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Noël P. G. Roeges

Bio: Noël P. G. Roeges is an academic researcher. The author has contributed to research in topics: Absorption (electromagnetic radiation). The author has an hindex of 1, co-authored 1 publications receiving 1202 citations.

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15 Jan 1994
TL;DR: Normal Vibrations and Absorption Regions of CHX2.0 and CHX3.0 as discussed by the authors Normal Vibration and Absorbance Regions of C( = X)Y.
Abstract: Normal Vibrations and Absorption Regions of CX3. Normal Vibrations and Absorption Regions of CH2X. Normal Vibrations and Absorption Regions of CHX2. Normal Vibrations and Absorption Regions of CHX. Normal Vibrations and Absorption Regions of CX2. Normal Vibrations and Absorption Regions of C(=X)Y. Normal Vibrations and Absorption Regions of Alkenes and Alkynes. Normal Vibrations and Absorption Regions of Nitrogen Compounds. Normal Vibrations and Absorption Regions of Oxy Compounds. Normal Vibrations and Absorption Regions of Sulfur Compounds. Normal Vibrations and Absorption Regions of Ring Structures. Index.

1,244 citations


Cited by
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Journal ArticleDOI
TL;DR: In this paper, the authors used FT-IR attenuated total reflectance (ATR) spectroscopy for the fast characterization of cotton fabric scouring process, and the presence of pectins and/or waxes can also be probed by observation of carbonyl peak induced by the HCl vapor treatment on the fabric.

509 citations

Journal ArticleDOI
TL;DR: In this paper, a review of the most popular IR spectroscopy applications for catalytic applications is presented, starting from the very general basis of the spectroscopic method applied and focusing on the adsorption of chelating compounds on surfaces of mineral oxides.

433 citations

Journal ArticleDOI
TL;DR: The surface of chitosan membranes was modified using a phosphorylation method carried out at room temperature, which pointed out to the presence of phosphates ionically bound to protonated amines, in addition to phosphate esters.
Abstract: In the present work, the surface of chitosan membranes was modified using a phosphorylation method carried out at room temperature. Phosphorylation may be of particular interest in materials for orthopaedic applications, due to the cation-exchange properties of phosphate functionalities. Phosphate groups chelate calcium ions, thus inducing the deposition of an apatite-like layer known to improve the osteoconduction of polymer-based implants. Additionally, the negatively charged phosphate functionalities, together with the positively charged amine groups from chitosan, are expected to provide chitosan with an amphoteric character, which may be useful as a combinatorial therapeutic strategy, by simultaneously allowing the immobilization of signalling molecules like growth factors. Phosphorylation was carried out at room temperature using the H3PO4/Et3PO4/P2O5/butanol method. Surface characterization was performed by XPS, ATR-FT-IR, and SEM. Cross-sections were analyzed by SEM fitted with EDS. The phosphate content increased with the reaction time, as shown by XPS and ATR-FT-IR, a P/N atomic ratio of 0.73 being obtained after 48 h of treatment. High-resolution XPS spectra regarding C1s, O1s, N1s and P2p are discussed. The introduction of a neutralization step led to a reduction of P content, which pointed out to the presence of phosphates ionically bound to protonated amines, in addition to phosphate esters. EDS analysis of cross-sections revealed a gradual P reduction up to 50% towards the inner part of the membrane.

380 citations

Journal ArticleDOI
TL;DR: Fourier transform spectroscopy in the mid-infrared (FT-IR) is being recognized as a powerful tool for analyzing chemical composition of food, with special concern to molecular architecture of food proteins.
Abstract: Fourier transform spectroscopy in the mid-infrared (400–5,000 cm−1) (FT-IR) is being recognized as a powerful tool for analyzing chemical composition of food, with special concern to molecular architecture of food proteins. Unlike other spectroscopic techniques, it provides high-quality spectra with very small amount of protein, in various environments irrespective of the molecular mass. The fraction of peptide bonds in α-helical, β-pleated sheet, turns and aperiodic conformations can be accurately estimated by analysis of the amide I band (1,600–1,700 cm−1) in the mid-IR region. In addition, FT-IR measurement of secondary structure highlights the mechanism of protein aggregation and stability, making this technique of strategic importance in the food proteomic field. Examples of applications of FT-IR spectroscopy in the study of structural features of food proteins critical of nutritional and technological performance are discussed.

334 citations

Journal ArticleDOI
TL;DR: High resolution XPS data support that chlorination increased the number of carboxylic groups on the PA surface, which appear to form by hydrolysis of the amide bonds (C(O)-N).
Abstract: The degradation of polyamide (PA) nanofiltration and reverse osmosis membranes by chlorine needs to be understood in order to develop chlorine-resistant membranes. Coated and uncoated fully aromatic (FA) and piperazine (PIP) semi-aromatic PA membranes were treated with hypochlorite solution and analyzed by X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FTIR). XPS results showed that in chlorine treated FA PA membranes the ratio of bound chlorine to surface nitrogen was 1:1 whereas it was only 1:6 in the case of PIP PA membranes. Surface oxygen of uncoated FA and PIP membranes increased with increasing hypochlorite concentration whereas it decreased for coated FA membranes. High resolution XPS data support that chlorination increased the number of carboxylic groups on the PA surface, which appear to form by hydrolysis of the amide bonds (C(O)–N). FTIR data indicated the disappearance of the amide II band (1541 cm–1) and aromatic amide peak (1609 cm–1) in both coated and uncoated chl...

333 citations