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排序方式: 共有404条查询结果,搜索用时 31 毫秒
31.
T Ichikawa Y Nakajima H Fujimoto A Koyama M Honma M Yatsuzuka K Ohtomo G Uchiyama S Ushigome S Ohba 《Canadian Metallurgical Quarterly》1997,26(10):602-605
We present a case of giant calcifying epithelioma of Malherbe (pilomatrixoma) in the right upper arm of a 62-year-old man. It measured 18 x 12 x 8 cm in size, making it the largest of all the cases reported previously. CT clearly demonstrated a well-defined, subcutaneous mass with amorphous calcifications. The mass showed intermediate signal intensity on T2*-weighted MR images and slight contrast uptake on contrast-enhanced MR images. Histopathologically, this tumor showed no aggressive or malignant nature. The patient is without evidence of recurrence or metastasis 3 years following the resection. 相似文献
32.
M Kohsaka N Fukuda R Kobayashi H Honma S Sakakibara E Koyama O Nakano H Matsubara 《Canadian Metallurgical Quarterly》1998,52(2):252-253
Subjective sleep feelings and motor activity were measured in seven healthy elderly subjects for 6 days. The subjects were exposed to bright light (6000 lux) for 30 min in the morning or instructed to sit in front of a desktop lighting device without light. The average level of motor activity during the night was significantly decreased in the bright light condition, compared with the controlled condition. However, daytime motor activity did not show significant differences between the two conditions. From these findings, even a short duration of morning bright light is effective in maintaining sleep without changing daytime activity. 相似文献
33.
Iwasaki K. Sato K. Aoyama K. Numao S. Honma I. Sugano S. Hoshina T. Sato T. 《Semiconductor Manufacturing, IEEE Transactions on》2003,16(3):360-364
6-in diameter Fe-doped semi-insulating InP single crystals have been grown by the hot-wall liquid encapsulated Czochralski method. This method has a quartz inner vessel to stabilize the thermal convection. Temperature gradient and solid-liquid interface shape can be controlled by a multizone heater system. The weight of grown crystal was 18 kg and the full length was 250 mm. The dislocation density was about 1/spl times/10/sup 5/ cm/sup -2/. The resistivity was more than 1/spl times/10/sup 7/ /spl Omega/cm and its uniformity was the same as the smaller diameter crystal. The conditions of wafer processing were optimized to improve the wafer flatness. The rolloff and the slope of the wafer surface could be reduced especially by the improvement of the polishing conditions. The typical total thickness variation was 3.3 /spl mu/m, and it was comparable to the GaAs wafer. 相似文献
34.
Seki T. Honma N. Nishikawa K. Tsunekawa K. 《Microwave and Wireless Components Letters, IEEE》2005,15(5):339-341
This letter describes a compact and high-gain multilayer parasitic microstrip array antenna (MPMAA). The design and performance of the proposed array antenna are presented. The antenna employs three layers with a 2/spl times/2 parasitic array on each layer. The developed prototype MPMAA employs a multilayer low-temperature co-fired ceramic (LTCC) substrate that is well suited to the assembly of MMIC chips. The fabricated MPMAA achieves a 7.17 dBi absolute gain at 60 GHz including the loss derived from the feeding parts and RF probe to measure its antenna performance. The spacing of the top layer of the parasitic array constructed by 2/spl times/2 elements has a free-space wavelength of 0.36 and the chip size is 10 mm/sup 2/. The fabricated MPMAA achieves both compact and high directional gain and satisfies the requirements for a millimeter-wave system-on-package (SOP). 相似文献
35.
Hirayama K. Honma Y. Hayashi Y. Koshiba M. 《Photonics Technology Letters, IEEE》1998,10(10):1359-1361
A novel finite-element formulation for the analysis of the energy levels of a two-dimensional quantum cavity in a magnetic field is proposed. Our formulation is based on both a variational and Galerkin methods which, when combined with a finite-element method, lead to eigenvalue problems characterized by either real or Hermitian matrices contrary to algorithms proposed in the past. These eigenvalue problems can then be solved quite efficiently on a computer using standard library packages. Also, it is confirmed that the results obtained here are independent of the choice of gauge 相似文献
36.
37.
K. Honma K. Hirota O. Yamaguchi J. Asai Y. Makiyama 《Journal of Materials Science Letters》1997,16(13):1195-1197
Abstracts are not published in this journal
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
38.
Highly Oriented Polymer Semiconductor Films Compressed at the Surface of Ionic Liquids for High‐Performance Polymeric Organic Field‐Effect Transistors
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40.
Spinel lithium titanate, Li4Ti5O12, with novel hollow-sphere structure was fabricated by a sol–gel process using carbon sphere as template. The effect of the hollow-sphere structure as well as the wall thickness on the Li storage capability and high rate performance was electrochemically evaluated. High specific capacity, especially better high rate performance was achieved with this Li4Ti5O12 hollow-sphere electrode material with thin wall thickness. It is believed that this macroporous hollow-sphere structure has shortened the Li diffusion distance, increased the contact area between Li4Ti5O12 and electrolyte, and also led to better mixing of the active material with AB. All these factors have resulted in the good rate capability of the hollow-sphere structured Li4Ti5O12 electrode material. 相似文献