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101.
A low-loss polarisation-maintaining optical fibre with low crosstalk is presented. The minimum transmission loss is 0.35 dB/km at 1.54 ?m and crosstalk is ?32 dB at 1.56 ?m in a 1 km length. The relative refractive index difference between core and cladding is 0.3%, and the modal birefringence is 2.8 × 10?4. 相似文献
102.
Toshiro Kumon Tatsuya Suzuki Makato Iwasaki Motoaki Matsuzaki Nobuyuki Matsui Shigeru Okuma 《Electrical Engineering in Japan》2003,142(4):45-55
The requirement for the high‐quality control of complex and/or structure‐unknown plant is growing in the real‐world industrial machine. Indirect Adaptive Control (IAC), which identifies model and updates the controllers automatically, is one promising way expected to meet this requirement. The conventional IAC, however, is required to know the structure of the controlled plant, that is, the order of its transfer function, in advance. This paper presents a new IAC scheme which makes use of Genetic Algorithm (GA) in its identification part. In the proposed framework, the information on the order of the plant is not required since the genetic algorithm searches both the structure of the plant dynamics and its parameters autonomously. A two‐degree‐of‐freedom Internal Mode Control (IMC) is adopted as a basic control architecture since the indirect adaptation can be harmoniously embedded in it. The effectiveness of the proposed scheme is verified through numerical simulations and experiments applied to a velocity control of multimass systems. © 2003 Wiley Periodicals, Inc. Electr Eng Jpn, 142(4): 45–55, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10103 相似文献
103.
K Inukai M Funaki T Ogihara H Katagiri A Kanda M Anai Y Fukushima T Hosaka M Suzuki BC Shin K Takata Y Yazaki M Kikuchi Y Oka T Asano 《Canadian Metallurgical Quarterly》1997,272(12):7873-7882
Phosphatidylinositol 3-kinase (PI 3-kinase) is stimulated by association with a variety of tyrosine kinase receptors and intracellular tyrosine-phosphorylated substrates. We isolated a cDNA that encodes a 50-kDa regulatory subunit of PI 3-kinase with an expression cloning method using 32P-labeled insulin receptor substrate-1 (IRS-1). This 50-kDa protein contains two SH2 domains and an inter-SH2 domain of p85alpha, but the SH3 and bcr homology domains of p85alpha were replaced by a unique 6-amino acid sequence. Thus, this protein appears to be generated by alternative splicing of the p85alpha gene product. We suggest that this protein be called p50alpha. Northern blotting using a specific DNA probe corresponding to p50alpha revealed 6.0- and 2.8-kb bands in hepatic, brain, and renal tissues. The expression of p50alpha protein and its associated PI 3-kinase were detected in lysates prepared from the liver, brain, and muscle using a specific antibody against p50alpha. Taken together, these observations indicate that the p85alpha gene actually generates three protein products of 85, 55, and 50 kDa. The distributions of the three proteins (p85alpha, p55alpha, and p50alpha), in various rat tissues and also in various brain compartments, were found to be different. Interestingly, p50alpha forms a heterodimer with p110 that can as well as cannot be labeled with wortmannin, whereas p85alpha and p55alpha associate only with p110 that can be wortmannin-labeled. Furthermore, p50alpha exhibits a markedly higher capacity for activation of associated PI 3-kinase via insulin stimulation and has a higher affinity for tyrosine-phosphorylated IRS-1 than the other isoforms. Considering the high level of p50alpha expression in the liver and its marked responsiveness to insulin, p50alpha appears to play an important role in the activation of hepatic PI 3-kinase. Each of the three alpha isoforms has a different function and may have specific roles in various tissues. 相似文献
104.
In order to develop an animal model for in vivo testing of the displacing action of various drugs and for study of the bilirubin deposition in the brain, some molecular properties of the serum albumin from different species i.e. pig, cat, human, dog, sheep, guinea pig and rat were investigated. These albumins were found to have differences in molecular weight, Stokes radius and electrophoretic mobility. They also showed different bilirubin binding characteristics when studied by spectroscopy and fluorescence quenching. It is therefore, necessary to consider the species differences when results of animal experimentation are used as a basis for the investigation of human kernicterus. 相似文献
105.
