Molecular properties homogeneity

Application of new analytical methods, in particular of different types of electrophoresis, has also provided new data on the molecular properties of these enzymes and has set more rigorous criteria of their purity and homogeneity. 

The development of the method started in the mid 1920 s with the work of Thomas and Fermi [8, 9]. The aim was to formulate an electronic structure theory for the solid state, based on the properties of a homogeneous electron gas, to which we introduce a set of external potentials (i.e. the atomic nuclei). The original formulation, with later additions by Dirac [10] and Slater [11], was, however, inadequate for accurate description of atomic and molecular properties, and it was not until the ground-breaking work of Kohn and coworkers in the mid 1960 s that the theory was put in a form more suited to computational chemistry [12,... 

Five organic solvents [acetonitrile, methanol, tetrahydrofuran (THF), acetone, and dimethylformamide], which are homogeneously miscible with water, have been used as modifiers to study the relationship of the selectivity of the solvent to the molecular properties of analytes. The polar interaction... 

These conclusions can be obtained on the nonrelativistic level, and it is possible in theory to practice proton and electron spin resonance without permanent magnets, at much higher resolution, without the need for very high homogeneity, and with a novel chemical shift pattern, or spectral fingerprint, determined by a site-specific molecular property tensor, to be described later in this section. 

The idea of calculating atomic and molecular properties from electron density appears to have arisen from calculations made independently by Enrico Fermi and P.A.M. Dirac in the 1920s on an ideal electron gas, work now well-known as the Fermi-Dirac statistics [19]. In independent work by Fermi [20] and Thomas [21], atoms were modelled as systems with a positive potential (the nucleus) located in a uniform (homogeneous) electron gas. This obviously unrealistic idealization, the Thomas-Fermi model [22], or with embellishments by Dirac the Thomas-Fermi-Dirac model [22], gave surprisingly good results for atoms, but failed completely for molecules it predicted all molecules to be unstable toward dissociation into their atoms (indeed, this is a theorem in Thomas-Fermi theory). 

In the relations between the macroscopic susceptibilities y , y and the microscopic or molecular properties a, ft, y, local field corrections have to be considered as explained above. The molecule experiences the external electric field E altered by the polarization of the surrounding material leading to a local electric field E[oc. In the most widely used approach to approximate the local electric field the molecule sits in a spherical cavity of a homogenous media. According to Lorentz the local electric field [9] is... 

Antibodies are very diverse in molecular properties, chemical characteristics, and biological activity. Purification strategies are therefore very diverse, since they are based on a large variety of molecular interactions. Antibodies have, however, several common properties that are frequently exploited for their capture from the initial feedstock. It is known in fact that several physicochemical and structural similarities are shared between antibody molecules, and that is why they are considered as an homogeneous group of proteins. 

When chirality is involved, information on solid-state structures and supra-molecular properties must be obtained by solid-state circular dichroism (CDf spectroscopy, as certain characteristics may be lost upon dissolution. However extreme care is required to obtain artifact-free solid-state CD spectra. This is because CD spectra in the solid state (except for special homogeneous cases [9,10]) are inevitably accompanied by parasitic signals that originate from thd macroscopic anisotropies of a sample such as LD (linear dichroism) and LB (linear birefringence) [11-16]. We have been working in the field of solid-state chirality for the last 30 years and recently developed a novel universal chiroptical spectrophotometer, UCS J-800KCM, for the measurement of true CD and circular birefringence (CB) spectra in the solid state [17]. 

These materials mainly include graphites, carbon blacks and graphitized carbon blacks, and are frequently used as standards in adsorption at high and low surface coverage due to the lack of porosity and their homogeneous surfaces [61-64]. For these reasons it is easy to find a relationship, for the adsorption of non-polar molecules (n-alkanes), between the specific retention volumes and a molecular property of the adsorbate such as the polarizability or the molecular volume, and the amount adsorbed, V, which is nor-... 

Here, (4.) gives the diffusivity in terms of molecular properties. In this case, k is the Absolute Reaction Rate constant given for a solution which is homogeneous, in which conducting holes are distributed at random along with the solute molecules across the thin film quasi-lattice. The specific rate... 

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