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951.
Seol HJ Shiraishi T Tanaka Y Miura E Hisatsune K 《Journal of materials science. Materials in medicine》2002,13(2):237-241
The effect of Zn addition to AuCu on the age-hardening rate at the intraoral temperature was investigated to find out the proper condition for high age-hardening rate. The increase in hardness of Zn-added alloys during aging at 37 °C was due to the atomic ordering. With an increase in Zn concentration, hardness of a sample under the as-quenched condition decreased, but the age-hardening rate obviously increased. When Zn content was fixed, a higher solution treatment temperature was more effective for the age-hardening at 37 °C. It was suggested that the formation energy of a vacancy considerably decreased with an increase in Zn content. It is reasonable to consider that the amount of quenched-in excess vacancies are markedly increased with an increase in Zn content when the solution treatment temperature was fixed. By transmission electron microscopic observations, it was revealed that the formation of the AuCu II superstructure contributed to the age-hardening at 37 °C in the high zinc content alloy. 相似文献
952.
We demonstrate full-color imaging through a turbid medium by use of photorefractive coherence gating and a technique to separate the recording space of each color from those of the other colors. We found that the recording spaces must be separate when a multicolor image is recorded in a photorefractive crystal to prevent the interference of the holograms with one another. For full-color imaging we used a He-Cd white-light laser, which is compact and useful for full-color holography. Full-color-image retrieval is demonstrated through five mean free paths of a turbid medium. 相似文献
953.
Masatoshi Okutomi Yasuhiro Katayama Setsuko Oka 《International Journal of Computer Vision》2002,47(1-3):261-273
For recovering precise object boundaries in area-based stereo matching, there are two problems. One is the so-called occlusion problem. This can be avoided if we can select only visible cameras among many cameras used. Another one is the problem called boundary overreach, i.e. the recovered object boundary turns out to be wrongly located away from the real one due to the window's coverage beyond a boundary. This is especially harmful to segmenting objects using depth information. A few approaches have been proposed to solve this problem. However, these techniques tend to degrade on smooth surfaces. That is, there seems to be a trade-off problem between recovering precise object edges and obtaining smooth surfaces.In this paper, we propose a new simple method to solve these problems. Using multiple stereo pairs and multiple windowing, our method detects the region where the boundary overreach is likely to occur (let us call it BO region) and adopts appropriate methods for the BO and non-BO regions. Although the proposed method is quite simple, the experimental results have shown that it is very effective at recovering both sharp object edges at their correct locations and smooth object surfaces. We also present a sound analysis of the boundary overreach which has not been clearly explained in the past. 相似文献
954.
We have implemented Kima, an automated error correction system for concurrent logic programs. Kima corrects near-misses such as wrong variable occurrences in the absence of explicit declarations of program properties.Strong moding/typing and constraint-based analysis are turning out to play fundamental roles in debugging concurrent logic programs as well as in establishing the consistency of communication protocols and data types. Mode/type analysis of Moded Flat GHC is a constraint satisfaction problem with many simple mode/type constraints, and can be solved efficiently. We proposed a simple and efficient technique which, given a non-well-moded/typed program, diagnoses the reasons of inconsistency by finding minimal inconsistent subsets of mode/type constraints. Since each constraint keeps track of the symbol occurrence in the program, a minimal subset also tells possible sources of program errors.Kima realizes automated correction by replacing symbol occurrences around the possible sources and recalculating modes and types of the rewritten programs systematically. As long as bugs are near-misses, Kima proposes a rather small number of alternatives that include an intended program. Search space is kept small because the minimal subset confines possible sources of errors in advance. This paper presents the basic algorithm and various optimization techniques implemented in Kima, and then discusses its effectiveness based on quantitative experiments. 相似文献
955.
Oda Y Owa T Sato T Boucher B Daniels S Yamanaka H Shinohara Y Yokoi A Kuromitsu J Nagasu T 《Analytical chemistry》2003,75(9):2159-2165
956.
