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51.
Shinya Takata Tomo Ogura Eiichi Ide Toshiaki Morita Akio Hirose 《Journal of Electronic Materials》2013,42(3):507-515
The effects of reducing solvents on the bonding process using silver oxide paste in a copper joint were investigated. Three solvent types were tested: diethylene glycol (DEG), triethylene glycol (TEG), and polyethylene glycol (PEG). The strength of the joints was assessed by fracturing, which occurred at the interface of the copper oxide layer and the copper substrate in DEG and TEG samples and at the bonded interface in the PEG sample. Analysis of the samples revealed that, in the DEG and TEG samples, the copper substrate was oxidized during the bonding process, which compromised the shear strength of the joints. In contrast, the PEG sample exhibited nonuniform sintering of the silver layer while retaining good shear strength. It was found that the combination of DEG and PEG produced optimum shear strength in the copper joint, as PEG suppressed the growth of copper oxide and DEG promoted the formation of a dense sintered silver layer. The bonding strength achieved was higher than that of the gold-to-gold joint made using standard Pb-5Sn solder. 相似文献
52.
Carbon monoxide has been selectively converted to methanol by means of an electrochemical photocell composed of the n-CdS photoanode and the Everitt's salt-modified platinum cathode. The catholyte was the CO-saturated aqueous solution containing a metal complex and a primary alcohol operating as homogeneous catalysts. In the anolyte, various reducing agents were added to reduce the holes created at the semiconductor. The current efficiency of the methanol formation was almost 100%, irrespective of the kind of metal complex if the reducing agent added as a hole scavenger to the anolyte has a sufficiently negative redox potential. 相似文献
53.
CdS/CuInSe2 (CIS) heterojunctions were investigated by XPS analysis. An In-excess layer which may form an ordered vacancy compound (OVC) was present at the as-deposited CIS surface and it remained after chemical bath deposition of a CdS layer. The In-excess layer was removed by preferential etching with NH3 aqueous solution. This result implies that the surface of the as-deposited CIS film was converted from the OVC with n-type conductivity into the CIS with p-type by NH3 treatment. The conduction band offsets at the CdS/p-CIS and CdS/n-OVC were determined to be 1.0 and 0.3 eV, respectively. The CIS solar cells fabricated with n-OVC surface layer exhibited higher cell efficiencies than those fabricated with p-CIS surface layer. 相似文献
54.
S. Kodaira N. Yasuda K. Ogura N. Hasebe 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(10):1817-1822
We experimentally determined the suitable conditions of temperature and air pressure for measuring charge and mass compositions of heavy cosmic rays using CR-39 track detectors during long-duration, high-altitude balloon flights. The experiments were carried out utilizing Fe ion beams from Heavy Ion Medical Accelerator (HIMAC). Changes in the track registration sensitivity with temperature were studied at temperatures between 213 and 293 K. The charge and mass shifts around Fe ions are possibly 0.11 cu (charge unit) and 0.47 amu (atomic mass unit) at the temperature deviation between 227 and 243 K at balloon altitude. Decrease in track registration sensitivity as air pressure decreases has been observed between 13 Pa and 27 kPa. The charge and mass shifts around Fe ions are inferred to be 0.02 cu and 0.09 amu, respectively, when pressure varies between 20 and 27 kPa. During balloon flight, air pressure drops below this; therefore, care must be taken to keep the temperature and air pressure of CR-39 detectors within acceptable limits. 相似文献
55.
T Shimizu I Narabayashi Y Ogura Y Uesugi K Tabuchi R Namba Y Nakata R Matsui K Sueyoshi T Kawai 《Canadian Metallurgical Quarterly》1995,13(3):109-113
The purpose of this study was to evaluate the clinical usefulness of three-dimensional (3D) images of the bronchi obtained using helical CT. Thirteen patients with lung cancer, one with tracheal diverticulum, and one with bronchial amyloidosis were examined. The CT scanner employed was the Toshiba Xforce. The helical CT scan cycle consisted of 20 continuous rotations, each requiring 1.5 sec, for a total scanning time of 30 sec. Scans were obtained using a 5-mm X-ray beam width, a 5-mm/1.5 sec couchtop sliding speed, and a 2-mm reconstruction interval. 3D images were reconstructed using a CEMAX VIPstation. The optimal lower and upper threshold CT values for 3D images of the bronchi were -650 and -100 HU, respectively, and 3D images clearly depicted endobronchial lesions. Cartilage crescents were also demonstrated, but longitudinal and circular mucosal folds could not be visualized. In conclusion, 3D images of the bronchi acquired using helical CT were useful in evaluating endobronchial lesions. 相似文献
56.
