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排序方式: 共有883条查询结果,搜索用时 109 毫秒
141.
Takayuki Yanagida Kentaro FukudaYutaka Fujimoto Noriaki Kawaguchi Shunsuke KurosawaAtsushi Yamazaki Kenichi WatanabeYoshisuke Futami Yuui YokotaJan Pejchal Akira Yoshikawa Akira UritaniTetsuo Iguchi 《Optical Materials》2012,34(5):868-871
Eu2+ 0.05%, 0.1%, and 0.2% activated LiF-SrF2 eutectic scintillators were prepared by the Bridgman method using 6Li enriched (95%) raw material. The α-ray-induced radio luminescence spectra showed intense emission peak at 430 nm due to an emission from Eu2+ 5d-4f transition in the Eu:SrF2 layers. When excited by 252Cf neutrons, all the samples exhibited almost the same light yields of 5000-7000 ph/n with a typical decay times of several hundreds ns. 相似文献
142.
Shingo Wakahara Yuki FuruyaTakayuki Yanagida Yuui YokotaJan Pejchal Makoto SugiyamaNoriaki Kawaguchi Daisuke Totsuka Akira Yoshikawa 《Optical Materials》2012,34(4):729-732
0.1%, 0.5%, 1% and 3% Ce doped scintillation crystals based on NaF-CaF2-LuF3 solid solutions were grown from the melt using Micro-Pulling-Down (μ-PD) method. The grown crystals were transparent and their transmittance was approximately 80% for the wavelengths longer than 320 nm. Concerning the scintillation properties, radio-luminescence peaks of the crystals were detected at approximately 330 nm. The light yield of the crystals was also measured using γ-ray (137Cs and 22Na) as the excitation source. 相似文献
143.
Dohiko Terada Hisatoshi Kobayashi Kun Zhang Ashutosh Tiwari Chiaki Yoshikawa Nobutaka Hanagata 《Science and Technology of Advanced Materials》2012,13(1)
The processing of a polyelectrolyte (whose functionality is derived from its ionized functional groups) into a nanofiber may improve its functionality and yield multiple functionalities. However, the electrospinning of nanofibers from polyelectrolytes is imperfect because polyelectrolytes differ considerably from neutral polymers in their rheological properties. In our study, we attempt to solve this problem by applying a voltage of opposite polarity to charges on a polyelectrolyte. The application of this ‘countervoltage’ can temporarily mask or screen a specific rheological property of the polyelectrolyte, making it behave as a neutral polymer. This approach can significantly contribute to the development of new functional nanofiber materials. 相似文献
144.
Herman Jacobus Cornelis Voorwald Mauro Pedro Peres Midori Yoshikawa Pitanga Costa Maria Odila Hilário Cioffi 《Journal of Materials Science》2010,45(22):6094-6100
In spite of toxicity, hydrogen embrittlement susceptibility, and environmental issues, cadmium electroplating is usually applied
on high strength AISI 4340 aeronautical steel due to its efficient protection against electrochemical corrosion. Ion vapor
deposition (IVD) process with pure aluminum also offers good protection against corrosion with the advantages of decreasing
hydrogen embrittlement susceptibility and improving the fatigue strength of metallic components. In this research, the effects
of aluminum electroplating and IVD aluminum coating on the rotating bending fatigue strength of AISI 4340 steel were evaluated
in comparison with cadmium electroplated specimens. Experimental fatigue results showed that both aluminum electroplating
and IVD aluminum coatings are possible alternatives to cadmium electroplating. 相似文献
145.
Guoqiang Xie Song Li D.V. Louzguine-Luzgin Ziping Cao Noboru Yoshikawa Motoyasu Sato Akihisa Inoue 《Metallurgical and Materials Transactions A》2010,41(7):1714-1719
Using a gas-atomized Ni59.35Nb34.45Sn6.2 metallic glassy alloy powder blended with Sn powder of various contents, Ni-Nb-Sn bulk metallic glassy matrix composites
were fabricated by a microwave (MW)–induced sintering process in a single-mode 2.45 GHz MW applicator in a separated magnetic
field. The Ni59.35Nb34.45Sn6.2 glassy alloy powder and its mixed powders containing Sn particles could be heated well in the magnetic field. The addition
of Sn particles promoted densification of the sintered Ni59.35Nb34.45Sn6.2 metallic glassy powder. Bulk samples without crystallization of the glassy matrix and with good bonding state among the particles
were achieved at a sintering temperature of 833 K. 相似文献
146.
