Charge compensation and Ce3+ formation in trivalent doping of the CeO2(110) surface: The key role of dopant ionic radius

In this paper, we use density functional theory corrected for on-site Coulomb interactions (DFT + U) and hybrid DFT (HSE06 functional) to study the defects formed when the ceria (110) surface is doped with a series of trivalent dopants, namely, Al3+, Sc3+, Y3+, and In 3+. Using the hybrid DFT HSE06 exchange-correlation functional as a benchmark, we show that doping the (110) surface with a single trivalent ion leads to formation of a localized MCe / + O O • (M = the 3+ dopant), O- hole state, confirming the description found with DFT + U. We use DFT + U to investigate the energetics of dopant compensation through formation of the 2MCe ′ +VO ̈ defect, that is, compensation of two dopants with an oxygen vacancy. In conjunction with earlier work on La-doped CeO2, we find that the stability of the compensating anion vacancy depends on the dopant ionic radius. For Al3+, which has the smallest ionic radius, and Sc3+ and In3+, with intermediate ionic radii, formation of a compensating oxygen vacancy is stable. On the other hand, the Y3+ dopant, with an ionic radius close to that of Ce4+, shows a positive anion vacancy formation energy, as does La3+, which is larger than Ce4+ (J. Phys.: Condens. Matter 2010, 20, 135004). When considering the resulting electronic structure, in Al3+ doping, oxygen hole compensation is found. However, Sc 3+, In3+, and Y3+ show the formation of a reduced Ce3+ cation and an uncompensated oxygen hole, similar to La3+. These results suggest that the ionic radius of trivalent dopants strongly influences the final defect formed when doping ceria with 3+ cations. In light of these findings, experimental investigations of these systems will be welcome.

Novel co-crystals of the nutraceutical sinapic acid

Sinapic acid (SA) is a nutraceutical with known anti-oxidant, anti-microbial, anti-inflammatory, anti-cancer, and anti-anxiety properties. Novel co-crystals of SA were prepared with co-formers belonging to the category of GRAS [isonicotinic acid (INC), nicotinamide (NIA)], non-GRAS [4-pyridinecarbonitrile (PYC)], and active pharmaceutical ingredients (APIs) [6-propyl-2-thiouracil (PTU)] list of compounds. Structural study based on the X-ray crystal structures revealed the intermolecular hydrogen-bonded interactions and molecular packing. The crystal structure of sinapic acid shows the anticipated acid-acid homodimer along with discrete hydrogen bonds between the acid carbonyl and the phenolic moiety. The robust acid-acid homodimer appears to be very stable and is retained in the structures of two co-crystals (SA[middle dot]NIA and SA[middle dot]PYC). In these cases, co-crystallization occurs via intermolecular phenol O-H[three dots, centered]Naromatic hydrogen bonds between the co-formers. In the SA[middle dot]PTU[middle dot]2MeCN co-crystal the acid-acid homodimer gives way to the anticipated acid-amide heterodimer, with the phenolic moiety of SA hydrogen-bonded to acetonitrile. Attempts at obtaining the desolvated co-crystal led to lattice breakdown, thus highlighting the importance of acetonitrile in the formation of the co-crystal. Among the co-crystals examined, SA[middle dot]INC (5 weeks), SA[middle dot]NIA (8 weeks) and SA[middle dot]PYC (5 weeks) were found to be stable under accelerated humidity conditions (40 [degree]C, 75% RH), whereas SA[middle dot]PTU[middle dot]2MeCN decomposed after one week into individual components due to solvent loss.

The implementation of a literacy intervention 'Station Teaching' in infant classes in Irish primary schools

