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81.
Room-temperature ring oscillation at 19.6 ps/gate has been accomplished with SAINT FETs using bulk GaAs and implantation. These results have been obtained along with extrinsic resistance reduction and capacitance reduction by taking full advantage of the n+-gate spacing controllability. 相似文献
82.
Y. Zhang T. Yamane S. Saji J. Takahashi 《Metallurgical and Materials Transactions A》1994,25(5):1102-1104
Formerly Graduate Student, Graduate School of Engineering, Osaka University, Suita Osaka 565, Japan 相似文献
83.
84.
Onodera K. Tokumitsu M. Sugitani S. Yamane Y. Asai K. 《Electron Device Letters, IEEE》1988,9(8):417-418
GaAs MESFET's with a gate length as low as 0.2 μm have been successfully fabricated with Au/WSiN refractory metal gate n+-self-aligned ion-implantation technology. A very thin channel layer with high carrier concentration was realized with 10-keV ion implantation of Si and rapid thermal annealing. Low-energy implantation of the n+-contact regions was examined to reduce substrate leakage current. The 0.2-μm gate-length devices exhibited a maximum transconductance of 630 mS/mm and an intrinsic transconductance of 920 mS/mm at a threshold voltage of -0.14 V 相似文献
85.
T Nakagawa H Yamane M Takayama K Sunami Y Nakai 《Canadian Metallurgical Quarterly》1998,118(4):530-533
This study examines one of the largest pedigrees with radial polydactyly type IV (uncomplicated polysyndactyly) comprising a total of 69 individuals, of whom 26 have been affected over six generations. Typical manifestations of the pedigree were bilateral radial and ulnar digital duplications, as well as syndactyly between the middle and ring fingers and the second and third toes. There was no craniofacial anomaly in any of the 17 cases examined physically. This observation suggests that radial polydactyly type IV and Greig craniofacial-synostosis syndrome with similar digital manifestations are clinically-distinct entities. 相似文献
86.
K Yamane T Shima Y Okada M Nishida S Okita T Hatayama T Nishida 《Canadian Metallurgical Quarterly》1994,42(5):433-437
A rare case of primary pineal melanoma is reported. The patient was a 53-year-old woman who complained of a severe headache. Computed tomography and magnetic resonance images revealed obstructive hydrocephalus caused by a mass lesion in the pineal region. A biopsy was performed through an occipital transtentorial approach. A black pigmented solitary tumor was seen without leptomeningeal dissemination. Histologic examination revealed melanoma. Chemotherapy consisting of dacarbazine, ACNU, vincristine, and interferon was used. Follow-up imaging studies showed dramatic reduction of the tumor without recurrence for 4 years. This report demonstrates that a solitary primary intracranial melanoma without leptomeningeal dissemination and with rare mitoses may yield a good result with chemotherapy. 相似文献
87.
88.
Bistatic radar cross-section measurements by pendulum method 总被引:1,自引:0,他引:1
In this paper, the pendulum method for measuring the bistatic radar cross section of a target is proposed, based on the principle of modulated-scattering technique. A modulated wave is formed by swinging the target like a pendulum. This method has the advantages that the measuring procedure is very simple, an absorber-coated room is not required, and the measured value is independent of background waves. Theoretical aspects of the principle are first described, including various kinds of conditions; then the measuring method is given with experimental results. 相似文献
89.
Toshiyuki Hirano Masaharu Yamaguchi Toshimi Yamane 《Metallurgical and Materials Transactions B》1974,5(5):1249-1250
In the two phase alloys which exhibit superplasticity, strain rate sensitivitym, in the relationship σ =Kε
m, has been known to be strongly dependent on the volume fraction of the second phase. It, however, has not been necessarily
confirmed experimentally on various two phase alloys. In this paper we present an experimental evidence showing that the largestm is obtained when the volume fraction of the second phase is around 0.5. 相似文献
90.
Ricin A-chain is delivered into macrophages via receptor-mediated endocytosis. We have found that following uptake via the mannose receptor, ricin A-chain is rapidly cleaved by endosomal proteases. Inhibition of endosomal proteases such as cathepsin D and B leads to the accumulation of toxin inside the cell. Inhibition of cathepsin D reduces ricin A-chain cytotoxicity, while blocking cathepsin B enhances cytotoxicity. Similar results were obtained using fibroblasts transfected with the mannose receptor. Our data strongly suggest that the activation or membrane translocation of ricin A-chain is dependent upon the action of specific proteases. 相似文献