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排序方式: 共有388条查询结果,搜索用时 31 毫秒
101.
An apparatus to pasteurize soybean milk using radio-frequency flash heating (RF-FH) was developed. An electrode surface was covered with a 50-μm thick Teflon film, and 28 MHz RF-FH was applied to soybean milk flowing through the electrode. 相似文献
102.
Modeling the electron field emission from carbon nanotube films. 总被引:3,自引:0,他引:3
A theoretical framework for the electron field emission from carbon nanotubes (CNTs) is discussed. Using the tunneling theory, the influence of the detailed electron energy dispersion is proven to be of little importance for the electron field emission. By means of numerical computations in a simplified model, the influence of the environment on the local field on a CNT is discussed for an aligned CNT film. In a simple triangular model for the potential energy barrier at the tube end, a tunneling probability was obtained. A statistical model was developed for the structural and functional parameters of aligned CNT films. Practical CNT films of excellent alignment, obtained directly on a tungsten wire by plasma-enhanced chemical vapor deposition, were analyzed by this statistical model. Their distribution in the enhancement factors was thus deduced. An indirect method to get the average electrical parameters of the film using only a limited amount of experimental data was thus established. 相似文献
103.
Tatsuya Kume Masanori Satoh Tsuyoshi Suwada Kazuro Furukawa Eiki Okuyama 《Precision Engineering》2013,37(4):825-830
A precise inclinometer (Talyvel 4) was adopted for evaluating aligning straightness of the first 71 m of the KEK electron/positron injector linear accelerator (linac). The straightness could be evaluated with a standard deviation of less than 49 μm. It is in good agreement with those obtained using a conventional alignment telescope and our laser-based alignment system.Error estimation based on the rules of error propagation shows that shape evaluation with a standard deviation of 0.3 mm for a distance of 500 m can be achieved using the proposed method. It indicates that this method is suitable for evaluating straightness of several hundred meters of linacs with sub-millimeter of accuracy. 相似文献
104.
Muhammad Miftahul Munir Asep Suhendi Takashi Ogi Ferry Iskandar Kikuo Okuyama 《Advanced Powder Technology》2013,24(1):143-149
This paper reports the systematic investigation of ion-induced nucleation rate measurement in a SO2/H2O/N2 gas mixture, employing soft X-ray at different pressure and temperature levels. Experiments were conducted using a modified continuous flow gas-generation system employing a soft X-ray ionizer and a particle counter, with an improved integrated online temperature, pressure and a relative humidity (RH) control system. Nucleation rates were measured as a function of SO2 concentration at different levels of RH, pressure (600–970 hPa) and temperature (5–25 °C). The results show that the nucleation rate dependence on SO2 concentration followed a power law, and the slope varied slightly in a range from 1 to 1.26 at different RH levels (15–60%). A positive pressure effect was generally found and a power law was followed with varied scaling for different SO2 concentrations. The trend of an increase in nucleation rate with temperature was consistent with observations in homogenous nucleation experiments, and with the behavior predicted by classical binary nucleation theory. These experimental results will be useful to explain the contribution of ion-induced nucleation in different locations and atmospheric conditions. 相似文献
105.
Shinji Sugihara Ryuji Hori Hitomi Nakanowatari Yasuhiro Takada Isao Yumoto Naoki Morita Yutaka Yano Kazuo Watanabe Hidetoshi Okuyama 《Lipids》2010,45(2):167-177
A very long chain polyunsaturated hydrocarbon, hentriacontanonaene (C31:9), was detected in an eicosapentaenoic acid (EPA)-producing
marine bacterium, which was isolated from the mid-latitude seashore of Hokkaido, Japan, and was tentatively identified as
mesophilic Shewanella sp. strain osh08 from 16S rRNA gene sequencing. The geometry and position of the double bonds in this compound were determined
physicochemically to be all cis at positions 3, 6, 9, 12, 15, 19, 22, 25, and 28. Although C31:9 was detected in all of the seven EPA- or/and docosahexaenoic
acid-producing bacteria tested, an EPA-deficient mutant (strain IK-1Δ8) of one of these bacteria had no C31:9. Strain IK-1Δ8
had defects in the pfaD gene, one of the five pfa genes responsible for the biosynthesis of EPA. Although Escherichia
coli DH5α does not produce EPA or DHA inherently, cells transformed with the pfa genes responsible for the biosynthesis of EPA and DHA produced EPA and DHA, respectively, but not C31:9. These results suggest
that the Pfa protein complex is involved in the biosynthesis of C31:9 and that pfa genes must not be the only genes responsible for the formation of C31:9. In this report, we determined for the first time
the molecular structure of the C31:9 and discuss the possible biosynthetic pathways of this compound. 相似文献
106.