Background: I conducted my research in the context of The National Literacy Strategy (DES, 2011), which maintains that every young person should be literate and it outlines targets for improving literacy in schools from 2011 to 2020. There has been much debate on the teaching of literacy and in particular the teaching of reading. Clark (2014) outlines how learning to read should be a developmental language process and that the approaches in the early years of schooling will colour the children’s motivation and their perception of reading as a purposeful activity. The acquisition of literacy begins in the home but this study focuses on the implementation of a literacy intervention Station Teaching in the infant classes in primary school. Station Teaching occurs when a class is divided into four or five small groups of pupils and they receive intensive tuition at four or five different Stations with the help of Support teachers: New Reading, Familiar Reading, Phonics, Writing and Oral Language. Research Questions: These research questions frame my study: How is Station Teaching implemented? What is the experience of the intervention Station Teaching from the participants’ point of view: teachers, pupils, parents? What notion of literacy is Station Teaching facilitating? Methods: I chose a pragmatic parallel mixed methods design as suggested by Mertens (2010). I collected and analysed both the quantitative and qualitative data to answer the study’s research questions. In the study the quantitative data were collected from a questionnaire issued to 21 schools in Ireland. I used Excel as a data management package and thematic analysis to analyse and present the data in themes. I collected qualitative data from a case study in a school. This data included observations of two classes over a period of a year; interviews with teachers, pupils and parents; children’s drawings, photographs, teachers’ diaries and video evidence. I analysed and presented the evidence from the qualitative data in themes. Main Findings: There are many skills and strategies that are essential to effective literacy teaching in the early years including phonological awareness, phonics, vocabulary, fluency, comprehension and writing. These skills can be taught during Station Teaching. Early intervention in the early years is essential to pupils’ acquisition of literacy. The expertise of the teacher is key to improving the literacy achievement of pupils Teachers and pupils enjoy participating in ST. Pupils are motivated to read and engage in meaningful activities during ST. Staff collaboration is vital for ST to succeed ST facilitates small group work and teachers can differentiate accordingly while including all pupils in the groups. Pupils’ learning is extended in ST but extension activities need to be addressed in the Writing Station. More training should be provided for teachers on the implementation of ST and more funding for resources should be available to schools Significant contribution of the work: The main significance of the study includes: insights into the classroom implementation of Station Teaching in infant classes and extensive research into characteristics of an effective teacher of literacy.

Learning to Teach and its Implications for the Continuum of Teacher Education: A Nine Country Cross-national Study.

The purpose of this Report is to inform discussions, policy formulation, and strategic planning on teacher education in Ireland. The research gives priority to initial teacher education (ITE) and induction, their interface, and implications for the continuum of teacher education, including continuing professional development (CPD). The study involved a two-pronged approach: a narrative review of recent and relevant literature and a cross-national review of teacher education policies in nine countries, namely, Ireland, Northern Ireland, Scotland, England, Finland, USA, Poland, Singapore and New Zealand. Adopting a broad, balanced and comprehensive understanding of the role of the contemporary teacher, it provides a framework for developing quality teacher education in Ireland. The Report incorporates exemplars of good practice and notes their implementation challenges for the Irish context.  Chapter One provides a framework for conceptualising quality teacher education and the continuum. Key features that emerge from the literature are discussed: teachers¿ practice, quality teaching, the professional life-cycle, teacher learning and relationships. With more specific reference to the continuum, Chapter Two overviews initial teacher education, induction, learning outcomes and accreditation in the selected countries, including Ireland. Key features of policy in the various countries are summarised. Individual country profiles, incorporating descriptions of socio-political, teaching and teacher education contexts, are further detailed in Appendix A. Chapter Three analyses relevant literature on initial teacher education, induction, learning outcomes/professional standards and accreditation. Along with previous chapters it provides the basis for recommendations for teacher education that are presented in Chapter Four. Chapter Four draws together the findings emerging from the cross-national review in terms of the contemporary context of teacher education in Ireland and identifies key challenges and possible lines of policy development as well as recommendations for the Teaching Council and other teacher education stakeholders. Each generation has an opportunity to provide the vision and resources for renewing teacher education in light of ambitious social, economic and educational aspirations to meet perceived societal and education challenges (as occurred in the 1970s). Despite the publication of two key reviews of initial teacher education a number of years ago, there is considerable scope for further reform of teacher education. However, significant changes have occurred to teacher education course provision and content over the last 100 years. In this report, we have stressed the need for, and called for investment in, greater system and programme coherence, mentoring to support assisted practice, knowledge integration, critical reflective practice, inquiry and the development of vibrant partnerships between higher education institutions and schools as the basis for teacher education reform across the continuum. This Executive Summary presents the Report¿s context, key findings and recommendations emerging from the analysis.  

The formation of nanotubes and nanocoils of molybdenum disulphide

This work reports the successful realization of MoS2 nanotubes by a novel intercalation chemistry and hydrothermal treatment. An inorganic-organic precursor of hexadecylamine (HDA) and molybdenum disulphide (MoS2) were used in synthesizing the nanocomposite comprising laminar MoS2 with HDA intercalated in the interlaminar spacing. The formation of MoS2 nanotubes occurred during hydrothermal treatment (HT) by a self-organized rolling mechanism. The nanotubes were observed to have dimensions 2-12 µm in length and inner diameters typically in the range of 25-100 nm. We also report the formation of amorphous nanocoils of MoS2 obtained during similar procedures.