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Adriano Montanaro 《Journal of Elasticity》1997,46(3):217-221
The proofs of the Fedorov–Stippes and Fedorov's theorems, which hold for linearly elastic homogeneous bodies in natural configurations, remain valid for any linearly elastic medium with initial stress provided that Hooke's tensor be replaced by a suitable elasticity tensor. 相似文献
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Adriano Montanaro 《Meccanica》1993,28(4):358-358
Uniqueness theorems for the entropy in any differential body of complexity one 相似文献
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Roberto Rossi Andrea Marchi Adriano Duatti Luciano Magon Plinio Di Bernardo 《Transition Metal Chemistry》1985,10(4):151-153
Summary The rhenium(V) imido-complexes [Re(NR)Cl3(PPh3)2] have been obtained by heating the rhenium(V) derivative [ReOCl3(PPh3)2] with RNHCHNR R = Ph (1a), p-MeC6H4 (1b), p-ClC6H4 (1c) andp-FC6H4 (1d) in THF under reflux. [Re(NR)Cl3(PPh3)2] (R =p-MeQ6H4) has also been obtained by heating the rhenium(III)-triazenido complex [ReCl2(RN
N
NR)(PPh3)2] in CCl4 under reflux. 相似文献
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Several π-excessive heteropolyaromatic compounds, which contain furan and thiophen ring and are possible antifungal agents, have been synthesized in good yields according to two general methods. The first method has been used to prepare compounds possessing thiophens linked by their 2- and 5-positions, such as the ter-aryls , and . Two precursors of these compounds have been obtained either by the Glaser reaction, or using a novel Pd-mediated reaction. The second method,which consists of the Ni-or Pd-catalyzed heteroarylation of heteroarene halides via cross-coupling with heteroaryl Grignard reagents or zinc halides,has been used to prepare the bi-aryls , which contain two heteroaromatic units, and the ter-aryl . Compound has been also prepared starting from 2-(2-thienyl) furan () by selective lithiation, followed by bromination.The 13C NMR signals of and have been assigned on the basis of the literature data and by relaxation measurements. Relaxation data have been also used to obtain qualitative informations on the conformational equilibria of the bi-aryls , and the ter-aryls . 相似文献
70.
Adriano B. Pangelinan R. L. McCullough Michael J. Kelley 《Journal of Polymer Science.Polymer Physics》1994,32(14):2383-2394
An analytic model based on a random-walk formulation for absorbing barriers is presented. The range of applicability of the model is established from results derived from Monte Carlo simulations. The model takes into account the influences of neutral, repulsive, and attractive polymer-surface interactions on the spatial variation of species concentrations in the vicinity of a surface. The model predicts that the lower molecular weight species of a polydisperse mixture will accumulate in the vicinity of a surface to create an interphase region. The extent of this surface-perturbed interphase region is on the order of three times the radius of gyration of the longest species of the mixture. The degree of molecular weight segregation is dependent upon the breadth of the molecular weight distribution. © 1994 John Wiley & Sons. Inc. 相似文献