• 제목/요약/키워드: spectroscopic method

검색결과 527건 처리시간 0.028초

HPHT(고온고압)에 의해 처리된 type IIa 천연 다이아몬드의 감별에 관한 연구 (A study on the identification of type IIa natural diamonds treated by the HPHT method)

  • 김영출;최현민
    • 한국결정성장학회지
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    • 제14권1호
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    • pp.21-26
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    • 2004
  • HPHT(고온고압) 처리된 type IIa 다이아몬드의 분광분석 결과를 나타내었다. 그리고 HPHT 처리된 다이아몬드 spectrum의 특성을 이와 유사한 color와 type을 가진 처리되지 않은 다이아몬드와 비교하였다. 325nm 에서 여기된 He/Cd laser로는 HPHT 처리된 다이아몬드와 처리되지 않은 다이아몬드에 현저한 변화가 있음을 알 수 있었는데 이는 HPHT 처리된 다이아몬드의 spectrum에서 H3, H4에 관련된 peak가 제거되고 N3 system에 관련된 peak의 emission이 증가함을 보여 주었다. 또한 514nm에서 여기된 Ar-ion laser로 측정된 spectrum은 575nm와 637.1 nm에서 Nitrogen과 vacancy가 관련되어있는 N-V center가 발견 되었는데 이러한 center가 존재하고 있을 경우 637.1 nm의 FWHM의 값은 HPHT 처리된 다이아몬드와 처리되지 않은 다이아몬드를 구분할 수 있음을 보여주었다. 본 실험에서 측정된 HPHT 처리된 다이아몬드의 637.1nm $(N-V)^-$의 FWHM 값은 $19.8{\textrm}{cm}^{-1}$에서$32.1{\textrm}{cm}^{-1}$였다.

Emission Plasma Spectroscopy of High-pressure Microdischarges

  • 이병준;주영도;김승환;하태균;공형섭;박용정;박종도;남상훈
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.253.2-253.2
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    • 2014
  • Micro hollow cathode discharges (MHCDs) are high-pressure, non-equilibrium discharges. Those MHCDs are useful to produce an excimer radiation. A major advantage of excimer sources is their high internal efficiency which may reach values up to 40% when operated under optimum conditions. To produce strong excimer radiation, the optimisation of the discharge conditions however needs a detailed knowledge of the properties of the discharge plasma itself. The electron density and temperature influence the excitation as well as plasma chemistry reactions and the gas temperature plays a major role as a significant energy loss process limiting efficiency of excimer radiation. Most of the recent spectroscopic investigations are focusing on the ultraviolet or vacuum ultraviolet range for direct detection of the excimer. In our experiments we have concentrated on investigating the micro hollow cathodes from the near UV to the near infrared (300~850 nm) to measure the basic plasma parameters using standard plasma diagnostic techniques such as stark broadening for electron density and the relative line intensity method for electron temperature. Finally, the neutral gas temperature was measured by means of the vibrational rotational structures of the second positive system of nitrogen.

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Layer-by-Layer 자기조립법에 의한 Poly(ethyiene-alt-maleic anhydride)i Poly(4-vinyl pyrtdine) 다층막 제조 (Fabrication of an Alternating Multilayer Film of Poly(ethylene-alt-maleic anhydride) and Poly(4-vinyl pyridine) by Layer-by-Layer Self-Assembly Method)

  • 이준열;홍숙영
    • 폴리머
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    • 제29권4호
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    • pp.392-398
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    • 2005
  • Layer-by-layer(LbL) 흡착에 의한 poly(ethylene-alt-m미? anhydride) (PEMAh)/poly(4-vinyl pyridine) (P4VP) 자기조립 다층박막을 제조하였다. 자기조립 다층막을 이루는 PEMAh/P4VP 두 고분자 사이의 수소 결합과 정전기적 인력이 다층막을 이루는 원동력이라는 것이 푸리에 변환 적외선(FT-IR) 분광분석에 의해서 확인되었다. 다층막의 균일한 자기조립 과정은 PEMAh/P4VP 이중층막의 적층 수 증가에 따른 UV-vis 스펙트럼의 256 nm에서 나타나는 P4VP 특성 흡수 피크의 선형적 증가에 의해서 확인할 수 있었다. 다층막을 이루는 고분자 전해질 담지 용액의 조건 변화가 다층막 형성에 미치는 영향을 살펴보기 위하여 두 고분자 용액의 농도 및 PEMAh 담지용액의 pH를 변화시키면서 다층막을 제조하였다. 다층막의 두께, 흡착된 고분자 전해질 질량 및 표면 거칠기의 변화를 UV-vis 분광 분석, 수정진동자 미량저울(quartz crystal microbalance;QCM) 및 원자 힘 현미경(atomic force microscopy;AFM)을 이용하여 측정하였다.

