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THEORY WITHOUT DETAILED

Textile clothing static charges, 394 Theory without detailed thought, 394 Thermal explosions, 394 Thermal stability of reaction mixtures and systems, 394 Thermite reactions, 395 Thermochemistry and exothermic decomposition, 396 Thiatriazoles, 400 Thionoesters, 401 Thiophenoxides, 401 Thorium furnace residues, 401 Tollens reagent, 401 Toxic hazards, 402 Trialkylaluminiums, 402 Trialkylantimony halides, 403 Trialkylbismuths, 403... [Pg.2641]

Without going into this theory in detail, let us reproduce here the equation proposed by Rubingh for the activity factor of surfactant species making up mixed micelles in a binary system ... [Pg.276]

The Kuhn model is presented in detail (and in parts mathematically justified) in the articles referred to above. It is unclear why Kuhn s ideas have not always received due attention in the literature in comparison with other theories. Without going into detail, some features will be mentioned briefly. [Pg.229]

The I2 system has been investigated experimentally, theoretically, and computationally by several groups, as a prototype for the study of dissociation and recombination dynamics influenced by the interactions with a surrounding solvent or cluster of solvent molecules[9],[36]-[41]. The system can be effectively modelled by two VB states[9],[41], which allows a focus on several key aspects of the implementation of the theory, without being hindered by the complexity of a multistate calculation. The implementation steps are conveniently collected in the flow chart in Table 1, to which the reader is referred to for a comprehensive overview of our strategy. All the details of the calculation are reported in BH-II. The effective wave function for the I2 reaction system can be written as... [Pg.267]

The theory again accords the observation that dimerisation is almost invariably a photochemical process. Such conclusions can also be reached qualitatively without detailed calculations, but for precise estimations of the energies involved in the more complex cases, elaborate calculations are necessary. [Pg.38]

The adiabatic approximation is one of the keystones on which the theory of electron tunneling is based (see Sect. 2). In particular, the matrix element for the transition between the initial and the final electron states contain the adiabatic wave functions of the donor and acceptor. Adiabatic approximation is known [25] to have a very high degree of accuracy. Because of this the non-adiabatic effects have been neglected until recently in the theory of electron tunneling without detailed analysis of whether this can actually be done. In the present section we shall try to fill in this blank and to discuss to what extent the non-adiabatic effects can influence the process of electron tunneling. [Pg.100]

The treatment of INEPT by the density matrix is more satisfactory than the development in Section 9.6 in that it follows in a logical way from the initial theory without the need to pull together in an ad hoc way certain features from classical and quantum mechanics. However, we have not really gained any new insights into the physics of the processes. Let s now look at some aspects in more detail. [Pg.301]

The correlation between activity coefficient and ionic strength can be deduced from the quantitative relationships of the Debye-Hiickel-Onsager theory. Without giving details of this deduction it is interesting to quote the final result ... [Pg.23]

States away from global equilibrium are called the thermodynamic branch (Figure 2.2). Systems not far from global equilibrium may be extrapolated around equilibrium state. For systems near equilibrium, linear phenomenological equations may represent the transport and rate processes. The linear nonequilibrium thermodynamics theory determines the dissipation function or the rate of entropy production to describe such systems in the vicinity of equilibrium. This theory is particularly useful to describe coupled phenomena, and quantify the level of coupling in physical, chemical, and biological systems without detailed process mechanisms. [Pg.54]

In principle, it would be possible to determine the outcome of any chemical reaction if (a) The reaction mechanisms were known in detail, i.e. if all equilibrium constants and all rate constants of intermediary steps were known and (b) the initial concentrations of the reactants and the activity coefficients of all species involved were perfectly known. However, this is never the case in practice. It would be impossible to derive such a model by deduction from physical chemical theory without introducing drastic assumptions and simplifications. A consequence of this is, that the precision of any detailed prediction from such hard models will be low. In addition to this, physical chemical models rarely take interaction effects between experimental variables into account, which means that, in practice, such models will not be very useful for analysing the influence of experimental variables on synthetic operations. [Pg.33]

The series of redox reactions discussed in this chapter indicate that frontier MOT is a powerful approach and is able, without detailed quantum-mechanical computations (on which the theory is based), to predict the following ... [Pg.195]

Although the problem defined by (3-95) and (3-96) is time dependent, it is linear in uJ and confined to the bounded spatial domain, 0 < r < 1. Thus it can be solved by the method of separation of variables. In this method we first find a set of eigensolutions that satisfy the DE (3-95) and the boundary condition at r = 1 then we determine the particular sum of those eigensolutions that also satisfies the initial condition at 7 = 0. The problem (3-95) and (3-96) comprises one example of the general class of so-called Sturm-Louiville problems for which an extensive theory is available that ensures the existence and uniqueness of solutions constructed by means of eigenfunction expansions by the method of separation of variables.14 It is assumed that the reader is familiar with the basic technique, and the solution of (3-95) and (3-96) is simply outlined without detailed proofs. We begin with the basic hypothesis that a solution of (3-95) exists in the separable form... [Pg.137]

Alternatively, it might be that any well-defined density functional necessarily has a Frechet functional derivative, so that the locality property is inherent in the definition vF (r) = 8F/8p [18,19] and can be assumed without detailed proof. The mathematical object so defined must be proven to exist if this definition is to have any meaning. Counterexamples show that a local functional derivative does not exist in cases for which it can be tested. Either the theory must be abandoned or the definition must be generalized. [Pg.9]

The UNF s biological research catalysed many important discoveries in other laboratories, as well as prompting re-thinks in general enzymology, microbial physiology, genetics and evolutionary theory. In the space available I can only touch upon a few highlights without detailed citations (see Section 6). [Pg.238]

In summary, we are primarily concerned with two classes of reactions (/) bimolecular reactions with a steep chemical barrier or possibly a steric constraint to reaction, and (2) recombination reactions in which motion of the atoms in the strongly attractive well must be treated. In both instances we assume that only the strongly repulsive solute-solvent and solvent-solvent forces need to be taken into account. We present a type of kinetic theory that is capable of handling more general cases, but the two reaction classes suffice to illustrate the use of the theory without overly elaborate calculations. Our goal is a detailed treatment of the effects of solvent dynamics on the reaction. [Pg.96]

In 1977 Krishnamurthy and Subramanian published an exact theoretical analysis of FFF [19], based on their generalized dispersion theory. Without touching on the details of a complicated mathematical treatment, with the aid of which they solved the problems of both the separation and dispersion processes that occur in the FFF channel during the complete separation from the injection to the elution, let us only say in general that their solution makes it possible to explain some experimental artefacts in detail. These artefacts could not be explained by means of the non-equilibrium theory of FFF mentioned above, which is based on some asymptotic assumptions. Perhaps the most important discrepancy between the theory and the experimental data is that the zone spreading that is observed is considerably larger than the spreading predicted by the theory. [Pg.503]


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