1000 resultados para Ab


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A fluorescence excitation spectrum of formic acid monomer (HCOOH) , has been recorded in the 278-246 nm region and has been attributed to an n >7r* electron promotion in the anti conformer. The S^< S^ electronic origins of the HCOOH/HCOOD/DCOOH/DCOOD isotopomers were assigned to weak bands observed at 37431.5/37461.5/37445.5/37479.3 cm'''. From a band contour analysis of the 0°^ band of HCOOH, the rotational constants for the excited state were estimated: A'=1.8619, B'=0.4073, and C'=0.3730 cm'\ Four vibrational modes, 1/3(0=0), j/^(0-C=0) , J/g(C-H^^^) and i/,(0-H^yJ were observed in the spectrum. The activity of the antisymmetric aldehyde wagging and hydroxyl torsional modes in forming progressions is central to the analysis, leading to the conclusion that the two hydrogens are distorted from the molecular plane, 0-C=0, in the upper S. state. Ab initio calculations were performed at the 6-3 IG* SCF level using the Gaussian 86 system of programs to aid in the vibrational assignments. The computations show that the potential surface which describes the low frequency OH torsion (twisting motion) and the CH wagging (molecular inversion) motions is complex in the S^ excited electronic state. The OH and CH bonds were calculated to be twisted with respect to the 0-C=0 molecular frame by 63.66 and 4 5.76 degrees, respectively. The calculations predicted the existence of the second (syn) rotamer which is 338 cm'^ above the equilibrium configuration with OH and CH angles displaced from the plane by 47.91 and 41.32 degrees.

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A black and white photograph of Lizzie Sloman, with two men identified on the reverse as Ab (left) and son (right). The photograph is not dated but is recorded as being taken in London, Ontario. It appears the photo marks some occasion, as one gentleman is in full uniform, while the other is wearing a corsage. This photograph was in the possession of Rick Bell, of St. Catharines, whose mother was born a Sloman.

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Brown sediment with clasts ranging from small to large in size. Clast shape ranges from sub-angular to sub-rounded. The clasts are generally well dispersed, with a few areas of closer aggregates. Lineations are common throughout the sample. A few rotation structures and a few areas of edge-to-edge grain crushing can also be seen. Comet structures can also be seen in very minor amounts.

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Brown sediment with clasts ranging from small to medium in size. Grain shape ranges from angular to sub-rounded. Water escape structures and lineations are abundant throughout the sample. Some comet structures can also be seen. There were minor amounts of grain crushing also present.

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Appendix seu altera collectio quamplurimorum summariorum indulgentiarum... (243 p.)