• Title/Summary/Keyword: Infrared(IR)

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Rapid Analysis of Melamine Content in Powdered and Liquid Milk Using Fourier Transform Infrared Spectroscopy

  • Wang, Jun;Jun, Soo-Jin;Li, Qing X.
    • 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.

Performance Improvement Technique of Long-range Target Information Acquisition for Airborne IR Camera

  • Yang, Hyun-Jin
    • Journal of the Korea Society of Computer and Information
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    • v.22 no.7
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    • pp.39-45
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    • 2017
  • In this paper, we propose three compensation methods to solve problems in high-resolution airborne infrared camera and to improve long-range target information acquisition performance. First, image motion and temporal noise reduction technique which is caused by atmospheric turbulence. Second, thermal blurring image correction technique by imperfect performance of NUC(Non Uniformity Correction) or raising the internal temperature of the camera. Finally, DRC(Dynamic Range Compression) and flicker removing technique of 14bits HDR(High Dynamic Range) infrared image. Through this study, we designed techniques to improve the acquisition performance of long-range target information of high-resolution airborne infrared camera, and compared and analyzed the performance improvement result with implemented images.

Absorptance and Electrical Properties Evaluation of Nickel Layer Deposited onto Thin Film Pyroelectric PZT IR Detector (PZT박막 적외선 감지소자의 적외선 흡수층으로 증착된 니켈 박막의 광학 및 전기적 특성 분석)

  • Ko, Jong-Soo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.28 no.11
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    • pp.1727-1732
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    • 2004
  • A nickel layer was deposited onto the PZT thin films, serving both as a selective radiation absorption layer and as a top electrode. The absorption properties of such nickel coated multi-layered infrared detectors were studied in the visible and infrared wavelength ranges. The optimal thickness of the nickel layer on our substrate was 10nm. The maximum absorption coefficient of the deposited 10nm thick nickel layer was 0.7 at a 632nm wavelength. However, a striking asymmetric polarization hysteresis loop was observed in these PZT thin films with nickel as the top electrode. This asymmetric polarization was attributed to the difference between the dynamic pyroelectric responses in these Ni/PZT/Pt films poled either positively or negatively before the measurement. A positively poled film showed a 40% higher voltage response than a negatively poled detector.

Infrared Absorption Spectroscopic Studies of ${\alpha},{\omega}$-Diphenylpolyenyl Anions with Odd Numbered Polyene Molecules

  • Kim, Jin Yeol;Kim, Eung Ryeol;Son, Dae Won
    • Bulletin of the Korean Chemical Society
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    • v.22 no.8
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    • pp.833-836
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    • 2001
  • Infrared absorption spectra of $\alpha\omega-diphenylpolyenyl$, anions Ph(CH)nPh- (DPn-, n=7, 9, and 13) in the tetrahydrofuran-d6 solutions was measured in the range of 1700 and 1200 cm-1 . The infrared spectra obtained from anions (DPn) showed considerable difference from their neutral species (DPn); their intensities were enhanced at least two orders of magnitude stronger than their neutral species. The in-plane CH bending modes at 1464 and 1375 cm-1 are correspondingly strengthened with the chain length increased, but the C=C stretching at 1541 cm-1 is weakened and frequencies are not changed. We provide an IR evidence for the first time that the bond order or bond alternations of the anions (soliton) are different from those of radical anions (polaron) as well as neutral species.

CO Observations Toward IRAS 07280-1829 and Its Related Clouds (적외선원 IRAS 07280-1829와 이와 관련된 분자운의 CO분자선 관측연구)

  • Lee, Chang-Won
    • Journal of the Korean earth science society
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    • v.32 no.4
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    • pp.402-410
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    • 2011
  • We present results of CO observations toward an infrared (IR) source, IRAS 07280-1829, and its possibly related molecular clouds. The physical parameters of this IR source such as its infrared slope (${\alpha}$=16) of the Spectral Energy Distribution and bolometric temperature (145 K) indicate that it is an embedded protostar. Its luminosity is ${\sim}2.9{\times}10^4L_{\odot}$, typical of a massive star. The CO profile toward IRAS 07280-1829 has broad wing components, implying a possible existence of CO outflow. The excitation temperature and mass of a molecular cloud (Cloud A) which is thought to harbor the IR source are estimated to be 9~22 K and ~180 $M_{\odot}$, respectively, indicating the Cloud A is a typical infrared-dark cloud. Its LTE mass is found to be much smaller than its virial mass by more than a factor of 10 which is inconsistent with the fact that a protostar recently formed exists in the Cloud A. This may suggest that the environment of the cloud where the IR source is forming is dominant of turbulence and/or magnetic filed, making its virial mass estimated unusually high.

