scholarly journals Infrared Spectra: Useful Technique to Identify the Conductivity Level of Emeraldine form of Polyaniline and Indication of Conductivity Measurement either Two or Four Probe Technique

2018 ◽  
Vol 15 (3) ◽  
pp. 209-217 ◽  
Author(s):  
Palaniappan Srinivasan ◽  
Ramesh Gottam

A new insight was watched the connection between’s the conductivity and Fourier Transform Infrared (FT-IR) spectra of the emeraldine type of polyaniline (PANI) structures. The conductivity of polyaniline emeraldine salt (PANI-ES) can be varied from 101 to 10-12 S cm-1. FT-IR spectrum is a tool to determine the conductivity level and also conductivity measuring methods of PANI system, i.e., either two probe or four probe techniques. This information is very useful for the researcher and industrialists working on emeraldine form of PANI systems to identify the conductivity level and method of measurements from FT-IR spectra. This data was seen from the infrared spectra of different PANI salts obtained by the oxidation of aniline in water/solvent medium by ammonium persulfate (APS) without utilizing any acids. PANI-ES samples having reasonably good conductivity (> 0.3 S cm-1) showed mostly nanowires or nanorods morphology, whereas, lower conductivity (< 0.3 S cm-1) samples showed mostlyagglomerated spheres or particles morphology. In these investigations, however, no report was made of the use of infrared technic to determine the conductivity of PANI system.

1998 ◽  
Vol 52 (7) ◽  
pp. 990-993 ◽  
Author(s):  
M. Khalique Ahmed ◽  
Jim Daun ◽  
Doug Declercq

Development of varieties of high-erucic-acid (HEAR) rapeseed with high levels of erucic acid (C22:1) would be valuable for use in oleochemical feedstocks. As an aid to this breeding effort, a rapid method to detect trierucin (C22:1 triacylglycerol), an indicator that erucic acid is being incorporated in all three positions of the triacylglycerol, would be useful. Fingerprint (1850–600 cm−1) Fourier transform infrared (FT-IR) spectra of HEAR oil extracted from Brassica napus L. cv. Mercury, trierucin, and varying amounts of trierucin spiked in this oil were recorded. The regions of 1790–1690 cm−1 and 1485–990 cm−1 were subjected to a partial least-squares (PLS) procedure to obtain a calibration equation [ R2 = 0.992 and root-mean-squared deviation (RMSD) = 2.78]. The established calibration was then tested on the spectra of mixtures of another HEAR oil from B. napus cv. Turret and trierucin. The predicted values differ from the actual values with an RMSD of 1.6%. The calibration was also tested on high-erucic-acid oils from crambe ( Crambe abyssinica) and nasturtium ( Tropaeolum majus L.) seeds. For crambe, the value found (0.4%) was close to that reported in the literature, while the value of 75% for nasturtium oil was close to the value for total triacylglycerols with erucic acid in the 2-position as reported in the literature. FT-IR spectra of triolein (C18: 1 triacylglycerol), trieicosenoin (C20:1 triacylglycerol), and trinervonin (C24:1 triacylglycerol) compared with the FT-IR spectrum of trierucin revealed the uniqueness of IR spectrum of trierucin that forms the basis of PLS analysis of trierucin in HEAR oils.


2019 ◽  
Vol 74 (1) ◽  
pp. 119-124
Author(s):  
Sebastian Fäth ◽  
Max Vilsmeier ◽  
Arno Pfitzner

AbstractThe title compounds C13H26N+Cl− (N,N-dicyclohexylmethylammonium chloride), C13H26N+Br− (N,N- dicyclohexylmethylammonium bromide) and C13H26N+I− (N,N-dicyclohexylmethylammonium iodide) are isostructural and crystallize in the orthorhombic space group Pna21 with the lattice parameters a=7.580(1), b=19.072(1), c=9.165(1) Å, V=1324.9(1) Å3 for X=Cl, a=7.765(1), b=19.054(1), c=9.270(1) Å, V=1371.5(1) Å3 for X=Br, and a=8.102(1), b=19.084(1), c=9.535(1) Å, V=1474.2(1) Å3 for X=I with Z=4 for each compound. Their cyclohexyl groups are aligned along [010] while their halide ions are coordinated along [100] by a strong linear N–H···X (X=Cl, Br, I) hydrogen bond. Fourier-transform infrared spectra show a decreasing hydrogen bond acceptor strength from the chloride to the iodide.


1989 ◽  
Vol 43 (2) ◽  
pp. 298-304 ◽  
Author(s):  
W. M. Coleman ◽  
Bert M. Gordon ◽  
Brian M. Lawrence

Matrix isolation Fourier transform infrared spectra (MI/FT-IR), mass spectra (MS), carbon-13 Nuclear Magnetic Resonance (13C-NMR) spectra, condensed-phase infrared spectra, and vapor-phase infrared (IR) spectra are presented for a series of terpene compounds. Subtle differences in positional and configurational isomers commonly found with terpenes could be easily detected by the MI/FT-IR spectra. The results are comparable in some aspects to those obtainable from 13C-NMR and thin-film IR; however, most importantly, they are acquired at the low nanogram level for MI/FT-IR, as compared to the milligram level for the other techniques. These results represent an advance in the technology available for the analysis of complex mixtures such as essential oils containing terpene-like molecules.


