Cathodoluminescence-mode imaging of dislocations in zinc oxide

Abstract

The cathodoluminescence mode in the scanning electron microscope has been used to image bands of dislocations in zinc oxide. It has been shown that dislocations lying on pyramidal, {1012}, planes are generated beneath indentations on {0001} surfaces. Basal plane dislocations lying parallel to the surface are also observed. Indentations on {1100} prismatic surfaces result in slip on {0001} and {0110} planes.     

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.     

Dislocations in indented Ga0·7 Al0·3As

Abstract

Transmission electron microscope observations have been made of dislocations in Ga_0·7Al_0·3As after indentation of (001) surfaces at room temperature. Using two-beam imaging, in bright-field and weak-beam imaging, dissociated dislocations with extended stacking faults were observed both in the [110] and [110] directions. This is different from GaAs in which dissociated dislocations are seen in only one of these directions. These results are compared with published work on indented GaAs and considered in the light of possible mechanisms.     

Inversion domain boundary in a ZnO film

Transmission electron microscopy has been used to investigate the (1100) and (1103) inversion domain boundaries in a ZnO film prepared by molecular beam epitaxy. The inversion domain was revealed by dark-field images and confirmed by convergent-beam electron diffraction. Interacting with a (0002) stacking fault, the inversion domain boundary in the (1100) plane alters its orientation from the [0001] direction and climbs on the (1103) plane to release the strain energy. These features are characterized and analysed by high-resolution electron microscopy and the geometric phase method. The findings are significant for understanding the formation and propagation of inverse domain boundaries in epitaxial ZnO films.     

Precipitate characteristics and selected area diffraction patterns of the β′ and Q′ precipitates in Al–Mg–Si–Cu alloys

In this study, the precipitate characteristics and selected area diffraction patterns (SADP) of the β?′ and Q?′ precipitates formed at the over-aged state of Al–Mg–Si–Cu alloys are systematically investigated by means of high-resolution transmission electron microscopy and transition matrix. The β?′ precipitates have two cross-sections, rectangle-shaped and round-shaped aligned with [0?0?1]_Al direction, but only rectangle-shaped cross-section exists for Q?′ precipitates. And, both of them have 12 variants and orientations with Al matrix. However, there are only three different zone axes, [0?0?0?1]_β?′, [1?4?5?0]_β?′, and [5?4?1?0]_β?′ for β?′ precipitates, and [0?0?0?1]_Q?′, [1?4?5?0]_Q?′, and [3?2 1?0]_Q?′ for Q?′ precipitates, parallel to the [0?0?1]_Al direction when they are precipitated from the Al matrix, respectively. Then, a new [0?0?1]_Al SADP model, which superposes diffraction patterns of the β?′ and Q?′ precipitates, is established. Furthermore, some “cross-shaped” diffraction streaks appeared at over-aged state can be explained reasonably by this model, which is good in agreement with the experimental data.     

Algebraic Functions

Let A be an algebra. We say that the functions f ₁, . . . , f _m : A ⁿ ?? A are algebraic on A provided there is a finite system of term-equalities ${{\bigwedge t_{k}(\overline{x}, \overline{z}) = s_{k}(\overline{x}, \overline{z})}}$ satisfying that for each ${{\overline{a} \in A^{n}}}$ , the m-tuple ${{(f_{1}(\overline{a}), \ldots , f_{m}(\overline{a}))}}$ is the unique solution in A ^m to the system ${{\bigwedge t_{k}(\overline{a}, \overline{z}) = s_{k}(\overline{a}, \overline{z})}}$ . In this work we present a collection of general tools for the study of algebraic functions, and apply them to obtain characterizations for algebraic functions on distributive lattices, Stone algebras, finite abelian groups and vector spaces, among other well known algebraic structures.     

HRTEM study of the {252}γ austenite–martensite interface in an Fe—8Cr–1C alloy

Abstract

High-resolution transmission electron microscopy has been used to image the atomic structure of the (2S2)_γ austenite-martensite interface. By imaging along [101]_γ ∥[111]_α, the interface was viewed edge-on and seen to consist of facets on the close-packed (111)_γ, planes. From the correspondence of atoms in the close-packed planes across the austenite-martensite interface, the magnitude of the shear can be analysed as (a/24)<112> on every close-packed plane in the plane of projection. Comparison with theory indicates that this is an (a/12)<112> Burgers vector out of the plane of projection. Hence, each atomic facet can be viewed as a structural ledge containing an (a/12)<112> transformation dislocation.     

