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71.
M Sekiyama W Hirano Y Watanabe Y Miura T Kawaguchi 《Canadian Metallurgical Quarterly》1996,43(11):965-973
Japanese law provides for regular medical examinations for the aged. A simulation study to determine the relationship between medical expenditures of cardiovascular disease patients and government-sponsored health check-ups for the aged was conducted in a small community town in Kanagawa Prefecture. The results showed that medical expenditures decreased in accordance with an increase in health screening. However, medical expenditure for out-patients increased slightly with an increase in screening for those cardiovascular disease patients who had not received treatment prior to the government health checkup. 相似文献
72.
Masayuki Nagai Satoru Fujitsu Takafumi Kanazawa Hiroaki Yanagida 《Journal of Materials Science》1981,16(6):1633-1642
Two series of solid solutions, Na
x
Ca(1−x)/2Zr2(PO4)3 (NCZP(x), 0⩽x⩽1) and Na
x
Nb1-x
Zr1+x
(PO4)3(NNZP(x), 0⩽x⩽1), were synthesized. They were examined by powder X-ray diffraction, infra-red (i.r.) absorption and Raman scattering.
Ionic conductivities of graphite coated samples were measured. A complete series of solid solutions was formed for NCZP(x), while a second phase was found forx<0.1 for NNZP(x). The i.r. and Raman spectra of their solid solutions consistently showed the formation of PO4 tetrahedra with different geometries. The composition dependence of conductivity is interpreted on the basis of a structural
change around Na+. 相似文献
73.
Takafumi Ishii Takuya Maie Naofumi Kimura Yuki Kobori Yasuo Imashiro Jun-ichi Ozaki 《International Journal of Hydrogen Energy》2017,42(23):15489-15496
The use of carbon cathode catalysts in polymer electrolyte fuel cells instead of the current platinum catalysts is attracting increasing attention. We claim that two factors are important for enhancing the activity of carbon cathode catalysts in the oxygen reduction reaction (ORR): the formation of a nanoshell structure and co-doping with boron and nitrogen. Herein, we investigate the preparation and characterization of active ORR carbon catalysts that combine the above factors. Boron and nitrogen (BN)-doped nanoshell-containing carbon (BN-NSCC) was prepared by carbonizing a mixture of poly(furfuryl alcohol), cobalt phthalocyanine, melamine, and a trifluoroborane–methanol complex at 1000 °C. Transmission electron microscopy and X-ray photoelectron spectroscopy revealed the formation of nanoshell structures with distorted graphitic layers and the introduction of boron and nitrogen atoms, respectively. The ORR activity was evaluated in oxygen-saturated 0.5 mol dm?3 H2SO4 using Koutecky–Levich analysis. The BN-NSCC showed an eight to ten times higher ORR activity than undoped NSCC, with an increased number of electrons participating in the reaction. Tafel analysis revealed a change in the rate-determining step caused by BN-doping. Thus, the combination of a nanoshell structure and co-doping with boron and nitrogen was found to improve the ORR activity of carbon catalysts. 相似文献
74.
A formulation for calculating the optical second-harmonic power based on the Cerenkov-radiation-type phase matching is derived for a crystal-cored fiber. The prerequisite condition for high efficiency is expressed by a simple relation by use of the refractive indices of a core crystal, a core radius, and a fundamental wavelength. An organic crystal-cored fiber is designed and practically fabricated by the guiding principle derived here. A blue second-harmonic wave of 1.4 mW is obtained from a 1-mm-long fiber by use of a 60-mW semiconductor laser, and the second-harmonic intensity agrees well with the prediction. Degradation of the organic core crystal caused by the generated blue wave is observed, and the lifetime of the device is evaluated. 相似文献
75.
Kenji Kanamori Tohru Kineri Ryohei Fukuda Takafumi Kawano Keishi Nishio 《Journal of Materials Science》2009,44(3):855-860
Amorphous ZrW2O8 powder and amorphous SiO2 powder were prepared by a sol–gel process as raw materials, and high-density ZrW2O8–SiO2 were successfully prepared at a much lower temperature of 923 K for a much shorter holding time of 10 min by spark plasma
sintering (SPS) method rather than by conventional melt-quenching method. The relative densities of 0.85ZrW2O8–0.15SiO2 and 0.70ZrW2O8–0.30SiO2 were 99.4% and 96.6%, respectively. The combined technique of a sol–gel process and SPS should enable us to prepare the varied
types of high-density composites of ZrW2O8 without severe thermal cracking caused by melt-quenching. The thermal expansion properties and dielectric properties of ZrW2O8–SiO2 were also investigated. 相似文献
76.
