Characterisation of magnesium oxide and its interface with α-Mg in Mg–Al-based alloys

Magnesium oxide (MgO) films and particles have been collected by pressurised filtration of a Mg-8.6wt%Al-0.67wt%Zn (AZ91D) alloy melt. The morphology of the oxides and their interfaces with the α-Mg phase were investigated by high-resolution transmission electron microscopy. It was found that the oxide films consisted of large numbers of sub-micrometre-sized MgO particles, and that melt shearing can effectively break up the oxide films and disperse the oxide particles. For the first time, orientation relationships (ORs) of OR I: [1?1?1]_MgO～2° from (0?0?0?1)_α-Mg and (0?1?1)_MgO?//[2?1?1?0)_α-Mg; and OR II: (1?1?1)_MgO//(1?1?0?1)_α-Mg and [0?1?1]_MgO//[1?2?1?1]_α-Mg, were observed between the MgO particles and the α-Mg matrix. The calculated Bramfitt planar disregistries were 5.5% and 2.5% for the two ORs, respectively, indicating good lattice matching between MgO and α-Mg at the interface. With the evidence of grain refinement effect observed in the sheared AZ91D magnesium alloy, the possibility of MgO particles to act as potent nucleants for heterogeneous nucleation of α-Mg grains is discussed in terms of the crystallographic criterion.     

TEM observation of oxide scale formed on a Ti–Al–Zr alloy oxidized at 360°C in alkaline steam

Ti–Al–Zr alloy has been oxidized at 360°C in alkaline steam at a pressure of 10.3?±?0.7?MPa. Cross-sectional transmission electron microscopy (TEM) observations indicated that the oxide scale of Ti–Al–Zr alloy was composed of outer and inner subscales, in which the outer layer consists of anatase-TiO₂ and the inner layer a mixture of TiO and Ti₂O. The thickness of the Ti₂O, TiO and anatase-TiO₂ were approximately 50, 100 and 400?nm, respectively. These results were confirmed by X-ray energy dispersive spectrometry (EDS) measurements. The enhanced corrosion of titanium alloys in LiOH solution is attributed to a high hexagonal Ti₂O to tetragonal TiO₂ phase transformation rate induced by the substitution of Li⁺ for Ti⁴⁺ in the oxide layer.     

Effect of aspect ratio on the compressive deformation and fracture behaviour of Zr-based bulk metallic glass

The compressive deformation and fracture features of Zr₅₉Cu₂₀Al₁₀Ni₈Ti₃ bulk metallic glassy samples with aspect ratios in the range of 0.67–2.00 have been investigated. The compressive plastic strain of the glass monotonically increases with decreasing aspect ratio, but the maximum strength almost maintains a constant value of 1.77–1.88?GPa. All the compressive shear-band angles are equal to?～40° if modified by the rotation of the primary shear bands.     

Wear behaviour of a gradient surface produced by a punching process in a Cu-30 Ni alloy

The grain size variation in a gradient surface produced by a punching and recovery process on a Cu-30Ni alloy has been observed by atomic force microscopy. The friction characteristics of the gradient surface in a 3.5 wt% NaCl solution were investigated using a micro-indenter probe, a pin-on-disc type tribometer, a strain sensor and an optical microscope. The results showed that the hardness and grain size can be well represented by the Hall–Petch relationship when the gain size is more than 30?nm. The wear rate, friction coefficient and adhesive force all increase depth below the surface. These variations are attributed to a gradual increasing grain size with depth. The morphologies of the worn track were also studied to understand further the corrosive wear behaviour of gradient surfaces.     

Short-term memory and working memory as indices of children's cognitive skills

In the current literature, empirical and conceptual distinctions have been drawn between a more or less passive short-term memory (STM) system and a more dynamic working memory (WM) system. Distinct tasks have been developed to measure their capacity and research has generally shown that, for adults, WM, and not STM, is a reliable predictor of general cognitive ability. However, the locus of the differences between the tasks has received little attention. We present data from children concerning measures of matrices reasoning ability, reading, and numerical skill along with forward and backward order serial recall of WM, STM, and STM with articulatory suppression tasks. As indices of children's cognitive skills, STM and WM are shown to be rather similar in terms of memory per se. Neither the opportunity for rehearsal nor task complexity provides satisfactory explanations for differences between memory tests.     

