• Food Science and Biotechnology
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• v.18 no.5
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• pp.1199-1203
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• 2009

Melamine is a chemical intermediate to manufacture amino resins and plastics, which cannot be used as food additive since it can cause kidney stones. A qualitative determination method of melamine residue in powdered and liquid milk was developed using Fourier transform infrared (FTIR) spectroscopic technique. The calibration sets consisted of 21 standard melamine solutions, in which 1% trichloroacetic acid aqueous solution and acetonitrile (3:1, v/v) were used as solvent. The model was validated using 10 standard melamine solutions which were unused to build up the calibration set. Infrared (IR) absorbance peaks specific to almost all chemical groups in melamine molecule were shown in the spectral range between 1,100 and 1,800/cm. Combined partial least squares (PLS)-$2^{nd}$ derivative calibration model coupled with mean centering (MC) mathematical enhancement showed the highest correlation coefficients ($R^2$>0.99). In brief, the FTIR technique can be used for quantitative analysis of melamine in milk samples.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.4
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• pp.10-17
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• 2007

FTIR(Fourier Transform Infrared) spectrometry is a useful method to obtain infrared spectra of materials in gas phase by registering the interferogram of a target material using an interferometer, and then performing a Fourier transform on the interferogram to obtain the spectrum. In this paper, sampling noise effect on signal processing of the rapid scan interferometer was studied with relation to sampling the interferogram points at the improper location and empirically verified.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.1
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• pp.8-14
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• 2014

Brightness temperature spectra acquired from FTIR(Fourier Transform Infrared)-SCADS (Standoff Chemical Agent Detection System) could be available for detection and identification of the chemical agents and pollutants from different background. IR spectrum range of 770 to 1350 $cm^{-1}$ is corresponding to "atmospheric window". A 2-dimensional(2D) brightness temperature spectrum was drawn from combining each data point through automatic continuous scanning of FTIR along with altitude and azimuth. At higher altitude, temperature of background was decreased but scattering effect of atmospheric gases was increased. Increase in temperature difference between background and blackbody in SCADS at higher temperature causes to increases in peak intensity of $SF_6$. This approach shows us a possibility that 2D visual information is acquired from scanning data with a single FTIR-SCADS.

• Animal Bioscience
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• v.35 no.7
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• pp.1048-1058
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• 2022

Objective: The present study was to investigate the extraction conditions of dietary fiber from dried cassava pulp (DCP) and cassava distiller's dried grains (CDG) under different NaOH concentrations, and the Fourier transform infrared (FTIR) was used to determine the dietary fiber components. Methods: The dried samples (DCP and CDG) were treated with various concentrations of NaOH at levels of 2%, 4%, 6%, and 8% using a completely randomized design with 4 replications of each. After extraction, the residual DCP and CDG dietary fiber were dried in a hot air oven at 55℃ to 60℃. Finally, the oven dried extracted dietary fiber was powdered to a particle size of 1 mm. Both extracted dietary fibers were analyzed for their chemical composition and determined by FTIR. Results: The DCP and CDG treated with NaOH linearly or quadratically or cubically (p<0.05) increased the total dietary fiber (TDF) and insoluble fiber (IDF). The optimal conditions for extracting dietary fiber from DCP and CDG were under treatment with 6% and 4% NaOH, respectively, as these conditions yielded the highest TDF and IDF contents. These results were associated with the FTIR spectra integration for a semi-quantitative analysis, which obtained the highest cellulose content in dietary fiber extracted from DCP and CDG with 6% and 4% NaOH solution, respectively. The principal component analysis illustrated clear separation of spectral distribution in cassava pulp extracted dietary fiber (DFCP) and cassava distiller's dried grains extracted dietary fiber (DFCDG) when treated with 6% and 4% NaOH, respectively. Conclusion: The optimal conditions for the extraction of dietary fiber from DCP and CDG were treatment with 6% and 4% NaOH solution, respectively. In addition, FTIR spectroscopy proved itself to be a powerful tool for fiber identification.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.5
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• pp.395-402
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• 2004

We need to develop technology of identifying high temperature high pressure(HTHP) synthetic diamond and HTHP treated natural diamonds from untreated natural diamonds to cope with sophisticated diamond enhancing technology. We had successfully identified synthetic diamonds using a vibrating sample magnetometer due to their ferromagnetic property. In addition, we identified the HTHP enhanced TypeIa, TypeIIa diamonds by employing non-destructive Fourier Transform Infrared(FTIR) spectroscopy.

