Novel hardware for temperature-jump DNP
Although NMR is a versatile technique, the low values associated with nuclear spin polarization provide inherently weak signals. A novel system to perform temperature-jump dynamic nuclear polarization (DNP) has been designed and developed at the University of Nottingham, with the aim to enhance this...
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| Format: | Thesis (University of Nottingham only) |
| Language: | English |
| Published: |
2018
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| Online Access: | https://eprints.nottingham.ac.uk/52518/ |
| _version_ | 1848798744232853504 |
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| author | Breeds, Edward |
| author_facet | Breeds, Edward |
| author_sort | Breeds, Edward |
| building | Nottingham Research Data Repository |
| collection | Online Access |
| description | Although NMR is a versatile technique, the low values associated with nuclear spin polarization provide inherently weak signals. A novel system to perform temperature-jump dynamic nuclear polarization (DNP) has been designed and developed at the University of Nottingham, with the aim to enhance this signal and improve the sensitivity of the NMR experiment.
This system utilizes a bespoke helium flow cryostat, located within the bore of a superconducting magnet, to achieve temperatures down to 1.75 K for high levels of polarization to build up on an electron spin population. This high level of polarization can then be transferred to a nuclear species of interest using microwave irradiation, while remaining at low temperature, allowing the weak signals associated with NMR to become enhanced. Following ample nuclear polarization build-up, a powerful mid-IR laser is used to rapidly bring the sample to 300 K, ensuring the spectra benefit from the line narrowing associated with liquid-state NMR. An Er:YAG laser with a wavelength of 2.94 µm has been chosen for this as it couples energy directly into the vibrational modes of hydroxyl groups present within the sample.
The rapid heating mechanism underpins the success of this experiment twofold. Firstly, performing the temperature-jump in a shorter time period preserves a greater signal enhancement. This needs to be done carefully as too much heating will obliterate the sample, destroying the signal. Secondly, a temperature-jump without dilution of the sample, as occurs in dissolution DNP, allows sample recycling to take place. This opens the technique up for otherwise unavailable applications, such as multidimensional correlation spectroscopy with repetitive excitations. Development of the cryo-system, heating mechanism and NMR probe, alongside preliminary experiments and calculations, suggest that this technique should greatly improve the sensitivity of the liquid state NMR experiment. |
| first_indexed | 2025-11-14T20:24:38Z |
| format | Thesis (University of Nottingham only) |
| id | nottingham-52518 |
| institution | University of Nottingham Malaysia Campus |
| institution_category | Local University |
| language | English |
| last_indexed | 2025-11-14T20:24:38Z |
| publishDate | 2018 |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | nottingham-525182025-02-28T12:06:10Z https://eprints.nottingham.ac.uk/52518/ Novel hardware for temperature-jump DNP Breeds, Edward Although NMR is a versatile technique, the low values associated with nuclear spin polarization provide inherently weak signals. A novel system to perform temperature-jump dynamic nuclear polarization (DNP) has been designed and developed at the University of Nottingham, with the aim to enhance this signal and improve the sensitivity of the NMR experiment. This system utilizes a bespoke helium flow cryostat, located within the bore of a superconducting magnet, to achieve temperatures down to 1.75 K for high levels of polarization to build up on an electron spin population. This high level of polarization can then be transferred to a nuclear species of interest using microwave irradiation, while remaining at low temperature, allowing the weak signals associated with NMR to become enhanced. Following ample nuclear polarization build-up, a powerful mid-IR laser is used to rapidly bring the sample to 300 K, ensuring the spectra benefit from the line narrowing associated with liquid-state NMR. An Er:YAG laser with a wavelength of 2.94 µm has been chosen for this as it couples energy directly into the vibrational modes of hydroxyl groups present within the sample. The rapid heating mechanism underpins the success of this experiment twofold. Firstly, performing the temperature-jump in a shorter time period preserves a greater signal enhancement. This needs to be done carefully as too much heating will obliterate the sample, destroying the signal. Secondly, a temperature-jump without dilution of the sample, as occurs in dissolution DNP, allows sample recycling to take place. This opens the technique up for otherwise unavailable applications, such as multidimensional correlation spectroscopy with repetitive excitations. Development of the cryo-system, heating mechanism and NMR probe, alongside preliminary experiments and calculations, suggest that this technique should greatly improve the sensitivity of the liquid state NMR experiment. 2018-07-19 Thesis (University of Nottingham only) NonPeerReviewed application/pdf en arr https://eprints.nottingham.ac.uk/52518/1/Novel%20Hardware%20for%20Temperature-Jump%20DNP.pdf Breeds, Edward (2018) Novel hardware for temperature-jump DNP. PhD thesis, University of Nottingham. NMR DNP TJ-DNP Temperature-Jump DNP Nottingham |
| spellingShingle | NMR DNP TJ-DNP Temperature-Jump DNP Nottingham Breeds, Edward Novel hardware for temperature-jump DNP |
| title | Novel hardware for temperature-jump DNP |
| title_full | Novel hardware for temperature-jump DNP |
| title_fullStr | Novel hardware for temperature-jump DNP |
| title_full_unstemmed | Novel hardware for temperature-jump DNP |
| title_short | Novel hardware for temperature-jump DNP |
| title_sort | novel hardware for temperature-jump dnp |
| topic | NMR DNP TJ-DNP Temperature-Jump DNP Nottingham |
| url | https://eprints.nottingham.ac.uk/52518/ |