Yasuhiro Awakura Tetsuji Hirato Akihiko Kagawa Yoshiyasu Yamada Hiroshi Majima 《Metallurgical and Materials Transactions B》1991,22(5):569-574
The kinetics of malachite dissolution in aqueous ethylenediaminetetraacetate (EDTA) solution has been investigated in the
temperature range of 298 to 318 K. The dissolution rate of malachite determined under the present set of experimental conditions
was found to be independent of agitation speed. The dissolution rate increased with increasing EDTA concentration, but leveled
off at higher concentrations. At constant EDTA concentration, an increase in dissolution rate was detected at higher temperatures.
A dissolution mechanism involving Langmuir-type EDTA adsorption was proposed, in which the dissolution rate of malachite is
controlled by the removal of Cu(II)-EDTA complex from the malachite lattice. The proposed mechanism can explain the dependency
of the dissolution rate on EDTA concentration. The activation energies determined at pHs 5, 7.5, and 10 were found to be 51.4,
50.2, and 57.5 kJ mol−1, respectively. The calculated enthalpy changes of EDTA adsorption equilibrium were −43.2, −35.2, and −45.0 kJ mol−1 for pHs 5, 7.5, and 10, respectively. These values are in agreement with the proposed mechanism.
Formerly Graduate Student, Department of Metallurgy, Kyoto University, is
Formerly Professor, is Professor Emeritus, Department of Metallurgy, Kyoto University. 相似文献
957.
The activities of water, α(H2O), in the solution system of H2SO4-CuSO4-H2O were determined by an isopiestic method and those in the solution system of HCl-CuCl2-H2O by a transpiration method, both at 298 K. The activities of H2SO4 and H+ in the solution system of H2SO4-CuSO4-H2O were also determined at 298 K by the emf method. The water activities in both systems obeyed the Zdanovskii rule relatively
well. The α(H2O) experimentally determined in the sulfate system showed a satisfactory agreement with those calculated from the Robinson-Bower
equation, assuming the complete dissociations of H2SO4 and CuSO4, whereas a good agreement between the calculated and experimentally determined α(H2O) for the chloride system was obtained when the formation of Cu(II) chloro-complexes was taken into consideration. The mean
activity coefficients, γ±, of solutes, including H2SO4, HC1, and CuCl2 in these solution systems, were calculated at 298 K by the McKay-Perring method using the activity data. The γ±(H2SO4) values in the solution system of H2SO4-CuSO4-H2O were in good agreement with those determined by the emf method. On the other hand, the γ±(CuSO4) were calculated at the same temperature based upon the Gibbs-Duhem equation using both measured α(H2O) and calculated γ±(H2SO4) values, because of solubility limitations. 相似文献
959.
Hideo Hosono Yasuhiro Sakai Marcelo Fasano Yoshihiro Abe 《Journal of the American Ceramic Society》1990,73(8):2536-2538
Monolithic porous ceramics composed of TiO2 (67 mol%) and SiO2 (33 mol%) were prepared via casting a melt in the Na2 O-CaO-TiO2 -P2 O5 -SiO2 system and subsequent acid leaching of the resultant ceramics which are constituted of NaCaPO4 , TiO2 , and amorphous SiO2 . The median pore diameter and specific surface area of the resulting porous ceramics are approximately 1 μm and 40 m2 , respectively. Amorphous silica surrounds the submicrometer-sized particles of TiO2 acting as a binder and retaining monolithic forms. No significant shrinkage in the pore size occurred upon heating up to 1000°C. 相似文献
960.
Feng-Gang Lin Yuji Takao Yasuhiro Shimizu Makoto Egashira 《Journal of the American Ceramic Society》1995,78(9):2301-2306
Current ( I )-voltage ( V ) characteristics of porous ZnO varistors with different Bi2 O3 content have been investigated in air as well as in H2 -air mixtures in the temperature range room temperature (RT)-600°C. The I-V characteristics measured at RT remained unchanged in the presence of H2 , but the breakdown voltage clearly shifted to a lower electric field in the temperature range 400–600°C. The breakdown voltage decreased with increasing H2 concentration in air. The optimum amount of Bi2 O3 for the largest decrease was found to be 1.0 mol%. Thus, ZnO varistors can be used as a new type of H2 sensor. The results presented in this study also suggest the important role of excess oxygen ions existing at the ZnO-ZnO grain boundaries in developing the Schottky barrier as well as in the H2 -sensing mechanism of the varistors. 相似文献