• Current Optics and Photonics
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• 제1권3호
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• pp.247-251
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• 2017

In this study, an ultraviolet Raman spectrometer was designed and fabricated to detect chemical contamination on the ground. The region of the Raman spectrum that indicated the characteristics of the chemicals was $350-3800cm^{-1}$. To fabricate a Raman spectrometer operating in this range, the layout and angle of optical components of the spectrometer were designed using a grating equation. Experimental devices were configured to measure the Raman spectra of chemicals based on the fabricated Raman spectrometer. The wavenumber of the spectrometer was calibrated by measuring the Raman spectrum of polytetrafluoroethylene, $O_2$, and $N_2$. The spectral range of the spectrometer was measured to be 23.46 nm ($3442cm^{-1}$) with a resolution of 0.195 nm ($30.3cm^{-1}$) at 253.65 nm. After calibration, the main Raman peaks of cyclohexane, methanol, and acetonitrile were found to be similar to the references within a relative error of 0.55%.

• 폴리머
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• 제26권6호
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• pp.745-751
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• 2002

본 연구에서는 시료의 형광문제를 제거한 FT-Raman spectrometer을 이용하여 연신된 syndiotactic polypropylene의 비등방적 Raman 산란 특성을 측정하였다. 관찰된 Raman 피크를 해석하여 해당 symmetry species 분류를 목적으로, 입사 및 산란 복사선의 편광방향이 서로 다른 4 가지 편광실험을 수행하여 스펙트럼을 얻었다. 이 편광 Raman 실험 결과를 편광 infrared 실험에 의한 dichroism 결과 및 진동운동의 이론적 계산인 normal coordinate analysis 결과와 비교 분석하였다.

• 한국연소학회지
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• 제1권2호
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• pp.9-20
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• 1996

We construct a mobile broadband coherent anti-Stokes Raman spectroscopy system to measure the temperature of combustion gases. To improve the accuracy of CARS temperatures due to Stokes lasers, a modeless dye laser is constructed. A monochromator to disperse CARS spectra is also constructed in the spectrometer for easy portability. The accuracy of CARS temperature, measured in graphite tube furnace in reference to a radiation pyrometer, is better than 2 % from 1000 K to 2400 K. The CARS temperature error due to the variation of the spectral distribution of the modeless laser is measured to be less than 1.5 % during five hours operation. As a demonstration of combustion diagnosis, we applied the spectrometer to measure the temperature distribution of the propane air premixed flame.

• 한국광학회지
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• 제24권3호
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• pp.143-147
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• 2013

라만 분광기는 그래핀의 특성을 분석하기 위한 필수적인 방법이다. 상용 마이크로 라만 분광기는 작은 면적에 대해 유용하게 사용되고 있으나 작은 면적 측정으로 인하여 산업적으로는 시료 측정 등에 제한적으로 사용되고 있다. 본 논문에서는 그래핀의 대면적 이미지 얻을 수 있는 라만 분광기에 대해 제안하였다. 이 이미지를 이용하여 그래핀의 유무 및 결함에 대한 정보를 빠르게 얻었다. 이를 이용하여, 실시간으로 그래핀에 대한 결함 유무, 층 수에 대한 균일도를 확인할 수 있으며, 양산 그래핀에 대한 품질 평가에 활용할 수 있을 것이다.

• 한국군사과학기술학회지
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• 제22권3호
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• pp.433-440
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• 2019

In order to detect toxic chemical spread on field ground, we developed stand-off Raman spectrometer system which employed a deep UV laser. In this paper, the design and specification of various components in the spectrometer system are described. Some results when the detection system was tested on the outdoor roads are shown, which may help researching stand-off chemical detectors based on Raman spectroscopy.

• 한국광학회:학술대회논문집
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• 한국광학회 1989년도 제4회 파동 및 레이저 학술발표회 4th Conference on Waves and lasers 논문집 - 한국광학회
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• pp.59-64
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• 1989

Raman vibrational Q0branch spectra of pure CO are measured by using the technique of quasicw inverse Raman spectroscopy utilizing a pulsed single-frequency laser source. This approach gives enhanced sensitivity compared to earlier work which employed CW lasers, allowing extension of that work to higher accuracy, higher J states, and higher pressure. Fitting laws with pertubation theory and modified energy gap(MEG) theory are described, and the line broadening and shifting coefficients of J=0 to 24 are determined with both fitting laws.

