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131.
A new model of fatigue crack propagation is proposed which takes the effect of cyclic stress ratio into account. In the model it is assumed that the fatigue crack propagation rate is proportional to the absorbed hysterisis energy per stress cycle at the tip of a crack. The energy is calculated from stress field resulting from the Dugdak-Barenblatt Model and strain field from an experimental result. The model was applied to analyse the experiments on several materials. 相似文献
132.
Yamada J. Machida S. Mukai T. Tsuchiya H. Kimura T. 《Quantum Electronics, IEEE Journal of》1980,16(8):874-884
Experimental and analytical results on high-speed optical pulse transmission characteristics for long-span single-mode fibers by using InGaAsP lasers, emitting at 1.1, 1.3, and 1.5 μm, as well as a Ge-APD are reported. At 1.1 μm, 400 Mbit/s transmission experiments were successfully carried out with 20 km repeater spacing. At 1.3 μm, where single-mode fiber dispersions approach zero, error rate characteristics showed that optical power penalties at 100 Mbits/s and 1.2 Gbits/s are negligible even after 30 and 23 km fiber transmission, respectively. It was confirmed that a 1.6 Gbit/s transmission system has 15 km repeater spacing. At 1.5 μm, where silica fibers have ultimately minimum loss, single-mode fiber transmission experiments were carried out at 100 Mbits/s with about 30 km repeater spacing. 400 Mbit/s transmission characteristics using 20 km fibers were also studied. Fiber bandwidths, measured by optical pulse broadenings after 20 km transmission, were 24, 140, and 37 GHz . km . nm at 1.1, 1.3, and 1.5 μm, respectively. Progress in lasers, fibers, and optical delay equalizers at 1.5μm will bring about large-capacity transmission systems having about 150 km repeater spacing. These results reveal fiber dispersion characteristics in the long wavelength region essential to high data rate single-mode fiber transmission system design. 相似文献
133.
The tunneling conductance is calculated by the use of a theory extending the Kaiser-Zuckermann theory. The superconducting proximity effect in a superconductor-normal metal sandwich system in which the metal on the normal side contains dilute 3d transition metal impurities is taken into account fully. An analysis for experimental results of the tunneling conductance on CuCr backed by Pb is presented. Qualitative agreement between the present calculations and the experimental data is obtained. 相似文献
134.
C. E. Bakis Lawrence C. Bank V. L. Brown E. Cosenza J. F. Davalos J. J. Lesko A. Machida S. H. Rizkalla T. C. Triantafillou 《Canadian Metallurgical Quarterly》2002,6(2):73-87
A concise state-of-the-art survey of fiber-reinforced polymer (also known as fiber-reinforced plastic) composites for construction applications in civil engineering is presented. The paper is organized into separate sections on structural shapes, bridge decks, internal reinforcements, externally bonded reinforcements, and standards and codes. Each section includes a historical review, the current state of the art, and future challenges. 相似文献
135.
Heterojunction switching photodiodes (InGaAs/InP) were used to construct a 3×3 matrix switch. Isolation and cross-talk losses were better than 63 dB over a frequency range of 10 Hz to 400 MHz and 400 Mbit/s digital signals were switched with switching times shorter than 30 ns. 相似文献
136.
Shinjiro Machida Takeshi Wakamatsu Sadahiro Masuo Hiroshi Jinnai Akira Itaya 《Thin solid films》2008,516(9):2615-2619
We prepared nanoparticles of an organic dye, acridine orange (AO), dispersed in poly(methacrylic acid) (PMA) films by spin-coating the solution of the two components. The surface of the AO/PMA films became bumpier with increasing AO concentration (cAO). The absorption and fluorescence spectra of AO/PMA films exhibited a marked dependence on cAO at low cAO (cAO < 2.1 × 10− 1 mol kg− 1), and were independent of cAO at high cAO (cAO > 2.1 × 10− 1 mol kg− 1). The peak shift of fluorescence spectra with changing cAO was as large as ∼ 100 nm. 相似文献
137.
An exploration of nitrate concentrations in groundwater aquifers of central-west region of Bangladesh 总被引:2,自引:0,他引:2
Majumder RK Hasnat MA Hossain S Ikeue K Machida M 《Journal of hazardous materials》2008,159(2-3):536-543
Groundwater and river water samples were collected from the study area to investigate the spatial distribution of nitrate (NO(3)(-)) in the central-west region of Bangladesh. The shallow and deep groundwater nitrate concentrations ranged from <0.10 to 75.12 and <0.10 to 40.78 mg/L, respectively. Major river water NO(3)(-) concentrations were ranged from 0.98 to 2.32 mg/L with an average of 1.8 mg/L. The average Cl(-)/NO(3)(-) ratio (4.9) of major river water has been considered as reference point to delineate denitrification processes. The alluvial fan, alluvial, deltaic and coastal deposits shallow groundwater having C1(-)/NO(3)(-) values less than that of the average river water value (4.9), suggested denitrification processes within the aquifers. On the other hand, denitrification processes are insignificant in the Pleistocene terraces area aquifers related to relatively higher concentrations of nitrate. Iron pyrite has been found as insignificant effect on denitrification. 相似文献
138.
The performance of crystalline photovoltaic (PV) modules has been measured once a year in field exposure. Their maximum power output (Pmax) decreases 4.8% for single-crystalline PV modules and 2.0% for the poly-crystalline case in comparison with their initial Pmax at ex-work after five years' field exposure.This paper describes the secular degradation of crystalline PV modules. 相似文献
139.
Yamada T Fujimoto Y Yamamoto Y Machida K Oda M Fujie M Usami S Nakayama H 《Journal of Bioscience and Bioengineering》2003,95(6):601-607
Three minichromosomes, miniP7, miniB7, and miniK4 of 800 kbp, 450 kbp, and 550 kbp, respectively, were obtained from Chlorella vulgaris chromosome I by electron-beam irradiation. Two of them were structurally characterized: MiniP7 was formed by the deletion of an internal 180 kbp close to the right end of chromosome I. The 180-kbp region with a small interspersed nuclear element (SINE)-like element on its left terminus was translocated to another chromosome, leaving a footprint-like structure on miniP7. MiniB7 was a hybrid of chromosome I and another chromosome, retaining the left telomere and the centromere of chromosome I. The centromeric repetitive elements served as a rearrangement point in the miniB7 formation. These examples showed the complicated mechanisms involved in the minichromosome formation. The minichromosomes thus obtained can be useful for isolating the fundamental structural elements of a chromosome. Moreover, they may serve as starting materials or a vector to generate artificial chromosomes carrying useful genes. 相似文献
140.
H. Nakamura T. Machida M. Iguchi T. Yamasaki A. Kaneko H. Kariya D. Morohoshi S. Ooi T. Mochiku K. Hirata T. Hasegawa H. Sakata 《Journal of Superconductivity and Novel Magnetism》2013,26(8):2633-2635
Using scanning tunneling microscopy and spectroscopy (STM/STS) at 4.2 K, we observed Zn impurity resonance states in single crystals of Zn substituted Bi2Sr2Ca(Cu1?x Zn x )2O8+δ . Zn impurity resonances were characterized by the peak structure in the local density of states (LDOS). The peaks were appeared near the E F on each of Zn impurity sites. The peak energy showed a wide distribution from ?7 to 5 meV. The average peak energy was ?1.5 meV and the variance was 1.8 meV. We investigated the correlation between the peak energy at a Zn site and the energy gap value in the region where the Zn site is embedded. Although we observed about hundred Zn sites, no correlation between the local energy gap and the peak energy was observed. 相似文献