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排序方式: 共有233条查询结果,搜索用时 31 毫秒
121.
Kazuhiro Kajikawa Motoaki Nishimura Hiroyuki Moriyama Masataka Iwakuma Kazuo Funaki 《Electrical Engineering in Japan》2002,141(3):50-57
The influence of stacks of Bi‐2223 multifilamentary tape‐shaped wires without twisting on AC losses observed in an external magnetic field perpendicular to their wide faces is investigated. The perpendicular‐field losses decrease with increasing number of tapes in the range of small field amplitudes. At larger amplitudes, on the other hand, the AC losses have little dependence on the stack number. This can be attributed to the effect of magnetic interaction between wires. By taking into account effective demagnetization factors on the basis of theoretical consideration, the perpendicular‐field losses are plotted on a master curve for the maximum magnetic field applied to the wires. Furthermore, the perpendicular‐field losses measured as a function of the field amplitude are well reproduced by the numerical evaluation of AC losses for a slab with infinitely wide surfaces. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 141(3): 50–57, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10050 相似文献
122.
Masashi Tanaka Hiroyuki Sasakura Yoshiya Akagi Shigeki Tsukui Motoaki Adachi 《Journal of Superconductivity and Novel Magnetism》2011,24(5):1673-1676
We already reported on the synthesis of new Pb-based 1212 layered cuprates containing sulfur in the (Pb0.75S0.25)Sr2(Y,Ca)Cu2O
z
system. There none of the samples showed superconductivity until after annealing under high O2 pressure. More recently, we have discovered that the samples could be substituted by Ba for Sr up to x=0.6 in the composition of (Pb0.75S0.25)(Sr2−x
Ba
x
)(Y0.4Ca0.6) Cu2O
z
. Then if the Ba-substitution is performed for Sr, some of the almost-single phase samples are found to show resistivity drops
and magnetic anomalies without annealing under high O2 pressure. Among the samples, a sample with the nominal composition of (Pb0.75S0.25)(Sr1.5Ba0.5)(Y0.4Ca0.6) Cu2O
z
is found to show the highest onset temperatures of a resistivity drop at about 35 K and a magnetic anomaly at about 31.5
K. These are higher than the highest values for the superconducting Ba-free sample of (Pb0.75S0.25)Sr2 (Y0.4Ca0.6)Cu2O
z
which was annealed under high O2 pressure. 相似文献
123.
Chan Soo Kim Motoaki Adachi Kikuo Okuyama John H. Seinfeld 《Aerosol science and technology》2013,47(9):941-952
Effects of NO 2 on particle formation in SO 2 /H 2 O/Air mixtures by f -ray irradiation as a source of hydroxyl radicals are investigated to evaluate the contribution of homogeneous and ion-induced nucleation in the nanometer-sized aerosol particle generation. The total particle number concentration, the charged-particle fraction, and the electrical mobility distribution of particles and hydrated and solvated ions generated in NO 2 /SO 2 /H 2 O/Air mixtures were measured at NO 2 levels of 0-1.98 ppm, SO 2 levels of 0-3.87 ppm, and H 2 O levels of 6480-9889 ppm. Total particle number concen2 tration first tends to increase with increasing NO 2 concentration up to a certain NO 2 level and then decreases for NO 2 concentrations beyond this point. The charged-particle fraction, indicative of particle formation by ion-induced nucleation, tends to decrease with increasing NO 2 concentration, reaching a minimum value. The peak intensity of the electrical mobility distribution for particles significantly exceeded that in the absence of NO 2 at a relatively low concentration of NO 2 . The intensity decreased with increasing NO 2 concentration and fell below that in the absence of NO 2 . The results indicate that 2 opposing mechanisms that enhance and suppress the particle formation work simultaneously in NO 2 /SO 2 /H 2 O/Air mixtures, and the dominant mechanism depends on the NO 2 concentration. 相似文献
124.
Hiroyuki Sasakura Yoshiya Akagi Masashi Tanaka Shigeki Tsukui Motoaki Adachi 《Journal of Superconductivity and Novel Magnetism》2011,24(5):1485-1489
The Pb-based 1212 compounds containing phosphorus were already discovered by us in the (Pb,P)Sr2(Y,Ca)Cu2O
z
system. Among the almost-single phase samples, a sample with the nominal composition of (Pb0.75P0.25)Sr2(Y0.4Ca0.6)Cu2O
z
was a superconductor with the highest T
c of 38 K in the system. Recently, we have been investigating on substitution effect of Ba for Sr on superconductivity in the
(Pb0.75P0.25)(Sr2−x
Ba
x
)(Y0.4Ca0.6)Cu2O
z
system. As a result, it is found that the almost–single 1212 phase samples are obtained in the composition area of 0.0≤x≤0.4. In this area, with increase of x, the lattice parameters a,c and the cell volume V are found to be gradually increasing. This finding can be considered to show that larger Ba2+ ions certainly occupied the Sr-sites in the sample. However, we obtain such interesting results as that the T
c value is not so enhanced by the substitution in comparison with that of the sample of x=0.0, and that the maximum value of T
c was 40 K for x=0.2 and 0.3 at the best. 相似文献
125.
