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961.
Effect of the molecular structure on the gas-surface scattering
studied by supersonic molecular beam
T. Kondo H. S. Kato T. Yamada S. Yamamoto M. Kawai 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2006,38(1):129-138
The experimental apparatus for investigating the gas-surface interaction has
been newly developed. The coherent length of the helium, the energy
resolution and the angular spread of the beam in the apparatus were
established as ω= 16 nm,
DE/E = 2.4%\Delta E/E = 2.4{\%}
and Δθ= 0.5○, respectively, through the
measurements of the time-of-flight of He beam and of the angular intensity
distributions of He scattered from LiF(001). The angular intensity
distributions of Ar, N2 and CO scattered from the LiF(001) surface
along the [100] azimuthal direction were then measured as a function of
incident translational energy. The effects of the molecular structural
anisotropy and center-of-mass position on the gas-surface inelastic
collision at the corrugated surface are discussed with predictions based on
a recently developed simple classical theory of the ellipsoid-washboard
model. 相似文献
962.
Toshiya Okazaki Takeshi Saito Koji Matsuura Satoshi Ohshima Motoo Yumura Yuji Oyama Riichiro Saito Sumio Iijima 《Chemical physics letters》2006,420(4-6):286-290
Band gap photoluminescence (PL) behaviors of single-walled carbon nanotubes (SWNTs) grown by the methods of chemical vapor deposition and pulsed-laser vaporization are investigated over the wide diameter range (≈0.8–1.4 nm). The peak intensity of the PL signals strongly depends on chirality and the ‘(2n + m) family type’ of SWNTs. Based on the PL results, a population analysis of these SWNTs is conducted by combining the calculated PL yields for each (n, m) tube. The results are directly compared with the histograms of diameter distributions estimated by the transmission electron microscope (TEM) observations to check the validity of the analysis. 相似文献
963.
Akihiro Ohta Masami Inoue Junichi Yamada Yasuhiko Yamada Teruo Kurihara Toshihiro Honda 《Journal of heterocyclic chemistry》1984,21(1):103-106
Some 2,3-diphenylpyrazine 1-oxides were heated with acetic anhydride to give the corresponding 2,3-di-acetoxy-2,3-dihydro-5,6-diphenylpyrazines. By X-ray diffraction analysis, the configuration of two acetoxyl groups was determined to be trans. 相似文献
964.
We succeeded in strictly transparent wavelength conversion by means of channel selection from multi-wavelength signals generated by sinusoidal modulation of input signal. Modulation-format-independent and bit-rate-independent wavelength conversion is achieved with small power penalty. 相似文献
965.
T. Yazawa J. J. Rabbers B. ten Haken H. H. J. ten Kate Y. Yamada 《Physica C: Superconductivity and its Applications》1998,310(1-4):36-41
The current density distribution of high temperature superconducting (HTS) tapes is modeled for the combined case of an alternating self and applied magnetic field. This numerical analysis is based on the two-dimensional Poisson equation for the vector potential. A one-dimensional current (z-direction) and a one-dimensional applied field (y-direction) are assumed. The vector potential is rewritten into an equation of motion for the current density J(x,y,t). The model covers the finite thickness of the conductor and an n-power E–J relation. The magnetic field dependence of Jc is also included in this E–J relation. A time-dependent two-dimensional current distribution that is influenced by the aspect ratio of the conductor and the material properties in E=f(J,B) is calculated numerically. The numerical results are compared with the experimental results for the AC loss of a tape driven by a transport current. Finally, a total AC loss factor is given for two cases in magnetic field direction, perpendicular and parallel to the conductor broad side. 相似文献
966.
A. Yamada Y. Makita H. Asakura T. Iida S. Kimura T. Matsumori S. Uekusa 《Applied Physics A: Materials Science & Processing》1991,53(2):102-108
Mg+ ions were implanted into highly pure InP grown by the liquid encapsulated Czochralski (LEC) method in which the Mg concentration [Mg] was varied between 1×1015 cm–3 and 3×1020 cm–3. Two annealing methods were used: furnace annealing (FA) up to 740° C and flash lamp annealing (rapid thermal annealing, RTA) up to 900° C. For characterization, photoluminescence (PL) spectra were measured between 2K and room temperature together with Raman scattering measurements at room temperature. An emission designated by g, which was attributed to a novel energy state of an isolated acceptor, was found to be produced for a rather low value of [Mg]. In addition, a broad emission denoted by [g–g], which was ascribed to acceptor-acceptor pairs, was observed below bound exciton emissions for moderate values of [Mg]. These features were quite similar to those previously observed in acceptor-doped GaAs when the background concentration of donors is extremely low. Two additional novel emissions located far below the band-to-acceptor emission were also obtained, and each showed a remarkable energy shift towards lower energy with increasing [Mg]. The binding energies of these emissions were estimated from the temperature dependence of PL spectra and the results suggest that they are complex-type radiative recombination centers, presumably donor-acceptor-type centers. A strong broad emission centered near the band-to-acceptor emission was observed for [Mg]=3×1020 cm–3. This observation indicates a formation of a new material between In, P and Mg, which was also attested by the appearance of a new TO-like Raman signal for [Mg] greater than 1×1019 cm–3. A substantial difference of PL and Raman spectra was revealed for the two annealing methods, suggesting that the annealing behaviour of ion-implanted InP should be investigated more extensively in order to establish reliable annealing procedures.Dedicated to H.-J. Queisser on the occasion of his 60th birthday 相似文献
967.
Analysis of antimony around the abandoned Tsugu mine in Aichi Prefecture by neutron activation analysis 总被引:1,自引:0,他引:1
Y. Katayama A. Misawa N. Yamada S. Yachi H. Muto T. Aoki Y. Kawabata M. Nagai 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(2):283-286
At Tsugu mine in Aichi Prefecture, antimony was mined and smelted until 1956. The amounts of antimony present in the soil
of the abandoned mine were measured to enable us to detect any traces of the operation of the mine and to measure the level
of environmental contamination with antimony. The quantity of antimony in rings of hinoki and sugi was also measured to obtain
information about chronological changes in environmental conditions. The quantity of antimony in the samples was determined
by INAA. The antimony concentrations in eight soil samples at different points in the Tsugu mine area were 8–17,000 ppm. 相似文献
968.
969.
W. Bartel L. Becker D. Cords R. Felst D. Haidt H. Junge G. Knies H. Krehbiel P. Laurikainen K. Meier R. Meinke B. Naroska J. Olsson D. Schmidt P. Steffen G. Dietrich J. Hagemann S. Yamada 《Physics letters. [Part B]》1985,157(4):340-344
Distributions of particles in three-jet events from e+e? → hadrons are compared with different fragmentation schemes, i.e. the Lund string model, independent parton fragmentation and QCD shower models. Effects specific to the string scheme, which have been seen in the data, are also reproduced by QCD shower models if soft gluon interference effects are included. 相似文献
970.
K. Yamada N. Miura C. Hamaguchi 《Applied Physics A: Materials Science & Processing》1989,48(2):149-153
Chaotic conductivity oscillations were observed in n-Si in a narrow freeze-out temperature range between 26 K and 34 K in a pulsed high magnetic field of about 18 T. It was found that the chaotic behaviour can be drastically influenced by the magnetic field. Period-doubling bifurcations were found in these chaotic oscillations and the routes to the chaos were determined. The attractor dimensions of the chaos converged to around 1.1 to 2.3 depending on the applied electric fields. The frequency dependence of the power spectrum of the oscillations was approximately 1/f
2. 相似文献