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Energy Virtual Substance

Chemicals are ubiquitous as air, carbohydrates, enzymes, lipids, minerals, proteins, vitamins, water, and wood. Naturally occurring chemicals are supplemented by man-made substances. There are about 70000 chemicals in use with another 500-1000 added each year. Their properties have been harnessed to enhance the quality of life, e.g. cosmetics, detergents, energy fuels, explosives, fertilizers, foods and drinks, glass, metals, paints, paper, pesticides, pharmaceuticals, plastics, rubber, solvents, textiles thus chemicals are found in virtually all workplaces. Besides the benefits, chemicals also pose dangers to man and the environment. For example ... [Pg.1]

Until about 40 years ago, these elements were referred to as "inert gases" they were believed to be entirely unreactive toward other substances. In 1962 Neil Bartlett, a 29-year-old chemist at the University of British Columbia, shook up the world of chemistry by preparing the first noble-gas compound. In the course of his research on platinum-fluorine compounds, he isolated a reddish solid that he showed to be 02+(PtFB-). Bartlett realized that the ionization energy of Xe (1170 kJ/mol) is virtually identical to that of the 02 molecule (1165 kJ/mol). This encouraged him to attempt to make the analogous compound XePtF6. His success opened up a new era in noble-gas chemistry. [Pg.190]

Instruments are calibrated with substances of known relative molecular mass and very accurate mass measurements can be made with this type of analyser. Sensitivity is very high and there is virtually no upper limit to the working mass range. The performance of TOF instruments can be improved further by the incorporation of an electrostatic reflector (reflectron) which ensures that all ions of identical mass reach the detector simultaneously by correcting for any differences in their kinetic energies. [Pg.430]

There is not only a controversy over nomenclature but there is also a comparable discussion over the number of metabolites in the metabolome. Almost by definition, any substance involved in metabolism either as a product of metabolism or necessary for metabolism should be considered, and estimates of 3000 major metabolites have been reported.9 Others have indicated that any metabolite smaller than 1000 Da, which would incorporate virtually all energy pathways, all catabolic pathways, and many biosynthetic pathways, might be reasonable.5... [Pg.189]

Coenzyme QIO, or CoQlO, is a substance that occurs naturally in virtually all of our bodies tissues, especially in muscle tissue. It s so widespread throughout the body that another name for it is ubiquinone, referring to its ubiquitous nature. CoQlO regulates energy in muscle cells. As we age, the amount in our bodies declines. For that reason, it has been speculated that supplementation would improve energy levels. That claim hasn t been well substantiated, but there are other and better reasons to consider supplementation. [Pg.188]

The mechanism by which the endocrine and metabolic response is activated has not been defined clearly. There is evidence that both neural impulses and tissue substances play a part in stimulating what is virtually a total increase in endocrine activity. Many of the hormones which are increased have metabolic functions which include the maintenance of blood glucose levels. This appears to be a fundamental biological defense mechanism whereby an essential energy source is preserved for the central nervous system. [Pg.256]

The electron in the electron transport chain is not free like in a metal wire. Therefore the electron motion in each act involves surmounting an energy barrier. As was shown in Refs. 16 and 108-110, a substantial role in this process is played by the conformations of the macromolecular components of the electron transport chain. Nevertheless, the simplest model systems of electron transport realized on bilayer lipid membranes were virtually based on the concept of a membrane as a thin liquid hydrocarbon in which a substance capable of redox transformations is dissolved, the products of this reaction being able to diffuse inside the bilayer. The electron transport from the aqueous phase containing a reducer amounts to injection of charges into the nonaqueous phase if it contains an electron acceptor ... [Pg.145]


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See also in sourсe #XX -- [ Pg.202 ]




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