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1.
Precise X-ray diffraction measurements have revealed that phonon (conventional) strain is introduced at the phase transition from an icosahedral quasicrystal to its orthorhombic crystal approximant in a Mg–Ga–Al–Zn alloy. From the magnitude of the measured phonon strain, the phonon–phason coupling constant has been evaluated. This constant is approximately ?0.03μ (μ: shear modulus) and it is in good agreement with the result of a theoretical calculation reported previously (W.-J. Zhu and C.L. Henley, Europhys. Lett. 46 748 (1999)). This is the first study that experimentally evaluates the phonon–phason coupling constant in any existing quasicrystalline phase.  相似文献   

2.
Plate-shaped Guinier–Preston (G–P) zone formation in an Al–Zn–Mg–Cu–Zr alloy has been studied using transmission electron microscopy. The results provide, for the first time, direct evidence showing nucleation and growth of plate-shaped coherent G–P zones during natural aging.  相似文献   

3.
A liquid quinary alloy with composition Ni–5%Cu–5%Fe–5%Sn–5%Ge has been prepared from a containerless state by undercooling. Dendritic growth of α-Ni phase took place with a velocity of 28 m s?1 at the maximum degree of undercooling, which was as high as 405 K (0.24T L). All of the four solute elements Cu, Fe, Sn and Ge exhibited a significant solute trapping effect during the rapid dendrite growth. Segregation-less solidification is consequently realized when the degree of undercooling is sufficiently large. The lattice constant of α-Ni solid solution phase is found to increase with the amount of multicomponent solute trapping.  相似文献   

4.
The recrystallization behaviour of a cold-rolled, low-density, low-alloy duplex-phase alloy (Fe–6.57Al–3.34Mn–0.18C, wt.%) has been studied. Temperature-resolved X-ray diffraction and dilatometry showed that the alloy recrystallizes at 850?°C during continuous heating. However, electron back-scattered diffraction investigations using Kernel average misorientation revealed that during annealing ferrite recrystallizes at lower temperatures while austenite remains strained up to 1200?°C. This study underlines the complexity of recrystallization of a microstructure comprising of constituents with high and low stacking fault energy.  相似文献   

5.
In this report, coparenting behaviors during triangular interactions among families raising a 3-month-old infant in Turkey are examined. Given the significant role played by extended family members in Turkish culture, coparenting dynamics were examined as mothers and babies played together with grandmothers, as well as together with fathers. Forty-five families took part, and 42 father–mother–baby and 33 grandmother–mother–baby triangular interactions of approximately 10?min in length were filmed during the Lausanne Trilogue Play. From videotapes of the interactions, individual and mutual coparenting behaviors were evaluated using the Coparenting and Family Rating System: 3 Month Adaptation (CFRS3M). Results indicated that while mothers’ own parenting behavior when in the LTP role of Active Parent (AP) was comparable whether with fathers or grandmothers, their behavior when in the LTP role of third party parent (TPP) was comparatively more engaged while with fathers than while with grandmothers. Fathers were comparatively less engaged when occupying the TPP role than were mothers in the TPP role, while grandmothers showed more flirting and distracting behavior in the TPP role than did either fathers or mothers. These findings are significant in documenting meaningful distinctions in Turkish grandmothers’ as well as in Turkish fathers’ and mothers’ coparenting propensities when engaging in triangular interactions with babies during the LTP.  相似文献   

6.
ABSTRACT

Few bibliographies exist that specifically focus on the resources available for lesbian and gay people of faith. This paper seeks to gather some of the best resources, both old and new, into a cohesive and comprehensive format as they mainly relate to the Christian tradition. Focusing on available books, as well as Internet resources, annotated lists have been assembled that document resources that many theological libraries might consider for purchase. Books have been categorized in typical library categories and each entry is annotated to aid in selection. Internet sites have also been annotated to explain their inclusion in the article.  相似文献   

7.
We obtain a phase diagram for a trapped two-dimensional ultracold Bose gas. We find a critical temperature above which the free energy of a state with a pair of vortices of opposite circulation is lower than that for a vortex-free Bose–Einstein condensed ground state. We identify three distinct phases which are, in order of increasing temperature, a phase coherent Bose–Einstein condensate, a vortex pair plasma with a fluctuating condensate phase, and a thermal Bose gas. The existence of the vortex pair phase could be verified using current experimental set-ups.  相似文献   

