54 research outputs found
Marketing Metrics to the American Public: An Interview with Dr. Eugene Laczniak
One of the major problems confronting the metrication movement is the general lack of publicity and public awareness of the scope of the metric system. The work already performed as well as that still needed to be done to bring metrication to fruition needs considerable attention. The application of marketing principles and programs can have a potentially great effect on the success of the work of metric activists. During the course of this interview, conducted in late November, 1977, Dr. Eugene Laczniak suggests some of the ways in which marketing can be made to work for metrication; and he offers vital insights into the means by which metrication can become a fixed reality in American life, business, industry, government, and education
Ultrafast relaxation of photoexcited carriers in semiconductor quantum wires: A Monte Carlo approach
A detailed analysis of the cooling and thermalization process for photogenerated carriers in semiconductor quantum wires is presented. The energy relaxation of the nonequilibrium carrier distribution is investigated for the ‘‘realistic'' case of a rectangular multisubband quantum-wire structure. By means of a direct ensemble Monte Carlo simulation of both the carrier and the phonon dynamics, all the nonlinear phenomena relevant for the relaxation process, such as carrier-carrier interaction, hot-phonon effects, and degeneracy, are investigated. The results of these simulated experiments show a significant reduction of the carrier-relaxation process compared to the bulk case, which is mainly due to the reduced efficiency of carrier-carrier scattering; on the contrary, the role of hot-phonon effects and degeneracy seems to be not so different from that played in bulk semiconductors
Ab initio and photoemission study of correlation effects in thin films
We present the experimental and theoretical study of correlation effects in epitaxial SrRuO thin films. Experimentally, we have performed resonant ultraviolet photoemission spectroscopy (UPS) and angle-resolved hard x-ray photoemission spectroscopy (HAXPES) measurements. For resonant UPS, the two methods, Fano-profile fitting of constant initial state spectra and the energy distribution curves equidistant difference spectra, were used to extract Ru 4 partial spectral weight (PSW) in the valence band. We find Ru 4 PSW possessing a clearly pronounced coherent peak at the Fermi level together with angle-resolved HAXPES spectra demonstrating no difference in surface and bulk electronic structure. From comparison of experimental data with theoretical calculations done at density functional theory level, we conclude that SrRuO is a weakly correlated material and electronic structure of it can be consistently described employing first-principles approaches
Synthesis and structure elucidation of 1-aryl-substituted tetrahydropyridone derivatives
Mickevicius V, Vaickelioniene R, Mikulskiene G, Sewald N. Synthesis and structure elucidation of 1-aryl-substituted tetrahydropyridone derivatives. KHIMIYA GETEROTSIKLICHESKIKH SOEDINENII. 2005;(6):874-881.A series of 1-aryl-1,4,5,6-tetrahydro-4(1H)-pyridones having substituents in 2,3- and 2,3,5-positions was prepared from N-aryl-beta-alanines and ethyl acetoacetate or 2,4-pentanedione. Twelve tentative biologically active compounds were identified by the combination of H-1, C-13 and H-1/C-13 NMR spectroscopy. The extensive interest has been focused on the influence of substituents as well as on the number, attachment position and the nature of the substituents. The unknown shielding of the heterocyclic Ring on the aromatic carbon atoms was determined and the averaged chemical shift increments were successfully used for the assignment of the aromatic moiety of the studied compounds. The presence of two chiral elements in compounds 16, 17, 20-21 resulted in the mixture of diastereomers and double sets of the resonances in NMR spectra
Electronic structure of thin films studied by x-ray photoelectron spectroscopy and density functional theory
Enhancement-Mode Recessed Gate and Cascode Gate Junctionless Nanowire With Low-Leakage and High-Drive Current
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