Koji Nakano Motonobu Takahashi Keiko Kawaguchi Kyoko Nozaki 《Synthetic Metals》2009,159(9-10):939-942
New π-conjugated polymers with dibenzo[d,d′]benzo[1,2-b:4,5-b′]difuran (DBBDF) unit in the main chains were synthesized. Copolymerization of 6,12-diiodo-DBBDF with p-diethynylbenzene or 2,7-diethynylfluorene derivative under Sonogashira–Hagiwara coupling-reaction condition gave the corresponding copolymer. The resulting copolymers were soluble in organic solvents such as tetrahydrofuran and chloroform. In UV–vis absorption spectra, both copolymers showed red-shifted spectra compared to their monomer units. In the chloroform solutions, the copolymer with DBBDF and p-diethynylbenzene units showed yellowish-green emission, while the copolymer with DBBDF and 2,7-diethynylfluorene units did greenish-blue emission. 相似文献
77.
H Saeki H Kuwano H Kawaguchi K Sonoda T Ohga K Kitamura H Nakashima Y Toh K Sugimachi T Oiwa 《Canadian Metallurgical Quarterly》1998,28(12):1254-1256
A Japanese man, who had undergone a subtotal esophagectomy reconstructed with a gastric tube through an antesternal route for esophageal carcinoma 16 years previously, was admitted to our hospital because of an abdominal incisional hernia. The abdominal incisional hernia was in his upper abdomen and was difficult to push back into the intraabdominal cavity by hand. The hernia was successfully repaired by operation. We thus conclude that an abdominal incisional hernia is a rare but important late-phase complication occurring after an esophagectomy reconstructed with either an antesternal or retrosternal route, and an operation should be the treatment of choice. 相似文献
78.
Y. Kobayashi S. Yamazaki Y. Kurokawa T. Miyakawa H. Kawaguchi 《Journal of Materials Science: Materials in Electronics》1992,3(1):20-25
We have examined the preparation of transparent alumina film and CdS-doped alumina film prepared by the sol-gel process using aqueous sol starting from AlCl3. The resulting alumina films obtained by sol-gel transformation are transparent in the visible and near infrared up to 1000 °C. Homogeneous solution of alumina sol and Cd(CH3COO)2 was converted into gel film by dehydration. Then, on exposure to H2S stream at 250–600 °C, a CdS-doped film was obtained. It shows relatively sharp blue-shifted visible absorption that is attributed to size quantization effect. Large nonlinear absorption and refractive index have been obtained, because high concentration of CdS particles can be achieved by using this method. 相似文献
79.
Tomoyuki Kawaguchi Yasuhiro Rachi Wataru Sugimoto Yasushi Murakami Yoshio Takasu 《Journal of Applied Electrochemistry》2006,36(10):1117-1125
Highly dispersed ternary PtRuRh/C anode catalysts for direct methanol fuel cells were prepared with various contents and their electro-catalytic activities towards methanol oxidation at 25 °C and 60 °C were examined to investigate the influence of the catalyst composition. Electrocatalysts were prepared by a co-impregnation method using ethanolic solutions of metal precursors and carbon black followed by pyrolysis under reducing conditions. X-ray diffraction analysis revealed that the fcc peaks shifted to higher diffraction angles with increasing Rh content, indicating the alloying of Rh into the fcc structure. In terms of the mass specific current density, the activity towards methanol oxidation differed significantly depending on the catalysts composition and cell temperature. The catalyst prepared at a ratio of Pt:Ru:Rh = 1:1:2 exhibited the highest activity at 60 °C of 155 A (g-Pt)−1 at 0.5 V vs. RHE. 相似文献
80.
Toshinori Okura Giichi Sudoh Hiroyuki Inoue Takafumi Kanazawa 《Journal of Materials Science》1995,30(4):1033-1036
The SiKΒ X-ray emission spectra for several silicates and silico-phosphates were measured using a high-resolution X-ray fluorescence spectrometer with two InSb(III) analyser crystals. Molecular orbital calculation analysis for the obtained spectra was performed by a SCC-DV-Xα method and the energy positions and relative intensities of the spectral fine structures were calculated with Slater's transition-state method. The calculated results interpreted the spectral profiles successfully. The energy shifts of the SiKΒ main peak were also discussed in terms of the electronegativity of the second-nearest-neighbour atoms. These shifts were attributed to the changes in the stability of the Si-O bonds due to the existence of second-nearest-neighbour P atoms. 相似文献