Results 251 to 260 of about 340,303 (295)

Low-field and benchtop NMR

Journal of Magnetic Resonance, 2019
NMR started at low field. Important discoveries like the first observation of NMR in condensed matter, the spin echo, NMR for chemical analysis, Fourier NMR spectroscopy, 2D NMR spectroscopy and magnetic resonance imaging happened at field strengths considered low today.
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Perfusion Measurement with Low Field NMR

2023
<p>Blood perfusion is a fundamental parameter of tissue health and function. Measurements of blood perfusion are clinically used to assess the severity of strokes, tumors and other diseases. Nuclear Magnetic Resonance (NMR) is a common modality for these measurements, due to its flexibility, sensitivity and lack of ionising radiation.</p> ...
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Low field NMR investigations of methyl tunnelling

Physica B: Condensed Matter, 1994
Abstract Low-field dipole-dipole-driven NMR has been used to measure the ground state methyl tunnelling frequencies in dimethylmalonic acid ( ν t = 337 ± 3 kHz), 3-hexanone ( ν t = 210 ± 10 kHz) and 4-heptanone ( ν t = 495 ± 3 kHz).
P.M. Debenham, A.J. Horsewill, I.B.I. Tomsah, S. Clough   +3 more
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Proton Low‐Field NMR Measurements on Crackers

Journal of Food Science, 1994
ABSTRACT We have shown that the signal obtained for crackers (3.5% water content) by low resolution NMR method using the CPMG sequence, described the relaxation of the protons of fat. For water content up to 7.1% the water signal is not seen by a CPMG sequence, the water has therefore a very short spin‐spin relaxation time (T2 < 0 ...
PASCAL DESBOIS, DENIS LE BOTLAN
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Monitoring Starch Saccharification Using Low Field NMR

2005 Tampa, FL July 17-20, 2005, 2005
The present study is an attempt to develop a low field NMR based technique for fast analysis of enzymatic saccharification of corn starch. Experiments were first conducted on model samples containing pure starch and glucose to prove the hypothesis.
null Fu, null R., null Qi, null J., null Ruan, null R. and Chen, null Xiangyang Lin, null Xiaofei Ye, null Chris Doona and Tom Yang   +8 more
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ChemInform Abstract: NMR at Low Magnetic Fields

ChemInform, 2009
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Bernhard Bluemich, Federico Casanova, Stephan Appelt   +2 more
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Porosity Distributions in Carbonate Reservoirs Using Low-Field NMR

Journal of Canadian Petroleum Technology, 2002
Abstract Alberta contains significant deposits of oil and gas in carbonate formations. Carbonates tend to have fairly tight matrix structures, resulting in low primary porosity and permeability. Laboratory characterization of carbonate properties is a slow and tedious process, however, core data is often collected ...
A. Mai, A. Kantzas
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A resistive Q-switch for low-field NMR systems

Journal of Magnetic Resonance, 2018
An NMR Q-switch was designed and constructed specifically for use with low-field NMR apparatus. This featured a comparatively simple resistive damping design. It served to reduce the r.f. probe ring-down time, and hence reduced the signal acquisition delay from 25 ms to 9 ms, on an Earth's magnetic field NMR system.
J Z, Zhen, K T, O'Neill, E O, Fridjonsson, P L, Stanwix, M L, Johns   +4 more
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Differentiation of fentanyl analogues by low-field NMR spectroscopy

Analytica Chimica Acta, 2019
Forensic laboratories commonly receive new psychoactive substances such as fentanyl analogues and other synthetic opioids that are difficult to identify. Slight changes to chemical structures, e.g. shifting the position of functional groups such as methyl groups or halogens on the aromatic ring, may not be distinguished using traditional methods.
Jonathan Duffy, Aaron Urbas, Matthias Niemitz, Katrice Lippa, Ioan Marginean   +4 more
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Optical Atomic Magnetometry for Ultra-Low-Field NMR Detection

2013
Abstract This chapter deals with detection of nuclear magnetic resonance (NMR) signals in the ultra-low-field (ULF) regime, by means of optical atomic magnetometers (OAMs). A general introduction is provided about specific NMR features occurring when nuclei precess in microtesla fields, or weaker.
BEVILACQUA, GIUSEPPE, BIANCALANA, VALERIO, DANCHEVA, YORDANKA, MOI, LUIGI   +3 more
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