Sterols Isolated from Nuruk (Rhizopus oryzae KSD-815) Inhibit the Migration of Cancer Cells

  • Lee, Dae-Young;Lee, Sang-Jin;Kwak, Ho-Young;Jung, La-Koon;Heo, Ji-Eun;Hong, Sung-Youl;Kim, Gye-Won;Baek, Nam-In
    • Journal of Microbiology and Biotechnology
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    • 제19권11호
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    • pp.1328-1332
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    • 2009
  • An activity-guided fractionation method was used to isolate anticancer components from Nuruk (Rhizopus oryzae KSD-815:KSD-815). Dried powder of KSD-815 was extracted with 80% methanol and partitioned successively using n-hexane, ethyl acetate, n-butanol, and water. The n-hexane and n-butanol fractions showed a strong antimigratory effect on human cancer cells. Both of these fractions were subjected to separation and purification procedures using silica gel, octadecyl silica gel, and Sephadex LH-20 column chromatographies to afford four purified compounds. These were identified as ergosterol peroxide (1), stigmast-5-en-$3\beta$,$7\beta$-diol (2), ergosta-7,22-dien-$3\beta$,$5\alpha$,$6\beta$,$9\alpha$-tetraol (3), and daucosterol (4), respectively, by spectroscopic methods such as nuclear magnetic resonance spectrometry, mass spectrometry, and infrared spectroscopy, and comparison with those in the literature. Compounds 1-4 were isolated from KSD-815 for the first time. Compounds 1 and 4 inhibited the migration of MDA-MB-231 cells at concentrations lower than $20\;{\mu}M$.

현미 자외/가시광선영역 분광광도계에 의한 미세시료의 분석 (Identification of the Trace Evidence by UV/VIS Microspectrophotometry)

  • 손성건;박하선;이진숙;박성우;조성희
    • 분석과학
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    • 제13권2호
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    • pp.250-257
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    • 2000
  • 페인트, 섬유, 잉크 등은 범죄현장에 유류되는 많은 증거물 중 가장 빈번하게 접하게 되는 법과학 증거물로서 이들에 대한 분석 결과는 범죄현장과 피해자 또는 피의자, 피해자와 피의자간의 상황 재구성 및 인과관계, 도주 용의 차랑 등의 추적에 결정적인 역할을 하고 있다. 그러나 이들 시료는 육안으로 거의 확인이 되지 않을 만큼 극미량의 미세한 시료가 대부분이므로 법과학분야에서 미세시료에 대한 체계적인 분광학적 분석법이 대두되고 있다. 본 연구에서는 현미 자외/가시광선 현미분광광도계를 이용하여 섬유 14종, 국내 자동차 차체 페인트 2개 색상 44종 및 3개 회사의 컬러 프린트용 잉크로 인쇄한 4개 색상 12종에 대해 자외선/가시광선 영역(240-780nm)에서 투과 및 반사 측정법으로 측정하였으며, 각각 특징적인 흡수대로 섬유, 페인트 및 잉크의 이동식별이 가능하였다.

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자외선 형광 분석법을 이용한 유류 토양오염 모니터링 시스템의 현장 적용을 위한 기초 연구 (Laboratory-scale fluorescence spectroscopic method using UV for monitoring soils contaminated with petroleum produce)

  • 김우진;박재우;이주인
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제7권4호
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    • pp.48-58
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    • 2002
  • 본 연구는 자외선-형광분석법을 이용한 유류저장시설의 모니터링 시스템의 현장 적용성에 관한 기초 실험으로서, 선행연구에서 사용하였던 샘플들의 실제 오염상황을 충분히 반영하지 못하는 한계점을 보완하였다. 선행연구에서 보다 측정의 신뢰도를 높이기 위하여 오염이 발생하여 이동하고 감지되어지는 실제 상황을 고려한 형광 측정 실험을 수행하였다. 또한 자연환경의 영향을 보기 위하여 수분 함량에 따른 형광의 세기를 비교한 결과 수분에는 큰 영향을 받지 않고, 측정시의 토양의 상태에 좌우된다고 사료된다. 마지막으로 안정적인 오염도 측정값을 얻기 위하여 시스템에 이용할 대표성을 갖는 표준 토양을 결정하기 위한 실험을 수행하였다. 이를 위해 모래와 칼슘-벤토나이트(Ca-bentonite), 연마용 모래를 실험했으며, 이외에도 여러 가지 단일물질들을 테스트하였으나 모래를 제외한 다른 물질들은 시스템에 적용하기엔 한계점이 있었다 그러나 모래는 자체 형광이 낮아 형광 측정에 영향을 적게 미치며, 누구나 쉽게 구할 수 있는 장점과 더불어 오염도에 따른 형광이 비교적 안정적이어서 시스템의 감지부에 넣어줄 표준 토양으로 이용하기에 적합하다고 사료된다.

