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91.
Study on explosion characteristics of natural gas and methane in semi-open space for the HTTR hydrogen production system 总被引:1,自引:0,他引:1
Yoshitomo Inaba Tetsuo Nishihara Mark A Groethe Yoshikazu Nitta 《Nuclear Engineering and Design》2004,232(1):111-119
It is important to grasp the explosion characteristics of object gases: natural gas and methane, in order to evaluate the influence of a gas explosion accident in the HTTR hydrogen production system on the reactor. Thus, we carried out explosion experiments of the object gases in semi-open space, and verified a numerical analysis code for the simulation of the explosion accident. It was confirmed that NG–air mixture or methane-air mixture in semi-open space did not result in DDT although 10 g of C-4 explosive was used as an ignition source, and the numerical results agreed relatively with the experimental results. As a result, we could have the prospects for predicting the influence of the explosion accident on the reactor. 相似文献
92.
A 19-year-old male consulted our department, complaining of a painful scrotal mass. On palpation, the mass was discriminated from testis, epididymis, and spermatic cord in the left scrotum. He underwent total excision of the mass. Pathologic examination revealed cavernous hemangioma. Scrotal hemangioma is a relatively rare lesion and this is the 37th case reported in Japan. 相似文献
93.
N Fukuyama S Takizawa H Ishida K Hoshiai Y Shinohara H Nakazawa 《Canadian Metallurgical Quarterly》1998,18(2):123-129
The plasma pharmacokinetics of danofloxacin administered at 1.25 mg kg-1 body weight by the intravenous and intramuscular routes were determined in sheep. Tissue distribution was also determined following administration by the intramuscular route at 1.25 mg kg-1 body weight. Danofloxacin had a large volume of distribution at steady state (Vdss) of 2.76 +/- 0.16 h (mean +/- S.E.M.) L kg-1, an elimination half-life (t1/2 beta) of 3.35 +/- 0.23 h, and a body clearance (C1) of 0.63 +/- 0.04 L kg-1 h-1. Following intramuscular administration it achieved a maximum concentration (Cmax) of 0.32 +/- 0.02 microgram mL-1 at 1.23 +/- 0.34 h (tmax) and had a mean residence time (MRT) of 5.45 +/- 0.19 h. Danofloxacin had an absolute bioavailability (F) of 95.71 +/- 4.41% and a mean absorption time (MAT) of 0.81 +/- 0.20 h following intramuscular administration. Mean plasma concentrations of > 0.06 microgram mL-1 were maintained for more than 8 h following intravenous and intramuscular administration. Following intramuscular administration highest concentrations were measured in plasma (0.43 +/- 0.04 microgram mL-1), lung (1.51 +/- 0.18 micrograms g-1), and interdigital skin (0.64 +/- 0.18 microgram g-1) at 1 h, duodenal contents (0.81 +/- 0.40 microgram mL-1), lymph nodes (4.61 +/- 0.35 micrograms g-1), and brain (0.06 +/- 0.00 microgram mL-1) at 2 h, jejunal (10.50 +/- 4.31 micrograms mL-1) and ileal (5.25 +/- 1.67 micrograms mL-1) contents at 4 h, and colonic contents (8.94 +/- 0.65 micrograms mL-1) at 8 h. 相似文献
94.
This paper presents an application of parallel genetic algorithms (PGA) to the optimal long-range generation expansion planning. The problem can be formulated as a combinatorial optimization problem that determines the order of introduced generation units at each interval of the year. The proposed method considers introduced power limits of each technology, maximum loads at each interval, and load duration curves at each interval. Appropriate string representation for the problem is presented. Binary and decimal coding and three selection methods are compared. The method is developed on a transputer that is one of the parallel processors. The feasibility of the proposed method is demonstrated using a typical expansion problem with four technologies and five intervals. The method is then compared with conventional dynamic programming and a simple genetic algorithm with promising results. 相似文献
95.
1IntroductionCharacterswerecreatedasamediumofcommunication.Forexample,theyhavebeenusedtorecordsocialactivitiesandhumanthinking,andtohelppeoplesexchangeinformation.Differencesfrommanyothercharacters,however,theChi-nesecharacterisatypicalideograph.BecauseChinesecharactersoriginatedfromdrawings,theirshapeshavetheelementsofbeauty.InChina,calligraphyaboutChinesecharactershasbeenanimportanpartofartsinceancienttimes.There-sultsofstudiesaboutcalligraphyhavebeenbequeathedascalligraphicworksandcallig… 相似文献
96.
M. Hayashi M. Murata H. Fukuyama K. Nagata 《Metallurgical and Materials Transactions B》2002,33(1):47-54
The wavelength and composition dependencies of normal spectral emissivities for liquid Ag-Cu alloys have been measured over
a wavelength range between 450 and 1500 nm at temperatures from 1273 to 1423 K in a cold crucible furnace. The spectral emissivities
abruptly increase in the visible region with decreasing wavelength. The wavelength at the abrupt increase in the emissivity
shifts to a shorter wavelength as the concentration of silver in the alloy increases. This suggests that the abrupt increases
are attributed to the direct interband transition, and the energy gap between the d band and the Fermi level increases with an increase in silver concentration in the alloy. To the contrary, the spectral emissivities
in the infrared region were found to exhibit weak negative wavelength dependencies, which are attributed to the intraband
transition. The composition dependencies of spectral emissivities observed in the infrared region have been explained by the
Drude model. 相似文献
97.
