Transition concentration, soluble

The transition concentration of cocrystal component can be predicted by substituting the single component crystal solubility, Sa, for the cocrystal solubility, S, in Eq. (7) and rearranging to give... 

A priori knowledge of the solubility of cocrystal in pure solvent is useful to predict the ligand transition concentration and to determine conditions under which cocrystals dissolve or cocrystallize. Fig. 20 shows... 

The dissolution rate of the drug substance can be calculated from the plot of the concentration of the drug substance as a function of time. Study of the dissolution of metastable polymorph may demonstrate the conversion from the P form to the a form. With the use of the initial rate prior to transition, the solubility of the jS form (which is difficult to determine by other means) can be calculated from the dissolution curve. 

Related stiutegies can also be used based on more complex compositions of the protein-based polymers. If, for example, the polypeptide contains a repeating ioniz-able function, instead of heating and cooling, a change of pH or salt concentration can be used to control the phase transition between soluble and insoluble states, and, thereby, to enable their separation from bacterial proteins by centrifugation. 

The reaction sequence (5)-(8) leads to the rapid accumulation of hydroperoxides and the attainment of a stationary peroxide concentration. Soluble Cu, Mn, Fe, Cr and Co compounds are the most effective promoters of peroxidation whereas Ni, Ce, V, Ti and Zn salts are less effective [16]. Transition metal ions are also photo-initiators of... 

The physical and chemical properties are less well known for transition metals than for the alkaU metal fluoroborates (Table 4). Most transition-metal fluoroborates are strongly hydrated coordination compounds and are difficult to dry without decomposition. Decomposition frequently occurs during the concentration of solutions for crysta11i2ation. The stabiUty of the metal fluorides accentuates this problem. Loss of HF because of hydrolysis makes the reaction proceed even more rapidly. Even with low temperature vacuum drying to partially solve the decomposition, the dry salt readily absorbs water. The crystalline soflds are generally soluble in water, alcohols, and ketones but only poorly soluble in hydrocarbons and halocarbons. 

In comparison with catalytic reactions in compressed CO2 alone, many transition metal complexes are much more soluble in ionic liquids without the need for special ligands. Moreover, the ionic liquid catalyst phase provides the potential to activate and tune the organometallic catalyst. Furthermore, product separation from the catalyst is now possible without exposure of the catalyst to changes of temperature, pressure, or substrate concentration. 

The presence of ether linkages in the polymer molecule imparts chain flexibility, lowers glass transition temperature, and enhances solubility while maintaining the desired high temperature characteristics [192]. Recently, polyether imines were prepared by the reaction of different diamines with 4,4 -[l,4-phenylene bis(oxy)] bisbenzaldehyde [184]. The polymers synthesized by the solution method were yellow to white in color and had inherent viscosities up to 0.59 dl/g in concentrated H2SO4. Some of these polyimines can be considered as... 

The alkali metals do not form intermetallic compounds with the transition metals. Both Na and Li dissolve only ppm quantities of most transition metals, although the solubilities are greater in Li. Nickel is very soluble in Li (900 ppm at 600°C), but no intermetallic compound forms. Intermetallic compound formation is, however, observed between Li and the noble metals Rh, Ir, Pd and Pt, so this section concentrates on the preparation of these compounds. 

The gel/sol transitions cannot be distinguished for pectins extracted by after acid treatment and water-soluble pectins after extrusion. A minimal pectin concentration of 0.2% is required for gelation and no gels can be obtained below a sucrose concentration of 45 %. Commercial pectin (Hercules) with a dm 73 % has a lower phase transition line with a minimal pectin concentration of 0.1 % and sucrose concentration of 40 %. 

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