변성 폴리아크릴 아미드의 합성 및 제지공정의 보류시스템에 응용 (Synthesis of modified polyacrylamides and their applications for the retention system of papermaking)

  • 손동진;윤지현;최은정;김봉용
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2009년도 춘계학술발표회 논문집
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    • pp.23-28
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    • 2009
  • The purpose of this study was to improve not only wet-end performances but also paper characteristics by the modification of various factors like molecular design and ionic characteristics of polyacrylamides First of all physical characteristics were observed after modify molecular design of the cationic polyacrylamides to linear, branched and cross-linked. In addition it was found analysis method to confirm branch degree of cationic polyacrylamides to combine ionic titration characteristics and spectroscopic behavior, After application of these structure modified polyacrylamides to the multiple retention systems with inorganic microparticles, it was found adjusting of branch degree of polyacrylamides was very important to optimize wet-end improvement. Second, After polymerization of amphoteric polyacrylamide to have both of cationic and anionic functional group in the polymer, we observed not only physical characteristics but also wet-end improvement to apply recycled pulp and found that the improvement of solution stability to prevent hydrolysis and increase of ash retention dramatically to compare traditional cationic polyacrylamide retention aid, Finally, After polymerization of anionic polyacrylamide, we observed not only wet-end improvement but also paper characteristics to apply preflocculation of PCC and it was found the improvements of flocculation efficiency, retention, ash retention, optical properties of the paper and bursting strength to compare traditional preflocculant of cationic polyacrylamide.

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적외선(赤外線)(IR) 분광법(分光法)에 의한 고목재(古木材) 성상(性狀)의 심지(深知) (Application of Infrared Spectroscopical Techniques for Investigation of Archaeological Woods)

  • 김윤수
    • Journal of the Korean Wood Science and Technology
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    • 제16권4호
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    • pp.3-9
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    • 1988
  • Infrared (IR) spectroscopic techniques for the analysis of wood samples and the absorbance spectra of solid woods were presented. KBr pellets were prepared by throughly mixing approximately 300 mg of dried KBr and 1 mg of finely milled wood powder extracted with ethanol-cyclohexane previously. This mixture was made into a transparent disc by means of a pellet-making die (10 ton/$cm^2$ for 10 min). This IR techniques were applied for the analysis of archaeological wood samples. The most notable difference in the IR spectra between the recent and the archaeological waterlogged woods is that the absorption band centered at $1,730cm^{-1}$ was significantly diminished in the waterlogged ones. Total loss of absorption in $1,730cm^{-1}$ might be mainly due to the result of hemicellulose degradation. Another feature indicated by IR spectral comparision are that the degraded waterlogged wood samples showed 1) the increased intensity of the 1,600, 1,500 and $1,270cm^{-1}$ due to the residual lignin and the increased intensity at 1,470 and $1,425cm^{-1}$ due to the degradation of hemicellulose and 2) to the emergence of single band around $1,050cm^{-1}$ instead of three bands at 1,110, 1,060 and $1,040cm^{-1}$ in recent wood due to the degradation of cellulose crystalline. It was revealed from the IR examinations that the first change of wood in the waterlogged situation was the lysis of hemicellulose and the second the lysis of cellulose. It was also suggested that IR spectroscopy could serve a fast method for the investigation on the chemical characteristics of archaeological wood samples.

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떡윤노리나무로부터 분리된 Lyoniside의 함량분석과 항염증 효과 (Quantitative Analysis and Anti-inflammatory of Lyoniside from the Pourthiaea villosa var. brunnea)

  • 우경완;성태경;이혜미;장지훈;이기호;조현우;조정희;안병관
    • 생약학회지
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    • 제47권1호
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    • pp.12-17
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    • 2016
  • In this study, the purification of the MeOH extract from the stems and leaves of Pourthiaea villosa var. brunnea using column chromatography furnished a main compound, lyoniside. The structure was elucidated on the basis of $^1H$ and $^{13}C$ NMR spectroscopic data. Quantitative analysis of lyoniside was conducted by HPLC method and the highest content of lyoniside was found in 50% MeOH reflux extraction. To investigate the anti-inflammatory effect of the lyoniside, we measured nitric oxide and pro-inflammatory cytokines such as TNF-${\alpha}$, IL-$1{\beta}$, IL-6 levels in lipopolysaccharide-induced murine macrophage cell line RAW 264.7. As a results, lyoniside decreased the level of nitric oxide and IL-6 in concentration dose dependent manner in RAW 264.7 cells.

고비로부터 Cinnamtannin B-1의 분리 및 함량 분석 (Isolation and Quantitative Analysis of Cinnamtannin B-1 from Osmunda japonica Thunb)

  • 김민석;우경완;이기호;이현주;이선유;강병만;전병훈;조정희;조현우
    • 생약학회지
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    • 제47권3호
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    • pp.232-236
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    • 2016
  • In traditional Korean medicine, Osmunda japonica Thunb has been used as hemostasis and antipyretic treatment. The main compound "cinnamtannin B-1" was obtained by column chromatographic separation, and its structure was determined by spectroscopic methods, including $^1H$, $^{13}C$ NMR, and IT-TOF-ESI MS. Ash, moisture and extract content and acidinsoluble ash were monitored as identification test to establish the analytical methods. The optimum reflux extraction condition was 100% methanol extracted 30 min for 2 times. A quantitative analysis using HPLC method exhibited that the main compound at 24.7 min and its content was 0.96% in methanol extraction.