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排序方式: 共有1303条查询结果,搜索用时 15 毫秒
81.
Takao Shibusawa 《Coloration Technology》1980,96(6):293-296
Three polynomial approximations to Wilson's equation were derived by means of Hastings's method. One of them is an approximation to Crank's equation with 3–figure accuracy and it approximates to Wilson's epuation very closely for high values of fractional equilibrium exhaustion (E), E > 0. 95. Two other polynomials approximate to Wilson's equation very well in the ranges 0. 95 > EX). 76 and 0. 76 > E > 0. 30 respectively. The polynomials derived here only include up to second order terms, so that by using the equations which are obtained by solving the polynomials for diffusion coefficient (D), D can easily be calculated from experimental dye uptake data. By using the polynomial approximation, the changes in rate–of–dyeing of a non–ionic dye on a nylon 6 fibre by addition of a dispersing agent were calculated. Results of the experiment agreed well with the calculated. 相似文献
82.
Takao Kato 《Applicable Algebra in Engineering, Communication and Computing》2003,13(6):475-484
In [1], Homma-Kim-Yoo showed that a code C such that the support of the associated projective system is a union of two linear subspaces, is uniquely determined up to
equivalence by its weight enumerator. Let W
C
(z) be the weight enumerator of a code C. Assuming certain conditions on the coefficients of W
C
(z) for some range, we prove that the support of the associated projective system is a union of two linear subspaces.
Received: February 27, 2002; revised version: October 2, 2002
Keywords: Linear code, Projective system, Weight enumerator.
MSC2000: 94B27, 94B65, 51E20 Partially supported by Grant-in-Aid for Scientific Research, Ministry of Education, #12640180 相似文献
83.
Kimihiro Yamashita Motohide Matsuda Yasushi Inda Takao Umegaki Masayuki Ito Toshinori Okura 《Journal of the American Ceramic Society》1997,80(7):1907-1909
Dielectric depression and dispersion were observed in BaTiO3 ceramic films fabricated by electrophoretic deposition followed by sintering. The dielectric constants were depressed down to 6800–4600 around the Curie point ( T C ). The dielectric dispersion occurred above T C . These dielectric properties are attributable to a surface layer formed during sintering. XRD analysis indicated that the surface layer was a hexagonal-like BaTiO3 phase. A mixed solvent of acetylacetone and alcohol employed in the present work may have been responsible for the formation of the surface layer. 相似文献
84.
Analytical investigation of two different absorption modes: falling film and bubble types 总被引:1,自引:0,他引:1
The objectives of this paper are to analyze a combined heat and mass transfer for an ammonia–water absorption process, and to carry out the parametric analysis to evaluate the effects of important variables such as heat and mass transfer areas on the absorption rate for two different absorption modes — falling film and bubble modes. A plate heat exchanger with an offset strip fin (OSF) in the coolant side was used to design the falling film and the bubble absorber. It was found that the local absorption rate of the bubble mode was always higher than that of the falling film model leading to about 48.7% smaller size of the heat exchanger than the falling film mode. For the falling film absorption mode, mass transfer resistance was dominant in the liquid flow while both heat and mass transfer resistances were considerable in the vapor flow. For the bubble absorption mode, mass transfer resistance was dominant in the liquid flow while heat transfer resistance was dominant in the vapor region. Heat transfer coefficients had a more significant effect on the heat exchanger size (absorption rate) in the falling film mode than in the bubble mode, while mass transfer coefficients had a more significant effect in the bubble mode than in the falling film mode. 相似文献
85.
Masaaki Bannai Yasushi Tomita Yasushi Ishida Takahiko Miyazaki Atsushi Akisawa Takao Kashiwagi 《Energy》2007
Energy service business, or energy service company (ESCO), is expanding among industrial users as a means of energy saving. The ESCO business normally tends to become a long-term operation. During the operation, fluctuations of fuel and electricity costs significantly impact on the stability of the profit from ESCO business. Therefore, it is essential to reduce the risk of fuel and electricity cost fluctuations. Generally, a transaction called “financial derivative” is used as a measure of hedging against the fuel price fluctuation. In the case of ESCO business, it is necessary to manage the risk of both electricity and fuel price fluctuations because the variation in electricity price strongly affects the profit from ESCO as that in fuel price does. 相似文献
86.
