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排序方式: 共有678条查询结果,搜索用时 15 毫秒
51.
N. L. Weinberg G. M. Blank H. A. Aulich A. Kentaro Hoffmann T. B. Reddy 《Journal of Applied Electrochemistry》1973,3(3):227-230
An electrochemical method has been developed for bonding electrically-conductive adherends. The procedure is based on the electrochemical generation of a curing agent from an otherwise chemically-unreactive precursor mixed with an epoxy resin sandwiched between the bonding members. The one-part epoxy resin is storage stable and cured rapidly on passage of current. 相似文献
52.
Friend J Nakamura K Ueha S 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2004,51(7):871-878
A torsional microtransducer for high-power applications was developed using standard bulk lead zirconium titantate (PZT) placed upon a small rectangular prism made from phosphor bronze, with a tapered conical end serving as a horn and a machined interior to improve the actuator's response. Torsion was obtained from a prototype at the design frequency of 192 kHz as well as over a wide range of frequencies from 136 kHz to 1.02 MHz. Torsional vibration velocities of 335 mm/s at 192 kHz were measured at 27.3 V(RMS) on the 1.5-mm diameter output tip, amounting to 25,600 degree/s vibration velocity along the outer circumference of the tip. At 1.02 MHz, a torsional vibration velocity of 1750 mm/s (134,000 degree/s) at 17.8 V(RMS) was obtained through use of the thickness mode of the PZT elements. Using the design described in this study, high-power torsional transducers with diameters of 5 mm and below are now possible. 相似文献
53.
An aqueous suspension system for phospholipase D-mediated synthesis of PS without toxic organic solvent 总被引:3,自引:2,他引:1
Yugo?Iwasaki Yukiko?Mizumoto Takahiro?Okada Takaya?Yamamoto Kentaro?Tsutsumi Tsuneo?YamaneEmail author 《Journal of the American Oil Chemists' Society》2003,80(7):653-657
Enzymatic synthesis of PS by phospholipase D (PLD)-mediated transphosphatidylation in an aqueous media was investigated. The
purpose of this study was to establish a novel synthetic method where no toxic organic solvents were used. An attempt to react
soybean lecithin (simply dispersed in an aqueous buffer) with an aqueous solution of l-serine and PLD was unsuccessful, giving only 20% of PS. By contrast, a suspension of lecithin adsorbed on fine powders such
as silica was effectively converted into PS in an aqueous solution of l-serine and PLD. After screening various powders for use as the lecithin adsorbent, calcium sulfate was found to be the best
with respect to lecithin conversion. In addition, calcium sulfate did not require prior adsorption of lecithin (i.e., the
reaction proceeded effectively simply by adding the powder to an aqueous mixture of lecithin, l-serine, and PLD). With this “aqueous suspension system” of calcium sulfate, up to 180 mg/mL lecithin was completely converted,
resulting in more than 80% PS in 24 h. The synthesized PS could easily be recovered from the powder by extracting with a mixture
of n-hexane, ethanol, and diluted HCl. 相似文献
54.
A single-element tuning fork piezoelectric linear actuator 总被引:1,自引:0,他引:1
Friend JR Satonobu J Nakamura K Ueha S Stutts DS 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2003,50(2):179-186
This paper describes the design of a piezoelectric tuning-fork, dual-mode motor. The motor uses a single multilayer piezoelectric element in combination with tuning fork and shearing motion to form an actuator using a single drive signal. Finite-element analysis was used in the design of the motor, and the process is described along with the selection of the device's materials and its performance. Swaging was used to mount the multilayer piezoelectric element within the stator. Prototypes of the 25-mm long bidirectional actuator achieved a maximum linear no-load speed of 16.5 cm/s, a maximum linear force of 1.86 N, and maximum efficiency of 18.9%. 相似文献
55.
56.
Kentaro Yanagihara Jumpei Taketsugu Kiyoshi Fukui Shigeru Fukunaga Shinsuke Hara Ken-ichi Kitayama 《Wireless Personal Communications》2007,40(3):401-415
In this paper, we propose a new energy efficient clustering scheme with transmission power control named “EACLE” (Energy-Aware
CLustering scheme with transmission power control for sEnsor networks) for wireless sensor networks, which are composed of
the following three components; “EACLE clustering” is a distributed clustering method by means of transmission power control,
“EACLE routing” builds a tree rooted at a sink node and sets the paths from sensor nodes taking energy saving into consideration,
and “EACLE transmission timing control” changes the transmission timing with different levels of transmission power to avoid
packet collisions and facilitates packet binding.