• Journal of Magnetics
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• v.21 no.4
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• pp.599-602
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• 2016

Fluoride (F) is an important element for the mineralization of body tissues. The purpose of this study was to administer fluoride prenatally to rats to evaluate its beneficial concentration for rat bone using microstructural analysis, to analyze its effect on the bone structure, and to evaluate the effect of its transfer through rat placenta. Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectrometry (NMR) were performed. The $^{19}F$ NMR and $^{31}P$ NMR signals suggested the existence of fluoride ions in the apatite lattice because the signals were caused by the fluoride ions that were coupled to the phosphate atoms and were affected in the phosphate phases other than the element phases in the apatite. Consequently, if it was not affected too much, the desirable concentration of prenatal fluoride treatment could have a helpful effect on the bone crystal structure through placental fluoride transfer.

• Bulletin of the Korean Chemical Society
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• v.28 no.9
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• pp.1588-1590
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• 2007

• Journal of the Korean Society of Hazard Mitigation
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• v.5 no.4 s.19
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• pp.79-84
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• 2005

When polymeric materials are exposed to fire condition, a lot of heat and toxic gases evolved and cause damage to property and human being. Especially toxic gases are major hazard to life safety. This study FTIR(Fourier Transform Infrared) spectrometer analysis was performaed to etermine the gas analysis and the concentration of gases evolved from PVC, FRP, SMC and Ureathane foam using ASTM E 1678 fire model. And FED toxicity index calculated from FTIR data also presented. By the comparison of animal test adopted in KS F 2271 and FTIR gas analysis method, FTIR gas analysis method can replace current animal toxicity test and produce precise and quantitative combustion gas data.

• The Journal of Advanced Prosthodontics
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• v.12 no.2
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• pp.61-66
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• 2020

PURPOSE. The aim of the present study was to determine the degree of conversion of light- and dual-cured resin cements used in the cementation of all-ceramic restorations under different thicknesses of translucent (T) and high-translucent (HT) polymer-infiltrated ceramic-network (PICN) material. MATERIALS AND METHODS. T and HT PICN blocks were prepared at 0.5, 1.0, 1.5, and 2.0 mm thicknesses (n=80). Resin cement samples were prepared with a diameter of 6 mm and a thickness of 100 ㎛. Light-cured resin cement was polymerized for 30 seconds, and dual-cure resin cement was polymerized for 20 seconds (n=180). Fourier transform infrared spectroscopy (FTIR) was used for degree of conversion measurements. The obtained data were analyzed with ANOVA and Tukey HSD, and independent t-test. RESULTS. As a result of FTIR analysis, the degree of conversion of the light-cured resin cement prepared under 1.5- and 2.0-mm-thick T and HT ceramics was found to be lower than that of the control group. Regarding the degree of conversion of the dual-cured resin cement group, there was no significant difference from the control group. CONCLUSION. Within the limitation of present study, it can be concluded that using of dual cure resin cement can be suggested for cementation of PICN material, especially for thicknesses of 1.5 mm and above.

• Bulletin of the Korean Chemical Society
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• v.17 no.9
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• pp.826-830
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• 1996

Fourier transform infrared (FTIR) temperature studies were performed to examine the microstructural changes that occur in annealing process of the thin films of 1,2-polybutadiene (1,2-PBu)/palladium chloride (PdCl2) complex. The disappearance of the infrared absorption intensities at 1640, 1418, 994 and 910 cm-1 signifies the consumption of 1,2-vinyl groups of 1,2-PBu. The progressive loss of unsaturation and production of methyl groups as a function of temperature were identified by the enhanced infrared absorption intensities at 1447 and 1375 cm-1. The loss of pendent carbon-carbon double bond is considered to involve both palladium-catalyzed addition reaction and thermally induced cyclization.