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N-realizer

This example aside, the utility of the electrohydrocyclization reaction in the assembly of natural products remains essentially untapped. The reason for this observation is not entirely clear. Consider, for example, the rapid and efficient construction of the perhydrophenanthrene skeleton as exemplified by the conversion illustrated below [18]. The reaction is stereospecific, leading to the trans-anti-trans ring fused adduct 13 in a 65 to 72% yield. It takes little thought to imagine the application of this powerful transformation to the synthesis of steroids. Yet, this opportunity has not b n realized. [Pg.6]

By Bayes s rule, the posterior probability on a Monte Carlo realization of a model equals the probability of observing the site-specific output data if the realization is correct, times the prior probability that the realization is correct, normalized such that the sum of the posterior probabilities of the Monte Carlo realizations equals 1. In Monte Carlo analysis, all realizations are equally likely (i.e., the pritM probability on each realization of an n-realization Monte Carlo simulation is 1/n). Therefore, the BMC acceptance-rejection procedure boils down to the following The probability that a model realization is correct, given new data, equals the relative likelihood of the having observed the new data if the realization is correct. [Pg.60]

Although I have spoken of the core as concrete, it probably has to include (as the N-realizer does) negative existential states of affairs. For example, the states of affairs contributing to the instantiation of my height has to include its not being the case that below my feet and above my head there are microentities of certain sorts related to those inside my body in the ways the latter are related to one another. [Pg.143]

Suppose that in a particular case the N-realizer of an instance of P includes a microphysical state of affairs Cp that qualifies as a / -core. We can suppose that the possessor of P also has property Q, where Q is of a kind such that any possessor of P must have some property of that kind (as, for example, any possessor of a particular shape must have some mass or other). Let Cq be the Q-core that is also a part of the N-realizer of the / -instance and Q-instance. Now it seems that the P instance could have occurred without the instance of Q occurring, and so without Cq occurring. For example, if P is the property of having a certain shape and Q is the property of having a certain mass, then although the instance of P must be accompanied by an instance of some mass property, it does not seem necessary that it should have been accompanied by an instance of the particular mass property Q. (For example, if some of the matter inside a thing had leaked out, it might have had the same shape but a lesser mass.) And if the instances have different modal properties, so should their total (specific) realizers. We can achieve this as follows. [Pg.144]

Consider the set of possible N-realizers that have Cp as a. part. This includes the actual N-realizer that also has Cq as a part, but it includes possible N-realizers that do not have Cq as a part (in our example, these are N-realizers that realize the instance of P but that realize instances of slightly different mass properties). The members of this set represent the different ways in which the particular instance of P could be, or could have been, realized. We can think of the disjunctive state of affairs whose disjuncts are members of that set as the realizer of that instance of P. Call this the S-realizer (5 for specific) of the instance of P. [Pg.144]

Generation of N realizations of the n-dimensional random parameter vector 0 according to a given n-dimensional joint probability density function (PDF). [Pg.31]

Computation by FE analysis of N response curves for each component of the response vector r, corresponding to the N realizations of the random parameter vector 0. [Pg.31]

One approach to a mathematically well defined performance measure is to interpret the amplitude values of a processed signal as realizations of a stochastic variable x which can take a discrete number of values with probabilities P , n = 1,2,..., N. Briefly motivated in the introduction, then an interesting quality measure is the entropy H x) of the amplitude distribu-... [Pg.90]

As is evident firom the theory of the method, h must be the height of rise above a surface for which AP is zero, that is, a flat liquid surface. In practice, then, h is measured relative to the surface of the liquid in a wide outer tube or dish, as illustrated in Fig. n-6, and it is important to realize that there may not be an appreciable capillary rise in relatively wide tubes. Thus, for water, the rise is 0.04 mm in a tube 1.6 cm in radius, although it is only 0.0009 mm in one of 2.7-cm radius. [Pg.16]

Results can sometimes be unexpected. The first study of this type made use of labeled Aerosol OTN [111], an anionic surfactant, also known as di-n-octylsodium sulfosuccinate. The measured F was twice that in Eq. III-93 and it was realized that hydrolysis had occurred, that is, X + H2O = HX + OH , and that it was the undissociated acid HX that was surface-active. Since pH was essentially constant, the activity of HX was just proportional to C. A similar behavior was found for aqueous sodium stearate [112]. [Pg.78]

