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31.
Prediction model of surface residual stress within a machined surface by combining two orthogonal plane models 总被引:2,自引:1,他引:2
Hiroyuki Sasahara Toshiyuki Obikawa Takahiro Shirakashi 《International Journal of Machine Tools and Manufacture》2004,44(7-8):815-822
The variation of surface residual stress within a machined surface layer caused by face turning was studied. The size of the tool’s corner radius and the feed rate affect residual stress. A process model using the finite element method is proposed and the mechanical effects of the corner radius and feed rate on a machined surface were discussed. When a tool with a small corner radius is used, surface residual stress perpendicular to the cutting direction becomes compression stress. As well, surface residual stress changes from tension to compression as the feed rate decreases. The process model consists of an orthogonal cutting simulation and an indentation-like simulation of a corner radius into a work piece surface. The simulated results show quantitative agreement with the residual stress measured experimentally. The integrity of the machined surface will be controlled more efficiently if the cutting conditions during finishing are determined with the proper consideration of the surface generating process. 相似文献
32.
Mutsumu Fukada Kiyotaka Kinoshita Toshiyuki Kajioka 《Journal of the Society for Information Display》2016,24(5):307-311
Abstract — This paper proposes a new process to manufacture cover glass that overcomes a strength trade‐off between the face and the edge. In the process, alkali barrier films are deposited on glass faces before an ion exchange process in order to control face stress properties without inhibiting the edge strengthening. As a demonstration of the process, alkali‐alumino‐silicate glass sheets with sputter‐deposited SiO2 films were chemically strengthened, and then their stress properties and strengths were investigated. As a result, thicker SiO2 films cause lower face DOL (depth of strengthened layer), and it is observed that the faces have lower DOL than the edges. In strength tests corresponding to major fracture modes of smartphone cover glass, specimens with 80–100 nm films have more balanced face performance and better edge impact strengths than the no‐film specimen. 相似文献
33.
Watabe H Hatazawa J Ishiwata K Ido T Itoh M Iwata R Takahashi T Hatano K Nakamura T 《IEEE transactions on medical imaging》1995,14(4):688-696
We proposed a new method (;linearized method') to analyze neuroleptic ligand-receptor specific binding in a human brain using positron emission tomography (PET). We derived the linear equation to solve four rate constants, k(3), k(4), k(5), k(6) from PET data. This method does not demand a radioactivity curve in plasma as an input function to the brain, and can perform fast calculations in order to determine rate constants. We also tested the nonlinearized method including nonlinear equations which is a conventional analysis using plasma radioactivity corrected for ligand metabolites as an input function. We applied these methods to evaluate dopamine D(2) receptor specific binding of [(11)C] YM-09151-2. The value of B(max)/K(d)=k(3)/k (4) obtained by the linearized method was 5.72+/-3.1 which was consistent with the value of 5.78+/-3.4 obtained by the nonlinearized method. 相似文献
34.
Fumitaka Tsukihashi Toshiyuki Hatta Eiji Tawara 《Metallurgical and Materials Transactions B》1996,27(6):967-972
The deoxidation equilibrium of molten titanium and titanium-aluminum alloys saturated with solid CaO has been measured in the temperature range from 1823 to 2023 K. The equilibrium constant of reaction CaO (s)=Ca (mass pct in Ti,Ti-Al)+O (mass pct in Ti,Ti-Al) and the interaction parameter between calcium and oxygen were determined for Ti, TiAl, and TiAl3. The standard Gibbs energy of reaction for TiAl was obtained as follows: $$\Delta G^\circ = 279,000 - 103TJ/mol$$ The possibilities for the deoxidation of titanium and titanium-aluminum alloys by using calcium-based fluxes are discussed. 相似文献
35.
The Vertical Block–cyclic Distributed Parallel LU Factorization Method (VBPLU) is effectively processed on a distributed memory parallel computer. VBPLU is based on the two techniques, the block algorithm and the aggregation of communications. Since startup time dominates the data communication and the aggregation reduces communication isssues, the total performance has been much improved. Furthermore this method uses long vectors so that it is also advantageous on vector processors. In this paper, we have constructed a modeling of VBPLU using a simplified LogGP model with analytical formulae, and estimated accurately the computational cost taking into account load distributions caused by data layout and process mapping. Some knowledge for optimization of block algorithm has been obtained. Our estimations have been verified through numerical experiments on three different distributed memory parallel computers. 相似文献
36.
37.
