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41.
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We report the study of the effect of strain rate on the compressive behaviour of a Zr56Al10.9Ni4.6Cu27.8Nb0.7 bulk metallic glass. The results indicated that both the strength and plasticity of the glass increase with increasing the strain rate up to 10?5 s?1, above which the strength and plasticity start to decrease. The enhanced mechanical properties under a strain rate of 10?5 s?1 are due to the emission/propagation rate of the shear bands being consistent with the strain rate. 相似文献
43.
Won Seok Chang Sun-Ah Song Yun Hwangbo Jae-Hyun Kim Hak-Joo Lee 《Philosophical Magazine Letters》2013,93(8):391-398
Carbon nanotubes have been intensively studied owing to their great potential in nanoelectronics and nanomechanical devices. Recently, experimental results have shown that single-walled carbon nanotubes (SWCNTs) change their electronic properties when subjected to strain. In this study, the electromechanical characteristics of SWCNT networks were investigated for the application of printable strain sensors on flexible substrates. SWCNT films were formed on plastic substrates of poly(ethylene terephthalate) using a spray process. In this manner, we were able to control the transparency and obtain uniform electrical properties of the films. The films are isotropic on account of the random orientation of bundles of SWCNTs. Experimental results showed a nearly linear change in the resistance across a film when it was subjected to tensile strain, even in the inelastic range of the flexible substrate. The results demonstrate the potential use of SWCNT films for highly sensitive printable strain sensors on a macroscale. 相似文献
44.
Jianming Zeng Chenglu Lin Zhitang Song Kun Li Jinhua Li 《Philosophical Magazine Letters》2013,93(2):119-124
Lead zirconate titanate (PZT) (Pb(Zr0.52Ti0.48)O3) and barium titanate (BaTiO3) thin films have been successfully prepared using a novel sol-gel- hydrothermal (SG-HT) technique at low temperatures, which involves a combination of the conventional sol-gel process and a hydrothermal method. Highly (111)-oriented PZT thin films with a single perovskite phase and polycrystalline BaTiO thin films with well developed crystallites were obtained at a processing temperature as low as 1600C. The microstructural characteristics demonstrate that the SG-HT-derived PZT and BaTiO3 thin films with good crystallinity and surface morphology are converted from the amorphous phase to the desired perovskite phase on platinum-coated and bare silicon substrates at a low processing temperature of 100-200 C. These results suggest that the SGHT technique, which is of great significance because of its low processing temperature, will become a potential and promising process for fabricating PZT, BaTiO3 and other oxide thin films. 相似文献
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We report two experiments in which participants categorized target words (e.g., BLOOD or CUCUMBER) according to their canonical colour of red or green by pointing to a red square on the left or a green square on the right. Unbeknownst to the participants, the target words were preceded by the prime words “red” or “green”. We found that the curvature of participants’ pointing trajectories was greater following incongruent primes (green–BLOOD) than it was following congruent primes, indicating that individuals initiated a response on the basis of the prime and then corrected that response mid-flight. This finding establishes that the processing of masked orthographic stimuli extends down to include the formulation of an overt manual response. 相似文献
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Sarah Song 《Journal of applied philosophy》2016,33(4):450-456
Carens has done more than any other political theorist or philosopher to develop the normative perspective of prospective migrants from within the liberal democratic tradition, but he has not sufficiently engaged with the other side of the argument – in particular, with the value of political community and the principle of collective self‐determination. What is at stake for the immigrant‐receiving country that might justify its claim to control immigration? I first examine Carens’ theory of social membership and its connection to political community. I then discuss his method of ‘political theory from the ground up’ and his interpretation of democratic principles. I conclude with a discussion of the principle of collective self‐determination. 相似文献
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The Youn Scale was used to assess aging Koreans' perceived conflicts in relationships with their adult offspring. The sample consisted of 623 elderly Koreans between the ages of 55 and 84 years. Results indicated that aging Koreans experienced significantly more conflicts in their relationships as they grew older. There were also differences in the perceptions of problems in relationships with their offspring between those who lived together with their adult children and the those who did not, and also between those who were married and those who were single. The findings imply that aging Koreans want to have qualitatively better (i.e., warmer and closer) relationships with their offspring, regardless of their bereavement status and cohabitation status. 相似文献