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Action volume

In a rigid system such as a glass or a polymer, the molecules M and Q are distributed at random and do not move, at least within the lifetimes of excited states. The distance distribution follows the Perrin law which is based on a very simple model. Take any excited molecule M, and ask if one quencher molecule Q happens to be within the volume of action defined by the centre-to-centre distance r. Should any molecule Q be found within this action volume, the molecule M is quenched instantaneously, but if there is no quencher Q within this space, then M emits as if no quenchers at all were present. Figure 3.39 gives a picture of the Perrin model. The mathemat-... [Pg.70]

Figure 3.39 The Perrin action volume model of static quenching. Each excited molecule is surrounded by a sphere which can contain one (or several) quenchers (a), or no quencher (b). In (a) quenching is instantaneous, in (b) there is no quenching at all... Figure 3.39 The Perrin action volume model of static quenching. Each excited molecule is surrounded by a sphere which can contain one (or several) quenchers (a), or no quencher (b). In (a) quenching is instantaneous, in (b) there is no quenching at all...
Guideline used to tax economic actors (e.g., as a function of the load of pollutants that their activity generates). Ecological monetary taxes place pressure on polluters to limit pollution provided they are sufficiently substantial to incite clean-up action. Volume 2(2). [Pg.407]

Kaufman DD. 1976. Phenols. Pp. 665-707, In Kearney PC, Kaufman DD, eds. Herbicides Chemistry, Degradation, and Mode of Action. Volume 2. 2nd edition. New York Marcel Dekker, Inc. [Pg.149]

The work process transfers energy to or from a system by an organized action. Volume work, for example, is connected with a concurrent and organized displacement of a boundary between a system and its surroundings corresponding to the movement of a piston in a cylinder. [Pg.62]

Magid Glove. Safety Matters—Fall Protection Programs Spring into Action. Volume Four, Issue One, 1998, pp. 1-2. [Pg.256]

This equation describes the additional amount of gas adsorbed into the pores due to capillary action. In this case, V is the molar volume of the gas, y its surface tension, R the gas constant, T absolute temperature and r the Kelvin radius. The distribution in the sizes of micropores may be detenninated using the Horvath-Kawazoe method [19]. If the sample has both micropores and mesopores, then the J-plot calculation may be used [20]. The J-plot is obtained by plotting the volume adsorbed against the statistical thickness of adsorbate. This thickness is derived from the surface area of a non-porous sample, and the volume of the liquified gas. [Pg.1875]

Ammonia may be estimated by dissolving the gas in a known volume of standard acid and then back-titrating the excess acid. In a method widely used for the determination of basic nitrogen in organic substances (the Kjeldahl method), the nitrogenous material is converted into ammonium sulphate by heating with concentrated sulphuric acid. The ammonia is then driven off by the action of alkali and absorbed in standard acid. [Pg.222]

However, there are other molecular properties, such as molar volume, molar refi action [3], diamagnetic susceptibility [4], and parachor [5], that can be obtained to sufficient accuracy fi om contributions, p , of its N atoms (Eq. (5)). [Pg.321]

The crude acetonitrile contains as impurity chiefly acetic acid, arising from the action of phosphoric acid on the acetamide. Therefore add to the nitrile about half its volume of water, and then add powdered dry potassium carbonate until the well-shaken mixture is saturated. The potassium carbonate neutralises any acetic acid present, and at the same time salts out the otherwise water-soluble nitrile as a separate upper layer. Allow to stand for 20 minutes with further occasional shaking. Now decant the mixed liquids into a separating-funnel, run off the lower carbonate layer as completely as possible, and then pour off the acetonitrile into a 25 ml, distilling-flask into which about 3-4 g. of phosphorus pentoxide have been placed immediately before. Fit a thermometer and water-condenser to the flask and distil the acetonitrile slowly, collecting the fraction of b.p. 79-82°. Yield 9 5 g. (12 ml.). [Pg.122]

Vertical rotary molds also employ multiple molds on a turret but rotate in a vertical plane. As each mold reaches the die exit, it grasps the parison and closes. Because of the vertical spacing between molds, intermittent extmder action is not required. Vertical wheels are used commercially for high volume apphcations. [Pg.455]

Methylene chloiide formulas are the most common organic chemical removers. The low molar volume of methylene chloride allows it to rapidly penetrate the finish by entering the microvoids of the finish. When the solvent teaches the substrate, the remover releases the adhesive bond between the finish and the substrate and causes the finish to swell. The result is a bhstering effect and an efficient rapid lifting action. Larger molecule solvents generally cannot... [Pg.550]


See other pages where Action volume is mentioned: [Pg.1654]    [Pg.1729]    [Pg.115]    [Pg.425]    [Pg.259]    [Pg.274]    [Pg.299]    [Pg.456]    [Pg.91]    [Pg.1654]    [Pg.1729]    [Pg.115]    [Pg.425]    [Pg.259]    [Pg.274]    [Pg.299]    [Pg.456]    [Pg.91]    [Pg.40]    [Pg.164]    [Pg.547]    [Pg.417]    [Pg.678]    [Pg.2062]    [Pg.2315]    [Pg.43]    [Pg.110]    [Pg.159]    [Pg.173]    [Pg.41]    [Pg.227]    [Pg.311]    [Pg.493]    [Pg.634]    [Pg.384]    [Pg.49]    [Pg.374]    [Pg.97]    [Pg.432]    [Pg.52]    [Pg.88]    [Pg.512]    [Pg.114]    [Pg.250]    [Pg.5]    [Pg.104]    [Pg.3]    [Pg.283]   
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