• Title/Summary/Keyword: FT-IR

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FT-IR and X-Ray Diffraction Characterization of Melanoidins Formed from Glucose and Fructose with Amino Acid Enantiomers in the Maillard Reaction

  • Kim, Ji-Sang;Lee, Young-Soon
    • Food Science and Biotechnology
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    • v.18 no.2
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    • pp.546-551
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    • 2009
  • The objective of this study was to investigate Fourier transform infrared (FT-IR) spectrometry and the X-ray diffraction (XRD) characterization of melanoidins formed from glucose and fructose with amino acid enantiomers in the Maillard reaction. Before dialysis, FT-IR spectroscopy of all the samples showed that the characteristic absorption intensities appeared as a broad and intense band of the stretching vibration of the -OH group at 3,400/cm for a high pH. The absorption bands of the melanoidins sharply decreased in intensity after dialysis as compared to those before dialysis. In particular, the absorption bands at 992 and 575/cm disappeared. The XRD confirmed that the crystal structure of the melanoidins disappeared after dialysis and a new crystal structure was formed at 9 and $28^{\circ}$ ($2{\theta}$. In particular, broad diffraction peaks were formed in the $10-21^{\circ}$ ($2{\theta}$) range for a high pH, while other sharp diffraction peaks disappeared.

Properties of the Natural and CVD Synthetic Diamonds for Identification (천연과 CVD 합성 다이아몬드의 감별을 위한 물성 연구)

  • Kim, Yunwoo;Song, Jeongho;Noh, Yunyoung;Song, Ohsung
    • Journal of the Korean Ceramic Society
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    • v.51 no.4
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    • pp.350-356
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    • 2014
  • Recently, Chemical Vapor Deposition (CVD) synthetic diamonds have been introduced to the jewelry gem market, as CVD technology has been making considerable advances. Unfortunately, CVD diamonds are not distinguishable from natural diamonds when using the conventional gemological characterization method. Therefore, we need to develop a new identification method that is non-destructive, fast, and inexpensive. In our study, we employed optical microscopy and spectroscopy techniques, including Fourier transform infra-red (FT-IR), UV-VIS-NIR, photoluminescence (PL), micro Raman, and cathodoluminescent (CL) spectroscopy, to determine the differences between a natural diamond (0.30 cts) and a CVD diamond (0.43 cts). The identification of a CVD diamond was difficult when using standard gemological techniques, UV-VIS-NIR, or micro-Raman spectroscopy. However, a CVD diamond could be identified using a FT-IR by the Type II peaks. In addition, we identified a CVD diamond conclusively with the uneven UV fluorescent local bands, additional satellite PL peaks, longer phosphorescence life time, and uneven streaks in the CL images. Our results suggest that using FT-IR combined with UV fluorescent images, PL, and CL analysis might be an appropriate method for identifying CVD diamonds.

A Synthesis of Spherical Shape $TiO_2-SiO_2$ Complex via Solvothermal Process and Thermal Properties at Non-Isothermal (용매열합성을 이용한 구형 $TiO_2-SiO_2$ 복합체 제조 및 열적특성)

  • Cho Tae-Hwan;Park Seong-Jin
    • Journal of the Microelectronics and Packaging Society
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    • v.12 no.2 s.35
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    • pp.141-147
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    • 2005
  • Nanomaterial $TiO_2-SiO_2$ was synthesized by hydrolysis and condensation process using 2-propanol(2-PrOH) and was characterized by FT-IR, DSC, XRD and FE-SEM. FT-IR spectra were measured to investigate Ti-0-Si absorption peak. DSC thermal analysis results appllied to Ozawa equation were used to calculate to activation energy of crystallization. It was found that the changes of X-ray diffraction patterns and FWHM obtained XRD measurement depended on calcination temperature. In FE-SEM analysis, particle size changed by quantity changes of Ti-alkokide.

