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Positive collapse

It should also be mentioned that although Yablo maintains that the physical properties that realize mental properties (a posteriori) metaphysically suffice for the mental properties, he seems to take no stand on whether there is a disjunction of physical properties, all of the possible physical realizers of the mental property, which is metaphysically necessary for possession of the mental property. Suffice it to note that if there is, and if no two properties can have the same extension in every possible world, then his position collapses to Kim s position, for, then, mental properties that are determinables of physical properties will be physical properties - disjunctive physical properties. The issne, then, would be whether exemplifications of such disjunctive physical properties would he events. (See the discussion of disjunctive events later in the text.)... [Pg.72]

If tire mean Aq is positive tlien tire majority of tire residues are hydrophilic. A description of tire collapsed phase of tire chain requires introducing tliree- and and four-body interaction tenns. Thus, tire total Hamiltonian is... [Pg.2660]

The random-bond heteropolymer is described by a Hamiltonian similar to (C2.5.A3) except that the short-range two-body tenn v.j is taken to be random with a Gaussian distribution. In this case a tliree-body tenn with a positive value of cu is needed to describe the collapsed phase. The Hamiltonian is... [Pg.2663]

The last phase transition is to the soHd state, where molecules have both positional and orientational order. If further pressure is appHed on the monolayer, it collapses, owiag to mechanical iastabiHty and a sharp decrease ia the pressure is observed. This coUapse-pressure depends on the temperature, the pH of the subphase, and the speed with which the barrier is moved. [Pg.532]

Suction Limitations of a Pump Whenever the pressure in a liquid drops below the vapor pressure corresponding to its temperature, the liquid will vaporize. When this happens within an operating pump, the vapor bubbles will be carried along to a point of higher pressure, where they suddenly collapse. This phenomenon is known as cavitation. Cavitation in a pump should be avoided, as it is accompanied by metal removal, vibration, reduced flow, loss in efficiency, and noise. When the absolute suction pressure is low, cavitation may occur in the pump inlet and damage result in the pump suction and on the impeller vanes near the inlet edges. To avoid this phenomenon, it is necessary to maintain a required net positive suction head (NPSH)r, which is the equivalent total head of liquid at the pump centerline less the vapor pressure p. Each pump manufacturer publishes curves relating (NPSH)r to capacity and speed for each pump. [Pg.901]

If desired, dephlegmation (partial collapse of the foam to give reflux) can be accomplished by simply widening the top of the column, provided the foam is not too stable. Otherwise, one of the more positive methods of foam breaking can be employed to achieve dephlegmation. [Pg.2021]

A pump is designed to handle liquid, not vapor. Unfortunately, for many situations, it is easy to get vapor into the pump if the design is not earefully done. Vapor forms if the pressure in the pump falls below the liquid s vapor pressure. The lowest pressure occurs right at the impeller inlet where a sharp pressure dip oeeurs. The impeller rapidly builds up the pressure, which collapses vapor bubbles, eausing cavitation and damage. This must be avoided by maintaining sufficient net positive suetion head (NPSFl) as specified by the manufacturer. [Pg.106]

Obviously the structures and yields of Birch reduction products are determined at the two protonation stages. The ring positions at which both protonations occur are determined kinetically the first protonation or 7t-complex collapse is rate determining and irreversible, and the second protonation normally is irreversible under the reaction conditions. In theory, the radical-anion could protonate at any one of the six carbon atoms of the ring and each of the possible cyclohexadienyl carbanions formed subsequently could protonate at any one of three positions. Undoubtedly the steric and electronic factors discussed above determine the kinetically favored positions of protonation, but at present it is difficult to evaluate the importance of each factor in specific cases. A brief summary of some empirical and theoretical data regarding the favored positions of protonation follows. [Pg.17]

Formation of 84 upon reaction of 82 with KH in DMF without using NaOMe is explained in terms of the initial hydride addition to 82 at the 3 position, forming 101 and a methoxide ion (Scheme 14). The newly bom methoxide ion then adds to another molecule of 82 to generate 102 and another methoxide ion. The process is repeated as a chain reaction, while 101 and 102 collapse to 83 and 84, respectively. [Pg.117]

In many cases, however, the ortho isomer is the predominant product, and it is the meta para ratio which is close to the statistical value, in reactions both on benzenoid compounds and on pyri-dine. " There has been no satisfactory explanation of this feature of the reaction. One theory, which lacks verification, is that the radical first forms a complex with the aromatic compound at the position of greatest electron density that this is invariably cither the substituent or the position ortho to the substituent, depending on whether the substituent is electron-attracting or -releasing and that when the preliminary complex collapses to the tr-complex, the new bond is most likely to be formed at the ortho position.For heterocyclic compounds such as pyridine it is possible that the phenyl radical complexes with the nitrogen atom and that a simple electronic reorganization forms the tj-complex at the 2-position. [Pg.143]

Consider the possibility that the reaction proceeds in stages (a) addition of C1 to a vacant axial position, (b) loss of any equatorial Cl", (c) collapse of this structure to the stable square-planar geometry. This sequence is shown ... [Pg.176]

In the pioneering work the same information was extracted from the extremum position assuming it is independent of y [143]. This is actually the case when isotropic scattering is studied by the CARS spectroscopy method [134]. The characteristic feature of the method is that it measures o(ico) 2 not the real part of Ko(icu), as conventional Raman scattering does. This is insignificant for symmetric Lorentzian contours, but not for the asymmetric spectra observed in rarefied gas. These CARS spectra are different from Raman ones both in shape and width until the spectrum collapses and its asymmetry disappears. In particular, it turns out that... [Pg.106]

Direct formation of 51 would have placed the deuterium exclusively at the 3 position (79). The observed scrambling has been explained by the prior formation of ion 50, which rapidly rearranges to 51 and yields the observed cyclobutanone products (79). The involvement of ion 51 as an intermediate is surprising, for it would be expected to be highly strained. A more likely intermediate may be a bridged Species such as 56, which upon collapse with... [Pg.230]


See other pages where Positive collapse is mentioned: [Pg.606]    [Pg.153]    [Pg.606]    [Pg.153]    [Pg.2663]    [Pg.2785]    [Pg.170]    [Pg.33]    [Pg.170]    [Pg.668]    [Pg.448]    [Pg.92]    [Pg.200]    [Pg.415]    [Pg.53]    [Pg.340]    [Pg.354]    [Pg.174]    [Pg.252]    [Pg.35]    [Pg.517]    [Pg.728]    [Pg.460]    [Pg.460]    [Pg.461]    [Pg.172]    [Pg.820]    [Pg.488]    [Pg.142]    [Pg.149]    [Pg.429]    [Pg.133]    [Pg.408]    [Pg.415]    [Pg.766]    [Pg.455]    [Pg.470]    [Pg.149]   
See also in sourсe #XX -- [ Pg.606 ]




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