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排序方式: 共有415条查询结果,搜索用时 15 毫秒
11.
Seong-Youl Bae Du-Hyon Cho Hee-Taik Kim Hidehiro Kumazawa 《Korean Journal of Chemical Engineering》1994,11(2):127-130
Sorption equilibria and permeation rates for oxygen and carbon dioxide in polycarbonate membrane were measured at different
temperature between 30 and 60°C and at pressures up to 2.5 MPa. The pressure dependence of mean permeability coefficient to
oxygen obeyed the conventional dual-mode mobility model, whereas that to carbon dioxide followed a modified dual-mode mobility
model with concentration-dependent diffusivities, as that of polystyrene to the same gas did. 相似文献
12.
Changes in the liquid hold-up, ?, and the diameter of d, of a foam that are induced by perforated plates (PPs) and the contribution of PPs to foam-breaking were studied. A foaming system containing a dilute detergent solution in a column with mechanical agitation fitted with a rotating-disk foam-breaker (MFRD) was used. After the foam passed through the PPs, ? and d decreased and increased, respectively. The use of PPs to achieve a maximum reduction in ? and a maximum increase in d is confirmed. It is also demonstrated that use of PPs contributes not only to improving the foam-breaking performance of the MFRD, but also to power savings. 相似文献
13.
To help corporations survive amidst worldwide quality competition, the authors have focused on the strategic development of a higher-cycled product design CAE model employing a highly reliable CAE analysis technology component model. Their efforts are part of principle-based research aimed at evolving product design and CAE development processes to ensure better quality assurance. To satisfy the requirements of developing and producing high quality products while also reducing costs and shortening development times, the effectiveness of this model was verified by successfully applying it to the technological problems of loosening bolts and other product design bottlenecks at auto manufacturers. 相似文献
14.
Clinicopathological significance of intratubular giant macrophages in progressive glomerulonephritis
T Oda O Hotta Y Taguma H Kitamura H Sugai S Onodera I Horigome K Suzuki Y Shouji T Furuta S Chiba N Yoshizawa H Nagura 《Canadian Metallurgical Quarterly》1998,53(5):1190-1200
Very large macrophages, which we have termed "giant macrophages" (G-M phi), have been found in renal tubules, some containing cytoplasmic vacuoles. To elucidate their pathophysiological roles, we examined renal biopsy tissues from various primary glomerulonephritis (GN) and tubulointerstitial nephritis (TIN) using immunohistochemistry with monoclonal antibodies against M phi and other cell surface markers. Giant macrophages were absent or rare in TIN, minimal change nephrotic syndrome, and minor glomerular abnormalities, but G-M phi was plentiful in progressive glomerulonephrides such as IgA nephropathy with crescents, membranoproliferative GN, focal segmental glomerulosclerosis, and especially in crescentic GN. These G-M phi were usually seen in the lumen of renal tubules, but occasionally were found in the Bowman's spaces and glomerular tufts, and similar cells were also found in urine. Moreover, they frequently made contact with tubular epithelial cells expressing intercellular adhesion molecule-1, and the tubular epithelial cells in such lesions often had degenerative changes. Giant M phi may damage tubular epithelial cells from the luminal side. Phenotypically, G-M phi showed activated (CD71+) and mature (25F9+) characteristics along with features of M phi (CD68+), and the cytoplasm contained a great deal of lipids. The numbers of G-M phi in renal tissues closely correlated with the degree of hematuria (rho = 0.5, P < 0.001), serum creatinine value (r = 0.63, P < 0.001) in GN patients (N = 96) and with proteinuria in IgA nephropathy patients (r = 0.89, P < 0.001, N = 27). These data suggest that G-M phi are M phi that were activated and matured in certain active inflammatory sites, which flowed into tubules and then into urine. Thus, the existence of G-M phi in biopsy tissue or urine reflect the activity of GN and may have a predictive value for the progression of GN. 相似文献
15.
