Search results for "PET"
showing 10 items of 12749 documents
Applications of xylochemistry from laboratory to industrial scale
2020
Xylochemicals and their utilisation in total synthesis and industrial applications are highlighted in this review. This class of chemicals consists of bio-based molecules or building blocks derived from renewable feedstocks like plant-biomass, lignocellulose as well as waste-streams. The advantages over petroleum-based chemicals are presented with the aid of specific examples ranging from the total synthesis of natural products, relevant industrial applications to the exploitation of CO2 as a C1 feedstock. This review contributes to the trend of a “greener” and a more sustainable chemistry.
Benefits of computer screen-based simulation in learning cardiac arrest procedures
2010
Medical Education 2010: 44: 716–722 Objectives What is the best way to train medical students early so that they acquire basic skills in cardiopulmonary resuscitation as effectively as possible? Studies have shown the benefits of high-fidelity patient simulators, but have also demonstrated their limits. New computer screen-based multimedia simulators have fewer constraints than high-fidelity patient simulators. In this area, as yet, there has been no research on the effectiveness of transfer of learning from a computer screen-based simulator to more realistic situations such as those encountered with high-fidelity patient simulators. Methods We tested the benefits of learning cardiac arre…
Rigidity of quasisymmetric mappings on self-affine carpets
2016
We show that the class of quasisymmetric maps between horizontal self-affine carpets is rigid. Such maps can only exist when the dimensions of the carpets coincide, and in this case, the quasisymmetric maps are quasi-Lipschitz. We also show that horizontal self-affine carpets are minimal for the conformal Assouad dimension.
Factors affecting Nigerian teacher educators’ technology integration : Considering characteristics, knowledge constructs, ICT practices and beliefs
2020
To provide a diverse comprehension of teachers' TPACK (Technological, Pedagogical, and Content Knowledge) and how TPACK is reflected in practice, this study examined teacher educators' (TEs') conceptions of technology integration. Specifically, the main objective of the study was to investigate the factors influencing Nigerian teacher educators' technology integration using a self-completion survey administered to Nigerian teacher educators from three schools in the southern region of Nigeria. We utilized the partial least squares structural equation modeling (PLS-SEM) approach for the data analysis. Two frameworks—TPACK and Second Information Technology in Education Study (SITES)— guided t…
Professional vision of Grade 1 teachers experiencing different levels of work-related stress
2022
This study explored teachers' professional vision by examining how teachers experiencing low, moderate and high work-related stress reason their eye-tracking recordings in terms of description, explanation and prediction. A qualitative analysis of retrospective think-aloud interviews with 24 Grade 1 teachers showed that teachers predominantly used description in their reasoning, while explanation and prediction were less frequent. The description mainly focused on teacher information/elaboration and classroom management/behaviour. Teachers with moderate stress utilised self-reflection most frequently, whereas teachers with high stress utilised it the least. The results suggest that the leve…
‘The teacher almost made me cry’ Narrative analysis of teachers' reactive classroom management strategies as reported by students diagnosed with ADHD
2016
This interview study addresses the gap in earlier research by focussing on the narratives of 13 ADHDdiagnosed Finnish students regarding teacher reactive classroom management strategies. The data are analysed through narrative analysis. Five different narrative types are identified, in which teacher behaviour is evaluated as (1) disproportionate, (2) traumatising, (3) neglectful, (4) unfair and (5) understanding. The dominant storyline e common to the first four types e constructed the narrator's transgression as contingent upon and a justified reaction to teacher conduct. The vicious cycle of coercive classroom management strategies and the culture of blame between students and teachers ar…
Microstructural evolution of gas hydrates in sedimentary matrices observed with synchrotron X-ray computed tomographic microscopy
2015
The formation process of gas hydrates in sedimentary matrices is of crucial importance for the physical and transport properties of the resulting aggregates. This process has never been observed in situ at submicron resolution. Here we report on synchrotron-based microtomographic studies by which the nucleation and growth processes of gas hydrate were observed at 276 K in various sedimentary matrices such as natural quartz (with and without admixtures of montmorillonite type clay) or glass beads with different surface properties, at varying water saturation. Both juvenile water and metastably gas-enriched water obtained from gas hydrate decomposition was used. Xenon gas was employed to enha…
A computational and experimental investigation of halloysite silicic surface modifications after alkaline treatment
2023
Density functional theory calculations were performed in order to investigate the formation of silanol groups on the outer surface of halloysite nanotubes, as possible products of the reactions with water in alkaline environments. The results, discussed in terms of energy release and structural properties of the modified surface, suggest that the formation of various kinds of silanol group constellations, and even the extraction of orthosilicic acid, are highly exothermic reaction in the presence of hydroxide ions. Thermogravimetric analysis, FT-IR, XRD and X-ray fluorescence spectrometry performed on halloysite treated at high pH conditions indicate that the adsorption of water on the oute…
Characterisation of clayey raw materials for ceramic manufacture in ancient Sicily
2011
Abstract It is well known that mineralogical, petrographic and chemical analyses can successfully support provenance studies of archaeological ceramics. The characterisation of a ceramic paste, the assessment of its technology of production and its provenance assignment related to a specific production centre or to a geographical and/or compositional space, are all tasks that can be performed even more accurately if the clayey raw materials used in pottery production are also studied. For that reason the identification of the clay deposits exploited in a given ceramic workshop often plays a key role in the archaeometric reconstruction of the production cycle where geology, mineralogy, petro…
Eleonora Duse as Juliet and Cleopatra
2017
From her debut as Juliet in 1872 onwards, the career of Eleonora Duse (1858–1924) is marked by an evolving, changeable approach to her Shakespearean roles. In different ways and under diverse circumstances, each of her Shakespearean parts represented something of a turning-point in her cursus. Scholars have argued that life and art, emotional instinct and theatrical performance, coalesced seamlessly throughout her Shakespearean repertoire, and in particular in her interpretation of Cleopatra (Puppa 2009). Yet while this theory that she acted out her own personal life, and that her characters’ feelings coincided with her own, is an attractive one, it is also reductive. New evidence——the disc…