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Probability scheme

This hypothesis is based on the fact that Arapides (9) was able to demonstrate the formation of the acyclic compound (185), which is an intermediate in the conversion of a-thiocyanatoketone to 2-hydroxythia-zole, but an intermediate such as 186 seems to be more probable (Scheme 95). [Pg.273]

FIGURE 21.8 A probable scheme for electron flow in Complex II. Oxidation of succinate occurs with rednction of [FAD]. Electrons are then passed to Fe-S centers and then to coenzyme Q (UQ). Proton transport does not occur in this complex. [Pg.684]

The same approach applies to alternate partition functions the WL output is used directly in the macroscopic probability scheme. For example, in the previous grand canonical scenario, the WL simulation would yield which would be substituted directly into the macrostate probabilities as Q exp(J ) for subsequent results generation. [Pg.103]

A more detailed discussion of the subtleties in formulating correct acceptance criteria can be found in [1], For the purpose of this chapter, we will focus on ensembles in general rather than acceptance criteria specifically, with the understanding that once the configurational probabilities are fixed the criteria follow directly. With this in mind, we will sometimes present the microstate probability scheme without discussing the associated acceptance criteria. [Pg.354]

Obviously, once the hexatriene stage is reached, its cis isomer very rapidly gives 1,3-cyclohexadiene (59). Radiotracer studies have confirmed this cyclization step 20). However, tra 5-l,3,5-hexatriene may also be produced with almost the same probability (Scheme I). We do not agree with Rozen-... [Pg.283]

The probable scheme of decomposition of nitrosourea in the body into active components is shown below. [Pg.399]

This scheme, however, has the disadvantage of ignoring the influence of the nitronium ion (NO ) on the reaction, whereas, as expounded in the chapter on nitration theories (Vol. I), the nitronium ion is of enormous importance for such a reaction. In this connection Lamberton [43] suggests alternative schemes which appear more probable. Scheme (8) leads to the formation of a nitramine and scheme (9) to a salt of nitric acid ... [Pg.12]

A decomposition Nof a system containing N elements is any partition of these elements into disjoint subsets of equivalent elements by a selected equivalence relation. A finite probability scheme can be associated to this decomposition as follows ... [Pg.164]

A finite probability scheme can be associated with this decomposition as the following ... [Pg.293]

A further use of linear extension is the probability scheme (ranking probabilities) that they provide. Probability plots are depicted for the three sites 1, 17 and 91 (Fig. 21a) and for site 5 (Fig. 21b), respectively. (See also the contributions, chapters by Voigt and Bruggemann, p. 327 Bruggemann et al., p. 237 Carlsen, p. 163. [Pg.99]

This entropic approach to bonded fragments in a molecule has created a new impetus to a search for novel, information-distance measures of the chemical bond multiplicities [27,28]. The resulting entropic bond-orders reflect upon the molecular communication system involving the promolecular input probability scheme and the molecular output probability scheme, of finding electrons on specified AIM. Clearly, the promolecule probabilities of atomic assignments are modified in a molecule as a result of the communication noise created by the electron delocalization throughout the molecular system, via a network of the chemical bonds. Specific entropy differences have been found to reflect both the global and... [Pg.151]

Rate constants, based on potential profiles such as those displayed in Figure 7, were evaluated with use of the WKB expression. The ingredients for the evaluation of k(R), the barrier height above the reactant well eigenvalue and the well frequency, were obtained by solution of the Schrodinger equation for these potential surfaces. We also developed a survival probability MD scheme to account for the interference between solvation dynamics and proton transfer, and then compared the two predictions. The survival probability decays reasonably exponentially. The rate constant obtained from the survival probability scheme is about 50% smaller than the rate constant obtained by direct configuration averaging. The value of 0.25 ps and shows that this... [Pg.157]

The scheme of dehydration of alcohol and ether on silica-alumina catalyst proposed by us appears to us to explain rather well the experimental facts and to be one of the most probable schemes to reflect the actual mechanism of this catalytic reaction. [Pg.806]

A more probable scheme for the el troch ieal substitution implies an intermediate radical cation losing a proton with conversion into a benzyl radical oxidized on the anode to a benzyl cation (cf. [Pg.190]

In oxidative epoxidation reactions besides of oxidizing agent often various catalysts systems are used [14]. It was established that the rate of heterolytic decomposition of 0-0 bonds in tertiary-butyl peroxide in the presence of catalysts such as Mo(CO)g proceeds in result of complexation between metal and hydroperoxide. By the authors suggested the probable schemes transition condition, without discussion of valent state of metal (Scheme 2). [Pg.283]

Conversion of a Racemic Substrate via a meso-it-Allylpallaclium Intermediate Although the chirality transfer works very well in the case of unsymmetrically 1,3-disubstituted allylic substrates, problems arise when the substrates have two identical substituents on both sides of the allyl fragment [44]. If 1,3-disubstituted substrates are used, symmetrical JT-allylpalladium complexes (meso-complexes) are formed, which can react with nucleophiles at both allylic positions with the same probability (Scheme 12.26). Therefore, the chiral information of the substrates... [Pg.938]

The authors suggest that the most probable scheme is an initial intramolecular cyclisation of the ortho-acid ester centres generating the corresponding anhydrides which then react as usual to produce polyamic acids, finally subjected to thermal imidization. The intermediate compound 35 in Fig. 16 would be the first step of polyamic acid formation when one anhydride group has been produced and immediately opened by one amine function. The reaction is thermally controlled to produce oligomers which are marketed in the form of either adhesive films, pastes, or solid powders. Polycondensation and imidization are completed on processing at high temperature, followed by a postcure at 316°C. [Pg.253]

Figure 5. (a) Probable scheme of the catalytic hydrogen evolution in the Brdicka reaction, (b) Real voltammograms of 20 fmol metallothionein (red line) and the Brdicka s solution as a supporting electrolyte containing 1 mM Co(NH3)5Cl3 and 1 M NH3(aq ) + NH4CI, pH 9.6 (black line). Parameters of DPV method were as follows initial potential -0.35 V, end potential -1.8 V, modulation time 0.057 s, time interval 0.2 s, step potential 1.05 mV/s, modulation amplitude 250 mV, time of accumulation of MT 120 s, Eads = 0 V. All measurements were carried at temperature of 5 °C. [Pg.155]

An important generalization of Shannon s entropy, called the relative (cross) entropy, also known as the entropy deficiency, missing information or the directed divergence, has been proposed by KuUback and Leibler [5, 6]. It measures the information distance between the two (normalized) probability distributions for the same set of events. For example, in the discrete probability scheme identified by events a = (a,) and their probabilities P(a) = P(a = Pi) = this discrimination information in p with respect to the reference distribution... [Pg.55]

The entropy deficiency provides a measure of the information resemblance between the two compared probability schemes. The more the two distributions differ from one another, the larger the information distance. For individual events the logarithm of the probability ratio 7, = log(p,/p °), called the surprisal, provides a measure of the event information in the current distribution relative to that in the reference distribution. The equality in the preceding equation takes place only for the vanishing surprisal for all events, i.e., when the two probability distributions are identical. [Pg.55]


See other pages where Probability scheme is mentioned: [Pg.97]    [Pg.99]    [Pg.354]    [Pg.21]    [Pg.313]    [Pg.939]    [Pg.311]    [Pg.152]    [Pg.157]    [Pg.111]    [Pg.252]    [Pg.145]    [Pg.163]    [Pg.283]    [Pg.26]    [Pg.186]    [Pg.110]    [Pg.314]    [Pg.60]    [Pg.54]    [Pg.57]   
See also in sourсe #XX -- [ Pg.99 ]




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