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Journal articles on the topic 'NMR spectrometers'

To see the other types of publications on this topic, follow the link: NMR spectrometers.

Author: Grafiati

Published: 4 June 2021

Last updated: 19 February 2022

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1

Chakrapani, Sneha B., Michael J. Minkler, and Bryan S. Beckingham. "Low-field 1H-NMR spectroscopy for compositional analysis of multicomponent polymer systems." Analyst 144, no. 5 (2019): 1679–86. http://dx.doi.org/10.1039/c8an01810c.

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2

Gomes, Bruna, Carlos Lobo, and Luiz Colnago. "Monitoring Electrochemical Reactions in Situ with Low Field NMR: A Mini-Review." Applied Sciences 9, no. 3 (February 1, 2019): 498. http://dx.doi.org/10.3390/app9030498.

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The number of applications of time domain NMR using low-field spectrometers in research and development has been steadily increasing in recent years with applications ranging from quality control of industrial products to the study of physical and chemical properties of a wide array of solid and liquid samples to, most recently, electrochemical studies. In this mini-review we summarize the progress that has been achieved in the coupling between time domain NMR (using low-field spectrometers) and electrochemistry and how the challenges that this coupling poses have been overcome over the years. We also highlight the effect that the static magnetic field of the NMR spectrometer has on the electrochemical systems.

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3

Akay, Cengiz, and Aytaç Yalçiner. "A New Weak Field Double Resonance NMR Spectrometer." Zeitschrift für Naturforschung A 50, no. 2-3 (March 1, 1995): 177–85. http://dx.doi.org/10.1515/zna-1995-2-309.

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Abstract Weak field NMR and double resonance spectrometers are mostly homemade. In this work, some electronic units of such a spectrometer operating at 1.437 mT were designed and realized by including new integrated circuits: an audio generator, digital sweep generator, digital additional field and delay unit, Quartz generator, NMR detector(Q-meter), AF-narrowband amplifier, phase shifter and phase sensitive detector.

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4

Riegel, Susanne D., and Garett M. Leskowitz. "Benchtop NMR spectrometers in academic teaching." TrAC Trends in Analytical Chemistry 83 (October 2016): 27–38. http://dx.doi.org/10.1016/j.trac.2016.01.001.

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5

Lilly, Kevi. "5534780 Sample changer for NMR spectrometers." Magnetic Resonance Imaging 15, no. 3 (January 1997): XX. http://dx.doi.org/10.1016/s0730-725x(97)82890-1.

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6

Danieli, Ernesto, Juan Perlo, Bernhard Blümich, and Federico Casanova. "Small Magnets for Portable NMR Spectrometers." Angewandte Chemie International Edition 49, no. 24 (May 5, 2010): 4133–35. http://dx.doi.org/10.1002/anie.201000221.

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7

Jonsen, Paul. "5036279 Portable NMR and NQR spectrometers." Magnetic Resonance Imaging 11, no. 2 (January 1993): V. http://dx.doi.org/10.1016/0730-725x(93)90057-k.

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8

van Os, J. W. M., G. J. W. Steeg, and W. S. Veeman. "Direct digital frequency modulation in NMR spectrometers." Review of Scientific Instruments 62, no. 5 (May 1991): 1285–87. http://dx.doi.org/10.1063/1.1142486.

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9

Cosgrove, T., S. Neck, and N. A. Finch. "A simple phase shifter for NMR spectrometers." Journal of Magnetic Resonance (1969) 62, no. 2 (April 1985): 309–10. http://dx.doi.org/10.1016/0022-2364(85)90064-2.

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10

Rachineni, Kavitha, Veera Mohana Rao Kakita, and Ramakrishna V. Hosur. "Ultra-high resolution in low field tabletop NMR spectrometers." RSC Adv. 7, no. 77 (2017): 49102–4. http://dx.doi.org/10.1039/c7ra09594e.

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An approach for resolution enhancement is proposed, for data acquired on low field tabletop NMR spectrometers by employing processing-based (generalized indirect covariance) advancements in pure shift NMR.

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11

Kudyakova, V., and A. Chazov. "COMPREHENSIVE NMR ANALYSIS ON YOUR DESKTOP: SPINSOLVE BENCHTOP NMR SPECTROMETERS BY MAGRITEK." Analytics, no. 2 (2017): 80–83. http://dx.doi.org/10.22184/2227-572x.2017.33.2.80.83.

