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1.
Atsuki Yamaguchi Kazuki Fukui Yuki Fujiwara Shingo Tamaki Sachie Kusaka Fuminobu Sato 《Journal of Nuclear Science and Technology》2021,58(1):80-86
ABSTRACT It is important to perform neutron transport simulations with accurate nuclear data in the neutronics design of a fusion reactor. However, absolute values of large-angle scattering cross sections vary among nuclear data libraries even for well-examined nuclide of iron. Benchmark experiments focusing on large-angle scattering cross sections were thus performed to confirm the correctness of nuclear data libraries. The series benchmark experiments were performed at a DT neutron source facility, OKTAVIAN of Osaka University, Japan, by the unique experimental system established by the authors’ group, which can extract only the contribution of large-angle scattering reactions. This system consists of two shadow bars, target plate (iron), and neutron detector (niobium). Two types of shadow bars were used and four irradiations were conducted for one experiment, so that contribution of room-return neutrons was effectively removed and only large-angle scattering neutrons were extracted from the measured four Nb reaction rates. The obtained experimental results were compared with calculations for five nuclear data libraries including JENDL-4.0, JEFF.-3.3, FENDL-3.1, ENDF/B- VII, and recently released ENDF/B-VIII. It was found from the comparison that ENDF/B-VIII showed the best result, though ENDF/B-VII showed overestimation and others are in large underestimation at 14 MeV. 相似文献
2.
Shizuo Arichi Noriyuki Sakamoto Shozo Himuro Mayumi Miki Masafumi Yoshida 《Polymer》1985,26(8):1175-1180
In order to obtain the additional data concerning the unperturbed dimension of poly-4-substituted styrene, light scattering measurements are performed on the twenty-two fractions with molecular weight of (0.91–352)·104 of poly(4-acetoxystyrene) in dioxan at 25°C, from which the molecular weight obtained was found easily to be evaluated with the gel permeation chromatography using THF. Phase separation experiments for this polymer indicate that the theta state is attained in isopropyl acetate at 19.7°C and butyl acetate at 26.8°C. By making viscosity measurements at that state, the value of KΘ is directly evaluated as 5.4·10?4 dl g?1. The limiting viscosity number is also obtained in good solvents, THF and dioxan, at 25°C and constants of the Mark-Houwink-Sakurada equation in each solvent are determined. Further, approximately the same KΘ as above is obtained from these data with the Stockmayer-Fixman plot. The calculated value of steric factor, 2.37, on this polymer may be plausible, compared with those of polyvinylaromatic derivatives. 相似文献
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5.
Inaba S. Okano K. Matsuda S. Fujiwara M. Hokazono A. Adachi K. Ohuchi K. Suto H. Fukui H. Shimizu T. Mori S. Oguma H. Murakoshi A. Itani T. Iinuma T. Kudo T. Shibata H. Taniguchi S. Takayanagi M. Azuma A. Oyamatsu H. Suguro K. Katsumata Y. Toyoshima Y. Ishiuchi H. 《Electron Devices, IEEE Transactions on》2002,49(12):2263-2270
The 35 nm gate length CMOS devices with oxynitride gate dielectric and Ni salicide have been fabricated to study the feasibility of higher performance operation. Nitrogen concentration in gate oxynitride was optimized to reduce gate current I/sub g/ and to prevent boron penetration in the pFET. The thermal budget in the middle of the line (MOL) process was reduced enough to realize shallower junction depth in the S/D extension regions and to suppress gate poly-Si depletion. Finally, the current drives of 676 /spl mu/A//spl mu/m in nFET and 272 /spl mu/A//spl mu/m in pFET at V/sub dd/=0.85 V (at I/sub off/=100 nA//spl mu/m) were achieved and they are the best values for 35 nm gate length CMOS reported to date. 相似文献
6.
Poly(l-lactide) (i.e. poly(l-lactic acid) (PLLA)) and poly(d-lactide) (i.e. poly(d-lactic acid) (PDLA)) and their equimolar enantiomeric blend (PLLA/PDLA) films were prepared and the effects of enantiomeric polymer blending on the thermal stability and degradation of the films were investigated isothermally and non-isothermally under nitrogen gas using thermogravimetry (TG). The enantiomeric polymer blending was found to successfully enhance the thermal stability of the PLLA/PDLA film compared with those of the pure PLLA and PDLA films. The activation energies for thermal degradation (ΔEtd) were evaluated at different weight loss values from TG data using the procedure recommended by MacCallum et al. The ΔEtd values of the PLLA/PDLA, PLLA, and PDLA films were in the range of 205-297, 77-132, and 155-242 kJ mol−1 when they were evaluated at weight loss values of 25-90% and the ΔEtd value of the PLLA/PDLA film was higher by 82-110 kJ mol−1 than the averaged ΔEtd value of the PLLA and PDLA films. The mechanism for the enhanced thermal stability of the PLLA/PDLA film is discussed. 相似文献
7.
