• Title/Summary/Keyword: Spectroscopy

Search Result 10,081, Processing Time 0.185 seconds

Electrochemical and Spectroscopic Studies on the Interaction between DNA and the Product of Enzyme-catalyzed Reaction of OPD-H2O2-HRP

  • Niu, S.Y.;Zhang, S.S.;Ma, L.B.;Jiao, K.
    • Bulletin of the Korean Chemical Society
    • /
    • v.25 no.6
    • /
    • pp.829-832
    • /
    • 2004
  • The pure product of 2,3-diaminophenazine was prepared by the enzyme-catalyzed reaction of ophenylenediamine-$H_2O_2$-horseradish peroxidase and characterized by UV/Vis spectroscopy, IR spectroscopy and NMR spectroscopy. The electrochemical behaviour of 2,3-diaminophenazine on the glassy carbon electrode was studied. The interaction between 2,3-diaminophenazine and deoxyribonucleic acid was studied by cyclic voltammetry method and UV/Vis spectroscopy, which indicated that the interaction between them is intercalation. The influence of reacting time was also studied. The binding ratio of the 2,3-diaminophenazine-DNA complex is calculated to be 1 : 2 and the binding constant is to be $5.07{\times} 10^3L{\cdot}mol^{-1}$ at room temperature.

Optical Interferometry as Electrochemical Emission Spectroscopy of Metallic alloys in Aqueous Solutions

  • Habib, K.;AI-Mazeedi, H.
    • Corrosion Science and Technology
    • /
    • v.2 no.6
    • /
    • pp.277-282
    • /
    • 2003
  • Holographic interferometry, an electromagnetic method, was used to study corrosion of carbon steel, aluminum and copper nickel alloys in NaOH, KCI and $H_2SO_4$ solutions respectively. The technique, called electrochemical emission spectroscopy, consisted of in-situ monitoring of changes in the number of fringe evolutions during the corrosion process. It allowed a detailed picture of anodic dissolution rate changes of alloys. The results were compared to common corrosion measurement methods such as linear polarization resistance measurements and electrochemical impedance spectroscopy. A good agreement between both data was found, thus indicating that holographic interferometry can be a very powerful technique for in-situ corrosion monitoring.

Applications of Near Infrared Reflectance Spectroscopy(NIRS) in Forage Evaluation (조사료 가치 평가를 위한 근적외선 분광법(NIRS)의 활용)

  • 박형수;이종경;이효원
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.24 no.1
    • /
    • pp.81-90
    • /
    • 2004
  • Farmers need timely information on the nutritional status of their animals and the nutritive value of pastures and supplementary feeds if they are to apply successfully this existing nutritional information. Near infrared reflectance(NIR) spectroscopy has been used over the last forty years to analyse accurately protein, fiber, and other organic components in animal foods. NIR spectroscopy is a rapid, non-destructive, and non-polluting technology. When properly calibrated, NIR spectroscopy is used successfully with both concentrate and forage feeds. NIR methods predict in vitro digestibility accurately and precisely, and can predict in vivo digestibility at least as well as conventional "wet chemistry" methods such as in vivo digestion or the pepsin-cellulase method, and much more rapidly. NIR technology has been applied to the routine monitoring (through analysis of feces samples) of the nutritional status of cattle and other grazing animals. This report reviews the use of near infrared reflectance(NIR) spectroscopy to monitor the nutritive value of animal feeds and the nutritional status of grazing animals.

Identification for the Vivid Yellow Diamonds (비비드 옐로우 다이아몬드의 감별 방안 연구)

  • Song, Jeongho;Yun, Yury;Song, Ohsung
    • Journal of the Korean Ceramic Society
    • /
    • v.49 no.6
    • /
    • pp.493-497
    • /
    • 2012
  • We propose a new reliable, fast, and low cost identification method for similarly looking 0.3ct vivid yellow color of natural, HPHT treated, and synthesized diamonds. Conventional optical microscopy as well as low temperature PL(photoluminescence), FT-IR, UV-VIS-NIR, micro-Raman spectroscopy, and vibrating sample magnetometry(VSM) characterization were executed. We could not distinguish the natural diamonds from the treated or the synthesized stones with an optical microscopy, PL, FT-IR, and UV-VIS-NIR spectroscopy. However, we could identify the treated diamond with micro-Raman spectroscopy due to unique $1440cm^{-1}$ peak appearance. VSM revealed easily the synthesized diamond because of its ferromagnetic behavior. Our preliminary propose on employing the Micro-Raman spectroscopy and VSM might be suitable for identification of the similar looking vivid yellow colored diamonds.

Neutron and gamma-ray energy reconstruction for characterization of special nuclear material

  • Clarke, Shaun D.;Hamel, Michael C.;Di fulvio, Angela;Pozzi, Sara A.
    • Nuclear Engineering and Technology
    • /
    • v.49 no.6
    • /
    • pp.1354-1357
    • /
    • 2017
  • Characterization of special nuclear material may be performed using energy spectroscopy of either the neutron or gamma-ray emissions from the sample. Gamma-ray spectroscopy can be performed relatively easily using high-resolution semiconductors such as high-purity germanium. Neutron spectroscopy, by contrast, is a complex inverse problem. Here, results are presented for $^{252}Cf$ and PuBe energy spectra unfolded using a single EJ309 organic scintillator; excellent agreement is observed with the reference spectra. Neutron energy spectroscopy is also possible using a two-plane detector array, whereby time-of-flight kinematics can be used. With this system, energy spectra can also be obtained as a function of position. Spatial-dependent energy spectra are presented for neutron and gamma-ray sources that are in excellent agreement with expectations.

