Ideal solution volume increment

Let us now examine the assumptions underljdng the Oncley treatment. First, thermodynamically V is defined as the increment of the volume of the solution per unit mass of the solute added and therefore is not identical with Fsp of the solute. These two quantities may be equal in magnitude if and only if the system is an ideal solution, that is, there is no solute-solvent interaction whatsoever present. To eliminate one unknown Fsp in Eq. (14) by introducing F we have at the same time added another uncertain term w into the equation. Thus this treatment offers at most a rough estimate of the shape of proteins for a chosen model, a prolate or an oblate ellipsoid. Furthermore the estimated p value corresponds only to the hydrated particle, which is slightly different from that of the unhydrated particle unless the bound water is so distributed throughout the protein molecule that it does not change its axial ratio because of hydration. 

We next consider the heat of solution and volume increment of solution for the case of ideal solutions. The partial molal enthalpy of component i is given by Eq. (7-142) in the form... 

The analysis of mixed associations by light scattering and sedimentation equilibrium experiments has been restricted so far to ideal, dilute solutions. Also it has been necessary to assume that the refractive index increments as well as the partial specific volumes of the associating species are equal. These two restrictions are removed in this study. Using some simple assumptions, methods are reported for the analysis of ideal or nonideal mixed associations by either experimental technique. The advantages and disadvantages of these two techniques for studying mixed associations are discussed. The application of these methods to various types of mixed associations is presented. 

A column experiment can also yield the value of Z>y. The radionuclide-bearing solution is added at one end of an ion-exchange medium column and is then eluted and collected in incremental volumes that are measured for radionuclide content. Ideally, the concentration of the eluted radionuclide is distributed in the incremental volumes as a Gaussian curve. For a distance of movement along the column (in this case, the length of the resin column), I, cross-sectional area a, interstitial column volume occupied by solution, i, and elutriant volume Ve measured to the peak of the radionuclide concentration curve, Eq. (3.10) applies... 

In CFAST, a set of equations that predict state variables (pressure, temperamre, etc.) are solved based on the enthalpy and mass flux over small increments of time. These equations are derived from the conservation equations for mass, momentum, energy and the ideal gas law together with plume models, vent flow equations, radiation and combustion models. Forney and Moss reviewed that there are 11 variables to be solved the mass, internal energy, density, temperature and volume for the upper and lower layers (Mu, Eu, qu, Tu, Vu and ML, EL, qL, TL, VL), and the pressure R Because there are seven constraints, any four of those variables have to be chosen as solution variables. The four variables solved are the pressure... 

The reflectivity of the solution-air interface was measured for polydimethylsiloxane solutions in toluene. In such systems, the polymer is known to be attracted at the surface because of the negative increment of the surface tension (--S mN/m). Two isotopic compositions were tested, and they are characterized respectively by ya = 4.321 and yb = -0.98 (see Eq.(H)). Ideally in the experiment, the polymer molecular weight Mu,)i and the monomer volume fraction (j>i should be independent of composition. This was however not exactly achieved ... 

---