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41.
Hirotaka Ogawa Akinori Kan Norihiro Ikeda Akihiro Fujita 《Physica B: Condensed Matter》2012,407(21):4308-4312
The effect of In doping on the electroluminescence (EL) properties of Zn2SiO4:In thin films was investigated. In-doped Zn2SiO4 thin films were deposited on BaTiO3 substrates and their EL properties were characterized in this study. X-ray powder diffraction patterns of In-doped Zn2SiO4 powders revealed a single phase of Zn2SiO4 for In concentrations up to approximately 1.5 mol%, whereas a secondary phase of In2O3 was observed for In concentrations in the range of 2–10 mol%. The maximum luminance of thin film electroluminescent (TFEL) devices varied significantly with the amount of In doping. The highest luminance with blue emission was obtained when 2 mol% In was doped. The blue emission of In-doped Zn2SiO4 thin film may be related to the In substitution for Zn. The 2 mol% In-doped Zn2SiO4 thin film exhibited blue emission with CIE color coordinates of x=0.208 and y=0.086. 相似文献
42.
We developed a continuous-spectrum light beam from Compton backscattering by using coherent synchrotron radiation in an L-band linac at the Kyoto University Research Reactor Institute. The ratio of Compton backscattered photons to background photons when coherent synchrotron radiation was used was three times larger than when coherent transition radiation was used. The transmission spectrum of a polystyrene film in the terahertz-wave region was evaluated by measuring the spectrum of the Compton backscattered photons and it roughly agreed with that measured by a Martin–Puplett-type interferometer. The spectrophotometry using Compton backscattering shows promise as a new tool for investigations in terahertz-wave science. 相似文献
43.
Yusuke Iwasaki Masato Goto Keisuke Mochizuki Emi Terayama Rie Ito Koichi Saito Norihiro Sugino Tsunehisa Makino Hiroyuki Nakazawa 《Biomedical chromatography : BMC》2011,25(4):503-510
A selective and sensitive HILIC‐MS/MS method for the simultaneous quantification of nicotine and its metabolites in human maternal and cord sera was developed and validated. After solid‐phase extraction, LC separation was achieved on a hydrophilic interaction chromatography. The validated method is capable of selective identification as well as accurate and sensitive quantification. Analyte recovery ranged from 86.2 to 107.7% and intra‐ and inter‐day assay precision were less than 15% relative standard deviation. This sensitive HILIC‐MS/MS method can be used to determine nicotine and its metabolic profile in smokers. This validated method is useful for the determination of nicotine and its metabolites in human serum in future studies of the effects of nicotine exposure on neonatal outcome. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Mechanical Characterization Measurement of Polymer Material under Stress by Birefringence Microscope
Some polymer materials under tensile stress provide us interesting information. Internal structure changes of polymer materials
must be observed by external stress. Birefringence shows the orientation characteristic in molecular orientation. A microscopic
measurement system for birefringence distribution is proposed to analyze the relation between applied stress and birefringence
distribution of an internal structure. Birefringence distributions of gelatin such as phase difference and azimuthal angle
are shown in cases of loading and unloading stress as a demonstration. The phase difference increased nonlinearly with each
process, and change of birefringence in the elastic domain was different from that in the plastic domain. 相似文献
46.
Norihiro Fukuchi Ye Biqing Yasunori Igasaki Narihiro Yoshida Yuji Kobayashi Tsutomu Hara 《Optical Review》2005,12(5):372-377
We have developed optically-addressed and electrically-addressed liquid crystal spatial phase-only light modulators having
no pixelized structures. We obtained a large depth of phase-only modulation and high diffraction efficiency based on the electro-optical
characteristics of a parallel-aligned nematic liquid crystal. These spatial light modulators (SLM) are of the reflection type,
so there would be a loss of power in the readout light from the half mirror, which was set up so as to separate the incident
and reflected lights. To optimize the characteristics of a reflection type spatial phase-only light modulator, we have proposed
an oblique incident optical readout setup. We have examined the effect of conditions such as the polarization direction and
the incidence angle of the readout light, and the orientation of liquid crystal molecules in the SLM. High diffraction efficiency
close to the theoretical maximum value was obtained by adjusting the above conditions. The simulation analysis can well explain
the experimental results of phase modulation. 相似文献
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Periodic mesoporous organosilicas (PMOs) prepared by surfactant-directed polycondensation of bridged organosilane precursors are promising for a variety of next-generation functional materials, because their large surface areas, well-defined nanoporous structures and the structural diversity of organosilica frameworks are advantageous for functionalization. This critical review highlights the unique structural features of PMOs and their expanding potential applications. Since the early reports of PMOs in 1999, various synthetic approaches, including the selection of hydrolytic reaction conditions, development of new precursor compounds, design of templates and the use of co-condensation or grafting techniques, have enabled the hierarchical structural control of PMOs from molecular- and meso-scale structures to macroscopic morphology. The introduction of functional organic units, such as highly fluorescent π-conjugates and electroactive species, into the PMO framework has opened a new path for the development of fluorescent systems, sensors, charge-transporting materials and solid-state catalysts. Moreover, a combinational materials design approach to the organosilica frameworks, pore wall surfaces and internal parts of mesopores has led to novel luminescent and photocatalytic systems. Their advanced functions have been realized by energy and electron transfer from framework organics to guest molecules or catalytic centers. PMOs, in which the precise design of hierarchical structures and construction of multi-component systems are practicable, have a significant future in a new field of functional materials (93 references). 相似文献
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