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MARCEL SNELS HANS HOLLENSTEIN MARTIN QUACK ELISABETTA CANÉ ANDREA MIANI AGOSTINO TROMBETTI 《Molecular physics》2013,111(7):981-1001
We report results from measurements of the high resolution FTIR spectrum for the fully deuterated benzene molecule C6D6 in the range 450–3500 cm?1. Accurate spectroscopic constants have been obtained for the fundamental vibration ν11 at 496.208 cm?1 and improved ground state constants have been deduced from a fit of ground state combination differences. The J structure of the combination parallel bands ν2 + ν11 (at 2798.1 cm?1), ν5 + ν12 (1802.5 cm?1) and ν7, + ν16 (2619.3 cm?1) of C6D6 has been analysed as well, from which improved values of the band origin and of the B and D j constants of the excited states have been obtained. The strongest hot bands accompanying these parallel transitions have been assigned by means of the anharmonic force field calculated by Maslen et al. [1992, J. chem. Phys., 97, 4233]. In particular (ν11 + ν16) ? ν16 is assigned to the band at 492.4 cm?1 even though its shape is typical of a perpendicular transition (PAPE). New values for the ν5, ν12 and ν16 band origins are determined from the band origins of combination bands and from calculated anharmonic constants. Numerous anharmonic constants are derived from the assignment of hot band and combination transitions. 相似文献
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Evidence, amongst Triassic thecodonts, of energetic upright postures and advanced bipedalism (or the vestiges of such characteristics) reveals that both endothermic and ectothermic thecodonts were descended from warm-blooded archosaurs with rapid metabolisms. Arboreal and aquatic adaptations in bipedal iguanians, and in extinct thecodonts, suggest that the emergence of reptilian bipedal locomotion is related to an arboreal-aquatic existence. But endothermy-required obligatory bipedalism could not have arisen in fauna-poor freshwater environments. The possible existence, in faunivorous thecodonts, of functional (or vestigial) cranial salt glands may suggest that the earliest semiaquatic archosaurs originated in fauna-prolific marine environments. If archosaurs were originally semiaquatic (marine) predators, then the existence of archosaurian endothermy could have initially emerged as an adaptation to increase metabolic heat production under the enhanced thermal cold stresses of the marine hydrosphere, while concurrently augmenting the rate of metabolic water production within saltwater environments inherently lacking in palatable freshwater resources. 相似文献
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The $t\bar{t}+\mbox{1-jet} + X$ differential cross-section in proton?Cproton collisions at 7?TeV centre of mass energy is investigated with respect to its sensitivity to the top quark mass. The analysis includes higher order QCD corrections at NLO. The impact of the renormalization scale (?? R), the factorization (?? F) scale and of the choice of different proton??s PDF (parton distribution function) has been evaluated. In this study it is concluded that differential jet rates offer a promising option for alternative mass measurements of the top quark, with theoretical uncertainties below 1 GeV. 相似文献
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MARCEL VAN ASSEN CHRIS SNIJDERS JEROEN WEESIE 《The Journal of mathematical sociology》2013,37(2):159-180
A fuzzy set theoretical framework is proposed for the analysis of sociometric structure characterized by vagueness of liking between individuals and a person's relative degree of belonging to a social group. Max‐min transitivity of a fuzzy relation is employed as a basic concept to examine the degree of liking and clustering in group structures. A distance model based on min‐max transitivity is also formulated as a special case of transitivity analysis. Other notions of transitivity such as the max‐product and the max‐* are also discussed. An empirical analysis is performed to examine the applicability of the proposed transitivity concepts. It appears that the current methodological construct provides a more appropriate perspective in the analysis of the group structure properties. 相似文献
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MARCEL AILLERY NOEL GOLLEHON VINCE BRENEMAN SHAWN BUCHOLTZ 《Natural Resource Modeling》2009,22(1):42-66
Abstract A regional modeling framework using national data series is developed to estimate the net cost of land‐applying manure under possible policy provisions to limit water‐ and air‐quality emissions. The modeling framework, applied to the Chesapeake Bay watershed, integrates GIS‐based spatial data within an optimization model to capture spatial effects at a subwatershed scale. 相似文献
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We consider the universal central extension of the Lie algebra Vect(S
1) C(S
1). The coadjoint representation of thisLie algebra has a natural geometric interpretation by matrix analogues ofthe Sturm –Liouville operators. This approach leads to new Liesuperalgebras generalizing the well-known Neveu –Schwarz algebra. 相似文献
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