X-ray study of phason strain in Al-based quasicrystals

Abstract

X-ray powder diffraction spectra have been measured for melt-spun Al-Si–Mn, Al-Cu–Fe and Al-Li–Cu and Bridgman-grown Al-Li-Cu quasicrystals to investigate the phason strain frozen during the solidification process. For the melt-spun samples, most of the peaks have a shoulder or a tail which is attributed to the anisotropic linear phason strain. The peak shapes for the three melt-spun samples are essentially the same, which indicate that the same type of linear phason is quenched in these samples. In contrast, symmetric peak shapes without shoulders nor tails are seen for the Bridgman-grown Al-Li–Cu, indicating that it contains little linear phason strain.

Our findings are discussed with respect to the three linear phason models which can be derived by degradation of the symmetry from ideal icosahedral group m35 to its maximal subgroups 3m, m3 and 5m. Of these three, the model for 3m reproduces best the observed shapes and widths of the peaks.     

Planar faults in MoSi2 single crystals deformed at high temperatures

Abstract

Dislocation structure and planar faults have been examined in MoSi₂ single crystals deformed at high temperatures. Pure stacking faults were found in a crystal deformed at 900°C. The formation of the stacking fault is closely related to the phase stability of the C11_b and C40 ordered structures. Profuse stacking faults with increasing deformation temperature assist the ductility improvement of the MoSi₂ above about 1200°C. The critical resolved shear stress for {110}(331) and {013}(331) slip is determined in the temperature range 1000 to 1500°C.     

A Survey of Rewards for Teens: Extension and 25-Year Follow-Up

Extant reward surveys and item preferences assessments have shown to be a reliable mode of ascertaining potential reinforcers for various populations; however, many are outdated and may comprise of items or rewards that contemporary populations may not value. The purpose of this research is to extend upon the Houlihan, Jesse, Levine, and Sombke (1991 Houlihan, D., Jesse, V. C., Levine, H. D., &; Sombke, C. (1991). A survey for use with teenage children. Child &; Family Behavior Therapy, 13(1), 1–11.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) Survey of Rewards for Teens (SORT) and assess whether there is evidence of a potential, generational shift in reward preferences in high school students from 1991 to 2016. This inquiry is of particular importance to behavior analysts due to the idiosyncratic nature of reward preference, a tendency for rewards to shift over time, and the salient role played by rewards in behavior therapy programs. Results suggest that the reward preferences of contemporary high school students differ when compared to the sample of adolescents in Houlihan et al. (1991 Houlihan, D., Jesse, V. C., Levine, H. D., &; Sombke, C. (1991). A survey for use with teenage children. Child &; Family Behavior Therapy, 13(1), 1–11.[Taylor &; Francis Online], [Web of Science ®] , [Google Scholar]) study. In addition, a proposed revision of the SORT is provided, whose development was derived based on the resulting component structure from a principal components analysis (PCA) and inspection of component psychometric properties.     

The Pari[ndot]āma Aesthetics as Underlying the Bhāgavata Purā[ndot]a

This paper offers a literary and ideological deconstruction of the Bhāgavata Purā[ndot]a; it traces the Purā[ndot]a's formation through the convergence of the Vedāntin, the Aesthetic and the Vai[sdot][ndot]ava traditions, and argues that it is the doctrine of Pari[ndot]āma which underlies the treatise. I first examine the Bhāgavata Purā[ndot]a's literary components; the roots of these are traced back historically to the Vedānta and ālvār traditions, and the Bhāgavata Purā[ndot]a's nature as an opus universale, representing an all Indian cultural ‘melting pot’, is highlighted. The paper then looks at the relations of Vai[sdot][ndot]avism and dramaturgy, both historically as well as theologically, and argues that the Bhāgavata Purā[ndot]a was traditionally read as a drama. It proceeds to decipher the aesthetic theory underlying the Bhāgavata Purā[ndot]a, and argues that it is Bharata's dramaturgical rasa theory. Within the rasa tradition, Abhinavagupta's and Bhoja's positions are highlighted and compared through three seminal points and it becomes apparent that the Bhāgavata Purā[ndot]a's underlying aesthetic theory is close to the Pari[ndot]āma doctrine of Bhoja where ?[rdot][ndot]gāra is considered to be the supreme rasa. As Bhoja's date is no doubt later than the Bhāgavata Purā[ndot]a's it is assumed that the Bhāgavata Purā[ndot]a was influenced by one of Bhoja's predecessors. The paper ends by reinforcing this analysis by highlighting a later tradition which had actually accepted this point of view and that is the Gau[ddot]iya Vai[sdot][ndot]ava tradition.     

