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排序方式: 共有3157条查询结果,搜索用时 78 毫秒
31.
M Ogawa T Yamaguchi A Setiyono T Ho H Matsuda S Furusawa H Fukushi K Hirai 《Canadian Metallurgical Quarterly》1998,143(12):2327-2341
A flow cytometric virus binding assay that directly visualizes the binding of infectious bursal disease virus (IBDV) to its target cells was established. The chicken B lymphoblastoid cell line, LSCC-BK3, which is permissive for IBDV infection, bound high levels of the virus. Another B lymphoblastoid cell line, LSCC-1104-B1, bound low levels of the virus, although it was nonpermissive. No virus binding was detected in nonpermissive T lymphoblastoid cell lines. In the binding assay to heterogeneous cell populations of chicken lymphocytes, IBDV (a highly virulent OKYM strain) bound to 94% cells in the lymphocytes prepared from the bursa of Fabricius, 37% cells in those prepared from the spleen, 3% cells in those prepared from the thymus, and 21% cells in those prepared from the blood. Most of the cells, which bound the virus, were surface immunoglobulin M (SIgM)-positive, but a small number of them were SIgM-negative. Additionally, the binding of IBDV to the LSCC-BK3 cells was affected by treatment of the cells with proteases and N-glycosylation inhibitors. These findings may indicate that the IBDV host range is mainly controlled by the presence of a virus receptor composed of N-glycosylated protein associated with the subtle differentiation stage of B-lymphocytes represented mostly by SIgM-bearing cells. 相似文献
32.
Eliichi Yamaguchi 《AI & Society》1990,4(2):147-154
In this paper I consider how the computer can or should be accepted in Japanese schools. The concept of teaching in Japan stresses learning from a long-term perspective. Whereas in the instructional technology, on which the CAI or the Tutoring System depends, step-by-step attainments in relatively short time are emphasized. The former is reluctant in using the computer, but both share the Platonic perspective which are goal-oriented. However, The Socratic teacher, who intends to activate students' innate disposition to be better, would find another way of teaching and use of the computer. 相似文献
33.
Rod-shaped BaTiO3 powder particles have been prepared from rod-shaped TiO2 ·nH2O and BaCO3 in molten chloride. The morphology of BaTiO3 particles was studied referring to the effects of the chemical species of the starting titanium compound, amount of chloride, particle size of the titanium compound and reaction conditions, and the preparation condition of rod-shaped BaTiO3 has been determined: i.e., large TiO2 ·nH2O particles were heated at 700°C in molten salt with an equal amount of BaTiO3. This condition was effective in suppressing the formation of BaTiO3 by a solution-precipitation process as well as the deformation of either TiO2 ·nH2O or BaTiO3, which are responsible for the formation of equiaxed BaTiO3 particles. The obtained rod-shaped BaTiO3 particles had a cubic symmetry. Electron diffraction analysis showed that the following topotactic relation is retained; 0 1 0potassium tetratitanate 0 1 0hydrated titania 1 0 0anatase 1 0 0barium titanate 相似文献
34.
A study has been made of ‘combined’ joints consisting of mechanical fastening and adhesive bonding between rigid adherends. The mechanical characteristics of such ‘hybrid’ butt and lap shear joints have been derived by theoretical analysis. Results from experimental tests in combined joints giver reasonable agreement with the theoretical equations relating joint load to deformation. 相似文献
35.
Kikuo Maekawa Makoto Yamazaki Toshinobu Ogiso Takehiko Maruyama Hideki Ogura Wakako Kashino Hanae Koiso Masaya Yamaguchi Makiro Tanaka Yasuharu Den 《Language Resources and Evaluation》2014,48(2):345-371
The balanced corpus of contemporary written Japanese (BCCWJ) is Japan’s first 100 million words balanced corpus. It consists of three subcorpora (publication subcorpus, library subcorpus, and special-purpose subcorpus) and covers a wide range of text registers including books in general, magazines, newspapers, governmental white papers, best-selling books, an internet bulletin-board, a blog, school textbooks, minutes of the national diet, publicity newsletters of local governments, laws, and poetry verses. A random sampling technique is utilized whenever possible in order to maximize the representativeness of the corpus. The corpus is annotated in terms of dual POS analysis, document structure, and bibliographical information. The BCCWJ is currently accessible in three different ways including Chunagon a web-based interface to the dual POS analysis data. Lastly, results of some pilot evaluation of the corpus with respect to the textual diversity are reported. The analyses include POS distribution, word-class distribution, entropy of orthography, sentence length, and variation of the adjective predicate. High textual diversity is observed in all these analyses. 相似文献
36.
S. Yamaguchi Y. W. Leong T. Tsujii M. Mizoguchi U. S. Ishiaku H. Hamada 《应用聚合物科学杂志》2005,98(1):294-301
A previous study has shown that the adhesion between the film and substrate of film‐insert injection‐molded poly(propylene) (PP) film/PP substrate was evident with the increases in barrel temperature and injection holding pressure. In this second part of the research work, the crystallinity at the interfacial region (i.e., region between the film and the injected substrate) was extensively studied using FTIR imaging, polarized light microscopy, and DSC in an attempt to determine the level of influence that crystallinity has on the interface and bulk mechanical properties. Consequently, a more thorough and clearer picture of the influence of the inserted film on the interfacial crystallinity and subsequently the substrate mechanical properties, such as peel strength and impact strength, has been revealed. The initial proposition that crystallinity could enhance film–substrate interfacial bonding has been confirmed, judging from the higher peel strength with increasing crystallinity at the interfacial region. Nevertheless, the change in crystallinity was not only confined to the interfacial region. With the film acting as heat‐transfer inhibitor between the injected resin and the mold wall, the total crystal structure of the substrate was substantially altered, which subsequently affected the bulk mechanical properties. The lower impact strength of film‐insert injection‐molded samples compared to that of samples without film inserts provided evidence of how the film could impart inferior properties to the substrate. The difference in cooling rate between the substrate and film might also cause other defects such as warpage and/or residual stress build‐up within the product. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 294–301, 2005 相似文献
37.
