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231.
Abstract This Letter presents a solution of the problem of the real temperature of nanoparticles under conditions of electron microscope beam irradiation. It is shown that the average temperature of the nanoparticles (NPs) may increase to several hundred degrees depending on contact conditions with the substrate, the intensity of the beam and the size of the NPs. The temperature increases with NP size a according to the dependence: T α a2 for sufficiently small particles. 相似文献
232.
This letter presents the results of internal-friction measurements of Co 70 Fe 5 Si 15 B10 metallic glass at temperatures 400K h T h 700K and frequencies 0.01 Hz h f h 0.05Hz. It is shown that Maxwellian viscoelastic damping is predominant in this case. The nature of this damping is determined by irreversible structural relaxation. The kinetic relaxation law is derived. 相似文献
233.
P. Shang G. Yang I.P. Jones C.E. Gough J.S. Abell K. Nadarzinski 《Philosophical Magazine Letters》2013,93(9):741-745
The position of Dy in the unit cell of Bi2Sr2CaCu2Oy has been determined by a real-space method. This is compared with the reciprocal-space atom location by channelling-enhanced microanalysis (ALCHEMI) method. 相似文献
234.
Fuqian Yang 《Philosophical Magazine Letters》2013,93(3):185-193
Contact problems between two solids are essential to interpret the loading-unloading behaviour in indentation tests. Using linear elastic theory, a general relationship between the normal stress and the surface deformation for elastic contact of two solids was derived, in which the normal stress is a function of the mean curvature of the undeformed surface. 相似文献
235.
Yu.B. Bolkhovityanov A.S. Deryabin A.K. Gutakovskii L.V. Sokolov 《Philosophical Magazine Letters》2013,93(7):458-464
Edge misfit dislocations (MDs) formed as result of reactions between 60° glissile threading dislocations and 60° MDs lying on an intersecting glide plane were found in strained GeSi-on-Si(001) and Ge-on-InGaAs/GaAs films. It was demonstrated that dislocations penetrating from the InGaAs buffer layer to the strained Ge film can provoke formation of not only 60° MDs, but also edge MDs on the interface even at minor mismatch of the lattice parameters of the film and the InGaAs/GaAs virtual substrate. 相似文献
236.
Linda B. Smith Chen Yu Hanako Yoshida Caitlin M. Fausey 《Journal of cognition and development》2013,14(3):407-419
Head-mounted video cameras (with and without an eye camera to track gaze direction) are being increasingly used to study infants’ and young children's visual environments and provide new and often unexpected insights about the visual world from a child's point of view. The challenge in using head cameras is principally conceptual and concerns the match between what these cameras measure and the research question. Head cameras record the scene in front of faces and thus answer questions about those head-centered scenes. In this “Tools of the Trade” article, we consider the unique contributions provided by head-centered video, the limitations and open questions that remain for head-camera methods, and the practical issues of placing head cameras on infants and analyzing the generated video. 相似文献
237.
Xufeng Liu Yang Liao Luping Zhou Gang Sun Min Li Lun Zhao 《Cognitive, affective & behavioral neuroscience》2013,13(3):491-500
The aim of the present study was to investigate the time course of the positive advantage in the expression classification of faces by recording event-related potentials (ERPs). Although neutral faces were classified more quickly than either happy or sad faces, a significant positive classification advantage (PCA)—that is, faster classification for happy than for sad faces—was found. For ERP data, as compared with sad faces, happy faces elicited a smaller N170 and a larger posterior N2 component. The P3 was modulated by facial expressions with higher amplitudes and shorter latencies for both happy and neutral stimuli than for sad stimuli, and the reaction times were significantly correlated with the amplitude and latency of the P3. Overall, these data showed robust PCA in expression classification, starting when the stimulus has been recognized as a face revealed by the N170 component. 相似文献
238.
239.
Cardiomyopathy is a genetically and clinically heterogeneous, life threatening disease which affects people of all ages. Recent guidelines provide recommendations for cardiac screening and genetic testing in at-risk relatives, but the uptake and impact of these measures in the United States is unknown. This is a single institution retrospective study that characterizes the uptake of cardiac screening and genetic testing for relatives of a cohort of 57 probands with hypertrophic (HCM) and dilated cardiomyopathy (DCM) who underwent both clinical evaluation and genetic testing. Cardiac screening was indicated for 302 relatives. One hundred and seventy-three (57 %) completed cardiac screening. Forty of the 57 probands were mutation positive and genetic testing was indicated for 213 relatives. Eighty-four (39 %) completed genetic testing. The uptake of cardiac surveillance was greater than the uptake of genetic testing (p?<?0.0001) among relatives of mutation positive probands. Within the group of at-risk, asymptomatic relatives of probands, cardiac screening and genetic testing were positive in 25 % and 40 % of cases, respectively. These data demonstrate the important role and utility of cascade cardiac screening and genetic testing in the care of patients and families with HCM or DCM. The approach to cardiac screening and genetic testing should be family-specific and requires expertise in the genetics of cardiomyopathy. 相似文献
240.
Hongsheng Yang Fang Wang Nianjun Gu Xiao Gao Guang Zhao 《Psychonomic bulletin & review》2013,20(6):1176-1180
Eye-tracking technique and visual search task were employed to examine the cognitive advantage for one’s own name and the possible effect of familiarity on this advantage. The results showed that fewer saccades and an earlier start time of first fixations on the target were associated with trials in which participants were asked to search for their own name, as compared to search for personally familiar or famous names. In addition, the results also demonstrated faster response times and higher accuracy in the former kind of trials. Taken together, these findings provide important evidence that one’s own name has the potential to capture attention and that familiarity cannot account for this advantage. 相似文献