This contribution describes the preparation and characterization of PEO/montmorillonite nanocomposite gels and films containing various lithium and sodium salts. The objective is to understand how ...the size and diffusion abilities of different ionic species added to these systems alter the crystallinity of the polymer, and affect the mechanical properties and ionic conductivities of the solid nanocomposites. The network strength of the polymer/clay dispersions influences decisively the crystallinity of the PEO chains and the final layered texture of the solid films. The characteristics of films were investigated using a combination of techniques, such as DSC, DMA, DEA, SEM, SAXS and XRD.
The development of an alternative method in the assessment of critical thinking as an outcome of nursing education
Rationale. Critical thinking is currently a highly valued educational outcome ...throughout the educational spectrum, but particularly so in relation to higher and professional education. Nursing education worldwide is also embracing the construct critical thinking as a desirable educational outcome, to the extent that some commentators refer to the importance of critical thinking in nursing as a given. The body of evidence relating to the impact that nursing education has upon the development of critical thinking is currently inconclusive. Many commentators claim that this may be because the instruments used in many studies are not sufficiently domain‐specific.
Study aims. The primary purpose of this descriptive‐illuminative study was to explore and develop an alternative domain‐specific method for identifying critical thinking in student nurses’ reasoning processes.
Design. A longitudinal multimethod design incorporating across‐method triangulation has been utilized for this purpose. Data collection from a group of student nurses involved the combination of the Watson and Glaser (1991) critical thinking appraisal test and a researcher developed think aloud technique incorporating a videotaped client simulation, a cognitive task and stimulated recall strategy.
Findings. Findings indicate no significant differences in pre and postprogramme Watson–Glaser mean scores. With regard to the think aloud evidence the sample consistently displayed evidence of reasoning that reflected an absolutist epistemology portraying limited evidence of critical thinking. In instances where more complex reasoning was demonstrated there was evidence to suggest that metacognitive strategies may contribute to this phenomenon.
Conclusions. The findings make a further contribution to the assessment of critical thinking and raise interesting challenges to future curriculum development in nursing education, assessment of learning and nursing practice.
The purpose of the present contribution is to provide an efficient method that would help to quantify the orientational levels occurring in polymer/clay dispersions subjected to elongational flow. ...The extent of internal orientation developed in salt containing montmorillonite/poly(ethylene oxide) gels is investigated, combining shear and elongational rheology methods. Entropic changes indicate that the strength of the transient network present in each gel affects the orientational ability of clay particles and polymer chains. We found that an increased Hencky strain of the hyperbolic die leads to a higher variation of the calculated entropy of the material.
The aim of the present contribution is to understand how ionic strength, brought by the addition of salt to laponite/PEO nanocomposite dispersions, influences the texture and adhesion characteristics ...at nano‐ and microscales in multilayered nanocomposite films prepared from such dispersions. At the nano‐scale, SAXS and XRD measurements indicated that the clay platelets orient parallel to the film plane and that the polymer chains intercalate the clay platelets regardless of salt addition. A gradual transition from an agglomerated structure, containing polymer‐rich and clay‐rich domains, to a fine‐balanced structure with smaller distinct details without excess PEO was observed, via AFM, on the exposed edges of cryo‐microtomed films with increasing ionic strength.
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