The Role of Effort–Reward Imbalance for Reservists on a Military Deployment

The present study extended the effort–reward imbalance (ERI) model (Siegrist, 1996b Siegrist, J. 1996b. “Soziale Krisen und Gesundheit [Social crises and health]”. In Gesundheitspsychologie [Health psychology] Edited by: Krohne, H. W., Schmidt, L., Netter, P. and Schwarzer, R. Vol. 5, Göttingen, , Germany: Hogrefe.  [Google Scholar]), first by differentiating between separate reward components, second by including intrinsic reward, and third by additionally predicting a non-health outcome (i.e., turnover intention) in a military context. Regression analyses of 789 reservists found financial and esteem reward to moderate the impact of extrinsic effort on depressive symptoms, whereas only financial reward moderated the effort turnover intentions relationship. Results supported the usefulness of the extended ERI model in the military context. Relevant areas for future research on the military effort–reward perspective are discussed.     

CBT for Children and Adolescents With High-Functioning Autism Spectrum Disorders,edited by A. Scarpa,S. Williams White, & T. Attwood

ABSTRACT

Parent-Child Interaction Therapy (PCIT) is a manualized behavioral intervention originally developed by Eyberg (1988 Eyberg, S. (1988). Parent-child interaction therapy: Integration of traditional and behavioral concerns. Child &; Family Behavior Therapy, 10(1), 33–46. doi:10.1300/j019v10n01_04[Taylor &; Francis Online] , [Google Scholar]) to address disruptive behaviors in young children. Although previous research findings support the contention that components of PCIT would positively impact communication, behavior, and adaptive skills (Howard, Sparkman, Cohen, Green, &; Stanislaw, 2005; Lovaas, 1987 Lovaas, O. I. (1987). Behavioral treatment and normal educational and intellectual functioning in young autistic children. Journal of Consulting and Clinical Psychology, 55(1), 3–9. doi:10.1037/0022-006x.55.1.3[Crossref], [PubMed], [Web of Science ®] , [Google Scholar]; Remington et al., 2007 Remington, B., Hastings, R. P., Kovshoff, H., Degli Espinosa, F., Jahr, E., Brown, T., &; Ward, N. (2007). Early intensive behavioral intervention: Outcomes for children with autism and their parents after two years. American Journal on Mental Retardation, 112(6), 418–438. doi:10.1352/0895-8017(2007)112[418:eibiof]2.0.co;2[Crossref], [PubMed] , [Google Scholar]) in children with developmental disabilities, few studies are shown in the literature. In a modified version of PCIT, caregivers completed two phases of intervention with their child diagnosed with Autism Spectrum Disorder (ASD). During the Child-Directed Interaction (CDI) phase, caregivers were taught to conduct mand training, follow-their child’s lead, provide attention for their child’s positive behaviors, and ignore their child’s negative behaviors. During the Parent-Directed Interaction (PDI) phase, caregivers were taught to give effective commands and follow through with demands. The goal of the current study was to determine whether children’s production of vocalizations increased after participation in a modified PCIT program. Data from two participants diagnosed with autism were included in the study. Outcomes of these two case studies show that both children displayed an increase in the total number of vocalizations emitted in the posttreatment observation relative to baseline. Additionally, caregivers of both participants displayed an increased number of positive behaviors in the posttreatment observation relative to baseline.     

