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321.
Spatially incoherent Fourier digital holography using a rotational shearing interferometer for four-step phase-shifting method is proposed. The previous incoherent Fourier holography using a rotational shearing interferometer [Watanabe and Nomura (Appl. Opt. 54:A18, 2015)] employs the two-step phase-shifting method in the vertical and horizontal polarizations. The reconstructed image contains a large bias term. This paper proposes introduction of two kinds of wave plates in one path of a rotational shearing interferometer for a four-step phase-shifting method. A Fourier hologram is obtained from the four recorded holograms for eliminating the bias term and the twin image. The numerical simulation and the optical experiment demonstrate improvement of the image quality of reconstructed image by the twin image and bias level reduction. Furthermore, the effect of the size of an image sensor on the image quality in rotational shearing interferometer is also investigated by the numerical simulations. 相似文献
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Hideki Katayanagi Bhim P. Kafle Takanori Mori Yasuhiro Takabayashi Yoshihiro Kubozono 《Journal of Quantitative Spectroscopy & Radiative Transfer》2008,109(9):1590-1598
The photoion yield spectra of an endohedral metallofullerene Pr@C82 were measured in the photon energy range of 100-150 eV by using time-of-flight mass spectrometry. Parent ions Pr@C82+, Pr@C822+ and Pr@C823+ were observed in the mass spectra. The photoion yield spectra of Pr@C822+ showed a broad peak at 120-140 eV that was assigned to the 4d-4f giant dipole resonance of the encapsulated Pr atoms. Absolute photoabsorption cross sections of Pr@C82 were evaluated from the photoion yield spectra to be 37±12 Mb at 110 eV (off-resonance) and 52±13 Mb at 130 eV (on-resonance). These cross sections of Pr@C82 were compared with the results of Ce@C82, the only metallofullerene whose photoionization properties have ever been studied near the 4d edge of the encapsulated metal atom. The enhancement of photoabsorption due to the giant resonance was found to be similar in Pr@C82 and Ce@C82, but there are marked differences in the peak shapes, which can be explained as due to interference effects between the fullerene cage and the encapsulated metal atoms. 相似文献
324.
Yasuyuki Matsushita Ayumi Suzuki Takuya Sekiguchi Kaori Saito Takanori Imai Kazuhiko Fukushima 《Applied Surface Science》2008,255(4):1022-1024
Cationic starch (CS) is routinely used in the papermaking process to improve the dry strength or printability of paper. The effectiveness depends on the distribution of the starch on the pulp fiber, and in this study, time-of-flight secondary ion mass spectrometry was used to investigate this distribution. The characteristic peak at 58m/z was applied to map the CS. Based on the imaging analysis of the handsheets with the CS as an internal additive, the distribution of CS became more uniform with decreasing freeness. The amount of adsorbed CS increased with increasing fiber length and was lower on vessels than on other fibers. These results were related to fibrillation. From the analysis of handsheets with CS as an external additive, the penetration depth of the starch into base paper increased with decreases in the sizing degree of the base paper. 相似文献
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Eiji Saito Atsushi Konno Kanji Yasui Tetsuo Endoh Maki Suemitsu 《Applied Surface Science》2008,254(19):6235-6237
Pyrometric interferometry has been observed during gas-source molecular beam epitaxy (GSMBE) of 3C-SiC on Si substrate using monomethyl silane. The period of the “temperature oscillation” is shown to correspond to λ/2n, with the λ and n being the wavelength used in the monochromatic optical pyrometry and the refractive index of the grown film, respectively. As is the case for other heteroepitaxies, pyrometric interferometry may provide a feasible real-time monitoring method for the growth of 3C-SiC film on Si substrates. 相似文献
326.
Jianzhong Zhang Yusheng Zhao George T. Gray III Wataru Utsumi Hattori Takanori 《Journal of Physics and Chemistry of Solids》2008,69(10):2559-2563
The phase transformations of titanium metal have been studied at temperatures and pressures up to 973 K and 8.7 GPa using synchrotron X-ray diffraction. The equilibrium phase boundary of the α-ω transition has a dT/dP slope of 345 K/GPa, and the transition pressure at room temperature is located at 5.7 GPa. The volume change across the α-ω transition is ΔV=0.197 cm3/mol, and the associated entropy change is ΔS=0.57 J/mol K. Except for ΔV, our results differ substantially from those of previous studies based on an equilibrium transition pressure of 2.0 GPa at room temperature. The α-ω-β triple point is estimated to be at 7.5 GPa and 913 K, which is comparable with previous results obtained from differential thermal analysis and resistometric measurements. An update, more accurate phase diagram is established for Ti metal based on the present observations and previous constraints on the α-β and ω-β phase boundaries. 相似文献
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