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981.
982.
983.
Seung-Jun Yu Makoto Fujimaki Koichi Awazu Kimikazu Sasa 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2008,266(21):4762-4765
Reduction in polarization dependent loss of a planar lightwave circuit was achieved by asymmetric birefringence formed by ion implantation, in which oxygen ions were implanted along a diagonal of a cross-section of the planar lightwave circuit. The induced birefringence has a slow axis along the line perpendicular to the diagonal. In the present research, a decrease in polarization dependent loss of up to 3.7 dB was obtained, indicating that the method is effective for reducing polarization dependent loss. 相似文献
984.
Shiho Kanou Katsunori Nishimura Makoto Ichikawa Jirou Yoshida Yukoh Sakata Makoto Otsuka 《Drug development and industrial pharmacy》2013,39(7):771-780
In the presence of urea in solid states, the stability of unpulverized homosulfamine hydrate (phase I; UHH) is significantly decreased whereas that of unpulverized homosulfamine anhydrate (UHA) is not. The stability of UHH is decreased slightly more by pulverization (PHH). The major objective of this study was to investigate the effects of urea, dehydration, and pulverization on the stability of homosulfamine in solid states. Binary mixtures of UHH and urea, PHH and urea, and UHA and urea in a ratio of 1:1 (wt/wt) were prepared as physical mixtures and were analyzed by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), and Fourier transform infrared (FTIR) spectroscopy to study their appearance and structural changes before and after storage. PXRD analysis revealed that physical mixtures comprising UHH and urea and PHH and urea have the same diffraction pattern as that of the mixture of UHA and urea after preparation. The dehydration rate of the crystal water of UHH was accelerated by the presence of urea in addition to pulverization. Moreover, the PXRD patterns of the physical mixtures of UHH/urea and PHH/urea were significantly altered during storage, whereas that of UHA/urea was not, which was consistent with the SEM and FTIR results. The particle shape and appearance of UHH varied significantly as a result of pulverization. The stability of homosulfamine was influenced not only by the presence of urea and dehydration but also by the surface state and particle size of the crystalline form. 相似文献
985.
986.
Changes in the cycling of nitrogen, phosphorus, and potassium in a dairy farming system 总被引:1,自引:0,他引:1
Ryoji Kobayashi Akihisa Yamada Hiroyuki Hirooka Yusuke Tabata Jianguo Zhang Kazuhisa Nonaka Mikio Kamo Kiyoshi Hayasaka Yasuhiro Aoki Hidenori Kawamoto Hiroshi Shimonasako Tamaki Kida Masuhiro Ogawa Makoto Miyaji 《Nutrient Cycling in Agroecosystems》2010,87(2):295-306
The objective of this study was to quantify nitrogen (N), phosphorus (P), and potassium (K) use and cycling in a dairy farming system. The data were collected from the experimental farm at the National Institute of Livestock and Grassland Science in Tochigi Prefecture, Japan, using about 11 ha of forage crop fields and about 30 dairy cows. Forage crops grown in the field were ensiled and offered to the cows, and the subsequent compost from the animals’ excretion was applied to the field. The dairy farming system consisted of soil/crop, feed storage, animal, and compost components. Nutrient inputs and outputs and flows of the soil–plant–animal pathway for the whole farm and each component were measured for 5 years. Nutrient utilization was evaluated using nutrient balances, use efficiencies, and cycling indices. The 5 year average nutrient balances and nutrient use efficiencies of N, P, and K for the whole farm (kg ha?1 year?1) were 378, 97, and 199 and 0.25, 0.19, and 0.18, respectively. The characteristics of nutrient balances and use efficiencies for each component differed among N, P, and K. The average cycling indices of N, P, and K were 0.12, 0.11, and 0.37, respectively. Significant positive relationships between use efficiencies and cycling indices were observed in N and K. Year-to-year variations in flows were relatively large for compost application. The results suggested that improving N balance would be the most effective option for solving many of the environmental problems related to dairy farming. 相似文献
987.
