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Temporal power spectra of the speckle signal detected by a simple optical fiber probe are analyzed as a function of the laser spot size at a moving scatter plate, the velocity of the plate, the core diameter of the detecting fiber and the numerical aperture of it. The fiber probe is shown to be useful for velocity measurements of the moving scatter plate. 相似文献
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Kunihiko Nakayama Ken-ichi Fukatsu Kazunori Maruyama Kouji Ogawa Tadashi Hasegawa Toshimasa Morohashi Nobuyuki Fujii 《Analytical sciences》2002,18(8):907-911
Gaseous monochlorobenzene was irradiated with KrF excimer laser (248 nm) under reduced pressure. The photodecomposition was an apparent first order reaction. When the system contained no additive gas, the photolysis was found to give benzene (conversion yield: 49%) in the gas phase and many unidentified products in the solid phase. On the other hand, in the presence of oxygen, carbon dioxide (10%), carbon monoxide (16%), hydrogen chloride (52%) and acetylene (2%) are produced and the peaks shown on the gas chromatogram of the solid phase were effectively suppressed. 相似文献
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A new technique is developed to visualize the blood flow map of the human retina using laser speckle phenomena. Despite use of an ordinary CCD camera as the detector, the performance of laser speckle flowgraphy system for the analysis of ocular blood circulation is greatly improved to achieve higher resolution and a wider field of view for blood flow mapping. It is shown that the quality of the blood flow map is influenced by the sampling format of the pixel points in the space- and time-varying speckle field. 相似文献
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Fabrication of p-Si/β-FeSi2 balls/n-si structures by MBE and their electrical and optical properties
T. Suemasu T. Fujii M. Tanaka K. Takakura Y. Iikura F. Hasegawa 《Journal of luminescence》1998,80(1-4):473-477
We report on the formation technique of single-crystalline β-FeSi2 balls (<100 nm) embedded in a Si p–n junction region by Si molecular beam epitaxy (MBE). β-FeSi2 films grown on Si (0 0 1) by reactive deposition epitaxy (RDE) aggregated into islands after annealing at 850°C in ultrahigh vacuum. The islands of β-FeSi2 aggregated further into a ball shape by following the Si MBE overgrowth at 750°C. It was found from X-ray diffraction (XRD) patterns that the epitaxial relationship between the two materials, and single-crystalline nature were preserved even after the annealing and the Si overgrowth. Capacitance–voltage (C–V) characteristics and transmission electron microscope (TEM) images revealed that a lot of defects were introduced around the embedded β-FeSi2 balls with an increase of embedded β-FeSi2 quantity. 相似文献
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Kimio Oguchi Tetsuro Fujii Atsushi Takahara Toshiaki Miyazaki Kazuo Hagimoto Sadayasu Ono 《光学学报》2003,23(Z1)
Super High Definition (SHD) movies were successfully transmitted as streaming contents at about 300 Mbps for the first time over a long distance IP network (more than 3,000 km), in conjunction with the experimental verification of traffic control and scalable multicast technologies. 相似文献