Toshiyuki Abe Junji KubotaTamotsu Tanaka Kuniaki ShojiAkio Tajiri Masao Kaneko 《Electrochimica acta》2002,47(24):3901-3907
Electrocatalytic O2 reduction was studied using a modified electrode coated with a Nafion membrane (Nf) dispersing a trinuclear ruthenium ammine complex ([(NH3)5RuIIIORuIV(NH3)4ORuIII(NH3)5]Cl6, Ru-red). When measuring cyclic voltammogram under O2 atmosphere (at 0.5 mV s−1), catalytic currents due to O2 reduction were found to develop below −0.2 V (vs. Ag/AgCl). Since Ru-red undergoes irreversible decomposition into the mononuclear complexes via the reduced state (RuIII-RuIII-RuIII) (∼−0.1 V), it is suggested that the electrocatalysis originates from the decomposed species (initial active species: RuII(NH3)5(OH2) and RuII(NH3)4(OH2)2) rather than from the Ru-red. Although the present electrocatalyst was also applied to H2O2 reduction system, the catalytic activity was found to be poor from the voltammetric behavior. It appeared that the kinetics of the electrocatalysis is much faster in the O2 reduction than in the H2O2 one. A selective and direct catalysis for O2 reduction into H2O was suggested from a ring-disk voltammogram to take place by an aggregate of the mononuclear ruthenium complexes in the polymer matrix. In addition, it was found that electrocatalytic O2 reduction involves a slow kinetic process, so that factors affecting the overall kinetics were discussed in terms of the catalysis mechanism. 相似文献
38.
Bubble wake visualization by using photochromic dye 总被引:1,自引:0,他引:1
Wake structure of a single “clean bubble”, rising in rectilinear, zigzagging or spiraling path, is experimentally investigated. A single nitrogen gas bubble was produced in a silicone oil pool and the wake structure development in the rear of the rising bubble was visualized by using photochromic dye. The flexibility of this visualization method enabled us to distinguish wake from drift easily. Both bubble motion and wake structure were recorded by using stereo high-speed video camera simultaneously. We present the first experimental support for the existence of the standing eddy at the rear of the clean bubble, as predicted by a previous numerical study by Ryskin and Leal [1984. Journal of Fluid Mechanics 148, 19-35], Dandy and Leal [1986. Physics of Fluids 29(5), 1360-1366] and Blanco and Magnaudet [1995. Physics of Fluids 7(6), 1265-1274]. We study motion of a pair of vortex filaments, which is called double-threaded type wake, in the case of bubble rising in an axi-asymmetric path. Visualization results of multiple formations of horse-shoe type vortices in one period of zigzag motion of rising bubble with shape oscillations, which has not been observed in previous studies are also presented. 相似文献
39.
Toshio Ogasawara Yuichi Ishida Takashi Ishikawa Takahira Aoki Toshiyuki Ogura 《Composites Part A》2006,37(12):2236-2240
Helium gas permeability of silicate clay (montmorillonite) particles/epoxy nanocomposites was examined. The incorporation of increasing amounts of montmorillonite particles reduced the helium gas permeability. Based on Fick’s law, gas permeation behavior of the nanocomposite was evaluated. With the increase of montmorillonite loading, gas diffusivity decreased, while gas solubility increased. Helium diffusion behavior is in agreement to the numerical results based on the Hatta–Taya–Eshelby theory. It has been revealed that dispersion of nanoscale platelets in polymer is effective in improving gas barrier property. 相似文献
40.
Keiko Ohtsuka Hajime Kimura Toshiyuki Iwai Akihiro Matsumoto 《Polymer International》2014,63(4):752-759
Sulfur‐containing allyl ester, which reacts with diallyl phthalate (DAP) resin to have allyl groups, was synthesized by the reaction of allyl phthalic acid with bisphenol having sulfur atoms. The sulfur‐containing allyl ester compound was blended with DAP resin to improve the adhesive properties to copper. By modification with sulfur‐containing allyl ester compound, the T‐peel adhesive strength and the lap shear adhesive strength to copper was improved. In particular, the adhesive strength was greatly improved when the resin was modified with the allyl ester compound having a disulfide bond (?S?S?) (DADS). It is concluded that this result is due to the improvement of the interfacial adhesive strength because the sulfur atom was found to be located in the surface of the copper by Fourier transform infrared (FTIR) analysis. The glass transition temperature (Tg) and the thermal decomposition temperature (Td) of the cured DAP resin modified with DADS slightly decreased with increasing concentration of DADS. The lowering of Tg is because the crosslinking density of the DAP resin modified with DADS is smaller than that of DAP resin. Moreover, from thermogravimetric analysis, the lowering of Td of the DAP resin modified with DADS is because DADS is likely to pyrolyze. © 2013 Society of Chemical Industry 相似文献