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Physical Sciences and Mathematics Commons

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Physics

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Selected Works

Nicholas Whiting

2014

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Comparative Study Of In Situ N2 Rotational Raman Spectroscopy Methods For Probing Energy Thermalisation Processes During Spin-Exchange Optical Pumping, Hayley Newton, Laura L. Walkup, Nicholas Whiting, Linda West, James Carriere, Frank Havermeyer, Lawrence Ho, Peter Morris, Boyd M. Goodson, Michael J. Barlow Apr 2014

Comparative Study Of In Situ N2 Rotational Raman Spectroscopy Methods For Probing Energy Thermalisation Processes During Spin-Exchange Optical Pumping, Hayley Newton, Laura L. Walkup, Nicholas Whiting, Linda West, James Carriere, Frank Havermeyer, Lawrence Ho, Peter Morris, Boyd M. Goodson, Michael J. Barlow

Nicholas Whiting

Spin-exchange optical pumping (SEOP) has been widely used to produce enhancements in nuclear spin polarisation for hyperpolarised noble gases. However, some key fundamental physical processes underlying SEOP remain poorly understood, particularly in regards to how pump laser energy absorbed during SEOP is thermalised, distributed and dissipated. This study uses in situ ultra-low frequency Raman spectroscopy to probe rotational temperatures of nitrogen buffer gas during optical pumping under conditions of high resonant laser flux and binary Xe/N2 gas mixtures. We compare two methods of collecting the Raman scattering signal from the SEOP cell: a conventional orthogonal arrangement combining intrinsic spatial filtering …


Xena: An Automated 'Open-Source' 129xe Hyperpolarizer For Clinical Use, Panayiotis Nikolaou, Aaron M. Coffey, Laura L. Walkup, Brogan M. Gust, Nicholas Whiting, Hayley Newton, Iga Muradyan, Mikayel Dabaghyan, Kaili Ranta, Gregory D. Moroz, Matthew S. Rosen, Samuel Patz, Michael J. Barlow, Eduard Y. Chekmenev, Boyd M. Goodson Dec 2013

Xena: An Automated 'Open-Source' 129xe Hyperpolarizer For Clinical Use, Panayiotis Nikolaou, Aaron M. Coffey, Laura L. Walkup, Brogan M. Gust, Nicholas Whiting, Hayley Newton, Iga Muradyan, Mikayel Dabaghyan, Kaili Ranta, Gregory D. Moroz, Matthew S. Rosen, Samuel Patz, Michael J. Barlow, Eduard Y. Chekmenev, Boyd M. Goodson

Nicholas Whiting

Here we provide a full report on the construction, components, and capabilities of our consortium’s “opensource”
large-scale (~1 L/h) 129Xe hyperpolarizer for clinical, pre-clinical, and materials NMR/MRI (Nikolaou et al., Proc. Natl. Acad. Sci. USA, 110, 14150 (2013)). The ‘hyperpolarizer’ is automated and built mostly of off-the-shelf components; moreover, it is designed to be cost-effective and installed in both research laboratories and clinical settings with materials costing less than $125,000. The device runs in the xenon-rich regime (up to 1800 Torr Xe in 0.5 L) in either stopped-flow or single-batch mode—making cryo-collection of the hyperpolarized gas unnecessary for many applications. …