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991.
D.L. Mills 《Applied Physics A: Materials Science & Processing》2007,87(3):427-431
This paper begins with some historical remarks regarding the author’s early interest in the use of electron energy loss spectroscopy
to probe dynamical phenomena on crystal surfaces. We then discuss the physical nature of the interactions responsible for
vibrational and spin waves losses, with attention to their role in related phenomena.
PACS 61.14.-x; 68.35.Ja; 68.49.Jk; 68.49.Uv 相似文献
992.
Y.-Q. Peng J.-H. Yang F.-P. Lu Q.-S. Yang H.-W. Xing X.-S. Li C.-A. Song 《Applied Physics A: Materials Science & Processing》2007,86(2):225-229
Based on the assumption of Gaussian energy distributions of the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO), analytical expressions of generalized Einstein relation in chemically doped organic semiconductor are developed, by approximation of Coulomb traps with a rectangle potential well. Numerical calculations show that traditional Einstein relations do not hold for chemically doped organic semiconductors. Similar to physical doping, the dependence of diffusion coefficient to mobility D/μ ratio on the carrier concentration has a maximum. An essential difference between chemical doping and physical doping is that, the D/μ ratio in chemically doped organic semiconductors depends not only on carrier concentration and doping concentration, but also on the applied electric field. PACS 71.20.Rv; 72.90.+y; 73.50.-h 相似文献
993.
Agrachev A. A. Gamkrelidze R. V. 《Proceedings of the Steklov Institute of Mathematics》2006,253(1):S4-S12
Proceedings of the Steklov Institute of Mathematics - 相似文献
994.
V. N. Sorokoumov S. N. Morozkina I. A. Balova 《Chemistry of Heterocyclic Compounds》2006,42(5):615-624
An investigation of the reaction of 1-lithio-1,3-diynes, generated in situ, with nitriles has been carried out. In the case
of aromatic nitriles 1-arylalk-1-ene-3,5-diynylamines are formed, which undergo dimerization and cyclization on isolation,
giving 3-(alka-1,3-diynyl)-4-(alk-2-ynyl)-2,6-diarylpyridines. The effect of the nature of the substituent in the benzonitrile
molecule on the selectivity of the reaction and the yield of the products has been determined. A scheme is proposed for the
conversions and the structures of the intermediates have been established.
__________
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 701–710, May, 2006. 相似文献
995.
C.E. Allmond V.P. Oleshko J.M. Howe J.M. Fitz-Gerald 《Applied Physics A: Materials Science & Processing》2006,82(4):675-678
Nanostructured powders have shown great promise for a variety of applications including chemical gas sensors, high surface
area supports for catalysis, tribology, chemical mechanical polishing, and optoelectronics. In this report, highly dispersed
Pd nanoparticles with a narrow size distribution, and mean diameter of 2±0.2 nm, were deposited at room temperature onto amorphous
carbon and oxide supports (TiO2, Al2O3) by pulsed-laser ablation of a Pd sputtering target. Depositions were performed in Ar at a back-fill pressure of 3 mTorr
after reaching a base pressure of 10-7 Torr. Populations of uniformly dispersed particles with an interparticle spacing of 3 to 10 nm were observed by high-resolution
transmission electron microscopy with little evidence of nanoparticle aggregation. The chemical compositions of individual
nanoparticles were confirmed by high spatial resolution energy-dispersive X-ray spectroscopy. 相似文献
996.
Within the perturbative-recombination model, the charge asymmetries in the D* +–D* ?, D* 0–D* 0, and D + s –D ? s yields are estimated under the kinematical conditions of the COMPASS experiment. Corrections that arise owing to the mass of a light quark in a charmed meson are taken into account. The yield of D + s meaons is predicted to be large in relation to the yield of D ? s mesons. 相似文献
997.
V. Yu. Topolov 《Physics of the Solid State》2006,48(7):1334-1341
The specific features of the coexistence of phases in heavily twinned crystals of the (1?x)Pb(Mg1/3Nb2/3)O3?xPbTiO3 system in the vicinity of the morphotropic phase boundary (0.30≤x≤0.40) are investigated. The phase transformations in crystals at x = const during cooling are considered at electric field strengths E=0 and 0.1 MV/m. The conditions of the formation of interphase boundaries (zero net strain planes) are determined for different first-order phase transitions. The results of calculating the tetragonal-monoclinic M C and monoclinic-monoclinic (M C –M A ) phase transitions are represented in the form of “twin state-interphase boundary” diagrams. The effect of a 90° domain (twin) structure of the tetragonal phase on the heterophase state associated with the presence of monoclinic phases is analyzed. 相似文献
998.
Epithio-substituted primary-tertiary dialkyl peroxides were prepared by treatment of tert-alkyl oxiranylmethyl peroxides with potassium thiocyanate and were tested as polymerization initiators in synthesis of light-resistant polystyrene. 相似文献
999.
V. S. Shmotin A. S. Knyazev A. I. Titkov A. N. Salanov O. V. Vodyankina L. N. Kurina 《Russian Journal of Applied Chemistry》2006,79(9):1458-1462
Surface morphology and catalytic properties of electrolytic silver crystals in partial oxidation of ethylene glycol into glyoxal were studied. 相似文献
1000.
D. N. Emel’yanov N. V. Volkova O. I. Sheronova Z. G. Chernorukova 《Russian Journal of Applied Chemistry》2006,79(8):1354-1359
The process of preservation of newspaper with aqueous solutions and dispersions of acrylic copolymers is considered from the instant of impregnation till removal of the polymeric preservative from paper. 相似文献