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991.
The squeeze film formation ability of traction fluids is studied under impact load by dropping a steel ball‐bearing against a flat anvil made of mild steel. The effect of the pressure–viscosity coefficient and of the viscosity is investigated for plastic impact. The depth difference between the lubricated surface dent and the dry dent increases linearly with the product αη of the pressure–viscosity coefficient α and the viscosity η. The importance of the lubricant parameter αη is observed under the squeeze film formation ability from contact voltage or elastohydrodynamic lubrication central film thickness measurement at rolling condition. The intensity of each impact collision is measured by means of an acoustic emission (AE) sensor. The high‐pressure short‐time solidification of traction fluids was confirmed by dent analysis after the impact tests and AE analysis under impact loads. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
992.
ZHAO Dong-Yu IMAIZUMI Hiroshi LEI Qing-Quan ZHAO Dong-Mei 《核技术(英文版)》2005,16(6):352-357
In order to reveal the reactivity of a functional group in an aromatic compound having two substituents in the aromatic ring, the hydrogen-isotope exchange reaction (T-H exchange reaction) between tritiated water vapor (HTO vapor) and 4-amino-2-methylbenzenesulfonic acid (and 5-amino-2-methylphenol) were dynamically observed at 50℃ (and 70℃) in a gas-solid system. Consequently, the fact that the specific activity of the acid increased with time was obtained, and the T-for-H exchange reaction occurred. By applying the A"-McKay plot method to the data observed, the rate constant of each functional group for the reaction was obtained. After the additive property of the Hammett's rule was applied to this work, the new substituent constants were obtained. From the above-mentioned, the following four items have been confirmed: (1) the reactivity of the functional groups can be dynamically analyzed, and the A"-McKay plot method is useful to analyze the reactivity; (2) the additive property of the Hammett's rule is applicable to quantitative comparison of the reactivity of the functional groups; (3) the reactivity of the functional groups can be simultaneously analyzed by using the A "-McKay plot method in the T-H exchange reaction; and (4) the method used in this work is also useful for analyzing the reactivity of a certain material having some kinds of func- tional groups. 相似文献
993.
Toshifumi Yuji Kazunari Fujioka Shuitsu Fujii Hiroshi Akatsuka 《IEEJ Transactions on Electrical and Electronic Engineering》2007,2(4):473-475
To understand the mechanism of surface processing by atmospheric pressure nonequilibrium microwave discharge plasma jets of coaxial type without a resonator, we measured the vibrational and rotational temperatures in plasmas using optical emission spectroscopy. The plasma was excited by a microwave power supply, using a gas mixture of Ar and N2 as the plasma gas, and changing the flow rate of N2 gas. We also measured the change in the contact angle of a PET film before and after the plasma processing. It decreased as the plasma rotational temperature increased, indicating that the hydrophilicity of the PET surface was improved as the plasma rotational temperature became higher. © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
994.
Atsushi Teramoto Takayuki Murakoshi Masatoshi Tsuzaka Hiroshi Fujita 《IEEJ Transactions on Electrical and Electronic Engineering》2007,2(2):195-197
Chip components mounted on the printed circuit board are rapidly being miniaturized. Furthermore, the fillet‐less chip soldering technique, which does not use a solder fillet, is widely used in portable products such as mobile phones. However, there is no method to inspect the soldering of fillet‐less chip mounting. In this paper, we propose an automated X‐ray inspection technique for fillet‐less chip mounting. It extracts three inspection parameters from the X‐ray image. In the experiments, we evaluate the repeatability and inspecting ability of the technique and confirm that sufficient information for failure detection is obtained. An automated X‐ray inspection system using this technique is now in operation at some factories, so in conclusion our automated method would be useful in practice. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
995.
996.
Isao Kobayashi Mitsutoshi Nakajima Hiroshi Nabetani Yuji Kikuchi Atsushi Shohno Kazumi Satoh 《Journal of the American Oil Chemists' Society》2001,78(8):797-802
Micron-scale monodisperse oil-in-water (O/W) micropheres (MS) were prepared using a novel microchannel (MC) emulsification
technique. The characteristics of the MS preparation and the O/W-MS prepared were studied. Soybean oil and medium-chain triacyglycerol
(MCT) were used as the disprrsed phase, and physiological saline was used as the continuous phase. Silicon MC with 1 to 3μm-equivalent
channel diameters were employed. A novel MC module was devised to easily recover the O/W-MS prepared. The effects of the channel
shape on the behavior of MS formation, on the MS size, and on the distribution were investigated. An MC with a terrace at
the MC outlet stably yielded micron-scale monodisperse O/W-MS; the MS had diameters of about 5 μm, and their coefficients
of variation were below 9%. Monodisperse food-grade O/W-MS with diameters of about 4 μm could be obtained by using polyglycerol
fatty acid ester as the surfactant. The size and size distribution of the recovered O/W-MS remained almost constant over 60
d, demonstrating their long-term stability. 相似文献
997.
