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1.
The metastable particles in an Al–Zn–Mg–Cu alloy have been examined at atomic-resolution using high-angle annular dark field (HAADF) imaging. In under-aged conditions, thin η′ plates were formed with a thickness of seven atomic planes parallel to the {111}Al planes. The five inner planes of the η′ phase appear to be alternatively enriched in Mg and Zn, with two outer planes forming distinct Zn-rich interfacial planes. Similar Zn-rich interfacial enrichment has also been identified for the η phase, which is a minimum 11-plane thick structure. In rare instances, particles less than seven planes were found indicating a very early preference for seven-layer particle formation. Throughout the aging, the plate thickness appears constant, while the plate radius increases and no particles between 7 and 11 planes were observed. Based on the HAADF contrast, our observations do not support the η′ models previously set forth by other authors. Clear structural similarities between η′ and η were observed, suggesting that drawing distinctions between η′ and η phases may not be necessary or useful.  相似文献   

2.
Rudas, Clogg, and Lindsay (1994, J. R Stat Soc. Ser. B, 56, 623) introduced the so-called mixture index of fit, also known as pi-star (π*), for quantifying the goodness of fit of a model. It is the lowest proportion of ‘contamination’ which, if removed from the population or from the sample, makes the fit of the model perfect. The mixture index of fit has been widely used in psychometric studies. We show that the asymptotic confidence limits proposed by Rudas et al. (1994, J. R Stat Soc. Ser. B, 56, 623) as well as the jackknife confidence interval by Dayton ( 2003 , Br. J. Math. Stat. Psychol., 56, 1) perform poorly, and propose a new bias-corrected point estimate, a bootstrap test and confidence limits for pi-star. The proposed confidence limits have coverage probability much closer to the nominal level than the other methods do. We illustrate the usefulness of the proposed method in practice by presenting some practical applications to log-linear models for contingency tables.  相似文献   

3.
The high-entropy Ti–Zr–V–Cr–Ni (20 at% each) alloy consisting of all five hydride-forming elements was successfully synthesised by the conventional melting and casting as well as by the melt-spinning technique. The as-cast alloy consists entirely of the micron size hexagonal Laves Phase of C14 type; whereas, the melt-spun ribbon exhibits the evolution of nanocrystalline Laves phase. There was no evidence of any amorphous or any other metastable phases in the present processing condition. This is the first report of synthesising a single phase of high-entropy complex intermetallic compound in the equiatomic quinary alloy system. The detailed characterisation by X-ray diffraction, scanning and transmission electron microscopy and energy-dispersive X-ray spectroscopy confirmed the existence of a single-phase multi-component hexagonal C14-type Laves phase in all the as-cast, melt-spun and annealed alloys. The lattice parameter a = 5.08 Å and c = 8.41 Å was determined from the annealed material (annealing at 1173 K). The thermodynamic calculations following the Miedema’s approach support the stability of the high-entropy multi-component Laves phase compared to that of the solid solution or glassy phases. The high hardness value (8.92 GPa at 25 g load) has been observed in nanocrystalline high-entropy alloy ribbon without any cracking. It implies that high-yield strength (~3.00 GPa) and the reasonable fracture toughness can be achieved in this high-entropy material.  相似文献   

4.
The addition of Ag to the age hardenable Mg–Gd–Zr alloy system dramatically enhances early stage age hardening kinetics. Using atom probe tomography (APT), Ag-rich clusters were detected in a Ag-containing Mg–Gd–Zr alloy immediately after solution treatment and water quenching. During subsequent isothermal ageing at 200 °C, a high density of basal precipitates was observed during the early stages of ageing. These basal precipitates were enriched with Ag and Gd, as confirmed by APT. It is posited that Ag-rich clusters in the context of quenched-in vacancies can attract Gd atoms, increasing diffusion kinetics to facilitate the formation of the Ag + Gd-rich basal precipitates. The rapid formation of Ag + Gd-rich precipitates was responsible for accelerated ageing.  相似文献   

5.
6.
《New Ideas in Psychology》2001,19(2):145-168
It is posited that there are three essential elements associated with human nature and the human personality: Animation, Accommodation, and Authorization (A3). These broadly construed elements are defined, and then it is shown how they underlie the ways humans cognitively and emotionally engage their world. This explication is made possible by calling on a novel construction, called a “trialogue”, that formally relates attributes of cognitive engagement (termed intellect) and attributes of emotional engagement to the three essential elements. The trialogue construction constrains the interrelationships among attributes and essential elements, enabling the internal validity of the theory to be tested. A preliminary study with 174 participants investigated the question of internal validity and found convincing evidence to support the basic premise of the model. The structural complementarities of intellect and emotional engagement may provide a better understanding not only of personality but also of some institutions (e.g., educational).  相似文献   