Akira Fukuda Hirokazu Takenaka Takao Mizusaki 《Journal of Low Temperature Physics》2000,121(5-6):737-742
We have been searching for two-dimensional (2-D) superfluidity of spin-polarized atomic hydrogen (H) adsorbed on liquid helium surface. We have investigated H adsorbed on
3
He-
4
He mixtures instead of pure
4
He because the thermal coupling of H to the mixtures is stronger than
4
He. ESR at 129 GHz was carried out to detect H at 4.5 T by using the Fabri-Perot confocal cavity with the cold spot located at the confocal point and thus the 2-D H signal was effectively detected. We investigated the two-body bulk and surface recombination processes of H on a 3%
3
He
3
He-
4
He mixture film. From the analysis of the surface recombination process, we found the adsorption energy of H was a 0.6 K for the mixture film in the temperature range between 120 mK and 250 mK, greater than the 0.3–0.4 K found previously for pure
3
He and a 67%
3
He
3
He-
4
He mixture. 相似文献
87.
N‐Phenylmaleimide–N‐(p‐hydroxy)phenylmaleimide–styrene terpolymer (HPMS), carrying reactive p‐hydroxyphenyl groups, was prepared and used to improve the toughness of cyanate ester resins. Hybrid modifiers composed of N‐phenylmaleimide–styrene copolymer (PMS) and HPMS were also examined for further improvement in toughness. Balanced properties of the modified resins were obtained by using the hybrid modifiers. The morphology of the modified resins depends on HPMS structure, molecular weight and content, and hybrid modifier compositions. The most effective modification of the cyanate ester resin was attained because of the co‐continuous phase structure of the modified resin. Inclusion of the modifier composed of 10 wt% PMS (Mw 136 000 g mol?1) and 2.5 wt% HPMS (hydroxyphenyl unit 3 mol%, Mw 15 500 g mol?1) led to 135% increase in the fracture toughness (KIC) for the modified resin with a slight loss of flexural strength and retention of flexural modulus and glass transition temperature, compared with the values for the unmodified resin. Furthermore, the effect of the curing conditions on the mechanical and thermal properties of the modified resins was examined. The toughening mechanism is discussed in terms of the morphological and dynamic viscoelastic behaviour of the modified cyanate ester resin system. © 2001 Society of Chemical Industry 相似文献
88.
Yoko Inui Takao Itioka Kaori Murase Ryohei Yamaoka Takao Itino 《Journal of chemical ecology》2001,27(10):2029-2040
The partnership in the Crematogaster–Macaranga ant–plant interaction is highly species-specific. Because a mutualistic relationship on a Macaranga plant starts with colonization by a foundress queen of a partner Crematogaster species, we hypothesized that the foundress queens select their partner plant species by chemical recognition. We tested this hypothesis with four sympatric Macaranga species and their Crematogaster plant-ant species. We demonstrated that foundress Crematogaster queens can recognize their partner Macaranga species by contact with the surface of the seedlings, that they can recognize compounds from the stem surface of seedlings of their partner plant species, and that the gas chromatographic profiles are characteristic of the plant species. These findings support the hypothesis that foundress queens of the Crematogaster plant-ant species select their partner Macaranga species by recognizing nonvolatile chemical characteristics of the stem surfaces of seedlings. 相似文献
89.
Takao Kume Yoichi Ikeda Takaya Iseki Hisataka Yakabe Hiroyuki Tanaka Hideaki Hikosaka Yasuhiro Takagi Masaya Ito 《International Journal of Hydrogen Energy》2013
We have been developing a hydrogen production module with a Pd-based membrane on catalyst (MOC) from natural gas. The MOC module is expected to be more compact and cheaper than the conventional hydrogen production module. To evaluate the hydrogen production performance of the MOC module and to clear the factor that dominates the effective hydrogen production, we compared the reforming performance of the catalytic support without hydrogen permeable membrane and the MOC module at various reaction conditions. As a result, it was cleared that hydrogen permeation through the membrane improves the methane conversion drastically in the MOC module by comparing with the support only module and changing the experimental conditions. 相似文献
90.
Takao Kobayashi 《Engineering Fracture Mechanics》2010,77(12):2370-2384
In the late 1970s, Dr. George Irwin suggested to his colleagues at the University of Maryland that valuable information about a fracture event was recorded in fracture surface topography. Under his urging, Takao Kobayashi, an associate professor at the time, began quantifying and interpreting topographical features. Over the subsequent 30 years the procedures for quantifying and interpreting fracture surface topography grew continuously into an established technology that allows a fracture event to be reconstructed in microscopic detail. FRASTA (fracture surface topography analysis) has now been applied to achieve solutions to a wide variety of failure problems. This paper chronicles the historical development of FRASTA, recounts several notable achievements, and presents the plan for further development and future applications. 相似文献