A Role of Infrared and Raman Spectroscopy in Evaluating the Structure and Properties of Fibers

1990 ◽  
Vol 46 (9) ◽  
pp. P401-P407 ◽  
Author(s):  
KOHJI TASHIRO
Keyword(s):  
Raman Spectroscopy ◽  
Structure And Properties ◽  
Infrared And Raman Spectroscopy

Formation, Structure, and Properties of Nitrosonium and Nitronium Fluorosulfate

1971 ◽  
Vol 49 (1) ◽  
pp. 35-44 ◽  
Author(s):  
A. M. Qureshi ◽  
H. A. Carter ◽  
F. Aubke
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Raman Spectroscopy ◽  
Structure And Properties ◽  
Unit Cell Parameters ◽  
Monoclinic System ◽  
X Ray ◽  
Cell Parameters ◽  
Infrared And Raman Spectroscopy ◽  
Ionic Compounds ◽  
Intermediate Oxidation

The reactions of the nitrogen oxides, N2O, NO, N2O3, NO2 (N2O4), and N2O5, the oxychlorides ClNO and ClNO2, and the oxyanions NO2− and NO3− with the fluorosulfonating agents S2O6F2 and BrOSO2F are studied systematically in regard to the formation of nitrosonium and nitronium fluorosulfate. Complex reactions are found when N2O3 and N2O4 are used as substrates, resulting in mixed or impure products. An explanation involving the intermediate oxidation into N2O5 is put forward to explain the results.The solid products NOSO3F and NO2SO3F are characterized by powder X-ray analysis, infrared and Raman spectroscopy, and their solution behavior in HSO3F. Whereas NOSO3F has been found to have an orthorhombic lattice, NO2SO3F crystallizes in the monoclinic system. Unit cell parameters are reported. The vibrational spectra are interpreted in terms of ionic compounds NO+SO3F− and NO2+ − SO3F−. The SO3F− anion, however, appears to be perturbed and all the E modes are slightly split. No unambiguous evidence for a previously reported non-linear NO2+ cation is found. Force constants for this species are calculated assuming D∞h symmetry.Both compounds are found to be completely dissociated in HSO3F as evidenced by conductometry and 1H and 19F nuclear magnetic resonance (n.m.r.) spectroscopy.

Identification of filler substances in emeralds by infrared and Raman spectroscopy

2000 ◽  
Vol 26 (1) ◽  
pp. 501-520 ◽  
Author(s):  
L. Kiefert ◽  
H.A. Hänni ◽  
J-P. Chalain ◽  
W. Weber
Keyword(s):  
Raman Spectroscopy ◽  
Infrared And Raman Spectroscopy

Exploring the Biological Protective Role of Carotenoids by Raman Spectroscopy: Mechanical Stress of Cells

2019 ◽  
Vol 64 (1-2) ◽  
pp. 75-82
Author(s):  
F. Nekvapil ◽  
◽  
Cs. Müller Molnár ◽  
S. Tomšić ◽  
S. Cintă Pinzaru ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Mechanical Stress ◽  
Protective Role

scholarly journals Multivariate approach for the authentication of vanilla using infrared and Raman spectroscopy

2021 ◽  
Vol 141 ◽  
pp. 110196
Author(s):  
Ana M. Jiménez-Carvelo ◽  
Margherita Tonolini ◽  
Orla McAleer ◽  
Luis Cuadros-Rodríguez ◽  
Daniel Granato ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Multivariate Approach ◽  
Infrared And Raman Spectroscopy

scholarly journals Authentication of the Botanical and Geographical Origin and Detection of Adulteration of Olive Oil Using Gas Chromatography, Infrared and Raman Spectroscopy Techniques: A Review

Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1565
Author(s):  
Eleni Kakouri ◽  
Panagiota-Kyriaki Revelou ◽  
Charalabos Kanakis ◽  
Dimitra Daferera ◽  
Christos S. Pappas ◽  
...  
Keyword(s):  
Gas Chromatography ◽  
Raman Spectroscopy ◽  
Olive Oil ◽  
Nutritional Value ◽  
Review Paper ◽  
Geographical Origin ◽  
Analytical Techniques ◽  
Volatile Fraction ◽  
Olive Oils ◽  
Infrared And Raman Spectroscopy

