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111.
David S. Wragg Benjamin Le Ouay Matthew G. O’Brien John E. Warren Russell E. Morris 《Journal of solid state chemistry》2010,183(7):1625-3071
We have prepared isostructural aluminium and gallium phosphate chains by ionothermal reactions in 1-ethyl-3-methylimidazolium bromide and 1-ethylpyridinium bromide under a variety of conditions. The chains can be prepared as pure phases or along with three dimensional framework phases. The chains are favoured at shorter heating times and the crystallinity can be improved by addition of transition metal acetates and amines which are not included in the final structure. The chain can be prepared with or without the presence of hydrofluoric acid. 相似文献
112.
113.
<Emphasis Type="Italic">L</Emphasis><Superscript>2</Superscript>-Betti numbers of one-relator groups
We determine the L
2-Betti numbers of all one-relator groups and all surface-plus-one-relation groups. We also obtain some information about the
L
2-cohomology of left-orderable groups, and deduce the non-L
2 result that, in any left-orderable group of homological dimension one, all two-generator subgroups are free.
Warren Dicks was Funded by the DGI (Spain) through Project BFM2003-06613. 相似文献
114.
115.
A direct synthesis of trimethyl(2-phenoxyethyl)silanes from the corresponding aromatic fluorides and 2-(trimethylsilyl)ethanol was developed. A variety of substituents were tolerated and a substitution reaction using 1-bromo-3-chloro-5-fluorobenzene was demonstrated. 相似文献
116.
117.
To study digital Mott insulator LaTiO3 and band insulator SrTiO3 interfaces, we apply correlated band theory within the local density approximation including a Hubbard U to (n, m) multilayers, 1相似文献
118.
George E. Warren 《Experimental Mechanics》1975,15(5):201-208
This paper presents the three-dimensional photoelastic analyses accompanied by extensive finite-element studies of several thin-shell pressure vessels with various cylindrical intersections. The models consisted of right circular cylindrical shells with diameter-to-thickness ratios of 220, reinforced with circumferential, longitudinal and diagonal T-stiffeners. The cylindrical shells and stiffeners were intersected by various smaller cylinders producing complex intersection joints which included radial and angular fillets. Each of the models was constructed from 80 to 150 parts prepared from flat sheets, “contour-cast” shells, and milled machined parts. The model techniques as well as the machining, assembling and testing methods of the pressure vessels are presented. 相似文献
119.
Three test series of single-edge-notched beams in three-point bending are conducted to evaluate the fracture energy of concrete.
The fracture energy is determined from the area under the complete load: load-point deflection diagram. The nonlinear fictitious
crack model is implemented in a finite-element analysis showing good agreement with the experimental data.
By varying the notch depth and the beam depth it is shown that the fracture energy, traditionally presented as a material
property, depends upon the specimen size and configuration. This is atributed to the energy dissipation in the process zone
which is not accounted for in the analytical model. 相似文献
120.
Warren C. Young 《Experimental Mechanics》1969,9(6):275-280
The use of two monochromatic light sources to obtain two isochromatic patterns permits a fully automated shear-difference analysis of the stress distribution in a three-dimensional photoelastic model. A development is given of the logic necessary to process the data taken from an automated polariscope as well as the design details of the polariscope. 相似文献