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Fraction solute separation, definition

Water soluble protein with a relative molecular mass of ca. 32600, which particularly contains copper and zinc bound like chelate (ca. 4 gram atoms) and has superoxide-dismutase-activity. It is isolated from bovine liver or from hemolyzed, plasma free erythrocytes obtained from bovine blood. Purification by manyfold fractionated precipitation and solvolyse methods and definitive separation of the residual foreign proteins by denaturizing heating of the orgotein concentrate in buffer solution to ca. 65-70 C and gel filtration and/or dialysis. [Pg.1493]

It has been proposed to define a reduced temperature Tr for a solution of a single electrolyte as the ratio of kgT to the work required to separate a contact +- ion pair, and the reduced density pr as the fraction of the space occupied by the ions. (M+ ) The principal feature on the Tr,pr corresponding states diagram is a coexistence curve for two phases, with an upper critical point as for the liquid-vapor equilibrium of a simple fluid, but with a markedly lower reduced temperature at the critical point than for a simple fluid (with the corresponding definition of the reduced temperature, i.e. the ratio of kjjT to the work required to separate a van der Waals pair.) In the case of a plasma, an ionic fluid without a solvent, the coexistence curve is for the liquid-vapor equilibrium, while for solutions it corresponds to two solution phases of different concentrations in equilibrium. Some non-aqueous solutions are known which do unmix to form two liquid phases of slightly different concentrations. While no examples in aqueous solution are known, the corresponding... [Pg.557]

Navard and Haudin studied the thermal behavior of HPC mesophases (87.88) as did Werbowyj and Gray (2), Seurin et al. (Sp and, as noted above, Conio et al. (43). In summary, HjPC in H2O exhibits a unique phase behavior characterized by reversible transitions at constant temperatures above 40 C and at constant compositions when the HPC concentration is above ca. 40%. A definitive paper has been recently published by Fortin and Charlet ( who studied the phase-separation temperatures for aqueous solutions of HPC using carefully fractionated HPC samples. They showed the polymer-solvent interaction differs in tiie cholesteric phase (ordered molecular arrangement) from that in the isotropic phase (random molecular arrangement). [Pg.265]

The thermodynamic dead volume includes those static fractions of the mobile phase that have the same composition as the moving phase, and thus do not contribute to solute retention by differential interaction in a similar manner to those with the stationary phase. It is seen that, in contrast to the kinetic dead volume, which by definition can contain no static mobile phase, and as a consequence is independent of the solute chromatographed, the thermodynamic dead volume will vary from solute to solute depending on the size of the solute molecule (i.e. is dependent on both ( i )and (n). Moreover, the amount of the stationary phase accessible to the solute will also vary with the size of the molecule (i.e. is dependent on (%)). It follows, that for a given stationary phase, it is not possible to compare the retentive properties of one solute with those of another in thermodynamic terms, unless ( ), (n) and (fc) are known accurately for each solute. This is particularly important if the two solutes differ significantly in molecular volume. The experimental determination of ( ), (n) and( ) would be extremely difficult, if not impossible In practice, as it would be necessary to carry out a separate series of exclusion measurements for each solute which, at best, would be lengthy and tedious. [Pg.32]

The definitions based on molarities, c, are very similar to those based on molalities, and again the solvent must be considered separately from the solutes. (The molarity is defined as the number of moles per liter of solution, and is dependent on the pressure and temperature.) Molarities, like the molalities, are used primarily for solutions for which the concentration ranges are limited. For dilute solutions the molarities of the solutes are approximately proportional to their mole fractions. We thus express the chemical potential of the fcth solute in solution at a given temperature and pressure as... [Pg.188]

Dissolved amino acids are commonly divided into two pools that must be analyzed separately DFAA exist as individual monomers in solution, while DCAA are defined operationally as additional amino acids liberated by acid hydrolysis. DCAA are thus presumably present mostly as polypeptides, a supposition supported in at least the high molecular weight (HMW) fraction by N-nuclear magnetic resonance (NMR) spectroscopy data (discussed below). The operational nature of the DFAA versus DCAA definitions means that amino acids liberated from difficult matrixes (e.g., humic substances) also could make up a part of DCAA. Total hydrolysable amino acid (THAA) is another term commonly used to denote both pools together, when the sample is hydrolyzed but DFAA are not independently determined. Because the DFAA pool is typically much smaller than DCAA, THAA values are often assumed to be similar to DCAA. [Pg.1230]

After having been deprived of these three fractions, the liquid still contains albuminoid substances in solution, which can be diAdded into two new fractions. The first is precipitated when the liquid, previously saturated with anunonium sulphate, is addified the second remains in solution. We have, thus, definitely separated all the products of peptic hydrolysis into five portions. [Pg.218]

But even if we leave the enigmatical radon family alone the situation still remains unclear. In 1900 W. Crookes observed a strange phenomenon. After fractional crystallization of a uranium compound he obtained a filtrate and a precipitate. Uranium remained in the solution but it exhibited no activity. On the contrary, the precipitate did not contain uranium but exhibited a high-intensity radioactivity. On the strength of his observations Crookes made a paradoxical conclusion that uranium was not radioactive by itself, and its radioactivity was due to some admixture which he managed to separate from uranium. As if he had ill premonitions, Crookes refrained from giving the admixture any definite name and referred to it as uranium-x (UX). Later it was found that uranium restores its activity after... [Pg.184]

Definition of terms relating to individual macromolecules, their assemblies, and dilute solution.This document includes the recommended definitions for molecular weight, molecular weight averages, distribution functions, radius of gyration, end-to-end-distance vector, the Flory-Huggins-Staverman theory, solution viscosity, scattering of radiation by polymers and polymer solutions, fractionation, separation techniques, and so on. The document on dispersity is an important extension of this recommendation. [Pg.479]

Fractionation of proteins is too large a field to be completely reinewed here, but certain facts stand out clearly. The distinction between different classes of proteins, e.g., albumins and globulins, was for a long time made completely on the basis of solubility in water, salt solutions and other solvents. The inadequacy of such a method of classification was pointed out by Block, who attempted to introduce chemical factors into it as well. Butler and coworkers (204) had previously shown that albumin and globulin separation by neutral salts was not sharp, and that there was much overlapping of the fractions. Duli e (205) found i>oor agreement between the sodium sulfate method of Howe (206) and the ammonium sulfate method, while Macheboeuf (207) concluded from a comparative study of several fractionation methods, that the definitions of the protein fractions were indefinite unless the method of separation was specified. [Pg.160]

With this definition of M, equation 13 can be empirically fit to experimental sorption data an effective diffusion coefficient is obtained from this parametric fit. The fraction of accessible pores has often been neglected in applying modifications of continuum formulations to real porous media. In cases where is less than unity, this leads to erroneously high predictions for the effective diffusion coefficient. In searching for the physical determinants of effective diffusivity in porous materials, it is important to separate the confounding effect of inaccessible porosity from real reductions in the diffusivity of solute. [Pg.179]


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See also in sourсe #XX -- [ Pg.141 ]




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Fraction solute separation

Fractional definition

Fractionation separation

Separation definition

Separation fractions

Separators solutions

Solute definition

Solute separation

Solution separations

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