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51.
This article describes the influence of microstructure on the dielectric and piezoelectric properties of isovalent- donor- and acceptor-modified lead lanthanum zirconium titanate (PLZT) ceramics. The ceramic compositions, with formula: [Pb0.954La0.016Ba0.01Sr0.02][Zr0.525Ti0.475]0.981?( m /2)Nb0.012Zn m O3 where m =?0, 0.2, 0.4, 0.6, 0.8 and 1.0 mol% Zn, were synthesized via a solid-state reaction method. X-ray diffraction studies are supported by tolerance factor and electronegativity difference measurements. Scanning electron microscopy studies reveal grain growth enhancement with increase of Zn concentration. As the Zn concentration increased from 0 to 0.8 mol%, the room-temperature dielectric constant increased while the Curie temperature decreased continuously. An increase in the Zn content had the most significant effect on the piezoelectric properties. The optimum piezoelectric properties were observed for 1 mol% Zn composition.  相似文献   
52.
Carbon nanotubes have been intensively studied owing to their great potential in nanoelectronics and nanomechanical devices. Recently, experimental results have shown that single-walled carbon nanotubes (SWCNTs) change their electronic properties when subjected to strain. In this study, the electromechanical characteristics of SWCNT networks were investigated for the application of printable strain sensors on flexible substrates. SWCNT films were formed on plastic substrates of poly(ethylene terephthalate) using a spray process. In this manner, we were able to control the transparency and obtain uniform electrical properties of the films. The films are isotropic on account of the random orientation of bundles of SWCNTs. Experimental results showed a nearly linear change in the resistance across a film when it was subjected to tensile strain, even in the inelastic range of the flexible substrate. The results demonstrate the potential use of SWCNT films for highly sensitive printable strain sensors on a macroscale.  相似文献   
53.
This study aimed to develop and validate the General Psychological Well-being Scale (GPWS) in an African sample, based on the empirical overlap between hedonic and eudaimonic facets of well-being as found in previous research. The quantitative cross-sectional study was conducted in three phases: secondary data analysis (n = 2005), pilot study (n = 296) and main study (n = 459). The pilot and main study included the GPWS as well as other psychological well-being measures for criterion-related validity. The pilot study yielded satisfactory psychometric properties. The main study yielded a high, reliable Cronbach alpha of.89 and evidence of construct validity. The GPWS appears to be a unidimensional scale suitable for research use with Setswana-speaking people.  相似文献   
54.
This study reports the findings from exploratory career counselling with Italian undergraduate university students using the Career Interest Profile (CIP). The participants (n = 178, females = 51.69%; mean age 22.28, SD = 1.59 years) received elective career counselling on campus. The students completed the CIP and the Self-Directed Search (SDS). Data were analyzed using both qualitative and quantitative approaches. The CIP yielded satisfactory results with regard to trustworthiness and intercorrelations with the SDS and provides career counsellors with a useful instrument for the identification of interest profiles of Italian undergraduate university students. Participants reported being enabled to explore prospective career interest areas using career-story narratives for constructing life trajectories and enhanced development of their career stories.  相似文献   
55.
Observers can visually track multiple objects that move independently even if the scene containing the moving objects is rotated in a smooth way. Abrupt scene rotations yield tracking more difficult but not impossible. For nonrotated, stable dynamic displays, the strategy of looking at the targets' centroid has been shown to be of importance for visual tracking. But which factors determine successful visual tracking in a nonstable dynamic display? We report two eye tracking experiments that present evidence for centroid looking. Across abrupt viewpoint changes, gaze on the centroid is more stable than gaze on targets indicating a process of realigning targets as a group. Further, we show that the relative importance of centroid looking increases with object speed.  相似文献   
56.
