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221.
Hiroyuki Hosokawa Koji Shimojima Hajime Iwasaki Mamoru Mabuchi 《Philosophical Magazine Letters》2013,93(11):713-718
Nanocrystalline and sub-microcrystalline samples of nickel have been machined by a focused Ga+ ion beam (30?keV and 187?pA) at doses of 8.92?×?1016?–?2.68?×?1018 ions/cm2 and their surface topography was investigated by atomic force microscopy (AFM). Values of the root-mean-square (RMS) roughness increase with increasing ion dose. The surfaces of the nanocrystalline Ni were smoother than those of the sub-microcrystalline Ni, indicating that smoothing due to diffusion for the former works more effectively than that for the latter. 相似文献
222.
M. Zhao 《Philosophical Magazine Letters》2013,93(3):229-236
Metallic glass has been formed in Au50Ta50 multilayer films upon 200?keV xenon ion mixing at an irradiation dose of 1?×?1015?Xe+/cm2. Electron diffraction and high-resolution transmission electron microscopy analysis confirm that the metallic glass consists of two amorphous phases, evolved from Au and Ta lattices, respectively, and also reveal the formation of a fractal morphology with a fractal dimension of 1.73?±?0.05 in the dual-phase glass features. In similar Au65Ta35 multilayer films, a fractal pattern is also observed at a dose of 1?×?1015?Xe+/cm2, while the pattern, with a fractal dimension of 1.74?±?0.05, is composed in this case of a crystalline Au-based solid solution and a Ta-based amorphous phase. Interestingly, the fractal dimensions of the two irradiation-induced fractal patterns match quite well with that expected on a cluster diffusion-limited aggregation model. 相似文献
223.
ABSTRACTPoly(methyl methacrylate) films and poly(methyl methacrylate)/fullerene composite films were fabricated by casting from toluene solutions. The mass fraction of fullerene (C60) was varied from 0.05–3?wt. %. The effect of the fullerene (C60) content on the thermal degradation parameters of the composite films was evaluated by thermogravimetric (TG) analysis. It was found that the incorporation of C60 improved the thermal stability of the polymers. The films eventually decomposed in three stages. Incorporation of fullerene caused a change in the distribution of mass loss over the stages of degradation in comparison with the pristine polymer. Using differential scanning calorimetry (DSC), the phase transitions from the glassy state to the elastic one was studied for the examined polymeric materials. New data relating to the effect of C60 on the glass transition temperature of composites with low weight fractions of filler were obtained. Specifically, for films containing up to 0.1 wt. % of C60, a single glass transition temperature was found, whereas for composites with a higher concentration of filler, two glass transition temperatures were recorded. 相似文献
224.
Building on an existing latent variable analysis of executive function (EF) in children (N = 191, 57% boys and 43% girls) making the transition to school (Hughes et al. (2010), Developmental Neuropsychology, vol. 35, pp. 20-36), the current study both documented average developmental improvements from 4 to 6 years of age and examined individual differences in EF growth in relation to latent factors for two sets of child outcome measures at 6 years: (a) first-grade teachers’ ratings of emotional symptoms, hyperactivity, and conduct/peer problems and (b) children’s self-perceived academic and social competencies. With effects of concurrent verbal ability and EF controlled, variation in EF slopes across the transition to school predicted variation in latent constructs for (a) all four problem behavior subscales and (b) children’s self-reported academic (but not social) competence. These findings underscore the clinical and educational significance of early individual differences in EF and highlight the value of adopting a developmental perspective. 相似文献
225.
Liat Kulik 《Sex roles》2003,48(5-6):205-215
This paper presents a study on morning passages from home to work. The sample consisted of 226 Israeli parents working in managerial positions (136 men and 90 women). Eighty percent of the participants were Israeli-born, and the rest immigrated to Israel at a young age. In the study, I examined gender differences in emphasis on domestic and work activities at 3 main transitional stages in the morning: home transitions (30 min before leaving for work), on the way to work, and at work (the first 30 min after arrival at work). The findings indicate that in the home-transition women focused more on domestic tasks than on work tasks, whereas men showed the opposite tendency. On the way to work, women tended to intensify their involvement in work activities, but remained strongly concerned with domestic activities. Men, however, focused primarily on work tasks during this transition. In the work transition, both men and women were more concerned with work tasks than domestic tasks. Therefore, even though men and women focused on different tasks in the initial transition, by the time they arrived at the workplace, they were immersed to the same extent in work activities. Furthermore, the participants' age, children's ages, and years of marriage correlated negatively with emphasis on domestic tasks during the home transition regardless of gender. 相似文献
226.