Tension Behavior of Nicalon/CAS Ceramic Composites (Nicalon/CAS 세라믹 복합재료의 인장특성)

  • Kim, Jeong-Guk;Kim, Weon-Kyong
    • Proceedings of the KSME Conference
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    • 2004.11a
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    • pp.232-237
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    • 2004
  • The tension behavior of Nicalon/CAS glass-ceramic matrix composites was investigated. Infrared (IR) thermography was employed for two different types of $Nicalon^{TM}/CAS$ composites, i.e., cross-ply and unidirectional specimens. During tensile testing, an IR camera was used for in-situ monitoring of progressive damages of $Nicalon^{TM}/CAS$ samples. The IR camera provided the temperature changes during tensile testing. Microstructural characterization using scanning electron microscopy (SEM) was performed to investigate the fracture mechanisms of $Nicalon^{TM}/CAS$ composites. In this investigation, the thermographic NDE technique was used to facilitate a better understanding of the fracture mechanisms of the $Nicalon^{TM}/CAS$ composites during tensile testing.

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Comparison of Vinyl Acetate Contents of Poly(Ethylene-co-Vinyl Acetate) Analyzed by IR, NMR, and TGA

  • Kim, Eunha;Choi, Sung-Seen
    • Elastomers and Composites
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    • v.50 no.1
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    • pp.18-23
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    • 2015
  • Vinyl acetate (VA) contents of poly(ethylene-co-vinyl acetate) (EVA) analyzed by infrared spectroscopy (IR), nuclear magnetic spectroscopy (NMR), and thermogravimetric analysis (TGA) were compared. Four grade EVAs supplied by Aldrich Co. and four grade EVAs manufactured by DuPont Co. were used. For IR analysis, VA contents were determined using calibration curve (absorbance ratio of $1739cm^{-1}/2922cm^{-1}$ or $609cm^{-1}/1464cm^{-1}$) of reference EVAs. Correlation coefficients of the calibration curves were not sufficiently high ($r^2{\leq}0.96$). For NMR analysis, VA contents were determined using peaks of $CH_3$, $CH_2$, and CH. VA contents determined by NMR analysis were less than those marked by suppliers more than 10%. For TGA, VA contents were determined using weight loss through deacetylation. VA contents determined by TGA were slightly different with those marked by suppliers. Difference in the VA contents determined by different analytical methods was discussed, and difference in the analytical results according to the EVA suppliers was also examined.

Relation Between Flat-band Voltage and Quantum Efficiency of InSb MWIR Detector (InSb 중적외선 검출기의 Flat-band 전압과 양자효율의 상관관계)

  • Kim, Young-Chul;Eom, JunHo;Jung, Han;Kim, SunHo;Kim, NamHwan;Kim, Young-Ho
    • Journal of the Semiconductor & Display Technology
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    • v.17 no.2
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    • pp.12-15
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    • 2018
  • InSb (III-V compound semiconductor) is used for photodiode to detect the mid-wavelength infrared radiation. Generally the quantum efficiency of InSb IR FPAs(Focal Plane Arrays) is known to be determined by thickness of InSb and transmittance of anti-reflection coating layer. In this study, we confirmed that the C-V characteristics of detector array affects the quantum efficiency of the InSb IR FPAs. We fabricated the IR FPAs with various $V_{fb}$(flat band voltage) values and confirmed the tendency between the $V_{fb}$ value and quantum efficiency of the IR FPAs.

VTG based Moving Target Tracking Performance Improvement Method using MITL System in a Maritime Environment (해상환경에서 MITL 시스템을 활용한 VTG 기반 기동표적 추적성능 개선 기법)

  • Baek, Inhye;Woo, S.H. Arman
    • Journal of Korea Multimedia Society
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    • v.22 no.3
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    • pp.357-365
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    • 2019
  • In this paper, we suggest the tracking method of moving multi-objects in maritime environments. The image acquisition is conducted using IR(InfraRed) camera sensors on an airborne platform. Under the circumstance of maritime, the qualities of IR images can be significantly degraded due to the clutter influence, which directly gives rise to a tracking loss problem. In order to reduce the effects from the clutters, we introduce a technical approach under Man-In-The-Loop(MITL) system for enhancing the tracking performance. To demonstrate the robustness of the proposed approach based on VTG(Valid Tracking Gate), the simulations are conducted utilizing the airborne IR video sequences: Then, the tracking performances are compared with the existing Kalman Filter tracking techniques.

Evidence for Nitrogen-Bonded Acrylonitrile to Iridium (Ⅰ) in Acrylonitrilecarbonylbis(triphenylphosphine)iridium (Ⅰ) perchlorate

  • Park, Soon-Heum;Park, Hwa-Kun;Chin, Chong-Shik
    • Bulletin of the Korean Chemical Society
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    • v.5 no.4
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    • pp.167-169
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    • 1984
  • Analyses of $_1$H-NMR, infrared and electronic spectral data for $[Ir(CH_2 = CHCN)(CO)(P(C_6H_5)_3)_2]ClO_4 (1)$prepared by the reaction of $Ir(OClO_3)(CO)(P(C_6H_5)_3)_2$ with $CH_2 = CHCN$, agree with the suggestion that 1 is a mixture of the nitrogen-bonded acrylonitrile complex, $[(CO)(P(C_6H_5)_3)_2Ir-NCCH = CH_2]ClO_4$ and other compound which may be the C = C ${\Pi}$ -system-bonded acrylonitrile complex, "[(CO)(P(C6H5)3)2Ir-CHCN = CH2]ClO4.