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151.
H. Yamane K. Kanai Y. Ouchi N. Ueno K. Seki 《Journal of Electron Spectroscopy and Related Phenomena》2009,174(1-3):28
We present the electronic structure of various pentacene thin films grown on Au(1 1 1), Cu(1 1 1), Cu(1 0 0), and Cu(1 1 0) surfaces studied by angle-resolved ultraviolet photoemission spectroscopy using synchrotron radiation. A systematic variation of the metal surface such as the substrate metal and its surface symmetry allows a comprehensive discussion on the correlation between the electronic structure and the interface geometric structure. In the monolayer regime, we observed the evidence of the formation of the organic–metal interface state depending on the metal surface, i.e., the interface geometric structure. This evidence is explained by the different organic–metal and intermolecular interactions, which originate from the hybridization of the molecular orbitals with the metal wavefunction. These interface geometric and electronic phenomena can be a seed for the subsequent film growth and resultant films electronic structure. 相似文献
152.
Tetsuya Kawano Haruhiko Morito Takahiro Yamada Takeyoshi Onuma Shigefusa F. Chichibu Hisanori Yamane 《Journal of solid state chemistry》2009,182(8):2004-2009
Single crystals of iron(II) pyroborate, Fe2B2O5, were prepared at 1000–1050 °C under an argon atmosphere. The crystals were transparent, yellowish in color and needle-like or columnar. The crystal structure of Fe2B2O5 was analyzed by single-crystal X-ray diffraction. Refined triclinic unit cell parameters were a=3.2388(2), b=6.1684(5), c=9.3866(8) Å, α=104.613(3)°, β=90.799(2)° and γ=91.731(2)°. The final reliability factors of refinement were R1=0.020 and wR2=0.059 [I > 2σ(I)]. Transmittance over 50% in the visible light region from 500 to 750 nm was observed for a single crystal of Fe2B2O5 with a thickness of about 0.3 mm. The light absorption edge estimated from a diffuse reflectance spectrum was at around 350 nm (3.6 eV). Magnetic susceptibility was measured for single crystals at 4–300 K. Fe2B2O5 showed antiferromagnetic behavior below the Néel temperature, TN≈70 K, and the Weiss temperature was TW=36 K. The effective magnetic moment of Fe was 5.3μB. 相似文献
153.
Hisanori Yamane Ryota Yagi Akira Hosono Yuji Masubuchi 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(6):702-706
A new quaternary oxide, BiGaTi4O11 (bismuth gallium tetratitanium undecaoxide), was prepared by heating a mixture of the binary oxides at 1373 K in air. BiGaTi4O11 melts at 1487 K and prismatic single crystals were obtained from a sample melted at 1523 K and solidified by furnace cooling. The structure of BiGaTi4O11 was analyzed using single‐crystal X‐ray diffraction to be of a new type that crystallized in the space group Cmcm. A Bi3+ site is coordinated by nine O2? anions, and three oxygen‐coordinated octahedral sites are statistically occupied by Ga3+ and Ti4+ cations. A relative dielectric constant of 46 with a temperature coefficient of 57 ppm K?1 in the temperature range 297–448 K was measured for a polycrystalline ceramic sample at 150 Hz–1 MHz with a dielectric loss tan δ of less than 0.01. Electrical resistivities measured at 1073 K by alternating‐current impedance spectroscopic and direct‐current methods were 1.16 × 10?4 and 1.14 × 10?4 S cm?1, respectively, which indicates that electrons and/or holes were conduction carriers at high temperature. The optical band gap estimated by the results of diffuse reflectance analysis was 2.9–3.0 eV, while the band gap obtained from the activation energy for electrical conduction was 3.5 eV. 相似文献
154.
Fe–Pt–MgO stacked storage layer constructed by [Fe–Pt/Fe–Pt–MgO/Fe–Pt] trilayered structure was proposed for a next-generation high-density perpendicular magnetic recording medium. The Fe–Pt–MgO composite middle layer was prepared by sputtering the Fe–Pt–MgO composite-type target including relatively large MgO content of 50 vol%. The Fe–Pt(0 0 1) seed layer deposited on MgO underlayer was effective in forming the ordered fct(0 0 1) phase for the Fe–Pt–MgO composite film. The reduction of transition jitter noise and the suppression of signal overlap were observed in the stacked-type medium with the Fe–Pt–MgO middle layer of 1 nm thickness. The improvement of recording properties is attributed to the pinning effect of magnetic domain wall by the Fe–Pt–MgO composite layer inserted into the middle of pure Fe–Pt storage layer. 相似文献
155.
156.
T Yamane T Hashizume K Yamashita K Hosoe T Hidaka K Watanabe H Kawaharada S Kudoh 《Chemical & pharmaceutical bulletin》1992,40(10):2707-2711
Benzoxazinorifamycin reacted with various secondary amines to yield various 5'-substituted aminobenzoxazinorifamycin derivatives. The derivatives exhibited potent activities against gram-positive bacteria and mycobacteria. The antimicrobial activities of these compounds against Mycobacterium tuberculosis and Mycobacterium intracellulare were superior to those of rifampicin. Some of these compounds showed good plasma levels after oral administration in rats. 相似文献
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160.
Masayuki Yamane Hiroshi Kawazoe Atsuo Yasumori Toshikazu Takahashi 《Journal of Non》1988,100(1-3):506-510
A glass rod of the PbO---K2O---B2O3---SiO2 system having a radial gradient of refractive index has been prepared by the sol-gel process using aqueous solutions of lead acetate and potassium nitrate as the sources for index-modifying cations. A gel prepared by gelatinizing a sol from the mixture of tetramethoxysilane, tetraethoxysilane, and the aqueous solutions of boric acid and lead acetate was placed in an aqueous solution of potassium nitrate to form the concentration gradient of modifier cations by diffusion through the micropores of the gel. The glass rod of about 7 mm in diameter obtained by drying and sintering the gel had a refractive index of parabolic profile changing from the center toward the perimeter with a maximum difference of about 0.04. 相似文献