Physicochemical Mechanisms

The paragraphs below are arranged in alphabetical order and are intended only as a short reference. For readers interested in a particular topic a few references are given which serve as a link for further reading. Generally, it should be noted that the separation of the categories below is to a large extent based on historic evolution rather than physicochemical mechanisms. 

A family of 3-aminosteroids reportedly inhibit lipid peroxidation while acting as anti-inflammatories. These activities were attributed to the combination of the steroid and the amine as neither component was, by itself, efiective (Spyriounis et /., 1993). In this sense, they resemble the 21-aminosteroid lazaroids. These 3-aminosteroids most probably inhibit lipid peroxidation through a physicochemical mechanism. 

Wang, Y.C., Carrier Flotation of Anatase from Clay and its Physicochemical Mechanisms, D.E.Sc. Thesis, Columbia University, New York, 1980. 

Abstract Analysis of adequate physicochemical mechanisms of chemical contamination... 

Keywords Contamination, physicochemical mechanisms, copper smelter, Karabash ecosystem. 

Electrochemistry plays an increasingly important role in biology and medicine and the electrochemical treatment of tumors (ECT) is receiving considerable attention as a viable alternative to the more classical tumor treating approaches of surgery and chemotherapy. Dr. A. Vijh, a specialist in this area, describes both the phenomenology and the proposed physicochemical mechanisms of ECT in a comprehensive chapter. 

The effectiveness of the membrane in a certain application depends on the detailed morphology and microstructure of the membrane system, in addition to the performance of the above mentioned physicochemical mechanisms. These are critically determined by the synthesis process and this is why details of the preparation procedures are so important. The most important and well developed of these procedures are treated in Sections 13-2.9. 

The understanding of three-dimensional molecular structure and the explanation of ligand-site affinity on hand of shape and functional group complementarity ( lock and key hypothesis) naturally lead to the introduction of the pharmacophore concept in medicinal chemistry and implicitly in computational chemistry see [6] and references therein. The specific physicochemical mechanisms controlling the macromolecule-ligand interactions could be, in principle, understood on a purely... 

Isotope exchange includes processes with very different physicochemical mechanisms. Here, the term isotope exchange is used for all situations, in which there is no net reaction, but in which the isotope distribution changes between different chemical substances, between different phases, or between individual molecules. 

Likhtman, V.I., E.D. Shchukin and P.A. Rehbinder, Physicochemical Mechanism of Metals Adsorption Phenomena in the Process of Deformation and Failure of Metals, Israel Program for Scientific Translations, Jerusalem, 1964 (Translated from Russian). 

Physicochemical Mechanisms Responsible for the Beneficial Actions of Polymer Additives Tables 11.2-11.4 list examples of common polymer additives by their beneficial action(s) to the polymers during processing and products during their product life. 

Section 6 describes the use of the kinetic theory for studying physicochemical mechanics problems. An example of the theory is used to explain the observed properties for hydrogen-palladium systems. It is also used to self-consistently connect the local adsorption and diffusion characteristics of hydrogen atoms with the deformations within the metal membrane. 

It may well be that at least part of these compounds are the compositional polymorphous forms of the NiZn3-based intermetallic phase, with their structure changing from orthorhombic for Ni4Zn22 to cubic for NiZn3 of near-stoichiometric composition. This explanation is compatible with the physicochemical mechanism of layer formation. 

Ernst D. Bergmann and Bernard Pullman, Physicochemical Mechanisms of Carcinogenesis, in Quantum Chemistry and Biochemistry, No. 1, Israel Academy of Sciences and Humanities, Jerusalem, 1969. 

Note that the physicochemical mechanisms that enables us to perform the chromatographic bioseparations are not always adsorption-like but can involve ion exchange, ion exclusion, or size exclusion. Even if it is generally possible to fit experimental data with a mathematical function derived from the adsorption theory, it is strongly advisable to refer to the proper physicochemical process before modeling the separation. For instance, ion exchange can be modeled with selectivity coefficients (derived from the mass action law) that can be constant or not,18,19 ion-exclusion can be modeled thanks to theories based on the Donnan exclusion, etc. 

As shown in Equations 20 and 21, the uncoupling activity and antiinflammatory activity of fenamic acid analogs, including flufenamic and mefenamic acids, are very similar in their dependence on both hydro-phobic and electronic effects of substituents. In these equations, the subscript, i, means that the drug activities are calculated on the basis of concentration of the ionized form. It has been suggested that these two biological effects, which are also observed in many other acidic antiinflammatory drugs, have similar physicochemical mechanisms in the interaction with receptors (44). 

This somewhat critical situation may be resolved by the determination of specific and general physical and chemical regularities governing the formation and behavior of polymeric foams, which requires the use of a wide range of ideas and techniques developed in other sciences physical and colloidal chemistry, physicochemical mechanics, rheology, thermodynamics, physics of polymers, physics and mechanics of non-continuous media, physics of surface and transfer phenomena, chemical physics of oxidation and degradation processes, etc. 

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