7.
Chris Fields 《Axiomathes》2014,24(1):137-156
The Ollivier–Poulin–Zurek definition of objectivity provides a philosophical basis for the environment as witness formulation of decoherence theory and hence for quantum Darwinism. It is shown that no account of the reference of the key terms in this definition can be given that does not render the definition inapplicable within quantum theory. It is argued that this is not the fault of the language used, but of the assumption that the laws of physics are independent of Hilbert-space decomposition. All evidence suggests that this latter assumption is true. If it is, decoherence cannot explain the emergence of classicality.  相似文献   

8.
Ferroelectric (FE) materials directly convert electrical energy to mechanical energy and are critical to applications such as sensors, transducers, and actuators. The giant electromechanical response is the manifestation of the critical point between the first-order and second-order ferroelectric–paraelectric (FE–PE) transitions. For the simple classic FE lead titanate (PbTiO3), it is commonly accepted that there is a critical point in the temperature–pressure phase diagram separating the first- and second-order FE–PE transitions at zero electric field. Here, we show that the FE-PE transition in PbTiO3 is second-order at zero electric field. We introduce the concept of the invariant critical points (ICP) among three phases, representing the stability of the PE phase with respect to two FE phases in a three-dimensional electric field-pressure-temperature phase diagram of PbTiO3. It is pointed out that the electromechanical response near ICPs is larger than that near the line of critical end points (LCEPs) between two phases.  相似文献   

9.
The effect of ultrafine-grained structure formation in Mg–Zn–Zr alloy ZK60 on its mechanical response was investigated at strain rates ranging from quasi-static to dynamic regimes. The study demonstrated that the strength characteristics of the material rise significantly with increasing strain rate, while its ductility is reduced. These effects are particularly pronounced in the dynamic loading regime, at strain rates in the (1?5)?×?102?s?1 range. In the ultrafine-grained alloy ZK60, the energy absorption per unit volume, W, is enhanced by grain refinement by a factor as high as eight for the highest strain rate of 5?×?102?s?1 investigated. The analysis is focused on the microstructure features that bring about the observed improvement of the tensile characteristics, as well as the deformation and fracture modes prevalent at different strain rates. The results obtained contribute to the exploration and understanding of dynamic behaviour of magnesium alloys.  相似文献   

10.
Over the course of psychology’s first several decades, the language used to convey the subject matter gradually shifted from being free and literary to being strictly constrained and disciplined by increasingly focused theoretical demands. The project described here, “Disciplining Psychology,” aimed to depict this transformation by generating images of the faces of three highly influential psychologists—William James, Sigmund Freud, and B. F. Skinner. Each image is composed of the words used in one of each individual’s most important books. The tightening of the disciplinary vocabulary is revealed in the differences among the three arrays of words themselves, but I have also striven to reflect it in the aesthetic aspects of each image. The method used here could easily be extended to a wider array of authors, texts, and psychological topics.  相似文献   

11.
We examined the factor structure of the Neuroticism scale of the Eysenck Personality Questionnaire (EPQ–R–N; S. B. G. Eysenck, Eysenck & Barrett, 1985) and its factor invariance across sex and racial/ethnic groups in a sample of 1,979 adolescents. Using confirmatory factor analyses, we compared a hierarchical model to previous models of the EPQ–R–N and to single-factor and 3-factor structures. The hierarchical factor structure in which a general factor coexists with 3 group factors (depression, social concerns, and worry) was superior to alternative models. The general factor accounted for more than 60% of the variance in EPQ–R–N total scores and was invariant across sex and ethnicity. The 3 group factors varied across ethnicity and sex. We discuss the implications of these findings for conceptualization and assessment of neuroticism using the EPQ–R–N.  相似文献   

12.
The kinetics for the termination migration of a rod-type alpha particle in a two-phase Ti alloy was predicted on the basis of the edge recession theory. The developed model quantified the effect of geometrical dimensions and diffusional factors on the spheroidization rate. Comparison with the experimental results of Ti–6Al–4Fe showed that the model can provide a reasonable prediction of the time to complete the static spheroidization of rod-type particles.  相似文献   

13.
A new suicide-specific diagnostic entity, acute suicidal affective disturbance (ASAD), was recently proposed to fill a void in the nomenclature. Although several studies have examined the reliability, validity, and potential clinical utility of ASAD, no studies have examined personality indicators of ASAD. This study sought to examine the association between personality and psychopathology factors, as assessed by the Minnesota Multiphasic Personality Inventory–2–Revised Form (MMPI–2–RF), and constructs that comprise ASAD in a sample of 554 psychiatric outpatients who completed all measures prior to their intake appointments. A smaller subset of patients (N = 58) also completed a measure designed to assess lifetime ASAD symptoms. Results indicated that ASAD symptoms were associated with traits characterized by emotional turmoil and atypical cognitive processes. Further, suicide-related criteria that comprise ASAD were related to low positive emotionality and hopelessness, whereas the overarousal criteria were associated with somatic symptoms and an inability to tolerate frustration and stress. These findings expand on previous research that examines the convergent and discriminant validity of ASAD and could inform clinical treatment by providing insight into personality traits that might be associated with acute suicide risk.  相似文献   