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Change of Heating Value, pH and FT-IR Spectra of Charcoal at Different Carbonization Temperatures

  • Kwon, Sung-Min;Jang, Jae-Hyuk;Lee, Seung-Hwan;Park, Sang-Bum;Kim, Nam-Hun
    • Journal of the Korean Wood Science and Technology
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    • v.41 no.5
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    • pp.440-446
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    • 2013
  • To understand transition characteristics from wood to charcoal, Quercus variabilis wood was carbonized at 200, 250, 300, 340, 540 and $740^{\circ}C$, respectively. Heating value, pH and surface property by FT-IR spectroscopy of the carbonized charcoal were investigated. Heating value and pH increased with increasing carbonization temperature from 4500 cal/g and 4.3 of the control wood to 8,000 cal/g and 9 of the charcoal carbonized at $740^{\circ}C$, respectively. From FT-IR spectroscopy, the peaks from O-H, C-H and C-O stretching disappeared during carbonization at 540 and $740^{\circ}C$. Aromatic skeletal vibration at near $1,506{\sim}1,593cm^{-1}$ was repidly increased until $540^{\circ}C$. These results suggest that the chemical and physical characteristics of wood components in cell wall can be easily changed by increasing carbonization temperature and the carbonization seem to be incomplete at temperature below $540^{\circ}C$.

Spectroscopic Analysis of the Remote-plasma-polymerized Methyl Methacrylate Film (원격 플라즈마 중합된 메틸메타크릴레이트 필름의 분광학적 분석)

  • Seomoon, Kyu
    • Applied Chemistry for Engineering
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    • v.32 no.1
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    • pp.49-54
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    • 2021
  • Plasma-polymerized methyl methacrylate (MMA) thin films were synthesized by remote plasma, and effects of plasma power, reaction pressure and direct-indirect plasma on the growth rate and chemical bonding were investigated with alpha-step, FT-IR, XPS and Langmüir probe method. As the plasma power and pressure increased, the tendency of growth rate showed maximum value at a certain range. FT-IR and XPS analyses revealed that composition ratio of C/O and hydrocarbon (C-C) % in the deposited films increased with plasma power, but ester (COO) C % decreased with it. Direct plasma method was effective for fast growth rate, but indirect plasma method was favorable for maintaining the chemical structure of MMA.

Characteristics study on fire-resistant paint used by TGA-IR (TGA-IR을 사용한 내화 도료의 특성에 관한 연구)

  • Cho, Nam-Wook;Shin, Hyun-Jun;Cho, Won-Bo;Lee, Seong-Hun;Rie, Dong-Ho;Kim, Hyo-Jin
    • Analytical Science and Technology
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    • v.24 no.3
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    • pp.168-172
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    • 2011
  • The iron frame of building could be collapsed or bent at $500^{\circ}C$. Therefore the fire-resistant paint should be applied for safety. This study performed the comparative analysis to show the characteristics of fireresistant paint. And then 12 products of fire resistant paint and 6 products of paints were used as samples. And the samples were analyzed by TGA (Thermogravimetric Analyzer) as analyzer for measuring the variation of weight on temper of weight by heating. When TGA analyzer could measure the variatiature, and FT-IR was measured for analyze gas components on variation on of weight by heating on 12 products of fire resistance, the samples showed to decrease 40% of weight to $800^{\circ}C$, and because paints had 50% to 40% of loss weight, it showed to be equal with loss weight of fire resistance paint on high temperature or was lower loss weight than it of fire resistance paints. However number 6 sample of fire resistance paints could show to decrease 20% of total weight on $800^{\circ}C$. And then in the case of FT-IR, fire resistance paints could show to have the high intensity of $CO_2$ spectrum as complete combustion. However paints could show to have the lower intensity of $CO_2$ spectrum, have the higher intensity of water spectrum. Therefore the TGA graph of result could be much different until $250^{\circ}C$. When it was burned, FT-IR spectrum could show to confirm the characteristics of fire resistance paints, and the characteristic could be confirmed on inorganic paint of fire resistance by weight loss of TGA.

Construction and Measurement of Normal Spectral Emissivity Device using Fourier Transform Infrared Spectrometer (퓨리에 변환 적외선 분광기를 이용한 수직 분광 복사율 측정 장치의 제작과 측정)

  • Jeon, Sang-Ho;Yoo, Nam-Joon;Jo, Jae-Heung;Park, Chul-Woung;Park, Seung-Nam;Lee, Geun-Woo
    • Korean Journal of Optics and Photonics
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    • v.19 no.6
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    • pp.400-407
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    • 2008
  • An Instrument to measure normal spectral emissivity is built using a Fourier Transform-Infrared (FT-IR) spectrometer. The instrument is composed of four main parts, reference blackbody, sample furnace, optics system, and FT-IR spectrometer. Measurement ranges of temperature and wavelength are $200^{\circ}C{\sim}500^{\circ}C$ and $3.5{\mu}m{\sim}20{\mu}m$, respectively. Measured emissivity of the reference blackbody is greater than 0.9993 with combined relative uncertainty less than 0.69%, which can be considered an ideal blackbody. We studied the emissivity of opaque alumina, graphite, anodized aluminum, and steel (IMS 200). It is shown that emissivity increases with the roughness of the steel (IMS 200) surface.