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12

Vallet, Alicia, Adrien Favier, Bernhard Brutscher, and Paul Schanda. "ssNMRlib: a comprehensive library and tool box for acquisition of solid-state nuclear magnetic resonance experiments on Bruker spectrometers." Magnetic Resonance 1, no. 2 (December 23, 2020): 331–45. http://dx.doi.org/10.5194/mr-1-331-2020.

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Abstract. We introduce ssNMRlib, a comprehensive suite of pulse sequences and jython scripts for user-friendly solid-state nuclear magnetic resonance (NMR) data acquisition, parameter optimization and storage on Bruker spectrometers. ssNMRlib allows the straightforward setup of even highly complex multi-dimensional solid-state NMR experiments with a few clicks from an intuitive graphical interface directly from the Bruker Topspin acquisition software. ssNMRlib allows the setup of experiments in a magnetic-field-independent manner and thus facilitates the workflow in a multi-spectrometer setting with a centralized library. Safety checks furthermore assist the user in experiment setup. Currently hosting more than 140 1D to 4D experiments, primarily for biomolecular solid-state NMR, the library can be easily customized and new experiments are readily added as new templates. ssNMRlib is part of the previously introduced NMRlib library, which comprises many solution-NMR pulse sequences and macros.

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13

Kernevez, N., D. Duret, M. Moussavi, and J. M. Leger. "Weak field NMR and ESR spectrometers and magnetometers." IEEE Transactions on Magnetics 28, no. 5 (September 1992): 3054–59. http://dx.doi.org/10.1109/20.179715.

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14

Schwalbe, Harald. "Editorial: New 1.2 GHz NMR Spectrometers- New Horizons?" Angewandte Chemie International Edition 56, no. 35 (July 24, 2017): 10252–53. http://dx.doi.org/10.1002/anie.201705936.

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15

Marek, Daniel. "5247256 RF receiver coil arrangement for NMR spectrometers." Magnetic Resonance Imaging 12, no. 5 (January 1994): XIX. http://dx.doi.org/10.1016/0730-725x(94)92275-6.

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16

Parbhoo, Bhukan. "A new standard performance test for NMR spectrometers." Journal of Magnetic Resonance (1969) 87, no. 2 (April 1990): 372–74. http://dx.doi.org/10.1016/0022-2364(90)90014-z.

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17

Smernik, Ronald J., Eileen Eckmeier, and Michael W. I. Schmidt. "Comparison of solid-state 13C NMR spectra of soil organic matter from an experimental burning site acquired at two field strengths." Soil Research 46, no. 2 (2008): 122. http://dx.doi.org/10.1071/sr07128.

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Solid-state 13C cross polarisation (CP) nuclear magnetic resonance spectra were acquired for 15 soil organic matter samples on 2 different spectrometers (200 MHz and 400 MHz). Distributions of broad functional group classes—carboxyl, aryl, O-alkyl, and alkyl—were determined by integration across broad chemical shift regions. The distributions derived from the 2 spectrometers were closely correlated (r2 = 0.77–0.93). Only slight biases were identified; carboxyl C contents were on average 8% lower and alkyl C contents 5% higher for spectra acquired on the 400 MHz spectrometer. These results indicate that valid 13C CP spectra can be acquired at field strengths up to 400 MHz, and that spectra acquired at different field strengths can be directly comparable.

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18

Percival, Benita C., Martin Grootveld, Miles Gibson, Yasan Osman, Marco Molinari, Fereshteh Jafari, Tarsem Sahota, et al. "Low-Field, Benchtop NMR Spectroscopy as a Potential Tool for Point-of-Care Diagnostics of Metabolic Conditions: Validation, Protocols and Computational Models." High-Throughput 8, no. 1 (December 27, 2018): 2. http://dx.doi.org/10.3390/ht8010002.

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Novel sensing technologies for liquid biopsies offer promising prospects for the early detection of metabolic conditions through omics techniques. Indeed, high-field nuclear magnetic resonance (NMR) facilities are routinely used for metabolomics investigations on a range of biofluids in order to rapidly recognise unusual metabolic patterns in patients suffering from a range of diseases. However, these techniques are restricted by the prohibitively large size and cost of such facilities, suggesting a possible role for smaller, low-field NMR instruments in biofluid analysis. Herein we describe selected biomolecule validation on a low-field benchtop NMR spectrometer (60 MHz), and present an associated protocol for the analysis of biofluids on compact NMR instruments. We successfully detect common markers of diabetic control at low-to-medium concentrations through optimised experiments, including α-glucose (≤2.8 mmol/L) and acetone (25 µmol/L), and additionally in readily accessible biofluids, particularly human urine. We present a combined protocol for the analysis of these biofluids with low-field NMR spectrometers for metabolomics applications, and offer a perspective on the future of this technique appealing to ‘point-of-care’ applications.

