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排序方式: 共有771条查询结果,搜索用时 62 毫秒
71.
Nikolas A. Vrettos Hironobu Imakoma Morio Okazaki 《Chemical Engineering and Processing: Process Intensification》1989,26(3):237-246
In this work a way of calculating effective transport coefficients from the microgeometry of a porous medium is presented. The model material consists of a random packing of uniform spheres, and by applying the Voronoi—Delaunay tessellation technique the void between the spheres is simulated as a network of cylindrical pores. The tessellation yields all the necessary information for the structural characterization, such as the pore diameter, pore angle and pore length distribution functions and the topological interconnection. The effective transport coefficients of ordinary diffusion, Knudsen flow and viscous flow are calculated numerically by mass balancing at each network node and over all nodes of the system. The results obtained agree very well with the experimental ones, especially for ordinary diffusion. For Knudsen and viscous flow, inaccuracies in the estimation of the pore overlapping volume cause a relative error between the numerical and experimental results of the order of 16%–33%. 相似文献
72.
Lianzhou Wang S. Velu S. Tomura F. Ohashi K. Suzuki M. Okazaki T. Osaki M. Maeda 《Journal of Materials Science》2002,37(4):801-806
A new series of mesoporous silica spheres containing nanodispersed copper oxides were synthesized in H2O/EtOH/ammonia solution at room temperature. The mesoporous structures were characterised using X-ray powder diffraction and N2 adsorption-desorption techniques. Scanning electron micrograph and transmission electron micrograph revealed that the MCM-41 particles have spherical morphologies. The DTA curve of pure MCM-41 exhibited a sharp single exothermic peak between 290°C and 340°C, while a broad peak with several shoulders in the temperature range between 180°C and 380°C was observed for Cu-MCM-41, indicating the possible complexation of Cu2+ with surfactants adhering to the inner surfaces of the mesopores. Electron paramagnetic resonance spectra of uncalcined samples revealed that Cu2+ ions are in an octahedral or distorted octahedral coordination with nitrogen ligands of the surfactant while in the calcined samples they are coordinated with oxygen of the MCM-41 framework. The redox properties of samples were examined by a temperature-programmed reduction and N2O passivation method. The results indicate that CuO with increasing particle size could be formed in the mesoporous materials with increasing Cu contents, and this decreased the reducibility of the resulting CuO. 相似文献
73.
Y Yoshida A Moriya K Kitamura M Inazu N Okimoto Y Okazaki T Nakamura 《Canadian Metallurgical Quarterly》1998,13(6):1011-1022
Thirty-six beagles, 18 months of age, underwent ovariohysterectomy (OHX) or a sham operation. Sham-operated animals were given a diet with standard calcium (1.4%) (group 1, n = 6) or a restricted calcium diet (0.14%) (group 2, n = 6). The OHX animals were given the restricted calcium diet and YH529 orally with respective daily doses of 0, 0.02, 0.1, and 0.5 mg/kg of body weight (groups 3-6, n = 6 each) for 12 months. At the end of this period, the lumbar bone mineral densities (BMDs) in groups 2 and 3 and the load values for group 3 were significantly smaller than those for group 1. The midfemur BMD did not differ among the groups. The urinary deoxypyridinoline (U-Dpy) and bone formation rates (BFR/BS, BFR/BV) in groups 2 and 3 and the osteonal BFR/BS and trabecular osteoclast number (Oc.N/BS) in group 3 were significantly larger than the respective values for group 1. However, these parameters did not significantly differ between groups 2 and 3. The serum osteocalcin (OC) level, wall thickness (W.Th), and mineral apposition rate values for group 3 were significantly larger than those for group 2. In group 2, the trabecular activation frequency (Ac.F) increased by 3.11 times, and the percent values of the number of labeled osteons (L-Ot.N/T-Ot.N, %) in the tibia by 3.28 times over those for group 1. In group 3, the Ac.F increased by 3.20 times and the number of labeled osteons by 3.77 times over those for group 1. In groups 4-6, the U-Dpy and Oc.N/BS values were smaller, but their OC levels did not significantly differ from the level for group 3. The lumbar BMD, the load, and W.Th were dose-dependently significantly larger than those for group 3. The Ac.F values were significantly smaller, and the respective value in groups 4-6 was 67.9, 25.5, and 10.2% of that in group 3. The BMDs of the midfemur in groups 4-6 were significantly larger than those in group 3, but the ultimate load values did not significantly differ. The L-Ot.N/T-Ot.N values were also significantly smaller, and the respective value in groups 4-6 was 82.0, 48.5, and 55.2% of that in group 3. The tibial endocortical and periosteal BFR/BSs did not differ significantly. These data demonstrate that the effects of OHX on bone mass and turnover were small in the beagles fed a restricted calcium diet. YH529 maintained the mass and strength of the lumbar bone by reducing the bone resorption. The cortical bone appeared to be less sensitive to the agent than the trabecular bone in this animal model. 相似文献
74.
The diameter of callus in leg lengthening: 28 tibial lengthenings in 14 patients with achondroplasia
K Mamada K Nakamura T Matsushita H Okazaki R Shiro W Ou K Tanaka T Kurokawa 《Canadian Metallurgical Quarterly》1998,69(3):306-310
A 46-year-old man who had been pulled under water by a tidal wave when an earthquake occurred on July 12, 1993 was carried to our hospital the next day. He soon needed endotracheal intubation and mechanical ventilation because he expectorated sputa with sand and because arterial bloodgas analysis revealed severe hypoxemia. Chest X-ray on admission showed diffuse small nodules and areas of consolidation. Chest CT obtained on July 16 showed centrilobular small nodules bilaterally and alveolar opacities in the peribronchial region. After therapy with antibiotics and frequent bronchial lavages, sputum with sand disappeared on the 14 th hospital day and chest X-ray film and laboratory data showed marked improvement. He was discharged on October 1. A chest CT scan obtained on February 17, 1994 showed improvement of the small nodules. The areas of consolidation had also improved, but remained as linear and nodular opacities, which were considered to be organized lesions. There are few reports concerning radiographic findings particularly CT findings, after aspiration of sea water and sand during near drowning. 相似文献
75.