This study examined differences on major aspects of attaining adult status in the transition from adolescence into young adulthood. The attainment of developmental tasks and the quality of parent–child relationships were compared across adolescence and young adulthood. In addition, the extent to which relationships with parents are related to the attainment of young adulthood developmental tasks was also investigated. The study was conducted on 169 Israeli adolescents, early young adults, and late young adults. Results showed that developmental tasks are attained at different stages, and that the consolidation of adult status is achieved closer to the end of the third decade of life. Relationships with parents were found to be more positive following the transition from adolescence to early young adulthood. Adaptation of young adults was explained by the quality of relationships with parents and especially with fathers. 相似文献
227.
论传统义利观和诚信观的现代转换——从“以诚实守信为荣,以见利忘义为耻”谈起 总被引:1,自引:0,他引:1
重义轻利是传统社会的基本价值取向,国人的义利观经历了一个从长期的“羞于言利”到逐渐面对市场逐利,再到一部分人重利轻义、见利忘义的历史转化过程;今天,应改变传统义利观中义与利相互对立的状态,倡导一种义利并重、道义与功利协调发展的新型义利观。诚实信用既是我国传统道德的基本规范,又是市场经济、法制经济的必然要求,从而具有道德建设和法制建设的二重性;法律原则要以其本身所包含的道德合理性为价值基础,而良法的实施又离不开相应的社会道德环境的配合。在市场化和法制化背景下,应该既依托传统,又立足现实,实现传统义利观和诚信观的现代转换。 相似文献
228.
Transition from School to Adult Life: Empowering Youth Through Community Ownership and Accountability 总被引:1,自引:0,他引:1
Constance M. Lehman Hewitt B. Clark Michael Bullis Judith Rinkin Louis A. Castellanos 《Journal of child and family studies》2002,11(1):127-141
The evolution of transition services for youth with disabilities illustrates the transformation that has occurred from a systems-driven to a youth-centered support approach. This article documents how this shift has occurred. We review research that has influenced the direction of national policies and practices. A chronology of the policies that best represent the seminal foundation for current transition best practices for youth with emotional disturbance (ED) is presented. The field of special education led the way toward articulating the new vision for providing transition support by defining services as the coordination of multiple systems to address life domains (e.g., post-secondary education, employment, independent living, and community adjustment). Promising practices, within the context of the conversion to an ecological model of support that contributes to youth self-determination, include utilization of a youth-centered, strengths-based approach to transition planning, beginning in the middle school years. There remain significant barriers to adoption of the practices that may best support the successful transition of youth. These include lack of coordinated efforts across systems, socioeconomic, and community factors. Committed actions by government, the business sector, and private citizens are essential to address these challenges. 相似文献
229.
Russell Taylor Douglas Elliffe Christopher A. Podlesnik Sarah Cowie 《Journal of the experimental analysis of behavior》2019,111(2):274-288
We introduce to behavior analysis a way of analyzing choice behavior that exploits recent developments in nanoeconomics, financial economics, and econometrics. A response return, modeled on an economic return, is the log differenced count of responses allocated to each of two alternatives during a short time window, compared with that in the immediately preceding window. The response return is a new dependent variable which offers a novel and useful way of looking at operant behavior, especially at the molecular level of analysis. The response–return series is a near‐instantaneous measure of an organism's dynamic preferences for each of two alternatives. Analyzing such a series requires time‐analytic techniques, including Auto‐Regressive Conditional Heteroskedastic (ARCH) models. We illustrate these techniques by analyzing choices between combinations of arithmetic and exponential variable‐interval schedules with pigeon subjects. All response–return series were well‐fitted by one of three ARCH‐family models. The fitted models were differentially sensitive to transition versus steady‐state data samples. The particular insights that the ARCH analyses offer are improved understanding of the effects of the instantaneous effects of reinforcers and their absence, of how the distribution of reinforcers in time affects choice, and of the differences between choice in transition and at steady state. 相似文献
230.
Stephanie Alves Anne Milek Guy Bodenmann Ana Fonseca Maria C. Canavarro Marco Pereira 《Personal Relationships》2019,26(2):286-309
This study explored the mediating role of common dyadic coping (common DC) on the longitudinal associations between attachment‐related anxiety and avoidance and parental adjustment to the first year postpartum. A total of 92 Portuguese couples completed self‐report questionnaires of romantic attachment, common DC, parenting stress, and parental confidence. Results showed that more avoidant parents (at mid‐pregnancy) engaged less in common DC (at 6 weeks postpartum), which consequently increased their partner's parenting stress (only in mothers) and decreased their partner's parental confidence (in both parents) at 6–9 months postpartum. Anxious attachment did not predict parents' adjustment directly or indirectly. Interventions aimed at preventing adjustment difficulties to early parenthood in more avoidant parents should focus on enhancing their common DC strategies soon after childbirth. 相似文献