A solid oxide fuel cell constructed from Ni-SDC anode and LSGM electrolyte was applied to the partial oxidation of methane to syngas (CO+H2) at 700-800 °C with the merits of co-generation of electricity and controllable O2 supply. It was found that the co-generated syngas at H2/CO ratio of 1.4-2.0 varied with applied current densities, CH4 flow rates and operating temperatures. The cell voltage at 100 mA cm−2 and 800 °C was 0.90 V, i.e. about 90 mW cm−2 power density could be obtained. The cell operating at 50 mA cm−2 for 24 h almost showed no degradation of the cell performance. The observed carbon deposition seemed mainly taking place by CH4 cracking reaction. 相似文献
8.
Toshiaki Enoki Yousuke Kobayashi Chika Katsuyama Vladimir Yu. Osipov Marina V. Baidakova Kazuyuki Takai Ken-ichi Fukui Alexander Ya. Vul'' 《Diamond and Related Materials》2007,16(12):2029-2034
The structure, electronic and magnetic properties of nanodiamond and nanographite/nanographene are investigated. Detonation nanodiamond particles that are covered with amorphous graphitic composites are hydrothermally treated to remove the graphitic surface composites and to terminate the surface carbon atoms with hydrogen. The number of localized spins of dangling bonds and the hydrogen concentration increase upon the increase in the hydrothermal treatment time up to 40 h. Above 40 h, both drop discontinuously, a surface structural reconstruction was suggested. The creation of dangling bonds and an incomplete hydrogenation of the surface carbon atoms destabilize the surface, resulting in the structural reconstruction. Nanodiamond particles are thermally converted to nanographite/nanographene. A single nanographene sheet is successfully prepared by heat-treating nanodiamond particles. The edge of graphene sheet with its edge carbon atoms being hydrogen-terminated is investigated by UHV-STM/STS. Zigzag edges are found to have non-bonding π-state of edge origin, in good agreement with theoretical prediction. 相似文献
9.
Bis-(monoacylglyceryl) phosphate and acyl phosphatidylglycerol were isolated from the liver of two patients with lipidosis
induced by 4,4′-diethylaminoethoxyhexesterol. Identification was based upon the results of alkaline hydrolysis, acetolysis,
IR spectrometry, and upon the determination of molar ratio of phosphorus-glycerol-ester. The contents of the bis-(monoacylglyceryl)
phosphate were 10 and 16% total phospholipid phosphorus in them. The bis-(monoacylglyceryl) phosphate contained mainly docosahexaenoic
(42%), oleic (29%), and linoleic acid (14%) and had the hemolytic activity of ca. one-eighth lysolecithin from egg yolk. Acidic
lipids from the liver also were found to contain a lipid which is less polar than bis-(monoacylglyceryl) phosphate. The results
of lipid analysis showed that the lipid possessed the structure of an acyl phosphatidylglycerol, and its content was ca. 2%
total phospholipid phosphorus. Accumulation of 4,4′-diethylaminoethoxyhexesterol and its derivatives was found in clinical
cases by thin layer chromatography and IR spectrometry. This fact suggested that human liver has an ability to metabolize
the drug. 相似文献
10.
Functionally graded materials (FGMs) belong to a relatively new class of inhomogeneous composite materials, in which the composition
and/or microstructure undergo a gradual change along some directions. In this review article, the microstructures and composition
gradients in Al/SiC, Al/Shirasu (volcanic eruptions commonly found in south Kyushu in Japan), Al/Al3Ti, Al/Al3Ni, Al/Al2Cu FGMs have been investigated. The Al/SiC, Al/Shirasu and Al/Al3Ti FGMs are fabricated by the centrifugal solid particle method where the distribution particles of SiC, Shirasu and Al3Ti are solids in the melts. On the other hand, Al/Al3Ni and Al/Al2Cu FGMs are fabricated by the centrifugalin-situ method where Al/Al3Ni and Al/Al2Cu systems have lower liquidus temperatures than the processing temperatures. The feature of Al/(Al3Ti−Al3Ni) hydrid FGM, which is fabricated by a method combining both the centrifugal solid-particle andin-situ methods, is also shown. 相似文献