Hosaka S Koyabu H Noro M Takizawa K Sone H Yin Y 《Journal of nanoscience and nanotechnology》2010,10(7):4522-4527
Inclination atomic force microscope (AFM) imaging has been studied on the possibility to observe a pattern sidewall in contact mode or digital probing (step-in) mode for a line edge roughness (LER) or line width roughness (LWR). Analysis of the AFM tip bending and slipping indicates that it is serious problem to measure and control very fine patterns within an error of less than 1 nm in contact of the tip on the steep slop of the pattern, and it is very important directly to observe the sidewall at inclination angle. In experiments using pyramidal tip and steep Si pattern with about 90 degrees slop, it has demonstrated that the inclination angle is 35-40 degrees for faithful observation of the sidewall. We have observed the etched strip lines on the sidewall with a width of about 100 nm and a depth of about 6.4 nm. We have demonstrated that the inclination AFM is very useful for evaluation of the LER or LWR. 相似文献
126.
Hiroyuki Sasakura Yoshiya Akagi Shigeki Tsukui Motoaki Adachi 《Journal of Superconductivity and Novel Magnetism》2010,23(4):437-441
Possibility of boron substitution for Bi and the substitution effect on superconductivity is investigated for the Bi-2212 phase of Bi-Sr-Ca-Cu-O. From X-ray diffraction study, it is found that samples in the (Bi2?x B x )Sr2CaCu2O z system are mainly of the single 2212 phase in a composition range of 0.0≤x≤0.6, and both of the lattice parameters a and c change with increasing x up to 0.6. From measurements of the magnetic susceptibility and the electrical resistivity, the superconducting transition temperature is found to increase up to 0.6 with increasing x. These results are considered to show that boron is substitutable for Bi up to x=0.6 in the (Bi2?x B x )Sr2CaCu2O z system and that the boron substitution causes the number of hole-carriers to decrease in this system. 相似文献
127.
Hiroyuki Sasakura Yoshiya Akagi Shigeki Tsukui Motoaki Adachi 《Journal of Superconductivity and Novel Magnetism》2010,23(4):535-538
Possibility of boron substitution for Bi and the substitution effect on superconductivity is investigated for the Bi-2212
phase of Bi-Sr-Ca-Cu-O. From X-ray diffraction study, it is found that samples in the (Bi2−x
B
x
)Sr2CaCu2O
z
system are mainly of the single 2212 phase in a composition range of 0.0≤x≤0.6, and both of the lattice parameters a and c change with increasing x up to 0.6. From measurements of the magnetic susceptibility and the electrical resistivity, the superconducting transition
temperature is found to increase up to 0.6 with increasing x. These results are considered to show that boron is substitutable for Bi up to x=0.6 in the (Bi2−x
B
x
)Sr2CaCu2O
z
system and that the boron substitution causes the number of hole-carriers to decrease in this system. 相似文献
128.
Hiroyuki Sasakura Yoshiya Akagi Masashi Tanaka Shigeki Tsukui Motoaki Adachi 《Journal of Superconductivity and Novel Magnetism》2010,23(7):1381-1384
New Pb-based layered cuprates containing boron with the 1232 structure have been synthesized in the (Pb0.5B0.5)Sr2(Er3−x−y
Ce
x
Sr
y
)Cu2O
z
system. Nearly the single 1232 phase samples are obtained for the nominal composition of 1.6≤x≤1.9 and y=0.2. A sample with the composition of (Pb0.5B0.5)Sr2(Er1.2Ce1.6Sr0.2)Cu2O
z
shows resistivity-dropping phenomenon below 10 K and it shows a diamagnetic signal at about 9.0 K, though the superconducting
volume fraction is very small. From these results, the sample may well be a new Pb-based superconductor with the 1232 structure. 相似文献
129.
To satisfy a designer's intention for constructing aesthetic shapes such as automotive bodies, we propose a surface generation method. In the surface design process, designers determine shapes according to their great concern for the reflected images of vehicle surroundings, shade lines and highlight lines. Since reflection and shading are affected by changes of surface normal, the curvature variation of the surface, which represents the change of the surface normal, should be smooth and distributed as designers want. The proposed method controls curvature distribution directly by determining a surface shape from an evolute, which is a locus of the curvature center of the generatrix and moves along directrices to form the surface. It first generates evolutes of boundary curves to be generatrices as rational Bezier curves, then interpolates their shapes with the Bezier polygons, and locates the interpolated shape to the corresponding position of the directrices. By applying this method, we have confirmed that a smooth shape is generated from four boundary curves. 相似文献
130.