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41.
Yamada Jun-Ichi Machida Susumu Mukai Takaaki Kano Hiroyuki Sugiyama Koichi 《Electronics letters》1979,15(19):596-597
Modulation experimenting on a buried-stripe (b.s.) InGaAsP laser emitting at 1.3 ?m was carried out up to 2 Gbit/s. The b.s. laser is free from relaxation oscillation, which degrades modulated optical pube waveforms, especially at high data rates. The repeater gain of 1.6 Gbit/s transmission systems is improved by 9 dB compared with previously reported experiments. Modulation characteristics up to 2 Gbit/s are reported. 相似文献
42.
Shortest path, shortest spanning tree, complete graph, number of comparisons, expected complexity 相似文献
43.
It has been confirmed by a preliminary transmission experiment that a repeater spacing at 800 Mbits/s can be lengthened up to 7.3 km, by using a combination of a low-loss single-mode fiber and a well designed AlGaAs laser. The laser is modulated by a signal current superimposed on a dc bias current above the threshold. This modulation scheme avoids the spectrum broadening of the laser at the cost of extinction ratio degradation. A discrepancy of about 13 dB exists between the measured and the calculated error-rate performance curves. The major part of the discrepancy, 10 dB, is due to the extinction ratio degradation. 相似文献
44.
45.
Europium(II)-haloborates, Eu2B5O9Cl and Eu2B5O9Br, were synthesized and characterized by X-ray analysis, magnetic susceptibility and luminescent spectral measurements. The chloroborate Eu2B5O9Cl crystallizes in the tetragonal system, D64-P42212, with cell dimensions: a=11.349(4), and Z=4, and Eu2B5O9Br in the orthorhombic system, C102v-Pnn2 or D122h-Pnnm, with cell dimensions: a=11.503(3), b=11.382(3), and Z=4. Both of them were paramagnets with paramagnetic Curie temperature at about ?1 K, and band emissions peaking at about 430 and 435 nm which were based on a 4f7-4f65d transition of Eu2+ ion were observed on Eu2B5O9Cl and Eu2B5O9Br, respectively. 相似文献
46.
47.
Polyacrylic chloride was reacted with aminonaphthol sulfonic acid to give a polymeric intermediate, from which the corresponding dyestuff was prepared by coupling with an aromatic diazonium salt. The water-solubility of the polymeric azo dye was found to depend mainly on the number of sulfonic groups in the molecular chain, and the colouring of dye was comparatively rich in variety. A copolymer of acrylic chloride with methyl methacrylate was directly reacted with a dyestuff containing amino groups to give a polymeric dye. In the molecular chain of those polymeric dyes, the functional structure of the dyestuff was kept by its incorporation to the acrylic polymer chain. 相似文献
48.
Kazushige Machida 《Journal of Low Temperature Physics》1983,53(3-4):405-417
Superconductors containing a magnetically polarizable medium under an applied magnetic field are discussed theoretically. It is shown that instead of the Pauli limiting field found by Chandrasekhar and Clogston for nonmagnetic superconductors, the maximum critical field is limited by the effect of the susceptibility Xf due to the polarizable medium and is greatly reduced as Xf increases, indicating the appearance of the first-order phase transition from the superconducting to the normal state. The magnetic behavior of the ferromagnet superconductor ErRh4B4 under applied fields is analyzed in terms of this idea. 相似文献
49.
Alonso MP Figueiredo AC Borges FO Elizondo JI Galvão RM Severo JH Usuriaga OC Berni LA Machida M 《The Review of scientific instruments》2010,81(10):10D529
We present the first simultaneous measurements of the Thomson scattering and electron cyclotron emission radiometer diagnostics performed at TCABR tokamak with Alfve?n wave heating. The Thomson scattering diagnostic is an upgraded version of the one previously installed at the ISTTOK tokamak, while the electron cyclotron emission radiometer employs a heterodyne sweeping radiometer. For purely Ohmic discharges, the electron temperature measurements from both diagnostics are in good agreement. Additional Alfve?n wave heating does not affect the capability of the Thomson scattering diagnostic to measure the instantaneous electron temperature, whereas measurements from the electron cyclotron emission radiometer become underestimates of the actual temperature values. 相似文献
50.
We succeeded in integrating individual, pre-existing nanostructures into functional devices using ultrahigh vacuum dynamic nanostenciling and show working devices based on single-walled carbon nanotubes, a benchmark nanomaterial, and porphyrin J-aggregates, a "soft" supramolecular nanomaterial. Nanostructures are first located via atomic force microscopy, while device elements are added step by step, with an achieved positional accuracy of 20 nm, using a shadow mask assembly that moves while being exposed to evaporated material. Electronic transport, potentiometry, and scanning Kelvin probe were used for control at any fabrication stage and were available in situ. Such complex fabrication/characterization capabilities, applicable repeatedly, reliably, and nondestructively, pave the way for dynamic nanostenciling instrumentation to establish itself as a viable tool for easy integration and prototyping of fragile nanostructures synthesized through a wide range of processes. 相似文献