Noriaki Hirose Yasuhisa Terachi Motohiro Kawafuku Makoto Iwasaki Hiromu Hirai 《Electrical Engineering in Japan》2011,175(2):63-73
This paper presents a novel method of initial value compensation (IVC) with additional input by considering the optimization of control input. IVC has been used to improve the control performance of various control systems with different initial values. Essential subjects, however, have still remained: in the conventional IVC approaches, the increases in the amplitude and number of high‐frequency components of the control input that accompany an increase in the control bandwidth could not be avoided. In this research, therefore, an optimization approach for control input is applied under the constraints of the conventional IVC approach. The effectiveness of the proposed approach has been verified by numerical simulations and experiments using a prototype. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(2): 63‐73, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21026 相似文献
988.
Kiyoshi Endo Noriyasu Kaneda Hidenori Waku Makoto Saitoh Nobuyoshi Emori 《乙烯基与添加剂工艺杂志》2001,7(4):177-183
Polymerizations of vinyl chloride (VC) with butyllithium (BuLi) and metallocene catalysts were investigated. In the polymerization of VC with BuLi, the activity for polymerization decreased in the following order; t‐BuLi > n‐BuLi > s‐BuLi. A polymer controlled structurally in the main chain was found to be synthesized from the polymerization of VC with BuLi. The molecular weights of polymers obtained in bulk polymerization were higher than those of polymers obtained in solution. A linear relationship of the Mn of the polymer and the polymer yields was observed. The Mw/Mn of the polymer did not change significantly during polymerization, although the Mw/Mn was around 2. Thermal stability of the polymer obtained with BuLi was higher than that of polymer obtained with radical initiators, as determined by TGA measurements. In the polymerization of VC with Cp*TiX3/MAO (X: Cl and OCH3) catalysts, polymers were obtained with both catalysts, although the rate of polymerization was slow. The Cp*Ti(OCH3)3//MAO catalyst in CH2Cl2 gave higher‐molecular‐weight polymers in a better yield than in toluene. From elemental analysis and the NMR spectra of the polymers, the Cp*Ti(OCH3)3/MAO catalyst gave polymers consisting of repeating regular head‐to‐tail units, in contrast to the Cp*TiCl3/MAO catalyst, which gave polymers having anomalous units. 相似文献
989.
We consider the problenl of const,ructing a fixed-size confidence region for a linear functioll of mean vectors of k multinormal populations. The covariance matrices are assunlcd to be known except for the unknown scalar multipliers. A two-stage procedure is proposed to derive such a confidence region. We also discuss the asylnptotic efficiency of the procedure. 相似文献
990.
Toshiaki Rokunohe Tatsuro Kato Makoto Hirose Tetsu Ishiguro 《Electrical Engineering in Japan》2010,171(1):19-27
Efforts of designers of gas‐insulated switchgear (GIS) are currently focused on such features as smaller installation area and economical efficiency. Circuit breakers (CB), disconnecting switches (DS), and earthing switches (ES) have been redesigned in more compact configurations. Compactness and light‐weight requirements are applied also to bushings used in GIS. GIS bushings can be divided in three general types: capacitor, gas‐filled, and molded bushings. Requirements of the light weight and the economical efficiency of gas‐filled bushings can be satisfied by improvements in insulation technology. Size reduction can be effectively achieved by moderation of the electric field strength on the outside surface of the hollow insulator in the area of the inner grounded electrode tip. We devised a new inner grounded electrode structure consisting of a cylindrical electrode and a ring electrode supported by column electrodes. This paper describes the effect of reduction of the maximum value of electric field strength on the outside surface of the hollow insulator by a new type of grounded electrode. Then, improvement of insulation performance for electrodes with insulation coating in SF6 gas is described as the composite insulation technology. Finally, the efficiency of these insulation technologies is described by the basic insulation test results of a prototype compact 800‐kV SF6 gas‐filled bushing. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(1): 19–27, 2010; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/eej.20898 相似文献