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101.
A model for lubricated squeezing flow of a viscoelastic fluid is developed in order to study the viability of this flow as
a rheological technique for generating equibiaxial extensional deformations in polymer melts. In this simple flow model, the
melt, described by an upper-convected Maxwell fluid, is squeezed between thin films of a Newtonian fluid. Comparisons of the
model predictions for constant strain rate and constant stress flows are made with experimental results presented in the first
paper. Predictions from the model are able to describe the effects of lubricant viscosity and experimental configuration and
indicate the technique fails for these flows at Hencky strains of approximately one. The cause for this failure is lubricant
thinning, which leads to significant errors in both the measured stress difference and the strain.
Received: 31 January 2000 Accepted: 31 May 2000 相似文献
102.
103.
104.
E.F. Moore M.P. Carpenter R.V.F. Janssens T.L. Khoo T. Lauritsen D. Ackermann I. Ahmad H. Amro D. Blumenthal S. Fischer G. Hackman D. Nisius F. Hannachi A. Lopez-Martens S. J. Asztalos R.M. Clark M.A. Deleplanque R.M. Diamond P. Fallon R. Krueken I-Y. Lee A.O. Macchiavelli F.S. Stephens J.A. Becker L. Bernstein L.P. Farris E.A. Henry A. Korichi 《Zeitschrift für Physik A Hadrons and Nuclei》1997,358(2):219-223
The lifetimes of states in Superdeformed (SD) bands in 192,194Hg have been measured using the Doppler shift attenuation method. Intrinsic quadrupole moments have been extracted for band 1 of 192Hg and for bands 1, 2, and 3 of 194Hg. It was found that the quadrupole moments for the “identical” SD bands in these nuclei are the same. In the same experiment, one-step transitions linking SD states to yrast and near yrast states for bands 1 and 3 of 194Hg have been identified. From this observation, excitation energies, spins and probable parities have been assigned to SD states in these bands. 相似文献
105.
We characterize the range of the cosine transform on real Grassmannians in terms of the decomposition under the action of the special orthogonal group SO(n). We also give a geometric interpretation of this image in terms of valuations. In addition, we discuss the non-Archimedean analogues. 相似文献
106.
D.R. Symes J. Osterhoff R. Fustlin M. Maurer A.C. Bernstein A.S. Moore E.T. Gumbrell A.D. Edens R.A. Smith T. Ditmire 《High Energy Density Physics》2007,3(3-4):353-357
To study hydrodynamic behavior on thin shell high Mach number blast waves, experiments have been performed in which spatially tailored shock waves have been launched in a gas of clusters using an intense 35 fs laser pulse. The target medium was first modified by destroying clusters in specific locations using a spatially modulated laser focus. Under subsequent intense laser irradiation, the efficient absorption properties of the remaining clustered regions compared to those regions with no clusters led to a pattern of hot and cold plasma resulting in a cylindrical blast wave with a periodic modulation imprinted on the shock front. This technique may provide a method for studying thin shell instabilities in strongly radiative blast waves. 相似文献
107.
Kyungwha Park Mark R Pederson Noam Bernstein 《Journal of Physics and Chemistry of Solids》2004,65(4):805-811
A new type of the single-molecule magnet [Mn4O3Cl4(O2CEt)3(py)3] forms dimers. Recent magnetic hysteresis measurements on this single-molecular magnet revealed interesting phenomena: an absence of quantum tunneling at zero magnetic field and tunneling before magnetic field reversal. This is attributed to a significant antiferromagnetic exchange interaction between different monomers. To investigate this system, we calculate the electronic structure, magnetic properties, intramolecular and intermolecular exchange interactions using density-functional theory within the generalized-gradient approximation. Our calculations agree with experiment. We find that the calculated threefold symmetric structure is vibrationally stable. We also calculate vibrational infrared absorption and Raman scattering intensities for the monomer which can be tested experimentally. 相似文献
108.
109.
A. O. Bazarko C. G. Arroyo K. T. Bachmann T. Bolton C. Foudas B. J. King W. C. Lefmann W. C. Leung S. R. Mishra E. Oltman P. Z. Quintas S. A. Rabinowitz F. J. Sciulli W. G. Seligman M. H. Shaevitz F. S. Merritt M. J. Oreglia B. A. Schumm R. H. Bernstein F. Borcherding H. E. Fisk M. J. Lamm W. Marsh K. W. B. Merritt H. M. Schellman D. D. Yovanovitch A. Bodek H. S. Budd P. de Barbaro W. K. Sakumoto T. Kinnel P. H. Sandler W. H. Smith 《Zeitschrift fur Physik C Particles and Fields》1995,65(2):189-198
We present the first next-to-leading-order QCD analysis of neutrino charm production, using a sample of 6090
– and
-induced opposite-sign dimuon events observed in the CCFR detector at the Fermilab Tevatron. We find that the nucleon strange quark content is suppressed with respect to the non-strange sea quarks by a factor =0.477
–0.053
+0.063
, where the error includes statistical, systematic and QCD scale uncertainties. In contrast to previous leading order analyses, we find that the strange seax-dependence is similar to that of the non-strange sea, and that the measured charm quark mass,m
c
=1.70±0.19 GeV/c2, is larger and consistent with that determined in other processes. Further analysis finds that the difference inx-distributions betweenxs(x) and
is small. A measurement of the Cabibbo-Kobayashi-Maskawa matrix element |V
cd
|=0.232
–0.020
+0.018
is also presented. 相似文献
110.
Two-photon photoconductivity in ZnSe is used to record femtosecond autocorrelation functions. This technique requires <100 muW of average power of a typical mode-locked femtosecond Ti:sapphire laser and distinguishes itself by a dynamic range over several decades and great conversion bandwidth, permitting the sensitive correlation of pulses of a few femtoseconds. 相似文献