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Educators around the world have been challenged to adapt their teaching and pastoral care rapidly in response to the coronavirus pandemic. In this article, we, the academic members of the Chemistry Education and Communication Research Theme (CECR) from the School of Chemistry at the University of Sydney, reflect on the challenges and successes over the course of this most unusual semester. We have included discussions on the specific tools and techniques we employed, in light of the available literature, across the range of modes in which we teach, including lectures, tutorials, and laboratories. As many of us prepare to begin or continue teaching, we hope the experiences and lessons we have learned can offer some assistance to our disciplinary colleagues around the world.

How students behave and learn in the teaching laboratory is a topic of great interest in chemical education, partly in order to justify the great expense of teaching laboratories. Much effort has been put into investigating how students think, feel and physically act in these unique learning environments. One such attempt was made through the generation and utilisation of the Meaningful Learning in the Laboratory Instrument (MLLI). This 30 question survey utilised Novak's theory of Meaningful Learning to investigate the affective, cognitive and psychomotor domains of the student learning experience. To date, this survey has been used to great effect to measure how students' perception of their own feelings and actions will change over the course of a semester. This study reports the use of a modified MLLI survey to probe how the expectations of students change over their undergraduate degree. To increase the generalisability of the outcomes of the study data was gathered from four universities from Australia (Monash University, the University of New South Wales and the University of Sydney) and the UK (the University of Warwick). Students were found to start their university careers with very positive expectations of their teaching laboratory experiences. Their outlook became somewhat more negative each year that they were enrolled in the program. A further modified MLLI survey was presented to teaching associates and academic staff. Teaching staff were shown to have far more negative expectations of the students' feelings and actions, with academic staff more likely to believe that students do not undertake many items of positive meaningful learning. Overall, this study highlights the large gap between the expectations of teaching staff and students which, if left unaddressed, will likely continue to cause great frustration for both teaching staff and students.

This study focuses on zinc-boro-soda-lime-silica (ZnO − B2O3 − SLS) glasses produced through fast-cooling melt-quenching. The influence of Eu3+ ions on glass properties is explored. As Eu3+ concentration rises, bulk density and molar volume increase from 3.423 to 3.484 g/cm3 and 21.760 to 23.768 cm3/mol, respectively. X-ray diffraction indicates amorphous phase dominance supported by glassy surface morphology. Ultrasonic measurements show the increasing and decreasing trend for ultrasonic velocities and elastic moduli with increasing Eu3+ concentration. Poisson's ratio of the samples signifies their low cross-link density behavior. Moreover, the ZBS-3Eu presents the highest microhardness value of 4.776 GPa. The sample's fractal bond connectivity varies from 1.814 to 2.051, suggesting a 2D structure. Likewise, the ZBS-3Eu glass sample exhibits the most rigidity attributed to its highest fg value of 0.075. These findings suggest that ZBS-3Eu has the potential for applications requiring high-strength glass. [ABSTRACT FROM AUTHOR]

This paper reports a novel lead-free tungsten bronze type ceramic, Sr5BiTi3Nb7O30, prepared by a conventional high-temperature solid-state reaction route. The crystal structure identified using synchrotron x-ray diffraction data and Raman spectroscopy for Sr5BiTi3Nb7O30 could be described as an average structure with the centrosymmetric space group P4/mbm and a local non-centrosymmetric structure at room temperature. In the second-harmonic generation measurement, the Sr5BiTi3Nb7O30 compound exhibits second-order nonlinear optical behavior, which suggests the material is ferroelectric. Temperature dependence of the dielectric permittivity indicates that the dielectric anomaly in Sr5BiTi3Nb7O30, associated with the disorder on the A and B sites, results in strong frequency dispersion with a low phase-transition temperature. A macroscopic and phenomenological statistical model was employed to describe the temperature dependence of the dielectric responses of Sr5BiTi3Nb7O30 and Sr6Ti2Nb8O30. The calculated sizes of polar nanoregions for both compounds imply structural disorder induced by A and B sites, giving rise to a more diffuse ferroelectric transition for Sr5BiTi3Nb7O30. The smaller polar nanoregions with smaller electrical dipole moments can be activated at lower temperatures, leading to Sr5BiTi3Nb7O30 having a lower Tm (∼260 K) than other tungsten bronze type ferroelectrics. This work charts a promising feasible route to the development of improved relaxor ferroelectrics in tungsten bronze type oxides. [ABSTRACT FROM AUTHOR]

