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41.
Bending tests of crystalline nanotubes composed of fullerene C60 molecules are performed inside a high-resolution transmission electron microscope. We fixed one side of a C60 nanotube with a body-centered tetragonal structure with typical inner and outer diameters, i.e., 180 nm and 510 nm, respectively, and then applied concentrated forces on the other side using piezomanipulation of a silicon nanotip. The bending process was observed in situ by transmission electron microscopy with simultaneous measurements of the forces by an optical deflection method. It was found that the Young’s modulus of the nanotube was estimated to be 62–107 GPa, which was 1.1–3.3 times larger than that of C60 nanowhiskers. The result concerning the increase in the Young’s modulus of the C60 nanotube provided an experimental evidence for the structural model composed of an inner core and a surface shell for C60 nanowhiskers. 相似文献
42.
Creep crack growth rates were measured using centrally cracked tension specimens of thin polypropylene film with different
crack lengths at various stresses and temperatures. The creep crack growth rates were correlated with the stress intensity
factor. There was the region of the minimum constant crack growth rate which occupied more than 70% of the total creep failure
life. This constant creep crack growth rate characteristics were analyzed on the basis of the stress-dependent Arrhenius type
thermally activated process. 相似文献
43.
Yasushi Sobajima Kunihiro Mori Masahiro Tsukamoto Norimitsu Yoshida Masao Takahashi Hikaru Kobayashi Shuichi Nonomura 《Solar Energy Materials & Solar Cells》2005,85(2):240-187
Effects of cyanide (CN) treatment with hydrogenated amorphous silicon (a-Si:H) films have been investigated. The decrease of ΔV/V was observed in cyanide treated a-Si:H films and the successive thermal annealing at 200°C after CN treatment induced the further reduction of the ΔV/V. XPS spectra show the indirect evidence that the cyanide species is present within 10 nm from the hydrogenated amorphous silicon surface. The results of CN treatment with a-Si:H solar cells are demonstrated. 相似文献
44.
Nakazawa Y. Komatsu T. Saito T. 《Vision, Image and Signal Processing, IEE Proceedings -》1996,143(4):234-240
The authors propose an image processing-based approach towards the development of a super-high-resolution image acquisition system. Imaging methods based on this approach can be classified into two main categories: a spatial integration imaging method and a temporal integration imaging method. With regard to the spatial integration imaging method, the authors have previously presented a method for acquiring an improved-resolution image by integrating multiple images taken simultaneously with multiple different cameras. They develop their work, aiming at a particular class of application where a user indicates a region of interest (ROI) on an observed image in advance, and apply a prototypal temporal integration imaging method. The prototypal temporal integration imaging method does not involve global image segmentation, but uses a subpixel registration algorithm which describes an image warp within the ROI, with subpixel accuracy, as a deformation of quadrilateral patches. The method then performs a subpixel registration by warping an observed image with the warping function recovered from the deformed quadrilateral patches. Experimental simulations demonstrate that the temporal integration imaging is promising as a basic means of high resolution imaging 相似文献
45.
T Saito S Kurumada Y Kawakami H Go T Uchiyama K Ueki 《Canadian Metallurgical Quarterly》1996,56(2):105-106
A modified surgical splint for Le Fort I osteotomies with transverse expansion is presented. The splint is made of a transpalatal stainless steel bar with acrylic abutment against the palatal surface of the molar and bicuspid tooth. It is rigid and renders excellent retention. It causes minimal patient discomfort, and oral hygiene is hardly compromised. 相似文献
46.
Araki K. Saito H. Yuasa N. Rei T. Itozaki H. Higaki K. 《IEEE transactions on magnetics》1992,28(3):1805-1809
Broadband measurements have been done on high T c superconducting coplanar lines of YBa2Cu3O 7 on [100]MgO substrates. From the transmission and reflection coefficients of coplanar lines, the characteristic impedance, attenuation constant, phase constant, group velocity, and London penetration depth of the film are derived, based on the circuit models 相似文献
47.
48.
49.
Polarization-controlled single-mode VCSEL 总被引:2,自引:0,他引:2
Yoshikawa T. Kawakami T. Saito H. Kosaka H. Kajita M. Kurihara K. Sugimoto Y. Kasahara K. 《Quantum Electronics, IEEE Journal of》1998,34(6):1009-1015
Relative intensity noise (RIN) in a vertical-cavity surface-emitting laser (VCSEL) was greatly reduced through the use of polarization control to eliminate competition between two orthogonal polarization states by ensuring there was only one polarization state. Polarization was stable with optical feedback of up to 10%. Polarization control was achieved by inducing a small loss anisotropy in fundamental transversal mode VCSEL's. Anisotropic post structures, such as a rectangular post, an oblique post, or a zigzag-sidewall post, were found to be effective in creating loss anisotropy without serious degradation of other VCSEL characteristics such as light-output power or beam profile 相似文献
50.
S Saito 《Canadian Metallurgical Quarterly》1993,76(2):427-431
This experiment was designed to examine the effect of silent mouthing on the phonological similarity effect. 16 undergraduates were tested for serial recall of visually presented letter sequences that were either phonologically similar or dissimilar. The letter sequences had to be remembered under two conditions, a control condition and a silent mouthing condition in which subjects had to articulate irrelevant words silently during the study period. Analysis showed the clear advantage of the dissimilar sequence over the similar one in the control condition. In contrast, this phonological similarity effect disappeared in the silent mouthing condition. This result is consistent with the working memory model. 相似文献