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991.
Ryo Masuda Takaya Mitsui Keiji Itoh Kouji Sakaki Hirotoshi Enoki Yumiko Nakamura Makoto Seto 《Hyperfine Interactions》2012,204(1-3):139-142
We have been developing a system for in situ M?ssbauer studies using synchrotron radiation (SR) to elucidate the mechanism of hydrogenation processes. In the system, samples reacts in a pressure-temperature chamber and SR-based M?ssbauer spectra using variable-frequency nuclear monochromator and energy spectra of inelastic nuclear resonant scattering (NRS) of SR are measured. As a feasibility study, the temperature dependence of the M?ssbauer and inelastic NRS spectra of 57Fe in c-GdFe2H3 under vacuum were measured. In both spectra, clear differences were observed between 373?K and 573?K. These differences can be interpreted by the change of microscopic environment around Fe at the dehydrogenation. Thus, it is confirmed that this system works well enough to perform the in-situ M?ssbauer study on the dehydrogenation of c-GdFe2H3. 相似文献
992.
The spectrum of modern illumination can be computationally tailored considering the visual effects of lighting. We investigated the spectral profiles of the white illumination maximizing the theoretical limits of the perceivable object colors. A large number of metamers with various degrees of smoothness were generated on and around the Planckian locus, and the volume in the CIELAB space of the optimal colors for each metamer was calculated. The optimal spectrum was found at the color temperature of around 5.7×10(3) K, had three peaks at both ends of the visible band and at around 510 nm, and was 25% better than daylight and 35% better than Thornton's prime color lamp. 相似文献
993.
Takahiro Hamada Eiji Fujii Dewei Chu Kazumi Kato Yoshitake Masuda 《Journal of Crystal Growth》2011,314(1):180-184
Morphological change from ZnO films to ZnO prisms is achieved by an electrochemical deposition method on a graphite substrate at the low temperature of 70 °C. The ZnO prisms, which are prism-shaped ZnO rods with a wide diameter, have hexagonal well-defined crystallographic facets. The ZnO prism is 1.4 μm in diameter and 1.3 μm in length. Transmission electron microscopy and electron diffraction patterns indicate that the ZnO prisms have a single-crystalline wurtzite structure with c-axis orientation. Additionally, cathodoluminescence shows that the annealed ZnO prisms in nitrogen gas emit a significant level of near-band-edge ultraviolet light. 相似文献
994.
Shiro Kubuki Hitomi Masuda Kazuhiko Akiyama Zoltán Homonnay Ernő Kuzmann Tetsuaki Nishida 《Hyperfine Interactions》2013,219(1-3):141-145
A relationship between electrical conductivity (σ) and local structure of 15Li2O·10Fe2O3·xSnO2·(70–x)V2O5·5P2O5 glass (x = 0–20 mol%), abbreviated as xLFSVP glass, was investigated by 57Fe- and 119Sn-Mössbauer spectroscopies, differential thermal analysis (DTA) and dc-four probe method. A small increase in quadrupole splitting (Δ) for FeIII was observed from 0.70 to 0.74± 0.02 mm s???1 with an increase of “x”, whereas isomer shift (Δ) values of 0.40±0.01 mm s???1 were independent of “x”. This result suggests that local distortion of FeIIIO4 tetrahedra was slightly increased in SnO2-containing vanadate glasses, which was reflected as an increase in glass transition temperature (Tg) from 266 to 285±5 °C. A slope of 675 K / (mm s???1) obtained in ‘Tg vs. Δ plot’ proved that FeIII occupied the site of network former (NWF). An isothermal annealing of 10LFSVP glass at 500 °C for 100 min resulted in a marked decrease of Δ from 0.72 to 0.56±0.02 mm s???1, indicating that local distortion of FeO4 tetrahedra was reduced by the structural relaxation of 3D-network. In contrast, identical δ and Δ values of 0.07±0.01 and 0.53±0.02 mms???1, respectively, were observed in 119Sn-Mössbauer spectra of 10LFSVP glass before and after the annealing. These results indicate that SnIVO6 octahedra are loosely bound in the glass matrix as a network modifier (NWM). A marked increase in σ from 7.4 × 10???7 to 9.1 × 10???3 S cm???1 was observed in 20LFSVP glass after the isothermal annealing, indicating that structural relaxation of 3D-network evidently causes a marked increase in σ. 相似文献
995.
