Thermal Degradation of Poly(3-hydroxybutyrate) and Poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) in Nitrogen and Oxygen Studied by Thermogravimetric–Fourier Transform Infrared Spectroscopy

2007 ◽  
Vol 61 (7) ◽  
pp. 755-764 ◽  
Author(s):  
Christian Vogel ◽  
Shigeaki Morita ◽  
Harumi Sato ◽  
Isao Noda ◽  
Yukihiro Ozaki ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Fourier Transform ◽  
Thermal Degradation ◽  
Degradation Mechanism ◽  
Fourier Transform Infrared ◽  
Nitrogen Atmosphere ◽  
Correlation Spectroscopy ◽  
Ft Ir ◽  
Higher Temperature ◽  
Ir Spectroscopic

The thermal degradation behavior of poly(3-hydroxybutyrate) (PHB) and poly(3-hydroxybutyrate- co-3-hydroxyhexanoate) (P(HB- co-HHx), HHx = 12 mol%) has been studied under different environmental conditions by thermogravimetric analysis (TGA) Fourier transform infrared (FT-IR) spectroscopy. It is reported that at higher temperature (>400 °C) carbon dioxide and propene are formed from the decomposition product crotonic acid in a nitrogen atmosphere, whereas in an oxygen atmosphere propene oxidizes in a further step to carbon dioxide, carbon monoxide and hydrogen. It was also found that PHB and P(HB- co-HHx) have a similar thermal degradation mechanism. The analysis of the FT-IR-spectroscopic data was performed with 2D and perturbation-correlation moving-window 2D (PCMW2D) correlation spectroscopy.

Identification of Large Isotope Anomalies in Quartz by Infrared Spectroscopy

2019 ◽  
Vol 73 (7) ◽  
pp. 767-773
Author(s):  
Ryan C. Ogliore ◽  
Cosette Dwyer ◽  
Michael J. Krawczynski ◽  
Hélène Couvy ◽  
Max Eisele ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Fourier Transform Infrared Spectroscopy ◽  
Isotope Composition ◽  
Fourier Transform Infrared ◽  
Spectroscopic Technique ◽  
Far Field ◽  
Ft Ir ◽  
Ir Spectroscopic ◽  
Quartz Grains

We report an infrared (IR) spectroscopic technique to detect quartz grains with large isotope anomalies. We synthesized isotopically doped quartz and used Fourier transform infrared spectroscopy (FT-IR) in two different instruments: a traditional far-field instrument and a neaSpec nanoFT-IR, to quantify the shift in the peak of the Si–O stretch near 780 cm−1 as a function of isotope composition, and the uncertainty in this shift. From these measurements, we estimated the minimum detectable isotope anomaly using FT-IR. The described technique can be used to nondestructively detect very small (30 nm) presolar grains. In particular, supernova grains, which can have very large isotope anomalies, are detectable by this method.

Variable-Temperature Fourier Transform Infrared Spectroscopic Investigations of Poly(3-Hydroxyalkanoates) and Perturbation-Correlation Moving-Window Two-Dimensional Correlation Analysis. Part I: Study of Non-Annealed and Annealed Poly(3-Hydroxybutyrate) Homopolymer

2009 ◽  
Vol 63 (9) ◽  
pp. 1027-1033 ◽  
Author(s):  
Miriam Unger ◽  
Shigeaki Morita ◽  
Harumi Sato ◽  
Yukihiro Ozaki ◽  
Heinz W. Siesler
Keyword(s):  
Fourier Transform ◽  
Correlation Analysis ◽  
Crystalline State ◽  
Variable Temperature ◽  
Fourier Transform Infrared ◽  
Melting Behavior ◽  
Correlation Spectroscopy ◽  
Moving Window ◽  
Two Dimensional ◽  
Ft Ir

Generalized two-dimensional correlation spectroscopy (2DCOS) and perturbation-correlation moving-window two-dimensional (PCMW2D) correlation spectroscopy were applied to explore the melting behavior of non-annealed and annealed poly(3-hydroxybutyrate) (PHB) homopolymer as studied by variable-temperature Fourier transform infrared (FT-IR) spectroscopy. The absorption band of the C=O stretching vibration was employed to investigate the structural changes during the heating process (30–200 °C). Non-annealed PHB showed a recrystallization process in the temperature range 30–120 °C. In the asynchronous 2D correlation spectrum we clearly captured the existence of two components in the crystallinity-sensitive wing of the C=O stretching mode: a well-ordered crystalline state at lower wavenumbers (1718 cm−1) and a less ordered crystalline state at higher wavenumbers (1724 cm−1). These crystallinity-sensitive bands at 1718 and 1724 cm−1, which are not readily detectable in the one-dimensional (1D) FT-IR spectra, share asynchronous cross-peaks with bands at around 1737 and 1747 cm−1 assignable to the C=O stretching absorptions due to the amorphous components. In the case of the melting process of non-annealed PHB in the temperature range 120–200 °C, it is helpful to use the PCMW2D correlation analysis, which indicates the recrystallization between 40 and 110 °C by the shift of the C=O stretching band from 1726 cm−1 to 1722 cm−1 and the sharp change to the broad amorphous C=O stretching absorption at 1747 cm−1 at the melting temperature of PHB around 190 °C. For an annealed sample of PHB only the melting behavior was observed in the PCMW2D correlation analysis by the sharp transition from the crystalline to the amorphous C=O stretching band.

scholarly journals Investigation of Differences in the Cultivation of Nannochloropsis and Chlorella species by Fourier-transform Infrared Spectroscopy

2018 ◽  
Vol 62 (4) ◽  
Author(s):  
Bernadett Kiss ◽  
Szilveszter Gergely ◽  
András Salgó ◽  
Áron Németh
Keyword(s):  
Fourier Transform ◽  
Fossil Fuels ◽  
Raw Materials ◽  
Fourier Transform Infrared ◽  
Research Areas ◽  
Ft Ir ◽  
Energy Formation ◽  
Chlorella Species ◽  
Ir Spectroscopic ◽  
Alternative Solutions

The increasing use of energy in the world is leading to the exhaustion of fossil fuels, so novel alternative solutions have to be found to meet our needs. One solution is renewable raw materials extracted from algae. The use of microalgae is widespread, in addition to energy formation, their biomass can also be utilized as food and other valuable components of them, e.g. amino acids, vitamins and minerals can be used in drugs and cosmetics. Due to their boundless diversity and components, they have become the focus of an ever-increasing number of research areas. Different processes can induce changes in their nutritional content, so optimizing the conditions used during their cultivation is important to produce the desired product. In our study different isolates of microalgae, namely Nannochloropsis sp. and Chlorella vulgaris, were studied using Fourier-transform infrared (FT-IR) spectroscopic analysis. Variations in the spectra of a given species were studied under different cultivation conditions.

Protein hydration in living cells probed by Fourier transform infrared (FT-IR) spectroscopic imaging

The Analyst ◽  
2017 ◽  
Vol 142 (13) ◽  
pp. 2475-2483 ◽  
Author(s):  
H. Shinzawa ◽  
B. Turner ◽  
J. Mizukado ◽  
S. G. Kazarian
Keyword(s):  
Fourier Transform ◽  
Ir Spectra ◽  
Spectroscopic Imaging ◽  
Fourier Transform Infrared ◽  
Living Cells ◽  
Protein Hydration ◽  
Ft Ir ◽  
Ir Spectroscopic

FT-IR spectra of a HEK cell were analyzed with 2D disrelation mapping to reveal molecular states of water and protein hydration.

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