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1.
Tomohiro Toigawa Yasuhiro Tsubata Takeshi Kai Takuya Furuta Yuta Kumagai Tatsuro Matsumura 《溶剂提取与离子交换》2021,39(1):74-89
ABSTRACT Absorbed-dose estimation is essential for evaluation of the radiation tolerance of minor-actinide-separation processes. We propose a dose-evaluation method based on radiation permeability, with comparisons of heterogeneous structures seen in the solvent-extraction process, such as emulsions forming in the mixture of the organic and aqueous phases. A demonstration of radiation-energy-transfer simulation is performed with a focus on the minor-actinide-recovery process from high-level liquid waste with the aid of the Monte Carlo radiation-transport code PHITS. The simulation results indicate that the dose absorbed by the extraction solvent from alpha radiation depends upon the emulsion structure, and that from beta and gamma radiation depends upon the mixer-settler-apparatus size. Non-negligible contributions of well-permeable gamma rays were indicated in terms of the plant operation of the minor-actinide-separation process. 相似文献
2.
Effects of Winding Attachment Positions on Output Characteristics of Flux‐Modulating Synchronous Machines 下载免费PDF全文
Hirofumi Aoki Tadashi Fukami Kazuo Shima Toshihiro Tsuda Mitsuhiro Kawamura 《Electrical Engineering in Japan》2015,191(3):40-49
The flux‐modulating synchronous machine (FMSM) is a new type of multipole SM with nonoverlapping concentrated armature and field windings on the stator. This paper compares the output characteristics of two FMSMs through finite element analysis (FEA) and experiments. In both of the FMSMs, the attachment positions of the armature and field windings are swapped. To determine the reason for the discrepancies in their output characteristics, unsaturated inductances were calculated using a d‐‐q equivalent circuit. In addition, the calculated results of the inductances were confirmed through a visualization of the leakage fluxes using FEA. The results of the study show that the synchronous inductance can be reduced by attaching the armature winding to the air‐gap side of the stator teeth and that the reduction leads to an increase in output power. 相似文献
3.
Kazuo Tsubota Stephen C. Pflugfelder Zuguo Liu Christophe Baudouin Hyo Myung Kim Elisabeth M. Messmer Friedrich Kruse Lingyi Liang Jimena Tatiana Carreno-Galeano Maurizio Rolando Norihiko Yokoi Shigeru Kinoshita Reza Dana 《International journal of molecular sciences》2020,21(23)
Over the past decades, the number of patients with dry eye disease (DED) has increased dramatically. The incidence of DED is higher in Asia than in Europe and North America, suggesting the involvement of cultural or racial factors in DED etiology. Although many definitions of DED have been used, discrepancies exist between the various definitions of dry eye disease (DED) used across the globe. This article presents a clinical consensus on the definition of DED, as formulated in four meetings with global DED experts. The proposed new definition is as follows: “Dry eye is a multifactorial disease characterized by a persistently unstable and/or deficient tear film (TF) causing discomfort and/or visual impairment, accompanied by variable degrees of ocular surface epitheliopathy, inflammation and neurosensory abnormalities.” The key criteria for the diagnosis of DED are unstable TF, inflammation, ocular discomfort and visual impairment. This definition also recommends the assessment of ocular surface epitheliopathy and neurosensory abnormalities in each patient with suspected DED. It is easily applicable in clinical practice and should help practitioners diagnose DED consistently. This consensus definition of DED should also help to guide research and clinical trials that, to date, have been hampered by the lack of an established surrogate endpoint. 相似文献
4.
Noriyuki Wada Jyoji Hanai Mikiya Furukawa Kazuo Kojima 《Journal of the American Ceramic Society》2019,102(8):4621-4631
To make a Mn2+-doped red glass phosphor that can be excited with ultraviolet (UV) light of light-emitting diodes (LEDs), 60P2O5-35ZnO-5Al2O3-8MnO-xCu2O glasses (x = 0-1.00) were prepared by a melt-quenching method at 1200-1400°C for 30-180 minutes in atmospheric air, and the redox of Mn and Cu as well as fluorescence properties were investigated. The Mn2+ ion was not reduced and oxidized in the melting, quenching, and annealing processes. The valence of Cu in the glasses changed in the order of 0, 1+, and 2+ with the increase in the amount of Cu2O and in the melting temperature and time. In this study, a 60P2O5-35ZnO-5Al2O3-8MnO-0.10Cu2O glass melted at 1250°C for 90 minutes, having the highest Cu+ concentration, showed the strongest Mn2+ red fluorescence under the UV light at 275 nm. This strong Mn2+ red fluorescence has been caused by the energy transfer from excited Cu+ ions to Mn2+ ions. 相似文献
5.