H Yamauchi H Fukuyama Y Nagahama Y Katsumi Y Dong J Konishi J Kimura 《Canadian Metallurgical Quarterly》1996,53(11):1103-1109
BACKGROUND: The independent influences of small-intestinal bacterial overgrowth and old age on mucosal immunoglobulin production and secretion have not been assessed. This is an important issue, since luminal IgA deficiency may exacerbate small-intestinal bacterial overgrowth, the prevalence of which is high in selected elderly populations. METHODS: Proximal small-intestinal aspirates were obtained from 33 subjects for bacteriologic analysis and measurement of total IgA, IgM, total IgG. IgG subclass, and IgD concentrations. IgA subclasses were measured in 24 unselected subjects. Serum immunoglobulin and salivary IgA concentrations were measured in all subjects. RESULTS: IgA2 and IgG3 were predominant IgA and IgG subclasses in proximal small-intestinal luminal secretions. Luminal concentrations of IgA2 and IgM, but not IgG3 or any other IgG subclass, were significantly increased in small-intestinal bacterial overgrowth, which was present in 19 of 33 (57.6%) subjects. Old age did not influence these levels. Luminal immunoglobulin concentrations did not correlate significantly with either serum or salivary values. IgD was not measureable in proximal small-intestinal secretions. CONCLUSIONS: Increased luminal concentrations of the secretory immunoglobulins, IgA2 and IgM, occur in small-intestinal bacterial overgrowth. Local investigation is mandatory when assessing the mucosal immunopathology of this disorder. Luminal IgG3 is unlikely to be predominantly derived from serum. Old age does not independently influence luminal immunity. 相似文献
98.
Masahiro Tabata Yoshikazu Nishida Tatsuya Kodama Keisuke Mimori Takashi Yoshida Yutaka Tamaura 《Journal of Materials Science》1993,28(4):971-974
An oxygen-deficient Mn(II) ferrite (Mn0.97Fe2.02O3.92) was synthesized and its reactivity to reduce CO2 gas into carbon was studied at 300°C. The oxygen-deficient Mn(II) ferrite was obtained by flowing H2 gas through Mn(II) ferrite with a nearly stoichiometric composition of Mn0.97Fe2.02O4.00 at 300° C. The lattice constant of the oxygen-deficient Mn(II) ferrite (0.8505nm) is larger than that of the Mn(II) ferrite with a nearly stoichiometric composition (0.8498nm). The chemical composition of the Mn(II) ferrite changed from Mn0.97Fe2.02O4.00 to Mn0.97Fe2.02O3.92 during the H2 reduction process, indicating that the oxygen is deficient in the spinel structure of the Mn(II) ferrite. This was confirmed by Mössbauer spectroscopy and X-ray diffractometry. The efficiency of CO2 decomposition into carbon at 300°C with the oxygen-deficient Mn(II) ferrite was much lower by about 105 than that of oxygen-deficient magnetite. This is considered to be due to the difference in electron conductivity between Mn(II) ferrite and magnetite, which determines the reductivity for CO2 into carbon by donation of an electron at the adsorption site. 相似文献
99.
Wire breakage by arc fusion due to lightning flashovers has become a serious problem in Japan as a result of the widespread use of insulated wires as distribution lines. To solve this problem, a current-limiting arcing horn that has a nonlinear resistor element of zinc oxide has been developed. With this element the power follow current is interrupted and conductor arc fusion is prevented. Even in the case of bare wires, this device effectively prevents power-supply service interruptions. The design and performance of the device and its ability to prevent lightning faults on actual distribution lines are described 相似文献
100.
T Yano Y Fukuyama H Yokoyama S Kuninaka Y Terazaki T Uehara H Asoh Y Ichinose 《Canadian Metallurgical Quarterly》1998,14(2):152-155
OBJECTIVE: To determine the distribution and significance of microcalcifications in histologic sections of the prostate. DESIGN: Retrospective review of all histologic slides of completely embedded prostates from surgical specimens. MATERIALS: Randomly selected material included 266 radical prostatectomy and 10 cystoprostatectomy prostates without prostate cancer. Nonrandomly selected specimens included 26 radical prostatectomy specimens with a Gleason pattern 5 component, 24 cases with collagenous micronodules, and 8 cases previously noted to have microcalcifications within foci of prostate cancer. RESULTS: Four patterns of microcalcifications were noted in association with prostate cancer: (1) dystrophic calcification in the comedo-type necrosis of Gleason pattern 5, (2) intraluminal calcification in cribriform-type Gleason pattern 3 prostate cancer, (3) intraluminal calcification in small acinar adenocarcinoma, and (4) stromal calcification within collagenous micronodules associated with prostate cancer. Microcalcifications were noted in 32% of prostates without cancer; 1.9% of randomly selected prostates demonstrated microcalcifications associated with prostate cancer. CONCLUSIONS: Microcalcifications are less common in association with prostate cancer than with benign prostatic ducts and acini. However, intraluminal microcalcifications associated with an atypical small glandular proliferation should not be taken as unequivocal evidence of a benign process. 相似文献