Chuangchote S Fujita M Sagawa T Sakaguchi H Yoshikawa S 《ACS applied materials & interfaces》2010,2(11):2995-2997
We propose new strategy to facilitate the fabrication of conjugated polymer fiber with higher oriented structures, which focused on electrospinning of a blend solution of regioregular poly(3-hexylthiophene) (rr-P3HT) and poly(vinyl pyrrolidone) (PVP). SEM observation revealed that the blend system forms homogeneous composite nanofibers. This system exhibits the specific feature of strong interchain contribution of P3HT from UV-vis absorption, fluorescence spectroscopic, XRD, and photoelectron spectrometric (for HOMO levels) investigations. We also demonstrate the removal of the PVP component from the P3HT/PVP composite fibers through the selective extraction and such strong interchain stacking of pristine P3HT fiber mat can be remarkably maintained. 相似文献
147.
Mikio Enoeda Hisashi Tanigawa Takanori Hirose Satoshi Suzuki Kentaro Ochiai Chikara Konno Yoshinori Kawamura Toshihiko Yamanishi Tsuyoshi Hoshino Masaru Nakamichi Hiroyasu Tanigawa Koichiro Ezato Yohji Seki Akira Yoshikawa Daigo Tsuru Masato Akiba 《Fusion Engineering and Design》2012,87(7-8):1363-1369
The development of a Water Cooled Ceramic Breeder (WCCB) Test Blanket Module (TBM) is being performed as one of the most important steps toward DEMO blanket in Japan. For the TBM testing and evaluation toward DEMO blanket, the module fabrication technology development by a candidate structural material, reduced activation martensitic/ferritic steel, F82H, is one of the most critical items from the viewpoint of realization of TBM testing in ITER. In Japan, fabrication of a real scale first wall, side walls, a breeder pebble bed box and assembling of the first wall and side walls have succeeded. Recently, the real scale partial mockup of the back wall was fabricated. The fabrication procedure of the back wall, whose thickness is up to 90 mm, was confirmed toward the fabrication of the real scale back wall by F82H. Important key technologies are almost clarified for the fabrication of the real scale TBM module mockup. From the view point of testing and evaluation, development of the technology of the blanket tritium recovery, development of advanced breeder and multiplier pebbles and the development of the blanket neutronics measurement technology are also performed. Also, tritium production and recovery test using D-T neutron in the Fusion Neutronics Source (FNS) facility has been started as the verification test of tritium production performance. This paper overviews the recent achievements of the development of the WCCB TBM in Japan. 相似文献
148.
Yuhei Ogawa Hisao Matsunaga Junichiro Yamabe Michio Yoshikawa Saburo Matsuoka 《International Journal of Hydrogen Energy》2018,43(43):20133-20142
The fatigue limit properties of a carbon steel and a low-alloy CrMo steel were investigated via fully-reversed tension-compression tests, using smooth specimens in air and in 115-MPa hydrogen gas. With respect to the CrMo steel, specimens with sharp notches were also tested in order to investigate the threshold behavior of small cracks. The obtained SN data inferred that the fatigue limit was not negatively affected by hydrogen in either of the steels. Observation of fatigue cracks in the unbroken specimens revealed that non-propagating cracks can exist even in 115-MPa hydrogen gas, and that the crack growth threshold is not degraded by hydrogen. The experimental results provide justification for the fatigue limit design of components that are to be exposed to high-pressure hydrogen gas. 相似文献
149.
Recently thermal utilizations of sewage sludge, especially pyrolysis and gasification, are regarded as promising technologies due to efficient utilization of fuel gas. In this study, characteristics of tar and NOx precursors were investigated during the pyrolysis of sewage sludge. Moreover, absorption performance for tar and NOx precursors were also studied by using four kinds of scrubbing mediums: cooking oil, diesel oil, BDF and water. The results showed that nitrogenous light PAHs were the major components of nitrogenous tar produced from the pyrolysis of sewage sludge. As for gravimetric tar and major nitrogenous tar compounds removal, cooking oil was the most suitable absorbent. With respect to NOx precursors, it was concluded that HCN, sharing of about 39.5% of total nitrogen of the sewage sludge, was the main NOx precursor gas whereas NH3 content could be neglected. Absorption capacity of hydrophobic scrubbing mediums against NOx precursor gases could be arranged as followed: diesel oil > cooking oil > BDF. 相似文献
150.
The objective of this study is to experimentally examine the characteristics of transient vortices in the boundary layer on a disk undergoing both rotation and orbital motion. The velocity fluctuations on a rotating, orbiting disk (disk radius equal to orbital radius) are measured by the hot-wire method, and the effects of orbital motion on the transient vortices in the boundary layer are examined. When the ratio of the orbital speed to the speed of rotation is i-0.025, the interval of transient vortices depends on only the orbital radius, regardless of the directions of rota- tion and orbital motion. The rate of low-frequency disturbances increases as the orbital speed increases, and the vortices induced by these low-frequency disturbances travel over the disk and then develop in the region of in- creased velocity. Consequently, no vortices generated on a rotating disk under orbital motion are stationary rela- tive to the disk. 相似文献