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41.
Al etching was studied employing negative ions generated in downstream Cl2 plasma. The Al etch rate by the alternate irradiation of positive and negative ions was two times higher than that by usual
positive ions. In order to etch the Al film practically on an insulator covered electrode coupled with RF power, reduction
of the negative self bias voltage (Vdc) was examined using a magnetic filter which traps electrons. The reason for the high
etching reactivity is that the dominant negative ions F in SF6 and Cl− in Cl2 plasmas are atomically very similar to the radicals. Addition of SF6 and H2 to a Cl2/BCl3 mixture reduced Vdc significantly. However, fluorine and hydrogen atoms inhibited Al etching in spite of sufficient ion energy. 相似文献
42.
Atmospheric corrosion of steel proceeds under thin electrolyte film formed by rain and dew condensation followed by wet and dry cycles. It is said that rust layer formed on steel as a result of atmospheric corrosion strongly affects the corrosion behavior of steel. The effect of environmental corrosiveness on the formation process and structure of the rust layer is, however, not clear to date. In this study, in situ observation of the rusting process of a carbon steel covered with a thin film of Na2SO4 or NaCl solution was performed under a wet/dry repeating condition by X-ray diffraction spectroscopy with white X-rays obtained from synchrotron radiation. The present in situ experiments successfully detected initial process of the rust formation. In the early cycles, the rust constituents were not well crystallized yet, but the presence of Fe(OH)2 and Fe(OH)3 was confirmed. In the subsequent cycles, two different solutions resulted in difference in preferential phase of the rust constituents. α-FeOOH was preferentially formed in the case of the Na2SO4 solution film, whereas β-FeOOH appeared only under the NaCl solution film. 相似文献
43.
Masamitsu Watanabe Etsuko Toyoda Toshihiro Ichino Yasuhiro Higashi 《Corrosion Science》2007,49(2):766-780
Copper plates were exposed under sheltered outdoor conditions for up to one year, starting in September 2001 in Musashino City, Tokyo, a suburban area. Following various periods of exposure, the patinas on the plates were characterized to investigate their evolution by using X-ray fluorescence analysis, X-ray diffraction, field emission scanning electron microscopy, and glow discharge optical emission spectroscopy. The difference in the roles of sulfur and chlorine in the early stages of copper patination were identified by analyzing the depth profiles of these two elements. Sulfur was found on top of the patina as cupric sulfates such as posnjakite (Cu4SO4(OH)6 · H2O) or brochantite (Cu4SO4(OH)6). Brochantite appeared only after 12 months of exposure. In contrast, chlorine was found on the surface after only one month of exposure. It gradually penetrated the patina as the exposure period lengthened, forming copper chloride complexes. Chloride ions accumulated at the patina/copper interface, forming nantokite (CuCl), which promoted corrosion. 相似文献
44.
We analyzed the copper corrosion products that formed during a month in summer and a month in winter at three sites in Tokyo using several analytical techniques. The X-ray diffraction patterns revealed that cuprite Cu2O and posnjakite Cu4SO4(OH)6·H2O formed on copper exposed in summer. By contrast, only cuprite was found in winter exposed copper. The X-ray fluorescence results indicated that the amounts of sulfur and chlorine on the copper plates exposed in summer were much greater than those in winter. This could be explained by the change in particulate sulfate and sea salt concentrations. Depth profiling analysis by Auger electron spectroscopy revealed that the oxide layer formed in summer was thicker than that in winter. This difference in oxide layer thickness could have been due to the differences in temperature, relative humidity, and the amount of sulfur and chlorine on the copper plate. 相似文献
45.
Kazunori Sakata Kosuke Nakano Hirofumi Miyahara Yasuhiro Matsubara Keisaku Ogi 《Journal of Thermal Spray Technology》2007,16(5-6):991-997
This article describes microstructure control aimed for wear-resistance improvement of Co-based (Co-Cr-W-B-Si) self-fluxing
alloy coating by diffusion treatment. The diffusion treatments of thermally sprayed Co-based self-fluxing alloy coating on
steel substrate were carried out at 1370-1450 K for 600-6000 s under an Ar gas atmosphere. Microstructural variations of the
coating and the interface between the substrate and the coating were investigated in detail. A proper diffusion treatment
precipitates two kinds of fine compounds in Co-based matrix. X-ray diffractometer (XRD) and electron probe microanalyzer (EPMA)
analysis revealed these precipitates to be a chromium boride dissolving cobalt and a tungsten boride containing cobalt and
chromium. The size of each precipitate became larger with increasing treatment temperature and time. A coating with the proper
size borides showed a superior wear-resistance.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
46.