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19

Barbosa, T. M., R. Rittner, C. F. Tormena, G. A. Morris, and M. Nilsson. "Convection in liquid-state NMR: expect the unexpected." RSC Advances 6, no. 97 (2016): 95173–76. http://dx.doi.org/10.1039/c6ra23427e.

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Temperature gradients in liquid NMR samples cause convection, attenuating signals in experiments that use field gradients. Different spectrometers and probes show surprisingly different dependences of convection velocity v_max on temperature T.

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20

Hearmon, R. Angus, and John Goodacre. "Waltz-16 decoupling on JEOL FX series NMR spectrometers." Magnetic Resonance in Chemistry 24, no. 3 (March 1986): 259–62. http://dx.doi.org/10.1002/mrc.1260240315.

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21

Dereppe, J. M., X. Lemercinier, C. Moreaux, and H. Haut. "NMR Imaging Machine Using Components of Commercial HR Spectrometers." Bulletin des Sociétés Chimiques Belges 94, no. 11-12 (September 1, 2010): 777–83. http://dx.doi.org/10.1002/bscb.19850941103.

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22

Kiyoshi, T., H. Maeda, J. Kikuchi, Y. Ito, H. Hirota, S. Yokoyama, S. Ito, et al. "Present Status of 920 MHz High-Resolution NMR Spectrometers." IEEE Transactions on Appiled Superconductivity 14, no. 2 (June 2004): 1608–12. http://dx.doi.org/10.1109/tasc.2004.831010.

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23

Lee, Woonghee, Kaifeng Hu, Marco Tonelli, Arash Bahrami, Elizabeth Neuhardt, Karen C. Glass, and John L. Markley. "Fast automated protein NMR data collection and assignment by ADAPT-NMR on Bruker spectrometers." Journal of Magnetic Resonance 236 (November 2013): 83–88. http://dx.doi.org/10.1016/j.jmr.2013.08.010.

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24

Moyna, G., J. Cernadas, L. Mussio, and G. Hernandez. "Implementation of Fourier transform rapid scan NMR spectroscopy techniques in continuous wave NMR spectrometers." Journal of Chemical Education 70, no. 12 (December 1993): A314. http://dx.doi.org/10.1021/ed070pa314.

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25

Richardson, Peter M., Andrew J. Parrott, Olga Semenova, Alison Nordon, Simon B. Duckett, and Meghan E. Halse. "SABRE hyperpolarization enables high-sensitivity 1H and 13C benchtop NMR spectroscopy." Analyst 143, no. 14 (2018): 3442–50. http://dx.doi.org/10.1039/c8an00596f.

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Benchtop NMR spectrometers operating with magnetic fields of 1–2 T at sub-ppm resolution coupled with SABRE hyperpolarization show great promise as analytical platforms that can be used outside the traditional laboratory environment.

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26

Yu, Hyo-Yeon, Sangki Myoung, and Sangdoo Ahn. "Recent Applications of Benchtop Nuclear Magnetic Resonance Spectroscopy." Magnetochemistry 7, no. 9 (September 1, 2021): 121. http://dx.doi.org/10.3390/magnetochemistry7090121.

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Benchtop nuclear magnetic resonance (NMR) spectroscopy uses small permanent magnets to generate magnetic fields and therefore offers the advantages of operational simplicity and reasonable cost, presenting a viable alternative to high-field NMR spectroscopy. In particular, the use of benchtop NMR spectroscopy for rapid in-field analysis, e.g., for quality control or forensic science purposes, has attracted considerable attention. As benchtop NMR spectrometers are sufficiently compact to be operated in a fume hood, they can be efficiently used for real-time reaction and process monitoring. This review introduces the recent applications of benchtop NMR spectroscopy in diverse fields, including food science, pharmaceuticals, process and reaction monitoring, metabolomics, and polymer materials.