This paper reports a novel lead-free tungsten bronze type ceramic, Sr5BiTi3Nb7O30, prepared by a conventional high-temperature solid-state reaction route. The crystal structure identified using synchrotron x-ray diffraction data and Raman spectroscopy for Sr5BiTi3Nb7O30 could be described as an average structure with the centrosymmetric space group P4/mbm and a local non-centrosymmetric structure at room temperature. In the second-harmonic generation measurement, the Sr5BiTi3Nb7O30 compound exhibits second-order nonlinear optical behavior, which suggests the material is ferroelectric. Temperature dependence of the dielectric permittivity indicates that the dielectric anomaly in Sr5BiTi3Nb7O30, associated with the disorder on the A and B sites, results in strong frequency dispersion with a low phase-transition temperature. A macroscopic and phenomenological statistical model was employed to describe the temperature dependence of the dielectric responses of Sr5BiTi3Nb7O30 and Sr6Ti2Nb8O30. The calculated sizes of polar nanoregions for both compounds imply structural disorder induced by A and B sites, giving rise to a more diffuse ferroelectric transition for Sr5BiTi3Nb7O30. The smaller polar nanoregions with smaller electrical dipole moments can be activated at lower temperatures, leading to Sr5BiTi3Nb7O30 having a lower Tm (∼260 K) than other tungsten bronze type ferroelectrics. This work charts a promising feasible route to the development of improved relaxor ferroelectrics in tungsten bronze type oxides. [ABSTRACT FROM AUTHOR]

In this work, Eu3+/Sm3+ co-doped zinc borosilicate glass was prepared by modified melt-quenching method. The effect of Eu3+/Sm3+ to the structural and optical properties was investigated. The optical band gaps increased from 5.023 to 5.179 eV, and 3.832 to 3.986 eV for both for direct/indirect transition. Urbach energy decreases from 0.713 to 0.697 eV, while refractive index also decreases from 2.203 to 2.173 with the progress of doping concentration. The photoluminescence measurement reveals the simultaneous amplification of Sm3+ and Eu3+ emission for the co-doping sample, suggesting a synergistic energy transfer between the two ions. The 1EuSmZBS glass samples show the highest emission intensity. The CIE chromaticity coordinates, CCT, and color purity of the glass sample present high intensity of reddish-orange emission color. In conclusion, Eu3+/Sm3+ co-doped zinc borosilicate glass can lead to enhanced and tunable luminescence properties, and potentially use as a glass host phosphor in optoelectronic applications. [ABSTRACT FROM AUTHOR]

Chemistry education focused on learning outcomes is increasingly practiced, providing new opportunities for international comparisons. The interest in intended learning outcomes and constructive alignment has grown in many parts of the world due to both research in higher education and political decisions. In an International Union of Pure and Applied Chemistry (IUPAC) project, we have developed a method of using critical evaluation of learning outcomes and descriptors at international, national, and institutional levels to enhance learner-centered chemistry education. This method is process-focused, aimed at learning by sharing and comparing practices around the world. Three overarching documents for the chemistry bachelor from the USA, Europe and Australia were compared. The differences were found to be more in style than in content. A tool for self-analysis was constructed to evaluate how learning outcomes for courses and modules are linked to each other and to learning outcomes for educational programs and how the expected learning outcomes can be aligned with learning activities and assessment. We conclude that the method can be used to elucidate the correspondence between learning outcomes at different levels, and the constructive alignment between learning outcomes, learning activities and assessment. The process gives new perspectives and shared knowledge. Chemistry education may need to be different depending on local considerations, and awareness of these differences is of value for further development.

Bridging courses designed to support students commencing tertiary education are widespread, and some evidence for the value of semester-length courses has been reported; however, little attention has been paid to short-but-intense bridging courses, and empirical evidence of their effectiveness is particularly sparse. The current study followed the academic performance of a cohort of students enrolled in a first-year chemistry unit of study designed for those with little or no background knowledge of chemistry. The aims of this study are two-fold: first to determine the strength of the linkage between prior knowledge in chemistry and performance on the end of semester exam, and secondly, to explore the reasons for any differences observed. In particular, the value of the week-long intensive-mode bridging course offered by the University of Sydney was analysed. Quantitative and qualitative data were collected. The research has shown that participation in the chemistry bridging course is associated with "bridging the gap" in academic performance between students with No Prior Chemistry background and those with a Strong Background. While the content of the bridging course is a significant contributor to academic success, so too is the confidence in their own learning that the course engenders among participants. (Contains 7 figures.)