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91.
R. J. Temkin K. E. Kreischer W. J. Mulligan S. MacCabe H. R. Fetterman 《International Journal of Infrared and Millimeter Waves》1982,3(4):427-437
The design and operation of a 100 kW, 140 GHz pulsed gyrotron are reported. To our knowledge, this is the highest frequency at which high gyrotron output power (>-100 kW) has been achieved. Results are presented for gyrotron operation in the range of magnetic field from 4 to 7 T, voltage from 23 to 80 kV and current up to 7.5 A. Near a value of magnetic field of 5.4 T, and output power of 100 kW was obtained at 140.4 GHz in single mode operation in the TE031 resonator mode. 相似文献
92.
Polarized Raman spectra at 2, 80 and 300 K are reported for lattice and intramolecular modes in single crystals of tetrathiofulvalene, the donor molecule of the charge transfer complex TTF—TCNQ. In addition to these Raman features, a low-temperature emmision spectrum with associated sharp line structure is reported. 相似文献
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N. M. Klimenko K. V. Bozhenko E. V. Strunina E. A. Rykova O. N. Temkin 《Journal of Molecular Structure》1999,490(1-3):233-241
Ab initio calculations were performed for special points of the minimal energy pathways (MEP) of the nucleophilic addition reactions of the isolated H− anion, LiH molecule and Li+/H− ion pair to acetylene (A) and methylacetylene (MA) molecules, proceeding in accordance (M) and against (aM) the Markovnikov's rule. All structural parameters were optimized using the restricted Hartree–Fock (RHF) method. For the addition of H−, the 6-31++G* basis set was used and for the reactions of LiH and Li+/H− the 6-31G* basis set with the subsequent recalculation of single point energies, taking into account of electron correlation energy by means of the second-order Möller–Plesset perturbation theory at the MP2/6-31++G** level. The results of calculations demonstrate, that the energy characteristics of both M- and aM-additions with H− do not differ sufficiently (0.1–1.2 kcal/mol for the activation energies (ΔEa) and the reaction heats (ΔQ)). The substitution of the H atom by the CH3 group in A molecule results in practically the same values of ΔQ and ΔEa. On the contrary, for the LiH molecule and Li+/H− ionic pair, the M-addition is favorable (charge control). It is found that the presence of electrophile decreases the activation energy by 3–5 kcal/mol as compared with the addition of the isolated hydride ion H−. 相似文献
98.
Efremov G. E. Bovyrina E. A. Katsman E. A. Shamsiev R. S. Temkin O. N. 《Russian Chemical Bulletin》2019,68(7):1366-1375
Russian Chemical Bulletin - A kinetic model was developed for the reaction of ethylene oxidation to acetaldehyde by p-benzoquinone (Q) at 30 ℃ catalyzed by the cationic palladium(II)... 相似文献
99.
The effect of spatial dispersion on the electromagnetic properties of a metamaterial consisting of a three-dimensional mesh of crossing metallic wires is reported. The effective dielectric permittivity tensor epsilon(ij)(omega, k) of the wire mesh is calculated in the limit of small wavenumbers. The procedure for extracting the spatial dispersion from the omega versus k dependence for electromagnetic waves propagating in the bulk of the metamaterial is developed. These propagating modes are identified as similar to the longitudinal (plasmon) and transverse (photon) waves in a plasma. Spatial dispersion is found to have the most dramatic effect on the surface waves that exist at the wire mesh-vacuum interface. 相似文献
100.
A. Yu. Putin E. Yu. Bukina E. A. Katsman K. V. Trunilina I. V. Oshanina L. G. Bruk O. N. Temkin 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2013,87(3):465-472
The state of bromide complexes of palladium and copper in model solutions and under conditions of the conjugated catalytic synthesis of cyclohexanecarboxylic acid by the hydrocarboxylation of cyclohexene is studied by electron and infrared spectroscopy. It is found that during the conjugated process, copper exists in the form of copper(I) compounds, and palladium is present in the form of palladium(II) carbonyl complex. 相似文献