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71.
Yoshimura T. Inoguchi T. Yamamoto T. Moriya S. Teramoto Y. Arai Y. Namiki T. Asama K. 《Lightwave Technology, Journal of》2004,22(9):2091-2100
This paper presents core technologies for a self-organized microoptical system (SELMOS) within optoelectronic computers; mass-productive fabrication processes of waveguide films and new types of self-organized lightwave networks (SOLNETs) for three-dimensional (3-D) optical wiring with optical Z-connections. Waveguide films are fabricated by the built-in mask method, which is reusable and can construct surface-normal mirrors/filters at one time within photolithographic accuracy. Beveled core edge walls are made by the tilted ultraviolet (UV) exposure through the built-in mask using a photodefinable material. Near- and far-field patterns reveal that the walls act as micromirrors for optical Z-connections. SOLNET is a network consisting of self-organized coupling waveguides between misaligned optical devices. The self-organization is generated in a photorefractive material by self-focusing of the two write beams from the two devices. Direct SOLNET, where wavelengths of the write beam and the signal beam are the same, is demonstrated using a laser diode. Reflective SOLNET, where one of the two write beams is replaced with a reflected write beam from the edge of the coupled device, realizes two-beam-writing SOLNET in a one-beam-writing configuration. It is especially effective when the coupled device cannot transmit write beams. The proof-of-concept is demonstrated both theoretically and experimentally. These results indicate a possibility to form 3-D optical wiring simply in SELMOS. 相似文献
72.
73.
It has been confirmed, from observations with an electron microscope after staining negatively with aqueous uranyl acetate
solutions and using a flourescent microscope, that sucrose fatty acid esters form closed vesicles. The range of particle size
of the vesicle, consisting of chromatographically fractionated sucrose dilaurate, was apparently 70–700 nm in the longer diameter
of individual vesicles based on the transmission electron microscopic (TEM) observation. The weight-average particle size
was 424 nm as shown by means of the photon-correlation method. The amounts of 6-carboxyfluorescein trapped in the vesicles
of sucrose fatty acid esters were determined, and it was ascertained that the volumes of the central water phase depended
upon the acyl chain lengths of fatty acid residues. Further, the effect of the additives [cholesterol and dicetyl phosphate
(DCP) was examined. As an example, the vesicle of sucrose stearate had a central water phase of 1.7 one water/mol ester, and
showed a slow release of 6-carboxyfluorescein from the central water phase after preparation of the vesicle. 相似文献
74.
Amorphous carbon materials for lithium ion battery anodes which contain a small amount of Li2CO3 were prepared by three methods. The obtained materials were characterized using X-ray diffraction (XRD) analysis, Raman spectroscopy and CO2 adsorption experiments. Although the XRD profiles and Raman spectra of these materials were similar to those of carbon materials synthesized with no addition, the amount of CO2 adsorbed was largely decreased by Li2CO3 addition. These results suggest that the micropores in these materials were plugged and/or filled with Li2 CO3. Galvanostatic lithium charging and discharging experiments showed that the irreversible capacity of the material can be significantly decreased by Li2CO3 addition, which is thought to be due to the plugging of the pore inlets by Li2CO3. Moreover, it was also found that the reversible capacities of the materials can be increased by adjusting both the amount of Li2CO3 addition and carbonization temperature. 相似文献
75.
This article deals with preparations of fine particles of metallocene copolymers by emulsifierfree emulsion polymerization of vinylferrocene (VFc), ferrocenylmethyl methacrylate (FMMA), 1-ferrocenylethyl methacrylate (1-FEMA), 2-ferrocenylethyl methacrylate (2-FEMA), and 1-ruthenocenylethyl methacrylate (1-REMA) with acrylonitrile (AN), styrene (St), and methyl methacrylate (MMA) in water/ethanol medium. As a result, spherical copolymer particles containing metallocene derivatives have been successfully synthesized in the particle size of ca. 120 to 600 nm. The contents of ferrocenyl or ruthenocenyl groups in copolymer particles increased with increasing concentration of charged metallocene derivatives, while the amounts of metallocene derivatives incorporated into particles are much lower than the charged ratio. © 1994 John Wiley & Sons, Inc. 相似文献
76.
