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41.
In this paper, two types of spiral groove bearing (SGB) spindles, a rotating‐shaft spindle and a fixed‐shaft spindle, are analysed, and the dynamic characteristics of these two types of spindles are tested and compared. The effects of lubricants on the dynamic characteristics and power consumption of the spindles are considered. It is found that the dynamic characteristics of the fixed‐shaft spindle are much better in terms of non‐repeatable run out than those of the rotating‐shaft spindle. The lubricants are found to have significant effects on both the dynamic characteristics and power consumption of the spindles. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
42.
Mikihiko Kobayashi Hiroshi Fudouzi Mitsuru Egashira Norio Shinya 《Materials & Design》2000,21(6):571-574
The method by which micrometer-sized particles are arranged, is described. An electrified pattern is drawn on a polished insulating substrate using a SEM with a CAD facility. The substrate is dipped in a suspension of particles. The particles adhere to the substrate and form the pattern corresponding to the electrified pattern by the electrostatic force. The arranged particles are fixed by coating with a fluoride polymer of thin film. The method is applicable to the production of an inflammable gas sensor. 相似文献
43.
The ion-selective property of hydrous ferric oxide precipitate films has been investigated by measuring membrane potentials which arise across precipitate membranes of hydrous ferric oxide with and without adsorbed MoO42? ions and of ferric molybdate in solutions of NaCl, KCl, MgCl2, CaCl2, BaCl2, AlCl3, and FeCl3. The hydrous ferric oxide membrane was only permeable to Cl? ions in chloride solutions, whereas the membrane with adsorbed MoO42? ions was permeable to cations in NaCl and KCl solutions, and to both Cl? and cations in the presence of multivalent cations. The ferric molybdate membrane was permeable to Cl? and cations in NaCl and KCl solutions, and only to Cl? ions in the presence of multivalent cations. It is suggested that in chloride solutions, the corrosion of iron covered with a precipitate film of hydrous ferric oxide is accelerated by enrichment of Cl? ions under the film, which may decrease the local pH and introduce a positive diffusion potential in the film. The adsorption of MoO42? ions on the oxide changes the ion-selectivity of the precipitate film from the anion-selective to the cation-selective in solutions of NaCl and KCl. This cation-selectivity of the film may inhibit the corrosion of iron, because of H+ ions diffusing out of the film. The inhibitive effect of MoO42? ions would be reduced in the presence of multivalent cations. 相似文献
44.
The carbon black/alumina gel composites were prepared by sol-gel reaction of aluminum isopropoxide in the presence of polymer-grafted carbon black. The electric resistance of the alumina gel composite from polymer-grafted carbon black was very sensitive to vapor of good solvent for grafted polymer on carbon black: the electric resistance of the alumina gel composite suddenly decreased in solvent vapor and returned to initial resistance when it was transferred into dry air. The effect of surface area and particle size of carbon black on the responsiveness was also investigated. In addition, the electric resistance of the alumina gel composite was found to respond to water and methanol in n-hexane and diethyl ether. 相似文献
45.
The Green's functions of a point dislocation, a concentrated moment, a normal point force, a couple moment, and a couple bending force applied to an infinite plate with an arbitrarily shaped hole under a displacement boundary condition are derived in this paper. The closed-form stress functions are obtained by using the technique of the rational mapping function and the complex stress function approach. In the derivation, the analytical continuation and Cauchy integral are used for the different actions. Without loss of generality, some calculated results are shown for a square hole under a fixed boundary. The solutions show that the stress functions have different orders of singularity for the different actions. In order to illustrate the stress level due to bending moment and shear force clearly and efficiently, the effective stress of thin plate bending is shown. 相似文献
46.
47.
Abstract— Of the two types of thermal‐stress processes for glass, i.e., surface scribing and full body cleavage, the latter is not presently applied in commercial manufacturing due to the technical difficulties, notwithstanding its various advantages. These difficulties, which were pointed out by Kondratenko and were refered to as size effect, consist of a reduced processing speed in a large glass plate and the positional inaccuracy when cleaving close to edges of a glass plate. The result of the investigation aimed to solve these problems, which can pave the way to the commercial application of full body cleavage in the manufacturing of flat‐panel‐display (FPD) devices, is reported. 相似文献
48.
In this study, the Green's function of a point dislocation for the mixed boundary value problem of a thin plate is derived and then employed to analyze the interaction problem between a partially bonded rigid inclusion and a line crack in an infinite plate under uniform bending moments at infinity. A rational mapping technique and the complex stress function approach are used in the derivation. Based on the method of analytical continuation, the problem of obtaining the stress functions is reduced to a Riemann-Hilbert problem. Without loss of generality, the numerical results are demonstrated for a square rigid inclusion with a debonding. The stress intensity factors of crack tips and the stress intensities of debonding tips are shown for various parameters. 相似文献
49.
50.
Norio Tokuda Hitoshi Umezawa Sung-Gi Ri Masahiko Ogura Kikuo Yamabe Hideyo Okushi Satoshi Yamasaki 《Diamond and Related Materials》2008,17(7-10):1051-1054
A process of homoepitaxial growth of diamond (111) films by microwave plasma-enhanced chemical vapor deposition has been investigated characterizing areas by ex-situ atomic force microscopy. The evolution of surface morphology during a lateral growth of (111) diamond was visualized utilizing a mesa structure as a marker. Lateral growth forms atomically flat surfaces, which show atomically flat terraces over several hundred nm widths and single bilayer steps of (111) diamond. 相似文献