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81.
M. Kobayashi Y. Usuki M. Ishii M. Itoh M. Nikl 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2005,540(2-3):381-394
Since we presented our preliminary result (Nucl. Instr. and Meth. A 486 (2002) 170) at SCINT2001, we have continued our efforts to increase the light yield (LY) of PbWO4 scintillators by extending different dopings with an aim to find a possibility of using PbWO4 successfully in Positron Emission Tomography (PET). Overall result obtained for single doping as well as double and tripple co-dopings are summarized, including decay characteristics and radiation hardness. The LY in non-doped PbWO4 crystals with a size of 10×10×(20–30) mm3 is 25–35 photolectrons/MeV (phe/MeV) corresponding to 3–4% of the LY in BGO, when measured with a bialkali photomultiplier during a gate of 1 μs. The maximum LY increased to 49 phe/MeV for single doping with Mo6+, 80 phe/MeV for double co-doping of Mo6++Sb5+, and 85 phe/MeV for tripple co-doping of Mo6++Cd2++Sb5+. The radiation hardness is larger than 105 Gy for each of the samples co-doped with Mo6++Sb5+ and Mo6++Cd2++Sb5+, while it is much poorer in PWO:Mo6+. In each of these co-doped samples, a medium-speed green emission in the microsecond range is created besides the fundamental fast (a few nanoseconds range) blue one, giving a peak at 500 nm in the radioluminescence spectrum similarly as in PWO:Mo6+. 相似文献
82.
Y. Iwadate K. Fukushima Y. Seki K. Itoh T. Fukunaga M. Misawa H. Matsuura A. Kajinami N. Ohtori N. Umesaki H. Kofuji M. Myochin 《Science and Technology of Advanced Materials》2004,5(5-6):683
Although the melt structure of glass-forming ZnCl2 has so far been well studied, there exists quite little information on the structural change due to anion-substitution. In the present work, the short-range structure of ZnCl2–ZnBr2 mixture melts was analyzed systematically by time-of-flight pulsed neutron diffraction techniques, Raman spectroscopy, molecular orbital calculations, and molecular dynamics simulations. According to radial distribution analysis, it was found that there were tetrahedral structural units of ligand-substituted [ZnClnBr4−n]2− (n=0–4) in these melts, not implying the simple mixing of [ZnCl4]2− and [ZnBr4]2− units. Further detailed estimation indicated that the ligand-substituted complex anions were linked with each other by sharing a common anion. 相似文献
83.
We developed a dual-probe (DP) atomic force microscopy (AFM) system that has two independently controlled probes. The deflection of each cantilever is measured by the optical beam deflection (OBD) method. In order to keep a large space over the two probes for an objective lens with a large numerical aperture, we employed the OBD sensors with obliquely incident laser beams. In this paper, we describe the details of our developed DP-AFM system, including analysis of the sensitivity of the OBD sensor for detection of the cantilever deflection. We also describe a method to eliminate the crosstalk caused by the vertical translation of the cantilever. In addition, we demonstrate simultaneous topographic imaging of a test sample by the two probes and surface potential measurement on an α-sexithiophene (α-6T) thin film by one probe while electrical charges were injected by the other probe. 相似文献
84.
Kei Noda Ko Okamura Junko Taniguchi Masaru Suzuki Mitsunori Hieda 《Journal of Low Temperature Physics》2013,171(5-6):638-643
We have carried out quartz crystal microbalance (QCM) experiments for 4He films on an exfoliated single-crystalline graphite using a 32 kHz tuning fork, and have measured the temperature dependence of the resonance frequency and the Q value for various areal densities and oscillation amplitudes. Comparing with the previous experiments for Grafoil, the decoupling of the films due to the slippage or the superfluidity was larger than that of Grafoil, and the competition between the slippage and the superfluidity was observed in three-atom thick films. Furthermore, it was found that the slippage is suppressed gradually at higher temperature than the superfluid onset T c , and that the relaxation time decreases at low temperatures while it obeys the Arrhenius law at high temperatures. These results suggest a precursor to the superfluidity of 4He films. 相似文献
85.
