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61.
The discharge behaviour of electrodeposited lead dioxide and lead electrodes was investigated under various conditions; the surfaces of the discharged electrodes were observed with a scanning electron microscope. Both the positive and negative electrodes were passivated by a covering of deposited lead sulphate crystals. The amount of lead sulphate required for passivation depended on the size of the crystals. 相似文献
62.
AC Galloway SB Colvin EA Grossi MA Parish AT Culliford T Asai NM Rofsky JC Weinreb S Shapiro FG Baumann 《Canadian Metallurgical Quarterly》1993,105(5):781-8; discussion 788-90
During an 8-year period (1984 to 1991) 66 patients (mean age 59 years, range 26 to 84 years) with type A aortic dissection (60 ascending aorta tears, 6 arch tears; 35 acute, 31 chronic) had surgical repair by a continuous suture-graft inclusion technique. Hypothermic circulatory arrest (16 degrees C) was used in 58 patients (35/35 acute, 23/31 chronic; mean arrest time 26 minutes, range 10 to 55 minutes). Fifty-two patients had hemiarch repair and 6 had total arch replacement. Aortic valve disease necessitated treatment in 38 patients (1 valved conduit, 20 valve replacements, 17 valve repairs). Recently 11 patients had valve repair by reconstruction of the native aortic root, by means of techniques similar to those used for homograft valve insertion. Operative mortality was 9% (14% acute, 3% chronic). Stroke occurred in 2 patients (3%) and was fatal in both. Variables suggestive of increased operative risk by univariate analysis were acuteness (p = 0.12), visceral ischemia (p = 0.12), and preoperative shock (p = 0.13). No variable was significant by multivariate analysis. Overall actuarial survival at 48 months was 77%, with 3 late deaths from a ruptured distal aneurysm. Late computed tomography or magnetic resonance imaging scan was done in 28 patients at a mean interval of 33 months. These studies identified 1 patient with a pseudoaneurysm requiring reoperation and 3 patients with contained flow between the graft and the wrap. Three patients required late operation: 1 for pseudoaneurysm, 1 for arch dissection, and 1 for repair of a distal aneurysm. 相似文献
63.
T. Inagaki Y. Doi H. Hirabayashi Y. Kato K. Kawano H. Sato S. Sugimoto K. Takamatsu E. Takasaki T. Tsuru H. Yoshimura O. Asai T. Satow 《低温学》1984,24(2):83-89
Benkei, which was a large window frame conventional magnet at KEK has been converted to a superconducting magnet. In the conversion, the pole gap has been doubled from 0.5 m to 1.0 m retaining an analysing power at 2 T m. Several new techniques were applied to coil windings and cryostat fabrication. The superconducting Benkei has shown satisfactory performances for long term operation. 相似文献
64.
Quaternary AlGaInAs quantum-well optical modulators operating at 1.55 μm are introduced and demonstrated for the first time. An electron-to-heavy-hole exciton absorption peak shift of over 600 Å is observed for a bias voltage of 6 V. An extinction ratio of 19 dB and high-speed operation over 4 GHz is obtained for this optical modulator 相似文献
65.
The melting of Fe-Cr-Ni alloys under 200 MPa nitrogen pressure has shown that nitrogen significantly improves the mechanical properties. Tensile strengths of these high-nitrogen alloys were found to be proportional to interstitial nitrogen concentration. The tensile strengths of nitrogen-alloyed steels could be significantly increased over comparable carbon-alloyed steels. The increase in tensile strength was found to be proportional to the square root of the interstitial nitrogen concentration indicating that the strengthening may be controlled by thermal effects. 相似文献
66.
67.
T Inada T Sugita I Dobashi A Inagaki Y Kitao G Matsuda S Kato T Takano G Yagi M Asai 《Canadian Metallurgical Quarterly》1995,5(3):113-116
Cycads, the most primitive of the living gymnosperms, have been used and continue to be used for food and medicinal purposes by many cultures, although toxins must be removed before ingestion. In our quest to identify tropical plants that contain inhibitors of the cytochrome P-450 aromatase and thus may be efficacious in treating estrogen-dependent tumors, we have screened extracts from 5 species of cycad folia encompassing 3 genera: Cycas cairnsiana F. Muell., Cycas revoluta Thunb., Cycas rumphii Miq., Dioon spinulosum Dyer and Encephalartos ferox Bertol. All extracts were found to contain inhibitors of the human enzyme. 相似文献
68.
Two-dimensional statistical functions such as spectral density function, coherence function and phase angle are used to evaluate the single and joint segregation characteristics of alloying elements. Employing the latter two functions, the joint segregation index, defined elsewhere for a one-dimensional case, is redefined for a two-dimensional one. The effects of calcium treatment on center segregation (macrosegregation) and intergranular segregation (semi-macrosegregation) of MnS in three commercial calcium treated steel slabs, continuously cast under different operating conditions, are quantified by using the joint segregation index. The results are compared with those of a slab without calcium treatment. It is shown that both center segregation and intergranular segregation of MnS in all three calcium treated slabs are suppressed as compared with the slab without calcium treatment, and that the extent of the effect depends on the casting conditions. By reasoning on the basis of two-dimensional power spectra, it is shown that in a calcium treated slab sulfur and calcium are almost uniformly distributed throughout the slab, and that in the slab without calcium treatment sulfur and manganese appear together periodically only at largely spaced positions. 相似文献
69.
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
70.
N Mori Y Yatabe K Oka T Kinoshita T Kobayashi T Ono J Asai 《Canadian Metallurgical Quarterly》1996,149(2):699-705
Eight patients with nasal lymphoma in whom fresh-frozen tissues were available were studied to elucidate the nature of the lymphoma cells. Two cases were diagnosed as diffuse, large cell lymphoma, and the remaining six cases as diffuse, mixed cell types. Immunohistochemical studies revealed that all of the cases were positive for perforin, which is a specific marker for cytotoxic T or natural killer (NK) cells. As all of the cases were CD8 negative, the perforin-positive finding further confirmed the concept that nasal lymphoma is a distinct neoplastic entity derived from NK or NK-related cells. Light microscopic immunohistochemical studies revealed that these nasal lymphoma cases could be classified into Leu19(CD56)+Leu4(CD3)+ (two cases) and Leu19(CD56)+Leu4(CD3)- (six cases) types according to the phenotypes of the proliferating cells. However, simultaneous staining for perforin and Leu4 (CD3) using immunoelectron microscopy on the Leu19+Leu4+ cases showed that the perforin-positive cells were different from the Leu4-positive cells. This finding suggests that the Leu4-positive cells are not neoplastic NK cells but reactive T cells. Six cases were positive for EBER-1 by in situ hybridization analysis. This finding reconfirms the previous studies that Epstein-Barr virus plays a significant role in the pathogenesis of nasal lymphoma. 相似文献