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27

Leenders, Justine, Martin Grootveld, Benita Percival, Miles Gibson, Federico Casanova, and Philippe B. Wilson. "Benchtop Low-Frequency 60 MHz NMR Analysis of Urine: A Comparative Metabolomics Investigation." Metabolites 10, no. 4 (April 16, 2020): 155. http://dx.doi.org/10.3390/metabo10040155.

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Metabolomics techniques are now applied in numerous fields, with the ability to provide information concerning a large number of metabolites from a single sample in a short timeframe. Although high-frequency (HF) nuclear magnetic resonance (NMR) analysis represents a common method of choice to perform such studies, few investigations employing low-frequency (LF) NMR spectrometers have yet been published. Herein, we apply and contrast LF and HF 1H-NMR metabolomics approaches to the study of urine samples collected from type 2 diabetic patients (T2D), and apply a comparative investigation with healthy controls. Additionally, we explore the capabilities of LF 1H-1H 2D correlation spectroscopy (COSY) experiments regarding the determination of metabolites, their resolution and associated analyses in human urine samples. T2D samples were readily distinguishable from controls, with several metabolites, particularly glucose, being associated with this distinction. Comparable results were obtained with HF and LF spectrometers. Linear correlation analyses were performed to derive relationships between the intensities of 1D and 2D resonances of several metabolites, and R2 values obtained were able to confirm these, an observation attesting to the validity of employing 2D LF experiments for future applications in metabolomics studies. Our data suggest that LF spectrometers may prove to be easy-to-use, compact and inexpensive tools to perform routine metabolomics analyses in laboratories and ‘point-of-care’ sites. Furthermore, the quality of 2D spectra obtained from these instruments in half an hour would broaden the horizon of their potential applications.

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28

Price, William S. "Recent Advances in NMR Diffusion Techniques for Studying Drug Binding." Australian Journal of Chemistry 56, no. 9 (2003): 855. http://dx.doi.org/10.1071/ch03128.

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Characterizing the binding of ligands to macromolecular receptors in solution is important to many areas of chemistry, biology, and nanobiotechnology, but perhaps most notably to drug development. NMR has proven to be particularly useful for such studies, but the systems studied have generally been restricted to model systems with dubious physiological relevance. This paper reviews the use of NMR diffusion measurements to study drug binding and two recent advances that enable measurements to be conducted in more sensitive higher-field NMR spectrometers in non-deuterated aqueous samples.

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29

Loening, Nikolaus M., and James Keeler. "Temperature accuracy and temperature gradients in solution-state NMR spectrometers." Journal of Magnetic Resonance 159, no. 1 (November 2002): 55–61. http://dx.doi.org/10.1016/s1090-7807(02)00120-9.

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30

Favier, Adrien, and Bernhard Brutscher. "NMRlib: user-friendly pulse sequence tools for Bruker NMR spectrometers." Journal of Biomolecular NMR 73, no. 5 (May 2019): 199–211. http://dx.doi.org/10.1007/s10858-019-00249-1.

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31

Wiggershaus-Eschert, Sabine, Inge Wieschenk�mper, and Wolfgang Riepe. "Quantitative 13C-NMR spectroscopy of coals using 200 MHz-spectrometers." Fresenius' Journal of Analytical Chemistry 346, no. 6-9 (1993): 805–7. http://dx.doi.org/10.1007/bf00321294.

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32

Laurent, G., and M. Guéron. "Design and Implementation of a Protection System for NMR Spectrometers." Journal of Magnetic Resonance 156, no. 2 (June 2002): 295–302. http://dx.doi.org/10.1006/jmre.2002.2558.

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33

Utomo, Suryadi Budi, Jumina Jumina, Dwi Siswanta, Mustofa Mustofa, and Naresh Kumar. "SYNTHESIS OF THIOMETHYLATED CALIX[4]RESORCINARENE BASED ON FENNEL OIL VIA CHLOROMETHYLATION." Indonesian Journal of Chemistry 11, no. 1 (July 12, 2011): 1–8. http://dx.doi.org/10.22146/ijc.21411.