Masaru Ogura Susumu Kage Masayoshi Hayashi Masahiko Matsukata Eiichi Kikuchi 《Applied catalysis. B, Environmental》2000,27(4):L213-L216
Effect of second components on the catalytic performance of Pd/H-ZSM-5 zeolite (Pd: 0.4 wt.%) was evaluated by a durability test of NO reduction with CH4 at a relatively high temperature of 500°C in the presence of water vapor for a prolonged period. The Pd/H-ZSM-5 showed high stable activity for this reaction without H2O in the reactant feed, while immediate and irreversible deactivation was observed in the presence of H2O, resulting in no activity after 7 h. The second components such as Co, Rh, Ag, Ce, and Fe introduced individually to the Pd/H-ZSM-5 enhanced the durability, and in particular the addition of 3.3 wt.% Co led to a stable NO conversion for more than 40 h in the presence of H2O. 相似文献
57.
Yoshinori Kawamura Kentaro Ochiai Tsuyoshi Hoshino Keitaro Kondo Yasunori Iwai Kazuhiro Kobayashi Masaru Nakamichi Chikara Konno Toshihiko Yamanishi Takumi Hayashi Masato Akiba 《Fusion Engineering and Design》2012,87(7-8):1253-1257
In a fusion reactor, the prediction of tritium release behavior from breeder blanket is important to design the tritium recovery system, but the amount of tritium generated is necessary information to do that. Hence, tritium generation and recovery studies on lithium ceramics packed bed have been started by using fusion neutron source (FNS) in Japan Atomic Energy Agency (JAEA). Lithium titanate (Li2TiO3) was selected as tritium breeding material, and its packed bed was enclosed by the beryllium blocks, and was kept at certain temperature during fusion neutron irradiation. During irradiation, the packed bed was purged with the sweep gas continuously, and tritium released was trapped in each gas absorber selectively by chemical form. In this work, the effect of sweep gas species on tritium release behavior was investigated. In the case of sweep by helium with 1% of hydrogen, tritium in water form was released sensitively corresponding to the irradiation. This is due to existence of the water vapor in the sweep gas. On the other hand, in the case of sweep by helium without water vapor, tritium in gaseous form was released first, and release of tritium in water form was delayed from gaseous tritium and was gradually increased. 相似文献
58.
Shiplu Roy Chowdhury Yuichi Muneyuki Yasunori Takezawa Masahiro Kino-oka Atsuhiro Saito Yoshiki Sawa Masahito Taya 《Journal of Bioscience and Bioengineering》2010,109(3):310-313
The transitional behaviors of myoblasts toward differentiation were investigated in the cultures at the low and high seeding densities (respectively, X0 = 1.0 × 103 and 2.0 × 105 cells/cm2). In the culture at the low seeding density, an increase in confluence degree accompanied a decrease in growth potential (Rp), being Rp = 0.85 and 0.11 at t = 48 and 672 h, respectively. Myoblasts seeded at the high density resulted in the immediate cessation of growth with keeping the low range of Rp = 0.02–0.09 throughout the culture. The reduction of Rp led to the generation of three subpopulations of cells in proliferative, quiescent and differentiated states. Close cell contacts in the confluent state of high seeding culture induced cell quiescence to a higher extent with suppressing differentiation. 相似文献
59.
Kenichi Kikuchi Yasunori Fujii 《Journal of Infrared, Millimeter and Terahertz Waves》2010,31(10):1205-1211
Performances of 640-GHz Superconductor–Insulator–Superconductor (SIS) mixers developed for the Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) mission are described. SMILES, launched in September 2009, is the first mission to observe atmosphere from space using superconducting mixers. Ground test performances of the SIS mixers show very flat gain and noise characteristics in their observation bands in compliance with the specifications required for SMILES. 相似文献
60.
Nobuaki Nishimura Ryuichi Ogura Satoshi Matsumoto Maya Mizuno Kaori Fukunaga 《Electrical Engineering in Japan》2013,183(1):9-15
The stock of aged power equipment is increasing and it is important to clarify the characteristics of deteriorated insulating oil. This paper describes a basic study of molecular behavior in the oxidation of insulating oil by terahertz spectroscopy. The oxidation of insulating oil was modeled by using various compositions of dodecane and 2‐octanol. The terahertz measurements indicated that signi?cant absorption related to hydroxyl groups (‐OH) occurred between 6 and 7 THz. The absorption band was also observed in accelerated aging alkylbenzene, which is used in power equipment as insulating oil and is sensitive to hydrogen bonds. © 2013 Wiley Periodicals, Inc. Electr Eng Jpn, 183(1): 9–15, 2013; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.22335 相似文献