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Additional restrictions

In certain types of problem there are additional restrictions on the system, and the effect of each of these is equivalent to an extra equation between the variables and thus reduces the number of degrees of freedom by unity. [Pg.188]

As a preliminary example consider a liquid A which is in contact with its vapour and also with the atmosphere at its standard pressure. Such a system may be discussed in several different ways  [Pg.188]

The several alternative ways of considering the problem are thus entirely equivalent. [Pg.188]

In general, what we have called an additional restriction implies that the system under discussion is of a special type, for example, that the pressure has a certain value or that the concentrations of two species in a particular phase are in a fixed ratio. An important instance occurs in the case of ionic solutions on account of the powerful Coulombic forces, the concentrations of the ions must be such that the solution as a whole is electrically neutral. [Pg.188]

It is evident that whenever a restriction is operative, it is equivalent to taking the number of components as being one less than is given by the relation C=N—R. For example, in the case of ionic solutions the number of effective components is JV—jB — 1, on account of the electroneutrality restriction.f [Pg.188]


If the m Equations (7-1) are considered independent, additional restrictions must be imposed as... [Pg.112]

If one or two of the indices are zeros, there may be additional restrictions. We have seen that a 2jscrew axis parallel to the c axis of the unit cell produces pairs of atoms at x, y, z) and -x, -y, z + k). From equation... [Pg.1374]

The second step, the so called generation, created only those structures which complied with the given constraints, and imposed additional restrictions on the compounds such as the number of rings or double bonds. The third and final phase, the tester phase, examined each proposed solution for each proposed compound a mass spectrum was predicted which was then compared with the actual data of the compound. The possible solutions were then ranked depending on the deviation between the observed and the predicted mass spectra. [Pg.480]

The 3D pharmacophore search with C(5)ROL in the Biochemical Pathways database provided 13 different molecules as hits. To further limit the number of hits, the additional restriction was imposed that the hits should have only two hydrogen... [Pg.565]

In addition, restrictions on industrial air emissions under the Clean Air Act (CAA) as amended in 1977, the Clean Air Act Amendments (CAAA) of 1990, and other state and local statutes and regulations have universal impact on the storage of toxic materials, with direct and significant effects on the design and operation of toxic material storage facilities. Whereas the primary factors which once determined how air emissions from storage tanks were handled were fire protection and loss prevention, in recent years environmental protection concerns nearly always determine the extent and nature of the air emission controls required to be installed. [Pg.2310]

Since the unit exhausts to atmosphere with no additional restrictions, the total pressure drop s ... [Pg.264]

The factors affecting railway diesels apply also to marine diesels but with the additional restriction that the inhibitors must not present a toxicity hazard when the cooling system is associated with equipment for producing drinking water. This is because of the possibility of accidental leakage between the two systems. [Pg.790]

We have imposed an additional restriction on the operation of the pilot plant methanation section. We must have accurate and continuous... [Pg.141]

One example of a structure (8) is the space of polynomials, where the ladder of subspaces corresponds to polynomials of increasing degree. As the index / of Sj increases, the subspaces become increasingly more complex where complexity is referred to the number of basis functions spanning each subspace. Since we seek the solution at the lowest index space, we express our bias toward simpler solutions. This is not, however, enough in guaranteeing smoothness for the approximating function. Additional restrictions will have to be imposed on the structure to accommodate better the notion of smoothness and that, in turn, depends on our ability to relate this intuitive requirement to mathematical descriptions. [Pg.175]

Figure 3 demonstrates the simplifications in the spectrum of an optimized laser pulse that can be achieved through the application of the sifting technique [see Fq. (7)]. The excitation efficiency of the pulse is only minimally reduced due to the additional restrictions imposed in the sifting procedure. The example used in this case is for a vibrational-rotational excitation process, H2(v = 0,7 = 0) H2(v =1,/ = 2). [Pg.62]

Part 70 Color additives — This part includes a definition of a color additive, restrictions on use of color additives, packaging and labeling requirements, and safety evaluation of color additives. [Pg.576]

The form of the solutions that one obtains for reactions of this type is dictated by the relative values of the four reaction orders. For some choices of these orders it is not possible to obtain simple closed form solutions to these rate equations unless one places additional restrictions on the initial composition of the reaction mixture. The three possible-cases are discussed below. [Pg.143]

Now we place on our programs two additional restrictions on the use of variables in CALLs. They are ... [Pg.289]

The template synthesis by the method of Mann et al. is limited to large objects because of the nanoparticle dimension. There is also an additional restriction on its widespread use caused by the nanoparticle being stable only in deionized water with pH between 10 and 11. [Pg.84]

Third, processing times may require special modeling in chemical industry. While in discrete manufacturing processing times for a certain lot are usually dependent on the lot size, i.e., the number of units to be produced, this is often not true in the chemical industry. Here, processing times are often constant, irrespective of whether a reactor is filled to 70% or 90% of its capacity. This is often referred to as batch production [5], On the other hand, the quality of the material produced may depend on resource utilization. Certain reactions may not even be feasible, if a minimum bound of the procured material is not exceeded. This implies additional restrictions regarding the resource utilization level on the planning situation. [Pg.242]

Journal of Coatings Technology 71, No.896, Sept. 1999, p.14 EUROPEAN COMMISSION FOREGOES ADDITIONAL RESTRICTIONS ON CADMIUM PIGMENTS USED IN PLASTICS... [Pg.88]

