2 resultados para anthropogenic pressures

em Bucknell University Digital Commons - Pensilvania - USA


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The Gaussian-2, Gaussian-3, complete basis set- (CBS-) QB3, and CBS-APNO methods have been used to calculate ΔH° and ΔG° values for neutral clusters of water, (H2O)n, where n = 2−6. The structures are similar to those determined from experiment and from previous high-level calculations. The thermodynamic calculations by the G2, G3, and CBS-APNO methods compare well against the estimated MP2(CBS) limit. The cyclic pentamer and hexamer structures release the most heat per hydrogen bond formed of any of the clusters. While the cage and prism forms of the hexamer are the lowest energy structures at very low temperatures, as temperature is increased the cyclic structure is favored. The free energies of cluster formation at different temperatures reveal interesting insights, the most striking being that the cyclic trimer, cyclic tetramer, and cyclic pentamer, like the dimer, should be detectable in the lower troposphere. We predict water dimer concentrations of 9 × 1014 molecules/cm3, water trimer concentrations of 2.6 × 1012 molecules/cm3, tetramer concentrations of approximately 5.8 × 1011 molecules/cm3, and pentamer concentrations of approximately 3.5 × 1010 molecules/cm3 in saturated air at 298 K. These results have important implications for understanding the gas-phase chemistry of the lower troposphere.

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Interpretations of Shakespeare’s characters have been subject to the pressures of history, exhibiting a progression of performance styles in accordance with changes in ideas and concerns over time. Shakespeare’s complex portrayals of women leave room for cultural influences of a time period to greatly influence interpretations because of the ambiguous nature of some of his major female characters. Lady Macbeth and Much Ado About Nothing’s Beatrice both overstep and challenge gender boundaries, and the combination of their defiant natures and textual ambiguities have made these characters highly controversial over the past four centuries.Various cultures over time have imposed specific readings of the characters that serve to reinforce the male-dominated expectations of a given society. The examination of variations in performance styles and interpretations of these two extremely canonical characters revealinsights into gender ideologies that existed during various time periods throughout history. The combination of this analysis with an exploration of the effects of the more recent applications offeminism and film, which have both helped to reshape the cultural images of both Lady Macbeth and Beatrice, will aide in an observation of the status of gender relations in our contemporary society. The current trend of interpretations of these characters could also provide predictions about future gender relations in our culture.