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71.
The pure rotational transitions of HN2+ and DN2+ in the first excited vibrational states for all the fundamental vibrational modes have been observed in the range of 300-750 GHz. The molecular constants determined are much more accurate compared with those obtained from the infrared spectroscopy. The equilibrium rotational constants, Be = 46832.45 (71) MHz for HN2+ and Be = 38708.38 (58) MHz for DN2+, have been determined by correcting for the higher-order vibration-rotation interaction effects, γij, obtained by an infrared investigation. The equilibrium bond lengths are derived from these equilibrium rotational constants: re(H-N) = 1.03460 (14) Å and re (N-N) = 1.092698 (26) Å. 相似文献
72.
Otsuki J Arai Y Amano M Sawai H Ohkita M Hayashi T Hara M 《Langmuir : the ACS journal of surfaces and colloids》2008,24(11):5650-5653
Regardless of the absence of alkyl chains and conventional hydrogen bonding sites as well as its small size, 2,6-diethynylpyridine forms an ordered array at the interface between 1-phenyloctane and highly oriented pyrolytic graphite (HOPG) under room temperature conditions, as revealed by scanning tunneling microscopy. We propose a model for the superperiodic molecular arrangement with reference to the bulk crystal structure, in which the surface pattern is governed by weak C-H...N and C-H...pi hydrogen bonds as well as the periodic potential of the underlying graphite surface. 相似文献
73.
74.
Ryoichi S. Amano Mohsen M. Abou-Ellail Samer Elhaw Mohamed Saeed Ibrahim 《Heat and Mass Transfer》2013,49(9):1243-1260
In this work a prediction was numerically modeled for a catalytically stabilized thermal combustion of a lean homogeneous mixture of air and hydrogen. The mixture flows in a narrow rectangular channel lined with a thin coating of platinum catalyst. The solution using an in-house code is based on the steady state partial differential continuity, momentum and energy conservation equations for the mixture and species involved in the reactions. A marching technique is used along the streamwise direction to solve the 2-D plane-symmetric laminar flow of the gas. Two chemical kinetic reaction mechanisms were included; one for the gas phase reactions consisting of 17 elementary reactions; of which 7 are forward–backward reactions while the other mechanism is for the surface reactions—which are the prime mover of the combustion under a lean mixture condition—consisting of 16 elementary reactions. The results were compared with a former congruent experimental work where temperature was measured using thermocouples, while using PLIF laser for measuring water and hydrogen mole fractions. The comparison showed good agreement. More results for the velocities, mole fractions of other species were carried out across the transverse and along the streamwise directions providing a complete picture of overall mechanism—gas and surface—and on the production, consumptions and travel of the different species. The variations of the average OH mole fraction with the streamwise direction showed a sudden increase in the region where the ignition occurred. Also the rate of reactions of the entire surface species were calculated along the streamwise direction and a surface water production flux equation was derived by calculating the law of mass action’s constants from the concentrations of hydrogen, oxygen and the rate of formation of water near the surface. 相似文献
75.
The 212 − 111 line of H2D+ at 2.363 THz that was detected toward Sgr B2 and identified based on a calculated line frequency has been measured in the laboratory precisely by using a tunable far-infrared spectrometer. All the available THz lines and known millimeter- and submillimeter-wave lines together with the combination differences derived from the infrared transitions are fitted to the Watson effective Hamiltonian. A set of improved molecular constants are obtained. 相似文献
76.
Let K be either the rational number field or an imaginary quadratic field. We give irrationality results for the number , where q (∣q∣ > 1) is an integer in K, r∈ K
× (∣r∣ < ∣q∣), and with q
n
≠ r
l (n ≥ 1).
Authors’ addresses: Kenji Amano, NS solutions Corporation, 2-27-1 Shinkawa, Chuo-ku, Tokyo 104-0033, Japan; Yohei Tachiya,
Department of Mathematics, Keio University, Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan 相似文献
77.
M. Esmaeili M. Gholami H. Haratizadeh B. Monemar P. O. Holtz S. Kamiyama H. Amano I. Akasaki 《Opto-Electronics Review》2009,17(4):293-299
We report the results from detailed optical spectroscopy from MOCVD grown GaN/AlGaN multiple quantum wells (MQWs), as opposed
to most previous studies where MBE was employed by means of photoluminescence (PL) technique. In this paper we will present
theoretical and experimental results demonstrating how polarization induced electric fields and bound interface charges in
GaN/AlGaN MQWs affect the emission peak energy, PL line shape, as well as the emission line width. Theoretically estimated
fields in this work are consistent with experimental data. Transition energy of the heavy hole and electron ground state Ee-hh
in GaN/AlGaN MQWs were calculated and it is found that it stays in good agreement with the experimental data. 相似文献
78.
Collisional relaxation among rotational levels of NH3 studied by infrared-microwave double resonance
Double-resonance signals induced by molecular collisions are observed in 25 inversion transitions of NH3. It is found that the collision-induced transitions do not necessarily occur in accordance with the dipole-type selection rule reported previously. 相似文献
79.
80.