Failure Causes Fear: The Effect of Self-Esteem Threat on Death-Anxiety

ABSTRACT

According to terror management theory (TMT; Greenberg, Pyszczynski, 1986 Greenberg, J., Pyszczynski, T. and Solomon, S. 1986. “The causes and consequences of a need for self-esteem: A terror management theory”. In Public self and private self, Edited by: Baumeister, R. F. 189–212. New York, NY: Springer-Verlag. doi:10.1007/978-1-4613-9564-5_10[Crossref] , [Google Scholar]), self-esteem protects people from anxiety associated with the knowledge of certain mortality. A number of studies provide evidence consistent with this assertion, but no studies have experimentally examined the effect of threatened self-esteem on death-anxiety. In the current study, self-esteem was manipulated and death-anxiety measured. A self-esteem threat increased death-anxiety relative to a self-esteem boost and non-self threat control condition.     

The Impact of the Wording of Employment Advertisements on Students' Inclination to Apply for a Job

ABSTRACT

Students' inclination to apply for a job was examined as a function of (1) the wording of the desired candidate's profile specified in the employment advertisement and (2) applicant gender. Previous research found that women are more inclined than men to apply for jobs that include a profile corresponding to their gender (i.e., a profile containing prototypically feminine instead of masculine personal characteristics). Based on Fiedler and Semin's (1996) Fiedler, K. and Semin, G. R. 1996. “Language in applied contexts”. In Applied social psychology, Edited by: Fiedler, K. and Semin, G. R. 91–109. Thousand Oaks, CA: Sage.  [Google Scholar] Linguistic Category Model, we expected that this effect would decrease if the desired profile was worded in terms of behaviors/verbs instead of nouns/adjectives. ANOVA supported this reasoning for women but not for men. We conclude that organizations may increase the number of women applying for particular jobs by changing the presentation form of the advertisement.     

Importing Logics

The novel notion of importing logics is introduced, subsuming as special cases several kinds of asymmetric combination mechanisms, like temporalization [8, 9], modalization [7] and exogenous enrichment [13, 5, 12, 4, 1]. The graph-theoretic approach proposed in [15] is used, but formulas are identified with irreducible paths in the signature multi-graph instead of equivalence classes of such paths, facilitating proofs involving inductions on formulas. Importing is proved to be strongly conservative. Conservative results follow as corollaries for temporalization, modalization and exogenous enrichment.     

Dispositional forgiveness among adolescents

The study examined whether the four constructs of forgivingness found in adults—propensity to lasting resentment, sensitivity to circumstances, willingness to forgive, and willingness to avenge—were already in place among adolescents. It also examined the differences in propensity to forgive and related constructs between young adolescents and older adolescents. More than 500 adolescents (124 sixth graders, 170 seventh graders, 135 eighth graders, and 78 ninth graders) were presented with a slightly modified version of the Forgivingness Scale (Mullet, Barros, Frongia, Usai, Neto, & Rivière-Shafighi, 2003 Mullet, E., Barros, J., Frongia, L., Usai, V., Neto, F. and Rivière-Shafighi, S. 2003. Religious involvement and the forgiving personality. Journal of Personality, 71: 1–19. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]). The same four-factor structure that was found among adults was also found among adolescents. Scores regarding sensitivity to circumstances and willingness to forgive were lower among older adolescents than among younger adolescents. Scores regarding lasting resentment and willingness to avenge were higher among older adolescents than among younger adolescents.     

Expert and “novice” problem solving strategies in chess: Sixty years of citing de Groot (1946)

In a famous study of expert problem solving, de Groot (1946 de Groot, A. D. 1946. Het denken van den schaker, Amsterdam: Noord Hollandsche.  [Google Scholar]/1978 de Groot, A. D. 1965. Thought and choice in chess, The Hague: Mouton Publishers.  [Google Scholar]) examined how chess players found the best move. He reported that there was little difference in the way that the best players (Grand Masters) and very good players (Candidate Masters) searched the board. Although this result has been regularly cited in studies of expertise, it is frequently misquoted. It is often claimed that de Groot found no difference in the way that experts and novices investigate a problem. Comparison of expert and novice chess players on de Groot's problem shows that there are clear differences in their search patterns. We discuss the troublesome theoretical and practical consequences of incorrectly reporting de Groot's findings.