The Determination of Hydroxyl Groups in Coal by Fourier Transform Infrared and 13C NMR Spectroscopy

Fourier transform infrared spectroscopy and solid state 13C NMR spectroscopy have been used to measure the hydroxyl groups in coal. The methodology depends upon measuring the intensities of bands and resonances assigned to the products of acetylation reactions. In the infrared three separate bands, assigned to acetylated phenolic OH, alkyl OH, and NH groups, can be identified. In NMR, we used the methoxy carbon to determine the total OH. Spectroscopic measurements demonstrate that not only does the total OH content of coals but also the individual types of OH groups vary systematically as a function of rank. The proportion of phenolic to alkyl OH is approximately constant for the coals used in this study.

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Fourier transform infrared analysis of hydroxyl content of hydrothermally processed heteroepitaxial barium titanate films

Journal of Materials Research ◽

10.1557/jmr.2005.0406 ◽

2005 ◽

Vol 20 (12) ◽

pp. 3312-3319 ◽

Cited By ~ 8

Author(s):

Sandeep K. Patil ◽

Nipun Shah ◽

Frank D. Blum ◽

Mohamed N. Rahaman

Keyword(s):

Fourier Transform ◽

Barium Titanate ◽

Exchange Reaction ◽

Photoelectron Spectroscopy ◽

Fourier Transform Infrared ◽

Infrared Analysis ◽

Hydroxyl Groups ◽

Oh Groups ◽

Kinetics Of ◽

Total Reaction Time

The concentration of hydroxyl (–OH) groups in epitaxial barium titanate (BaTiO3) films (thickness ∼ 200 nm), deposited on single-crystal strontium titanate (SrTiO3) at 150 °C by a hydrothermal technique, was investigated using x-ray photoelectron spectroscopy and Fourier transform infrared (FTIR) spectroscopy. After hydrothermal treatment, a broad FTIR resonance for the hydroxyl groups indicated a significant concentration of surface –OH groups in the films. The as-deposited films were subsequently treated hydrothermally with D2O, and the kinetics of the exchange reaction between –OH incorporated into the film and –OD from the D2O were studied using FTIR. For reactions carried out intermittently, the kinetics of the exchange reaction between –OH by –OD depended not only on the total reaction time, but also on the duration of each treatment. The broad FTIR hydroxyl resonance in the as-deposited hydrothermal film was significantly reduced only after heating for 1 h at 600–800 °C.

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Identification and quantitative determination of carbohydrate molecules in Greek honey by employing 13C NMR spectroscopy

Analytical Methods ◽

10.1039/c5ay01243k ◽

2015 ◽

Vol 7 (14) ◽

pp. 5962-5972 ◽

Cited By ~ 15

Author(s):

Aristea Kazalaki ◽

Maria Misiak ◽

Apostolos Spyros ◽

Photis Dais

Keyword(s):

Nmr Spectroscopy ◽

Quantitative Determination ◽

13C Nmr ◽

13C Nmr Spectroscopy ◽

C Nmr

A methodology based on 13C NMR spectroscopy was employed to detect and quantify fourteen mono-, di- and trisaccharide molecules in authentic Greek honey samples with no prior separation.

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Chemistry of chromotropic acid. 1H and 13C NMR spectroscopy of chromotropic acid and its derivatives

Canadian Journal of Chemistry ◽

10.1139/v91-180 ◽

1991 ◽

Vol 69 (8) ◽

pp. 1207-1211 ◽

Cited By ~ 3

Author(s):

Paris E. Georghiou ◽

Chi Keung (Jimmy) Ho ◽

Chester R. Jablonski

Keyword(s):

Nmr Spectroscopy ◽

13C Nmr ◽

Nmr Spectra ◽

Deuterium Oxide ◽

13C Nmr Spectroscopy ◽

Chromotropic Acid ◽

Hydroxyl Groups ◽

Two Dimensional ◽

1H And 13C Nmr ◽

C Nmr

The 1H and 13C NMR spectra of chromotropic acid (CTA) (4,5-dihydroxy-2,7-naphthalenedisulphonic acid) have been unambiguously assigned. Proton NOED spectra were used to show the proximity of both H-3 and H-6 and the hydroxyl groups. Two-dimensional 1H–13C NMR correlation spectra of CTA, of its corresponding diacetoxy derivative, and of 3-bromo- and 3,6-dibromo-CTA support the assignments. A regioselective deuterium exchange reaction of the C-3 and C-6 protons of CTA with deuterium oxide was observed during the NMR experiments. This latter finding is strongly indicative of the mode of formation, and of the nature of the chromogen formed in the reaction of CTA with formaldehyde in the well-known CTA-formaldehyde analytical reaction. Key words: chromotropic acid, 3-bromochromotropic acid, 3,6-dibromochromotropic acid.

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Determination of C-23 Configuration in (20R)-23-Hydroxycholestane Side Chain of Steroid Compounds by 1H and 13C NMR Spectroscopy

Natural Product Communications ◽

10.1177/1934578x1300800908 ◽

2013 ◽

Vol 8 (9) ◽

pp. 1934578X1300800 ◽

Cited By ~ 2

Author(s):

Alla A. Kicha ◽

Anatoly I. Kalinovsky ◽

Alexander S. Antonov ◽

Oleg S. Radchenko ◽

Natalia V. Ivanchina ◽

...

Keyword(s):

Nmr Spectroscopy ◽

13C Nmr ◽

13C Nmr Spectroscopy ◽

Side Chain ◽

Side Chains ◽

Model Compounds ◽

1H And 13C Nmr ◽

C 23 ◽

C Nmr

Epimeric (20 R,23 R)- and (20 R,23 S)-23-hydroxycholestane steroids were synthesized. Their structures were elucidated by extensive 1H and 13C NMR spectroscopy and application of the Mosher's method. All proton and carbon signals of the side chains were assigned. Based on these assignments spectral data allow the determination of the C-23 stereochemistry of (20 R)-23-hydroxycholestane side chains of the new natural steroids by comparison with spectra of the obtained model compounds. As a result, the C-23 configuration of two steroid compounds from the starfishes Lethasterias nanimensis chelifera and Lethasterias fusca was established.

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