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951.
J.J. Wang S. Bhattacharyya Q. Li T.W. Heo X.Q. Ma Long-Qing Chen 《Philosophical Magazine Letters》2013,93(7):327-335
An efficient numerical algorithm is proposed to accurately compute the elastic fields in two-dimensional (2D) or three-dimensional (3D) microstructures with arbitrary elastic inhomogeneity and anisotropy. It combines the equivalent inclusion method of Eshelby, the microelasticity theory of Khachaturyan, and the spectral iterative perturbation method of Hu and Chen. Its efficiency is compared with those of existing approaches in the literature. The method can be conveniently implemented in phase-field modeling of stress-dependent microstructure evolution and/or of mass/electrical transport. 相似文献
952.
The role of immiscible Cu/Mo interfaces on the formation of helium (He) bubbles in ion-irradiated Cu/Mo 5?nm multilayers is examined. Interfaces significantly enhance the critical He concentration above which bubbles, approximately 1?nm in diameter, are detected via through-focus imaging in a transmission electron microscope. He-to-vacancy ratio affects the formation and distribution of He bubbles. The diameter of He bubbles in Cu appears to be slightly larger than that in Mo. 相似文献
953.
Chunfei Li Junji Saida Mitsuhide Matsushita Akihisa Inoue 《Philosophical Magazine Letters》2013,93(9):621-626
The crystallization process of a Hf59Ni8Cu20Al10Ti3 相似文献
954.
Gong Li Y.P. Gao Z.H. Chi J. Liu T. Zhang R.P. Liu 《Philosophical Magazine Letters》2013,93(7):543-551
A 52 m drop tube has been used to solidify bulk-glass-forming Zr41Ti14Cu12.5Ni10Be22.5 alloy. Glassy balls with different sizes solidified from the droplets whose structural features, glass-transition behaviour and crystallization kinetics have been investigated. The results indicate that the apparent activation energies of the glass transition and main crystallization reaction are significantly different from those of samples prepared by water quenching. The structural difference between the two types of glassy specimen is revealed by compression studies and in situ energy-dispersive X-ray diffraction. The results are important for understanding the structural features of bulk-forming glasses. 相似文献
955.
The effects of irradiation with electrons having energies in the range 0.7–1.7 MeV on the dark conductivity and the network of hydrogenated amorphous silicon (a-Si:H) thin films have been studied. The dark conductivity measurements show that electron irradiation leads to a degradation in the dark conductivity, with the degradation being greater at lower electron energies. The Raman results suggest that the irradiation induces structural defects in the a-Si:H films, with the lower energy electrons producing more disorder in the amorphous network. 相似文献
956.
The present study explores stigma against rural‐to‐urban migrants in China, drawing on a dialogical approach. It investigates the processes of stigmatization from two sides: that of the stigmatizer and that of the stigmatized. Open‐ended individual interviews were conducted with 138 participants (60 urban residents and 78 rural‐to‐urban migrants) in Tianjin, China. Findings from this study indicate that migrants were stigmatized by urban residents as having an unattractive physical appearance, potential perils of disease or crime, and discredited places of origin. Such stigma was embedded in China's unique hukou system and generated from a social categorization of superior and inferior groups. Migrants reported a number of coping strategies to counter such stigma: blaming fate, stigma reversal and upward mobility. However, migrants did not view themselves contemptuously and expressed positive feelings about their lives as migrants. They regarded internal migration as a way of pursuing happiness. Overall, urban residents stigmatized migrants legitimated by the hukou system, while migrants were surprisingly resilient against stigma, and did not internalize it, due to their economics‐driven internal migration. This study underscores that stigma in a given society is dialogically interdependent with its socio‐cultural context and that the perspectives of both the stigmatizer and the stigmatized need to be taken into consideration. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
957.
958.
The interaction between a dislocation and an elliptical hole in icosahedral quasicrystals is considered. An explicit expression for the complex potential is derived using the extended Stroh formalism. Based on the conformal mapping method and a perturbation technique, closed-form solutions are obtained. The field intensity factors at a crack tip and the image forces on the dislocation arising from the crack are calculated. The effects of phonon–phason elastic coupling on the mechanical behavior are also observed. 相似文献
959.
H. Li F. Yin T. Sawaguchi K. Ogawa X. Zhao K. Tsuzaki 《Philosophical Magazine Letters》2013,93(5):348-357
A dominant Goss texture component instead of a Brass texture component has been observed in a warm-rolled Fe–28Mn–6Si–5Cr shape memory alloy [H. Li, F. Yin, T. Sawaguchi K. Ogawa, X. Zhao and K. Tsuzaki, Mater. Sci. Eng. A 494 (2008) p.217]. In order to clarify the orientation flow mechanism in these grains of Goss orientation, investigations on microtexture and microstructure were carried out by electron backscattering diffraction (EBSD) and transmission electron microscopy (TEM). It is concluded that the Goss–Brass orientation transformation is restrained in the Goss-orientated grains, which were widely observed in both the deformed matrix and shear bands. 相似文献
960.
Loretta F. Li 《Journal of Research on Christian Education》2013,22(1):108-109
This study will explore the omission of the Tower of Babel narrative from middle and secondary school world history, world studies, and world geography textbooks and will consider what might be learned from inclusion of the story in the curriculum. A total of 17 textbooks are analyzed. The Tower of Babel narrative is examined within the context of the Book of Genesis, and The Epic of Gilgamesh. 相似文献