11,248 research outputs found

    Monthly mean global satellite data sets available in CCM history tape format

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    Satellite data for climate monitoring have become increasingly important over the past decade, especially with increasing concern for inadvertent antropogenic climate change. Although most satellite based data are of short record, satellites can provide the global coverage that traditional meteorological observations network lack. In addition, satellite data are invaluable for the validation of climate models, and they are useful for many diagnostic studies. Herein, several satellite data sets were processed and transposed into 'history tape' format for use with the Community Climate Model (CCM) modular processor. Only a few of the most widely used and best documented data sets were selected at this point, although future work will expand the number of data sets examined as well as update the archived data sets. An attempt was made to include data of longer record and only monthly averaged data were processed. For studies using satellite data over an extended period, it is important to recognize the impact of changes in instrumentation, drift in instrument calibration, errors introduced by retrieval algorithms and other sources of errors such as those resulting from insufficient space and/or time sampling

    A computer program to calculate radiating viscous stagnation streamline flow with strong blowing

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    A computer program (program LEE) has been developed to calculate the fully coupled solution of the radiating viscous stagnation streamline flow with strong blowing. The report describes the digital computer program, including FORTRAN IV listing, flow charts, instructions for the user, and a test case with input and output. Program LEE is available through COSMIC

    Characterization and Dynamics of Substituted Ruthenacyclobutanes Relevant to the Olefin Cross-Metathesis Reaction

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    The reaction of the phosphonium alkylidene [(H_(2)IMes)RuCl2ā•CHP(Cy)_3)]^(+) BF_(4)^āˆ’ with propene, 1-butene, and 1-hexene at āˆ’45 Ā°C affords various substituted, metathesis-active ruthenacycles. These metallacycles were found to equilibrate over extended reaction times in response to decreases in ethylene concentrations, which favored increased populations of Ī±-monosubstituted and Ī±,Ī±ā€²-disubstituted (both cis and trans) ruthenacycles. On an NMR time scale, rapid chemical exchange was found to preferentially occur between the Ī²-hydrogens of the cis and trans stereoisomers prior to olefin exchange. Exchange on an NMR time scale was also observed between the Ī±- and Ī²-methylene groups of the monosubstituted ruthenacycle (H_(2)IMes)Cl_(2)Ru(CHRCH_(2)CH_(2)) (R = CH_3, CH_(2)CH_3, (CH_2)_)_(3)CH_3). EXSY NMR experiments at āˆ’87 Ā°C were used to determine the activation energies for both of these exchange processes. In addition, new methods have been developed for the direct preparation of metathesis-active ruthenacyclobutanes via the protonolysis of dichloro(1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene)(benzylidene) bis(pyridine)ruthenium(II) and its 3-bromopyridine analogue. Using either trifluoroacetic acid or silica-bound toluenesulfonic acid as the proton source, the ethylene-derived ruthenacyclobutane (H_(2)IMes)Cl_(2)Ru(CH_(2)CH_(2)CH_(2)) was observed in up to 98% yield via NMR at āˆ’40 Ā°C. On the basis of these studies, mechanisms accounting for the positional and stereochemical exchange within ruthenacyclobutanes are proposed, as well as the implications of these dynamics toward olefin metathesis catalyst and reaction design are described

    Test of variational transition state theory against accurate quantal results for a reaction with very large reaction-path curvature and a low barrier

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    We present three sets of calculations for the thermal rate constants of the collinear reaction I+HI-->IH+I: accurate quantum mechanics, conventional transition state theory (TST), and variational transition state theory (VTST). This reaction differs from previous test cases in that it has very large reaction-path curvature but hardly any tunneling. TST overestimates the accurate results by factors of 2Ɨ10^10, 2Ɨ10^4, 57, and 19 at 40, 100, 300, and 1000 K, respectively. At these same four temperatures the ratios of the VTST results to the accurate quantal ones are 0.3, 0.8, 1.1, and 1.4, respectively. We conclude that the variational transition states are meaningful, even though they are computed from a reaction-path Hamiltonian with large curvature, which is the most questionable case

    Socioeconomic impact of photovoltaic power at Schuchuli, Arizona

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    The social and economic impact of photovoltaic power on a small, remote native American village is studied. Village history, group life, energy use in general, and the use of photovoltaic-powered appliances are discussed. No significant impacts due to the photovoltaic power system were observed

    Broad applications of diffusion bonding

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    Solid state joining of materials by diffusion bondin

    False Presumptions Counter to the Presumptions of Innocence

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    Function of Punishment

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