Solvent defined

The solubility parameter 5 of a pure solvent defined initially by Hildebrand and Scott based on a thermodynamic model of regular solution theory is given by Equation 4.4 [13] ... 

At first glance the relationship between fullerene solubility and fatty acids unsaturation may appear as a surprise. However, it should be noticed that the unsaturation level of vegetable oils correlates also with their refractive index (Martinenghi, 1963). Thus, following the approach of Sivaraman et al. (1994), it is possible to show the change in solubility as function of the polarizability parameter of the solvent defined as ... 

Solvents, defined as substances able to dissolve or solvate other snbstances, are commonly used in manufacturing and laboratory processes and are often indispensable for many applications such as cleaning, fire fighting, pesticide delivery, coatings, synthetic chemistry, and separations (Grayson, 1985). Billions of ponnds of solvent waste are emitted to the environment annnaUy, either as volatile emissions or with aqneons... 

It must be emphasised that the particular region (that of the member containing four carbon atoms) of water solubility for many homologous series is determined by the arbitrary proportions of solute and solvent defined in the previous general discussion. The limit would be elsewhere for a different ratio of solute to solvent. 

Temperature and solvent define the 0 state. A polysaccharide lower Tc is in the range of refrigerated temperatures where solute-solvent interaction yields to solute-solute interaction defining the 0 temperature is thus restricted to 25-28°C. 

Donor number (or donicity), DN — is an empirical semiquantitative measure of nucleophilic properties (-> acid-base theories, subentry Lewis acid-base theory) of a solvent defined as the negative of the standard molar heat of reaction (expressed in kcalmol-1) of the solvent D with antimony pentachloride to give the 1 1 adduct, when both are in dilute solution in the inert diluent 1,2-dichloroethane, according to the reaction scheme ... 

Nitrosamlnes, ascorbic acid and, 915-916 N-1 Inked glyCOptOtKins, 59 NMDA tcceplor, 252 n minus nomenclature, fatty acids, 640 Non-lnsuiln-dependent diabetes mellitus (NIDDM), 171,173-174 obesity as risk factor, 380 weight loss and, 389-391 Nonpolar solvent, defined. 26 Nonspecific nitrogen, 460 Noiepinepbrlne, 185,623 NO synthase, 200 NPU, see Not protein utilization... 

Marenich, A.V., Cramer, C.J., Truhlar, D.G. Universal solvation model based on solute electron density and on a continuum model of the solvent defined by the bulk dielectric constant and atomic surface tensions. J. Phys. Chem. B 2009,113(18), 6378-96. 

Regular solutions are mixtures of low molar mass species with Aa = Ab= 1. Polymer solutions are mixtures of macromolecules (Aa = A 1) with the low molar mass solvent defining the lattice (Ab = 1). Polymer blends are mixtures of macromolecules of different chemical species (Aa 1 and Ab > 1). 

The formation of solvent shells around molecules is essential to prevent self-association of the solute species and to allow solution to take place. Solvents other than water which have high dielectric constants, and including some of the dipolar aprotic solvents (defined below), dissolve ionic species by separating and solvating the ions. 

For any case in which F is zero, a definite reproducible solubility equilibrium can be reached. Complete representation of the solubility relations is accomplished in the phase diagram, which gives the number, composition, and relative amounts of each phase present at any temperature in a sample containing the components in any specified proportion. Solubilities may therefore be expressed in any appropriate units of concentration, such as the quality of the solute dissolved (defined mass, number of moles) divided by the quantity either of the solvent (defined mass, volume, or number of moles) or of the solution (defined mass, volume, or number of moles). Jacques et al. (1981) have provided a compilation of the expressions for concentration and solubility. 

The terms n, a. and g are empirical solvent parameters developed by Taft and Kamlet (7). The fluoresence emission maximum of probe 1 in pure organic solvent defines the pure solvent reference line in Figure 1. When probe 1 is covalently attached to a polymer backbone which in turn is immersed in solvent, the deviation in fluorescence emission wavelength from the pure solvent correlation line reveals how the polymer perturbs the microenvironment of the probe. This microenvironment can vary from pure solvent-like to one dominated by the polymer backbone. The fluorescence emission of the probe in dry polymer is also indicated in the figure. A summary of the solvatochromatic data is discussed below. 

V2 = molar volume of the subcooled liquid solute 62 = solubility parameter of the subcooled liquid 61 = solubility parameter of the solvent = volume fraction, or the solvent defined by... 

The activity coefficient of the solvent, defined by InA = n RT at the melting temperature of the solvent is given by... 

Brief thermal treatment of coal with solvents in which the coal is insoluble (such as water or chlorobenzene) causes irreversible changes in swelling and extraction yields with good solvents (defined as those such as pyridine that swell and extract coal to the greatest extent). Physical association with strong concentration and temperature dependence is suggested as a better representation than a cross-linked network (for the insoluble portion of most coals) and provides implications for coal liquefaction. 

There is no other choice than to use the quality of solvents defined by a Pharmacopoeia. It is true that there are still discrepancies between the pharmacopoeias of different countries. It is hoped that the ICH process dealing with the harmonization of quality, safety and efficacy amongst three main zones of the world (EU, USA, Japan) will progressively reduce the remaining differences in dossiers submitted to Regulatory Authorities and the way the data are evaluated. 

Maienich, A. V. Cramer, C. J. Truhlar, D. G., Universal Solvation Model Based on Solute Electron Density and on a Continuum Model of the Solvent Defined by the Bulk Dielectric Constant and Atomic Surface Tensions. J. Phys. Chem. B 2009,113,6378-6396. 

Diffusion. The translational diffusion coefficient D is the most commonly measured transport property of polymer solutions, but as there are several distinct types of diffusion, care must be taken to interpret D properly. For c < c, Brownian motion of isolated chains in a homogeneous solvent defines the dilute solution diffusion coefficient Dq. As c increases toward c and above, chain-chain interactions modify the friction felt during chain motion. Under these conditions, the tracer- or self-diffusion coefficient Dtr is measured by tracking the path of a single chain in a macroscopically imiform mixture of chains and solvent. To distinguish the test chain from neighbors so that its path can be identified, the chain... 

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