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681.
Defect formation in Nd2Fe14B grains, caused by a low-pressure-pack-sublimation Zn coating process, has been investigated. The results indicate that, in the Zn-affected region, low-angle boundaries decorated with precipitates form within the Nd2Fe14B grains. Zn, which is almost insoluble in Nd2Fe14 相似文献
682.
Measurements of static permittivity, refractive index and density have been carried out to study possible H-bonded complexes in solutions of anisole diluted by benzene together with high-static-permittivity alcohols, i.e. cyclohexanol, n-butanol, tert-butanol, isopropyl alcohol and 1-hexanol. The experiments were performed at 303 K. Dipole moments of the mixtures are calculated from the experimental data and these are used to obtain dipolar increments. The concentration ratio of proton donor to proton acceptor is plotted against a parameter, ΩB, which is determined from experimental data. From the plot, the dipole moment of the mixture and that of the component B are determined. The order of the complex can be obtained from the nature of the graph. The investigation shows that the interaction between the two components arises solely from a polarization effect. 相似文献
683.
Y. You 《Philosophical Magazine Letters》2013,93(12):656-667
N atom is one of the most frequent foreign interstitial atoms in α-iron along with C atoms. The Fe–C potential has been well-developed and can reproduce many significant interactions of C with point defects present in α-iron. However, there exists no satisfactory Fe–N potential to describe the interactions of N with point defects. Here, we develop a many-body potential for N in α-iron. The potential parameters are determined by fitting to ab initio data, which includes energetics, configurations, and relaxations of Fe atoms close to N atom. This potential successfully describes the interactions of Fe–N across a wide range of defect environments. The potential employs the embedded atom method form and hence is appropriate for large-scale molecular dynamics simulation. 相似文献
684.
The Wentzel–Kramers–Brillouin method is employed to study the cut-off frequencies of the horizontal shear waves in a freestanding functionally graded piezoelectric–piezomagnetic material film with the electrically and magnetically open boundary conditions. An analytical solution, which could be used in analyzing the problems of various functionally graded materials, is proven to have high precision by analytical analysis and a numerical example. The results reveal that the set of cut-off frequencies is a series of approximate arithmetic progressions. A theoretical foundation based on the relationship between the cut-off frequencies and the materials’ gradient property is established for nondestructive evaluation. 相似文献
685.
Christopher Moore 《British Journal for the History of Philosophy》2013,21(6):1021-1046
Socrates does not use the Laws' Speech in the Crito principally to persuade Crito to accept his coming execution. It is used instead to persuade Crito to examine and work on his inadequate view of justice. Crito's view of justice fails to coordinate one's duties to friends and those to the law. The Laws' Speech accomplishes this persuasive goal by accompanying Crito’s earlier speech. Both start from the same view of justice, one that Crito accepts, but reach opposing conclusions. Crito cannot judge between the two appealing speeches. His understanding of justice is too confused for him to decide well how to help Socrates. His need to explain what happened the morning he visited Socrates will prompt him and others to examine this indeterminate view of justice. Socrates foregoes direct refutation because Crito will not abide that usual way of interrogation. Engaging in short question-and-answer conversation is not the only way to bring a person to aporia and the intention to examine oneself. Socrates does not here undermine his assertions in the Apology about his ignorance, lack of interest in teaching, constant philosophizing, and his belief that what he does is question, examine, and test those he talks to. 相似文献
686.
Simon Truwant 《International Journal of Philosophical Studies》2013,21(5):696-715
AbstractBoth Kant and Levinas state that traditional ontology is a type of philosophy that illegitimately forces the structure of human reason onto other beings, thus making the subject the center and origin of all meaning. Kant’s critique of the ontology of his scholastic predecessors is well known. For Levinas, however, it does not suffice. He rejects what we could call an ‘existential ontology’: a self-centered way of living as a whole, of which all philosophical ontology is but a branch. Alternatively, he presents an ethical way of living centered on ‘the Other’. Kant also, however, eventually turns to ethics to uncover a more fundamental domain of meaning. Hence, both thinkers ultimately agree about the primacy of ethics over theory. Despite this concurrence, Levinas nevertheless criticizes all aspects of Kant’s turn towards ethics: his reason for making this turn, the kind of critique that he applies to this domain, and the outcome thereof. These three points reflect Levinas’ more general critique that Kant did not succeed in overcoming ontological discourse. This paper shows how Kant can reply to, and overcome, each of Levinas’ three critiques. In this way, I reveal certain commonalities between these two thinkers that commentators still often overlook. 相似文献
687.
