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991.
Michael P. Ebdon O. Delatycki John G. Williams 《Journal of Polymer Science.Polymer Physics》1974,12(8):1555-1564
Composite specimens were prepared using soda glass beads and a purified epoxy resin cured with 1,3-propylene diamine. Some beads were treated with a silane coupling agent. The dynamic mechanical properties of these specimens were measured in the temperature range ?190 to +180°C using a free-oscillation torsion pendulum. The dynamic mechanical relaxation spectrum showed no feature that could be attributed to the formation of a new interfacial phase and the torsional moduli were unaffected by the use of the coupling agent. Increasing the glass content of the specimens decreased the damping and increased the modulus. An attempt was made to predict the composite modulus using the Kerner equation. When the specimens were immersed in boiling water, two effects were noted. First, water was absorbed in the epoxy resin matrix and changes in the dynamic spectrum were observed. Second, in samples filled with untreated glass debonding occurred and the presence of free water at the interface was indicated by the appearance of a new peak near 0°C. 相似文献
992.
993.
High resolution two-dimensional electrophoresis indicates that serum proteins previously only detected in patients with acute myocardial infarction (AMI) (Gomo et al., Electrophoresis 1983, 4, 298-302) are also present in the serum protein patterns of other patients (AMI negative or demonstrating acute phase response) and are faintly detected even in controls. Thus, these proteins are not specific to AMI and are probably acute phase reactants. However, they do demonstrate a characteristic time course response in sequential samples from AMI patients. 相似文献
994.
995.
2 The2′-bisacylazide of 3,3′-bipyridine (1) has been synthesized from the (4,7)-phenantholine-5,6-dione ( 3 ) and the thermal decomposition of this new bisacylazide has been shown to give rise to the Curtius rearrangement and subsequent cyclization to the pyrido[2,3-h]-2,6-naph-thridinone ring system 8 . 相似文献
996.
V. Cook G. Hicks P.M. Mockett J.E. Rothberg R.W. Williams K.K. Young P. Limon P. Mantsch J.R. Orr S. Pruss W.P. Oliver 《Nuclear Physics B》1981,186(2):219-235
Large aperture calorimeter measurements of high transverse momentum events from 100, 200 and 340 GeV pp collisions are reported. Yields are higher by one to two orders of magnitude than the yield expected from uncorrelated statistical fluctuations in multiparticle events. The exponential slopes of the yields versus xt exhibited a systematic change with . The events are shown to be more diffuse than pure jets as produced in e+e? collisions. However, these events are consistent with a QCD-inspired 4-jet model. 相似文献
997.
A.C. Lawson A. Williams J.L. Smith P.A. Seeger J.A. Goldstone J.A. ORourke Z. Fisk 《Journal of magnetism and magnetic materials》1985,50(1):83-87
The magnetic ordering of the intermetallic compounds UGa3 and UGa2 has been examined by time-of-flight neutron diffraction, and the nature of the magnetic order of these compounds is confirmed. 相似文献
998.
Roger Bolton W.K. Adrian Moss John P.B. Sandall Gareth H. Williams 《Journal of fluorine chemistry》1975,5(1):61-65
The thermolyses of a number of aroyl peroxides in hexafluorobenzene, and of benzoyl peroxide in octafluorotoluene, gave the corresponding biaryls which were isolated by steam distillation. Mass spectrometry of the residues showed evidence of biphenylyl radicals arising from the arylation of the peroxides themselves or, possibly, of the derived aroic acids. Terphenyls, and the corresponding σ-intermediate radicals, could be found, and the relative molecular masses of the latter components showed that subsequent arylation of the main binuclear products was not the main source of terphenyls. 相似文献
999.
1000.