Unlabelled: Although there is increasing literature on blind and visually impaired students in science, technology, engineering, and mathematics (STEM), there is a prevalent gap in the literature regarding STEM educators who are blind or visually impaired. This account aims to partially fill this gap by presenting the methodology and implementation of teaching by Dr. Mona Minkara, a blind bioengineering professor, as well as the tangible outcomes of this approach.
View Article and Find Full Text PDFThe ability to map out electrostatic potentials in materials is critical for the development and the design of nanoscale electronic and spintronic devices in modern industry. Electron holography has been an important tool for revealing electric and magnetic field distributions in microelectronics and magnetic-based memory devices, however, its utility is hindered by several practical constraints, such as charging artifacts and limitations in sensitivity and in field of view. In this article, we report electron-beam-induced-current (EBIC) and secondary-electron voltage-contrast (SE-VC) with an aberration-corrected electron probe in a transmission electron microscope (TEM), as complementary techniques to electron holography, to measure electric fields and surface potentials, respectively.
View Article and Find Full Text PDFThe ability to map out electrostatic potentials in materials is critical for the development and the design of nanoscale electronic and spintronic devices in modern industry. Electron holography has been an important tool for revealing electric and magnetic field distributions in microelectronics and magnetic-based memory devices, however, its utility is hindered by several practical constraints, such as charging artifacts and limitations in sensitivity and in field of view. In this article, we report electron-beam-induced-current (EBIC) and secondary-electron voltage-contrast (SE-VC) with an aberration-corrected electron probe in a transmission electron microscope (TEM), as complementary techniques to electron holography, to measure electric fields and surface potentials, respectively.
View Article and Find Full Text PDFWe have investigated the use of various morphologies, including nanoparticles, nanowires, and sea-urchins of TiO(2) as the semiconducting material used as components of dye-sensitized solar cells (DSSCs). Analysis of the solar cells under AM 1.5 solar irradiation reveals the superior performance of hydrothermally derived nanoparticles, by comparison with two readily available commercial nanoparticle materials, within the DSSC architecture.
View Article and Find Full Text PDFOne-dimensional (1D) nanostructures, such as nanowires, nanotubes, nanorods, and nanoribbons, have attracted significant attention stemming from the plethora of interesting size-dependent and, more importantly, structure-related properties resulting from confinement effects. In particular, the novel properties of 1D nanostructures of metals and metal oxides (binary and ternary) render them as prime candidates for a wide range of applications including the fabrication of nanoscale devices associated with solar cells, energy storage, fuel cells, molecular computing and information storage, medical imaging, diagnosis and detection, drug delivery, sensors and catalysis. Thus, it has been simultaneously necessary and critical to create synthetic protocols for the production of these materials which not only are reliable and reproducible, but also can generate compositionally pure, monodisperse, highly crystalline products of a desired 1D morphology.
View Article and Find Full Text PDFIn this work, VO2 nanorods have been initially generated as reactive nanoscale precursors to their subsequent conversion to large quantities of highly crystalline V2O3 with no detectable impurities. Structural changes in VO2, associated with the metallic-to-insulating transition from the monoclinic form to the rutile form, have been investigated and confirmed using X-ray diffraction and synchrotron data, showing that the structural transition is reversible and occurs at around 63 degrees C. When this VO2 one-dimensional sample was subsequently heated to 800 degrees C in a reducing atmosphere, it was successfully transformed into V2O3 with effective retention of its nanorod morphology.
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