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61.
62.
The use of a continuously tunable CO2 laser to optically pump the NH3 laser via previously inaccessible absorption lines is described. Efficient laser action has thus been achieved in the 11–13 μm region on transitions formerly only obtained in buffered mixtures. 相似文献
63.
InGaAlP/GaAs red light-emitting diodes (LEDs) with a sub-wavelength moth-eye structure at the output surface were demonstrated. A high-resolution polydimethylsiloxane (h-PDMS) casting material was used for the fabrication of the moth-eye structure from polymer template which was fabricated by hot embossing. The h-PDMS mold was subsequently used to transfer the nanostructure on the output surface of the LED by soft embossing. We succeeded in forming a close packed hexagonal array of hemispheres with 300 nm pitch, and 128 nm depth. With 10 mA driving current, the corresponding efficiency (cd/A) of moth-eye-structured light-emitting diodes was enhanced by 36% compared with those of non-patterned LEDs. The experimental results are in agreement with the results of a theoretical analysis of the effect of the moth-eye structure. 相似文献
64.
Focsa C Poclet A Pinchemel B Le Roy RJ Bernath PF 《Journal of Molecular Spectroscopy》2000,203(2):330-338
The A'(1)Pi-X(1)Sigma(+) near-infrared system of CaO was observed for the first time at high resolution using a Fourier transform spectrometer. The A'(1)Pi-X(1)Sigma(+) chemiluminescence was excited in a Ca + N(2)O flame produced in a Broida-type oven. More than 3000 rotational lines, classified into 19 bands involving the A'(1)Pi 0 = v' = 3 and the X(1)Sigma(+) 1 = v" = 7 vibrational levels were measured in the 4000-10 000 cm(-1) region with a precision of 0.005 cm(-1). The X(1)Sigma(+) (v = 0, 1) millimeter-wave and X(1)Sigma(+) (v = 0-3) infrared data available in the literature were merged with our new electronic data in order to obtain improved Dunham constants for the ground state of CaO. Very peculiar perturbations are observed in the higher vibrational levels of the A'(1)Pi state, so the upper levels of transitions with v' = 2 and 3 were represented by term values in our least-squares analysis. The interaction of the A'(1)Pi (v >/= 2) levels with the nearby b(3)Sigma(+) (v-2) levels has been detected. An extended set of A'(1)Pi (v = 0-3) data has been obtained which is suitable for use in a future multistate deperturbation analysis of the a(3)Pi approximately A'(1)Pi approximately b(3)Sigma(+) approximately A(1)Sigma(+) complex of excited states. The new near-infrared spectra of the A'(1)Pi-X(1)Sigma(+) transition of CaO also permits the first direct high-resolution linkage between the orange and green systems and the near-infrared bands. Copyright 2000 Academic Press. 相似文献
65.
Wong KL Chu MS Luce TC Petty CC Politzer PA Prater R Chen L Harvey RW Austin ME Johnson LC La Haye RJ Snider RT 《Physical review letters》2000,85(5):996-999
Experimental evidence is reported of an internal kink instability driven by a new mechanism: barely trapped suprathermal electrons produced by off-axis electron cyclotron heating on the DIII-D tokamak. It occurs in plasmas with an evolving safety factor profile q(r) when q(min) approaches 1. This instability is most active when ECCD is applied on the high field side of the flux surface. It has a bursting behavior with poloidal/toroidal mode number = m/n = 1/1. In positive magnetic shear plasmas, this mode becomes the fishbone instability. This observation can be qualitatively explained by the drift reversal of the barely trapped suprathermal electrons. 相似文献
66.
LeClair P Swagten HJ Kohlhepp JT van De Veerdonk RJ de Jonge WJ 《Physical review letters》2000,84(13):2933-2936
Co/Al2O3/Co magnetic tunnel junctions with an interfacial Cu layer have been investigated with in situ growth characterization and ex situ magnetotransport measurements. Cu interlayers grown on Co give an approximately exponential decay of the tunneling magnetoresistance with xi approximately 0.26 nm while those grown on Al2O3 have a decay length of 0.70 nm. The difference in decay lengths can be explained by different growth morphologies, and in this way clarifies a present disagreement in the literature. For monolayer coverage of Cu, we show that the tunneling spin polarization is suppressed by at least a factor of 2 compared to Co and beyond approximately 5 ML it becomes vanishingly small. 相似文献
67.
Gerard M. Anderson Javed Iqbal David W.A. Sharp John M. Winfield James H. Cameron Alasdair G. McLeod 《Journal of fluorine chemistry》1984,24(3):303-317
The redox properties of molybdenum, tungsten and uranium hexafluorides in acetonitrile at 298 K have been compared with other redox couples using cyclic voltammetry, and by carrying out appropriate redox reactions under carefully controlled conditions. The order of oxidizing ability established is UF6 > MoF6 > NO+1 > solvated Cu2+ ? WF6. The position of the solvated Tl3+ cation probably lies between MoF6 and Cu2+ Reactions which occur in the Cu metal/solvated Cun+ (n = 1 or 2)/WF6 system are accounted for by redox and fluoride-ion-transfer equilibria. 相似文献
68.
Gerard M. Anderson James H. Cameron A.Graham Lappin John M. Winfield Alexander McAuley 《Polyhedron》1982,1(5):467-470
Reduction of the solvated copper(II) cation by trimethyl phosphite in acetonitrile occurs via a short-lived purple intermediate believed to be a copper(II)-phosphite complex. 相似文献
69.
Le Roy RJ 《Journal of Molecular Spectroscopy》1999,194(2):189-196
A new way of representing vibration-rotation term values for multiple isotopomers of a given electronic state of a diatomic molecule is presented which resolves problems associated with the way the conventional combined isotopomer expansion represents the atomic mass-dependent JWKB and Born-Oppenheimer breakdown correction terms. Its application to infrared and microwave data for HF and DF yields new Dunham expansion coefficients and Born-Oppenheimer breakdown correction terms for this species. This procedure is implemented in a generally available computer program for fitting to various types of data involving one or several electronic states of multiple isotopomers of a diatomic molecule. Copyright 1999 Academic Press. 相似文献
70.