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排序方式: 共有417条查询结果,搜索用时 15 毫秒
41.
Naotsugu Itoh Takuya Machida Wei-Chun Xu Hisamichi Kimura Tsuyoshi Masumoto 《Catalysis Today》1995,25(3-4):241-247
Amorphous PdxSi1-x(x=0.8,0.825,0.85) in the form of ribbon was prepared by a single-roller melt spinning technique to examine hydrogen permeability and catalytic activity for dehydrogenation. As a result, it was found that the amorphous specimens had higher tenacity and higher permeability of hydrogen than its crystallized form. Also, the surface of the amorphous specimen showed a catalytic activity for dehydrogenation of cyclohexane, while no activity was observed in the untreated. Taking advantage of both hydrogen permeability and catalytic activity, the amorphous PdxSi1-x would be expected to be a candidate for a catalytic membrane. 相似文献
42.
C Zhou N Nagayama Y Ohtsuka K Machida M Mori T Katayama 《Canadian Metallurgical Quarterly》1995,33(11):1180-1185
Chest roentgenograms and results of pulmonary-function tests in patients with pulmonary tuberculosis sequelae 30 years after bilateral thoracoplasty were studied retrospectively to detect airway obstruction in these patients and to determine its causes. For periods of more than 10 years, vital capacity (VC) changed at a rate of 15.5 +/- 5.0 ml/year, and forced expiratory volume in one second as a percent of VC (FEV1%) changed at a rate of 0.546% +/- 0.380% per year (n = 13). Thirty years after thoracoplasty, the VC was 920 +/- 180 ml (%VC = 28.4% +/- 5.3%), and the FEV1% was 66.2% +/- 13.7% (n = 21). Thus, mild airway obstruction was found in about half of the cases. For each patient, the distance from the hilum to the diaphragm was measured along the mid-clavicular line on the side with fewer ribs resected, and this distance was divided by the patient's height. The results of that computation was found to be significantly and negatively related to FEV1% (r = -0.681, which suggests that longer bronchi in the lower and middle lobes on that side were associated with lower values of FEV1%. These findings are similar to those in patients with pulmonary tuberculous sequelae after total pneumonectomy. Over an average of 26 years, scoliosis, the vertebra showing the most bending, the intrapulmonary lesion, and the position of the diaphragm did not change, but the cardio-thoracic ratio increased. 相似文献
43.
K. Takatsuji M. Kawakami Y. Makita K. Murakami H. Nakayama Y. Miura N. Shimoyama H. Machida 《Thin solid films》2003,430(1-2):116-119
Si–C films with the Si compositions ranging from 40 to 70% have been grown by Cat-CVD using dimethylsilane [DMSi, Si(CH3)2H2] compounds. Tetraethoxysilane [TEOS, Si(OC2H5)4] and dimethyldimethoxysilane [DMDMOS, Si(CH3)2(OCH3)2] gas source gave us Si–C–O (C-doped SiOx) films with wide ternary alloy compositions. The dielectric constant of a Si–C film has been evaluated by C–V measurements (at 1 MHz) using Al/Si–C/n-Si(001)/Cu MIS structure. The relative dielectric constant value of a Si–C film was estimated to be 3.0. The resistivity of the Si–C layer with 1 mm diameter and 0.24 μm thickness was estimated to be more than 24.5 Gohm·cm. These results gave us promising characteristics of Si–C and Si–C–O films grown by alkylsilane- and alcoxysilane-based Cat-CVD. 相似文献
44.
An optical-transmission error-rate experiment is described in which a graded-index fibre up to 5 km long is used as a transmission medium. It is shown that impairments in the transmission are mainly determined by the total frequency response of the transmission medium, including the fibre and its connection. 相似文献
45.
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
46.
Long-span single-mode fibre transmission experiments at 1.3 ?m have been refined toward higher digit rate and longer fibre span. Error-rate against receiving optical level characteristics showed that optical power penalties at 100 Mbit/s, 1.2 Gbit/s and 1.6 Gbit/s are negligible, even after 30 km, 23 km and 13 km fibre transmission, respectively. 相似文献
47.
Shortest path, shortest spanning tree, complete graph, number of comparisons, expected complexity 相似文献
48.
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
49.
50.
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