Blood Glucose Measurement Principles of Non-invasive Blood Glucose Meter: Focused on the Detection Methods of Blood Glucose (무채혈 혈당 측정기의 혈당 측정 원리: 혈당 검출방법 중심으로)

  • Ahn, Wonsik;Kim, Jin-Tae
    • Journal of Biomedical Engineering Research
    • /
    • v.33 no.3
    • /
    • pp.114-127
    • /
    • 2012
  • Recent technical advancement allows noninvasive measurement of blood glucose. In this literature, we reviewed various noninvasive techniques for measuring glucose concentration. Optical or electrical methods have been investigated. Optical techniques include near-infrared spectroscopy, Raman spectroscopy, optical coherence technique, polarization, fluorescence, occlusion spectroscopy, and photoacoustic spectroscopy. Electrical methods include reverse iontophoresis, impedance spectroscopy, and electromagnetic sensing. Ultrasound, detection from breath, or fluid harvesting technique can be used to measure blood glucose level. Combination of various methods is also promising. Although there are many interesting and promising technologies and devices, there need further researches until a commercially available non-invasive glucometer is popular.

Coherent Control of Autler-Townes Splitting in Photoelectron Spectroscopy: The Effect of Laser Intensity and Laser Envelope

  • Qin, Chaochao;Zhai, Hongsheng;Zhang, Xianzhou;Liu, Yufang
    • Bulletin of the Korean Chemical Society
    • /
    • v.35 no.11
    • /
    • pp.3294-3298
    • /
    • 2014
  • We theoretically investigated the coherent control of Autler-Townes splitting in photoelectron spectroscopy of K2 molecule within an ultrafast laser pulse by solving the time-dependent Schrodinger equation using a quantum wave packet method. It was theoretically shown that we can manipulate the splitting of photoelectron spectroscopy by altering the laser intensity. Furthermore, it was found that the percentages of each peak in photoelectron spectroscopy can be controlled by changing the envelope of the laser pulse.

Chamber Monitoring with Residual Gas Analysis with Self-Plasma Optical Emission Spectroscopy

  • Jang, Hae-Gyu;Lee, Hak-Seung;Park, Jeong-Geon;Chae, Hui-Yeop
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • /
    • pp.262.2-262.2
    • /
    • 2014
  • Plasma processing is an essential process for pattern etching and thin film deposition in nanoscale semiconductor device fabrication. It is necessary to maintain plasma chamber in steady-state in production. In this study, we determined plasma chamber state with residual gas analysis with self-plasma optical emission spectroscopy. Residual gas monitoring of fluorocarbon plasma etching chamber was performed with self-plasma optical emission spectroscopy (SPOES) and various chemical elements was identified with a SPOES system which is composed of small inductive coupled plasma chamber for glow discharge and optical emission spectroscopy monitoring system for measuring optical emission. This work demonstrates that chamber state can be monitored with SPOES and this technique can potentially help maintenance in production lines.

  • PDF

Identification of Irradiated Fishes by ESR Spectroscopy (방사선 조사 어류의 ESR Spectroscopy를 이용한 확인)

  • 님혜선;우시호;이선영;양재승
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.29 no.3
    • /
    • pp.425-429
    • /
    • 2000
  • 본 연구는 ESR spectroscopy를 이용하여 어류의 방사선 조사 여부와 조사선량에 따른 ESR 신호의 크기 및 신호의 안정성을 확인하였다. 실험결과 방사선 조사된 어류는 g1=2.003$\pm$0.001과 g2=1.998$\pm$0.003에서 특유의 비대칭적인 ESR 신호를 나타내어 비조사시료와 확실하게 구별되었다. 조사선량의 증가에 따른 ESR 신호의 상관성에 있어서는 R2값이 0.9077~0.9989의 범위로 거의 모든 시료에서 조사선량에 따라 ESR 신호의 크기는 비례적으로 증가하였다. 또한 이들 신호의 크기는 5$^{\circ}C$에서 12주간 저장한 시료에서도 안정하게 남아 있어 방사선 조사여부의 판별은 장기간의 저장에서도 가능하였다. 따라서 ESR spectroscopy를 이용한 방사선 조사 어류의 검지 방법은 빠르고 확실하며 반(semi) 정량적인 방법으로써 유용한 검지기술임을 알 수 있었다.

  • PDF

Development of Spectroscopy Toolkit for Spectrum Measurement Experiments Using a CsI(Tl)/PIN Diode Detector

  • Nam, Young-Mi;Kim, Han-Soo;Ha, Jang-Ho;Lee, Jae-Hyung
    • Journal of Radiation Protection and Research
    • /
    • v.35 no.2
    • /
    • pp.77-80
    • /
    • 2010
  • The spectroscopy toolkit has been developed and tested. The toolkit consists of a CsI(Tl)/PIN diode detector, integrated electronics, and a multi.channel.analyzer and its size was 40 cm(width) by 20 cm(length) by 6 cm(high). It is compact, very portable and simpler and cheaper compared to the conventional spectroscopy system. The gamma energy resolutions of the toolkit were 7.9% for the 660 keV of $^{137}Cs$ and 4.9% for 1,332 keV of $^{60}Co$ respectively. The linearity for gamma energies was good. When the energy spectrum of a ceramic sample containing $^{232}Th$ was measured with the spectroscopy toolkit for 20 minutes, there were significant peaks of the heavy metal. These results show that the resolution of the spectroscopy toolkit is sufficient to accumulate a quality spectrum in a few minutes by using weak, encapsulated commercial sources. Furthermore a toolkit experiment that how to measure energy spectra using the toolkit, and how to identify specific isotopes in a pottery piece, could be widely adopted for education and even for more sophisticated and higher level experiments.