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A research has been conducted to synthesize thiomethylated-C-4-methoxyphenylcalix[4]resorcinarene using fennel oil as a starting material. The synthesis was carried out in four steps i.e. (1) oxidation of anethole to yield p-anisaldehyde, (2) HCl-catalyzed condensation of p-anisaldehyde with resorcinol, (3) chloromethylation of C-4-methoxyphenylcalix[4]resorcinarene with paraformaldehyde and HCl in the presence of ZnCl2 to yield tetrakis-chloromethyl-C-4-methoxyphenylcalix[4]resorcinarene, and (4) reaction of tetrakis-chloromethyl-C-4-methoxyphenylcalix[4]resorcinarene with thiourea followed by hydrolysis with sodium hydroxide solution to yield tetrakis-thiomethyl-C-4-methoxyphenylcalix[4]resorcinarene. The prepared compounds were characterized based on melting point, FT-IR, and NMR spectrometers. According to the analysis of 1H-NMR spectrometer, C-4-methoxyphenylcalix[4]resorcinarene and tetrakis-chloromethyl-C-4-methoxyphenylcalix[4]resorcinarene were observed in the chair or flattened partial cone conformation, while tetrakis-thiomethyl-C-4-methoxyphenylcalix[4]resorcinarene tend to exist in the crown or cone conformation.

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34

Koskela, Harri, Outi Heikkilä, Ilkka Kilpeläinen, and Sami Heikkinen. "Quantitative two-dimensional HSQC experiment for high magnetic field NMR spectrometers." Journal of Magnetic Resonance 202, no. 1 (January 2010): 24–33. http://dx.doi.org/10.1016/j.jmr.2009.09.021.

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35

Vandoren, S. R., and E. R. P. Zuiderweg. "An Auxiliary RF Channel with Convenient Phase Control for NMR Spectrometers." Journal of Magnetic Resonance, Series A 104, no. 2 (September 1993): 222–25. http://dx.doi.org/10.1006/jmra.1993.1213.

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36

Field, Leslie D., and Alan K. Mcphail. "Heteronuclear pulse with proton observation on bruker WM-400 NMR spectrometers." Journal of Magnetic Resonance (1969) 67, no. 2 (April 1986): 364–66. http://dx.doi.org/10.1016/0022-2364(86)90444-0.

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37

Zhurenko, S. V., A. V. Tkachev, A. V. Gunbin, and A. A. Gippius. "Upgrade of a Bruker NMR Spectrometers Using a Modern Digital Base." Instruments and Experimental Techniques 64, no. 3 (May 2021): 427–33. http://dx.doi.org/10.1134/s0020441221020202.

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38

Bain, Alex D., Brian J. Fahie, Tomasz Kozluk, and William J. Leigh. "Improvements in the quantitation of NMR spectra by the use of statistical methods." Canadian Journal of Chemistry 69, no. 8 (August 1, 1991): 1189–92. http://dx.doi.org/10.1139/v91-177.

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In many applications of NMR spectroscopy to chemistry, quantitation play s a key role. This paper argues that peak heights not only can be used for quantitative work in NMR but that for careful work they should be used. Integrals are accurate, but because they depend on many subjective factors, their precision is suspect. Peak heights are very reproducible on modern spectrometers and so, given this precision, the accuracy can be obtained as well by using calibration methods. An example of the application of these methods is given in the case of a 13C labelling experiment that elucidates a photochemical transformation. Key words: NMR, labelling, quantitation, peak heights, integrals.

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39

Robinson, Alastair, Peter Richardson, and Meghan Halse. "Hyperpolarised 1H–13C Benchtop NMR Spectroscopy." Applied Sciences 9, no. 6 (March 20, 2019): 1173. http://dx.doi.org/10.3390/app9061173.

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Benchtop NMR spectrometers with sub-ppm spectral resolution have opened up new opportunities for performing NMR outside of the standard laboratory environment. However, the relatively weak magnetic fields of these devices (1–2 T) results in low sensitivity and significant peak overlap in 1H NMR spectra. Here, we use hyperpolarised 13C{1H} NMR to overcome these challenges. Specifically, we demonstrate the use of the signal amplification by reversible exchange (SABRE) parahydrogen-based hyperpolarisation technique to enhance the sensitivity of natural abundance 1D and 2D 13C{1H} benchtop NMR spectra. We compare two detection methods for SABRE-enhanced 13C NMR and observe an optimal 13C{1H} signal-to-noise ratio (SNR) for a refocused INEPT approach, where hyperpolarisation is transferred from 1H to 13C. In addition, we exemplify SABRE-enhanced 2D 13C benchtop NMR through the acquisition of a 2D HETCOR spectrum of 260 mM of 4-methylpyridine at natural isotopic abundance in a total experiment time of 69 min. In theory, signal averaging for over 300 days would be required to achieve a comparable SNR for a thermally polarised benchtop NMR spectrum acquired of a sample of the same concentration at natural abundance.

