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2.
A narrow linewidth has been obtained in a new 1.5 ?m distributed feedback laser integrated monolithically with a tunable external cavity. The linewidth of 18 MHz has been achieved by tuning the current in the external cavity, and the FM response was flat from 100 kHz to 500 MHz. 相似文献
3.
External Synchronization of 160-GHz Optical Beat Signal by Optical Phase-Locked Loop Technique 总被引:1,自引:0,他引:1
We have synchronized a 160-GHz optical beat signal with a 40-GHz reference optical pulse train by using an optical phase-locked loop (OPLL). The OPLL consists of an optical beat signal source, comprising a pair of three-electrode distributed feedback laser diodes that works as a voltage controlled oscillator, and an all-optical phase detector based on the two-photon absorption in a silicon avalanche photodiode. Phase-locking operation is confirmed through phase-error measurement and cross-correlation trace measurement. The residual timing jitter of the 160-GHz optical beat signal relative to the reference pulse train, in the bandwidth of 80 MHz, is measured to be as small as 126 fs 相似文献
4.
The effects of carbon-fiber chips and carbon brushes as additives on the thermal conductivity enhancement of phase change materials (PCMs) using in latent heat thermal energy storage are investigated experimentally and numerically by considering the wall effect of the additives. The carbon-fiber chips are effective for improving the heat transfer rate in PCMs. However, the thermal resistance near the heat transfer surface is higher than that for the carbon brushes. As a result, the overall heat transfer rate for the fiber chips is lower than that for the carbon brushes. Consequently, the carbon brushes are superior to the fiber chips for the thermal conductivity enhancement under the present experimental conditions. The carbon brushes are moreover applied to the packed beds of particles to overcome their low thermal conductivity in chemical heat pump/storage. The carbon brushes essentially improve the heat transfer characteristics in the packed beds, though the thermal resistance is observed because the particles obstruct contact between the fibers and the heat transfer surfaces. 相似文献
5.
Yukio Sato Tomohito Tanaka Fumiyasu Oba Takahisa Yamamoto Yuichi Ikuhara Taketo Sakuma 《Science and Technology of Advanced Materials》2003,4(6):137
SrTiO3 and ZnO bicrystals with various types of boundaries were fabricated in order to examine their current–voltage characteristics across single grain boundaries. Their grain boundary structures were also investigated by high-resolution transmission electron microscopy. In Nb-doped SrTiO3, electron transport behaviors depend on the type of boundaries. Random type boundaries exhibit highly non-linear current–voltage characteristics, while low angle boundaries show a slight non-linearity. On the contrary, undoped ZnO does not exhibit non-linear current–voltage characteristics in any type of boundaries including random ones. It is suggested that the differences observed in current–voltage properties between the two systems are mainly due to the difference in the accumulation behavior of acceptor-like native defects at grain boundaries. A clear non-linearity is obtained by means of Co-doping even for the highly coherent Σ1 boundary in a ZnO bicrystal. This is considered to result from the production of acceptor-like native defects by Co-doping. 相似文献
6.
Silkworms and spiders have evolved complex spinning apparatus thought to use highly controlled conditions to optimize protein folding and crystallization to provide a tough fiber. Accordingly, the structure and function of the natural spinning apparatus has been studied with great attention as an interesting piece of biological engineering with potential for mimicry in an industrial process. However it is still not well understood. Here we used Micro-Computerized Tomographic equipment (mCT) to visualize the three-dimensional structure of the spinning apparatus in Bombyx mori silkworms. Multidirectional tomograms obtained by X-ray radioscopy provided valuable information on the detailed arrangement of each muscle of the silk press. It is suggested that the duct in the silk press part plays a part as an extrusion die whose cross-sectional area can be controlled by muscles to optimize applied stresses in the partially gelled silk within its lumen. 相似文献
7.