Preparation and Characterization of La0.8Ca0.2MnO3 (La0.8Ca0.2MnO3의 합성 및 특성연구)

  • 정미원;이지윤;김현정
    • Journal of the Korean Ceramic Society
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    • v.40 no.5
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    • pp.434-440
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    • 2003
  • The powders of L $a_{0.8}$C $a_{0.2}$Mn $O_3$ Colossal Magnetoresistance (CMR) materials were synthesized by sol-gel process. Lanthanum(H), Calcium(II) and Manganese(III) 2,4-Pentanedionate were dissolved in a mixed binary solution consisted of propionic acid and methanol with PEG (15 wt%) aqueous solution. The progress of reactions was monitored by FT-IR spectroscopy. The Lao scao.2Mn03 gel powders were annealed at various temperatures. The structural changes were investigated by FT-IR, CP/MAS $^{ 13}$C solid state NMR spectroscopy and XRD. The thermochemical property, particle characterization, microstructure of sintered sample, and cation composition of gel powder were studied by TG/DTA, FE-SEM and ICP-AES. The magnetic characterizations were identified through measurement of magnetic moment by VSM.

A Method for Absolute Determination of the Surface Areal Density of Functional Groups in Organic Thin Films

  • Min, Hyegeun;Son, Jin Gyeong;Kim, Jeong Won;Yu, Hyunung;Lee, Tae Geol;Moon, Dae Won
    • Bulletin of the Korean Chemical Society
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    • v.35 no.3
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    • pp.793-797
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    • 2014
  • To develop a methodology for absolute determination of the surface areal density of functional groups on organic and bio thin films, medium energy ion scattering (MEIS) spectroscopy was utilized to provide references for calibration of X-ray photoelectron spectroscopy (XPS) or Fourier transformation-infrared (FT-IR) intensities. By using the MEIS, XPS, and FT-IR techniques, we were able to analyze the organic thin film of a Ru dye compound ($C_{58}H_{86}O_8N_8S_2Ru$), which consists of one Ru atom and various stoichiometric functional groups. From the MEIS analysis, the absolute surface areal density of Ru atoms (or Ru dye molecules) was determined. The surface areal densities of stoichiometric functional groups in the Ru dye compound were used as references for the calibration of XPS and FT-IR intensities for each functional group. The complementary use of MEIS, XPS, and FT-IR to determine the absolute surface areal density of functional groups on organic and bio thin films will be useful for more reliable development of applications based on organic thin films in areas such as flexible displays, solar cells, organic sensors, biomaterials, and biochips.

Feasibility of Determining the Ripeness of Strawberry Fruit Flesh by Fourier Transform Infrared Spectroscopy (Fourier 변환 적외선 분광분석법에 의한 딸기 과육의 성숙도 측정 가능성)

  • Min, Sung-Ran;Kwak, Chul-Won;Kim, Suk-Weon;Jeong, Won-Joong;Chung, Hwa-Jee;Choi, Pil-Son;Ko, Suk-Min;Park, Sang-Kyu;Chung, Hoe-Il;Liu, Jang, R.
    • Journal of Plant Biotechnology
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    • v.33 no.4
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    • pp.277-281
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    • 2006
  • Fourier transform - infrared spectroscopy (FT-IR) provides biochemical profiles containing overlapping signals from a majority of the compounds that are present when whole cell extracts are analyzed. We attempted to determine the ripeness of strawberry fruit flesh by FT-IR. Fruit ripeness was divided into four developmental stages based on fruit skin color: 'yellow-green', 'pink-green', 'pink', and 'red' stages. Principal component analysis of FT-IR data of inside fruit flesh extracts clustered samples of four different developmental stages into three discrete groups: (1) 'yellow-green' group, (2) 'pink-green' group, and (3) 'pink' and 'red' group. The most remarkable difference between four different developmental stages was found in the carbohydrate fingerprint region $(1,000-1,100cm^{-1})$ of the FT-IR spectrum, indicating that differences in carbohydrate compounds represented the ripeness of strawberry fruit. Overall results indicate that FT-IR in combination with PCA enables discrimination of the ripeness of strawberry fruit flesh.