The effect of the geometrical and operational parameters on the mixing characteristics of a Couette–Taylor vortex flow reactor (CTVFR) were investigated and were correlated with the same parameters by using the tank‐in‐series model. Continuous emulsion polymerization of styrene was conducted at 50°C in a CTVFR to clarify the effects on kinetic behavior and reactor performance of operational parameters such as rotational speed of inner cylinder (Taylor number), reactor mean residence time, and emulsifier and initiator concentrations in the feed streams. It was found that steady‐state monomer conversion and particle number could be freely varied only by varying the Taylor number. In order to explain the observed kinetic behavior of this polymerization system, a mathematical model was developed by combining the empirical correlation of the mixing characteristics of a CTVFR and a previously proposed kinetic model for the continuous emulsion polymerization of styrene in continuous stirred tank reactors connected in series (CSTRs). On the basis of these experimental results, it was concluded that a CTVFR is suitable for the first reactor (prereactor) of a continuous emulsion polymerization reactor system. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1931–1942, 2001 相似文献
998.
In the weak magnetic field perpendicular to the discharge electric field, both the electrons and positive ions are transported in the direction of E×B drift by the space charge electric field produced by the preceded electrons. As a result, radicals are generated uniformly outside of discharge space between the electrodes in the direction of E×B drift. On the other hand, negatively charged heavy particles such as dust particles can be removed from discharge space in the direction opposite to E×B drift of plasmas. The authors have studied the transport mechanisms of magnetized dusty plasmas and its applications for the large-area uniform a-Si:H thin film deposition in plasma CVD methods. This paper reviews the transport phenomena and the transport mechanisms of dust particles and the results of film preparation under particle-free process conditions. 相似文献
999.
The sulfidation properties of Ni–20Cr and Ni–13.5Co–20Cralloys as well as a nickel-base superalloy AISI685 were investigated at873 K in H2S–H2 gas mixtures with sulfur partial pressures of10–4, 10–5.5, and 10–7Pa by mass-gain measurements,electron-probe microanalysis (EPMA), and X-ray diffraction (XRD)analysis. Sulfidation obeyed the parabolic rate law, and the parabolic rateconstants decreased in the order Ni–20Cr, Ni–13.5Co–20Cr,and AISI685 at each sulfur pressure. With decreasing sulfur pressure, therate constants first decreased slowly and then rapidly at a 10–7 Pasulfur pressure. At both 10–4 and 10–5.5 Pa sulfur pressures,Ni–20Cr formed a surface scale with a duplex structure of inner(Cr3S4) and outer (Ni3S2) layers, while Ni–13.5Co–20Cr formeda triplex structure of inner (Cr3S4), intermediate(Ni,Co)Cr2S4, and outer[Ni3S2+(Co,Ni)9S8] layers. Thesurface scale formed on AISI685 was verycomplex, comprising at least four layers, a fibrous (Co,Ni)9S8 top surface,outer [Ni3S2+(Co,Ni)9S8], and intermediate [(Cr,Ti)3S4] layers, as well asan inner layer containing Cr, Ti, Mo, Al, and S. At the 10–7 Pa sulfurpressure, which is lower than the dissociation pressure of Ni3S2, bothNi–20Cr and Ni–13.5Co–20Cr formed a surface scale ofCr3S4 covered by a thin NiCr2S4 layer, accompanied by copious internalsulfidation of Cr3S4 and/or CrS. On AISI685 there was a surface scale of(Cr,Ti)3S4 accompanied by the usual internal sulfidation. It is discussedthat diffusion of cations in the inner Cr3S4 layer is the rate-determiningstep for the growth of the multilayer structures. At the 10–7 Pasulfur pressure, diffusion of Cr and S contribute to form a thin surfacescale and internal sulfidation, respectively. 相似文献
1000.
聚氨酯弹性体电致伸缩性能研究 总被引:1,自引:0,他引:1
以聚(己二酸-丁二醇-新戊二醇)酯二元醇、甲苯二异氰酸酯、1,4-丁二醇和三羟甲基丙烷为原料,经聚合得到了一系列聚氨酯弹性体。利用LCR阻抗分析仪研究了所得聚氨酯弹性体的介电性能。在1kHz频率下聚氨酯弹性体的相对介电常数为7左右,相对介电常数随测试频率的增加而降低。采用数字散斑相关测量方法研究了聚氨酯弹性体在电场诱导下的应变─电致伸缩响应之间的关系。结果表明,聚氨酯弹性体在外加高压电场的作用下,随着高压电源的开合,其应变也随之呈现出相应的收缩与回复,其电致伸缩系数随聚氨酯弹性体密度的增加及相对介电常数的减小而降低。 相似文献