Yasuhiro Itoh Takamasa Oshita Kohki Satoh Hidenori Itoh 《Electrical Engineering in Japan》2014,186(1):26-33
The decomposition characteristics of an artificial biogas, which is a mixture of CH 4, CO 2, and H 2 S, using a low‐pressure DC glow discharge have been investigated. It is found that H 2, CO, C 2 H 2, H 2 O, CS 2, and COS are produced from the artificial biogas in the glow discharge. About 65% of the hydrogen atoms in CH 4 are converted into H 2 at an input energy of 800 J, at which CH 4 is completely decomposed, and the decomposition characteristics of the artificial biogas are minimally dependent on the H 2 S additive. Further, H 2 S has a tendency to be decomposed earlier than the other components of the artificial biogas. When the glow discharge is generated in the artificial biogas with H 2 S, some of the carbon atoms are found to deposit on the electrodes and the wall of the discharge chamber. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 186(1): 26–33, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.22304 相似文献
86.
Today many people store music media files in personal computers or portable audio players, thanks to recent evolution of multimedia technologies. The more music media files these devices store, the messier it is to search for tunes that users want to listen to. We propose MusCat, a music browser to interactively search for the tunes according to features, not according to metadata (e.g. title, artist name). The technique firstly calculates features of tunes, and then hierarchically clusters the tunes according to the features. It then automatically generates abstract pictures, so that users can recognize characteristics of tunes more instantly and intuitionally. It finally visualizes the tunes by using abstract pictures. MusCat enables intuitive music selection with the zooming user interface. 相似文献
87.
88.
Takashi Goshima Yumi Isoda Madoka Sakaguchi Kenta Fukudome Kei Mizuta Susumu Nii 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(3):306-311
The biorefinery has been recognized as a new industry to produce both energy and chemical materials such as olefins and BTX from renewable resources. In this context the conversion of butyric acid over zeolites was investigated for establishing a new production route of propylene. Propylene was mainly generated by decarbonylation and dehydration of butyric acid. Our study proved that H-ZSM-5 (750) and silicalite were the best industrial catalyst among the tested ones. For H-ZSM-5 (750), the selectivity of propylene reached 64.2 C% and the ratio of the yield for propylene to theoretical yield (75 C%) became 85.6%. 相似文献
89.
90.
Ryo Mitsugi Tomoo Itoh Ryoichi Fujiwara 《International journal of molecular sciences》2015,16(7):14997-15008
The human DNAJB3 gene encodes a DNAJ (Heat shock protein 40; Hsp40) homolog, subfamily B, member 3 chaperone protein (DNAJB3), which can be down-regulated in disease conditions, as observed in decreased expression of DNAJB3 mRNA in peripheral blood mononuclear cells (PBMC) of obese patients. Recently, humanized UDP-glucuronosyltransferase (UGT) 1 mice (hUGT1 mice) were developed, in which the introduced human UGT1 gene contained a gene encoding human DNAJB3. In the present study, we analyzed the expression of human DNAJB3 mRNA in hUGT1 mice. Among the examined tissues, the testis had the highest expression of human DNAJB3 mRNA, while the lowest expression was observed in the liver. We found that the pattern of tissue-specific expression of mouse Dnajb3 in hUGT1 mice was very similar to that of human DNAJB3. We further demonstrated that the expression of human DNAJB3 in the liver was significantly reduced in high-fat-diet-fed hUGT1 mice compared to the expression level in the control mice, indicating that the expression of human DNAJB3 in hUGT1 mice could be similarly regulated in disease conditions such as obesity. Humanized UGT1 mice might therefore be useful to investigate the physiological role of human DNAJB3 in vivo. 相似文献