• 한국재료학회지
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• 제15권12호
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• pp.786-790
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• 2005

We investigated the particularity of temperature and composition changes in $xNa_2O{\cdot}(52.5-x)B_2O_3{\cdot}47.5SiO_2$ glasses by use of FT-IR, $^{11}B$ NMR, Raman spectrometer. From FT-IR and $^{11}B$ NMR spectrometer, we thought that tetrahedral boron, $BO_4$ units are created $N_4$ increasing tendency generated near $600^{\circ}C$. It's expected that composition ana heat treatment directly contributed to structural changes, this changes are following to $Na_2O$ increasing or decreasing. caused by $N_4\;and\;BO_4$ units are caused by relatively increasing or decreasing in the glasses' structure. Particularly, $BO_4$ units are converted to $BO_3$ units after $600^{\circ}C$ heat treatment for 50h in the composition of $x<18(R<0.5,\;R=Na_2O/B_2O_3\;mol\%)$. On the order hand, $BO_3$ units are converted to, $BO_4$ units after $600^{\circ}C$ heat treatment for 50h in the composition of $x{\geq}18\;(R>0.5)$. This particularity of composition and temperature dependence of structural changes are similarly represented by Raman analysis results.

• 대한금속재료학회지
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• 제50권1호
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• pp.23-27
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• 2012

The color of a natural diamond that contains nitrogen impurities can be enhanced by a high pressure high temperature (HPHT) treatment. Type IaAB diamond samples containing nitrogen impurities were executed by HPHT process of 5.6 Gpa, 10 min by varying the annealing temperature at 1600, 1650, and $1700^{\circ}C$. Property characterization was carried out using an optical microscope, FT-IR spectrometer, low-temperature PL spectrometer, and micro Raman spectrometer. By observing optical micrographs, it can be seen that diamond sample began to alter its color to vivid yellow at $1700^{\circ}C$. In the FT-IR spectrum, there were no Type changes of the diamond samples. However, amber centers leading to brown colors lessened after $1700^{\circ}C$ annealing. In the PL spectrum, all the H4 centers became extinct, while there were no changes of yellow color center H3 before or after treatment. In the Raman spectrum, no graphite spots were detected. Consequently, diamond color enhancement can be done by higher than $1700^{\circ}C$ HPHT annealing at 5.6 GPa-10 min.

• 한국멀티미디어학회논문지
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• 제12권12호
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• pp.1755-1760
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• 2009

In this research, for the first time, we tried to analyse Raman hyperspectral dentin data using Independent Component Analysis (ICA) to see its possibility of adoption for the dental analysis software. We captured hyperspectral dentin data on 569 spots on a molar with dental lesion by HR800 Micro Raman Spectrometer at UMKC-CRISP (University of Missouri at Kansas City-Center for Research on Interfacial Structure and Properties). Each spot has 1,005 hyperspectral data. We applied ICA to the captured hyperspectral data of dentin for evaluating ICA approach, and compared it with the well known multivariate analysis method, PCA. As a result of the experiment, ICA approach shows better local characteristic of dentin than the result of PCA. We confirmed that ICA also could be a good method along with PCA in the dental analysis software.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.660-662
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• 2005

본 연구에서는 미 인근 해저에서 ODP로 확인된 부존 하이드레이트 샘플을 다양한 분광학 및 실험적 분석 방법을 통해 시료의 물성 및 특성을 파악하여 부존된 하이드레이트 자원의 성분 파악을 목적으로 하고 있다. 일반적으로 가스 하이드레이트 연구에 있어서 X-ray diffractometer, NMR stectrometer, Raman spectrometer 등 분광학적 분석기기를 이용하여 가스 하이드레이트의 구조 및 성분을 규명한다. 본 연구에서는 실험실에서 인위적으로 만들어진 메탄 하이드레이트와 심해저 천연가스 하이드레이트 층에서 채취된 샘플의 비교 분석을 통하여 심해에 매장되어 있는 천연가스 하이드레이트의 구조 및 성분을 규명하였다 XRD 결과로부터 천연가스 하이드레이트는 sI의 구조를 가지며 NMR 및 Raman 결과에 의하면 하이드레이트 내에 포집되어 있는 가스의 주 성분은 메탄인 것으로 밝혀졌다. 또한 천연가스 하이드레이트를 이용한 이산화탄소의 치환 실험을 통하여 심해저 천연가스 하이드레이트 층의 이산화탄소 저장 매체로의 활용 가능성을 조사하였다.