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91.
The accumulation of plastic strain over a number of cycles of heating and cooling of the outer surface of a loaded thick-walled circular cylinder is computed. Two types of loadings are considered, viz. pure axial torsion and a combination of torsion and tension. The cylinder material is taken to be isotropic and linear strain-hardening; its yield stress reduces with temperature and with the number of thermal cycles completed. This cyclic softening is shown to produce an incremental collapse or ratcheting behaviour in contrast to the alternating plasticity which occurs when the yield stress on first loading is maintained. 相似文献
92.
Summary Let Lεu and L
0
v be the elliptic and “backward” heat operators defined by(1.1) and(1.2), respectively. The following question is considered for a pair of “non-well posed” initial-boundary value problems for Lε and L
0
: if u and v are the respective solutions, under what restrictions on the classes of admissible solutions and in what sense,
if any, does u converge to v as ɛ →0?
This research was supported in part by the National Science Foundation Grant No. GP 5882 with Cornell University. 相似文献
93.
In this note we prove strong superadditivity properties of the stress function in the elastic torsion problem for multiply connected regions. The results are extended to associated Green's functions and other domain functions. 相似文献
94.
95.
The rate constant for the reaction of Br + O3 → BrO + O2 has been measured at four temperatures from 234 to 360 K by the technique of discharge flow coupled with resonance-fluorescence detection of bromine atoms. The measured rate constants obey the Arrhenius expression k = (9.45 ± 2.48) × 10?12 exp(-659 ± 64/T) cm3/molec·sec (one standard deviation). The results are compared with two previous studies, one of which utilized the flash-photolysis–resonance-fluorescence technique and the other utilized the discharge-flow–mass-spectrometric technique. The result is also discussed from a theoretical point of view. 相似文献
96.
Summary Bentonite and stockalite clay-water systems were strained sinusoidally in shear over a wide strain range. The hysteresis loops were shown to vary from an almost straight line (elastic system) to a ferromagnetic type loop (plastic system) as the energy of oscillation was increased. The normalised dynamic modulus-strainwork plots were shown to be very similar to those observed in carbon black-elastomer and carbon black-paraffin systems.
Paper presented at the British Society of Rheology Conference. held at Shrivenham, from 9th–12th September, 1968. 相似文献
Zusammenfassung Über einen weiten Dehnbereich werden Bentonit- und Stockalit-Wasser-Systeme einer sinusförmigen Dehnbeanspruchung ausgesetzt. Die Hystereseschleifen variieren mit wachsender Schwingungsenergie von einer geraden Linie (elastisches System) bis zu einer Art ferromagnetischer Schleife (plastisches System). Die normierten dynamischen Modul-Dehnungsarbeit-Diagramme sind bei den Ruß-Elastomer- und Ruß-Paraffin-System beobachteten sehr ähnlich.
Paper presented at the British Society of Rheology Conference. held at Shrivenham, from 9th–12th September, 1968. 相似文献
97.
98.
J. L. Friar B. F. Gibson G. L. Payne 《Zeitschrift für Physik A Hadrons and Nuclei》1983,312(3):169-175
The triton ground-state wave function calculated using the Reid soft-core potential is displayed in configuration space. Both the S-state and D-state Schrödinger wave function components and the Faddeev amplitudes from which they are constructed are plotted. Specific features resulting from the tensor nature of the two-body force and from the strong short-range repulsion of the potential are discussed. Comparisons with corresponding functions generated by the Malfliet-Tjon s-wave potential model are made. Several intuitive features of the Schrödinger wave function are discussed. 相似文献
99.
Natalia Zaitseva Leslie Carman Andrew Glenn Jason Newby Michelle Faust Sebastien Hamel Nerine Cherepy Stephen Payne 《Journal of Crystal Growth》2011,314(1):163-170
Single crystals of a pure hydrocarbon, 1,3,5-triphenylbenzene, with properties suitable for high-energy neutron detection were grown from toluene solutions using slow evaporation and temperature reduction methods with growth rates up to 10 mm/day. Application of the rapid growth technique developed earlier for growth of large water-soluble crystals shows that crystals of aromatic compounds can be successfully grown from solutions in large volumes required for their use as scintillator materials for radiation detection. 相似文献
100.
Sam Payne 《Mathematische Zeitschrift》2006,253(2):421-431
We show that the dual of the cone of divisors on a complete -factorial toric variety X whose stable base loci have dimension less than k is generated by curves on small modifications of X that move in families sweeping out the birational transforms of k-dimensional subvarieties of X. We give an example showing that it does not suffice to consider curves on X itself.
Supported by a Graduate Research Fellowship from the NSF 相似文献