Direct Comparison of Episodic Encoding and Retrieval of Words: An Event-related fMRI Study

Functional magnetic resonance imaging (fMRI) was used to compare directly episodic encoding and retrieval. During encoding, subjects studied visually presented words and reported via keypress whether each word represented a pleasant or unpleasant concept (intentional, deep encoding). During the retrieval phase, subjects indicated (via keypress) whether visually presented words had previously been studied. No reliable differences were found during the recognition phase for words that had been previously studied and those that had not been studied. Areas preferentially active during encoding (relative to retrieval) included left superior frontal cortex, medial frontal cortex, left superior temporal cortex, posterior cingulate, left parahippocampal gyrus, and left inferior frontal gyrus. Regions more active in retrieval than encoding included bilateral inferior parietal cortex, bilateral precuneus, right frontal polar cortex, right dorsolateral prefrontal cortex, and right inferior frontal/insular cortex.     

Mother‐child relationships and creativity

The present study focused on the relationship between young children's level of differentiation and creative potential as assessed by the Torrance Tests of Creative Thinking (TTCT). The mothers of high and low creative children were interviewed in order to establish the degree to which they encouraged differentiation in their children. Their level of involvement with their children was also evaluated using the Family Relations Test (FRT). Mothers of high creative children were less emotionally involved with their children than other mothers, less likely to be perceived as overprotective, and less likely to deny their feelings of hostility towards them. They were more self‐confident and self‐realized in their homes and had higher occupational levels than other mothers. The present study also assessed the level of differentiation in both creative and uncreative children with the Draw‐a‐Person and Kinetic Family Drawing Tests. Results indicated that highly creative children were more differentiated than uncreative children.     

Personality determinants of the commitment to the profession of art

The model of commitment presented in the present report postulates personality to be the crucial element in the development and maintenance of commitment to the profession of art. The objectives of the research reported here were to (a) demonstrate the typicality of the artist personality and (b) identify the traits which characterize committed and uncommitted artists. Three groups of artists were compared: mature established artists described as committed over a lifetime, committed art students, and uncommitted art students. The instrument used to evaluate personality was the Adjective Check List (ACL; Gough 8c Heilbrun, 1983). Both committed and uncommitted artists presented a typical personality structure; but in contrast to the committed, the uncommitted were characterized by low self‐esteem, a negative self‐image, impaired motivation, low staying power, and an inability to find a clear direction. Both art students and mature artists agreed about the order of importance of 11 factors considered to be determinants of committment. They both placed particular emphasis on autonomy, possibility to experiment, ease of inspiration, and early identification with the profession.     

Discussion: Toward a social‐constructivist view of the psychoanalytic situation

The three papers by Modell, Aron, and Greenberg are discussed in terms of their relationship to a new paradigm for understanding the psychoanalytic situation. The paradigm is called social‐construct‐ivist to capture both the idea of the analyst's participation and the idea of construction of meaning. It is argued that these theorists, as well as many of the authors they cite as part of a broad movement in the field, do not consistently meet the criteria for this paradigm, although they seem to be aiming for it. An important source of inconsistency and confusion derives from the confounding of the two axes: drive‐relational and positivist‐constructivist. Many relational theorists who hold fast to the idea that analysts can grasp the truth of both their own experience and that of the patient are no closer to the constructivist point of view than was Freud. The call by Aron and Greenberg for greater attention to the patient's resisted experience of the analyst's subjectivity is discussed in terms of its potential benefits and problems. The ritualized asymmetry of the psychoanalytic situation is said to have important functions, including prevention of excessive involvement and protection of the unobjectionable positive transference and of a degree of idealization. Modell's notion of paradox, which makes the therapeutic relationship seem “real”; and “unreal”; at the same time, is seen as a special instance of the always precarious social construction of reality. It is argued, moreover, that the social and individual aspects of experience are interdependent. Neither is reducible to the other, and both should be understood, like many other issues in the new paradigm, in terms of a dialectical interplay of figure and ground in experience.