Conventional multi-zonal ventilation measurement methods by multiple types of perfluorocarbon tracers use a number of different gases equal to the number of zones (n). The possible n×n+n airflows are estimated from the mass balance of the gases and the airflow balance. However, some airflows may not occur because of inter-zonal geometry, and the introduction of unnecessary, unknown parameters can impair the accuracy of the estimation. Also, various error factors often yield an irrational negative airflow rate. Conventional methods are insufficient for the evaluation of error. This study describes a way of using the least-squares technique to improve the precision of estimation and to evaluate reliability. From the equations’ residual, the error variance–covariance matrix Λq of the estimated airflow rate error is deduced. In addition, the coefficient of determinant using the residual sum of squares and total variation is introduced. Furthermore, the error matrix mΛq from the measurement errors in the gas concentration and gas emission rate is deduced. The discrepancy ratio of the model premises is defined by dividing the diagonal elements of the former by those of the latter. Moreover, the index of irrationality of the estimated negative airflow rate is defined, based on the different results of the three estimation methods. Some numerical experiments are also carried out to verify the flow rate estimation and the reliability evaluation theory. 相似文献
107.
Kumagai T Shiotari A Okuyama H Hatta S Aruga T Hamada I Frederiksen T Ueba H 《Nature materials》2012,11(2):167-172
Hydrogen bonds are the path through which protons and hydrogen atoms can be transferred between molecules. The relay mechanism, in which H-atom transfer occurs in a sequential fashion along hydrogen bonds, plays an essential role in many functional compounds. Here we use the scanning tunnelling microscope to construct and operate a test-bed for real-space observation of H-atom relay reactions at a single-molecule level. We demonstrate that the transfer of H-atoms along hydrogen-bonded chains assembled on a Cu(110) surface is controllable and reversible, and is triggered by excitation of molecular vibrations induced by inelastic tunnelling electrons. The experimental findings are rationalized by ab initio calculations for adsorption geometry, active vibrational modes and reaction pathway, to reach a detailed microscopic picture of the elementary processes. 相似文献
108.
109.
In this paper we reexamine the possibility of using ferroelectric materials for adaptive learning artificial intelligence
applications, by exploiting their capability to be set in electrically-controlled multivalue polarization states. Our experiments
on a Pb(Zr,Ti)O3 ceramic sample consisted in conveniently selecting the input pulse electric field and temperature of the sample during field
application, in order to create partially-switched states. Employing strong/weak electric field pulses allows to control the
analog polarization levels by a linear or logarithmic addition of pulses. The partially-switched states are mapped with enhanced
resolution when domains with dissimilar evolution stages are present. Applying electric fields while heating the sample allows
to reduce the switching time and shifts down the switching threshold. Thus, in addition to artificial intelligence applications,
these results provide hints for energy-saving devices that exploit the intrinsic high mobility of small fluctuating domains. 相似文献
110.
Motohiro Kawafuku Kazuhiro Otsu Makoto Iwasaki Hiromu Hirai Masahito Kobayashi Atsushi Okuyama 《Electrical Engineering in Japan》2007,159(1):54-61
The paper proposes a high‐precision simulator for the following mode system design in hard disk drives (HDDs). The simulator is composed of two models: one is a precise mechanical plant which includes numerous high‐frequency vibration modes, and the other is a disturbance signal model which is separated into various disturbances. In the proposed approach, a differential iteration method is applied to identify the precise mechanical plant, providing accurate experimental model analyses. The effectiveness of the synthesized simulator was verified by the comparative studies for experiments and numerical simulations. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 159(1): 54–61, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20457 相似文献