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Many formalism

Many formally endergonic biochemical processes become exergomc when they are coupled mechanistically to the hydrolysis of ATP... [Pg.1188]

How many formal checkpoints does this system require For example, a system for maintaining MSDSs may require multiple reviews of each new entry, or be consolidated as a single person s responsibility. Results may be forwarded to a centralized checkpoint, or may remain at the facility or division level. [Pg.68]

We might properly refer to this value as the apparent Peclet number, because by many formal definitions the Peclet number accounts for the relative importance of advection and molecular diffusion, without mention of hydrodynamic dispersion. [Pg.294]

In addition to the aforementioned syntheses of various carbazole-l,4-quinone alkaloids, many formal syntheses for this class of carbazole alkaloids were also reported. These syntheses involve the oxidation of the appropriate 1- or 4-oxygenated-3-methylcarbazoles using Fremy s salt (potassium nitrosodisulfonate), or PCC (pyridinium chlorochromate), or Phl(OCCXI F3)2 [bis(trifluoroacetoxy)iodo]-benzene. Our iron-mediated formal synthesis of murrayaquinone A (107) was achieved starting from murrayafoline A (7) (see Scheme 5.34). Cleavage of the methyl ether in murrayafoline A (7) and subsequent oxidation of the resulting intermediate hydroxycarbazole with Fremy s salt provided murrayaquinone A (107) (574,632) (Scheme 5.113). [Pg.265]

Nuclear magnetic resonance (NMR) is another spectroscopic technique that has many formal similarities to EPR. It is widely used for product analysis, as in studies leading to the development of electrosynthetic methods. The intrinsic sensitivity of NMR is several orders of magnitude lower than that of EPR, making simultaneous NMR-electrochemical experiments unattractive. [Pg.902]

For many formal considerations this compact operator formulation is more convenient. For example, it is possible to write a formal solution of this equation in the form... [Pg.185]

Given any P-dimensional vector b, the A-dimensional vector p b lies in the kernel of = b = 0. This, as will be seen, has important consequences in the theory of equilibrium. It is also important to realize that a description of the stoichiometry in terms of the condition = is in many senses equivalent to a description in terms of a, and in many formal manipulations it may be preferable when the number of species and/or reactions becomes very large, because the dimensions of stay at P no matter how complex the mixture may be. [Pg.6]

Abstract. The Chebyshev operator is a diserete eosine-type propagator that bears many formal similarities with the time propagator. It has some unique and desirable numerical properties that distinguish it as an optimal propagator for a wide variety of quantum mechanical studies of molecular systems. In this contribution, we discuss some recent applications of the Chebyshev propagator to scattering problems, including the calculation of resonances, cumulative reaction probabilities, S-matrix elements, cross-sections, and reaction rates. [Pg.217]

IR data of (Ph3PAu)2( r-dec), where dec = l,12-bis(ethynyl)-l,12-dicarba-rVo.vo-dodeca-borane, 1,12-(HC=C)2-1,12-C2B10Hio, include vC=C of the Au C=C C unit at 2146 cm-1, with vBH at 2666 and 2614 cm-1.75 SERS data for C6o adsorbed on an aqueous gold colloid show band splitting and the presence of many formally forbidden bands due to lowered symmetry.76 For C60 and C70 adsorbed on gold nanoparticles similar data are consistent with metal coordination via pentagonal faces.77... [Pg.305]

It is natural to exploit the commutation relations for quantum chemical considerations, as they are the traditional background of the algebraic structure of quantum theory. There are many formal relations like... [Pg.33]

You cherish your freedom, long for adventure, and take Don t fence me in as your personal creed. It goes without saying that relationships are an issue. When a relationship challenges you or introduces you to a wider world, you re intrigued and excited. Unpredictability attracts you. But too many rules, too many formal dinners, and too much domesticity drive you to despair. [Pg.226]

This allows us to carry out many formal manipulations (perturbation theory, projection operator techniques, selective averaging over bath degrees of freedom, etc.) in a straightforward way. We shall be interested in calculating the polarization at position r at time t. This is given by the expectation value of the dipole operator V ... [Pg.170]

