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111.
Steady two‐dimensional natural convection in an inclined parallel‐walled channel was investigated numerically. The full elliptic forms of conservation equations were solved together and the velocity vectors, temperature contours and local and average Nusselt number distribution were obtained. The comparisons of local and average Nusselt number with published experimental and numerical results indicate very good agreement. Results are presented for a single aspect ratio, L/b=24, over the range of Rayleigh number of 3–1000 and angle of inclination 0–90°. The results indicate that the overall channel average Nusselt number is reduced as the inclination angle is increased. Significant reductions in the overall Nusselt number are exhibited at high angle of channel inclination. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
112.
Danika Locatelli Silvio Quici Stefania Righetto Dominique Roberto Francesca Tessore Geoffrey J. Ashwell Mukhtar Amiri 《Progress in Solid State Chemistry》2005,33(2-4):223-232
The new ligands (E)-4-[2-(4-(N-methyl-N-hexadecylaminophenyl)ethenyl]pyridine (L1) and 4′-(C6H4-p-N(Me)(hexadecyl))-2,2′:6′,2″-terpyridine (L2) were prepared along with their complexes [cis-Ir(CO)2ClL1], [fac-Os(CO)3Cl2L1], [ZnCl2L2] and [IrCl3L2]. Whereas these complexes show a large second-order nonlinear optical (NLO) response at the molecular level, similar to that of related organic alkylated salts as evidenced by the Electric Field Induced Second-Harmonic (EFISH) generation technique, their Langmuir–Blodgett (LB) film susceptibility is lower than that of the salts. 相似文献
113.
An asymptotic formula for the voltage potential in the case of a near-surface conductivity inclusion
Habib Ammari Hyeonbae Kang Karim Touibi 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2006,57(2):234-243
We rigorously derive an asymptotic expansion of the steady-state voltage potentials in the presence of a conductivity inclusion
of small volume that is close to a planar surface. This new formula is motivated by the practically important inverse problem
of imaging a conductivity inclusion near a planar interface.
Partly supported by ACI Jeunes Chercheurs (0693) from the Ministry of Education and Scientific Research, France.
Partially supported by grant R02-2003-000-10012-0 from the Korea Science and Engineering Foundation.
Received: December 2, 2003; revised: January 18, 2004 相似文献
114.
An efficient and highly chemoselective synthesis of symmetrical secondary amines via reductive amination of aldehydes with inexpensive and commercially available HMDS and sodium borohydride in high to quantitative yields is reported. 相似文献
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117.
Lin Y Böker A Skaff H Cookson D Dinsmore AD Emrick T Russell TP 《Langmuir : the ACS journal of surfaces and colloids》2005,21(1):191-194
The self-assembly of nanoparticles at fluid interfaces, driven by the reduction in interfacial energy, was investigated. With spherical, tri-n-octyl-phosphine-oxide covered cadmium selenide (CdSe) nanoparticles (1-8 nm), thermal fluctuations compete with the interfacial segregation giving rise to a size-dependent self-assembly of the particles. The structure of the nanoparticle assembly was studied using electron microscopy, atomic force microscopy, and X-ray scattering in situ, which indicate that the particles form a densely packed monolayer. The energetics of the adsorption of nanoparticles onto the interface was revealed by time-dependent fluorescence studies on a mixture of two different sized nanoparticles at the interface. The dynamics of the nanoparticles at the fluid interface, probed using fluorescence photobleaching methods, suggests a liquid-like behavior. The results have implications in the design of hierarchical self-assemblies of nanoparticles for the one-step fabrication of devices on multiple length scales. 相似文献
118.
Aziz-Ur-Rehman Malik A Riaz N Ahmad H Nawaz SA Choudhary MI 《Chemical & pharmaceutical bulletin》2005,53(3):263-266
A lignan and two acylphloroglucinols have been isolated from the ethyl acetate soluble fraction of the whole plant of Indigofera hetrantha. Their structures have been assigned on the basis of spectral analysis including 1D and 2D NMR techniques. Compounds 1-3 displayed promising inhibitory potential against enzyme lipoxygenase in concentration-dependent manner. 相似文献
119.
Spatially homogeneous random evolutions arise in the study of the growth of a population in a spatially homogeneous random environment. The random evolution is obtained as the solution of a bilinear stochastic evolution equation. The main results are concerned with the asymptotic behavior of the solution for large times. In particular, conditions for the existence of a stationary random field are established. Furthermore space-time renormalization limit theorems are obtained which lead to either Gaussian or non-Gaussian generalized processes depending on the case under consideration. 相似文献
120.