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151.
In Japan, the lubricating oil used for the internal combustion engine of passenger cars is usually exchanged for fresh oil after running a distance in the range from 3,000 to 10,000 km. Refining of the used engine oil is very costly because friction-reducing additives containing sulfur, phosphorus, etc., are included in the oil. Therefore, wasted engine oil (used engine oil) is burned in many cases. This investigation was conducted to effectively re-use wasted engine oil without chemical refining. Performance of used engine oil as a gear-cutting oil was examined by conducting five kinds of experiments: (a) chemical analyses of the oils, (b) measurements of friction coefficients on the four-ball tester, (c) tool wear tests using a lathe, (d) tool life tests using a gear-cutting machine, and (e) accuracy and surface finish of the cut gears. In contrast to general expectations, longer tool lives were obtained when the used engine oils were used instead of a high-grade gear-cutting oil. The reason for this was discussed and it was concluded that used engine oil may be used as a high-performance gear-cutting oil if health risks for workers are removed. 相似文献
152.
The existence states of deuterium in LiAlO2 were analyzed by in situ IR absorption spectroscopy during irradiation with 3 keV at room temperature. Multiple IR absorption peaks that were related to O-D stretching vibrations were observed, mainly at 2650 cm−1 (O-Dα), 2600 cm−1 (O-Dβ), and 2500 cm−1 (O-Dγ). The O-Dα was assigned to the surface O-D. The O-Dβ and O-Dγ were interpreted as two distinct O-D states for three candidates: O-D of substitutional D+ for Li+; O-D of substitutional D+ for Al3+; and O-D of interstitial D+. O-Dβ was the dominant O-D state for deuterium irradiated into LiAlO2, and had higher stability than O-Dγ. Heating after ion irradiation led to the desorption of D2 and an increase in the intensity of O-Dβ, which implies that some of the deuterium irradiated into LiAlO2 exists in non-O-D states, such as D− captured by F centers. 相似文献
153.
This paper presents the influence of latent heat load by changing the relative humidity of air flow distribution in the super‐heated gas region in an evaporator and the effect of the refrigerant flow path pattern. To estimate the influence, we applied the thermal network method that can consider refrigerant quality distribution in the heat exchanger. If the super‐heated gas region spreads to the upper wind row, humid air goes through the heat exchanger without drying, called “air flow bypass.” To suppress this phenomenon and simultaneously obtain the best performance, we chose an optimum path pattern on the basis of this method. As a result, the prediction shows that performance of the evaporator is recovered 5% for a simple 2‐row 2‐path heat exchanger when 40% of the unbalance of air flow rate occurs. © 2010 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20302 相似文献
154.
Lixin Xiao Masaki Ozawa Mituhiro Iwaya Jian Wang Hidekazu Shimotani Nita Dragoe Satoru Tanibayashi Koichi Kitazawa 《Fullerenes, Nanotubes and Carbon Nanostructures》2000,8(1):77-88
A series of regioisomeric bis-methanofullerenes (diethyl [60]fullerenobisacetate) were prepared by reaction of the sulfonium ylide with C60. Seven stable resultant regioisomers were completely isolated on a preparative HPLC and identified by FT-IR, UV-vis, TOF-MS, and 1H and 13C NMR measurements. The structures of these bisadducts were assigned based on 1) the relationship of the polarities of the regioisomers with the elution order from HPLC; 2) a comparison of their UV-vis spectra with those of corresponding Bingel-Hirsch bisadducts; and 3) the identification of their molecular symmetries by their 1H and 13C NMR spectra. The electrochemical properties of the resultant regioisomeric bismethanofullerene, derivatives were investigated through cyclic voltammetry (CV). The bisadducts exhibited more negative reduction potential than the pristine C60. Trans-2- and cis-3- bisadducts had the least negative potential E11/2 of all the other bisadducts. 相似文献
155.
