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141.
Koichi Hata Yuto Takeuchi Masahiro Shiotsu Akira Sakurai 《Nuclear Engineering and Design》1999,194(2-3)
Rigorous numerical solution of natural convection heat transfer, from a horizontal cylinder with uniform surface heat flux or with uniform surface temperature, to liquid sodium was derived by solving the fundamental equations for laminar natural convection heat transfer without the boundary layer approximation. It was made clear that the local and average Nusselt numbers experimentally obtained and reported in part 1 of this paper were described well by the numerical solutions for uniform surface heat fluxes, but that those for uniform surface temperatures could not describe the angular distribution of the local Nusselt numbers and about 10% underpredicted the average Nusselt numbers. Generalized correlation for natural convection heat transfer from a horizontal cylinder with a uniform surface heat flux in liquid metals was presented based on the rigorous theoretical values for a wide range of Rayleigh numbers. It was confirmed that the correlation can describe the authors’ and other workers’ experimental data on horizontal cylinders in various kinds of liquid metals for a wide range of Rayleigh numbers. Another correlation for a horizontal cylinder with a uniform surface temperature in liquid metals, which may be applicable for special cases such as natural convection heat transfer in a sodium-to-sodium heat exchanger etc. was also presented based on the rigorous theoretical values for a wide range of Rayleigh numbers. These correlations can also describe the rigorous numerical solutions for non-metallic liquids and gases for the Prandtl numbers up to 10. 相似文献
142.
K Ishihara H Ichikawa T Takeuchi M Kawamura K Sugita 《Canadian Metallurgical Quarterly》1997,37(6):509-513
We describe a patient who presented with isolated retrograde amnesia of 2-year duration after recovery from viral encephalitis. The patient was a 29-year-old right-handed male dentist and was admitted to our hospital with a complaint of generalized convulsion. Cerebrospinal fluid (CSF) showed mononuclear pleocytosis. Neuroradiological examinations (X-ray CT, MRI and 123I-IMP SPECT) revealed no significant abnormality. Immunological method showed no specific increase of viral antibody titers. However, with a tentative diagnosis of viral encephalitis, administration of acyclovir was started. After 3 weeks he became comprehensive, and several kinds of neuropsychological tests were performed. His intelligence and immediate memory were normal, and his procedural memory of dentist was intact. On the other hand, he could not recall any information about events, both personal and public, occurred within 2 years before the onset of present illness. His autobiographical memory disorder was also demonstrated using a series of weekly comic. In isolated retrograde amnesia following viral encephalitis like this case, memory of relatively short time duration, acquired prior to the onset of present illness, tend to be disturbed. 相似文献
143.
Y. Takeuchi Author Vitae H. Yonekura Author Vitae Author Vitae 《Computer aided design》2003,35(4):403-409
The study deals with the creation of a 3-dimensional (3-D) complicated tiny statue by means of a 5-axis control ultraprecision machining center and a pseudo ball end mill of single crystal diamond. In recent years, 3-D microstructures are required to provide components for micromechanism as well as metal molds and dies. Thus, as an example of complicated 3-D microstructures, a Buddha head of 3 mm in size was created, based on the scanned data of an actual statue. A control program developed in the study enables a diamond tool to feed around the head and to move from the top of the head to the neck not only by 4-axis control but also by 5-axis control to prevent the tool and its holder from colliding with a workpiece. As a result, a tiny Buddha head could be created with high surface quality. 相似文献
144.
Hiu Yung Wong Takeuchi H. Tsu-Jae King Ameen M. Agarwal A. 《Electron Device Letters, IEEE》2005,26(4):234-236
Pulsed excimer laser annealing (ELA) is used to reduce the poly-Si gate depletion effect (to <0.1 nm). Low resistivity (0.58 m/spl Omega//spl middot/cm) and high active boron concentration (4/spl times/10/sup 20/ cm/sup -3/) at the gate-oxide interface are achieved while preserving the gate oxide quality and avoiding boron penetration, to meet International Technology Roadmap for Semiconductors requirements for sub-65-nm CMOS technology nodes. ELA is compatible with high-/spl kappa/ dielectric (HfO/sub 2/) and results in significantly lower gate leakage current density as compared with rapid thermal annealing (RTA). 相似文献
145.
