Hydrophilic definition

Thus, two interpretations based on two different concepts of the effect of temperature on dipole orientation have been put forward. The two views clash with each other on physical as well as chemical grounds. However, the view based on the correlation of Fig. 25 introduces chemical concepts that are absent in the other, which ignores some definite facts. For instance, although a value for dEa=0/dT is not available for Ga, the temperature coefficient of C is apparently small.905 Ga is universally recognized as a strongly hydrophilic metal. Therefore, according to the simple model of up-and-down dipoles, the effect of temperature should be major, which is in fact not the case. 

The colloidal particles can be crystalline or constitnte an amorphons agglomeration of individual molecnles. The definition also includes nonaggregated large macromolecules such as proteins. An arbitrary distinction is made between hydrophobic colloids (sols) and hydrophilic colloids (gels), which depends on the degree and type of interaction with the aqneons solvent. 

The two distinctive affinities in the surfactant molecule mentioned above serve as the basis for the commonly accepted definition of surfactant groups. According to the charge of their hydrophilic moiety, surfactants can be classified into four categories anionic, non-ionic, cationic and amphoteric. 

With 3.6 residues per turn, side chains protrude from the a-helix at about every 100° in azimuth. Since the commonest location for a helix is along the outside of the protein, there is a tendency for side chains to change from hydrophobic to hydrophilic with a periodicity of three to four residues (Schiffer and Edmundson, 1967). This trend can sometimes be seen in the sequence, but it is not strong enough for reliable prediction by itself. Different residues have weak but definite preferences either for or against being in a-helix Ala, Glu, Leu,... 

Thus, for hydrophilic molecules, there is a clear correlation between the CSF/ serum ratio and the hydrodynamic radius of the molecule. This is applicable only in the presence of a steady-state equilibrium (i.e., when the serum concentration is stable and the exchange conditions at the blood-CSF barrier are undisturbed) (Tib). The ratio for water is by definition 1.0. The concentration of the smaller chloride ion is higher in CSF than in serum therefore, in barrier dysfunction, it decreases in comparison to larger molecules. For most amino acids, active... 

Approaches to the definition of life Surfactant Ionic Amphiphilic Hydrophilic... 

To rate the wetting of powders by water i.e. their hydrophilicity. A definite value can be assigned even in cases where the contact angle is zero. ... 

O Brien. 1235 Ohmic drop, 811, 1089, 1108 Ohmic resistance, 1175 Ohm s law, 1127. 1172 Open circuit cell, 1350 Open circuit decay method, 1412 Order of electrodic reaction, definition 1187. 1188 cathodic reaction, 1188 anodic reaction, 1188 Organic adsorption. 968. 978. 1339 additives, electrodeposition, 1339 aliphatic molecules, 978, 979 and the almost-null current test. 971 aromatic compounds, 979 charge transfer reaction, 969, 970 chemical potential, 975 as corrosion inhibitors, 968, 1192 electrode properties and, 979 electrolyte properties and, 979 forces involved in, 971, 972 977, 978 free energy, 971 functional groups in, 979 heterogeneity of the electrode, 983, 1195 hydrocarbon chains, 978, 979 hydrogen coadsorption and, 1340 hydrophilicity and, 982 importance, 968 and industrial processes, 968 irreversible. 969. 970 isotherms and, 982, 983... 

Lactic acid is an example. It is conveniently added to the polyol and upon reaction with the isocyanate, it is inserted into the backbone. Upon exposure to fluids in the body, the polymer is cut at the insertion site. The reduction in tensile properties is dramatic. Although the fragments are suspect, the result is by definition degradable. A number of researchers at W.R. Grace prepared biodegradable hydrophilic polyurethanes by a similar technique but the product was never available commercially. 

We have defined the properties faced by developers of new growing media. Based on these definitions, it is clear that reticulated foam would not be useful for such applications. Even at the finest pore size, virtually no water is retained during this test. If, however, we were to graft hydrophilic polyurethane onto a reticulated foam, the grafted polyurethane increases the amount of water retained in the moisture tension test. If an organic fiber such as peat moss is included in the hydrophilic polyurethane, the effect is even more pronounced. Applications in both hydroponic and soil planting are anticipated from this technology. 

Surfactants. By definition every detergent product contains one or more types of surfactants. Basically, every surfactant is an organic compound consisting of two parts (I) a hydrophobic portion, normally including a long hydrocarbon chain, and (2) a hydrophilic portion, which renders the entire compound sufficiently soluble or dispersible in water or other polar solvent to serve its intended use. Together, these combined hydrophobic and hydrophilic moieties render the compound surface-active—able to concentrate at the interface between a surfactant solution and another phase, such as air. soil, and textile substrate to be cleaned. 

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