Adventure based counselling is a short-term experiential psychotherapeutic approach, which utilises adventurous activities and being in natural environmental in order to facilitate therapeutic change in clients. The present paper critically appraises the results of a qualitative study that investigated how clients with self-reported anxiety and depression experienced participating in an innovative counselling intervention with combined individual counselling with such an adventurous outdoor transaction. Interpretative Phenomenological Analysis, as described by Smith and Osborn (2008), was used in order record and analyse the experiences of four male and six female students who were treated at the Teesside's University Counselling Service. Interviewees perceived the counselling sessions as offering a safe therapeutic space within which they could unveil their anxieties and achieve inner healing, whereas the outdoor transaction as providing an experiential venue for achieving personal change. Interviewees felt that without the outdoor transaction the therapeutic significance of the counselling process would not have reached its full potential. Likewise, without the individual counselling, the outdoor transaction would just have an entertaining event and not a venue for personal change. These findings are discussed in relation to object relations theory.  相似文献   
57.
This study explored the relationships between object representations of mother and father and recovery among outpatients with psychotic disorders, and examined the role of attachment to God in moderating those relationships. A total of 46 outpatients diagnosed with schizophrenia or schizoaffective disorder participated. Benevolent representations of mother and father were associated with recovery whereas punitive representations were negatively associated with recovery. Secure attachment to God amplified the association between benevolent representations of father and recovery. Secure attachment to God was found to buffer the relationship between mild-to-moderate punitive parental representations and recovery; however, this relationship was not evident for those with the most punitive parental representations. Directions for future research and clinical implications are discussed.  相似文献   
58.
The present study aimed at exploring the psychometric properties of the Test of Everyday Attention for Children (TEA-Ch) in normally developing Greek-speaking school population (6–12 years old). TEA-Ch is an assessment that captures the multidimensional nature of the developing attentional system with child-friendly test tasks. The sample consisted of 174 Greek-speaking primary school children of both genders (N = 88 girls). Children were assessed individually using the TEA-Ch and two tasks (Vocabulary and Working Memory) from the Wechsler Intelligence Scale for Children-3rd edition (WISC-III)-Greek Version. Confirmatory factor analyses were conducted to examine the factorial validity of the TEA-Ch in the Greek-speaking population. The results verified both a two-factor (attentional control/switching and sustained attention) and a theory-driven three-factor structure of the TEA-Ch, namely selective attention, attentional control/switching and sustained attention. Moreover, the weak correlations of TEA-Ch tasks with vocabulary and working memory tasks provide evidence for its divergent validity and its usefulness as an additional measure of abilities that are not captured by well-known conventional intelligence tasks. Furthermore, TEA-Ch appears to be an age-sensitive assessment tool.  相似文献   
59.
How accurate are explicit judgements about familiar forms of object motion, and how are they made? Participants judged the relations between force exerted in kicking a soccer ball and variables that define the trajectory of the ball: launch angle, maximum height attained, and maximum distance reached. Judgements tended to conform to a simple heuristic that judged force tends to increase as maximum height and maximum distance increase, with launch angle not being influential. Support was also found for the converse prediction, that judged maximum height and distance tend to increase as the amount of force described in the kick increases. The observed judgemental tendencies did not resemble the objective relations, in which force is a function of interactions between the trajectory variables. This adds to a body of research indicating that practical knowledge based on experiences of actions on objects is not available to the processes that generate judgements in higher cognition and that such judgements are generated by simple rules that do not capture the objective interactions between the physical variables.  相似文献   
60.
The author presents two sessions from the analysis of a depressive narcissistic doctor, which are characterised by a mixture of co-operation and pseudo-co-operation. The dialogue is in parts intellectualised, complicated, lifeless and schizoid. Points at which the patient shows surprising insights are then partly denigrated by him, on the basis that change is not to be expected. Semi-lifeless contact assists the defensive claustrophobia that he experiences in meaningful contact. It becomes very clear that he is then afraid of entering into an openly aggressive conflict that entails the existential threat of object loss. However, this has so far been avoided. The secret pleasure in an anal-narcissistic, sadomasochistic addiction to doubt persists in the partial denigration. The patient's artificially maintained self-doubt and doubt of the object reinforce a genuine confusion that consists in never knowing exactly what lies behind the helpful and needed object.  相似文献   
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