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81.
Thermally stimulated recovery behaviour of amorphous polymers is described in terms of a continuous distribution of sharply defined elementary softening processes in the polymer. It is proposed that each of these elementary processes is the result of a co-operative site-change mechanism. On exceeding the activation temperature for the process, the viscoelastic time constants fall abruptly by many orders of magnitude, as opposed to following an Arrhenius-type law. The implications of this type of behaviour are discussed.
Prof. Schwarzl zum 60. Geburtstag gewidmet. 相似文献
82.
J. D. Owen 《Acta Crystallographica. Section C, Structural Chemistry》1983,39(5):579-582
83.
84.
M. Ambrosio G. Anzivino G. Barbarino G. Carboni V. Cavasinni T. Del Prete P.D. Grannis D. Lloyd Owen M. Morganti G. Paternoster S. Patricelli M. Valdata-Nappi 《Physics letters. [Part B]》1982,115(6):495-502
We measured the differential cross section for p?p and pp elastic scattering in the momentum-transfer range 0.01 <|t| < 1.0 GeV2 at the CERN Intersecting Storage Rings with center-of-mass energy . Fitting the differential cross section with an exponential [Aexp (bt)], we found for |t| < 0.05 GeV2, whilst for |t| > 0.09 GeV2, . Using the optical theorem, we obtained for the total cross section and, by integrating the differential cross section, we obtained for the total elastic cross section . Calculations of σtot combining elastic-rate and total-rate measurements are also given. All of these measurements were also performed for pp scattering at the same energy, and the results for both reactions are compared. 相似文献
85.
The direct irradiation of the monomethoxybarrelene 8 gives cyclooctatetraene product 18 (Φ = 0.075) via the anti-Epiotis aromatic-vinyldiester [2π+2π] bridging route, and two semibullvalenes 16 (Φ = 0.075) and 17 (Φ = 0.075) from di-π-methane rearrangements initiating from vinyl-vinyldiester bridging. Benzophenone sensitization yields 16 (Φ =0.11) and 17 (Φ = 0.11). The dimethoxybarrelene 9 gives only semibullvalene 10 , this resulting from di-π-methane rearrangement involving the vinyl and vinyldiester bridges, upon direct (Φ = 0.009) or benzophenone sensitized irradiations (Φ = 0.38). 10 undergoes a vinylcyclopropane rearrangement to give semibullvalene 11 upon direct or acetone sensitized irradiations (Φ = 0.008). 相似文献
86.
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88.
G. Kalai Professor M. Maschler Professor G. Owen 《International Journal of Game Theory》1975,4(4):193-213
The foundation of a dynamic theory for the bargaining sets started withStearns, when he constructed transfer sequences which always converge to appropriate bargaining sets. A continuous analogue was developed byBillera, where sequences where replaced by solutions of systems of differential equations. In this paper we show that the nucleolus is locally asymptotically stable both with respect toStearns' sequences andBillera's solutions if and only if it is an isolated point of the appropriate bargaining set. No other point of the bargaining set can be locally asymptotically stable. Furthermore, it is always stable in these processes. As by-products of the study we derive the results ofBillera andStearns in a different fashion. We also show that along the non-trivial trajectories and sequences, the vector of the excesses of the payoffs, arranged in a non-increasing order, always decreases lexicographically, thus each bargaining set can be viewed as resulting from a certain monotone process operating on the payoff vectors. 相似文献
89.
90.
Microwave spectra of 1,3-dithiole-2-one show that the molecule has a planar equilibrium conformation. IR and Raman spectra are analysed to give the normal modes of vibration. 相似文献