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51.
52.
Tahara T Awatsuji Y Shimozato Y Kakue T Nishio K Ura S Kubota T Matoba O 《Optics letters》2011,36(16):3254-3256
We propose single-shot digital holography which is capable of simultaneously capturing both the information of multiple phase-shifted holograms and the distribution of the polarization. In this technique, a single image sensor records both the information required for phase-shifting interferometry and that of the polarization states of objects using an array of polarizers. The essence of the technique is the capability of imaging the distribution of the polarization of three-dimensional objects with a single-shot exposure by using the space-division multiplexing of holograms. The validity of the proposed technique was confirmed by the preliminary experiments. 相似文献
53.
54.
Naoto Nishio Kentaro Yamana Yasutaka Yamaguchi Takehiko Inaba Koji Kuroda Tadashi Nakajima Kouhei Ohno Hideo Fujimura 《国际流体数值方法杂志》2010,63(12):1435-1447
In this study, the whole process of liquid droplet impact onto a liquid surface up to the consequent formation of the central column was simulated using the smoothed particle hydrodynamics method (SPH), and compared with an experiment using a high‐speed video camera. The surface tension tensor for the particle‐based expression was adequately included as the gradient of the surface tension and that enabled the simulation leading to the formations of crater and crown as well as the consequent central column. The simulated time series of the crater depth and diameter and crown height corresponded quantitatively well with the experimental result up to the rebound motion while discrepancies remained as a lower central column height in the simulation, and this seemed to be ascribed to the difficulty in realizing the complex surface structure that inevitably appeared in the fast rebound motion. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
55.
Masaharu Okazaki Taizo Ono Kenji Komaguchi Nobuaki Ohta Haruhiko Fukaya Kazumi Toriyama 《Applied magnetic resonance》2009,36(1):89-95
Room temperature fluorine electron nuclear double resonance (ENDOR) has been successfully observed for several superstable
fluorocarbon radicals ·C(C2F4R)(i-C3F7)2 in solution. Three radicals were employed in which CF3, F, and O-c-C6F10SO3C2F5 were introduced as R, and all the hyperfine couplings (hfcs) obtained by ENDOR were assigned with the help of ESR simulation
and ab initio MO calculation. In case of ·C(i-C3F7)3 large 13C and considerable β-fluorine couplings suggest the nonplaner arrangement for the central and three carbons at the β-position, in spite of the
fact that all the methyl fluorine show the same hfc. Therefore, a rapid puckering motion along the C3 axis together with the methyl rotation should average the hfc’s of the 18 fluorine nuclei to give the same value. When one
of the CF3 groups is substituted with an F nucleus, the five CF3 groups give two hfc values, suggesting some dynamics still exists for the molecular frame. When a large group, O-c-C6F10SO3C2F5, is substituted for CF3, all the five CF3 groups become nonequivalent and the ENDOR signal becomes intensive and sharp even at 290 K, indicating that the molecular
frame becomes rigid. The relation between the ENDOR spectra of these systems and the intramolecular dynamics is discussed. 相似文献
56.
Masaharu Murata Chifumi Gouda Kentaro Yano Shinichiro Kuroki Tatsuo Suzutani Yoshiki Katayama 《Analytical sciences》2003,19(10):1355-1357
In vitro screening assays are useful techniques for the determination of receptor-mediated activities in environmental samples. In order to define whether environmental chemicals act as an agonist or antagonist to the human estrogen receptor (hER), we have constructed a biosensor based on ligand-inducible interactions between hER and relative proteins on a quartz crystal microbalance (QCM). The his-tagged proteins, which were expressed in E. coli by recombinant DNA technology, were immobilized on an Au-electrode with Ni(II)-mediated chemisorption using the histidine tag and thiol-modified iminodiacetic acid. The resonance-frequency change of the protein-modified electrode was caused by association or dissociation with the hER relative proteins on the surface in the presence of estrogen. These results suggest that this sensor is applicable as a large-scale screening tool for estrogenic compounds. 相似文献
57.
High Intensity Discharge (HID) lamps are difficult to re-ignite rapidly because of the high pressure of metal vapor at high temperatures. We have succeeded in reducing the re-ignition time of high-pressure mercury lamps by using a pre-ionization step where an excess of electrons are generated by UV laser irradiation into the lamp. The effect of changing the laser focal point of the UV laser in the lamp and the position of an auxiliary electrode were also investigated. The time interval for re-ignition was reduced from 230s to 100s by laser irradiation near to the cathode. The results clearly showed that the effect of accelerating the re-ignition time by the pre-ionization step was determined by the behavior of excess electrons generated during the UV laser irradiation. 相似文献
58.
Shinsaku Dobashi Masaharu Kira Ryuichiro Tanaka Yoshinori Izawa Akihide Wada Michikazu Hara 《Analytical sciences》2006,22(4):603-606
The development of molecular spectroscopy has enabled us to select chlorinated aromatic hydrocarbons very rapidly. In particular, the laser ionization TOFMS (time-of-flight mass spectrometry) method is expected to be useful as an on-line, selective, and sensitive method. In the present work, real-time laser ionization TOFMS measurements were carried out on gaseous chlorinated aromatic hydrocarbons. The laser ionization method used resonance-enhanced two-photon ionization with the direct introduction of gas into the vacuum chamber. This method for analyzing aromatic hydrocarbons was developed using a pulsed supersonic molecular beam method. In the context of developing a highly selective and sensitive method, excitation of monochlorinated benzene at lambda = 263.07 nm was found to be effective in the wavelength region from 263 nm to 265 nm. Also the excitation of polychlorinated biphenyls at lambda = 266 nm was found to be substantially more effective than at lambda = 280, 300 or 320 nm. The achievable sensitivity for real-time (1 min) measurements using the laser ionization TOFMS technique was found to be in the ppbV range. 相似文献
59.
A network for motion detection of an approaching object without influence of the moving background was proposed based on the
insect visual system. The two-dimensional array of the analog complementary metal oxide semiconductor (CMOS) circuits for
extracting the edge signals of the approaching object without outputting those of the moving background was inserted at the
first stage of the network. At the next stage, analog CMOS circuits for detection of approaching velocity and direction, which
accept the extracted edge signals, were inserted based on the locust vision system. A chip of the proposed network was fabricated
with the 1.2 mm CMOS process. It was clarified from the measured results and the simulation results with the simulation program
with integrated circuit emphasis (SPICE) that the two-dimensional circuits of the first stage can only generate the signals
of target edges. The measured results showed that the chip can detect the approaching velocity and direction of the target
in the image which contains the moving background. 相似文献
60.