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Non isolation

Sample calculations for designing a 2500 A non-isolated phase aluminium busbar system 28/891... [Pg.857]

The design criteria and construction details of this system are totally different from those of a non-isolaled phase bus system. This type of enclosure is therefore dealt separately in Chapter 31. [Pg.861]

The proximity effect does not end here. It still has some far-reaching consequences in terms of unequal voltage drops in different phases at the same time. This is more so on large LT current-carrying, non-isolated bus systems of 2000 A and above, resulting in an unbalance in the supply voltage, as discussed below. [Pg.882]

Part V Bus systems in including metal-enclosed non-isolated and isolated phase bus systems... [Pg.990]

Introduction Types of metal-enclosed bus systems Design parameters and service conditions for a metal enclosed bus system Short-circuit effects Service conditions Other design considerations Skin effect Proximity effect Sample calculation for designing a 2500 A non-isolaled phase aluminium busbar systern... [Pg.998]

Criterion (1) is seen to be identical with Horstmann s principle it has been largely employed in the treatment of equilibria by Planck. It is, however, not always convenient in application because the systems which actually occur in practice are not isolated we shall therefore modify the relation so as to make it suitable for non-isolated systems. In this investigation we shall recover the first general method for determining the conditions of equilibrium—the principle of dissipation of energy. [Pg.95]

A more direct access to the unstable and non isolated sulfonium ylides 58a- c is the reaction of diisopropyl diazomethylphosphonate 57 with allylic sulfides, catalyzed by Cu(II), Rh(II) [39], or ruthenium porphyrins.[40] For example, the a-phosphorylated y,d-unsaturated sulfides 59-61 are obtained through the [2,3] -sigmatropic rearrangement of 58a-c. This method allows the use of a greater variety of starting allylic sulfide substrates, such as 2-vinyl tetrahydrothiophene, or propargylic sulfides (Scheme 15). [Pg.173]

The modification of molecular conformation from the highly strained non-isolable dimer molecule to the V-shaped dimer molecule (6 OPr-dimer) is explained in terms of relaxation of the strain energy due to the bond angle in the non-isolable dimer, which accumulated during the cyclobutane formation. Therefore, strictly speaking, the process going from the non-isolable dimer into the V-shaped dimer (6 OPr-dimer) is not a... [Pg.140]

Transfer hydrogenation of aldehydes with isopropanol without addition of external base has been achieved using the electronically and coordinatively unsaturated Os complex 43 as catalyst. High turnover frequencies have been observed with aldehyde substrates, however the catalyst was very poor for the hydrogenation of ketones. The stoichiometric conversion of 43 to the spectroscopically identifiable in solution ketone complex 45, via the non-isolable complex 44 (Scheme 2.4), provides evidence for two steps of the operating mechanism (alkoxide exchange, p-hydride elimination to form ketone hydride complex) of the transfer hydrogenation reaction [43]. [Pg.31]

The thiolato complex 97 that was postulated as the active catalytic species in the reaction was prepared from 96 and the thiol in the presence of NEtj. Certain analogues of 97 (NHC = Mes, SIMes, IPr, SIPr R = Ph) have also been independently synthesised, isolated and fully characterised. A plausible mechanism for the hydrothiolation involves insertion of the alkyne into the Ni-SR bond forming the (non-isolable) p-thioalkenyl complex, from which the product can be released via alkanolysis of the Ni-C bond by the thiol and regeneration of the active catalyst 97 [84]. [Pg.45]

The readily available, nonracemic indoloquinolizidine template 471 has been studied as a substrate for the construction of frameworks related to bioactive natural products. The lithiated dithiolane 472 served a dual role in its reaction with 471, both as a nucleophile giving the non-isolated intermediate 473, and, in the same pot, as an electrophile during the quench process. This reaction afforded compound 474 as a single diastereomer <2006TL1961>. [Pg.69]

From the results with the isolable ylides 350, it can be concluded that the fate of less stable, non-isolated sulfonium ylides depends dramatically on their respective substituents 336,338). Thus, the outcome of these reactions is programmed at the ylide stage and not during interaction of a presumed metal carbene with the sulfur-containing substrate. [Pg.212]

The first observation of the uncommon phenomenon of desmotropy in seven-membered heterocycles was reported for the prototropic annular tautomers 128 and 129. These dihydro-4,1-benzothiazepines, which were prepared (via the non-isolated intermediates 130 and 131 from the fused azetidinone 127 on treatment with NaOEt), could be isolated in pure form by column... [Pg.455]

The Regulation as a whole does not apply to radioactive substances, genetically modified organisms, substances in transit and non-isolated chemical intermediates. In addition, certain other categories of substance are exempt from registration (Table 8). [Pg.11]

Torres et al. (2006) reported a novel microwave processing technique to produce biodegradable scaffolds for tissue engineering from different types of starch-based polymers. Potato, sweet potato, com starch, and non-isolated amaranth and quinoa starch were used along with water and glycerol as plasticizers to produce porous stmctures. Figure 16.1 shows the manufacturing procedure of microwaved starch scaffolds. [Pg.451]

Reports of pericyclic cyloadditions to other azepine systems are rare. Addition to the diene system of 6,7-dihydro-l//-azepines occurs readily with DMAD (72CPB1740) and with N-phenylmaleimide (73JA7320). The 5,5a-dihydro-3-benzazepin-2-one (157), a suspected but non-isolable intermediate in the formation of l,2,4,5-tetrahydro-3//-3-benzazepine-2,4-diones by photoaddition of diphenylketen to amino-2//-azirines, has been trapped in the photolysate by N-phenyl-1,3,4-triazoline-2,4-dione as the [4+2]tt adduct (158). Its structure was confirmed by X-ray analysis (80JOC2951). [Pg.522]

This index lists over 4000 heterocylic parent ring systems and has been compiled from 20,000 occurrences of those systems and their derivatives in Volumes 1-7 in the text, tables and displayed formulae, equations and schemes. Heterocycles have been included when they occur as a starting material or as a product, but not when they are reported as a non-isolable intermediate or as a solvent. [Pg.927]

The reaction of A -arylbenzamidoximes (245) with nitrile oxides in refluxing toluene has been reported to lead mainly to benzotriazines (247), the formation of which has been explained285 by postulating the occurrence of an unusual [3,5]-rearrangement of the non-isolated 1 1 adduct (246) (see Scheme 57). [Pg.530]


See other pages where Non isolation is mentioned: [Pg.887]    [Pg.891]    [Pg.938]    [Pg.239]    [Pg.102]    [Pg.140]    [Pg.141]    [Pg.151]    [Pg.116]    [Pg.132]    [Pg.502]    [Pg.367]    [Pg.11]    [Pg.305]    [Pg.208]    [Pg.46]    [Pg.56]    [Pg.355]    [Pg.121]    [Pg.83]    [Pg.200]    [Pg.499]    [Pg.138]    [Pg.139]    [Pg.281]    [Pg.107]    [Pg.107]    [Pg.171]    [Pg.176]    [Pg.196]   
See also in sourсe #XX -- [ Pg.8 , Pg.9 ]




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