w/w water of crystallization and normally has a range of 4.5-5.5% w/w water content. See Table II. Particle size distribution see Table III. 

In order to improve the resolution efficiency, i. e. to increase the yield of the less-soluble three-component diastereomeric salt without any deterioration in the diastereomeric purity, the effect of water in ethanol was examined for a range of 2-75% (w/w) water contents. Table 5.10 shows that the enantiomeric excess of the amine recovered from the less-soluble diastereomeric salt increased and then decreased with decreasing water content, until finally no crystal was obtained. This result indicates that the presence of water in a solvent is essential for the formation of the less-soluble diastereomeric salt and that the three-component salt could possibly deposit in a larger quantity from a solvent less polar than ethanol. On the basis of this consideration, less polar alcohols were used as solvents in the presence of a small amount of water (Table 5.11). When 2-butanol containing two moles of water was used as a solvent, the highest resolution efficiency was achieved. The diastereomeric salt crystals, obtained in all the systems shown in Table 5.11, contained an equimolar amount of water as a component. These results obviously show that water plays a very important role in the formation of stable diastereomeric salt crystals with satisfactory diastereomeric purity. The recrystaUization of the crude salt once from aqueous 2-butanol gave the diastereomeric three-component salt with diastereomeric purity of more than 95 %. The final product (S)-3-(methylamino)-l-(2-thienyl)propan-l-ol with more than 99.5% ee was obtained upon treatment of the recrystaUized salt with aqueous sodium hydroxide, followed by extraction with 2-butanol and crystallization from toluene [21]. 

The VLE diagram for methyl acetate/water (Fig. 16.30) shows that ordinary fractionation also cannot be used for separating very dry product from the azeotrope if a feed of, say, 2.5%w/w water content were achieved, since the value for a in this composition area is virtually unity. 

MD simulation may be ideally suited for unraveling molecular structures in amorphous solids that may lead to instability or favor crystalhzation of one polymorphic form over another. Xiang and Anderson [24b] recently conducted an MD simulation study of amorphous IMC assemblies containing 0.6% w/w water content to explore both structural properties (e.g., IMC hydrogen bonding patterns, distribution of various IMC conformations, and the nature of water-IMC interactions) as well as dynamic processes (e.g., relaxation processes within the IMC molecule, and water diffusion). To explore the entire conformational space by MD simulation, it was necessary to reduce the torsionM barrier for (j) from 29.0 to 8.0kcal/mol in order... 

Residue on evaporation % w/w Water content % w/w Nitrogen trichloride ppm... 

Fig. 2. A graph showing the Ig k w. water content relationship when the analytes 1-5 were eluted from a phase with embedded polar groups using different concentrations of acetonitrile in the mobile phase.

Ip = plasticity index w = water content Wp = liquid limit Wp = plastic limit... 

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