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40

De Carvalho, Gustavo Senra Gonçalves, Álisson Silva Granato, Pedro Pôssa De Castro, and Giovanni Wilson Amarante. "Recent Contributions of Nuclear Magnetic Resonance in Organocatalysis Mechanism Elucidation." Current Organocatalysis 7, no. 1 (December 12, 2019): 7–22. http://dx.doi.org/10.2174/2213337206666190328210907.

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Background: Nuclear Magnetic Resonance (NMR) is one of the most employed techniques in structural elucidation of organic compounds. In addition to its use in structural characterization, it has been widely employed in the investigation of reaction mechanisms, especially those involving catalysis. Objective: In this review, we aim to provide recent examples of the interface of NMR and organocatalysis reaction mechanism. Methods: Selected examples of different approaches for mechanism elucidation will be presented, such as isotopic effect, catalyst labelling and online reaction monitoring. A discussion involving the use of solid-state NMR will also be disclosed. Conclusion: NMR consists of a non-destructive technique, extremely useful in the real-time identification of intermediates in crude reaction mixtures. With the advent of two-dimensional experiments and high field NMR spectrometers, the reports of studies involving mechanistic elucidation were greatly enhanced. In this context, nowadays NMR appears as a powerful tool for the comprehension of reaction mechanisms, including the possibility of the proposal of unknown reaction mechanisms within organocatalysis.

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41

Bal, Dominika, Anna Kraska-Dziadecka, Wanda Gradowska, and Adam Gryff-Keller. "Investigation of a wide spectrum of inherited metabolic disorders by 13C NMR spectroscopy." Acta Biochimica Polonica 55, no. 1 (January 23, 2008): 107–18. http://dx.doi.org/10.18388/abp.2008_3103.

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High-resolution (1)H NMR spectroscopy of body fluids has proved to be very useful in diagnostics of inherited metabolic diseases, whereas (13)C NMR remains almost unexploited. In this paper the application of (13)C NMR spectroscopy of fivefold concentrated urine samples for diagnosis of selected metabolic diseases is reported. Various marker metabolites were identified in test urine samples from 33 patients suffering from 10 different diseases, providing information which could be crucial for their diagnoses. Spectra were accumulated for 2 h or overnight when using spectrometers operating at 9.4 or 4.7 T magnetic fields, respectively. Interpretation of the measurement results was based on a comparison of the peak positions in the measured spectrum with reference data. The paper contains a table with (13)C NMR chemical shifts of 73 standard compounds. The method can be applied individually or as an auxiliary technique to (1)H NMR or any other analytical method.

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42

Saleh, Fatemeh K., Catalin Teodoriu, and Carl Sondergeld. "Review of NMR Studies for Oilwell Cements and Their Importance." ChemEngineering 5, no. 2 (April 19, 2021): 18. http://dx.doi.org/10.3390/chemengineering5020018.

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This paper summarizes experimental studies using Nuclear Magnetic Resonance (NMR) to evaluate cement porosity, pore size distribution, and other characteristics such as Calcium Silicate Hydrate (CSH) gel structure and morphology. The first known paper on NMR experiments to investigate cement pastes was published in 1978. Two main NMR parameters, the so-called longitudinal T1 and transverse T2 relaxation times, are commonly measured and analyzed, representing the water response which is trapped in the cement. The hydration process reported in this paper was found to be monitored from as low as 10 min to longer than 365 days. Other studies conducted experiments by using NMR, especially during the 1980s. These studies employed variations in methodologies and frequencies, making data comparison difficult. Additionally, different spectrometers and NMR concepts, as well as operating characteristics, were used. Therefore, it is challenging to reconcile results from previous NMR studies on cement. Other significant hurdles are different cement types, water/cement ratio, and curing conditions. One notable observation is that there has not been any comprehensive laboratory work related to NMR on oilfield cement types, including porosity and hydration. Two recent studies have presented NMR measurements on class G and class H cements.

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43

Roehrl, Michael H. A., Gregory J. Heffron, and Gerhard Wagner. "Correspondence between spin-dynamic phases and pulse program phases of NMR spectrometers." Journal of Magnetic Resonance 174, no. 2 (June 2005): 325–30. http://dx.doi.org/10.1016/j.jmr.2005.02.001.