Kusaka T Ueno M Miki T Kanenishi K Nagai Y Huang CL Okamoto Y Ogawa T Onodera M Itoh S Akiguchi I Sakamoto H 《Microscopy research and technique》2007,70(7):648-655
We investigated whether beta-amyloid (Abeta)-like immunoreactivity was seen in the brains of newborn piglets. The immunoreactivity for Abeta(1-42) and Abeta(1-40) proteins, but not Abeta precursor protein, was present in CD68-positive perivascular cells of the hippocampus and in parts of the meninges. It was colocalized with immunoreactivity for receptor for advanced glycation end product and tumor necrosis factor-alpha. The protein with a molecular mass of 27 kDa, which was recognized by the Abeta antibodies, was identified as triosephosphate isomerase (TPI) with sequence homology to Abeta peptides by N-terminal amino acid sequencing, mass fingerprint analysis using matrix-associated laser desorption/ionization mass spectrometry, and Western blotting. Western blotting assay also revealed that detectable expression of Abeta proteins were not seen in the piglet brains. These findings indicate that TPI with sequence homology to Abeta peptides accumulates in perivascular cells of the microglia/macrophage lineage located around arterial vessels of the newborn piglet hippocampus. 相似文献
16.
We investigate the static and dynamic behavior of vortices in a pin-free superconductor. A diffraction pattern is observed in the critical currentJ
cvs. applied fieldH
parallel to the surface of a granular Al film. When one vortex chain is formed in the film,J
cbecomes nearly equal to zero, which verifies that the sample is actually pin-free. An interaction between a radiofrequency current and moving vortices occurs, and theI–V curve shows peculiar nonlinear effects such as real negative resistance. The results are analogous to dc and ac Josephson effects. 相似文献
17.
A simple method of measuring refractive indices of bulk materials using a prism coupling procedure is described. Refractive indices are determined from the measurement of the angle incident to the prism at which total reflection on the prism base breaks. This method is shown to possess the advantages of its simple procedure and sample preparation. The accuracy is comparable with that of minimum deviation method if the prism is well calibrated. Experimental results for several materials are given with an evaluation of possible errors. 相似文献
18.
Hajime Masukawa Hidehiro Sakurai Robert P. Hausinger Kazuhito Inoue 《International Journal of Hydrogen Energy》2014
Heterocyst-forming cells of the cyanobacterium Anabaena sp. strain PCC 7120 ΔHup, lacking an uptake hydrogenase, photobiologically produce H2 by nitrogenase. Under N2-rich atmosphere, the nitrogenase activity declines in a rather short time due to the sufficiency of combined nitrogen. From the parental ΔHup strain, site-directed double-crossover variants, dc-Q193S and dc-R284H, were created with amino acid substitutions presumed to be located in the vicinity of the FeMo-cofactor of nitrogenase. Unlike the case for the ΔHup strain, H2 production activities of the variants were not decreased by the presence of high concentrations of N2 and they continuously produced H2 over 21 days with occasional headspace gas replacement. This property of N2 insensitivity is a potentially useful strategy for reducing the cost of the culture gas in future practical applications of sustainable biofuel production. This Anabaena strain has only the Mo-containing nitrogenase which reduces acetylene to ethylene, but the dc-Q193S variant also produced ethane at low but measurable rates along with greater rates of ethylene production. 相似文献
19.
20.
Clotilde Minfray Thierry Le Mogne Jean-Michel Martin Tasuku Onodera Sayaka Nara Shuko Takahashi 《摩擦学汇刊》2013,56(5):589-601
Zinc phosphate glass is considered to be the main constituent of tribofilms generated under boundary lubrication with zinc dialkyldithiophosphate (ZDDP), a well-known antiwear additive. The reaction occurring during friction between zinc phosphate glasses and steel native iron oxide layer is investigated by both an experimental approach and by Molecular Dynamics simulations (MD). The importance of this “tribochemical” reaction in the general ZDDP antiwear process is discussed. 相似文献