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101.
Shozo Ishizaka John G. Stockner Katsumi Kobayashi Kunihiro Shima Kenji Katori Humitake Seki 《Water research》1983,17(12):1815-1821
Multi-elemental traces comprising particulate matter in natural water collected during summer in 1978 and 1979 from British Columbia, Canada, were analyzed by α-particle excited X-ray fluorometry. Common elements from all waters examined were Si, Cl, Ca and Fe. The similarity of their distribution in different aquatic environments was statistically analyzed. They were distributed homogeneously in the marine environment but heterogeneously in the freshwater environments. No heavy metals concerned with the environmental standards were detected for all waters examined. 相似文献
102.
103.
An experimental guided millimeter-wave transmission system is constructed employing two 806-Mbit/s digital repeaters, an 8.4-km waveguide line loop, and channel coupling networks. This paper presents its characteristics, such as waveforms, amplitude and delay, error rate, and timing jitter in some detail. 相似文献
104.
Sugimoto Shigetoki Minemura Kouichi Kobayashi Kohroh Seki Masafumi Shikada Minoru Ueki Atsufumi Yanase Tomoo Miki Tetsuya 《Electronics letters》1977,13(22):680-682
The letter reports results obtained with laboratory transmission experiments on high-speed digital signals by optical wavelength-division multiplexing, using a newly developed optical multiplexer and demultiplexer, as well as other high-performance optical devices and fibres. 相似文献
105.
If a loss of vacuum event (LOVE) occurs due to damage of the vacuum vessel of a nuclear fusion experimental reactor, some chemical reactions such as a graphic oxidation and a buoyancy-driven exchange flow take place after equalization of the gas pressure between the inside and outside of the vacuum vessel. The graphite oxidation would generate inflammable carbon monoxide and release tritium retained in the graphite. The exchange flow through the breaches may transport the carbon monoxide and tritium out of the vacuum vessel. To add confidence to the safety evaluations and analyses, it is important to grasp the basic phenomena such as the exchange flow and the graphite oxidation. Experiments of the exchange flow and the graphite oxidation were carried out to obtain the exchange flow rate and the rate constant for the carbon monoxide combustion, respectively. These experimental results were compared with existing correlations. We plan a scaled-model test and a full-scale model test for the LOVE. 相似文献
106.
K Hashimoto H Uchimura Y Seki M Watanabe T Yasuda K Ohsawa 《Canadian Metallurgical Quarterly》1993,113(8):600-603
A simple method using ion-pair high-performance liquid chromatography was established for the rapid and precise determination of synephrine in thirty three species of oriental pharmaceutical decoctions containing Aurantii Nobilis Pericarpium. An ODS column and a mixed solvent system of water, acetonitrile, sodium dodecyl sulfate and phosphoric acid as a mobile phase were used for the separation. Synephrine was eluted without interference of other coexisting components within 15 min. 相似文献
107.
E Imaizumi K Seki Y Kikuchi I Nagata S Matsukuma S Aida S Tamai 《Canadian Metallurgical Quarterly》1993,252(4):209-213
A 44-year-old woman with stage IV non-Hodgkin's lymphoma (NHL) of the left ovary is described. She had an extended hysterectomy and bilateral salpingo-ophorectomy and thereafter received six courses of combination chemotherapy (cyclophosphamide, adriamycin, vincristine and predonisolone; CHOP). The patient is well with no evidence of recurrence at 12 months after surgery. The literature on primary ovarian lymphoma is reviewed. 相似文献
108.
Yasushi Seki Isamu Yamauchi Koubun Yamada Hiromitsu Kawasaki 《Journal of Fusion Energy》1983,3(4):241-251
Radioactivation of five types of candidate steel alloys for the structural materials of superconducting toroidal field coils (TFC) of a D-T fusion reactor has been comparatively studied. As a result, the use of a high Mn steel in place of 316 SS is shown to reduce the dose rate at the He vessel of the TFC to ~ 1/3 the value with 316 SS at 1 day after shutdown, and to ~ 1/1000 at 10 years after shutdown. These reductions are mostly caused by the 0.28 wt% Co assumed to be included in 316 SS but none in the high Mn steel. Newly defined dose rate sensitivities of constituent elements are shown to be useful in identifying the cause of dose rate change brought on by the steel composition change. They can also be utilized in estimating the dose rate change brought on by the replacement of 316 SS with any new steel alloy with similar composition. 相似文献
109.
Mito I. Kitamura M. Kobayashi K. Murata S. Seki M. Odagiri Y. Nishimoto H. Yamaguchi M. 《Lightwave Technology, Journal of》1983,1(1):195-202
A new high-performance 1.3-μm InGaAsP semiconductor laser is described, in which effective current confinement into the active region has been realized. A p-n-p-n current blocking structure is made by liquid-phase epitaxy (LPE) on both sides of the active-stripe mesa which is defined by a pair of channels in the double-heterostructure wafer. The double-channel-planar-buried-heterostructure laser diodes (DC-PBH LD's) exhibit high-laser performances, such as a high differential quantum efficiency of 78-percent maximum, which results in high electrical to optical power conversion efficiency 43 percent, and high light output power of over 50 mW, as a result of the improvement in the current blocking structure. The threshold current temperature sensitivity is found experimentally to be reduced remarkably by increasing the doping concentration in the p-cladding layer. Characteristic temperature as high as 100 K has been obtained. CW operation is possible up to 130°C. 相似文献
110.
Seki K. Iwasaki M. Kawafuku M. Hirai H. Kishida K. 《Industrial Electronics, IEEE Transactions on》2009,56(3):628-634
A hybrid experimental system is one of the powerful tools to perform various seismic tests for unknown and/or huge structures, where an actuator-excited experimental vibratory system and a computational response analysis are simultaneously combined and implemented. This paper presents a control methodology for high-performance hybrid experimental systems. A 2-DOF control framework is applied from the viewpoint of control techniques, where a feedback compensator is designed according to the system stabilization analysis, and a feedforward (FF) compensator is designed to achieve the desired servo characteristics. In the FF compensator design, an iterative learning control approach is particularly adopted to eliminate the response delays in the hydraulic actuator. The proposed compensation algorithm has been verified using a laboratory hybrid experimental set up with two-mass structure as a load mechanism. 相似文献