Marcus D Lay

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Single-walled carbon nanotubes (SWNTs) have become one of the most intensely studied nanostructures because of their unique properties. The inherent physical properties of carbon nanotubes make them ideal supports for metal nanoparticles. The use of electrodeposition to modify SWNTs in order to facilitate applications in areas related to catalysis and(More)
Single-walled carbon nanotubes (SWNTs) have had significant impact on the development of gas sensors in the last decade. However, useful applications of SWNTs are limited by the lack of manufacturable routes to device formation. This Highlight article chronicles recent progress in this area and demonstrates the great promise of a new room temperature(More)
Ge nanofilms were deposited from aqueous solutions using the electrochemical analog of atomic layer deposition (ALD). Direct electrodeposition of Ge from an aqueous solution is self-limited to a few monolayers, depending on the pH. This report describes an E-ALD process for the growth of Ge films from aqueous solutions. The E-ALD cycle involved inducing a(More)
Due to their extreme sensitivity to surface adsorption events, there has been great interest in incorporating single walled carbon nanotubes (SWNTs) into sensing devices. However, a practical sensor needs to have selective response in addition to sensitivity. Therefore, recent efforts have focused on efforts to increase selectivity in SWNT sensors. This(More)
All of the Monte Carlo codes currently available for SNO use EGS4 to propagate the electrons and gammas created by neutrino interactions. It is therefore important to demonstrate that the EGS4 code performs this task correctly, specifically that EGS4 (as modified by the collaboration to produce Cerenkov radiation) produces the proper number and angular(More)
EGS4 contains a number of non-physical parameters introduced to allow the modelling of various physical processes; the most usually discussed are ESTEPE, the parameter that controls the maximum allowable step length, and AE, the parameter that defines the calculational boundary between discrete interactions and continuous energy loss for electrons. In this(More)
We report on attempts to construct and simulate low intensity sources of Cerenkov radiation with accurately known spectral intensity. These sources will be used to calibrate photomultipliers for the Sudbury Neutrino Observatory. We have used ^Sr as a radioactive beta source located at the center of a sphere of ultraviolet transparent acrylic. The production(More)
Aqueous batch processing methods for the concurrent purification of single-walled carbon nanotube (SWNT) soot and enrichment in high aspect ratio nanotubes are essential to their use in a wide variety of electronic, structural, and mechanical applications. This manuscript presents a new route to the bulk purification and enrichment of unbundled SWNTs having(More)
This paper describes measurements made on Hamamatsu R1408 8-m. photomultiplier tubes in order to parameterise the cesium bialkali photocathode in terms of a complex refractive index fi and a thickness T. The extracted parameters have been used to predict the angular response of the photomultiplier tubes, and this prediction has been experimentally verified.(More)