With an indoor wireless channel model which we obtained from channel measurement campaigns in rooms and corridors and an energy
consumption model which we obtained from a measurement of a chipset, we performed computer simulations to investigate the
performance of EACLE in a realistic environment. Our simulation results indicate that EACLE outperforms a conventional scheme
such as EAD (Energy-Aware Data-centric routing) in terms of communication success rate and energy consumption. Furthermore,
we fully discuss the impact of transmission power and timing control on the performance of EACLE. 相似文献
57.
Hideki Kokame Kentaro Hirata Keiji Konishi Takehiro Mori 《International journal of control》2013,86(6):537-546
Supposing a non-linear system is subjected to parametric uncertainties, the present paper aims at stabilizing its unstable steady states. A distinctive feature of the problem is that exact information about the steady state is unavailable. To cope with the difficulty, we have examined the applicability of the state difference feedback which uses the difference between the present state x(t) and the past state x(t-T). A rigorous stability analysis has been executed for the case where state deviations are controllable by a single input variable. The stability analysis has led to a favourable conclusion that if the number of unstable modes is just two, and if they are not associated with the origin in the complex plane, we are always able to find a controller which stabilizes the deviations from the unknown steady state. Design process is illustrated by using two kinds of pendulum systems. 相似文献
58.
We present a method for combining two bilingual dictionaries to make a third, using one language as a pivot. In this case
we combine a Japanese-English dictionary with a Malay-English dictionary, to produce a Japanese-Malay dictionary. Our method
differs from previous methods in its improved matching through normalization of the pivot language. We have made a prototype
dictionary of around 76,000 Japanese-Malay pairs for 50,000 Japanese head words. 相似文献
59.
Tomoya Nagira Shugo Morita Hiroyoshi Yokota Hideyuki Yasuda Christopher M. Gourlay Masato Yoshiya Akira Sugiyama Kentaro Uesugi Akihisa Takeuchi Yoshio Suzuki 《Metallurgical and Materials Transactions A》2014,45(12):5613-5623
Synchrotron X-ray radiography at 125 frames per second was used to study deformation mechanisms in semi-solid Fe-C alloys at high solid fraction and shear strain rates of 10?1/s. An image correlation approach was also used to quantify the shear strain fields and study shear-induced dilation and the origin of shear cracking. It was shown that, at high solid fraction (90 to 93 pct solid), rearrangement including rotation and translation of solid particles became restricted and shear strain localized into narrow liquid-filled channels/fissures. Shear cracking was shown to originate from inadequate liquid flow into the expanding spaces between solid particles caused by shear-induced dilation. At lower solid fraction (~85 pct solid), solid particles rearranged with a significantly higher component of rotation leading to more shear-induced dilation and a wider shear band. 相似文献
60.
Shigeo Yamabe Kazuo Kobayashi-Hattori Kentaro Kaneko Hiroshi Endo Toshichika Takita 《Food chemistry》2007,100(1):369-374
To clarify the effect of soybean varieties on isoflavone, a useful component for human health, in soybean products, we investigated changes in the isoflavone content and composition in rice-koji miso, after fermentation/aging for 6 or 12 months using varieties of soybeans (Tohoku-126, Tohoku-135, Tohoku-139, Suzuyutaka and Chinese soybeans), by high performance liquid chromatography. In soybeans, the total isoflavone content in Tohoku-126 was 444 mg/100 g, which was 1.2–2.0 times the content in the other soybean varieties. The malonyl glycosides and aglycones in soybeans accounted for more than 60% and only a few percent, respectively. As for rice-koji miso, the total isoflavone and aglycone contents were the highest in miso prepared from Tohoku-126. The ratios of glycosides to aglycones (80.1–92.6%) in miso were higher than those in the original soybeans. The time course of the isoflavone composition during the fermentation/aging process of rice-koji miso indicated that glycosides decreased from 86.4% to 44.9% after 6 months but aglycones increased from 9.6% to 53.3%. 相似文献