8.
The conceptual projection of time onto the domain of space constitutes one of the most challenging issues in the cognitive embodied theories. In Chinese, spatial order (e.g., “大树前”/da shu qian/, in front of a tree) shares the same terms with temporal sequence (三月前”, /san yue qian/, before March). In comparison, English natives use different sets of prepositions to describe spatial and temporal relationship, i.e., “before” to express temporal sequencing and “in front of” to express spatial order. The linguistic variations regarding the specific lexical encodings indicate that some flexibility might be available in how space–time parallelisms are formulated across different languages. In the present study, ERP (Event-related potentials) data were collected when Chinese–English bilinguals processed temporal ordering and spatial sequencing in both their first language (L1) Chinese (Experiment 1) and the second language (L2) English (Experiment 2). It was found that, despite the different lexical encodings, early sensorimotor simulation plays a role in temporal sequencing processing in both L1 Chinese and L2 English. The findings well support the embodied theory that conceptual knowledge is grounded in sensory-motor systems (Gallese and Lakoff, Cogn Neuropsychol 22:455–479, 2005). Additionally, in both languages, neural representations during comprehending temporal sequencing and spatial ordering are different. The time–spatial relationship is asymmetric, in that space schema could be imported into temporal sequence processing but not vice versa. These findings support the weak view of the Metaphoric Mapping Theory.  相似文献   

9.
Marvin Skolnick 《Group》2000,24(2-3):133-145
Much has been learned in the 20th century about the impact of covert group dynamics on the individual, the family and small group on the micro level and about institutions, communities, national and international process on a macro level. However, as we enter the new millennium this knowledge seems dwarfed by the burgeoning of knowledge about the brain and biological approaches to disturbed human behavior, casting a worrisome shadow on the future of dynamic group therapies. This article explores the impact of socio-economic-political forces on mental health delivery systems from the vantage point of group process and therapy, and raises questions about possible interventions to restore a balance between social dynamics and biology.  相似文献   

10.
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   

11.
A Zr62Cu15.5Al10Ni12.5 bulk metallic glass with a large supercooled liquid region of 90 K, produced by copper-mould casting, exhibits a high strength of 1730 MPa and superior but highly inhomogeneous plasticity under uniaxial compression at ambient temperature. Micro-X-ray diffraction shows that compressive loading facilitates crystallization in the monolithic glassy alloy, resulting in room-temperature plasticity. The plastic deformation of the Zr62Cu15.5Al10Ni12.5 BMG may be attributed to in situ precipitation of nanocrystals during compression in heavily deformed areas.  相似文献   

12.
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   

13.
This article describes the development, internal psychometric, and external validation studies on scales designed to measure the Personality Psychopathology Five (PSY–5) from MMPI–2 Restructured Form (MMPI–2–RF) items. Diverse and comprehensive data sets, representing various clinical and nonclinical populations, were classified into development and validation research samples. Item selection, retention, and exclusion procedures are detailed. The final set of PSY–5–RF scales contain 104 items, with no item overlap between scales (same as the original MMPI–2 PSY–5 scales), and no item overlap with the Demoralization scale. Internal consistency estimates are comparable to the longer MMPI–2 PSY–5 scales. Appropriate convergent and discriminant validity findings utilizing various self-report, collateral rating, and record review data are reported and discussed. A particular emphasis is offered for the unique aspects of the PSY–5 model: psychoticism and disconstraint. The findings are connected to the broader PSY–5 literature and the recommended review of systems (Harkness, Reynolds, & Lilienfeld, this issue) presented in this series of articles.  相似文献   

14.
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   

15.
《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   

16.

Other Index

Cumulative Index 1978–2002 (Volumes 1–25)  相似文献   

17.
Cover 4–TOC     
《Brain and language》2006,96(3):CO4
  相似文献   

18.
19.

Other Index

Cumulative Index Volumes 39–48 (1996–2000)  相似文献   

20.
When talking about automation, “autonomous vehicles”, often abbreviated as AVs, come to mind. In transitioning from the “driver” mode to the different automation levels, there is an inevitable need for modeling driving behavior. This often happens through data collection from experiments and studies, but also information extraction, a key step in behavioral modeling. Particularly, naturalistic driving studies and field operational trials are used to collect meaningful data on drivers’ interactions in real–world conditions. On the other hand, information extraction methods allow to predict or mimic driving behavior, by using a set of statistical learning methods. In simple words, the way to understand drivers’ needs and wants in the era of automation can be represented in a data–information cycle, starting from data collection, and ending with information extraction. To develop this cycle, this research reviews studies with keywords “data collection”, “information extraction”, “AVs”, while keeping the focus on driving behavior. The resulting review led to a screening of about 161 papers, out of which about 30 were selected for a detailed analysis. The analysis included an investigation of the methods and equipment used for data collection, the features collected, the size and frequency of the data along with the main problems associated with the different sensory equipment; the studies also looked at the models used to extract information, including various statistical techniques used in AV studies. This paved the way to the development of a framework for data analytics and fusion, allowing the use of highly heterogeneous data to reach the defined objectives; for this paper, the example of impacts of AVs on a network level and AV acceptance is given. The authors suggest that such a framework could be extended and transferred across the various transportation sectors.  相似文献   

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