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31.
When zinc oxide and graphite were placed into an alumina crucible, with a square hole (∼3 mm ×∼3 mm) near the top, and the crucible was covered by an alumina lid and heated at >1050°C, a hollow polycrystal composed of needlelike, ribbon(comb)-like, dendritic, and bulk zinc oxide crystals grew from the hole toward the outside of the crucible. The diameter and length of the polycrystal grown at 1050°C after 1 h were ∼2.2 mm and ∼20 cm, respectively. The diameter increased, while the length decreased, with increasing temperature. Most of the needlelike zinc oxide crystals in the hollow polycrystal were elongated along the c -axis. 相似文献
32.
33.
K Hashimoto S Prada AP Lopez JG Hoyos M Escobar 《Canadian Metallurgical Quarterly》1998,15(5):360-366
The traditional rhomboid transposition flap has been widely used in reconstructive surgery. The authors have modified the original technique by eliminating the creation of the rhomboid defect and by directly transposing the flap into the original postexcisional defect. These changes allow maximum flexibility in flap design and minimize normal tissue loss. The authors retrospectively reviewed the charts of patients who underwent periocular reconstruction with flaps from 1990 through 1995. The authors selected those patients in whom the modified rhomboid flap was used. Functional and cosmetic results and complications were reviewed. Two hundred thirty-two patients were identified in whom 242 flaps were performed. The modified rhomboid flap was used in 101 patients (41.7%). Complications occurred in 23 patients (23%), 19 of whom (19%) were treated medically and four of whom (4%) required an additional surgical procedure. Cosmetic and functional results were classified as very good or excellent in 96 patients (96%). The use of a modified rhomboid flap in the reconstruction of the periocular area offers ample versatility in flap design and minimal normal tissue loss. Functional and cosmetic results are satisfactory in the vast majority of cases. 相似文献
34.
Y Mazaki H Uchida O Hino S Hashimoto H Sabe 《Canadian Metallurgical Quarterly》1998,273(35):22435-22441
Paxillin, a focal adhesion protein, exists as multiple isoforms in humans (alpha, beta, and gamma). To understand more about the physiological role of each isoform, we have employed the mouse system. We found that although the alpha and beta isoforms are present in the mouse, the gamma isoform is not. The alpha isoform protein was detected clearly in most adult tissues, whereas the beta isoform protein was almost undetectable except in spleen, testis, thymus, and lung. On the other hand, mRNAs of both isoforms were detectable in all tissues we examined. High levels of the beta isoform protein was detected in peritoneal exudate macrophage cells in adult mouse as well as in cultured fibroblasts, together with the alpha isoform. The alpha isoform was expressed at a constant level throughout the embryonic stages we examined, whereas the beta isoform protein was detected at the mid-stages of development and increased to levels almost equal to those of the alpha isoform during the late stages of embryogenesis. Therefore, unlike the alpha isoform, expression of the beta isoform protein is restricted in adult tissues. Moreover, we showed that alpha and beta isoforms were colocalized within the same focal adhesion plaques, and cytoplasmic pools of both isoforms exist in the perinuclear area, colocalized with the Golgi apparatus. 相似文献
35.
H Miyachi Y Koiso R Shirai S Niwayama JO Liu Y Hashimoto 《Canadian Metallurgical Quarterly》1998,46(7):1165-1168
The synthesis and tumor necrosis factor (TNF)-alpha production enhancing activity of substituted 3'-methylthalidomides on human leukemia cell line HL-60 stimulated with 12-O-tetradecanoyl-phorbol 13-acetate (TPA) are described. Though the introduction of an electron-donating amino group at the phthaloyl moiety of alpha-methylthalidomides enhanced the activity, substituted alpha-methylthalidomides showed decreased stereoselectivity as compared to that of non-substituted alpha-methylthalidomide. The data indicates that the TNF-alpha production enhancing activity of thalidomide derivatives depends on both the electronic-state of substituents at the fused benzene ring and the stereochemistry of the glutarimide moiety. 相似文献
36.
37.
Tomotaka Hashimoto Nobuo Ishizawa Nobuyasu Mizutani Masanori Kato 《Journal of Materials Science》1988,23(3):1102-1105
The temperature dependence of the electrical resistivity and Seebeck coefficient was measured on single crystals of La1–x
Ca
x
MnO3(0 <x 0.3) and La1–x
Sr
x
MnO 3 (0 <x 0.4) grown by the arc-image floating zone method. The electrical conduction for La1–x
crystals withx 0.2 was of the activation type aboveT
c and of the degenerate type belowT
c, while that for the crystal withx = 0.1 was of the activation type over the whole measured temperature range between –170 and 400°C. The conduction behaviour of La1–
x
Sr
x
MnO3 was essentially the same as that of La1–x
Ca
x
MnO3 except that the conduction of the crystals withx = 0.3 and 0.4 was of the degenerate type aboveT
c. A distinct difference in Seebeck data was observed between the calcium and the strontium compounds. 相似文献
38.
Compositions of surface films formed on nickel and Alloy 600 in I M HCI, 0.5 M H2SO4 and I/3 M H3PO1 solutions were investigated as a function of polarization potential. The main constituent of surface films formed on Ni in 0.5 M H2SO4 or 1/3 M H3PO4 solution was hydrated nickel oxyhydroxide, in which the ratio of O2 to OH− increased when passivation occurred. The surface films formed on Ni and Alloy 600 at lower potentials in 0.5 M H2SO4 solution contain S2 ions other than SOP42− ions, whereas S2− ions were not incorporated in the passive film. Passivation of Alloy 600 took place by the formation of hydrated chromium oxyhydroxide. Pitting led to no substantial change in the average composition of the film. 相似文献
39.
Importance of initial surface film in the degradation of stainless steels by atmospheric exposure 总被引:1,自引:0,他引:1
The surface compositions of stainless steels types 304, 316, 430, and 444 combined with four types of surface finishes, 2B finish, hairline polishing, mirror polishing, and bright annealing, were measured by ICP-AES, EPMA, and XPS before exposure. The surface finish that most enriched the chromic species in the surface film was mirror polishing, followed by bright annealing, 2B finish, and hairline polishing. The order of corrosion-resistance was type 444, type 316, type 304, and type 430. The surface compositions were correlated with the rating number and pitting depth after exposure to atmospheric environments. The rating number had a high positive correlation with the concentration of Cr in the surface film, and had a slight correlation with the near-surface composition measured by EPMA at 12 kV, but did not show any correlation with bulk composition within the composition range covered in the present work. This same trend was observed for pitting depth. It was concluded that the cationic concentration of Cr in the surface film before atmospheric exposure is the prime factor in controlling the resistance of stainless steels to atmospheric corrosion. 相似文献
40.
The NMR spectra of olefinic protons in the four representative conjugated fatty acid methyl esters, methylcis-9,trans-11-octadecadienoate, methyltrans-9,trans-11-octadecadienoate, methyl α eleostearate, and methyl β eleostearate, were studied. The chemical shift of each olefinic
proton in these compounds was determined by considering their intramolecular environment. Coupling constants were also obtained
as the results of spectral analysis. 相似文献