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51.
A widespread assumption in theories of emotion is that there exists a small set of basic emotions. From a biological perspective, this idea is manifested in the belief that there might be neurophysiological and anatomical substrates corresponding to the basic emotions. From a psychological perspective, basic emotions are often held to be the primitive building blocks of other, nonbasic emotions. The content of such claims is examined, and the results suggest that there is no coherent nontrivial notion of basic emotions as the elementary psychological primitives in terms of which other emotions can be explained. Thus, the view that there exist basic emotions out of which all other emotions are built, and in terms of which they can be explained, is questioned, raising the possibility that this position is an article of faith rather than an empirically or theoretically defensible basis for the conduct of emotion research. This suggests that perhaps the notion of basic emotions will not lead to significant progress in the field. An alternative approach to explaining the phenomena that appear to motivate the postulation of basic emotions is presented. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
The present study examined the relation between individual cognitive structure and several key career decision variables. Specifically, in a sample of college students enrolled in a career development class, the usage of the RIASEC (Realistic, Investigative, Artistic, Social, Enterprising, and Conventional) circumplex (adherence) was examined as it varied across individuals and with career certainty, career decision-making self-efficacy, and interest-occupation congruence. Individual adherence to the RIASEC circumplex as a cognitive structure was related to better career decision outcomes. Changes in adherence as a function of taking a career class were found to be associated with changes in career certainty, career decision-making self-efficacy, and interest-occupation congruence. The results support the importance of thinking about careers in a manner similar to the RIASEC circumplex and the potential value of direct instruction of this model. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Aicha Loucif Roberto B. Figueiredo Megumi Kawasaki Thierry Baudin Fran?ois Brisset Rafik Chemam Terence G. Langdon 《Journal of Materials Science》2012,47(22):7815-7820
Experiments were conducted to evaluate the microstructural evolution in a commercial Al-0.6 % Mg-0.4 % Si alloy processed using high-pressure torsion for up to 20 turns. Disks of the alloy were tested in two different conditions: in a solution-treated condition and after a short aging treatment at 523 K. The results show that HPT processing introduces significant grain refinement through HPT processing including a reduction in grain size from ~150 μm to ~720 nm in 1 turn of HPT. The final grain size in this alloy was ~250 nm after 20 turns. Some tensile tests were conducted to evaluate the mechanical properties of the alloy at the solution treatment temperature. The results from these tests show that aging at 523 K leads to a small increase in ductility for all tensile samples with a maximum recorded elongation of ~230 %. 相似文献
56.
Wei Xu Roberto B. Figueiredo Xiaolin Wu Simon Pauly Mihai Stoica Jürgen Eckert Terence G. Langdon Kenong Xia 《Advanced Engineering Materials》2011,13(12):1108-1113
A nanocrystalline bcc Ti67.4Nb24.6Zr5Sn3 alloy is shown to fracture in an intrinsically ductile manner with exceptionally large dimples (up to 10 µm) which are two orders of magnitude greater than the grain size (≈ 40 nm). This large plasticity length scale is attributed to a combination of low shear modulus (≈ 27 GPa), high Poisson's ratio (≈ 0.4) and ultrahigh strength (UTS ≈ 1.1 GPa), close to the ideal shear stress, which facilitates ideal shear deformation to promote transgranular shear. 相似文献
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Ultrafine-grained, and even nanostructured materials can be manufactured by ultra-high straining by equal-channel angular pressing (ECAP), high-pressure torsion (HPT), by machining, and through combinations, such as machining of ECAP specimens, HPT plus ECAP, and HPT of machining chips. This report describes the results of investigations of the microstructure and microtexture of pure aluminium and copper subjected to different deformation processes to high imposed strains. The microstructures, dislocation densities, and microhardness developed during combinations of different strain paths were investigated and all characteristics were analyzed by X-ray, transmission and scanning electron microscopy, and by orientation imaging microscopy. The influence of different processing routes is examined in terms of the accumulated strain and microstructure refinement. A saturation in grain refinement is also considered with reference to the occurrence of recovery during ultra-high strain deformation. 相似文献
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In this study we explored the temporal patterning of intoxication and exposure to a stress-producing situation on alcohol's effects on stress. 40 male social drinkers received either a 0.7 g/kg dose of alcohol or a placebo. When exposure to a social stressor preceded intoxication, a significant alcohol-induced increase in heart-rate reactivity was found. When intoxication preceded exposure to the stressor, conventional analysis of the data indicated a stress-dampening effect of alcohol on heart rate. No differences were obtained from self-reports of anxiety in either pattern. The findings are explained in terms of attentional and cognitive-encoding processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Superplasticity in ceramics 总被引:1,自引:0,他引:1
It is now recognized that superplasticity is a potential deformation process in ceramics. This review summarizes the major characteristics of superplasticity and examines the reports of both transformation and structural superplasticity in ceramic and other non-metallic materials. It is shown that there are both similarities to and differences from metals. Similarities include the variation of strain rate with stress and grain size, but an important difference is the necessity to consider the role of intergranular glassy phases in ceramics. Superplasticity is also important in intermetallic compounds, and in geological materials where there is evidence for superplastic deformation both in laboratory experiments and in natural deformation. 相似文献