M Kojima N Tsutsumi H Nagata F Itoh A Ujiie K Kawashima H Endo M Okazaki 《Canadian Metallurgical Quarterly》1994,17(4):504-508
The effect of 3,9-bis(N,N-dimethylcarbamoyloxy)-5H-benzofuro[3,2-c]quinoli ne-6-one designated as KCA-098) on the bone mineral metabolism of chick embryonic bone was examined. KCA-098 dose-dependently inhibited bone resorption of cultured chick embryonic femora and calvariae. It increased the length, dry weight, and calcium and phosphorus contents of 9-d-old chick embryonic femurs cultivated for 6 d, indicating that it stimulated bone formation. These results show that KCA-098 has the unique effects of inhibiting bone resorption and stimulating bone formation of chick embryo. In addition, in an in vivo experiment, oral administration of KCA-098 (3.0 mg/kg/d) for 16 weeks led to an increase in calcium and phosphorus content as well as an increase in the amount of force required to break the femur from ovariectomized rats, suggesting that it may be useful for the treatment of bone diseases. 相似文献
76.
N-Nitroso-N-methylvinylamine was synthesized and treated with dimethyldioxirane to produce 1-(N-nitrosomethylamino)oxirane. 1-(N-Nitrosomethylamino)oxirane had a t1/2 of < 5 s in buffer at neutral pH and 23 degrees C. This epoxide reacted with Ado to form 1,N6-etheno(epsilon-)Ado. It also reacted with DNA to form products arising from the oxirane portion of the molecule [N7-(2-oxoethyl)Gua,N2,3-epsilon-Gua, and 1,N6-epsilon-dAdo] and the methyl group (N7-methylGua). NADPH-fortified rat liver microsomes oxidized N-nitroso-N-methylvinylamine to form 1,N6-epsilon-Ado in the presence of Ado. Further, 1,N6-epsilon-Ado was also formed in microsomal incubations containing N-nitroso-N-methylethylamine, indicating that desaturation of the ethyl moiety occurs to form a vinyl group and then an epoxide. When NADPH-fortified microsomes were incubated with N-nitroso-N-methylvinylamine, HCHO was formed, and when DNA was included in incubations, 1,N6-epsilon-dAdo and N7-methylGua were isolated from DNA. In the cases of both HCHO and N7-methylGua, product formation was similar to the levels seen with N-nitroso-N,N-dimethylamine and N-nitroso-N-methylethylamine. 相似文献
77.
A 52-year-old male gardener, who traveled to Guam Island several days ago, was admitted to our hospital with fever, cough and dyspnea. His chest X-ray showed bilateral infiltration and he was severely hypoxic and hypotensive on admission. He died of multiple organ failure in spite of intensive treatment with mechanical ventilation antibiotics including erythromycin. Legionella longbeachae serotype 1 was isolated from his sputum and was regarded as the etiologic agent. Legionella longbeachae was not isolated from the same type of leaf mold that he used as potting soil. This is the first case of Legionella longbeachae pneumonia from whom the organism was isolated in Japan. 相似文献
78.
79.
Masaki Okazaki Tosihiro Hamada Hiroaki Fujii Osamu Kusudo Akio Mizobe Shuji Matsuzawa 《应用聚合物科学杂志》1995,58(12):2243-2249
The activated sludge that had been sufficiently cultivated with DMF-containing waste water was entrapped and immobilized in spherical poly(vinyl alcohol) (PVA) hydrogel particles. Features of numbers and distribution of bacteria in the resultant PVA gel were estimated. The DMF-decomposing bacteria named Bacillus cereus D-1 was isolated. Several morphological and physiological responses of the bacteria were revealed. Spherical PVA gel with the DMF-decomposing bacteria prepared through of freezing and thawing was tested for treatment of DMF-containing effluent. Test results have shown the ability of stable operation and maintenance at the same capacity of 1 kg/m3/day by both a basic study and a bench plant test. © 1995 John Wiley & Sons, Inc. 相似文献
80.
K Maeda M Ono Y Kawaguchi M Niikura K Okazaki N Yokoyama Y Tokiyoshi Y Tohya T Mikami 《Canadian Metallurgical Quarterly》1996,46(1-2):75-80
We constructed a recombinant baculovirus expressing feline herpesvirus type I (FHV-1) gD in insect cells (Sf9 cells). The expressed product was identified as FHV-1 gD by a panel of monoclonal antibodies specific for the FHV-1 gD, and had an apparent molecular mass of approximately 49 kDa, which was less than that of the authentic FHV-1 gD. When the FHV-1 gD protein were expressed in Sf9 cells and CRFK cells in the presence of tunicamycin, the FHV-1 gD exhibited a molecular mass of 41 kDa. It was shown that the gD protein was transported to the surface of recombinant virus-infected Sf9 cells when examined by membrane-immunofluorescence analysis, and that the gD expressed on the surface of Sf9 cells adsorbed feline erythrocytes. Mice inoculated with a lysate of Sf9 cells expressing FHV-1 gD induced antibodies with virus-neutralizing and hemagglutination-inhibition activities. Therefore, the expressed gD appears to be biologically authentic. These data suggested that recombinant FHV-1 gD produced in Sf9 cells may be a useful immunogen as a feline vaccine. 相似文献