Hiromichi Ichinose Masanori Taira Sachiko Furuta Hiroaki Katsuki 《Journal of the American Ceramic Society》2003,86(9):1605-1608
Niobium- or vanadium-doped anatase sols were prepared by hydrothermal treatment of 0.1 mol/dm3 peroxotitanium complex aqueous solutions dissolving 0–10 mol% niobium or vanadium at 100°C for 8 h. Niobium-doping caused the increase of lattice constants of anatase and the shape change of anatase crystal from spindle-like to cubic-like structure, but no change of the optical absorbance. Vanadium-doping caused the decrease of lattice constant of c -axis, the miniaturization of anatase crystal and the increase of optical absorbance at the wavelength from 350–700 nm. 相似文献
6.
Ichiro Hirosawa Tetsuo Honma Kazuo Kato Naoto Kijima Yasuo Shimomura 《Journal of the Society for Information Display》2004,12(3):269-273
Abstract— We studied the influence of annealing in air on doped europium in BaMgAl10O17 by performing x‐ray absorption fine‐structure measurements. We determined the oxidation of doped divalent europium by annealing in air at over 500°C. The interatomic distance between the europium and the surrounding oxygen atoms was compressed by oxidation. It also appears that the oxidation process of europium is determined by the diffusion of oxygen into BaMgAl10O17. 相似文献
7.
M Furuta K Hayakawa S Katano Y Saito Y Nakayama T Takahashi R Imai T Ebara N Mitsuhashi H Niibe 《Canadian Metallurgical Quarterly》1996,26(2):95-98
Vaccination with peptides that induce a specific immune response is a potential prophylactic or therapeutic strategy against viral infections and tumors. Because of the extensive polymorphism of the HLA loci, synthetic peptide vaccines must consist of a cocktail of peptides that bind specifically to different HLA molecules. Such cocktails should be optimized for the target population as each population has its specific HLA gene frequencies. To achieve maximum population coverage with a minimum number of peptides, information is needed on the ranking of the most frequent HLA phenotypes. We introduce the minimal phenotype panel, which is the smallest combination of HLA antigens selected so that the proportion of individuals in a population that express at least one of the antigens in the panel exceeds a desired minimum value. We developed a method for assembling minimal phenotype panels based on known HLA class I gene frequencies. We give an example based on a set of 2446 well-defined HLA-typed, random, healthy, unrelated, Dutch Caucasoid individuals. In addition, we discuss the possibility of assembling minimal phenotype panels based on two-locus haplotypes, which enables the assembly of phenotype panels from the antigens of both loci. 相似文献
8.
On an earthspace propagation path with the low elevation angle of 10 deg, the phase between co- and crosspolar signals occasionally showed rapid and irregular fluctuations during fine weather. These fluctuations were generally significant during the daytime, and were strongly in phase with the occurrence of the copolar amplitude scintillations. This could be attributed to the combined effects of the crosspolar phase pattern of the receiving antenna and small fluctuations of the angle of arrival of the radiowaves. 相似文献
9.
10.
Hiroto Imai Toshiyuki Ogawa Kazuo Sugimoto Masakazu Kataoka Yumo Tanaka Takehiko Ono 《Applied catalysis. B, Environmental》2005,55(4):259-265
The Co/MFI(SiO2/Al2O3 = 30) were prepared by a precipitation method with NaOCl in alkali solutions exhibited high activities to N2 at 250 °C for the selective catalytic reduction (SCR) of NOx. These catalysts showed two UV–vis bands at 700 and 400 nm, indicating the presence of octahedral Co(III) as well as tetrahedral Co(II). The high SCR activity over such Co(III, II)/MFI(30) seems to come from Co(III)---O moieties. The Co(II)MFI(30) catalysts prepared from Co(II)Cl2 exhibited low SCR activities due to the presence of tetrahedral Co(II) ions in MFI. Less CO formation occurred over Co/MFI catalysts. The Fe/MFI(30) catalyst exhibited high activity due to the presence of some Fe---O species in MFI but more amount of CO were produced during SCR. H/MFI(30) catalyst exhibited a good SCR activity. However, more amount of carbonaceous deposits were produced on it. The correlation between acid concentration and SCR activity was discussed over H/MFIs. 相似文献