Characterizing the Three-Dimensional Orientation in Polymers using FT-IR Spectroscopy with Linear Polarized Light

2010 ◽  
Vol 211 (20) ◽  
pp. 2233-2239 ◽  
Author(s):  
Robert Brüll ◽  
Raquel Maria ◽  
Karsten Rode
Keyword(s):  
Ir Spectroscopy ◽  
Three Dimensional ◽  
Polarized Light ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

Protein secondary structure from FT-IR spectroscopy: correlation with dihedral angles from three-dimensional Ramachandran plots

1991 ◽  
Vol 69 (11) ◽  
pp. 1639-1642 ◽  
Author(s):  
Michael Jackson ◽  
Henry H. Mantsch
Keyword(s):  
Ir Spectroscopy ◽  
Three Dimensional ◽  
Protein Secondary Structure ◽  
Secondary Structures ◽  
Dihedral Angles ◽  
Carbonyl Groups ◽  
Amide Carbonyl ◽  
Ft Ir ◽  
Ft Ir Spectroscopy ◽  
Hydrogen Bonded

The frequency of the so-called "amide I" band (amide C=O stretching vibration, vC=O) of proteins is discussed in terms of the dihedral angles of the various secondary structures present within proteins. We propose that in the case of intra- or intermolecular hydrogen-bonded amide carbonyl groups the frequency of this absorption can be directly related to the [Formula: see text], ψ angles of the amide moieties for the major secondary structures. Amide I bands at frequencies above those found for non-hydrogen bonded amide carbonyl groups are rationalized in terms of a change in the third dihedral angle, ω. Rotation around the amide C—N bond in sterically demanding structures, such as turns where ω deviates from 180°, is expected to cause an increase in the electron density of the amide carbonyl groups and so increase vC=O to frequencies greater than that seen for unperturbed carbonyl groups. Key words: FT-IR spectroscopy, proteins, structure, dihedral angles.

Thermal Cure Study of a Low-k Methyl Silsesquioxane for Intermetal Dielectric Application by FT-IR Spectroscopy

2000 ◽  
Vol 54 (2) ◽  
pp. 209-213 ◽  
Author(s):  
C. Y. Wang ◽  
Z. X. Shen ◽  
J. Z. Zheng
Keyword(s):  
Ir Spectroscopy ◽  
Structural Changes ◽  
Semiconductor Device ◽  
Three Dimensional ◽  
Device Fabrication ◽  
Cross Linking ◽  
Low Dielectric ◽  
Ft Ir ◽  
Methyl Silsesquioxane ◽  
Ft Ir Spectroscopy

In this paper, Fourier transform infrared (FT-IR) spectroscopy is used to study the thermal properties of methyl silsesquioxane (MSQ), an important low-dielectric-constant organic spin-on glass for semiconductor device fabrication. The compositional and structural changes of MSQ with temperature are investigated in detail. The cross-linking process, where the three-dimensional networked structure is formed, is found to start at room temperature, and is almost complete at the typical baking temperature of 250 °C. Further cross-linking occurs during the curing process at 425 °C, and small short-chain clusters can also be driven away at this temperature by sublimation. In this study, we have assigned all the MSQ IR peaks and we have used the long-chain O–Si–O IR peak to calculate the “degree of cross-linking” quantitatively.

Multiscale exploration of hydrocarbons adsorption and hopping through the ZSM-5 channels - from Monte Carlo modelling to experiment

2021 ◽  
Author(s):  
Maciej Strzempek ◽  
Karolina A. Tarach ◽  
Kinga Góra-Marek ◽  
Fernando Rey ◽  
Miguel Palomino ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Ir Spectroscopy ◽  
Aliphatic Hydrocarbons ◽  
Adsorption Studies ◽  
Ft Ir ◽  
Gravimetric Adsorption ◽  
Hydrocarbons Adsorption ◽  
Ft Ir Spectroscopy

Abstract In this article the results of the statistical MC modelling corroborated by the FT-IR spectroscopy and gravimetric adsorption studies of the low aliphatic hydrocarbons in ZSM-5 (Si/Al =28 or...

scholarly journals Vibrational Spectroscopic Investigation of Blood Plasma and Serum by Drop Coating Deposition for Clinical Application

2021 ◽  
Vol 22 (4) ◽  
pp. 2191
Author(s):  
Jing Huang ◽  
Nairveen Ali ◽  
Elsie Quansah ◽  
Shuxia Guo ◽  
Michel Noutsias ◽  
...  
Keyword(s):  
Ir Spectroscopy ◽  
Outer Ring ◽  
Imaging Method ◽  
Fluorescence Lifetime Imaging ◽  
Drying Process ◽  
Vibrational Signal ◽  
Coating Deposition ◽  
Ft Ir ◽  
Sample Droplet ◽  
Ft Ir Spectroscopy

In recent decades, vibrational spectroscopic methods such as Raman and FT-IR spectroscopy are widely applied to investigate plasma and serum samples. These methods are combined with drop coating deposition techniques to pre-concentrate the biomolecules in the dried droplet to improve the detected vibrational signal. However, most often encountered challenge is the inhomogeneous redistribution of biomolecules due to the coffee-ring effect. In this study, the variation in biomolecule distribution within the dried-sample droplet has been investigated using Raman and FT-IR spectroscopy and fluorescence lifetime imaging method. The plasma-sample from healthy donors were investigated to show the spectral differences between the inner and outer-ring region of the dried-sample droplet. Further, the preferred location of deposition of the most abundant protein albumin in the blood during the drying process of the plasma has been illustrated by using deuterated albumin. Subsequently, two patients with different cardiac-related diseases were investigated exemplarily to illustrate the variation in the pattern of plasma and serum biomolecule distribution during the drying process and its impact on patient-stratification. The study shows that a uniform sampling position of the droplet, both at the inner and the outer ring, is necessary for thorough clinical characterization of the patient’s plasma and serum sample using vibrational spectroscopy.

FT-IR Spectroscopy As A Tool For The Study Of Metal Ions/D- Galactose Complexes

1989 ◽  
Author(s):  
Ning Xi ◽  
Shifu Weng ◽  
Jinguang Wu ◽  
Guangxian Xu
Keyword(s):  
Ir Spectroscopy ◽  
Metal Ions ◽  
Ft Ir ◽  
Ft Ir Spectroscopy
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