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111.
Julian D. Cole 《Theoretical and Computational Fluid Dynamics》1998,10(1-4):91-104
The hodograph method is used to formulate several design problems in transonic flow using small-disturbance theory. Analytical
and numerical methods give solutions to several optimum critical airfoil designs with different constraints on the tail angle.
Special airfoil shapes flying at free-stream Mach number one are designed. The problem of constructing a shock-free body of
revolution at subsonic speed but having a supersonic zone is formulated in the hodograph and solved numerically.
Received 10 January 1997 and accepted 14 April 1997 相似文献
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We previously described a high-accuracy version of the Yee algorithm that uses second-order nonstandard finite differences (NSFDs) and demonstrated its accuracy numerically. We now prove that at fixed frequency and grid spacing h, the leading error term is O(h/sup 6/) versus O(h/sup 2/) for the ordinary Yee algorithm with standard finite differences (SFDs). We numerically verify the superior accuracy of the NSFD algorithm by simulating near-field Mie scattering on a coarse grid and comparing with the SFD one and with analytical solutions. We present an updated stability analysis and show that the maximum time step for the NSFD algorithm is 20% longer than the SFD time step in two dimensions, and 36% longer in three dimensions. Finally, parameters that were previously given numerically are now analytically defined. 相似文献
115.
R. Aryaeinejad E. L. Reber J. K. Jewell J. D. Cole M. W. Drigert 《Journal of Radioanalytical and Nuclear Chemistry》2005,264(1):155-162
Summary In this work, prompt gamma-rays emitted by thermal neutron-induced fission decay using fast coincidence techniques are used to identify both light and heavy fragments and obtain gamma-ray signatures and radiation multiplicity. The measurements were carried out with 235U and 239Pu targets using the Intense Pulsed Neutron Source (IPNS) at Argonne National Laboratory. This study reports the recent results of a preliminary analysis of experimental data collected from the induced fission of 235U and 239Pu. In this paper, we discuss how these results could be used to characterize an unknown sample of fissile material. 相似文献
116.
Whitham modulation equations are derived for the nonlinear Schrödinger equation in the plane ((2+1)-dimensional nonlinear Schrödinger [2d NLS]) with small dispersion. The modulation equations are obtained in terms of both physical and Riemann-type variables; the latter yields equations of hydrodynamic type. The complete 2d NLS Whitham system consists of six dynamical equations in evolutionary form and two constraints. As an application, we determine the linear stability of one-dimensional traveling waves. In both the elliptic and hyperbolic cases, the traveling waves are found to be unstable. This result is consistent with previous investigations of stability by other methods and is supported by direct numerical calculations. 相似文献
117.
[Mg(Form)2(THF)] [Form = bis(2,6‐dimethylphenyl)formamidinate (XylForm) ( 1 ), bis(2,6‐diethylphenyl)formamidinate, (EtForm) ( 2 ), bis(2,6‐diisopropylphenyl)formamidinate (DippForm) ( 3 )] are conveniently synthesized by treating bis(2,6‐dimethylphenyl)formamidine, bis(2,6‐diethylphenyl)formamidine, or bis(2,6‐diisopropylphenyl)formamidine, respectively, with half an equivalent of dibutylmagnesium in THF. Compounds 1 – 3 are mononuclear species in the solid state with five coordinate central metal atoms. The 1H NMR chemical shift of the formamidinate formyl proton exhibits a correlation with ligand sterics wherein increasing bulk leads to a shift to higher field. 相似文献
118.
Biofunctionalization of Polyoxometalates with DNA Primers,Their Use in the Polymerase Chain Reaction (PCR) and Electrochemical Detection of PCR Products 下载免费PDF全文
Dr. Ahmed M. Debela Dr. Mayreli Ortiz Dr. Valerio Beni Prof. Serge Thorimbert Dr. Denis Lesage Prof. Richard B. Cole Prof. Ciara K. O'Sullivan Prof. Bernold Hasenknopf 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(49):17721-17727
The bioconjugation of polyoxometalates (POMs), which are inorganic metal oxido clusters, to DNA strands to obtain functional labeled DNA primers and their potential use in electrochemical detection have been investigated. Activated monooxoacylated polyoxotungstates [SiW11O39{Sn(CH2)2CO}]8? and [P2W17O61{Sn(CH2)2CO}]6? have been used to link to a 5′‐NH2 terminated 21‐mer DNA forward primer through amide coupling. The functionalized primer was characterized by using a battery of techniques, including electrophoresis, mass spectrometry, as well as IR and Raman spectroscopy. The functionality of the POM‐labeled primers was demonstrated through hybridization with a surface‐immobilized probe. Finally, the labeled primers were successfully used in the polymerase chain reaction (PCR) and the PCR products were characterized by using electrophoresis. 相似文献
119.
Kumar N Kent PR Bandura AV Kubicki JD Wesolowski DJ Cole DR Sofo JO 《The Journal of chemical physics》2011,134(4):044706
Proton jump processes in the hydration layer on the iso-structural TiO(2) rutile (110) and SnO(2) cassiterite (110) surfaces were studied with density functional theory molecular dynamics. We find that the proton jump rate is more than three times faster on cassiterite compared with rutile. A local analysis based on the correlation between the stretching band of the O-H vibrations and the strength of H-bonds indicates that the faster proton jump activity on cassiterite is produced by a stronger H-bond formation between the surface and the hydration layer above the surface. The origin of the increased H-bond strength on cassiterite is a combined effect of stronger covalent bonding and stronger electrostatic interactions due to differences of its electronic structure. The bridging oxygens form the strongest H-bonds between the surface and the hydration layer. This higher proton jump rate is likely to affect reactivity and catalytic activity on the surface. A better understanding of its origins will enable methods to control these rates. 相似文献
120.
Matthias Hilder Marina Lezhnina Marcus L. Cole Craig M. Forsyth Peter C. Junk Ulrich H. Kynast 《Journal of photochemistry and photobiology. A, Chemistry》2011,217(1):76-86
Europium and terbium complexes of ortho, meta and para substituted benzoate ligands including nitrobenzoate (NBA), aminobenzoate (ABA), hydroxybenzoate (OHBA) and methoxybenzoate (MeOBA) have been synthesised by metathesis reactions, carried out in aqueous media. The complexes were characterised by elemental, compositional and structural investigations, including microanalysis, EDTA titrations, differential thermal analysis, infra red spectroscopy, X-ray powder diffraction and single crystal structural analyses. Besides this, strong emphasis was on the determination of the optoelectronic properties of the compounds in the solid state. In this regard, reflectance, excitation and emission spectra were recorded. From these, the emission and excitation efficiencies were determined. The relative intensities as well as the splitting patterns of the 5D0 → 7FJ transitions in the europium emission spectra are discussed. 相似文献