1989 ◽  
Vol 43 (8) ◽  
pp. 1317-1324 ◽  
Author(s):  
Charles J. Wurrey ◽  
Billy J. Fairless ◽  
Harry E. Kimball

Reference-quality gas chromatographic/matrix isolation/Fourier transform infrared spectra have been recorded for the following fifteen compounds, which collectively are referred to as the “laterally” chlorinated dibenzo- p-dioxins and dibenzofurans: 2,3,7,8-tetrachlorodibenzo- p-dioxin (2,3,7,8-TCDD); 1,2,3,7,8-pentachlorodibenzo- p-dioxin (1,2,3,7,8-PeCDD);l,2,3,4,7,8-hexachlorodibenzo- p-dioxin(1,2,3,4,7,8-HxCDD)>; 1,2,3,6,7,8,-hexachlorodibenzo- p-dioxin(1,2,3,6,7,8-HxCDD); 1,2,3,7,8,9-hexachlorodibenzo- p-dioxin (1,2,3,7,8,9-HxCDD); 1,2,3,4,6,7,8-heptachlorodibenzo- p-dioxin (1,2,3,4,6,7,8-HpCDD); 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF); 1,2,3,7,8-pentachlorodibenzofuran (1,2,3,7,8-PeCDF); 2,3,4,7,8-pentachlorodibenzofuran (2,3,4,7,8-PeCDF); 1,2,3,4,7,8-hexachlorodibenzofuran(1,2,3,4,7,8-HxCDF); 1,2,3,6,7,8-hexachlorodibenzofuran (1,2,3,6,7,8-HxCDF); 1,2,3,7,8,9-hexachlorodibenzofuran (1,2,3,7,8,9-HxCDF); 2,3,4,6,7,8-hexachlorodibenzofuran (2,3,4,6,7,8-HxCDF); 1,2,3,4,6,7,8-heptachlorodibenzofnran (1,2,3,4,6,7,8-HpCDF); and 1,2,3,4,7,8,9-heptachlorodibenzofuran (1,2,3,4,7,8,9-HpCDF). These spectra are discussed qualitatively and, for the laterally chlorinated dioxins, are compared to previously recorded gas-phase GC/FT-IR spectra. Estimates of the instrumental detection limits for these compounds, using matrix isolation GC/FT-IR spectroscopy, were found to fall in the mid-to-high picogram and low nanogram ranges.


2010 ◽  
Vol 76 (11) ◽  
pp. 3538-3544 ◽  
Author(s):  
Ornella Preisner ◽  
Raquel Guiomar ◽  
Jorge Machado ◽  
Jos� Cardoso Menezes ◽  
Jo�o Almeida Lopes

ABSTRACT Fourier transform infrared (FT-IR) spectroscopy and chemometric techniques were used to discriminate five closely related Salmonella enterica serotype Enteritidis phage types, phage type 1 (PT1), PT1b, PT4b, PT6, and PT6a. Intact cells and outer membrane protein (OMP) extracts from bacterial cell membranes were subjected to FT-IR analysis in transmittance mode. Spectra were collected over a wavenumber range from 4,000 to 600 cm−1. Partial least-squares discriminant analysis (PLS-DA) was used to develop calibration models based on preprocessed FT-IR spectra. The analysis based on OMP extracts provided greater separation between the Salmonella Enteritidis PT1-PT1b, PT4b, and PT6-PT6a groups than the intact cell analysis. When these three phage type groups were considered, the method based on OMP extract FT-IR spectra was 100% accurate. Moreover, complementary local models that considered only the PT1-PT1b and PT6-PT6a groups were developed, and the level of discrimination increased. PT1 and PT1b isolates were differentiated successfully with the local model using the entire OMP extract spectrum (98.3% correct predictions), whereas the accuracy of discrimination between PT6 and PT6a isolates was 86.0%. Isolates belonging to different phage types (PT19, PT20, and PT21) were used with the model to test its robustness. For the first time it was demonstrated that FT-IR analysis of OMP extracts can be used for construction of robust models that allow fast and accurate discrimination of different Salmonella Enteritidis phage types.