Sn-Zn alloy thin films were deposited on a polyester (PET) film substrate by co-evaporation and evaluated their surface, tensile and adhesion properties with a vacuum forming test and pull test.Relationship between the surface roughness and elemental composition of these thin films was evaluated. The surface roughness decreased with increase of the Sn content.The tensile property was estimated by observations of micro-cracks of the thin films due to a vacuum forming test. Sn-Zn alloy thin film, whose elemental composition is 85:15 (wt%), had high vacuum forming durability.The adhesion strength between the Sn-Zn alloy thin films and PET substrate was measured with a pull test apparatus. The pull strength decreased with increase of the Sn content. 相似文献
156.
Katsuyuki Umezawa Seiichi Susaki Satoru Tezuka Shigeichi Hirasawa 《IEEJ Transactions on Electrical and Electronic Engineering》2007,2(1):84-93
We have developed a public key certificate validation system considering the restrictions peculiar to the mobile environment, such as processing the speed and memory capacity of a cellular‐phone terminal, and the network transmission speed. In this paper we derive a theoretical formula showing the performance of a validity check of the public key certificate of the conventional system and of the proposed system, and compare and examine a theoretical value in a mobile environment. Moreover, we evaluate the actual measurement that uses the server and cellular‐phone terminal that we developed. We show that our proposed system based on the certificate validation server (CVS) system is better than the conventional system from the viewpoint of processing speed and transmission speed. Copyright © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
157.
Effects of ultrasonic irradiation on crystallization behavior of tripalmitoylglycerol and cocoa butter 总被引:2,自引:2,他引:0
Kaoru Higaki Satoru Ueno Tetsuo Koyano Kiyotaka Sato 《Journal of the American Oil Chemists' Society》2001,78(5):513-518
Effects of application of ultrasonic power (20 kHz, 100 W) on the crystallization behavior of tripalmitoylglycerol (PPP) and
cocoa butter have been examined in terms of rate of nucleation and polymorphic control. High-purity PPP (>99%) and low-purity
PPP (>80%) samples were employed to mimic real fat systems, which usually have higher concentrations of minor components in
addition to the main component. For both the high-purity and low-purity PPP, the application of ultrasonic power accelerated
the rate of nucleation as measured by induction time for the occurrence of crystals and by the number of crystals nucleated.
As for the polymorphic influences, the nucleation of both the β′ and β forms was accelerated by the ultrasound, yet the β′
form nucleation was more accelerated when the low-purity PPP samples were employed. As for cocoa butter, sonication for a
short period accelerated the crystallization of Form V. The present results indicate that ultrasound irradiation is an efficient
tool for controlling polymorphic crystallization of fats. 相似文献
158.
Polyvinyl chloride (PVC) is the most popular insulating material for electric wiring instruments. However, an exothermic reaction above 150 °C may cause deterioration of the insulating properties of PVC. Therefore, it is important to clarify the heat degradation in PVC, not only to investigate the ignition of electrical wiring products but also to use electrical products safely. It is known that ultraviolet (UV) irradiation causes chemical deterioration of PVC and an increase in its conductivity. Generally, it has been thought that the electrical breakdown properties, electrical conduction, and insulating performance are affected by space charge accumulation in an insulating material. A high temperature pulsed electroacoustic (PEA) system usable up to 250 °C has been developed, and the PEA system can measure the space charge distribution and conduction current in the high temperature range simultaneously. In this investigation, the space charge distribution and conduction current were measured up to electrical breakdown in a non‐UV irradiated sample (normal PVC) and in 353 nm and 253 nm UV‐irradiated PVC samples in the range from room temperature to 200 °C in a DC electric field. In the short wavelength UV irradiated PVC sample (253 nm, 300 h), a deterioration of breakdown strength at 90 °C to 150 °C and negative packet‐like charges were observed at 60 °C and 100 °C, a positive charge accumulated in front of both the anode and cathode above 90 °C, and a higher electric field near the cathode side because the positive charge of the cathode side was greater. 相似文献
159.