Olive oil is among the most popular supplements of the Mediterranean diet due to its high nutritional value. However, at the same time, because of economical purposes, it is also one of the products most subjected to adulteration. As a result, authenticity is an important issue of concern among authorities. Many analytical techniques, able to detect adulteration of olive oil, to identify its geographical and botanical origin and consequently guarantee its quality and authenticity, have been developed. This review paper discusses the use of infrared and Raman spectroscopy as candidate tools to examine the authenticity of olive oils. It also considers the volatile fraction as a marker to distinguish between different varieties and adulterated olive oils, using SPME combined with gas chromatography technique.

scholarly journals Structural and Technological Approach to Reveal the Role of the Lipid Phase in the Formation of Soy Emulsion Gels with Chia Oil

Gels ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 48
Author(s):  
Ana M. Herrero ◽  
Claudia Ruiz-Capillas
Keyword(s):  
Raman Spectroscopy ◽  
Structural Properties ◽  
Structural Changes ◽  
Protein Secondary Structure ◽  
Lipid Phase ◽  
Α Helix ◽  
Β Sheet ◽  
Shed Light ◽  
Chia Oil

Considerable attention has been paid to emulsion gels (EGs) in recent years due to their interesting applications in food. The aim of this work is to shed light on the role played by chia oil in the technological and structural properties of EGs made from soy protein isolates (SPI) and alginate. Two systems were studied: oil-free SPI gels (SPI/G) and the corresponding SPI EGs (SPI/EG) that contain chia oil. The proximate composition, technological properties (syneresis, pH, color and texture) and structural properties using Raman spectroscopy were determined for SPI/G and SPI/EG. No noticeable (p > 0.05) syneresis was observed in either sample. The pH values were similar (p > 0.05) for SPI/G and SPI/EG, but their texture and color differed significantly depending on the presence of chia oil. SPI/EG featured significantly lower redness and more lightness and yellowness and exhibited greater puncture and gel strengths than SPI/G. Raman spectroscopy revealed significant changes in the protein secondary structure, i.e., higher (p < 0.05) α-helix and lower (p < 0.05) β-sheet, turn and unordered structures, after the incorporation of chia oil to form the corresponding SPI/EG. Apparently, there is a correlation between these structural changes and the textural modifications observed.

scholarly journals A Unified Mathematical Formalism for First to Third Order Dielectric Response of Matter: Application to Surface-Specific Two-Colour Vibrational Optical Spectroscopy

Symmetry ◽  
2021 ◽  
Vol 13 (1) ◽  
pp. 153 ◽  
Author(s):  
Christophe Humbert ◽  
Thomas Noblet
Keyword(s):  
Dielectric Response ◽  
Structure And Properties ◽  
Linear Optics ◽  
Third Order ◽  
Mathematical Functions ◽  
Sum Frequency ◽  
Non Linear Optics ◽  
Non Linear ◽  
Light Excitation

To take advantage of the singular properties of matter, as well as to characterize it, we need to interact with it. The role of optical spectroscopies is to enable us to demonstrate the existence of physical objects by observing their response to light excitation. The ability of spectroscopy to reveal the structure and properties of matter then relies on mathematical functions called optical (or dielectric) response functions. Technically, these are tensor Green’s functions, and not scalar functions. The complexity of this tensor formalism sometimes leads to confusion within some articles and books. Here, we do clarify this formalism by introducing the physical foundations of linear and non-linear spectroscopies as simple and rigorous as possible. We dwell on both the mathematical and experimental aspects, examining extinction, infrared, Raman and sum-frequency generation spectroscopies. In this review, we thus give a personal presentation with the aim of offering the reader a coherent vision of linear and non-linear optics, and to remove the ambiguities that we have encountered in reference books and articles.

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