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Energy transfer impact

The product of the collision energy E(L) and collision frequency f L) is integrated over all crystals in the distribution to obtain the total rate of energy transfer. Different approaches have been used to estimate E(L) and f L), both for particle impacts and turbulent fluid induced attrition. [Pg.149]

Ne is metastable neon produced by electron impact. Ne transfers its excitation to hydrogen molecules. The hydrogen molecules participating in these energy transfer collisions are produced in highly excited preionized states which ionize after a time lag sufficient to permit the initial neon and hydrogen collision partners to separate. The hydrogen ion is formed in the v = 5 or 6 quantum states and reacts with a second neon... [Pg.98]

Reactions of Complex Ions. For reactions of systems containing H2 or HD the failure to observe an E 1/2 dependence of reaction cross-section was probably the result of the failure to include all products of ion-molecule reaction in the calculation of the experimental cross-sections. For reactions of complex molecule ions where electron impact ionization probably produces a distribution of vibrationally excited states, kinetic energy transfer can readily open channels which yield products obscured by primary ionization processes. In such cases an E n dependence of cross-section may be determined frequently n = 1 has been found. [Pg.105]

The unique power of synthesis is the ability to create new molecules and materials with valuable properties. This capacity can be used to interact with the natural world, as in the treatment of disease or the production of food, but it can also produce compounds and materials beyond the capacity of living systems. Our present world uses vast amounts of synthetic polymers, mainly derived from petroleum by synthesis. The development of nanotechnology, which envisions the application of properties at the molecular level to catalysis, energy transfer, and information management has focused attention on multimolecular arrays and systems capable of self-assembly. We can expect that in the future synthesis will bring into existence new substances with unique properties that will have impacts as profound as those resulting from syntheses of therapeutics and polymeric materials. [Pg.1343]

Eastman, R. H., 158, 166 Eaton, P. F., 460 Eigen, M., 80 Eisenberg, W., 125 Electrocyclic addition, 46 Electrocyclic reaction rules, 339 Electrocyclic reactions, 402,408 4n-examples, 408 (4n + 2)-examples, 410 Electron impact spectroscopy, triplet energy, 220-223 Electronic energy transfer, 267 Electronic integral, 21 Electronic transitions /-a ,16 n -Mr, 16... [Pg.297]

In Bohr s theory, only estimates of maximum and minimum impact parameters are necessary. Better computations are required for determining the transverse distribution of lost energy or the effect of secondary electrons. The minimum impact parameter according to classical mechanics is ze2/mv2 from angular momentum consideration in quantum mechanics, it is h /mv. In practice, the larger of these two is taken. Also, the impulse approximation used by Bohr for the maximum impact parameter is not an absolute rule energy transfer beyond bmax falls off exponentially (Orear et al., 1956 Mozumder, 1974). [Pg.17]

Excited states may be formed by (1) light absorption (photolysis) (2) direct excitation by the impact of charged particles (3) ion neutralization (4) dissociation from ionized or superexcited states and (5) energy transfer. Some of these have been alluded to in Sect. 3.2. Other mechanisms include thermal processes (flames) and chemical reaction (chemiluminescence). It is instructive to consider some of the processes generating excited states and their inverses. Figure 4.3 illustrates this following Brocklehurst (1970) luminescence (l— 2)... [Pg.78]

Impact Number j qU0 2Ach TL-T ) Compare kinetic energy transfer rate to heat extraction rate Matson et al. [409]... [Pg.306]

The secret to stopping a bullet with a fairly soft fabric is that it behaves in much the same way as the netting on the goal frame used in hockey. When a hockey puck strikes a net at 100 km/h, its kinetic energy is transferred to the lengths of twine of the goal net. This twine is an interlaced mesh that has strands which stretch horizontally and vertically to disperse the energy of impact over a wide area. [Pg.205]

At this frequency of impacts the energy transferred to the powder would be comparable with that achieved in a planetary ball mill. The milling cylinder suitable for reactive milling is shown in Fig. 1.8. [Pg.36]

The above nonstatistical view of reaction (2) has been reinforced by recent experiments made under LP conditions and presents a great challenge to the GPIC community. It now appears that the LP rate constants obtained for any nonstatistical reaction of this type will be extremely difficult to interpret in terms of candidate mechanisms and potential energy surfaces envisioned for that reaction. An accurate prediction of for such reactions would have to include a set of very complex factors, some of which are not presently well understood. These factors would include the initial distributions of energy within the set of collision complexes, X, formed under all possible collision impact conditions the rates of energy transfer between all vibrational modes within the species, X and Y and the mode-dependent rate constants for the motion of individual species within the sets of ion complexes, X and Y, in both directions on the reaction coordinate. [Pg.225]


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See also in sourсe #XX -- [ Pg.5 , Pg.18 , Pg.19 , Pg.20 , Pg.21 ]




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