scholarly journals Determination of Polymerization Degree of Maltooligosaccharides by FT-IR/ATR Spectroscopy.

2001 ◽  
Vol 48 (6) ◽  
pp. 401-408 ◽  
Author(s):  
Mikihito KANOU ◽  
Atsushi HASHIMOTO ◽  
Yasuhiko SHIINOKI ◽  
Kensuke ITO ◽  
Yoshitaka MOTONAGA ◽  
...  
1992 ◽  
Vol 46 (3) ◽  
pp. 529-532 ◽  
Author(s):  
Masaaki Harada ◽  
Takehiko Kitamori ◽  
Norio Teramae ◽  
Kiyokazu Hashimoto ◽  
Shohei Oda ◽  
...  

Concentration depth profiling of functional groups using FT-IR/ATR spectroscopy has been applied to the nondestructive determination of the degree of saponification. A two-layered film, which had acetyl groups in its surface layer distributed inhomogeneously in the depth direction, was prepared. The dependence of its FT-IR/ATR spectra on incident angles was measured. The degree of saponification was determined on the basis of the concentration depth profile of the acetyl groups obtained from the angular dependency. The results obtained showed good agreement with micro FT-IR and neutralization titration results. This method is judged able to determine functional groups within the range of a few micrometers from the sample surface.


2008 ◽  
Vol 59 (4) ◽  
Author(s):  
Irina Crina Anca Sandu ◽  
Constantin Luca ◽  
Ion Sandu ◽  
Viorica Vasilache ◽  
Mikiko Hayashi

This is the second paper belonging to a study concerning the authentication of ancient easel-paintings, on canvas and wood support, from private and public collections, by using the FT-IR spectrophotometry technique for the analysis of the painting materials. Different pigments, egg binders, caseins and animal glue, often found in ancient easel-paintings on wood or canvas, have been used as standards for establishing the ageing rate of the paintings by correlation with the dates presented in the first note. The determination of the degradation rate of the painting materials is an important archaeometric characteristic used in authentication.


2021 ◽  
Vol 22 (8) ◽  
pp. 4018
Author(s):  
Anna Masek ◽  
Angelika Plota

In the field of polymer technology, a variety of mainly synthetic additives are used to stabilize the materials during processing. However, natural compounds of plant origin can be a green alternative to chemicals such as synthetic polyphenols. An analysis of the effect of hesperidin on the aging behavior of ethylene-norbornene copolymer was performed. The evaluation of changes in the tested samples was possible by applying the following tests: determination of the surface energy and OIT values, mechanical properties analysis, colour change measurements, FT-IR and TGA analyses. The obtained results proved that hesperidin can be effectively used as natural stabilizer for polymers. Furthermore, as a result of this compound addition to Topas-silica composites, their surface and physico-mechanical properties have been improved and the resistance to aging significantly increased. Additionally, hesperidin can act as a dye or colour indicator and only few scientific reports describe a possibility of using flavonoids to detect changes in products during their service life, e.g., in food packaging. In the available literature, there is no information about the potential use of hesperidin as a stabilizer for cycloolefin copolymers. Therefore, this approach may contribute not only to the current state of knowledge, but also presents an eco-friendly solution that can be a good alternative to synthetic stabilizers.


2002 ◽  
Vol 56 (4) ◽  
pp. 509-514 ◽  
Author(s):  
Xiaohua Yi ◽  
Karen Nerbonne ◽  
John Pellegrino

We present an experimental method for measuring diffusion of lubricants (or any highly viscous fluid) in polymers using Fourier transform infrared (FT-IR) attenuated total reflection (ATR) spectroscopy. Unlike the conventional FT-IR ATR diffusion measurement, in which a polymer sample is sandwiched between the penetrant and an internal reflection element (IRE), in this method, a thin layer of penetrant (for example, a lubricant) is sandwiched between the IRE and the polymer sample. This allows accurate control and measurement of the thickness of the lubricant layer, which, in turn, facilitates subsequent data analysis. The diffusion is studied by monitoring the time-resolved change in absorbance of either a unique polymer or penetrant band. A feature of this new method is that it can provide an estimate of solubility, as well as an estimate of the diffusivity of the penetrant in the polymer. Using this method, we studied the diffusion of mineral oil and a commercial fluorocarbon ether lubricant (Krytox® 143AC‡) in poly(propylene) (PP) film at room temperature. The experimental data was modeled using a Fickian model with impermeable and saturated boundary conditions applied at the IRE/lubricant and lubricant/polymer interfaces, respectively. The diffusivity and solubility of mineral oil in PP were found to be 1.34 ± 0.35 (×10−10) cm2/s and 0.77 ± 0.13 (×10−2) g/g of PP, respectively. The current model was unable to quantitatively describe the diffusion of the Krytox® 143AC in the PP, possibly due to excessive swelling.


1994 ◽  
Vol 66 (23) ◽  
pp. 4354-4358 ◽  
Author(s):  
Yoshimasa. Ogawara ◽  
Albert. Bruneau ◽  
Takako. Kimura

2020 ◽  
Vol 42 (6) ◽  
pp. 856-856
Author(s):  
Sehrish Qazi Sehrish Qazi ◽  
Huma Shaikh Huma Shaikh ◽  
Ayaz Ali Memon Ayaz Ali Memon ◽  
and Shahabuddin Memon and Shahabuddin Memon

Among all psychotropic alkaloids, nicotine is more addictive, carcinogenic and capable of causing many health problems. This work is based on the development of highly robust, cheap, reliable, selective and sensitive nicotine imprinted graphene oxide nanocomposite (ImpGO nanocomposite) based optical sensor for determination of nicotine in human plasma. The ImpGO nanocomposite has been thoroughly characterized using different techniques i.e. FT-IR, SEM, TEM, Raman, etc. These characterizations revealed that ImpGO nanocomposite is comprised of single layer of graphene oxide successfully modified with imprinted polymer. The synthesized material was utilized to selectively determine nicotine using UV-vis spectrophotometer in BR buffer of 0.1 M at pH 3 and diluted human plasma. The effect of parameters such as buffer concentration, pH, amount of nanocomposite, etc on determination of nicotine using ImpGO nanocomposite were studied thoroughly. Thus, a sensitive optical method was developed for determination of nicotine in human plasma with linear range of 22-370 pM along with LOD and LOQ of 7 pM and 22 pM, respectively. The selectivity of sensor was evaluated using homologues of nicotine such as nicotine amide, caffeine and cotinine. The results obtained from biological samples showed that developed optical sensor is efficient in complex matrices of real sample.


2014 ◽  
Vol 62 ◽  
pp. 22-33 ◽  
Author(s):  
Raquel Rodríguez-Solana ◽  
Dimitra J. Daferera ◽  
Christina Mitsi ◽  
Panayiotis Trigas ◽  
Moschos Polissiou ◽  
...  

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