Forming , solid-phase

Lorsbach B. A., Kurth M. J. Carhon-Carhon Bond Forming Solid-Phase Reactions Chem. Rev. (Washington, D. C.) 1999 99 1549-1581... 

Fig. 2.23 Discharge curves for typical cathodic half-cells, (a) Reactants and products in solution phase, e,g, Fe3 (aq) and Fe2+(aq) (b) reactants and products both form solid phases, e,g. Ag20(s) and Ag(s)...

Total thiamine Baby food cereals cookies Acid hydrolysis with 0.1 M hydrochloric acid at 100°C for 30 min enzymatic hydrolysis of thiamine phosphates to thiamine with takadiastase at 47°C for 3 h weak ion-exchange (methyl-carboxylatein, add form) solid-phase extraction/ cleanup Analytical Lichrospher 100RP-18 (125 X 4 mm, 5 /u.m Merck ). Isocratic methanol + 10 mM phosphate buffer, pH 2.8 containing 5 mM sodium hexane-sulphonate + tri-ethylamine (15 + 84.9 + 0.1, v/v/v). 1.0 ml/min. UV absorbance 254 nm. External standardization. 79 Linear range = LoD to 7 /zg/ml thiamine, r = 0.9995. Reproducibility CV < 3% using food samples (n = 10). Recoveries 92.1-96.0% thiamine using baby food (n = 3). Samples spiked before hydrolysis. 

The only compounds in Table 3.2 that do not form solid phases within our model are Mg(NOs)2 and Ca(NOs)2. On Earth, common nitrate salts such an NaNC>3 and KNO3 typically form in arid, alkaline environments. Under these environmental conditions, Mg and Ca concentrations are low because of the insolubility of their respective carbonate minerals. Mg(N03)2 and Ca(N03)2 Pitzer-equation parameters were added to the model to account for trace concentrations of Mg and Ca in such nitrate environments. It would be a serious misuse of the model to calculate solution properties in systems where Mg(NC>3)2 and Ca(N03)2 are present at high concentrations. 

Patel, D. D., Koopmann, W., Imai, T., Whichard, L. P., Yoshie, O., and Krangel, M. S. (2001). Chemokines have diverse abilities to form solid phase gradients. Clin. Immunol. 99, 43-52. 

Especially with organics, which create complex crystal lattices held together by relatively weak forces, the rate of addition of molecules to the forming solid phase can exceed the ability of these molecules to orient themselves properly. This can easily result in a partially or totally amorphous structure in the solid. The frequency of this event can be minimized by providing seed particles with the desired final lattice stnrcture. The authors suggest that seeded growth processes should be considered early in development. 

Lorsbach, B. A. and Kurth, M. J. Carbon—carbon bond forming solid-phase reactions. Chem. Rev. 99 1549-1581, 1999. 

Liquids form solid phases on crystallization which are denser than the liquid (with the exception of water), and hence the freezing points are raised by increases in pressure. It is essential to avoid solidification because it can prevent a reaction from occurring and because possible damage to equipment may result. The freezing pressures of some common organic solvents at 25 °C are given in Table 7.2. 

Carbon-carbon bond-forming solid-phase reactions 99CRV1549, 01CRV137. 

This discussion has brought attention to the potential presence of two classes of interphase transport conditions in solid state systems. Let us examine these for a moment from the perspective of forming solid phases under model conditions. 

Spinel structures C03O4 and C0AI2O4 were prepared from solution containing 10 mol dm cobalt(II) acetate, 10 mol dm aluminum chloride, and 10" mol dm potassium formate. After accelerated electron irradiation (120 kGy), and heating of formed solid phase at 600°C or higher, spinel structure was formed. Formation of solid solution of both spinels may be expected (Cuba et al. 2012b). 

The measure of concentration of the impurity in the liquid phase is given by the distribution coefficient k, defined as the ratio of concentration of impurity I in the just-forming solid phase to that in the liquid phase, i.e.,... 

The Krafft point (KP) of a surfactant plays a very important role in the formation of different phases. It is the temperature at which there is a sudden increase in the solubility of surfactants in water [10,11]. Below the KP, a surfactant forms solid phases, whereas the liquid phases are formed above the KP of the surfactant. In general, we can classify these phases into the following three groups ... 

There is plenty of information available in literature on liquid crystalline and isotropic phases of different surfactants, but the study of the solid phases is limited to only soaps [12-19]. The basic reason for the lack of solid phase studies of synthetic surfactants is their limited use in solid form. The low KP of these surfactants limits their use to liquid products. Owing to a relatively high KP, sodium cocoyl isethionate (SCI), alkyl glycerol ether sulfonate (AGES), and sodium cocoyl monoglyceride sulfate (CMOS) form solid phases at room temperature, but there is hardly any information available on these solid phases. 

Consider the chemical reaction between FeS2 in the powder form (solid phase) and O2 in the gas phase ... 

This means a very low T. For a soap solution, is near room temperature. Polymer soap forms solid phases at room temperature, giving curd stabilized by a hydrated layer. When a polymer particle is uniform in size, curd are of regular structurelike crystal developing rainbow colors [28a]. 

Since cryogenic nitrogen-removal systems typically operate at temperatures as low as 115 to 80K (-250° to -310°F) in their coldest sections, it is necessary to remove impurities which might form solid phases to very low levels. Gaseous components which require removal, with their freezing points and typical allowable concentrations, are listed in Table 16-18. Particulate impurities, such as dust from a molecular sieve unit and entrained compressor lubrication oil, must also be removed to a very low level to minimize fouling of extended surface heat exchangers. 

Secondary amides trans- form) (solid phase) 1570-1515 6.37-6.60 s w... 

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