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21.
Musubu Ichikawa Nobuyasu Hiramatsu Norimasa Yokoyama Tetsuzo Miki Susumu Narita Toshiki Koyama Yoshio Taniguchi 《固体物理学:研究快报》2007,1(1):R37-R39
We demonstrate that a bipyridyl substituted oxadiazole (Bpy‐OXD) shows high electron mobility that reached above 10–3 cm2/Vs. We believe that the high mobility results from both the hybrid molecular structure of the two electron‐accepting units: bipyridyl and oxadiazole, and the planar molecular structure based on its lack of sterically hindered bulky substituent. The computational analysis elucidates that the amorphous nature of Bpy‐OXD in thin‐film state probably results from the polymorphic effect in isolated state and the volume effect in solid state. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
22.
Paper deals with quantum chemical modeling of the optical absorption spectra of 6-fluoro, 7-trifluoromethyl, 6-cyano, 6-carboethoxy and 6-tert-butyl derivatives of 1-phenyl-3-methyl-1H-pyrazolo[3,4-b]quinoline. The calculations are performed by means of the semiempirical quantum chemical methods (AM1 or PM3) applied to the equilibrium molecular conformation in vacuo (T = 0 K) or molecular dynamic (MD) trajectories as obtained within fragmental or total MD simulations at T = 300 K. The results of these calculations are compared with the measured spectra of optical absorption. The quantum chemical analysis show that the dynamics of the methyl, trifluoromethyl, carboethoxy and tert-butyl groups practically does not influence the absorption spectra whereas the strongest their modifications are found to be related with dynamics of the aromatic group. The semiempirical method AM1 in combination with MD simulations gives for all dyes the best agreement between the calculated and measured spectral positions of absorption bands. In most cases the quantum chemical calculations describe properly the trends of their changes depending on the lateral substituent. 相似文献
23.
I.V. Krasnov 《Physics letters. A》2008,372(17):3118-3123
The possibility of a new application of optical molasses for viscous confinement and control of the state of ultracold electron-ion neutral plasma containing ions with quantum transition resonant with respect to the laser radiation has been shown. This viscous confinement scheme is based on the action of radiation damping force upon plasma ions in the strong field of standing light wave with large positive (“blue”) frequency detuning from resonance. 相似文献
24.
H.-T. Jung 《Applied physics. B, Lasers and optics》2000,70(2):237-242
The optical, thermal, and structural behavior of a laser-irradiated dye-in-polymer bilayer film consisting of an elastic and
a plastic layer was investigated by a computer modeling and recording experiment. The results of numerical calculations describe
absorption of optical energy in the recording layers, the heat flow, and the resultant bump formation throughout the multilayer.
Recording performance of the material is strongly affected by the dye concentration and the thickness of the plastic layer.
The calculated and measured properties of the media are compared, and the relationship between the dye concentration, thickness
of plastic layer, and thermal, structural, and recording performance are described.
Received: 9 March 1999 / Revised version: 10 May 1999 / Published online: 29 July 1999 相似文献
25.
T. Nakamura 《The European Physical Journal A - Hadrons and Nuclei》2002,13(1-2):33-37
We present the recent experimental results on the 6He structure studied by the 6Li(t, 3He)6He reaction at 336 MeV. Above the conspicuous peaks for ground and first excited states for 6He, we have observed a broad structures at E
x∼ 5 MeV, and E
x∼ 15 MeV. The angular distribution of this structure exhibits the dominance of a ΔL = 1 transition, indicating the existence of intruder dipole states at low excitation energies in 6He. A slight admixture of positive-parity states in this structure has been indicated as well.
Received: 1 May 2001 / Accepted: 4 December 2001 相似文献
26.
We apply the kT factorization approach to deal with the B→K transition form factor with tensor current in the large recoil regions. Main uncertainties for the estimation are discussed and we obtain FT^B→K (0) = 0.25±0.01±0.02, where the first error is caused by the uncertainties from the pionic wavefunctions and the second is from that of the B-meson wavefunctions. This result is consistent with the light-cone sum rule results obtained in the literature. 相似文献
27.