Shingo Hirano Masaru Yoshinaka Ken Hirota Osamu Yamaguchi 《Journal of the American Ceramic Society》1996,79(1):171-176
In the ZrO2 -Cr2 O3 system, metastable t -ZrO2 solid solutions containing up to 11 mol% Cr2 O3 crystallize at low temperatures from amorphous materials prepared by the hydrazine method. The lattice parameter c decreases linearly from 0.5149 to 0.5077 nm with increased Cr2 O3 content, whereas the lattice parameter a is a constant value ( a = 0.5077 nm) regardless of the starting composition. At higher temperatures, transformation (decomposition) of the solid solutions proceeds in the following way: t (ss)→ t (ss) + m + Cr2 O3 → m + Cr2 O3 . Above 11 mol% Cr2 O3 addition, c-ZrO2 phases are formed in the presence of Cr2 O3 . The t -ZrO2 solid solution powders have been characterized for particle size, shape, and surface area. They consist of very fine particles (15–30 nm) showing thin platelike morphology. Dense ZrO2 (3Y)-Cr2 O3 composite ceramics (∼99.7% of theoretical) with an average grain size of 0.3 μm have been fabricated by hot isostatic pressing for 2 h at 1400°C and 196 MPa. Their fracture toughness increases with increased Cr2 O3 content. The highest K Ic value of 9.5 MPa·;m1/2 is achieved in the composite ceramics containing 10 mol% Cr2 O3 . 相似文献
38.
Y. Nakama Y. Shiojima Y. Takeshita M. Yamaguchi 《Journal of the American Oil Chemists' Society》1997,74(7):803-808
The formation of a complex, composed of lauroamphoglycinate (LG), oleic acid (OA) and water, was investigated, and this system
was applied to emulsification. The complex was formed in the water-rich area (more than 90% in this system) at a molar ratio
of OA to LG from 1 to 3, where two-phase systems of water and the complex existed. The interaction between LG and OA, both
in the aqueous solution and at the interface of liquid paraffin dissolving the OA and LG solution, was studied by pH measurements
and interfacial tension measurements, respectively. The results implied that LG and OA were linked stoichiometrically, both
in aqueous solution and at the interface, and formed complexes. X-ray diffraction patterns and the strong hydrophobicity showed
that the equimolar complex composed of LG, OA, and water was a liquid crystal with a reversed hexagonal structure. The reversed
hexagonal liquid crystal was capable of solubilizing a certain amount of liquid paraffin in its alkyl group parts while maintaining
its hexagonal structure. These results suggest the possibility to prepare a W/O-type emulsion by using the liquid crystal
formed by LG, OA, partial liquid paraffin, and water as the continuous phase. The authors could obtain a stable W/O emulsion
without coalescence of the water droplets that contained a substantial amount of water (approximately 90%). Furthermore, various
types of emulsions, O/W, W/O, W/O/W, could be prepared by changing the ratio of LG and OA. 相似文献
39.
The formation of lead tantalates in the PbO-rich region is studied using the powders prepared by the simultaneous hydrolysis of lead and tantalum alkoxides. Cubic 3PbO · 2Ta2O5 solid solutions crystallize at low temperatures from amorphous materials between 60 and 75 mol% PbO. The lattice parameter,a, increases linearly from 1.0545 to 1.0705 nm with increasing PbO. At higher temperatures the solid solutions above 66.67 mol% PbO are transformed into those of rhombohedral 2PbO · Ta2O5. Rhombohedral 5PbO · 2Ta2O5 is formed at 850 to 900 °C by transformation of 2PbO·Ta2O5 solid solution corresponding to 71.43 mol% PbO. The existence of previously reported 3PbO·Ta2O5 is not confirmed. 相似文献
40.
Titanium carbide nano-fiber was synthesized by self-propagating high temperature synthesis (SHS) method. The final products
after the SHS reaction were titanium carbide containing excess carbon and metallic titanium, which were removed by additional
leaching process. TEM observation revealed that the average diameter is about 20 nm. Neutron diffraction analysis was carried
out to study non-stoichiometric number of the titanium carbide. The non-stoichiometric numbers of the titanium carbide were
0.89–0.94. The Rietveld refinement of each patterns converged to good agreement (÷2=0.49–1.34). The formation mechanism of
the carbide is related to a liquid-solid reaction including the preferential diffusion process of carbon atom into liquid
titanium.
This article is based on a presentation made in the 2002 Korea-US symposium on the “Phase Transformations of Nano-Materials,”
organized as a special program of the 2002 Annual Meeting of the Korean Institute of Metals and Materials, held at Yonsei
University, Seoul, Korea on October 25–26, 2002. 相似文献