To achieve smooth real-world interaction between people and computers, we developed a system that displays a three-dimensional
computer-graphic human-like image from the waist up (anthropomorphic software robot: hereinafter “robot”) on the display,
that interactively sees and hears, and that has fine and detailed control functions such as facial expressions, line of sight,
and pointing at targets with its finger. The robot visually searches and identifies persons and objects in real space that
it has learned in advance (registered space, which was our office in this case), manages the history information of the places
and times it found objects and/or persons, and tells the user, indicating their three-dimensional positions with line of sight
and its finger. It interactively learns new objects and persons with line of with their names and owners. By using this function,
the robot can engage in simple dialogue (do a task) with the user.
Osamu Hasegawa, Ph.D.: He received the B.E. and M.E. degrees from the Science University of Tokyo, in 1988, 1990 respectively. He received Ph.D.
degree from the University of Tokyo, in 1993. Currently, he is a senior research scientist at the Electrotechnical Laboratory
(ETL), Tsukuba, Japan. His research interests include Computer Vision and Multi-modal Human Interface. Dr. Hasegawa is a member
of the AAAI, the Institute of Electronics, Information and Communication Engineers, Japan (IEICE), Information Processing
Society of Japan and others.
Katsuhiko Sakaue, Ph.D.: He received the B.E., M.E., and Ph.D. degrees all in electronic engineering from the University of Tokyo, in 1976, 1978
and 1981, respectively. In 1981, he joined the Electrotechnical Laboratory, Ministry of International Trade and Industry,
and engaged in researches in image processing and computer vision. He received the Encouragement Prize in 1979 from IEICE,
and the Paper Award in 1985 from Information Processing Society of Japan. He is a member of IEICE, IEEE, IPSJ, ITE.
Satoru Hayamizu, Ph.D.: He is a leader of Interactive Intermodal Integration Lab. at Electrotechnical Laboratory. He received the B.E., M.E., Ph.D.
degrees from Tokyo University. Since 1981, he has been working on speech recognition, spoken dialogue, and communication with
artifacts. From 1989 to 1990, he was a visiting scholar in Carnegie Mellon University and in 1994 a visiting scientist in
LIMSI/CNRS. 相似文献
160.
Katsumi Katoh Satoru Yoshino Shiro Kubota Yuji Wada Yuji Ogata Masaru Nakahama Shuhei Kawaguchi Mitsuru Arai 《Propellants, Explosives, Pyrotechnics》2007,32(4):314-321
The thermal behavior of nitrocellulose (NC) containing diphenylamine (DPA), 2‐nitrodiphenylamine (2‐NO2‐DPA), N‐nitrosodiphenylamine (N‐NO‐DPA), ethyl centralite (EC), akardite II (AKII), 1,1,3‐tri‐(2‐methyl‐4‐hydroxy‐5‐tert‐butyl‐phenyl)‐butane (BPless), 3‐(3,5‐di‐tert‐butyl‐4‐hydroxy‐phenyl)‐propionic acid octadecyl ester (BPhin), and 3‐(3‐tert‐butyl‐4‐hydroxy‐5‐methyl‐phenyl)‐propionic acid 2‐(9‐{2‐[3‐(3‐tert‐butyl‐4‐hydroxy‐5‐methyl‐phenyl)‐propionyloxy]‐1,1‐dimethyl‐ethyl}‐2,4,8,10‐tetraoxa‐spiro [5.5] undec‐3‐yl)‐2‐methyl‐propyl ester (BPsemi) was observed during isothermal storage at 393 K using a C80 microcalorimeter. The results indicate that each stabilizer decreased NC's maximum heat release rate and increased the induction period of heat release. We also observed that the maximum heat release rate and the induction period were dependent on the amount of stabilizer. DPA decreased the maximum heat release rate to the greatest extent, with the other stabilizers having similar effects on the decrease of maximum heat release rate. AKII prolonged the induction period of heat release most. The order of prolongation of the induction period was AKII>2‐NO2‐DPA≈DPA>N‐NO‐DPA≈EC>BPless≈BPsemi≈BPhin. 相似文献