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71.
Abstract A quasicrystalline Al-Fe phase has been formed by room-temperature ion mixing of AI-Fe multiple layers with no additional postannealing. The quasicrystalline phase was dispersed as grain in an amorphous matrix. The size of the grains was about 10-30nm, and the composition was determined to be Al80Fe20. The structure of the quasicrystalline phase was identified by calculating some 20 sharp diffraction rings in the selected-area diffraction pattern and found to be similar to that of the rapidly quenched AI-Mn quasicrystalline phase. 相似文献
72.
Y. Z. Liu X. T. Zu J. Lian L. Wang X. Q. Huang Z. G. Wang 《Philosophical Magazine Letters》2013,93(11):705-712
Ti–Al–Zr alloy has been oxidized at 360°C in alkaline steam at a pressure of 10.3?±?0.7?MPa. Cross-sectional transmission electron microscopy (TEM) observations indicated that the oxide scale of Ti–Al–Zr alloy was composed of outer and inner subscales, in which the outer layer consists of anatase-TiO2 and the inner layer a mixture of TiO and Ti2O. The thickness of the Ti2O, TiO and anatase-TiO2 were approximately 50, 100 and 400?nm, respectively. These results were confirmed by X-ray energy dispersive spectrometry (EDS) measurements. The enhanced corrosion of titanium alloys in LiOH solution is attributed to a high hexagonal Ti2O to tetragonal TiO2 phase transformation rate induced by the substitution of Li+ for Ti4+ in the oxide layer. 相似文献
73.
The compressive deformation and fracture features of Zr59Cu20Al10Ni8Ti3 bulk metallic glassy samples with aspect ratios in the range of 0.67–2.00 have been investigated. The compressive plastic strain of the glass monotonically increases with decreasing aspect ratio, but the maximum strength almost maintains a constant value of 1.77–1.88?GPa. All the compressive shear-band angles are equal to?~40° if modified by the rotation of the primary shear bands. 相似文献
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75.
The grain size variation in a gradient surface produced by a punching and recovery process on a Cu-30Ni alloy has been observed by atomic force microscopy. The friction characteristics of the gradient surface in a 3.5 wt% NaCl solution were investigated using a micro-indenter probe, a pin-on-disc type tribometer, a strain sensor and an optical microscope. The results showed that the hardness and grain size can be well represented by the Hall–Petch relationship when the gain size is more than 30?nm. The wear rate, friction coefficient and adhesive force all increase depth below the surface. These variations are attributed to a gradual increasing grain size with depth. The morphologies of the worn track were also studied to understand further the corrosive wear behaviour of gradient surfaces. 相似文献
76.
This brief report presents an experiment testing the effect of immersion on emotional responses and cognitive genre categorisation of film viewers. Immersion of a film presentation was varied by presenting an animated movie either in a 3D-viewing condition (low immersive condition) or in a CAVE condition (high immersive condition, comparable to virtual reality experience). Viewers rated their emotions and categorised the movies into four basic film genres (action, drama, comedy, and non-fiction). Two distinct types of emotion were measured: Fictional World emotions (e.g., sadness) in response to the presented fictional events and Artefact emotions in response to the film as an artefact (e.g., fascination). Results showed that stronger immersion led to more intense emotions but did not influence genre categorisation. In line with expectations, both types of emotional response were intensified by high immersion. The results are explained by suggesting that highly immersive cinema has its impact on a basic dimension of emotion, namely arousal that underlies both types of emotions. 相似文献
77.
Armando X. Estrada Tahira M. Probst Jeremiah Brown Maja Graso 《Military psychology》2013,25(2):220-236
We use classical test theory (CTT) and item response theory (IRT) methodologies to examine the psychometric and measurement properties of an instrument designed to assess sexual orientation harassment among military personnel (N?=?71,989). CTT analyses indicated that items were unidimensional and exhibited adequate levels of reliability. IRT analyses demonstrated that the items functioned similarly and exhibited appropriate levels of item discrimination. However, the analyses also suggested that the sensitivity of the items may be limited. Differential test functioning analyses provided evidence of the measurement equivalence of the instrument across male and female respondents. The findings provide support for the psychometric properties and measurement equivalence of the instrument for measuring sexual orientation harassment among male and female military personnel. We discuss the implications of our findings for future research on sexual orientation harassment in the workplace. 相似文献
78.
Ya Hui Michelle See Greta Valenti Angeline Y. Y. Ho Michelle S. Q. Tan 《European journal of social psychology》2013,43(6):570-584
This research explores when and how tailoring messages to attitudinal bases backfires. Study 1 demonstrated that for attitudes (toward education subsidies) that were based more on beliefs than emotions, recipients whose initial attitudes were incongruent with the message position (i.e., message opponents) showed mismatching effects, such that the affective message was more persuasive than the cognitive message. Study 2 replicated these mismatching effects among message opponents for attitudes (toward a rival university) that were primarily affective. Study 3 controlled for effects of initial attitude certainty and replicated the mismatching effects of Study 2 for affective attitudes toward an increase in tuition. Finally, Study 4 suggested a potential mechanism for mismatching effects, revealing that for attitudes (toward an online course management system) that were based more on beliefs than emotions, message opponents counter‐argued with the cognitive appeal more intensely than the affective appeal. Contrary to the notion in the extant literature that mismatching effects are relatively rare compared with matching effects, the current research suggests that mismatching effects occur for both primarily affective and cognitive attitudes when the recipient is highly opposed to the message position. The present findings also demonstrate the utility of examining attitudinal bases at the object level in the context of message tailoring. Implications for message tailoring and for affective versus cognitive attitudes are discussed. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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80.
S. X. Dou J. P. Zhou N. Savvides A. J. Bourdillon C. C. Sorrell N. X. Tan 《Philosophical Magazine Letters》2013,93(2):149-153
Abstract Superconducting and mechanical properties of Y1 Ba2Cu3 O7 can be improved by the use of sintering aids. 0·2 wt% of finely divided laser-ablated platinum powder has been mixed with the parent material and produced a dense product with exaggerated grain growth and improved critical current density and Vickers hardness. At higher concentrations of platinum, while the mechanical properties are further improved, the increased density appeared to inhibit access of oxygen for the tetragonal to orthorhombic phase transition and the current density was reduced. 相似文献