Haruo Mimura Ryusei Sato Yu Sasaki Yuichi Furuyama Akira Taniike Kazutoshi Yoshida Akira Kitamura 《International journal of molecular sciences》2008,9(10):1989-2002
Tributyltin (TBT) released into seawater from ship hulls is a stable marine pollutant and obviously remains in marine environments. We isolated a TBT resistant marine Pseudoalteromonas sp. TBT1 from sediment of a ship’s ballast water. The isolate (109.3 ± 0.2 colony-forming units mL−1) adsorbed TBT in proportion to the concentrations of TBTCl externally added up to 3 mM, where the number of TBT adsorbed by a single cell was estimated to be 108.2. The value was reduced to about one-fifth when the lysozyme-treated cells were used. The surface of ethanol treated cells became rough, but the capacity of TBT adsorption was the same as that for native cells. These results indicate that the function of the cell surface, rather than that structure, plays an important role to the adsorption of TBT. The adsorption state of TBT seems to be multi-layer when the number of more than 106.8 TBT molecules is adsorbed by a single cell. 相似文献
8.
Shintaro Nakano Nobuyoshi Saito Kentaro Miura Tatsunori Sakano Tomomasa Ueda Keiji Sugi Hajime Yamaguchi Isao Amemiya Masato Hiramatsu Arichika Ishida 《Journal of the Society for Information Display》2012,20(9):493-498
We have successfully reduced threshold voltage shifts of amorphous In–Ga–Zn–O thin‐film transistors (a‐IGZO TFTs) on transparent polyimide films against bias‐temperature stress below 100 mV, which is equivalent to those on glass substrates. This high reliability was achieved by dense IGZO thin films and annealing temperature below 300 °C. We have reduced bulk defects of IGZO thin films and interface defects between gate insulator and IGZO thin film by optimizing deposition conditions of IGZO thin films and annealing conditions. Furthermore, a 3.0‐in. flexible active‐matrix organic light‐emitting diode was demonstrated with the highly reliable a‐IGZO TFT backplane on polyimide film. The polyimide film coating process is compatible with mass‐production lines. We believe that flexible organic light‐emitting diode displays can be mass produced using a‐IGZO TFT backplane on polyimide films. 相似文献
9.
The polymerization of methyl methacrylate by tri-n-butylborane in the presence of amino acid esters was investigated. The binary systems of tri-n-butylborane and amino esters were found to be more effective for initiating the polymerization than tri-n-butylborane alone. Co-catalytic effects of amino acid esters were in the order: tyrosinate > glutamate > aspartate ? phenyl alaninate > serinate > glycinate. The rate of polymerization in a mixture of dimethylsulphoxide and toluene was proportional to the square root of the concentration of the initiator system, to the monomer concentration, and to the concentration of dimethylsulphoxide in the solvent. The overall energy of activation was estimated to be 4.6 kcal/mol for the tri-n-butylborane/methyl tyrosinate system. Copolymerization curves gave a typical free-radical character. 相似文献
10.
Riho Kataishi Takayuki Ikeda Toshiki Sasaki Kouhei Toyotaka Daiki Nakamura Hiroyuki Miyake Yuji Iwaki Kazunori Watanabe Yuichi Yanagisawa Hisao Ikeda Harue Nakashima Nobuharu Ohsawa Shingo Eguchi Satoshi Seo Yoshiharu Hirakata Shunpei Yamazaki Daisuke Kurosaki Masakatsu Ohno Chris Bower Darryl Cotton Andrew Matthews Piers Andrew Catalin Gheorghiu Johan Bergquist 《Journal of the Society for Information Display》2014,22(8):381-392
In this study, white organic electroluminescent devices with microcavity structures were developed. A flexible high‐resolution active‐matrix organic light‐emitting diode display with low power consumption using red, green, blue, and white sub‐pixels formed by a color‐filter method was fabricated. In addition, a side‐roll touch display was developed in combination with a capacitive flexible touch screen. 相似文献