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21.
Wavelet processing and digital interferometric contrast to improve reconstructions from X‐ray Gabor holograms 下载免费PDF全文
Juan C. Aguilar Masaki Misawa Kiyofumi Matsuda Yoshio Suzuki Akihisa Takeuchi Masato Yasumoto 《Journal of synchrotron radiation》2018,25(3):808-817
In this work, the application of an undecimated wavelet transformation together with digital interferometric contrast to improve the resulting reconstructions in a digital hard X‐ray Gabor holographic microscope is shown. Specifically, the starlet transform is used together with digital Zernike contrast. With this contrast, the results show that only a small set of scales from the hologram are, in effect, useful, and it is possible to enhance the details of the reconstruction. 相似文献
22.
In the atmospheric correction of satellite data in the visible and near-infrared bands, it is necessary to remove the adjacency effect due to the reflection from contiguous pixels. Evaluation of the influence of aerosol vertical distributions on the adjacency effect is done by calculating the single-scattering light intensity which, after the reflection at the ground surface, reaches the satellite sensor via a single scattering with a molecule or an aerosol particle. In the simulation, we assume aerosol vertical profiles similar to those used in the MODTRAN radiation transfer code, and those having a mixed layer with a uniform value of the aerosol extinction coefficient. We assume for the ground surface a simple model representing a border of land/sea surfaces. In spite of the single scattering approximation, it is confirmed that even if the optical thickness is the same, we have a larger adjacency effect when the extinction coefficient is large at higher altitudes. We also discuss the dependence of the adjacency effect on the aerosol optical thickness and that on the difference in the reflectances of the land and sea surfaces along the border. 相似文献
23.
N. Nishida R.S. Hayano K. Nagamine T. Yamazaki J.H. Brewer D.M. Garner D.G. Fleming T. Takeuchi Y. Ishikawa 《Solid State Communications》1977,22(4):235-239
In recent positive-muon spin rotation experiment at TRIUMF on single crystal Fe, a clear temperature dependent change has been observed, for the first time, both in frequency and depolarization rates from 300 K down to 23 K. The μ+ depolarization was explained by the μ+ diffusion through inhomogeneous dipolar fields and the diffusion constant was found to obey an Arrhenius law (activation energy 17 meV) above 70 K but surprisingly deviated from this at lower temperatures, indicating quantum diffusion. We have also found that the μ+ hyperfine field has a temperature dependence slightly stronger than that of the magnetization. 相似文献
24.
S. Ota S. Shimoura H. Iwasaki M. Kurokawa S. Michimasa N. Aoi H. Baba K. Demichi Z. Elekes T. Fukuchi T. Gomi S. Kanno S. Kubono K. Kurita H. Hasegawa E. Ideguchi N. Iwasa Y.U. Matsuyama K.L. Yurkewicz T. Minemura T. Motobayashi T. Murakami M. Notani A. Odahara A. Saito H. Sakurai E. Takeshita S. Takeuchi M. Tamaki T. Teranishi Y. Yanagisawa K. Yamada M. Ishihara 《Physics letters. [Part B]》2008
25.
Dr. Sudhir Kumar Keshri Dr. Waka Nakanishi Dr. Atsuro Takai Prof. Dr. Tomoya Ishizuka Prof. Dr. Takahiko Kojima Prof. Dr. Masayuki Takeuchi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(58):13288-13294
The design and synthesis of a tweezer-shaped naphthalenediimide (NDI)–anthracene conjugate ( 2NDI ) are reported. In the structure of the closed form (πNDI ⋅⋅⋅ πNDI stack) of 2NDI , which was elucidated by single-crystal XRD, the existence of C−H ⋅⋅⋅ O hydrogen bonding involving the nearest carbonyl oxygen atom of an NDI unit was suggested. The tunability of πNDI ⋅⋅⋅ πNDI interactions was studied by means of UV/Vis absorption, fluorescence and NMR spectroscopy and molecular modelling. This revealed that the πNDI ⋅⋅⋅ πNDI interactions in 2NDI affect the absorption and emission properties depending on the temperature. Furthermore, in polar solvents, 2NDI prefers the stronger πNDI ⋅⋅⋅ πNDI stack, whereas the πNDI ⋅⋅⋅ πNDI interaction is diminished in nonpolar solvents. Importantly, the conformational variations of 2NDI can be reversibly switched by variation in temperature, and this suggests potential application for fluorogenic molecular switches upon temperature changes. 相似文献
26.