In M-estimation under standard asymptotics, the weak convergence combined with the polynomial type large deviation estimate of the associated statistical random field Yoshida (2011) provides us with not only the asymptotic distribution of the associated M-estimator but also the convergence of its moments, the latter playing an important role in theoretical statistics. In this paper, we study the above program for statistical random fields of multiple and also possibly mixedrates type in the sense of Radchenko (2008) where the associated statistical random fields may be nondifferentiable and may fail to be locally asymptotically quadratic. Consequently, a very strong mode of convergence of a wide range of regularized M-estimators is ensured.Our results are applied to regularized estimation of an ergodic diffusion observed at high frequency. 相似文献
996.
We measure photoassociation rates in one-dimensional Bose gases, and so determine the local pair correlation function over a wide range of coupling strengths. As bosons become more strongly coupled, we observe a tenfold decrease in their wave function overlap, thus directly observing the fermionization of bosons. 相似文献
997.
Norihito Kijima Yuko Sakata Yasuhiko Takahashi Junji Akimoto Toshiya Kumagai Kaoru Igarashi Tadao Shimizu 《Solid State Ionics》2009,180(6-8):616-620
Single-phase specimens of α-MnO2 (hollandite-type) and β-MnO2 (rutile-type) were synthesized by the acid digestion of Mn2O3 under reflux conditions. The type of polymorph of MnO2 products was strongly dependent on the reaction temperature, type of acid used, and its concentration. The pH titration curve of α-MnO2 displayed a monobasic acid behavior toward Li+, but β-MnO2 showed a poor ion-exchange property. In contrast, both α-MnO2 and β-MnO2 acted as a rechargeable active material in a liquid organic electrolyte lithium cell. The initial discharge capacities of both electrodes exceeded 200 mAh/g (cut-off voltage: 2 V). After discharge–charge repetition, the α-MnO2 structure was still retained without structure collapse, although the β-MnO2 structure was destroyed. These findings show that Li+ ions can be inserted only into the hollandite-type tunnels in α-MnO2 and cannot diffuse the rutile-type linkages in α-MnO2 as well as those in β-MnO2 without structure collapse. 相似文献
998.
Mary A. Blanchette William Choy Jeffery T. Davis Amy P. Essenfeld Satoru Masamune William R. Roush Toshiya Sakai 《Tetrahedron letters》1984,25(21):2183-2186
A mild olefination procedure, utilizing LiCl and an amine, has been developed for use with base-sensitive aldehydes and phosphonates. 相似文献
999.
1000.
Inhibition of experimental pulmonary metastasis of Lewis lung carcinoma by orally administered beta-glucan in mice 总被引:2,自引:0,他引:2
I Suzuki T Sakurai K Hashimoto S Oikawa A Masuda M Ohsawa T Yadomae 《Chemical & pharmaceutical bulletin》1991,39(6):1606-1608
The inhibitory effect on experimental pulmonary metastasis of Lewis lung carcinoma (3LL) of SSG, a (1----3)-beta-D-glucan obtained from the fungus Sclerotinia sclerotiorum IFO 9395, administered orally was examined in mice. Oral administration of SSG for 10 consecutive days just after the intravenous implantation of tumor cells significantly inhibited the experimental pulmonary metastasis of 3LL at a dose of 2000 micrograms. However, SSG administered orally involving other timings was less effective. In comparison with oral administration, SSG was effective when administered intraperitoneally for 10 consecutive days at a dose of 200 micrograms. These results suggest that SSG given by both parenteral and nonparenteral routes is effective in the inhibition of experimental pulmonary metastasis of tumors. 相似文献