Food processing environments are suspected to be the primary source of Listeria monocytogenes contamination of foods. We investigated the survival of L. monocytogenes on stainless steel that was soiled with food components (minced tuna, ground pork, and cabbage) followed by dehydration. Stainless steel coupons were inoculated with 107 CFU/coupon and stored up to 30 days. In comparison with Staphylococcus aureus and Salmonella Typhimurium, L. monocytogenes demonstrated the highest survivability where about 3 log CFU/coupon remained at the end of the experimental period. While survival during the early storage period was markedly affected by both food-component attachment and food type, a long dehydration period diminished the effect of those. 相似文献
77.
Aiba Shinya Ota Terukazu Tsuchida Hajime 《International Journal of Heat and Mass Transfer》1980,23(3):311-319
An experimental investigation of heat transfer around four cylinders closely spaced in a cross-flow of air has been conducted. The cylinders are settled in tandem with equal distances between centers. Their inline pitch ratio is in the range of (c = distance between cylinders' centers, d = cylinder diameter); the Reynolds number ranges from 104 to 5 × 104. It is found that there exists a critical Reynolds number Redc at which the heat transfer behavior changes drastically, and is correlated with the in-line pitch ratio by .Variations of characteristic features of the mean and local Nusselt numbers are discussed in relation to the length of the vortex formation region behind the cylinder. 相似文献
78.
Shiho Kuwashiro Yoshiro Hatanaka Kousaku Tao Seiji Higashi Keitaro Kago Hiroshi Hirano Hajime Kishi 《应用聚合物科学杂志》2024,141(19):e55315
Amorphous polymer/crystalline polymer blends can be prepared via the simultaneous polymerization of polymethacrylate/polyurethane combinations. The relationship between higher order structures and fracture mechanisms in these blends must be uncovered to elucidate the source of the increased fracture toughness of such materials. The present work involves the production of blended polymethacrylate/polyurethane and assess the internal structures of these specimens using optical and electron microscopy. These observations reveal the presence of both spherulites and elastomeric phases. The spherulites consisting of the polyurethane and are several micrometers in diameter whereas the phase-separated polyurethane elastomeric domains are approximately 100 nm in size. Multiple cracks, crack bridging and plastic deformation around the precrack tips of loaded specimens are evidently responsible for the increased toughness of these blends. The former two phenomena are attributed to the presence of spherulites while the plastic deformation of the methacrylate matrix is ascribed to cavitation of the polyurethane elastomeric phases in response to loading. 相似文献
79.
Runwei Cheng Tatsumi TosawaMitsuo Gent Hajime Kato Yoshimasa Takayama 《Computers & Industrial Engineering》1996,31(3-4):867-871
This paper reports our experiment on training a three layer forwards neural network with backpropagation algorithm (BP) to memorise acoustic emission (AE) behaviors of magnesium alloy during fatigue test process and perform the mapping from AE behaviors to fatigue crack propagation. This study reveals the potential possibility of using artificial neural networks for automated AE testing. Simulation results are very encouraging and conclusively in favor of this attempt. 相似文献
80.
The maximum liquid phase penetration and evaporation behavior was investigated by using simultaneous measurement for mie-scattered light images and shadowgraph ones. The objective of this study was to analyze effect of variant parameters and fuel properties on evaporation behavior, and to investigate liquid phase penetration for the single- and multi-component fuels. The experiments were conducted in a constant-volume vessel with optical access. Fuel was injected into the vessel with electronically controlled common rail injector. It was observed that: liquid phase length is influenced by fuel properties. High-boiling point fuel within the multi-component fuel controls liquid phase length. 相似文献