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排序方式: 共有938条查询结果,搜索用时 15 毫秒
61.
Meisen Li Yoshiyuki Bando Ryo Tanigawara Toru Kamiya Keiji Yasuda Masaaki Nakamura 《加拿大化工杂志》2001,79(4):602-607
The effects of operation conditions on the flow behaviour in gas–liquid countercurrent trickle bed biofilter were experimentally examined. In order to prevent gas channelling in the biofilter, packings with a relatively large void fraction, which have a role to maintain a high void fraction in the bed, were added. The gas and liquid velocities of the packed structure and the packings were changed, and the residence time distributions (RTDs) of the gas and liquid were measured. It was found that the addition of void supporters was very effective in the suppression of gas channelling. 相似文献
62.
63.
This study examined the applicability of the theory of elastic membranes to the inflation deformation of knitted fabrics. Membrane theory was developed originally for the inflation deformation of a uniform and isotropic rubber membrane. The theory was composed of several equations that related extension ratio and biaxial stress in the equilibrium state of a membrane. Those equations needed numerical analysis since they could not be solved analytically. Although knitted fabrics had mechanical anisotropy due to the directions of wale and cource, numerical analysis could be carried out when the biaxial stresses of fabrics were expressed by the involution equations of extension ratio. In experimentation, a knitted fabric layered on a rubber sheet was inflated spherically by air pressure, then internal pressure, and the deformation were measured. From the experimental results it was concluded that the membrane theory could predict the inflation deformation of knitted fabrics like the burst test, and so on. 相似文献
64.
Yoshihiro Itoh Fumiya Sahara Kaori Ozaki Ryo Akasaka Akira Teramoto 《Polymer Bulletin》2011,67(8):1455-1462
Emulsion polymerizations of several vinyl monomers, styrene, methyl methacrylate, butyl methacrylate, butyl acrylate, and
vinyl acetate, in water using alkali–hydrolysable cationic surfactants with a betaine ester group (1-alkoxycarbonylmethyl)trimethylammonium
chlorides, as emulsifiers were carried out and properties of the resulting latices and the polymers recovered by hydrolysis
and salting out were investigated. There were little influences of the surfactants and monomers used here on the polymerizations,
forming stable and monodisperse latices with a mean diameter of ca. 70 nm and giving a high molecular weight of polymers at
high yields. All polymers were precipitated and recovered by adding a small amount of sodium hydroxide into the latex solutions
contained little amount of ionic species. Solvent-cast films of the polymers were found to have surfaces as hydrophobic as
those for the corresponding pure polymers prepared by bulk polymerization. 相似文献
65.
KyoungHou Kim Ryo Aida YoungAh Kang Yutaka Ohkoshi Yasuo Gotoh Masanobu Nagura Hiroshi Urakawa 《Polymer》2009,50(19):4429-4431
The structure development in the continuous laser-heated drawing process of poly(ethylene 2,6-naphthalene dicarboxylate) (PEN) fiber was analyzed by in-situ X-ray diffraction measurement. Because of the rapid and uniform laser heating, and the resultant steady-state nature of the necking-drawing, the structure development after the on-set of necking could be measured in the time resolution of several hundred microseconds. We found for the first time the temporal appearance of meridional (001′) diffraction at several milliseconds after the on-set of necking indicating that the mesophase structure similar to the one reported for poly(ethylene terephthalate) was also formed in the initial stage of fiber structure development of PEN. The d-spacing of the (001′) diffraction 1.230 ± 0.003 nm was shorter than the c-axis lengths of both α and β crystals. 相似文献
66.
Ryuichi Tayama Katsumi Hayashi a Ryo Iwasaki Masana Sasaki Yoshinori Etoh Hiroshi Sakurai 《Nuclear Engineering and Design》2001,210(1-3):239-248
A neutron-scanning device was developed for measuring accurate neutron densities of BWR high burn-up fuels up to 65 GWd tU−1. Characteristic test of this device was done with a 252Cf source and adopted to measure axial distributions of neutron densities of BWR spent fuels with various enrichments (2.0–3.4%), which had been irradiated up to 60 GWd tU−1 at Fukushima Daini Nuclear Power Station Unit 2(2F-2). We found the measured neutron densities were proportional to about fourth power of the corresponding burn-up values. The neutron densities calculated by the ORIGEN2.1 code and various cross section libraries showed good agreements with the measured ones in profile and absolute value except for BWR-UE file mainly based on ENDF/B-IV. The BS240J32 library based on JENDL3.2 was the best among the investigated libraries. 相似文献
67.
Yoshitomo Masuda Norio Nihei Ryo Sakurai Reiji Hattori 《Journal of the Society for Information Display》2006,14(5):443-448
Abstract— A novel reflective display [Quick‐Response Liquid Powder Display (QR‐LPD®)], has been developed. This paper‐like display has the advantages of outstanding image stability, easy viewing, low‐power consumption, and a high‐response time. QR‐LPD® will be promoted, initially, for use as electronic price‐tag displays for merchandise. In addition, QR‐LPD® is suitable for flexible display applications because it does not require TFT arrays or a high‐temperature process while maintaining an excellent paper‐like image as well as glass‐type display compatibility. 相似文献
68.
An Experimental Study of a Cooperative Positioning System 总被引:3,自引:3,他引:0
Several position identification methods are being used for mobile robots. Dead reckoning is a popular method but due to the error accumulation from wheel slippage, its reliability is low for measurement of long distances especially on uneven surfaces. Another popular method is the landmark method, which estimates current position relative to known landmarks, but the landmark method's limitation is that it cannot be used in an uncharted environment. Thus, this paper proposes a new method called Cooperative Positioning System (CPS) that is able to overcome these shortcomings. The main concept of CPS is to divide the robots into two groups, A and B where group A remains stationary and acts as a landmark while group B moves and then group B stops and acts as a landmark for group A. This process is repeated until the target position is reached. Compared with dead reckoning, CPS has a far lower accumulation of positioning errors, and can also work in three dimensions. Furthermore, CPS employs inherent landmarks and therefore can be used in uncharted environments unlike the landmark method. In this paper, we introduce the basic concept of CPS and its positioning principle. Next, we outline a second prototype CPS machine model (CPS-II) and discuss the method of position estimation using the variance of positioning error and weighted least squares method. Position identification experiments using the CPS-II model give a positioning accuracy of 0.12% for position and 0.32 degree for attitude after the robots traveled a distance of 21.5 m. 相似文献
69.
A new one-atomic layer ZrO2/ZSM-5 hybrid catalyst was prepared by using the repeated reactions between Zr(OC2H5)4 and of the OH groups of the external surfaces of ZSM-5, followed by calcination. The one-atomic layer ZrO2 attached on the ZSM-5 surface was characterized by means of X-ray diffraction, X-ray fluorescence and EXAFS. The ZrO2 overlayer is suggested to epitaxially grow on the ZSM-5(001) plane in a [111] direction of tetragonal ZrO2. The one-atomic layer ZrO2/ZSM-5 is a unique catalyst which produces selectively isopentane from CH3OH. 相似文献
70.
Speckle reduction in coherent information processing 总被引:3,自引:0,他引:3
Iwai T. Asakura T. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1996,84(5):765-781
Speckle reduction techniques have been developed as one of the most active research fields in coherent optical information processing, together with the investigations of speckle statistics and coherence theory. The principles of speckle reduction are classified to five categories: 1) control of spatial coherence, 2) control of temporal coherence, 3) spatial sampling, 4) spatial averaging, and 5) digital image processing. This paper surveys the research works in the field of speckle reduction techniques involving four categories 1)-4) which have been conducted in the past 30 years 相似文献