It cannot yet be claimed that the experimental evidence for such distortions from tetrahedral coordination is so well established as for the octahedral case, but this is largely attributable to the comparative rarity of structures in which transition-metal ions occur in a tetrahedral environment. There appear to be no examples of tetrahedral coordination about d3 and d ions, and only fragmentary information is available for d8 and d9 ions. It may be recalled that tetrahedral coordination was anticipated by Pauling 11 A) for paramagnetic 4-covalent complexes of nickel(II) on the grounds that, since all the d orbitals are occupied by electrons from the metal, the covalent bonding must occur through sp3 hybridized orbitals. It is now known that many formally 4-covalent complexes are, in fact,... [Pg.27]

There are many formal methods for user interface evaluation in the Uteratnre. A selection of some of the more common approaches which are snitable for HIT are set ont below. [Pg.251]

This expression is used to characterize the complexation properties of macroligands such as humic acids, proteins, etc. (see for instance [15-17]). There are many formalized models of complexation [18-20] in which expressions for the constant of formation considering the different forms of complexes are suggested. However, they are inconvenient for practical use and require a multiplex calculation procedure. [Pg.76]

Most practitioners define "Fail-Safe" for an instrument as a failure that causes a "false or spurious" trip of a safety instrumented function unless that trip is prevented by the architecture of the safety instrumented function. Many formal definitions have been attempted that include "a failure which causes the system to go to a safe state or increases the probability of going to a safe state." This definition is useful at the system level and includes many cases where redundant architectures are used. [Pg.85]

Note that by convention, the placement of the operator symbols depends on the monadic/dyadic property of the operator. This allows combining a dyadic operator with two monadic operators as seen in many Formal Graphs (mainly for adding contributions of several links). [Pg.6]

Generalized operators. Without departing from the restriction to the Euclidean space adopted for pedagogical reasons, Table 5.4 the generalization to other spaces (discrete space in particular) made possible by using different symbols. They will be used in many Formal Graphs later on as they apply to Euclidean space too. [Pg.129]

An interesting approach to the quantum mechanical description of many-electron systems such as atoms, molecules, and solids is based on the idea that it should be possible to find a quantum theory that refers solely to observable quantities. Instead of relying on a wave function, such a theory should be based on the electron density. In this section, we introduce the basic concepts of this density functional theory (DFT) from fundamental relativistic principles. The equations that need to be solved within DFT are similar in structure to the SCF one-electron equations. For this reason, the focus here is on selected conceptual issues of relativistic DFT. From a practical and algorithmic point of view, most contemporary DFT variants can be considered as an improved model compared to the Hartree-Fock method, which is the reason why this section is very brief on solution and implementation aspects for the underlying one-electron equations. For elaborate accounts on nonrelativistic DFT that also address the many formal difficulties arising in the context of DFT, we therefore refer the reader to excellent monographs devoted to the subject [383-385]. [Pg.313]

There are many formal resemblances between the oxidation of saturated hydrocarbons including polymers such as polyethylene, diene rubbers such as natural rubber and low molecular weight analogues such as squalene. The principal features common to these systems are as follows ... [Pg.261]

There are many formal roles under the MHA ( indicates 2007 amendments)... [Pg.187]

We choose LNT [5] as target specification language which derives from two standards Lotos [1] and E-Lotos [2]. This choice is justified by the expressiveness and richness of LNT. It provides expressive enough operators for data and behaviour description and it has a user-friendly notations to simplify the specification writing. Indeed, LNT is a CADP [6] (Construction and Analysis of Distributed Processes) input language. It is a popular formal verification toolbox that implements many formal methods. [Pg.147]

At the beginning of this section it is important to point out that the theoretical treatment we will briefly discuss now is sometimes called semiclassical just because the correlation functions are classical. A quantum mechanical treatment has been proposed (2, p. 284) which presents many formal similarities to the semiclassical treatment but which fundamentally differs from it by the way the correlation functions are defined (in terms of time-dependent operators and not of time functions). This distinction is rarely done in review articles about relaxation where the semiclassical approach is generally presented as the only way to handle the problem. To introduce the correlation functions and spectral densities, we will consider a spin system characterized by eigenstates a, b, c. and corresponding energies E, E. A perturbation, time-dependent Hamiltonian H(t) acts on this system. H(t) corresponds to the coupling of the spin system with the lattice. We shall make the assumption that H(t) can be written as a product A f(t). [Pg.76]


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See also in sourсe #XX -- [ Pg.14 ]




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