14.
Following a period of decline beginning in the early eighteenth century, the Orthodox Church in Russia held a general council in Moscow from August 1917 to September 1918. More than 500 clergy and laity met, prayed and discussed numerous issues relating to the church’s life and witness. The Moscow Council was prompted by various trends of renewal which were growing ever stronger among the clergy and laity. Political circumstances at the time also made the Council possible: a preparatory preconciliar process was initiated in 1905, in parallel with the first revolution against Emperor Nicholas II, and the Council itself was convened in 1917, in parallel with the establishment of a Provisional Government. However, it was precisely such political events which led to the premature interruption of the Council. The main items on the Council’s agenda were linked to the reformation of church structures and the implementation of conciliar provisions at every level of church life: parish, deanery, diocese and autocephalous church. Special attention was given to the renewal of the pastoral ministries of priests and bishops, and to that of committed laity. In a way, the Moscow Council was a kind of ‘first encounter’ of Orthodoxy with contemporary societies, secularised or on the road to secularisation. Its legacy is therefore of great interest to all Christianity today. This article aims to analyse the Council and the main decisions made, in the light of ecclesiology, and to provide a primary bibliography at the end of the text.  相似文献   

15.
The formation and stability of the quasicrystalline icosahedral (i) phase in melt-spun Al93– x Fe3Cr2Ti2Si x (x?=?0–5) ribbons are reported. Samples were characterized by X-ray diffraction, differential scanning calorimetry and transmission electron microscopy. Primitive (P-type) ordered i phase particles were found to be homogeneously distributed in an fcc α-Al matrix in the as-melt-spun ribbons. The size of the i phase particles decreased and their thermal stability increased with increasing substitution of Al by Si. The i phase had a decomposition temperature of approximately 480°C in an Al93Fe3Cr2Ti2 ribbon whereas that in an Al92Fe3Cr2Ti2Si1 ribbon was approximately 500°C. The i phase particles are resistant to coarsening prior to decomposition into crystalline phases. The presence of a small quantity of Si (up to 1.0?at.%) is beneficial to both the thermal stability and the hardness of nanoquasicrystalline Al–Fe–Cr–Ti alloys.  相似文献   

16.
Skrzypulec  Błażej 《Synthese》2021,198(3):2101-2127
Synthese - It is commonly believed that human perceptual experiences can be, and usually are, multimodal. What is more, a stronger thesis is often proposed that some perceptual multimodal...  相似文献   

17.
When switching tasks, performance tends to be worse for n – 2 repetitions than with n – 2 switches. This n – 2 repetition cost has been hypothesized to reflect task-set inhibition: specifically, inhibition of irrelevant category–response mappings involved in response selection. This hypothesis leads to divergent predictions for situations in which all tasks involve the same stimulus categories: An n – 2 repetition cost is predicted when response sets differ across tasks, but not when the response set stays the same. The authors tested these predictions by having subjects perform relative judgements with different reference points. In Experiment 1, the stimulus categories were the same across reference points, but the response set either differed or stayed the same (the multiple- and single-mapping conditions, respectively). An n – 2 repetition cost was found in the multiple-mapping condition but not in the single-mapping condition. Experiment 2 provided evidence against the possibility that these divergent effects reflected differences in memory load. These findings confirm predictions that link n – 2 repetition costs to inhibition of irrelevant category–response mappings.  相似文献   

18.
The purpose of this article is to present an approach to defining, identifying, and assessing personality disorders, including the links between these definitions and personality assessment, with a particular reference to the proposed revisions to the personality disorders section of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (5th ed. [DSM–5]; American Psychiatric Association, 2013 American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Washington, DC: Routledge.[Crossref] [Google Scholar]). The article discusses measures of maladaptive variants of the Five-factor model (FFM) that are coordinated with both the traditional personality disorder syndromes as well as the DSM–5 dimensional trait model. Discussed as well is the assessment of the more psychodynamically oriented deficits in sense of self and interpersonal relatedness that are also included within the hybrid model proposed for DSM–5.  相似文献   

19.
20.
This paper outlines and defends a notion of tragic-remorse. This moral emotion properly accompanies those actions that involve unavoidable moral wrongdoing in general and dirty hands scenarios in particular. Tragic-remorse differs both phenomenologically and conceptually from regret, agent-regret and remorse. By recognising the existence of tragic-remorse, we are better able to account for our complex moral reality which at times makes it necessary for good persons to act in ways that although justified leave the agent with a moral stain and a particular emotional response.  相似文献   

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