Y. nuki R. Settai F. Honda T. Takeuchi N. Tateiwa T.D. Matsuda E. Yamamoto Y. Haga H. Harima 《Physica C: Superconductivity and its Applications》2009,469(15-20):868-873
The heavy fermion state in the f-electron systems is due to competition between the RKKY interaction and the Kondo effect. The typical compound is CeCu6. To understand the electronic state, we studied the Fermi surface properties via the de Haas–van Alphen (dHvA) experiment and energy band calculation for CeSn3,CeRu2Si2,UPt3, and nowadays, transuranium compounds. Pressure is also an important technique to control the electronic state. The Néel temperature TN decreases with increasing pressure P and becomes zero at the critical pressure for . The typical compound is an antiferromagnet CeRhIn5, which we studied from the dHvA experiment under pressure. A change of the 4f-electronic state from localized to itinerant is realized at , revealing the first-order phase transition, together with a divergent tendency of the cyclotron mass at Pc. It is stressed that appearance of superconductivity in CeRhIn5 is closely related to the heavy fermion state. It is also noted that the parity-mixed novel superconducting state might be realized in a pressure-induced superconductor CeIrSi3 without inversion symmetry in the crystal structure. 相似文献
27.
Tomohito Kameda Hidenori Takeuchi Toshiaki Yoshioka 《Journal of Physics and Chemistry of Solids》2009,70(7):1104-1083
New layered magnesium hydroxides whose brucite layers had been bridged with malate2− and tartrate2− were prepared by dropwise addition of Mg(NO3)2 to malate and tartrate solutions at a constant pH of 10.5. Malate2− and tartrate2− may have been also absorbed on the surfaces of hydroxides. In the case of using citrate solution, Mg(OH)2 absorbed with citrate3− was produced. These materials were found to take up Cu2+ rapidly from an aqueous solution at pH 5.0. Copper uptake by precipitates is attributed to the formation of chelate complexes of Cu2+ with citrate3−, malate2−, and tartrate2−. 相似文献
28.
Geoffrey B Edwards Kaoru Yamanouchi Kozo Kuchitsu Masaaki Sugie Harutoshi Takeo Chi Matsumura Keiichiro Ogawa Yoshito Takeuchi 《Journal of Molecular Spectroscopy》1985,111(2):301-319
The microwave spectrum of 1-pyrroline has been measured from 8 to 48 GHz. The transitions have been assigned to those of the ground state and the four lowest excited states of the ring-puckering vibration of monomer, which is a five-membered ring molecule with one CN double bond. The trimer, which exists in the liquid phase, has not been detected in the gas phase. The geometrical structure of the monomer has been estimated by an ab initio calculation and the trimer by a molecular mechanics calculation. The former is consistent with the experimental rotational constants. A gas-phase infrared spectrum has also been measured, and the ring-puckering potential has been determined by an analysis of the combination bands of the ring-puckering mode and the ring-stretching modes. The potential is described using a puckering coordinate, z, as V(z) = az2 + bz4, where and ; these values are intermediate of the corresponding values for cyclopentene and 1-pyrazoline. The nuclear quadrupole coupling constants, χaa = ?4.39(10), χbb = 1.04(10), and χcc = 3.35(10) MHz, have been determined by an analysis of well-resolved hyperfine splittings. These constants have been reproduced by an ab initio calculation with a 4-31G(N1) basis set. 相似文献
29.
Kazuo Takeuchi Junsuke Yabumoto Yoshiki Okada Terunao Kawai Rahman M. Montajir Yuichi Goto 《Journal of nanoparticle research》2005,7(2):287-293
A new dual-type differential mobility analyzer (dual-type DMA) was developed in order to detect transient number concentrations of airborne nanoparticles with diameters centralized at around 10 nm (for nuclei mode particles) and 100 nm (for accumulation mode particles) in automobile exhaust gas. The apparatus divides the gas sample into two parts, and each part is sent through one of two coaxially nested sections for analysis. For the scanning mode measurement, the nanoparticles are charged by 241Am and their size distributions are determined by varying the applied voltage over 2 min. The transient mode measurement, on the other hand, fixes the voltages for the two sections at peaks near 10 and 100 nm in order to monitor the transient behavior of the exhaust nanoparticles. The measurement principles and design of the dual-type DMA are detailed and the results for time response experiments are presented using model nanoparticles charged by a corona charger. The transient concentrations of the nuclei mode and the accumulation mode particles from a diesel engine were shown to be detected by this method, when 241Am was used for charging the particles. 相似文献
30.
Yoshinori Matsuo Sang-Jin Sin Shingo Takeuchi Takuya Tsukioka Chul-Moon Yoo 《Nuclear Physics B》2009,820(3):593-619
In the previous paper we studied the transport coefficients of quark–gluon plasma in finite temperature and finite density in vector and tensor modes. In this paper, we extend it to the scalar modes. We work out the decoupling problem and hydrodynamic analysis for the sound mode in charged AdS black hole and calculate the sound velocity, the charge susceptibility and the electrical conductivity. We find that Einstein relation among the conductivity, the diffusion constant and the susceptibility holds exactly. 相似文献