Direct knock

Compared with the momentum of impinging atoms or ions, we may safely neglect the momentum transferred by the absorbed photons and thus we can neglect direct knock-on effects in photochemistry. The strong interaction between photons and the electronic system of the crystal leads to an excitation of the electrons by photon absorption as the primary effect. This excitation causes either the formation of a localized exciton or an (e +h ) defect pair. Non-localized electron defects can be described by planar waves which may be scattered, trapped, etc. Their behavior has been explained with the electron theory of solids [A.H. Wilson (1953)]. Electrons which are trapped by their interaction with impurities or which are self-trapped by interaction with phonons may be localized for a long time (in terms of the reciprocal Debye frequency) before they leave their potential minimum in a hopping type of process activated by thermal fluctuations. 

With carbonization, coloration of the polymers occurs [21]. Mechanisms of coloration or blackening of polymers induced by ion beams have been studied [22, 23] and two different models of blackening processes have been proposed direct knock-on of atoms from polymer chains by nuclear collision [22] and high density electronic excitation effects by an electronic excitation process [23]. 

Sputtering, unlike (thermal) evaporation, is a collision process by which an atom formerly bound to a solid becomes liberated the energy needed to hberate the atoms is provided by binary collisions either with the projectile direct knock-on) or with other target atoms that received their kinetic energy through a sequence of... 

As Exhibit 13.14 shows, yields have fluctuated on a month-on-month basis, both in Europe and in the United States, owing to the different number of days available for collection each month. For example, there was an extra bank holiday in June 2002 in the United Kingdom for the Queen s Jubilee Celebration. As more than 90% of European credit card trusts hold solely UK collateral, the reduced number of collection days in June had a significant impact on our European performance indicators. Cash collections for the master trusts fell by more than a fifth in June with a direct knock-on effect of reducing portfolio yield by almost 20%. 

H.P. Kelly at this conference. In our report we concentrate on RPAE and mainly on its generalization. In RPAE the ionization amplitude is presented as a sum of two terms, describing the direct knock-out and the induced one which is connected with a variation of the self-consistent field, caused by polarization of atomic shells under the action of the external field ... 

Knocking out genes and identification of mutations in the human genes provide information on the role of AQPs in normal physiology. The lack of some AQPs directly results in a disease phenotype, while the physiological role of many becomes clear when the putative function is challenged. 

The conventional Cl-engine operates with a relatively high compression ratio and in an unthrottled manner. Delayed direct injection of fuel in the compression process prevents knocking combustion and enables load... 

When Schildkraut introduced the monoamine theory of depression, he admitted that there was little direct evidence for it. Instead, it was based on the supposed effectiveness of antidepressant medication and the mistaken belief that reserpine makes people depressed. Schildkraut acknowledged that Most of this evidence is indirect, deriving from pharmacological studies with drugs such as reserpine, amphetamine and the monoamine oxidase inhibitor antidepressants which produce affective changes. 21 A half-century has passed since his chemical-imbalance theory of depression was introduced, and the presumed effectiveness of antidepressants remains the primary evidence in its support. But as we have seen, the therapeutic effects of antidepressants are largely due to the placebo effect, and this pretty much knocks the legs out from under the biochemical theory. 

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