Underground injection is the subsurface emplacement of fluids through a well or hole whose depth is greater than its width. Injected fluids can include hazardous waste, brine from oil and gas production, and certain mining processes. An injection well can include a septic well, cesspool, or dry well. The SDWA allows regulation of UIC to protect usable aquifers from contamination, with additional restrictions and controls under the 1984 Amendments to RCRA. [Pg.23]

Finally, it should be considered that additional non-natural functional groups, which are often incorporated in the lipidated peptides for biological studies such as fluorophores or photoactive groups, typically lead to additional restrictions for the synthesis protocols. [Pg.539]

Incorporation of a second functional group within the molecule should lower AN but would entail additional restrictions in the transition state. Orientation of the second group would make TAS more unfavourable, assuming that AN is a measure of potential... [Pg.106]

Additional restrictions on supply are imposed by the Misuse of Drugs Act 1971 and the Misuse of Drugs Regulations. Substances that have a potential for abuse are scheduled under three categories. Class A, B and C. [Pg.531]

Essentially, sublattice models originate from the concepts of Temkin (1945) who proposed that two separate sublattices exist in a solid-state crystal for cations and anions. The configurational entropy is then governed by the site occupation of the various cations and anions on their respective sublattices. When the valence of the cations and anions on the sublattices are equal, and electroneutrality is maintained, the model parameters can be represented as described in Section 5.4.2. However, when the valence of the cations and anions varies, the situation becomes more complex and some additional restrictions need to be made. These can be expressed by considering equivalent fractions (/) which, for a sublattice phase with the formula (/, . .. )(M"", . ..), are given by... [Pg.131]

In order to obtain a theoretical expression for the EMF corresponding to Eq. (2), the integral Eq. (6), which describes the diffusion potential, must be evaluated. To this end, additional restrictions must be incorporated, beside those already listed in Table 5. Table 6 contains a com-... [Pg.128]

Schedule (C-V) V Very limited abuse potential prescribing regulations often same as for uncontrolled medications some states have additional restrictions. [Pg.442]

Let us conclude this section with the intriguing observation of the absence of the a (7t(ag, b f)) contribution in the Nls NEXAFS spectra of both neutral TCNQ and TTF-TCNQ. Let us recall the absence of precisely the Og and b u contributions in the CI5 spectra of TTF discussed above. However, the Cls NEXAFS spectrum of TCNQ shows some intensity in the a (7r(ag, b f)) region [between n a , bif) and TT (jr(b3g, af>) + a n b g, 2u))]- This is due to the signihcant 6 -contribution from carbon for neutral TCNQ while nitrogen contributes negligibly. Thus, it seems that in addition to the intra-atomic selection rules there are additional restrictions apparently symmetry-related in MOMs like those discussed here. This unexplained phenomenon certainly calls for both theoretical and experimental future work. [Pg.268]

The extent to which any given direct mechanisms may be combined without cycle formation can be determined by noting whether such combinations contain irreducible cycles. The latter are the cycles with a minimal number of steps which characterize a given system. They can be determined by a procedure that is analogous to that for finding direct mechanisms [Sellers (9a). For a multiple overall reaction, the relative degrees of advancement for each of the simple overall reactions chosen as a basis introduce additional restrictions on the allowable cycle free combinations) [Sellers (9b)]. [Pg.283]

Smith (47) and Bjornbom (48) have discussed the introduction of restrictions into equilibrium calculations in addition to the elemental abundance constraints. Often only a restricted set of terminal species is chosen, but it would seem logical in choosing such additional restrictions to revert to Gibbs original idea of specifying possible reactions as well as possible species. The choice of elementary reactions, rather than of overall reactions with complicated stoichiometry, would be simplified by modern developments in theoretical chemistry and surface science. [Pg.319]

To obtain theoretical expressions for E corresponding to (1), additional restrictions must be incorporated, besides those given in the preceding list. Assuming cations Iz+ and Jz + to be of the same charge z+ and the formation of any or all l n (n = 1, 2,..., N, respectively, M) cation-carrier complexes possible, the expressions given in Table 11 are obtained.33 These are based on the assumption that the concentration [cs(x)] of the uncomplexed carrier S in the liquid membrane remains constant and that... [Pg.290]

Inserting the forms of the functions f,g,h obtained into (80) with the subsequent substitution of the latter expression into the corresponding ansatz (53)—(55) yields invariant solutions of the SU(2) Yang-Mills equations (46). Note that solutions of systems 5, 8.1, 14.2, 15.2, 16, and 19-21, with g = 0, give rise to Abelian solutions of the Yang-Mills equation, namely, to solutions satisfying the additional restriction x Av = 0. Such solutions are of low interest for physical applications and are not considered here. Below we give the full list of non-Abelian invariant solutions of Eqs. (46) ... [Pg.321]


See other pages where Additional restrictions is mentioned: [Pg.698]    [Pg.250]    [Pg.762]    [Pg.53]    [Pg.1302]    [Pg.285]    [Pg.672]    [Pg.817]    [Pg.43]    [Pg.48]    [Pg.53]    [Pg.195]    [Pg.55]    [Pg.291]    [Pg.805]    [Pg.108]    [Pg.69]    [Pg.31]    [Pg.23]    [Pg.48]    [Pg.80]    [Pg.20]   


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