An autopsy case of cytokeratin 7-positive minute adenocarcinoma of the lung with systemic metastases
Y Ise H Yanagawa T Hirose K Tani S Yano Y Suzuki E Takeuchi K Maniwa E Shimizu F Ogushi T Sano S Sone 《Canadian Metallurgical Quarterly》1998,37(9):766-769
We describe a 60-year-old woman with leg pain. Although metastatic bone tumor and atypical cells mimicking signet-ring cells in the bone marrow picture were observed, systemic survey revealed no primary lesion. The patient died two months after admission from systemic progress of the disease. Autopsy revealed a small focus of adenocarcinoma within the right upper lobe of the lung and systemic metastases without any particular changes in the gastrointestinal tract. The tumor cells of the lung were diffusely positive for cytokeratin 7, whereas cytokeratin 20 immunoreactivity was weak and focal, and that supported the lung origin of the present tumor. Moreover, the tumor cells in the bone marrow showed a similar pattern in immunoreactivity. These findings suggest that cytokeratin 7 and cytokeratin 20 immunoreactivity is helpful for the premortem diagnosis of the metastatic tumor of unknown origin. 相似文献
146.
To clarify the mechanisms of intracellular induction of oxidative DNA damage, we have investigated the concentrations of intracellular reactive oxygen species and the amounts of 8-hydroxydeoxyguanosine (8OHdG), a mutagenic oxidative DNA damage, in human neutrophil-like cells, dimethylsulfoxide-differentiated HL60 (DMSO-HL60). We determined intracellular concentrations of hydrogen peroxide and superoxide by flow cytometry with dichlorofluorescein diacetate and hydroethidine, respectively. We determined the 8OHdG amounts with an electrochemical detector connected to HPLC after anaerobic sample processing. DMSO-HL60 releases superoxide upon stimulation with phorbol myristate acetate, and the released superoxide dismutates to hydrogen peroxide. Stimulation of DMSO-HL60 with 100 nM phorbol myristate acetate increased intracellular hydrogen peroxide, superoxide and 8OHdG (control). Addition of 1000 U/ml catalase decreased hydrogen peroxide (31.3% of control) and 8OHdG (20.3%). Addition of 100 U/ml SOD decreased superoxide (18.7%) and 8OHdG (41.6%). Addition of 1 mM deferoxamine decreased 8OHdG (30.4%), but increased hydrogen peroxide (129.6%). Addition of 200 microM 4-acetamido-4'- isothiocyanostilbene-2,2'-disulfonic acid decreased superoxide (59.9%) and 8OHdG (42.0%). Addition of 0.4% ethanol had no effect on superoxide concentration (102.2%), but tended to decrease hydrogen peroxide (83.5%) and 8OHdG (84.3%). Pretreatment of DMSO-HL60 with 0.1 mM FeSO4 increased 8OHdG (117.3%), but decreased hydrogen peroxide (75.8%). These findings indicate that the extracellularly released superoxide and hydrogen peroxide diffuse into the cell, but that such reactive oxygen species are not the direct molecules to induce 8OHdG. Our results suggest that 8OHdG is induced by the hydroxyl radical which is generated from intracellular hydrogen peroxide and superoxide-reduced Fe. 相似文献
147.