2015 ◽  
Vol 642 ◽  
pp. 259-263
Author(s):  
Hirotomo Watanabe ◽  
Chiharu Tadokoro ◽  
Shinya Sasaki

To understand the effects of tribo-film formation derived from ZnDTP (zinc dialkyl ditio phosphate) on friction behavior, friction tests were carried out with varying sliding time. The sliding surfaces were analyzed using Fourier transform infrared spectroscopy (FT-IR) and X-ray Photoelectron Spectroscopy (XPS). On the basis of the surface analytical results of the tribo-film, the absorption bands in the region of 1300-1000 cm-1 assigned as polyphosphate appeared in all IR spectra after the sliding. The friction behavior of ZnDTP was related to the intensity change of the IR spectra peak at 1200 cm-1.


1989 ◽  
Vol 43 (6) ◽  
pp. 998-1003 ◽  
Author(s):  
W. M. Coleman ◽  
Bert M. Gordon

A set of five search routines—absolute difference, absolute derivative, square difference, square derivative, and Euclidean difference—have been applied to the analysis of the matrix isolation/Fourier transform-infrared spectra (MI/FT-IR) of the components of four essential oils: coriander oil, lemon oil, geranium oil, and citronella oil. The routines were tested under a variety of parameters on a diverse set of compounds and IR spectra. Areas of acceptable performance by the routines as well as areas of marginal performance are discussed. Under the conditions of this study, the absolute derivative routine is judged to be the most acceptable of the five.


2012 ◽  
Vol 554-556 ◽  
pp. 2049-2053
Author(s):  
Jian Bing Guo ◽  
Kai Zhou Zhang

Poly (ethylene 1-octene) (POE) was functionalized to varying degrees with maleic anhydride (MA) by melt grafting processes. Fourier transform infrared spectra (FT-IR) confirmed that maleic anhydride was successfully grafted onto the POE. The POE-g-MAH elastomers were used to toughen Polybutylene terephthalate(PBT). The mechanical properties, morphology and the dispersal phase size were investigated. Results showed that the grafting degree strongly influenced the morphology, mechanical properties and the dispersal phase size. All results in this paper were consistent, and showed good interaction between POE and PBT, which was proven by the mechanical properties of blends.


2011 ◽  
Vol 25 (6) ◽  
pp. 271-285 ◽  
Author(s):  
Tao Hu ◽  
Wen-Ying Jin ◽  
Cun-Gui Cheng

Fourier transform infrared spectroscopy (FT-IR) with Horizontal Attenuated Total Reflectance (HATR) techniques is used to obtain the FT-IR spectra of five kinds of mosses, such asPtychomitrium dentatum(Mitt.) Jaeg.,Ptychomitrium polyphylloides(C. Muell.) Par.,Ptychomitrium sinense(Mitt.) Jaeg.,Macromitrium syntrichophyllumTher. Etp. Vard., andMacromitrium ferrieiCard. Sz Ther. Based on the comparison of the above mosses in the FT-IR spectra, the region ranging from 4000 to 650 cm−1was selected as the characteristic spectra for analysis. Principal component analysis (PCA) and cluster analysis are considered to identify the five moss species. Because they belong to the homogeneous plants, and have similar chemical components and close FT-IR spectroscopy, PCA and cluster analysis can only give a rough result of classification among the five moss species, Fourier self-deconvolution (FSD) and discrete wavelet transform (DWT) methods are used to enhance the differences between them. We use these methods for further study. Results show that it is an excellent method to use FT-IR spectroscopy combined with FSD and DWT to classify the different species in the same family. FT-IR spectroscopy combined with chemometrics, such as FSD and DWT, can be used as an effective tool in systematic research of bryophytes.


2020 ◽  
Vol 859 ◽  
pp. 39-44
Author(s):  
Yin Yin Myat ◽  
Nway Nway Aung ◽  
Tanasait Ngawhirunpat ◽  
Theerasak Rojanarata ◽  
Praneet Opanasopit ◽  
...  

The aim of this study was to develop a thermal crosslinkable microneedle (MN) array. Gantrez S-97 was employed as the MN-forming polymer. The MNs were successfully fabricated by micromolding method. The MNs were thermally crosslinked at different times (0.5, 1, 2, 3 h) and temperatures (110, 130, 150°C). The morphology of the MN was observed using a digital microscope. The successful crosslink was confirmed by Fourier transform infrared spectroscopy. The percentages of swelling and MN remaining after being soaked in water were also investigated. Fully formed, sharped MN with desirable morphology was obtained at the Gantrez S-97 concentration of 30 %w/v. The FT-IR spectra confirmed the successful crosslink of the MN. The crosslinked Gantrez MN arrays could absorb massive amount of water, and exhibited excellent swelling capability. Increasing the crosslinking time and temperature resulted in the decrease in the swelling capability but increase in the water insolubilization. The MNs crosslinked at 150°C for 3 h demonstrated almost hundred percent of water insolubilization which desirable for developing hydrogel-forming MN. Therefore, 30% w/v Gantrez S-97 MN could be crosslinked by thermal process, and could provide desirable swelling properties and percentage of water insolubility, and therefore, may be an alternative for fabrication of hydrogel-forming MN for transdermal drug delivery.


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