Observations of transient high temperature vortical microstructures in solids during adiabatic shear banding

By using a unique infrared high-speed camera especially constructed for recording highly transient temperature fields at the microscale, we are able to reveal the spatial and temporal microstructure within dynamically growing shear bands in metals. It is found that this structure is highly nonuniform and possesses a transient, short range periodicity in the direction of shear band growth in the form of an array of intense "hot spots" reminiscent of the well-known, shear-induced hydrodynamic instabilities in fluids. This is contrary to the prevailing classical view that describes the deformations and the temperatures within shear bands as being essentially one-dimensional fields. These observations are also reminiscent of the nonuniform structure of localized shear regions believed to exist, at an entirely different length scale, in the earth's lower crust and upper mantle

Isolation and characterisation of 2-Tert-butyl-8-hydroxyquinoline as a crystalline solid and its blue fluorescent Li complex

Copyright © 2014 Poopathy Kathirgamanathan et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.2-Tert-butyl-8-hydroxyquinoline (2-TB-8-hq) has been isolated as a crystalline solid and its X-ray structure elucidated, resolving three decades of controversy, since it was previously wrongly reported as yellow oil by some other workers. An improved synthetic method has been developed which increases the yield from 20% to 60%. The lithium complex of 2-TB-8-hq is blue emitting and the HOMO and LUMO levels are lowered by 0.86 eV and 0.74 eV, respectively, compared with the parent lithium 8-hydroxyquinolinolate (Li 8-hq)

Segregation and flow characterization in vibrated hopper

Experiments and numerical simulation studies were carried. out on vertically vibrated wedge-type hoppers containing binary mixtures for the present research. The studies focussed on segregation analysis of the hopper discharge and the characterization of flow pattern of the binary mixtures in sealed hoppers, over wide ranges of frequency and amplitude of acceleration to determine the effect of these parameters. The results of segregation study show that vibration promotes segregation of the binary mixtures. However, increase in frequency was found to make the contents of segregated discharge more uniform. Also, increase in wedge angle seemed to help in reducing segregation. The experimentally observed flow patterns, showed a new type of four-loop convection pattern. The simulation studies revealed some of the experimental observations. Thus, the experimentally observed patterns included three regimes, namely, an unstable heaping state, symmetrical convection pattern, and unstable region with surface waves

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A JOURNEY FROM IB PRIMARY YEARS PROGRAMME TO MIDDLE YEARS PROGRAMME: TRANSITION AND ALIGNMENT IN THE SCIENCE CONTEXT

In International Baccalaureate programme, the transition from the Primary Years Programme to Middle Years Programme is associated with various complex challenges which often results in poor science academic performance of middle year students. These challenges can be attributed from more than one area, such as from students, teachers and from curriculum perspective. To reduce the challenges, transition strategies were designed and piloted such as the demonstration and experimentation. The demonstration helped to align the students understanding of some scientific terminologies while the experimentation was conducted to introduce the simplified lab report design that provided the students with basic knowledge on the experimental processes in the Middle Years and guided the students on the consistent use of the Modern Language Association format of referencing. This article evaluates various transition strategies which were found effective to aid the middle year students during the transition stage.  Article visualizations

ICT in Student-Supervisor Communication: A Case Study at a Public Institution of Higher Learning in Malaysia

This study examined the use of ICT among postgraduate students and supervisors at University of Science Malaysia, Penang with special focus on student-supervisor communication. It employed a cross sectional survey design utilising an online questionnaire as data collection instrument. Students' and supervisors' competence in using the common MS Office programs, data analysis packages, and communication tools were gauged. Apart from that, their perceptions on the usefulness of ICT in student-supervisor communication were measured according to the following aspects: improves communication; strengthen student-supervisor relationship; add value to face to face interaction; and optimize student learning. A total of 81 students and 70 supervisors participated in this study. The results show that both students and supervisors were either intermediate or advance users as far as the basic Microsoft Office programs are concerned but not many of them have good knowledge on other programs such as data analysis packages. As for the open source applications, significantly higher percentage of supervisors (76%) use Moodle compared to students (42%), however the percentage of student users were significantly higher for Wiki, Facebook, Blog, and Friendster. All supervisors and students surveyed used email as the major communication tool, while considerable percentage of supervisors (64.3%) and students (79%) used SMS. On the perception towards the usefulness of ICT, the supervisors' ratings range from 4.32 to 5.44 on a scale of 1 to 7. The highest rating was for all "ICT improves communication" while the lowest was "ICT add value to face-to-face interaction". Female supervisors have a more favorable perception compared to male on all the four aspects assessed (p < 0.05). Supervisors with less then 10 years in USM gave significantly higher rating on the following aspects: "ICT improves communication" and "ICT optimizes students' learning", whilst students' ratings range from 4.84 (ICT add value to face to face interaction) to 5.55 (ICT improves communication). Students' demography did not have any bearing on their ratings. The t-test analysis indicated that supervisors' and students' ratings on the usefulness of ICT significantly differed only for "ICT strengthen student-supervisor relationship" aspect (p = 0.021); students' rating was higher than the supervisors