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31.
Kay Gore 《School science and mathematics》1986,86(3):263-265
Computer Science II: File Structure Charged Particles II South Dakota: An Economic and Math Simulation 相似文献
32.
Fast (6250 Hz) line-of-sight measurements of infrared spectral radiation intensities (Iλ) from a luminous flame and a new deconvolution technique for the estimate of local scalar properties using inverse radiation calculations are reported. Time series data of Iλ for one diametric and nine chord-like radiation paths in a representative horizontal plane were measured. Statistical properties of Iλ, including mean, root mean square (rms), probability density function, autocorrelation coefficient, and power spectral density, were obtained from the time series data. The measured statistical properties of Iλ at two representative wavelengths, which are dominated by carbon dioxide (CO2) and soot radiation, respectively, are reported. The autocorrelation coefficient data show large negative loops with repeatable zero crossings at 20 ms and minimum values as low as −0.2 at 30–40 ms. Radial distributions of mean and rms CO2 mole fractions and temperatures were estimated using inverse calculations of mean Iλ at two different wavelengths dominated by CO2 radiation in conjunction with the relationship of these quantities to mixture fractions. Soot volume fraction distributions were also estimated using inverse calculations of mean Iλ at a wavelength dominated by continuum soot radiation. The estimated local mixture fraction distributions were in reasonably good agreement with sampling data from similar flames. The calculated mean Iλ from 1.4 to 4.8 μm other than those used in the inverse calculations matched the experimental data well. The present method provides non-intrusive measurements of major gas species and temperature statistics in turbulent soot containing flames not accessible to other optical diagnostics. 相似文献
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Sparham C van Egmond R Hastie C O'Connor S Gore D Chowdhury N 《Journal of chromatography. A》2011,1218(6):817-823
Robust analytical procedures for the measurement of decamethylcyclopentasiloxane (D5) in river and estuarine sediments and their application in determining environmental concentrations in the UK are presented for the first time in this work. Novel approaches to minimise commonly reported artefacts are utilised, improving the confidence in the concentrations of D5 reported. Accelerated solvent extraction (ASE) and liquid–solid extraction methods are compared. Both methods use on-column injection gas chromatography/mass spectrometry (GC/MS). Measurements of D5 concentrations in sediments sampled from the river Great Ouse and from the Humber estuary (UK) are also reported. ASE was suitable to measure concentrations of D5 in sediments obtained from the river Great Ouse, UK (186–1450 ng g−1, dry weight) and octamethyltetracyclosiloxane (D4, 12–24 ng g−1, dry weight). C12 linear alkybenzene (C12 LAB), which can be used as a chemical marker for sewage effluent related emissions, was also measured in this analysis. Liquid–solid extraction was optimised to provide more confidence in the lower D5 concentrations measured in the Humber estuary, UK (49–256 ng g−1, dry weight). A Limit of quantitation (LOQ) for D5 of 57–110 and 4 ng g−1 dry weight was determined for ASE and liquid–solid extraction, respectively. 相似文献
34.
P. Ravi G.M. Gore Surya P. Tewari A. K. Sikder 《International journal of quantum chemistry》2011,111(15):4352-4362
In this study, we explore the possibility that fused polynitrodiazoles act as high energy density materials. Density functional theory calculations at the B3LYP/aug‐cc‐pVDZ level were performed to predict the structure, energy of explosion (≈1.68 kcal g?1), density (≈1.98 g cm?3), detonation velocity (≈9.50 km s?1), and detonation pressure (≈41.50 GPa) of model molecules. The predicted properties have been found to be promising compared with 3,4,5‐trinitro‐1H‐pyrazole, 1,3,5‐trinitro‐1,3,5‐triazinane, and octahydro‐1,3,5,7‐tetranitro‐l,3,5,7‐tetraazocane. The nature of azoles of the molecule presumably determines the geometry, stability, sensitivity, density, and detonation performance. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 相似文献
35.
E. F. Jones P. M. Gore S. J. Zhu J. H. Hamilton A. V. Ramayya J. K. Hwang R. Q. Xu L. M. Yang K. Li Z. Jiang Z. Zhang S. D. Xiao X. Q. Zhang W. C. Ma J. D. Cole M. W. Drigert I. Y. Lee J. O. Rasmussen Y. X. Luo M. A. Stoyer 《Physics of Atomic Nuclei》2006,69(7):1198-1203
We have used our analysis of γ-γ-γ data (5.7 × 1011 triples and higher folds) taken with Gammasphere from prompt γ rays emitted in the spontaneous fission of 252Cf to study the collective bands in 104,106,108Mo. The one-phonon and two-phonon γ-vibrational bands and known two-quasiparticle bands in neutron-rich 104,106Mo were extended to higher spins. The one-and two-phonon γ-vibrational bands have remarkably close energies for transitions from the same spin states and identical moments of inertia.
Several new bands are observed and are proposed as quasiparticle bands in 104,106Mo, along with the first β-type vibrational band in 106Mo. The quasiparticle bands have essentially constant moments of inertia near the rigid-body value that indicate blocking
of the pairing interaction. Candidates for chiral doublet bands in 106Mo are strong. These are the first reported chiral vibrational bands in an even-even nucleus.
The text was submitted by the authors in English. 相似文献
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Regio and stereoselectivity of the palladium catalyzed reduction of propargylic halides and esters is greatly influenced by the nature of the hydride donor as by the leaving group. Best results in allene formation are observed in the reduction by lithium triethyl-borohydride of mesylates and phosphates. In the former case, reaction occurs with anti displacement of the sulfonyl group. 相似文献
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Tertiary 1,5-hexadien-3-ols are transformed to δ-ethylene ketones in 35–75 % yield by treatment with one equivalent of mercuric trifluoroacetate and subsequent demercuration using sodium borohydride (Scheme 1, Table). 相似文献