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Events intersection

The eight tables that accompany Nagy s report reconstruct the collective experience of all 13 miners who were present during the early hours of the disaster, Tables 1-3 construct three separate chronologies of events at three temporally synchronous but geographically different locations underground and on the surface. These events intersect at three critical moments in the... [Pg.146]

The first study in which a full CASSCE treatment was used for the non-adiabatic dynamics of a polyatomic system was a study on a model of the retinal chromophore [86]. The cis-trans photoisomerization of retinal is the primary event in vision, but despite much study the mechanism for this process is still unclear. The minimal model for retinal is l-cis-CjH NHj, which had been studied in an earlier quantum chemisti7 study [230]. There, it had been established that a conical intersection exists between the Si and So states with the cis-trans defining torsion angle at approximately a = 80° (cis is at 0°). Two... [Pg.305]

To analyze this case, we employ, as before, contour algebra (see Section IX) From Figure 14, it is noticed that F23 is a contour that sunounds the (2,3) conical intersection, F34 is the contour that surrounds the two (3,4) conical intersections, and F24 is a contour that surrounds all three conical intersections. According to contour algebra the event that takes place along F24 is the sum of the events along each individual contour. Thus,... [Pg.712]

Some fraction of such events will lead to the system remaining on the Odd surface until, further along the reaction path, the Odd surface again intersects the Even surface on the product side at which time quenching to produce ground-state products can occur. [Pg.294]

Events are disjoint if the have no intersection, i.e., they are unrelated. [Pg.38]

Tlie muldplicadon dieorem provides an alternate mediod for calculating die probability of the intersection of two events. [Pg.549]

In connection witli fault trees, cut sets, and minimal cut sets are defined as follows. A cut set is a basic event or intersection of basic events that will cause the top event to occur. A minimal cut set is a cut set tliat is not a subset of any other cut set it may also be defined as the smallest combination of... [Pg.596]

Figure 8. Li + H2 Ground-state population as a function of time for a representative initial basis function (solid line) and the average over 25 (different) initial basis functions sampled (using a quasi-classical Monte Carlo procedure) from the Lit2/j) + H2(v — 0, j — 0) initial state at an impact parameter of 2 bohr. Individual nonadiabatic events for each basis function are completed in less than a femtosecond (solid line) and due to the sloped nature of the conical intersection (see Fig. 7), there is considerable up-funneling (i.e., back-transfer) of population from the ground to the excited electronic state. (Figure adapted from Ref. 140.)... Figure 8. Li + H2 Ground-state population as a function of time for a representative initial basis function (solid line) and the average over 25 (different) initial basis functions sampled (using a quasi-classical Monte Carlo procedure) from the Lit2/j) + H2(v — 0, j — 0) initial state at an impact parameter of 2 bohr. Individual nonadiabatic events for each basis function are completed in less than a femtosecond (solid line) and due to the sloped nature of the conical intersection (see Fig. 7), there is considerable up-funneling (i.e., back-transfer) of population from the ground to the excited electronic state. (Figure adapted from Ref. 140.)...
Gyr ago. There is evidence that it was reheated as a result of a shock event about 4 Gyr ago and water flowed through it, depositing carbonate globules. It was ejected form the Martian surface by another impact event and orbited the Sun on its own for about 16 million years before intersecting the Earth s orbit and landing some 13000 years ago, impacting into the ice of Antarctica where it was found. [Pg.175]

Exothermic events, such as crystallization processes (or recrystallization processes) are characterized by their enthalpies of crystallization (AHc). This is depicted as the integrated area bounded by the interpolated baseline and the intersections with the curve. The onset is calculated as the intersection between the baseline and a tangent line drawn on the front slope of the curve. Endothermic events, such as the melting transition in Fig. 4.9, are characterized by their enthalpies of fusion (AHj), and are integrated in a similar manner as an exothermic event. The result is expressed as an enthalpy value (AH) with units of J/g and is the physical expression of the crystal lattice energy needed to break down the unit cell forming the crystal. [Pg.87]

The operation A fl B denotes the intersection of two events. P[ A O It ] is thus the probability that both event A and event B occur simultaneously. [Pg.49]

Another notation fotJi iSisAnS, referred to as the intersection of the two events Ji and S. [Pg.3]

Compare this with Eq. (1.5.2). Here, we must subtract the probability of the product (or the intersection, also denoted. J n ) of the two events. [Pg.22]

Two events are said to be independent if and only if the probability of their product (or intersection) is equal to the product of their probabilities, i.e.. [Pg.23]

Although, in principle, it is possible for some fraction of the events to follow the Odd surface beyond this second intersection and to thus lead to JOdd product molecules that might fluoresce, quenching is known to be rapid in most polyatomic molecules as a result, reactions which are chemiluminescent are rare. An appropriate introduction to the use of OCD s, CCD s, and SCD s as well as the radiationless processes that can occur in thermal and photochemical reactions is given in the text Energetic Principles of Chemical Reactions, J. Simons, Jones and Bartlett, Boston (1983). [Pg.227]

The treatment of secondary-electron emission presented in this section essentially follows the ideas and organization of Sickafus which in turn was strongly influenced by Wolff . Upon entering a solid, an energetic electron is subjected to a sequence of elastic and inelastic scattering events. The collisions produce a cascade of moving electrons. The intersection of the cascade with the surface results in the emission of electrons into the gas phase. Therefore, the externally-observed, energy-... [Pg.108]

So far, the effects of the chain ends were neglected in our stochastic model for the restricted chain. Therefore, n must be much larger than the number of steps needed to form the largest excluded polygon. The partition function, which incorporates the chain-end effects and which could be also employed for exact statistical description of short non-self-intersecting chains can be obtained as follows Assume, as before, that we eliminate only lowest-order polygons of t steps. Therefore, the first t — 1 steps in the chain are described as a sequence of independent events. Eq (9), then, will be replaced by... [Pg.273]

In the electron transfer literature it has become common to describe electron transfer reactions that occur through vibrational distributions below the intersection as having occurred by nuclear tunneling and the actual electron hopping event as electron tunneling . [Pg.345]

Nonadiabatic events (transition from the excited state to the ground state at the conical intersection) pose a serious challenge because the nonadiabatic transition is rigorously quantum mechanical without a well-defined classical analog. At a simple level of theory13 (we return to a better treatment subsequently), the probability of a surface hop is given as follows ... [Pg.104]


See other pages where Events intersection is mentioned: [Pg.1043]    [Pg.266]    [Pg.592]    [Pg.547]    [Pg.619]    [Pg.35]    [Pg.35]    [Pg.234]    [Pg.479]    [Pg.156]    [Pg.157]    [Pg.158]    [Pg.135]    [Pg.21]    [Pg.357]    [Pg.357]    [Pg.86]    [Pg.466]    [Pg.107]    [Pg.126]    [Pg.209]    [Pg.936]    [Pg.263]    [Pg.535]    [Pg.34]    [Pg.116]    [Pg.34]    [Pg.343]    [Pg.154]   
See also in sourсe #XX -- [ Pg.7 ]




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