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Physical chemistry origins

Annatto is a colored pigment that is extracted from the Central and South American plant Bixa orellana. The color comes from the resinous outer covering of the seeds of the plant, which is composed of the carotenoid pigments bixin and norbixin and their esters. The central portion of those molecules is the same as that of the molecule beta-carotene, and the yellow-orange color of annatto comes from the same physical chemistry origins as the orange color of beta-carotene. [Pg.106]

There are tluee very important sources of up-to-date infonnation on all aspects of Raman spectroscopy. Although papers dealing with Raman spectroscopy have appeared and will continue to appear in nearly every major chemical physics-physical chemistry based serial. The Journal of Raman Spectroscopy [35] is solely devoted to all aspects, both theoretical and experimental, of Raman spectroscopy. It originated in 1973 and continues to be a constant source of mfonuation on modem applications of Raman spectroscopy. [Pg.1196]

Based on the underlying physical chemistry of surfactants at interfaces, important features of foam stmcture, stabiHty, rheology, and their interrelationships can be considered as ultimately originating in the molecular composition of the base Hquid. [Pg.428]

In dilute solutions it is possible to relate the activity coefficients of ionic species to the composition of the solution, its dielectric properties, the temperature, and certain fundamental constants. Theoretical approaches to the development of such relations trace their origins to the classic papers by Debye and Hiickel (6-8). For detailpd treatments of this subject, refer to standard physical chemistry texts or to treatises on electrolyte solutions [e.g., that by Harned... [Pg.217]

Our mission is to explore the molecular universe with an understanding of all of the local molecular environments and constrain possible chemical reactions using the concepts of physical chemistry. With such a wide brief we need a focus and I have chosen the origins of life on Earth and on all planets - astrobiology. [Pg.1]

Chemistry deals with molecules not atoms. True thermodynamics knows no molecules with much less properties of molecules derived from chemical effects. Its origin is in such concerns as heat flow and the heat equivalent of mechanical work. Most of us have heard in physical chemistry about how it was the drilling of cannon barrels that created the connection between work and heat energy. One can take entire semester course on thermodynamics in physics and in engineering and never deal with the solution thermodynamics, which often dominates chemistry courses. To the extent that thermodynamics has been used in developing a theory for separation methods, it is almost entirely chemical thermodynamics. [Pg.405]

Among physicists, Clausius was directly influenced by Williamson s ideas about motion and equilibrium to argue that small portions of an electrolyte decompose even in the absence of an electric current and that there is a dynamic equilibrium between the decomposed and undecomposed species.47 Arrhenius took this hypothesis into an even more radical direction, stating that electrolytes exist in solution as independent ions, while van t Hoff used ideas about mobility and kinetics to develop what he called a "chemical dynamics." Just as chemical questions were influential in starting off these developments in what became the new physical chemistry, so the problem of chemical affinity was central to the origins of modem chemical thermodynamics. [Pg.134]

See Maurice Lindauer, "The Evolution of the Concept of Chemical Equilibrium from 1775 to 1923," JChem.Ed. 39 (1962) 384390 O. T. Benfey, "Concepts of Time in Chemistry," 574577 Christine King, "Experiments with Time Progress and Problems in the Development of Chemical Kinetics," Ambix 28 (1981) 7082 and Keith J. Laidler, "Chemical Kinetics and the Origins of Physical Chemistry,"... [Pg.135]

Laidler, Keith J. "Chemical Kinetics and the Origins of Physical Chemistry." Arch.Ex.Sci. 32 (1985) 4375. Langins, Janis. "The Decline of Chemistry at the Ecole Polytechnique, 17941805." Ambix 28 (1981) 119. Langmuir, Irving. "The Arrangement of Electrons in Atoms and Molecules." JACS 41 (1919) 868934. [Pg.327]

Here the USP makes a very bold statement that if the same basic chemistry is used the method should be considered equivalent in suitability. The authors interpretation is that an automated method can remain compliant. This is a somewhat drastic statement when thinking about how much a method s physical characteristics can be modified from the original method for the convenience of automation while maintaining the same physical chemistry. USP (2) goes on to state ... [Pg.378]

The word electrokinetic implies the joint effects of motion and electrical phenomena. We are interested in the electrokinetic phenomena that originate the motion of a liqnid within a capillary tube and the migration of charged species within the liquid that surrounds them. In the first case, the electrokinetic phenomenon is called electroosmosis whereas the motion of charged species within the solution where they are dissolved is called electrophoresis. This section provides a brief illns-tration of the basic principles of these electrokinetic phenomena, based on text books on physical chemistry [7-9] and specialized articles and books [10-12] to which a reader interested to stndy in deep the mentioned theoretical aspects should refer to. [Pg.157]


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