It is important to realize that while the uppennost diagonal elements of these matrices are numbers, the other diagonal element is a matrix of dimension N. Specifically, these are the matrix representations of Hq and Fin the basis q which consists of all the original set, apart from i.e. [Pg.47]

Head A J and Sabbah R 1987 Enthalpy Recommended Reference Materials for the Realization of Physicochemical Properties ed K N Marsh (Oxford Blackwell)... [Pg.1919]

Peek K, Stryer L, Glazer A N and Mathies R A 1989 Single-moleeule fluoresoenoe deteotion autoeorrelation eriterion and experimental realization with phyooerythrin Proc. Natl Acad. Sc/. USA 86 4087-91... [Pg.2504]

It is essential to realize that the energies (i H Oi> of the CSFs do n represent the energies of the true electronic states Ek the CSFs are simply spin- and spatial-symmetry adapted antisymmetric functions that form a basis in terms of which to expand the true electronic states. For R-values at which the CSF energies are separated widely, the true Ek are rather well approximated by individual (i H Oi> values such is the case near Rg. [Pg.304]

Ei=i N F(i), perturbation theory (see Appendix D for an introduetion to time-independent perturbation theory) is used to determine the Ci amplitudes for the CSFs. The MPPT proeedure is also referred to as the many-body perturbation theory (MBPT) method. The two names arose beeause two different sehools of physies and ehemistry developed them for somewhat different applieations. Later, workers realized that they were identieal in their working equations when the UHF H is employed as the unperturbed Hamiltonian. In this text, we will therefore refer to this approaeh as MPPT/MBPT. [Pg.483]

The first-order MPPT wavefunction can be evaluated in terms of Slater determinants that are excited relative to the SCF reference function k. Realizing again that the perturbation coupling matrix elements I>k H i> are non-zero only for doubly excited CSF s, and denoting such doubly excited i by a,b m,n the first-order... [Pg.580]

Comparison with the empirical Equation (1.4) shows that = /re /S/z eg and that n" = 2 for the Balmer series. Similarly n" = 1, 3, 4, and 5 for the Lyman, Paschen, Brackett and Pfimd series, although it is important to realize that there is an infinite number of series. Many series with high n" have been observed, by techniques of radioastronomy, in the interstellar medium, where there is a large amount of atomic hydrogen. For example, the (n = 167) — ( " = 166) transition has been observed with V = 1.425 GFIz (1 = 21.04 cm). [Pg.5]

Acrylonitrile (AN), C H N, first became an important polymeric building block in the 1940s. Although it had been discovered in 1893 (1), its unique properties were not realized until the development of nitrile mbbers during World War II (see Elastomers, synthetic, nitrile rubber) and the discovery of solvents for the homopolymer with resultant fiber appHcations (see Fibers, acrylic) for textiles and carbon fibers. As a comonomer, acrylonitrile (qv) contributes hardness, rigidity, solvent and light resistance, gas impermeabiUty, and the abiUty to orient. These properties have led to many copolymer apphcation developments since 1950. [Pg.191]

The paper presents the experimental and theoretical data regarding the realization and characterization of three liquid-membrane electrodes, which have not been mentioned in the specialized literature so far. The active substances whose solutions in nitrobenzene have constituted the membranes on a graphite rod, are simple complex combinations of the Cu(II) and Ni(II) ions with Schiff base N-[2-thienylmethylidene]-2-aminothiophenol (TNATPh). [Pg.151]

Me3SiNHS020SiMe3, CH2CI2, 30°, 0.5 h, 92-98% yield. Higher yields of trimethylsilyl derivatives are realized by reaction of aliphatic, aromatic, and carboxylic hydroxyl groups with A, <9-bis(trimethylsilyl)sulfamate than by reaction with N,<9-bis(trimethylsilyl)acetamide. ... [Pg.70]


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See also in sourсe #XX -- [ Pg.145 ]




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