Marian ?enkiewicz Marta Rauchfleisz Julian Polański W?odzimierz Engelgard 《Applied Surface Science》2007,253(22):8992-8999
The aim of this article was to show the effects of an electron radiation dose and presence of a compatibilizer on the oxidation of composites made of blends of low-density polyethylene (LDPE), high-density polyethylene (HDPE), polypropylene (PP), polystyrene (PS), and poly(ethylene terephthalate) (PET) as well as of blends of LDPE, HDPE, and PP. As the compatibilizers, the styrene-ethylene/butylene-styrene elastomer grafted with maleic anhydride (SEBS-g-MA) and trimethylol propane trimethylacrylate (TMPTA) were used; they were added in the amounts of 5, 10, and 15 wt% and 1, 2, and 3 wt%, respectively. The oxidation of the surface layer (SL) was investigated by the X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). It was found that the extent of the composite oxidation increased with the increasing dose of the electron radiation. The addition of the compatibilizers enhanced the oxidation of the SL but hindered the oxidation of the bulk of the material. 相似文献
28.
Zhiqiang Gao Shujing Peng Jie Sun Lan Yao Yiping Qiu 《Applied Surface Science》2009,255(17):7683-7688
This study is designed to systematically investigate how various factors, such as treatment duration, output power, oxygen gas flux, jet to substrate distance, and moisture regain, influence atmospheric pressure plasma etching rate of polyamide 6 (PA 6) films. The etching rate increased as the output power, oxygen gas flux, and moisture regain increased. As the treatment time increased, the etching rate increased first and then decreased. When the substrate was too close or too far from the nozzle, the etching rate was almost not measurable. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) show an increased surface roughness after the plasma treatment. X-ray photoelectron spectroscopy (XPS) shows a decreased carbon content and an increased oxygen content after the plasma treatment. T-peel strength shows an improved bonding strength between the PA 6 films and an adhesive tape after the plasma treatment. 相似文献
29.
L.Y. Zhu 《Journal of Non》2009,355(1):68-207
ZrxTi1−xO2 (x = 0.1-0.9) fibers were prepared by the sol-gel dry-spinning method. Polyacetylacetonatozirconium (PAZ) and tetrabutyl titanate (C16H36O4Ti) were used as raw materials. The green fibers were obtained from the amorphous spinnable solution and then heat-treated to convert into polycrystalline fibers. The main phase changes from TiO2 to zirconium titanate (ZT) and then tetragonal ZrO2 with increasing ZrO2 content. The crystallization temperature varied with the molar ratio of Zr:Ti. The heat-treated fibers at 1050 °C have few pores and no cracks with diameters of 10-20μm and lengths of 1-5 cm. 相似文献
30.
E. Nir Ch. Plützer K. Kleinermanns M. de Vries 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,20(3):317-329
The vibronic spectra of laser desorbed and jet cooled guanine (G) adenine (A), and cytosine (C) consist of bands from four,
two and two major tautomers respectively, as revealed by UV-UV and IR-UV double resonance spectroscopy. The vibronic spectrum
of adenine around 277 nm consists of weak nπ* and strong ππ* transitions, based on IR-UV and deuteration experiments. Precise ionization potentials of G and A were determined with 2-color,
2-photon ionization. We also measured vibronic and IR spectra of several base pairs. GC exhibits a HNH ... OH/NH ... N/C=O ... HNH bonding similar to the Watson-Crick GC base pair but with C as enol tautomer. One GG isomer exhibits non-symmetric hydrogen
bonding with HNH ... N/NH ... N/C=O ... HNH interactions. A second observed GG isomer has a symmetrical hydrogen bond arrangement with C=O ... NH/NH ... O=C bonding. Two CC isomers were observed with symmetrical C=O ... NH/NH ... O=C bonding and nonsymmetrical C=O ... HNH/NH ... N interaction, respectively. Guanosine (Gs), 2-DeoxyGs und 3-DeoxyGs each exhibit only one isomer in the investigated wavelength
range around 290 nm with a strong intramolecular sugar(5-OH) ... enolguanine(3-N) hydrogen bond.
Received 16 June 2002 / Received in final form 15 July 2002 Published online 13 September 2002 相似文献