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31.
Photonic bandgap fibers with high birefringence 总被引:6,自引:0,他引:6
A highly birefringent air-guiding photonic crystal fiber which provides guidance by a full two-dimensional photonic bandgap (PBG) effect is proposed. The fiber core is formed by introducing a large air hole that has an area of four unit cells of the cladding materials. It is shown from computed results by a full-vector finite element method that the proposed PBG fiber has birefringence of the order of 10/sup -3/. 相似文献
32.
The oil film thickness was measured under conditions of minute vibrations using an elastohydrodynamic lubrication (EHL) ball-on-disk test rig. Poly-alpha-olefin (PAO) oil was used as the lubricant under conditions of pure sliding where only the ball specimen was minutely vibrated. It was found that an oil film formed when the amplitude ratio was greater than 1.6. Moreover, when conditions were changed to the maximum vibrating speed, oil viscosity, and maximum contact pressure, the critical amplitude ratio at which the oil film began to form remained at 1.6. Consequently, calculated results showed that the oil film was formed when the amplitude ratio was π/2 (nearly equal to 1.6), which closely agreed with our test results. 相似文献
33.
Shoichiro Yamamoto Tadahide Kurokawa Masashi Sekino Motoshige Yasuike Kenji Saitoh 《International journal of molecular sciences》2013,14(11):23153-23159
We developed tetranucleotide-repeat microsatellite markers for the masu salmon (Oncorhynchus masou) complex. 454 pyrosequencing was used to discover repeat motifs, and seven polymorphic microsatellite-primer sets were identified. The number of alleles detected at each locus ranged from four to 24 and the expected heterozygosity varied from 0.57 to 0.92. Cross-subspecies amplification for O. m. masou, O. m. ishikawae and O. m. subsp. was successful. These microsatellites can be utilized in studies of genetic structure, genetic diversity, and intra- and inter-subspecific hybridization, making a contribution to conservation and management of the Oncorhynchus masou complex. 相似文献
34.
Keisuke TanizawaTetsuo Sekiya Shigeo OhshioHiroki Akasaka Hidetoshi Saitoh 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(3):313-317
The development of an intense X-ray source using backscattered X-ray produced using an advanced electrode configuration is described. The electrodes were composed of field emitters deposited on a wire mounted on a perforated plate as the cathode and a copper plate as the anode. Electrons from these emitters collided with the copper plate and X-ray was generated at collision points. The backscattered X-ray in the direction normal to the electron trajectory through a hole in the anode escaped from the vacuum chamber through a beryllium window. Continuous and characteristic X-rays were detected at an applied voltage lower than that of a conventional X-ray source from 3.0 to 9.4 kV, respectively. Moreover, the X-ray dosage measured with a survey meter reached 0.95 mSv/h at 5.0 kV of applied voltage. The transmission images of three types of material used as an X-ray source for the X-ray imaging system indicate three advantages; low power consumption, focal point controllable by adjusting applied voltage, and photographable motion picture of X-ray transmission. 相似文献
35.
36.
Saitoh M Asaka K Arai M Kawabata A Kanoh S Kanoh T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(4):243-249
In order to evaluate the relationship between nasal carriers of S. aureus and their history of allergic diseases, the total serum IgE titer, the hemogramme pattern, and the titers of specific IgE antibody to Staphylococcal enterotoxins A and B (SEA and SEB) and of specific IgG antibody to SEB were investigated in 98 trade school students. Fifteen (15.3%) of the 98 students were sensitized to SEA and/or SEB (40.0% to SEA and 93.3% to SEB). In this group, 11 subjects were S. aureus carriers (73.0%) and 12 had a history of allergic diseases (80.0%). Low levels of specific IgG antibody to SEB were identified from both S. aureus carriers and non-carriers. The S. aureus carriers had significantly higher levels of total IgE titer than the non-carriers and the individuals with a history of allergic diseases had significantly higher total IgE titer levels than those having no history of allergic diseases (p < 0.01). In the hemogramme patterns of S. aureus carriers, a significant positive correlation was observed between the total IgE antibodies and the eosinophil rate (p < 0.05), and a negative correlation (p < 0.001) was recognized between the neutrophil and the lymphocyte rates. 相似文献
37.
Electrochemical removal of p-nonylphenol from dilute solutions using a carbon fiber anode 总被引:4,自引:0,他引:4
p-Nonylphenol, which is widely used as raw material in industrial activities has been regarded as an environmental endocrine disrupter. In an effort to develop a new treatment method for p-nonylphenol, we initially investigated the electrochemical behavior of p-nonylphenol by voltammetric techniques. The electrochemical oxidation of p-nonylphenol led to the formation of electropolymerized film on the glassy carbon electrode surface. The fouling on the electrode surface by the electropolymerized film was evaluated by monitoring the electrode response of ferrocyanide ions as the redox marker. The electrochemical removal of p-nonylphenol based on the formation of the electropolymerized film on an anode surface was performed using a carbon fiber (CF) with a very large surface area. The high removal efficiency for p-nonylphenol was obtained by applying a potential at 0.7 V. The maximum surface coverage of electropolymerized p-nonylphenol on the CF was about 5 x 10(-9) mol/cm2. The presence of humic acid hardly inhibited the removal of p-nonylphenol. Furthermore, the application to the removal of phenol, o-chlorophenol, p-chlorophenol, 2,4-dichlorophenol, and 2,4,5-trichlorophenol was attempted by using this method. 相似文献
38.
Kondoh Y. Takenaka T. Hidaka T. Tejima G. Kaneko Y. Saitoh M. 《Journal of microelectromechanical systems》2005,14(2):214-220
Existing mechanical relays have reliability-related issues including unstable contact resistance and limited cycle life. These problems are caused by mechanical fatigue and wearing of the contact surfaces. In the liquid metal micro switch (LiMMS), we employ a liquid-liquid contact to address these issues. The switching operation is achieved by forming a gap in the liquid metal using gas expansion. Our prototype has a microchannel on a glass substrate to hold a tiny amount of mercury, 0.15 mm in width and 0.1 mm in height, and TaN thin-film heaters on a ceramic substrate to expand the operating gas by heating. The substrates are bonded together and the total size of the device is 5/spl times/5/spl times/1.4 mm. We successfully demonstrated 70-m/spl Omega/ on-resistance, 1 ms-switching speed, the ability to handle up to 1 A of dc current and over 1/spl times/10/sup 8/ cycle operation. LiMMS also has good RF performance, better than 1 dB insertion loss, and better than 20 dB isolation up to 18 GHz. 相似文献
39.
40.
Morphological changes of liposomes caused by interactions between liposomal membranes and talin, a cytoskeletal submembranous protein, were studied by direct, real-time observation by using high-intensity dark-field microscopy. Surprisingly, when talin was added to a liposome solution, liposomes opened stable holes and were transformed into cup-shaped liposomes. The holes became larger with increasing talin concentration, and finally the cup-shaped liposomes were transformed into lipid bilayer sheets. These morphological changes were reversed by protein dilution, i.e., the sheets could be transformed back into closed spherical liposomes. We demonstrated that talin was localized mainly along the membrane verges, presumably avoiding exposure of its hydrophobic portion at the edge of the lipid bilayer. This is the first demonstration that a lipid bilayer can stably maintain a free verge in aqueous solution. This finding refutes the established dogma that all lipid bilayer membranes inevitably form closed vesicles and suggests that talin is a useful tool for manipulating liposomes. 相似文献