Glycol-water mixtures

Freezing point of propylene glycol-water mixtures ... 

It I. becomes too long, consider using glycol/water mixture or another heat medium liquid and raise the bath temperature above ]9U l i... 

Glycol/water mixture leaks from jacket into blender, reacts with aluminum powder and sodium hydrosulfite, and initiates exothermic decomposition No—N2 atmosphere, confinement in blender R NOAA Worksheet indicates combining sodium hydrosulfite with ethylene glycol is "explosive due to vigorous reaction or reaction products may produce detonation," "may cause fire," and indicates "flammable gas generation" and "heat generation by chemical reaction, may cause pressurization"... 

The various redox states of cytochrome P-450 (Fe ", Fe " " RH, Fe " " RH) as well as the metastable oxyferrous compound [(O2—Fe " ") RH] are obtained in ethylene glycol-water mixture their absorption spectra and formation rates are similar to those recorded in pure aqueous media. These identical spectra demonstrate that the intermediates obtained in the mixed solvent at normal and subzero temperatures are similar to those found in the productive enzyme pathway under normal conditions. This is an essential observation since the low-temperature procedure permits one to stabilize and accumulate intermediates and offers the opportunity of obtaining structural information about such intermediates—a result unattainable by classical fast-kinetic techniques. 

Dielectric Constant (D) and Freezing Point of Ethylene Glycol—Water Mixtures"... 

Errors quoted have been ignored for the sake of clarity, but typically amount to - 25%. Corrections for ionic effect in ethylene glycol—water mixtures have not been made (Buxton and Kemsley). 

The tunneling decay of et by reaction with acceptors at temperatures permitting diffusion of reagents has also been studied in a vitreous ethylene glycol-water mixture (70% ethylene glycol + 30% water) [105], The decay of et by reaction with H in the range 25-120 K is found to be well described by eqn. (35) of Chap. 4. At 140 K and above the decay of etr can be described... 

The condenser was cooled with an ethylene glycol-water mixture at —5°, and the receiver was cooled to —10° in an ice-salt bath. 

Yalkowsky, Rubino, and others [63-67] have further studied log-linear cosolvent solubilization. For organic solutes in propylene glycol-water mixtures, Yalkowsky and Rubino found that the following equation... 

Real experiments for the determination of external mass transfer coefficients are used as an example for virtual experiments with CFD. Here experimental studies (Williamson et al., 1963 Wilson and Geankopolis, 1966) on the flow of two liquids, namely water and a propylene glycol-water mixture, through a packed bed of spherical particles made from solid benzoic acid are... 

Wells (1975) has analysed transfer function in ethylene glycol + water mixtures and shown that H+ ions are stabilized and Cl- ions are destabilized when x2 increases, the curve for 5m/x (H+) having... 

Figure 56. Dependence of the thermodynamic properties of HC1 on co-solvent mole fraction in ethylene glycol + water mixtures at 298 K (Stern and Nobilione, 1968).

The dielectric constant of a solvent plays a significant role in solubility and stability of the solute. Few studies relating to the dielectric constant of the solvent medium to the photodegradation rate have been undertaken. Thoma and Klimek (8) reported that the improvement in the photostability of nifedipine noted by them is due to an increase in dielectric constant in both ethanol/water and propylene glycol/water mixtures. 

The test loop used in this experiment is made of two distinct circuits the main circuit with a refrigerant R134a flow where the test section is inserted and a secondary cooling circuit with a glycol-water mixture to cool the fluid heated in the test section (Figure 20). 

Additional studies indicated that a can be estimated for a solute in specific cosolvent-water combinations using the solute octanol-water partition coefficient, log P, as an index of solute polarity. Thus, for propylene glycol-water mixtures ° ... 

Yalkowsky, S.H. Rubino, J.T. Solubilization by cosolvents I organic solutes in propylene glycol-water mixtures. J. Pharm. Sci. 1985, 74 (4), 416-421. 

Fig. 6 Solubilization of different hydrocortisones in propylene glycol-water mixtures O, hydrocortisone acetate, hydrocortisone propionate, x, hydrocortisone butyrate, A. hydrocortisone pentanoate, g, hydrocortisone hexanoate, o, hydrocortisone heptanoate.

The analysis of the experimental solubilities of naphthalene in ethylene glycol-water mixtures at room temperature (Khossravi and Connors, 1992 Huot et al., 1991) showed that both experimental sets were accurate in a wide composition range with the exception of the points between Xetd 0.5 and 0.6 (Fig. 5). 

Huot, J.-Y., Page, M., Jolicoeur, C., 1991. Thermodynamicproperties of naphthalene and uric acid in ethylene glycol-water mixtures. J. Sol. Chem. 20, 1093-1112. 

Dielectric Constant of Ethylene Glycol-Water Mixtures ... 

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