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44

D. Traficante, Daniel. "Elementary trouble-shooting for poor signal-to-noise ratios of NMR spectrometers." Concepts in Magnetic Resonance 2, no. 2 (April 1990): 63–67. http://dx.doi.org/10.1002/cmr.1820020203.

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45

Malmendal, Anders, Claudia Amoresano, Roberta Trotta, Ilaria Lauri, Stefano De Tito, Ettore Novellino, and Antonio Randazzo. "NMR Spectrometers as “Magnetic Tongues”: Prediction of Sensory Descriptors in Canned Tomatoes." Journal of Agricultural and Food Chemistry 59, no. 20 (October 26, 2011): 10831–38. http://dx.doi.org/10.1021/jf203803q.

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46

Zalesskiy, Sergey S., Ernesto Danieli, Bernhard Blümich, and Valentine P. Ananikov. "Miniaturization of NMR Systems: Desktop Spectrometers, Microcoil Spectroscopy, and “NMR on a Chip” for Chemistry, Biochemistry, and Industry." Chemical Reviews 114, no. 11 (April 29, 2014): 5641–94. http://dx.doi.org/10.1021/cr400063g.

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47

Bailey, Nigel J. C., Matjaz Oven, Elaine Holmes, Meinhart H. Zenk, and Jeremy K. Nicholson. "An NMR-based metabolomic approach to the analysis of the effects of xenobiotics on endogenous metabolite levels in plants." Spectroscopy 18, no. 2 (2004): 279–87. http://dx.doi.org/10.1155/2004/862164.

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High field1H NMR spectroscopy has been employed to obtain, in conjunction with chemometric analysis, information regarding fluctuations in endogenous metabolic profiles forCrotalaria cobalticolaplant cells following exposure to cobalt chloride.Such ‘metabolomic’ type data analysis is often confounded by experimental, environmental or genetic factors that are not correlated to the classifications of interest and serve only to complicate the extraction of meaningful answers from a dataset. This work demonstrates the application of data filtering to remove extraneous data that result from spectrometer variation rather than being correlated with the classes of interest. Samples were analysed fromCrotalaria cobalticolasuspension cell culture following exposure to cobalt chloride using 2 spectrometers. Removal of confounding data due to spectrometer variation resulted in clear separation between control and dosed classes. It was then possible to use the model to determine key changes in biochemical status caused as a result of exposure to cobalt. Branched chain amino acids, succinate and secondary metabolite precursors phenylalanine and tyrosine were all higher in the control samples, whilst choline, glutamate, alanine and lactate were higher in the dosed samples.

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48

Gadian, David G. "Sir Rex Edward Richards. 28 October 1922—15 July 2019." Biographical Memoirs of Fellows of the Royal Society 70 (March 10, 2021): 387–407. http://dx.doi.org/10.1098/rsbm.2020.0039.

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Rex Richards was renowned for his research in the field of nuclear magnetic resonance (NMR). Very early on, in the late 1940s, when NMR was in the domain of physicists, he foresaw that the technique might play an important role in chemistry. He embarked on a highly successful research career in which he combined the design and development of new NMR spectrometers with novel applications, initially in chemistry and subsequently in the biological sciences. One major outcome was the establishment of the Oxford Enzyme Group's NMR research programme. Another was the development of 31 P NMR spectroscopy as a non-invasive method of probing the biochemistry of intact biological tissue. Rex was an outstanding teacher and mentor. He also had highly impressive administrative skills, as recognized through successive appointments at the University of Oxford as head of the Physical Chemistry Department, then warden of Merton College and finally vice-chancellor. He was subsequently appointed director of the Leverhulme Trust and became widely respected in the arts world, as reflected by his remarkable array of committee memberships at the National and Tate Galleries.

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Chazov, A. I. "Spinsolve 80 and Spinsolve ULTRA – benchtop NMR spectrometers Magritek Of the research class." Analytics, no. 5 (2017): 70–74. http://dx.doi.org/10.22184/2227-572x.2017.36.5.70.74.

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Morris, Gareth A. "Systematic sources of signal irreproducibility and t1 noise in high-field NMR spectrometers." Journal of Magnetic Resonance (1969) 100, no. 2 (November 1992): 316–28. http://dx.doi.org/10.1016/0022-2364(92)90264-8.

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