Effects of mixture composition

FIG. 13-17 Effect of mixture composition upon K value for n-pentane at 104 C (220 F). K values are shown for various values of VP, weight fraction propane on a methane-free basis for the methane-propane-pentane system. [Hadden, Chem. Eng. Prog. Symp. Sec. 7, 49, 5S (1953).]... 

Application of DSC and HPLC to determine the effects of mixture composition and preparation during the evaluation of niclosamide-excipients compatibility showed that although some reactions occurred, niclosamide was compatible with a majority of common tablet excipients tested [63],... 

As the temperature of dilute aqueous solutions containing ethoxylated nonionic surfactants is increased, the solutions may turn cloudy at a certain temperature, called the cloud point. At or above the cloud point, the cloudy solution may separate into two isotropic phases, one concentrated in surfactant (coacervate phase) and the other containing a low concentration of surfactant (dilute phase). As an example of the importance of this phenomena, detergency is sometimes optimum just below the cloud point, but a reduction in the washing effect can occur above the cloud point (95). However, the phase separation can improve acidizing operations in oil reservoirs (96) For surfactant mixtures, of particular interest is the effect of mixture composition on the cloud point and the distribution of components between the two phases above the cloud point. 

Naiborodenko, Y. S., and Itin, V. I., Gasless combustion of mixtures of metal powders. II Effect of mixture composition of the combustion rate and the phase composition of the products. Combust. Explos. Shock Waves, 11,626 (1975b). 

Figure 3. Effect of mixture composition on positive ion concentrations in a non-sooting flame (26). Acetylene/oxygen pressure = 4 mm Hg.

There have been a number of measurements of the effects of mixture composition and temperature on the hydrogen—oxygen second limits in potassium chloride coated vessels (e.g. refs. 28,14, 23, 25, 30). Typical of the results are the explosion regions shown in Figs. 3 and 4. They all... 

We have studied the effects of mixture composition on droplet microstructure (5), and summarized these results in the form of a rich morphology diagram (Figure 3) in the parameter space of mass fraction and shear rate. Formation of strings of the suspended phase was observed over a broad composition window. At each composition, experiments were stopped when strings were formed. We also found a non-transient moiphology where we saw arrangement of the droplets in ordered pearl-necklace chain structures. 

Figure 33 demonstrates the effect of mixtures composition on the degree of crystallinity (k). 

Several such Charts have been developed in the past [Scheibel and Jenny, 1945 Winn (Hadden, 1953) DePriester, 1953]. They give the K values for several light hydrocarbons as functions of the temperature and pressure of the system only. The other components of the mature - and its composition - are not involved. Some average effect is included in the K values, however, since experimental data were used in their construction. In addition, considering the similarity of the compounds involved and the low pressures covered in the Charts, the effect of mixture composition should not be very significant away, of course, from its critical point. 

Fig. 2. Effect of mixture strength on exhaust gas composition (dry basis) and brake specific fuel consumption (BSFC) for an unsupercharged automotive-type engine usiag iadolene fuel, H/C = 1.86, where the ignition is tuned to achieve maximum best torque (MBT), the brake mean effective...

It is seen that the curves in Figure (24) become horizontal between 40°C and 45 °C as predicted by the theory. It is also clear that there is likely source of error when exploring the effect of solvent composition on retention and selectivity. It would be important when evaluating the effect of solvent composition on selectivity to do so over a range of temperatures. This would ensure that the true effect of solvent composition on selectivity was accurately disclosed. If the evaluation were carried out at or close to the temperature where the separation ratio remains constant and independent of solvent composition, the potential advantages that could be gained from an optimized solvent mixture would never be realized. 

Thermodynamics is the branch of science dealing with the energetics of substances and processes. It describes the tendency of processes to take place spontaneously, the effects of external conditions, and the effects of the composition of mixtures on such processes. Thermodynamics is generally capable of correlat-... 

The solvent-mediated transformation of o -L-glutamic acid to the S-form was quantitatively monitored over time at a series of temperatures [248]. The calibration model was built using dry physical mixtures of the forms, but still successfully predicted composition in suspension samples. Cornel et al. monitored the solute concentration and the solvent-mediated solid-state transformation of L-glutamic acid simultaneously [249]. However, the authors note that multivariate analysis was required to achieve this. Additionally, they caution that it was necessary to experimentally evaluate the effect of solid composition, suspension density, solute concentration, particle size and distribution, particle shape, and temperature on the Raman spectra during calibration in order to have confidence in the quantitative results. This can be a substantial experi-... 

The effect of solvent composition on the retention of a series of solutes, commonly used to measure column dead volumes, was also investigated by these authors. They employed mixtures of methanol and water as the mobile phase and measured the retention volume of the same salts together with a silica gel dispersion (containing particles 0.002 micron in diameter). They also measured the retention volume of the components of the mobile phase methanol, and water. The silica dispersion was chosen to simulate a solute of very large molecular size. The results they obtained are shown in figure (2). 

Although glycosphingolipids are the specific lipid components in the antigen-antibody complex, their activity is markedly enhanced by other (auxiliary) lipids such as lecithin and lecithin-cholesterol mixtures (15). The present study deals with the effect of lipid composition on the penetration of lactoside—cholesterol and lactoside—lecithin monolayers by rabbit y-globulin. We also investigated the lecithin-cholesterol system. Furthemore, since criteria for the existence of lipid-lipid complexes in monolayers are still few (8, 17), we have used infrared spectroscopy to examine lipid mixtures for the presence of complexes. 

Lunge et al. [15] examined the effect of the composition of mixed add, and the influence of the nitration temperature within the range from 0 to 80°C on the nitrogen content of nitrocellulose, the content of non-nitrated cellulose, the yield, the solubility of the products in ether-alcohol mixture and the viscosity of the acetone solution. Cotton linters were used. From these experiments it has been established that nitrocellulose containing more than 13.5% N is unstable and decomposed readily, as mentioned before. 

Plattner (82) briefly examined the effects of solvent composition upon TG separations. Mixtures of acetone/methanol and acetone/acetonitrile were examined. In this work, acetone/ acetonitrile mobile phases were reported to give less complex chromatograms of TG mixtures than acetone/methanol mixtures. 

Pauls (83) examined the effect of the composition of binary solvent mixtures upon the selectivity and resolution of olive oil TG components. Separation factors (a values) and resolution were calculated for the linoleyldiolein (LOO)-linoleyl-palmitylolein (LPO) and triolein (OOO)-palmityldiolein (POO) pairs in olive oil. Five strong solvents (isopropanol, dichloromethane, chloroform, tetrahydrofuran, and acetone) as well as two weak solvents (methanol and acetonitrile) were employed. 

Effect of the composition of the starting mixture on the molecular weight of the products... 

Table II lists the feed gas compositions used for the study to determine the effects of feed composition on membrane performance. The different compositions are representative of diving gas mixtures used at various depths. Both the individual component permeabilities and the mixture permeabilities were evaluated at several different pressure drops up to 1200 psig feed pressure.

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