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121.
Takuji Kobayashi Katsuhiko Sasaki 《Journal of Materials Science: Materials in Electronics》2009,20(4):343-353
This paper discusses uniaxial ratchetting deformation of lead-free solder alloy Sn–3Ag–0.5Cu and lead-containing solder alloy
Sn–37Pb, which were subjected to tension–compression loading with several stress amplitudes and stress ratios, minimum stress
over maximum stress. First the uniaxial ratchetting tests were conducted with three maximum stresses and four stress ratios.
All tests were conducted using cylindrical bulk specimens of the solder alloys at 313 K. The test results show that there
are differences in the ratchetting deformation behavior of the two solder alloys; the larger ratchetting strain occurs in
the lead-containing solder alloy than in the lead-free solder alloy. The ratchetting deformation was simulated by the dislocation
based constitutive model proposed by Estrin et al. (J Eng Mater Technol 118:441, 1996). The evolution equation of the back
stress employed in the constitutive model was modified considering a dynamic recovery term. The effect of the modification
of the back stress evolution is discussed by comparing the simulations with the corresponding experimental results. The simulations
suggest that the recovery term in the kinematic hardening rule plays an important role in fitting the simulation to the experimental
results of the ratchetting deformation of the solder alloys. 相似文献
122.
Nguyen Thi Huong Lien Hajime Nobuhara Fangyan Dong Kaoru Hirota 《Signal, Image and Video Processing》2009,3(2):115-126
To robustly and imperceptibly embed copyright information as a watermark into music clips, a two channel digital watermarking
system based on the least significant bit (LSB) method and echo hiding (EH) with a new exponential time-spread echo kernel
(ETEK) is proposed. By spreading the echo so that it seems like natural room reverberation, as well as the use of two channels
to separately watermark by the LSB method and the EH method which have complementary characteristics, the system provides
satisfactory sound quality and exhibits both efficient retrieval capacity and robustness against attacks. Experiments show
that the proposed system retrieves watermarks with 100% accuracy for all clips and is almost imperceptible. With a set of
42 attacks supplied by the StirMark Benchmark for Audio (SMBA), the proposed system has an average robustness of 0.98 where
the ideal value is 1.00, and higher than any conventional methods. With these results, the proposed system is shown to be
possible for the application to music distribution over the Internet. 相似文献
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124.
Kaoru Abe Yasuhiro Sakurai Akira Okuyama Kazuhiro Sasaki Kei Tawarada 《Journal of the science of food and agriculture》2009,89(6):1097-1100
BACKGROUND: The behavior of cadmium in ecosystems needs to be monitored because of the human toxicity of this heavy metal. The need recently arose for a simple and quick on‐site test for trace levels of Cd in food and environmental samples. In response, an immunochromatographic assay kit for detecting Cd was manufactured by Kansai Electric Power Co. of Japan. This kit uses the antigen–antibody complex reaction between the Cd–EDTA complex and an anti‐Cd–EDTA antibody and shows the results in terms of the degree of color developed on a test paper. We previously reported the successful use of this kit to determine Cd concentrations in brown rice. Here, we applied the kit to the determination of Cd concentrations in rice foliage and soil. RESULTS: Cadmium in rice foliage was not extracted successfully by the method used for brown rice. However, it was successfully extracted by 0.1 mol L?1 HCl solution at a rice foliage:HCl ratio of 1:20, and coexisting metals were removed sufficiently by the column treatment. The Cd concentrations determined by immunochromatographic assay were well correlated with the values obtained by acid decomposition and inductively coupled plasma mass spectrometry. The 0.1 mol L?1 HCl‐extractable Cd concentration in soil was also determined successfully with the kit. CONCLUSION: Approximate Cd concentrations in rice plants and 0.1 mol L?1 HCl‐extractable Cd concentrations in soil can be monitored easily and quickly by this method at locations where facilities for acid digestion and precision analysis are not available. Copyright © 2009 Society of Chemical Industry 相似文献
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127.
Annealing Effect in GaDyN on Optical and Magnetic Properties 总被引:1,自引:0,他引:1
Yi-Kai Zhou Masahiro Takahashi Shuichi Emura Shigehiko Hasegawa Hajime Asahi 《Journal of Superconductivity and Novel Magnetism》2010,23(1):103-105
The annealing effect on the optical and magnetic properties of the GaDyN layers was studied. The PL intensities of yellow
and green bands as well as the intra-4f orbital transition of Dy3+ ions were found to decrease for the samples annealed at 900 and 1000 °C. It is supposed that the intra-4f orbital transition is related to the broad peak luminescence coming from defects. Increasing the annealing temperature, the
magnetization becomes smaller. It is considerable that the number of electrons coming from defects was reduced by the annealing
treatments and that the ferromagnetism in GaDyN is attributed as carrier induced ferromagnetism. 相似文献
128.
129.
Yury Kapelyushin Yasushi Sasaki Jianqiang Zhang Sunkwang Jeong Oleg Ostrovski 《Metallurgical and Materials Transactions B》2017,48(2):889-899
Reduction of un-doped magnetite is developed topochemically with the formation of a dense iron shell. However, the reduction of alumina-doped magnetite to wüstite proceeds with the formation of a network-like structure which consists of criss-crossed horizontal and vertical plates of wüstite. Reduction of magnetite includes the conversion of Fe3+ to Fe2+ and the movement of iron cations from the tetrahedral sites on the {400} and {220} planes of magnetite to the octahedral sites on the {200} planes of wüstite. Alumina has a negligibly small solubility in wüstite. In the reduction of magnetite doped with Al2O3, rejected Al3+ cations from wüstite diffuse to the magnetite–hercynite solid solution. Enrichment of the Fe3O4–FeAl2O4 solution with alumina in the vicinity of the reduction interface restricts the growth of {220} planes of wüstite and nucleation of {220} planes adjusted to the existing planes, preventing the merging of wüstite plates during the reduction process. Reduction of magnetite from the magnetite–hercynite solid solution practically stops when the Al3+ content at the interface approaches the solubility limit. Wüstite in the separated plates is reduced further to iron. 相似文献
130.