T Takahashi Y Takasaki K Takeuchi K Yamanaka K Oshimi H Hashimoto 《Canadian Metallurgical Quarterly》1997,28(1-2):113-125
The proximity of farms to badger setts was compared between farms that had experienced a tuberculosis breakdown and those that had not, over the 6 year period from 1988 to 1993. The data were derived from a badger removal study conducted in East Offaly County in the Republic of Ireland. Badger removal began in 1989 and continued through 1993; by the end of 1990, approximately 80% of all badgers caught in the 6 year period had been removed. All badgers were examined, grossly, for evidence of tuberculosis. Tuberculosis status of the approximately 900 study herds was based on the results of the single intradermal comparative skin test and/or lesions of bovine tuberculosis. All herds were tested at least once annually. The number of herds experiencing bovine tuberculosis declined over the period, particularly in the years 1992 and 1993. The data on farm and badger sett location were stored and analysed, initially, in a geographical information system. Owing to the badger removal programme, the distance between the barn yard of a typical farm and the nearest occupied badger sett increased, by about 300 m year-1, and by about 600 m year-1 to the closest infected sett. In bivariate analyses, in the years 1988 and 1989, the risk of tuberculosis declined with increasing distance to a badger sett containing one or more tuberculous badgers. In multivariable logistic regression analyses, year and the average number of cattle tested per farm per year were controlled. A second identical analysis was conducted to control for the repeated observations on the same herds using generalised estimating equations. In both analyses, the risk of a multiple reactor tuberculosis breakdown decreased for herds at least 1000 m away from an infected badger sett, and increased as the number of infected badgers per infected sett increased. Despite the significantly reduced risk of a breakdown with increasing distance to infected badger setts, the relationship was not strong (sensitivity and specificity of the model in the low 70% range) and explained only 9-19% of tuberculosis breakdowns. 相似文献
148.
We have investigated Pb(Zr,Ti)O3 (PZT) film composition suitable for highly reliable ferroelectric RAM (FeRAM) application. To obtain a wide operational margin for 2T/2C (two transistors and two capacitors) FeRAMs, the PZT film capacitor is needed to have a low coercive voltage (Vc) and a high dielectric constant on the polarization switching (ϵS) and a low dielectric constant on the nonswitching (ϵN), or essentially a large ϵS/ϵN ratio. Concerning the B-site composition in the perovskite structure, it is found that lowering the Zr/Ti ratio from 47/53 to Ti-richer ones increases the ratio of ϵS/ϵN as a positive effect on the wide operational margin, but increased Vc as a negative effect. Taking the balance of these factors into consideration, it is concluded that an optimum composition, such as Zr/Ti=30/70, provides the maximum operational margin. The A-site composition, on the other hand, affects the long-term reliability of a PZT capacitor. The endurance to the fatigue and imprint are enhanced by reduction of the Pb-excess and dope of La in the A-site. A La-doped PZT (Zr/Ti =30/70) capacitor is successfully integrated to the 8 kbit FeRAM macro with double-layer Al wiring to confirm the feasibility of this capacitor 相似文献
149.
T Kondo O Matsuura N Takeuchi O Kuriki O Kamihira Y Hashimoto S Ohshima 《Canadian Metallurgical Quarterly》1997,43(11):795-798
A 39-year-old man was referred to our hospital with right testicular swelling. Ultrasonography and magnetic resonance imaging revealed bilateral, synchronous testicular tumors. Bilateral high inguinal orchiectomy was performed. Histological examination revealed anaplastic seminomas. Prophylactic radiation therapy was performed in the para-aortic and pelvic regions postoperatively, and no signs of metastasis have been found during the follow-up period of more than 5 months. Including the present case, 186 cases of bilateral testicular tumors reported in Japan are reviewed. 相似文献
150.
Sung-Sik Lee Mitsuhiro Nakamura Yasushi Takeuchi 《Korean Journal of Chemical Engineering》1989,6(2):81-87
Demulsification of stable oil-in-water emulsion was studied using powder adsorbent. Among various adsorbents tested, activated
carbon was found to be the most efficient regardless of the type of surfactants used. The more dose of activated carbon for
the demulsification was required, the higher concentration of the surfactant as well as the larger amount of oil and the bigger
size of the lipophilic and hydrophilic groups.
Empirical equations were obtained to correlate the dose of activated carbon to the residual concentration of oil as a function
of the initial concentration of surfactant. 相似文献