The Theory and Practice of Third Phase Science

2014 ◽  
pp. 129-145 ◽  
Author(s):  
Kenneth C. Bausch
Keyword(s):  
Theory And Practice ◽  
Third Phase

Precipitation of NiHfsi phase in NiAl single crystals containing Hf

1995 ◽  
Vol 53 ◽  
pp. 532-533
Author(s):  
A. Garg ◽  
R. D. Noebe ◽  
R. Darolia
Keyword(s):  
High Temperature ◽  
Single Crystals ◽  
High Temperature Strength ◽  
Bridgman Technique ◽  
Shell Mold ◽  
Third Phase ◽  
Unknown Phase ◽  
Transmission Electron ◽  
Two Phases ◽  
Nial Matrix

Small additions of Hf to NiAl produce a significant increase in the high-temperature strength of single crystals. Hf has a very limited solubility in NiAl and in the presence of Si, results in a high density of G-phase (Ni16Hf6Si7) cuboidal precipitates and some G-platelets in a NiAl matrix. These precipitates have a F.C.C structure and nucleate on {100}NiAl planes with almost perfect coherency and a cube-on-cube orientation-relationship (O.R.). However, G-phase is metastable and after prolonged aging at high temperature dissolves at the expense of a more stable Heusler (β'-Ni2AlHf) phase. In addition to these two phases, a third phase was shown to be present in a NiAl-0.3at. % Hf alloy, but was not previously identified (Fig. 4 of ref. 2 ). In this work, we report the morphology, crystal-structure, O.R., and stability of this unknown phase, which were determined using conventional and analytical transmission electron microscopy (TEM).Single crystals of NiAl containing 0.5at. % Hf were grown by a Bridgman technique. Chemical analysis indicated that these crystals also contained Si, which was not an intentional alloying addition but was picked up from the shell mold during directional solidification.

Addressing the Content Vocabulary With Core: Theory and Practice for Nonliterate or Emerging Literate Students

2012 ◽  
Vol 21 (3) ◽  
pp. 74-81 ◽  
Author(s):  
Debbie Witkowski ◽  
Bruce Baker
Keyword(s):  
Communication Skills ◽  
High Performance ◽  
Theory And Practice ◽  
Written Communication ◽  
Academic Tasks ◽  
Meaningful Participation ◽  
Core Theory ◽  
Communication Needs ◽  
Core Vocabulary ◽  
Personal Success

Abstract In the early elementary grades, the primary emphasis is on developing skills crucial to future academic and personal success—specifically oral and written communication skills. These skills are vital to student success as well as to meaningful participation in the classroom and interaction with peers. Children with complex communication needs (CCN) may require the use of high-performance speech generating devices (SGDs). The challenges for these students are further complicated by the task of learning language at a time when they are expected to apply their linguistic skills to academic tasks. However, by focusing on core vocabulary as a primary vehicle for instruction, educators can equip students who use SGDs to develop language skills and be competitive in the classroom. In this article, we will define core vocabulary and provide theoretical and practical insights into integrating it into the classroom routine for developing oral and written communication skills.

The Measurement Invariance of the Short Dark Triad

2020 ◽  
Vol 41 (4) ◽  
pp. 207-218
Author(s):  
Mihaela Grigoraș ◽  
Andreea Butucescu ◽  
Amalia Miulescu ◽  
Cristian Opariuc-Dan ◽  
Dragoș Iliescu
Keyword(s):  
Structural Equation Modeling ◽  
Item Response ◽  
Structural Equation ◽  
Dark Triad ◽  
Theory And Practice ◽  
Equation Modeling ◽  
Scale Level ◽  
High Stake ◽  
Differential Functioning ◽  
Item Functioning

Abstract. Given the fact that most of the dark personality measures are developed based on data collected in low-stake settings, the present study addresses the appropriateness of their use in high-stake contexts. Specifically, we examined item- and scale-level differential functioning of the Short Dark Triad (SD3; Paulhus & Jones, 2011 ) measure across testing contexts. The Short Dark Triad was administered to applicant ( N = 457) and non-applicant ( N = 592) samples. Item- and scale-level invariances were tested using an Item Response Theory (IRT)-based approach and a Structural Equation Modeling (SEM) approach, respectively. Results show that more than half of the SD3 items were flagged for Differential Item Functioning (DIF), and Exploratory Structural Equation Modeling (ESEM) results supported configural, but not metric invariance. Implications for theory and practice are discussed.

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