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11.

During the course of investigation of the phase equilibria in the Nb-Ti-Al system, a new phase, designated theta, was observed in three Nb-Ti-40at.%Al alloys following ageing at low temperatures (less than 1000 C). Using X-ray diffraction and transmission electron microscopy techniques, this phase was determined to have a bct structure, with lattice parameters a0 = 5.106 A and c0 = 28.168A, a space group of I 41/amd (number 141) and composition near 45at.%Nb25at.%Ti-30at.%Al. An orientation relationship between the new tetragonal phase and the gamma-TiAl phase of [101]gamma//[120]theta and (111)gamma//(001)theta was observed within the microstructure.  相似文献   
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Stacking fault tetrahedra (SFTs) are known to form during the rolling process of face-centered cubic metals and to deteriorate their structural properties. However, the atomistic mechanism of formation and destruction of SFTs during such material processing is still unclear. We have performed molecular dynamics simulations of the nanoscale cryo-rolling process for single-crystal nickel and here report the mechanism behind the formation and collapse of SFTs. It is found that SFTs are formed through dissociation of Shockley partial dislocation loops in the specimen. On the other hand, destruction of SFTs occurs under compressive stress and follows an inverse Silcox-Hirsch mechanism.  相似文献   
14.
This paper investigates and explores the link between the resilience of organisations, its human capital and firm performance. We base our analysis on the resource-based view of the firm, cluster strategy, and conservation of resources theories. Our contribution is contextualised by comparing the performance of business clusters across two observational periods, namely pre-recession (2005–2007) and recession (2008–2009) period. We identify six relevant indicators from the extant literature that capture economic dynamism, human capital, and financial viability of firms in order to capture the performance across clusters and capture resilience to the global financial crisis. We contribute by identifying organisations in business clusters that perform better due to being more resilient, particularly during challenging times. Through triangulation we find overwhelming evidence of the overarching role and importance of human capital (people) in driving more successful organisations in business clusters as they possess greater resilience during challenging times such as the recent global financial crises. We show that strong clusters not only improve regional employment and turnover growth over time, but improve resilience of regional economies to downturns through resource gain and crossover processes. We further illustrate that understanding the impact of resource reservoirs, resource passageways and crossover provides a framework for further research and intervention to promote resilience in organisations.  相似文献   
15.
The paper describes use of trade‐off information to create effective stock portfolio characterized by desired values of selected stock attributes. Basic notions behind such portfolio creation processes are discussed and related to the multiattribute analysis performed by evaluating compensations among the attributes’ values. A framework to construct a portfolio using only compensatory information is presented and applied to the analysis of the stocks traded on the Toronto Stock Exchange. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
16.
There is a growing need to understand the global impact of poverty on early brain and behavioural development, particularly with regard to key cognitive processes that emerge in early development. Although the impact of adversity on brain development can trap children in an intergenerational cycle of poverty, the massive potential for brain plasticity is also a source of hope: reliable, accessible, culturally agnostic methods to assess early brain development in low resource settings might be used to measure the impact of early adversity, identify infants for timely intervention and guide the development and monitor the effectiveness of early interventions. Visual working memory (VWM) is an early marker of cognitive capacity that has been assessed reliably in early infancy and is predictive of later academic achievement in Western countries. Here, we localized the functional brain networks that underlie VWM in early development in rural India using a portable neuroimaging system, and we assessed the impact of adversity on these brain networks. We recorded functional brain activity as young children aged 4–48 months performed a VWM task. Brain imaging results revealed localized activation in the frontal cortex, replicating findings from a Midwestern US sample. Critically, children from families with low maternal education and income showed weaker brain activity and poorer distractor suppression in canonical working memory areas in the left frontal cortex. Implications of this work are far‐reaching: it is now cost‐effective to localize functional brain networks in early development in low‐resource settings, paving the way for novel intervention and assessment methods.  相似文献   
17.
Some theorists have argued that the immediate recency effect observed in free recall reflects the emptying out of the contents of a short-term memory buffer (Davelaar, Goshen-Gottstein, Ashkenazi, Haarmann, & Usher, 2005). Others have argued that immediate recency reflects the properties of temporal context used to cue free recall (Howard & Kahana, 2002). We examined immediate free recall of lists with an item from the middle of the list repeated at or near the end. If associative processes contribute to immediate recency, as predicted by the temporal context account, the neighbors of the initial presentation of the repeated item should show enhanced recall at the initial stages of immediate recall. Recall transitions early in output--and even the initiation of recall itself-showed evidence for temporally defined associations that resemble those observed in recall from long-term memory. These results have strong implications for models of the immediate recency effect in free recall.  相似文献   
18.
The link between movement abnormalities and psychotic disorders is presumed to reflect common neural mechanisms that influence both motor functions and vulnerability to psychosis. The prodromal period leading to psychotic disorders represents both a viable point for intervention and a developmental period that, if studied, could shed light on etiology; however, no published studies have examined the temporal progression of this link. A group with high levels of prodromal symptomatology (i.e., adolescents with schizotypal personality disorder [SPD]; n = 42) and both psychiatric controls (with other personality disorders or conduct disorder [OD]; n = 30) and nonpsychiatric controls ([NC]; n = 49) were recruited. Videotapes of structured psychiatric interviews were coded for movement abnormalities by raters blind to participants' diagnostic status, and follow-up assessments were conducted 1 year later. Controlling for psychotropic medications, the authors found that adolescents with SPD exhibited significantly more motor abnormalities in the face and upper body than did OD and NC controls. At baseline, movement abnormalities were positively correlated with the severity of positive, negative, and total prodromal symptoms. Within the SPD group, baseline movement abnormalities predicted symptom severity 1 year later. Movement abnormalities represent an early risk indicator that may be predictive of later symptom severity and potentially of psychosis onset.  相似文献   
19.
Few cross-national studies have been conducted on academic dishonesty. The aim of this study was to explore students’ disclosed levels of academic dishonesty between New Zealand and Nigeria. The measures obtained included incidence, acceptability, and justification of dishonest action. It was hypothesized that there would be differences between the two groups and that differences could be explained in terms of deontology, cultural relativism, utilitarianism, rational fair exchange, and/or response bias. There were 844 medical and health science students who participated in the study and completed a questionnaire that explored incidence, acceptability, and justification of dishonest action. A binary logistic regression revealed that age and incidence were significant predictors of country allocation. Nigerian students reported more engagement in dishonest behaviors, and it is argued that these students have diverse cultural expectations, language variances, response strategies, norms, beliefs, and values. Educational interventions are essential to address concerns related to academic dishonesty such as promoting cross-cultural discourse, providing study skills programs, utilizing peer mentoring, creating formal exchange strategies, and endorsing honor codes.  相似文献   
20.
International Journal of Hindu Studies - This article focuses on the writings of the lonely, orphaned poet Janābāī, a popular figure believed to have lived in fourteenth-century...  相似文献   
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