The letter investigates the dispersion of GeO2 glass core and F-doped GeO2 glass cladding single-mode optical fibre. It is estimated that the total dispersion goes to zero at about ? = 1.77 ?m. The material dispersions of these glasses are also measured. Material dispersion of GeO2 glass, which contains fluorine of 0.41 wt%, vanished at ? = 1.722?m. This occurs at ? = 1.734 ?m for pure GeO2 glass. 相似文献
106.
Electrochemically prepared poly(3-methylthienylene) films doped with iodine have been investigated and the relationship between their conductivity and iodine content was studied. The conductivity of the films with various iodine contents was obtained in accordance with an Arrhenius equation with an activation energy equal to 0.17 to 0.033 eV. The highest conductivity was 5 S cm?1. The activation energy, which is dependent on the iodine content, shows discontinuous change, as is the case with polyacetylene doped with iodine. The relationship between conductivity and structure of the poly(3-methylthienylene) films will be discussed. 相似文献
107.
Takeyuki Suzuki Tsutomu Yamazaki Eiji Hosaka Hiroshi Yoshioka 《Journal of Materials Science》1985,20(11):4155-4162
A single-roller apparatus was used to quench 16 melts in the Bi2O3-WO3 system. Metastable polycrystalline phases were obtained in all compositions. Quenched specimens and their phase transformations on heating were examined by X-ray diffraction, differential thermal analysis, density measurement, electrical measurement and observation of optical anisotropy. F c c solid solutions of the type, 2WO3 2W
Bi
+ 30
pI
+30
X
PO
occurred in the quenched samples for 18 to 32 mol % WO3. Quenched phases remained unchanged with only a slight structural relaxation at temperatures lower than the first exotherm. Near the first exotherm, most samples showed an irregular change in the lattice parameter(s). 相似文献
108.
109.
Microfluidic chip toward cellular ATP and ATP-conjugated metabolic analysis with bioluminescence detection 总被引:3,自引:0,他引:3
Liu BF Ozaki M Hisamoto H Luo Q Utsumi Y Hattori T Terabe S 《Analytical chemistry》2005,77(2):573-578
In this article, a microfluidic platform integrating capillary electrophoresis and bioluminescence (BL) detection that was fabricated in poly(dimethylsiloxane) (PDMS) with lab-on-a-chip technology was demonstrated for cellular metabolic analyses. A microchannels network, "cross combining with Y", was designed to perform on-chip sample preparation, separation, and BL detection of ATP and ATP-conjugated metabolites, using firefly luciferin-luciferase BL system. A dynamic modification of the channel wall of PDMS proved to be crucial to reverse the direction of electroosmotic flow (EOF), which was uniquely achieved by a prewash cycle with a cationic surfactant didodecyldimethylammonium bromide. The influences of surfactant on the EOF and BL reaction were also investigated. Quantitative analyses revealed a dynamic linear range over 2 orders of magnitude for ATP, with a detection limit down to submicromolar (midattomole). The method was validated by measuring cellular ATP of E. coli. with direct on-chip cell lysis. Further work was emphasized on ATP-conjugated metabolite analysis, using galactose as an example. Assays of galactose in human urine samples confirmed the reliability of the protocol, which revealed good prospect of this platform for ATP-conjugated submetabolomic profiling. 相似文献
110.
Thermosensitive dielectric properteis in polyamide–phenol hybrid compounds have been studied. The polyamide–phenol hybrid compounds are constituted of p-hydroxybenzoate–formaldehyde condensation oligomer dispersed molecularly in nylon 12 and polyamide copolymer. These materials are less hygroscopic than nylon 12 which is the least hygroscopic among polyamide homopolymers. It will be because the phenol group coordinates to amide group as the less hygroscopic “pseudo-water” instead of water. One of these materials has also shown an intrinsic hydrophobic effect of hydrogen bond segment due to the “hybrid effect” between polyamide and phenol. The thermosensitive dielectric properties are based on the temperature dependence of intermolecular hydrogen bond behaviors by amide and phenol groups, which have been discussed in relation with the molecular behaviors. The relationship with polarizations constituting dielectric constant and hydrogen bonding molecular segments, and ac hopping conduction behaviors by proton carriers have also been discussed. These materials are applied as a temperature-sensing material in a flexible thermosensing heater wire, which has three functions, that is, thermosensing, heating, and fusing for safe in the case of an abnormal overheat. As the features for a sensing material, these materials show the humidity low-dependence and highly thermal stability, and will be situated as one of the high-performance sensing material useful for the electric warmer such as an electric blanket. 相似文献