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Close relationships

As Bartlett [ ] and Pople have both demonstrated [M], there is a close relationship between the MPPT/MBPT and CC methods when the CC equations are solved iteratively starting with such an MPPT/MBPT-like initial guess for these double-excitation amplitudes. [Pg.2179]

It is noteworthy that it is not obligatory to use a torsional potential within a PEF. Depending on the parameterization, it is also possible to represent the torsional barrier by non-bonding interactions between the atoms separated by three bonds. In fact, torsional potentials and non-bonding 1,4-interactions are in a close relationship. This is one reason why force fields like AMBER downscale the 1,4-non-bonded Coulomb and van der Waals interactions. [Pg.343]

Extension of the streamline Petrov -Galerkin method to transient heat transport problems by a space-time least-squares procedure is reported by Nguen and Reynen (1984). The close relationship between SUPG and the least-squares finite element discretizations is discussed in Chapter 4. An analogous transient upwinding scheme, based on the previously described 0 time-stepping technique, can also be developed (Zienkiewicz and Taylor, 1994). [Pg.92]

To foster a close relationship with the chemical, petroleum, gas, and energy industries and governmental agencies for the exchange of information and knowledge and to ensure that research results and discoveries of significance will be effectively exploited... [Pg.126]

We have seen ( 6.2.3) hat there is a close relationship between the rates of electrophilic substitutions and the stabilities of tr-complexes, and facts already quoted above suggest that no such relationship exists between those rates and the stabilities of the 7r-complexes of the kind discussed here. These two contrasting situations are further illustrated by the data given in table 6.2. As noted earlier, the parallelism of rate data for substitutions with stability data for o"-complexes is not limited to chlorination ( 6.2.4). Clearly, rr-complexes have no general mechanistic or kinetic significance in electrophilic substitutions. [Pg.118]

Figure 8 11 illustrates the close relationship between the E2 and 8 2 pathways for this case and the results cited m the preceding equation clearly show that E2 is faster than 8 2 when a secondary alkyl halide reacts with a strong base... [Pg.348]

The flexibility of the bulk blending system and the close relationship with the farmer allow the bulk blender to provide a number of valuable supplementary services, such as adding herbicides, insecticides, micronutrients, or seeds to the blends bagging blends liming and sampling soil. Consultation services and custom appHcation can also be provided as can sale of anhydrous ammonia or nitrogen solution. [Pg.238]

At least three types of citations in patents can be identified inventors citations found in the patent specification, examiners citations found on issued U.S. patents, and examiners citations found on pubHshed appHcations and granted patents from other countries. A patent inventor cites prior art in order to distance the invention from that art, rather than to show a close relationship. Whereas scientific researchers may want to show how closely they have built on what went before, for an inventor that can suggest anticipation or at least obviousness. Thus, citations within a patent typicaHy try to demonstrate the inadequacies of prior inventions and the uniqueness of the patentee s own work. References tied by this type of citation can be usefiil in developing a picture of the state of the art, but often show sharply differing technologies. [Pg.58]

Monomer Reactivity. The poly(amic acid) groups are formed by nucleophilic substitution by an amino group at a carbonyl carbon of an anhydride group. Therefore, the electrophilicity of the dianhydride is expected to be one of the most important parameters used to determine the reaction rate. There is a close relationship between the reaction rates and the electron affinities, of dianhydrides (12). These were independendy deterrnined by polarography. Stmctures and electron affinities of various dianhydrides are shown in Table 1. [Pg.397]

Curamycin. Curamycin A, presented in Table 2, is the primary component of the culture Streptomjces curacoi (21) and preliminary chemical degradation studies (18) estabUshed it to be an oligosaccharide antibiotic. Later when the complete stmcture was assigned (17,19), the close relationship to flambamycin was evident. Curamycin A melts at 192—199°C. [Pg.144]

Reversible inhibition is characterized by an equiUbrium between enzyme and inhibitor. Many reversible inhibitors are substrate analogues, and bear a close relationship to the normal substrate. When the inhibitor and the substrate compete for the same site on the enzyme, the inhibition is called competitive inhibition. In addition to the reaction described in equation 1, the competing reaction described in equation 3 proceeds when a competitive inhibitor I is added to the reaction solution. [Pg.288]

Enzymes for Liming and Bating. An important discovery (79) for the leather industry was the close relationship between the amount of dermatan sulfate removed and the degree of opening up. Until this discovery, the use of enzymes during the liming and unhairing steps was not considered worthwhile. [Pg.299]

The close relationship of eegonine to tropine is brought out by its Oxidation products, which when chromic anhydride in acetic acid is the agent used are tropinone, CgHijON (p. 74), tropinic acid, CgHi304N (P- 75) and ecgoninic acid, C HnOgN. The latter crystallises from benzene in colourless needles, m.p. 93°, and has been shown by Willstatter and Bode to W-methylpyrrolidone-2-acetic acid, and this was confirmed by Willstatter and Hollander s synthesis of the acid. [Pg.97]

The close relationship existing between ecgonine and tropine is eviden from the following diagrammatic summary of the results of reactions... [Pg.98]

Oxynarcotine, CjjHjaOgN. This alkaloid was separated by Mayer, and later by Beckett and Wright, from crude narceine. It crystallises from hot alcohol in small needles. Its close relationship to narcotine is shown by the formation of cotarnine, C12H15O4N (p. 201), and hemipinic acid when it is oxidised by ferric chloride narcotine under these circumstances furnishing cotarnine and opianic acid. Rabe and McMillan regard oxynarcotine and nomarceine as identical. [Pg.209]

A modification of the formula of a-fagarine just announced establishes its close relationship to the alkaloids of cusparia bark, which like Fagara is derived from a rutaceous genus. ... [Pg.823]

The close relationship of this reaction scheme with that for the Hantzsch protocol becomes obvious upon careful examination. The use of AcOH/NRtOAc as the solvent/nitrogen source has dramatically improved on the experimental ease and yield of this reaction. ... [Pg.309]

VII. There is a close relationship between tautomerism and physical state. [Pg.3]


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See also in sourсe #XX -- [ Pg.26 ]




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