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We report on electric field effects on electron transport in multi-walled MoS2 nanotubes (NTs), fabricated using a two-step synthesis method from Mo6SxI9-x nanowire bundle precursors. Transport properties were measured on 20 single nanotube field effect transistor (FET) devices, and compared with MoS2 layered crystal devices prepared using identical fabrication techniques. The NTs exhibited mobilities of up to 0.014 cm²V-1s-1 and an on/off ratio of up to 60. As such they are comparable with previously reported WS2 nanotube FETs, but materials defects and imperfections apparently limit their performance compared with multilayer MoS2 FETs with similar number of layers. [ABSTRACT FROM AUTHOR]

Highlights: [•] Determination of exact time of combustion start. [•] Visualization of spark-plug creation and its trajectory. [•] Visualization of direction of combustion propagation 0.5ms after start. [•] Flow visualization of combustion-consumed by-products. [•] Identification of heat flow in combustion process. [Copyright &y& Elsevier]

Abstract: Sample temperature may theoretically be determined if we know or measure four quantities (two radiances at two specific wavelengths). We performed differential, continuous two-wavelength thermometry on a micro-surface element of the coiled coil filament used in tungsten lamp with a spectrometer. Results indicate that differential, continuous thermometry using a spectrometer measures temperature distribution along a short line. This method significantly enhances the capability of this established technique to new applications. [Copyright &y& Elsevier]

The application of a positive or negative local bias to the surface of La1.975Sr0.025CuO4+δ (LSCO) crystal by a conducting atomic force microscope tip results in accumulation of a (positive or negative, respectively) metastable charge on the surface. The surface charge initially shows diffusive dynamics with a timescale of hours, but thereafter it is shown to be stable for months. The charged regions are found by Auger electron spectroscopy to have a different stoichiometry from the surrounding material. Apart from fundamental implications for the heterostructure device construction, such surface charge manipulation could lead to AFM nanopatterning of superconducting nanoscale devices and applications in memories. [ABSTRACT FROM AUTHOR]

Abstract: The interferometric intensity patterns from a 2D shearing interferometer are shown and discussed. The intensity patterns can be obtained in two different approaches incorporating differential and extended wavefront controlled displacements. The reliable directional sensitivity of this interferometer allows the optimization of the measurement parameters to estimate the wavefront of the intensity patterns by regularization techniques. [Copyright &y& Elsevier]