本研究对行政职业能力测验中的阅读理解分测验考查何种能力要素进行了深入探讨.研究一首先通过文献法初步概括出行政职业能力测验阅读理解的能力考查体系,进而使用出声思维的方法对该考查体系进行验证和补充,最后通过专家调查论证方法对其进行最终确定.结果表明,行政职业能力测验阅读理解考查了6种能力,分别是提取信息能力、理解意义能力、理解细节能力、分析结构能力、概括能力及推断能力,其中提取信息能力和理解意义能力是基础.在此基础上,研究二使用该能力框架选取合适的行政职业能力测验阅读理解题目,组成一套阅读理解测验,并借助认知诊断方法,通过专家标定测验的Q矩阵,利用实测数据对研究一构建的能力考查体系的完备性进行了验证. 相似文献
688.
William Wong Arnold R. Eiser Robert G. Mrtek Paul S. Heckerling 《The American journal of bioethics : AJOB》2013,13(3):W8-W22
Objective: To determine the usefulness of Q methodology to locate and describe shared subjective influences on clinical decision making among participant physicians using hypothetical cases containing common ethical issues. Design: Qualitative study using by-person factor analysis of subjective Q sort data matrix. Setting: University medical center. Participants: Convenience sample of internal medicine attending physicians and house staff (n = 35) at one midwestern academic health sciences center. Interventions: Presented with four hypothetical cases involving urgent decision making near the end of life, participants selected one of three specific clinical actions offered for each case. Immediately afterward and while considering their decision, each respondent sorted twenty-five subjective self-referent items in terms of the influence of each statement on their decision-making process. By-person factor analysis, where participants are defined as variates, yielded information about the attitudinal background the physicians brought to their consideration of each hypothetical case. We performed a second-order factor analysis on all of the subjective viewpoints to determine if a smaller core of shared attitudes existed across some or all of the four case vignettes. Factor scores for each item and post-sort comments from interviews conducted individually with each respondent guided the interpretation of ethical perspective used by these respondents in making clinical decisions about the cases. Measurements and Main Results: Second-order factor analysis on seventeen viewpoints used by physicians in the four hypothetical urgent decision cases revealed three moderately correlated (r 2 < 40%) subjective core attitudinal guides used broadly among all the cases and among sixteen of the seventeen original factors. Across all the cases, our participants were guided in general by: (1) patient-focused beneficence, (2) a patient- and surrogate-focused perspective that includes risk avoidance, and (3) best interest of the patient guided by ethical values. Economic impact on the physician, expediency in resolution of the situation, and the expense of medical treatment were not found to be influential determinants in this study. Conclusions: Q sorting and by-person factor analysis are useful qualitative methodological tools to study the complex structure of subjective attitudes that influence physicians in making medical decisions. This study revealed the subjective viewpoints used by our physician participants as they made ethically challenging treatment decisions. The three second-order factors identified here are grounded in current bioethical values as well as the personal traits of physicians. The participants' decision methods appear to resemble casuistry more than principle-based decision making. Generalizability of results will require further studies. 相似文献
689.
Roger E. Beaty Chris J. Burgin Emily C. Nusbaum Thomas R. Kwapil Donald A. Hodges Paul J. Silvia 《Consciousness and cognition》2013,22(4):1163-1173
In two studies, we explored the frequency and phenomenology of musical imagery. Study 1 used retrospective reports of musical imagery to assess the contribution of individual differences to imagery characteristics. Study 2 used an experience sampling design to assess the phenomenology of musical imagery over the course of one week in a sample of musicians and non-musicians. Both studies found episodes of musical imagery to be common and positive: people rarely wanted such experiences to end and often heard music that was personally meaningful. Several variables predicted musical imagery, including personality, musical preferences, and positive mood. Musicians tended to hear musical imagery more often, but they reported less frequent episodes of deliberately-generated imagery. Taken together, the present research provides new insights into individual differences in musical imagery, and it supports the emerging view that such experiences are common, positive, and more voluntary than previously recognized. 相似文献
690.