Ryu Komatsu Ryo Nakazato Takeru Sasaki Akio Suzuki Naoyuki Senda Takuya Kawata Yasuhiro Jimbo Tomoya Aoyama Naoto Ohno Susumu Kawashima Hisao Ikeda Shingo Eguchi Yoshiharu Hirakata Shunpei Yamazaki Takashi Shiraishi Seiji Yasumoto Masataka Nakada Masataka Sato Chris Bower Darryl Cotton Andrew Matthews Piers Andrew Catalin Gheorghiu Johan Bergquist 《Journal of the Society for Information Display》2015,23(2):41-49
In this study, a 5.9‐inch foldable active‐matrix organic light emitting diode (AMOLED) display was developed. A folding test was performed repeatedly. The display survived the folding test (100,000 folds) with a curvature radius of 2 mm. To protect an organic light emitting diode (OLED) against moisture, inorganic passivation layers are provided on the upper and lower sides of the flexible display. Using our transfer technology, high density passivation layers can be obtained. The measured water vapor transmission rate of the layer is 7 × 10?6 g/m2?day or less, which improves OLED reliability. With these techniques, we have developed a book‐type display, which is repeatedly foldable like a book, and a tri‐fold display including a display area, which is foldable in three. 相似文献
47.
Yasuhiro Jimbo Yuki Tamatsukuri Minato Ito Kohei Yokoyama Yoshiharu Hirakata Shunpei Yamazaki 《Journal of the Society for Information Display》2015,23(7):313-318
To improve the reliability and mechanical durability of a flexible organic light‐emitting diode display, the entire flexible display is coated with an aluminum oxide film by atomic layer deposition (ALD). Because the step coverage of ALD is excellent, the AlOx film was deposited not only on the front and back surfaces but also on the side surfaces of the display. A high‐temperature and high‐humidity preservation test, repetitive bending tests, and a pencil hardness test were conducted on the flexible display with ALD‐AlOx coating. The display survived 500 h of a 65°C, 95% preservation test, endured a 100,000‐time repetitive bending test with a curvature radius of 4 mm, and was found to have a pencil hardness of 4H. 相似文献
48.
Yasuhiro MATSUDA Tsuneshi ISOMURA 《通讯和计算机》2009,6(2):55-64
Finger Braille is one of tactual communication media of deaf-blind people. Deaf-blind people who are skilled in Finger Braille can catch up with speech conversation, because of prosody of Finger Braille. Features of prosody are: (1) characters at the end of clauses are dotted long; (2) characters of voiced sounds and double consonants are dotted shortly. In this paper, we designed three teaching patterns which taught prosody of Finger Braille (dot conditions about duration of dotting). Teaching pattern 1 indicated a dot pattern with colored solid background. Teaching pattern 2 indicated a dot pattern with colored empty background. Teaching pattern 3 indicated a dot pattern with colored arrow (long or short). Every teaching pattern includes 6 colors (red, orange, yellow, green, blue and purple). In the questionnaire, the yellow pattern of teaching pattern 3 was selected as the most visible pattern. In the evaluation experiment, the yellow pattern of teaching pattern 3, the red and purple patterns of teaching pattern 1 (the least visible pattern) and the existing patterns without teaching of dot conditions are compared. As a result, every subject could dot long at the end of clauses and could dot shortly at the voiced sounds and double consonants. The answers of questionnaire indicated that the yellow pattern of teaching pattern 3 was also the most visible and easiest teaching pattern. 相似文献
49.
Masatsune Kato Takaaki Aoki Takashi Noji Yasuhiro Ono Yoji Koike Tomoyuki Hikita Yoshitami Saito 《Journal of Superconductivity》1994,7(1):37-38
We have investigated the relation between the crystal structure and superconductivity in La1.9Bi0.1CuO4+
, in which the phase separation observed in La2CuO4+
is suppressed. A phase diagram in theT– plane is given for La1.9Bi0.1CuO4+
with excess oxygen. For very small values, the crystal structure is orthorhombic, and an orthorhombic-tetragonal phase transition occurs markedly at 0.03 in the measured temperature range between 13 and 293 K. Superconductivity is observed in the range of 0.04<<0.11. This is clear evidence thathigh-T
c
superconductivity also appears in the tetragonal phase. 相似文献
50.
The present study investigated a numerical simulation of molding-defect formation during resin transfer molding using boundary element method and line dynamics. The proposed method enables to simulate small molding defects by increasing the node for required position during time evolution; thereby, the method computes high-resolution flow front without being affected by the initial mesh geometry. The method was applied to the radial injection RTM with single inlet, and it was confirmed by comparison with theoretical value based on Darcy’s law that the flow advancement was computed with high accuracy. In addition, the method was also applied to the flow advancement for inclusion problem with cylinder, and four-point injection problem. The simulated flow behavior, void formation, and shrinkage agreed with the results in references. Finally, the method was compared with experiments using two-point injection problem. The computed configuration of the flow front and weld line agreed well with the experimental results. 相似文献