• 제목/요약/키워드: Fluorescence spectra

검색결과 306건 처리시간 0.022초

Target Transformation Factor Analysis에 의한 겹침 X-선 형광 스펙트라의 정량적 해석 (A Quantitative Interpretation of the Overlapped X-Ray Fluorescence Spectra by Target Transformation Factor Analysis)

  • 김승원;이철;최상원;강형태
    • 대한화학회지
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    • 제36권5호
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    • pp.720-726
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    • 1992
  • 겹쳐 나타나는 X-선 형광 스펙트라에서 얻은 다변수 데이타를 해석하기 위하여 다변수분석법인 인자분석법을 적용하였다. Pb와 As의 피크가 겹쳐 있는 11개 표준시료의 X-선 형광 스펙트라를 파장분산형기기로 $33.50∼34.50^{\circ}$에서 측정하였다. 8개 시료의 피크세기로 데이타 매트릭스를 구성하고 AFA(Abstract Factor Analysis)를 수행하였다. 그 결과 인자의 수가 3으로 나타났으며 표준시료에 함유된 8개 원소를 타겟트 테스트한 결과 Pb, As 및 Cu로 판명되었다. 농도 기지인 시험시료에서 상기 원소들의 농도를 피크의 겹침에 무관하게 TTFA(Target Transformation Factor Analysis)에 의해 결정하였다.

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자외선 유도 형광의 사과 성숙도 평가 적용 (UV/blue Light-induced Fluorescence for Assessing Apple Quality)

  • 노현권
    • Journal of Biosystems Engineering
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    • 제35권2호
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    • pp.124-131
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    • 2010
  • Chlorophyll fluorescence has been researched for assessing fruit post-harvest quality and condition. The objective of this preliminary research was to investigate the potential of fluorescence spectroscopy for measuring apple fruit quality. Ultraviolet (UV) and blue light was used as an excitation source for inducing fluorescence in apples. Fluorescence spectra were measured from 'Golden Delicious' (GD) and 'Red Delicious' (RD) apples using a visible/near-infrared spectrometer after one, three, and five minutes of continuous UV/blue light illumination. Standard destructive tests were performed to measure fruit firmness, skin and flesh color, soluble solids and acid content from the apples. Calibration models for each of the three illumination time periods were developed to predict fruit quality indexes. The results showed that fluorescence emission decreased steadily during the first three minutes of UV/blue light illumination and was stable within five minutes. The differences were minimal in the model prediction results based on fluorescence data at one, three or five minutes of illumination. Overall, better predictions were obtained for apple skin chroma and hue and flesh hue with values for the correlation coefficient of validation between 0.80 and 0.90 for both GD and RD. Relatively poor predictions were obtained for fruit firmness, soluble solids content, titrational acid, and flesh chroma. This research has demonstrated that fluorescence spectroscopy is potentially useful for assessing selected quality attributes of apple fruit and further research is needed to improve fluorescence measurements so that better predictions of fruit quality can be achieved.

하·폐수 처리시설 내 유입수 특성이 유기물 처리효율에 미치는 영향 (Effects of the Characteristics of Influent Wastewater on Removal Efficiencies for Organic Matters in Wastewater Treatment Plants)

  • 이태환;박민혜;이보미;허진;양희정
    • 한국물환경학회지
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    • 제25권5호
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    • pp.674-681
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    • 2009
  • Characteristics of organic matters (OM) in wastewater and the removal efficiencies were investigated using the influent and the effluent samples collected from 21 wastewater treatment plants. The OM characteristics investigated included biodegradability, humic content, specific UV absorbance (SUVA), the distribution percentage of refractory OM (R-OM), and synchronous fluorescence spectra. The types of wastewater (sewage, livestock waste/night soils, industrial waste) were easily distinguished by comparing the synchronous fluorescence spectra of the influent wastewater. The prominent peak of protein-like fluorescence (PLF) was observed for livestock waste/night soils whereas sewage exhibited a unique fluorescence peak at a wavelength of 370 nm. Irrespective of the wastewater types, the distribution percentage of R-OM increased from the influent to the effluent. Livestock waste/night soils showed the highest removal efficiency among all the three types of wastewater. There was no statistical difference of the removal efficiency between a traditional activated sludge and biological advanced treatment processes. Removal efficiency based on dissolved organic carbon DOC presented good correlations with the distribution percentage of R-OM and fulvic-like fluorescence (FLF) of the influent. The prediction for DOC removal efficiency was improved by using multiple regression analyses based on some selected OM characteristics and mixed liquid suspended solid (MLSS).

Using Hyperspectral Fluorescence Spectra of Deli Commodities to Select Wavelengths for Surveying Deli Food Contact Surfaces

  • Lefcourt, Alan M.;Beck, Elizabeth A.;Lo, Y. Martin;Kim, Moon S.
    • Journal of Biosystems Engineering
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    • 제40권2호
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    • pp.145-152
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    • 2015
  • Purpose: The inability to adequately judge the efficacy of cleaning and sanitation procedures in deli departments is a recognized food safety concern. In a prior study, our research group demonstrated that visual inspection of cleaned produce processing surfaces could be enhanced through the use of a portable fluorescence imaging device that detected residual produce residues. Methods: To explore the feasibility of using fluorescence imaging to similarly detect residual deli residues, spectra of American, Cheddar, Provolone, and Swiss cheeses and of processed chicken, ham, roast beef, and turkey were acquired using a laboratory hyperspectral imaging system. Circular punches of these commodities were placed onto stainless steel and high density polyethylene coupons for imaging. The coupon materials were selected to represent common surfaces found in deli departments. Results: Analysis of hyperspectral fluorescence images showed that cheeses exhibited peaks in the blue-green region and at around 675 nm. Meats exhibited peaks in the blue-green region with one of four ham and one of four chicken brands exhibiting peaks at around 675 nm, presumably due to use of plant-derived additives. When commodities were intermittently imaged over two weeks, locations of spectral peaks were preserved while intensity of peaks at shorter wavelengths increased with time. Conclusion: These results demonstrate that fluorescence imaging techniques have the potential to enhance surface hygiene inspection in deli departments and, given the immediate availability of imaging results, to help optimize routine cleaning procedures.

속 이온과 CFP 상호작용: 흡수 형광 분광법에 의한 금속 이온과 CFP의 착물 형성 (Interaction of CFP with Metal ions: Complex Formation of CFP with Metal ion by Absorption and Fluorescence Spectrophotometery)

  • Siddiqi, K.S.;Mohd, Ayaz;Khan, Aftab Aslam Parwaz;Bano, Shaista
    • 대한화학회지
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    • 제53권2호
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    • pp.152-158
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    • 2009
  • 산성 용액에서 $Ca^{2+},\;Mg^{2+},\;Mn^{2+},\;Fe^{3+},\;Co^{2+},\;Ni^{2+},\;Cu^{2+}$$Zn^{2+}$와 Cefpodoxime proxetil (CFP)의 상 호작용을 분광학적으로 조사한 결과 1:1 착물이 형성됨을 알 수 있다. 순수한 약품의 흡수스펙트럼은 270과 345 nm에서 두 개의 현저한 봉오리를 보였다. 여러 pH에서 스펙트럼은 두 개의 isosbestic 점(305 과 330 nm)을 나타내었다. 이는 용액상에서 약품의 쯔비터 이온이 존재함을 의미한다. 다른 농도의 금 속이온에서 CFP의 형광방출 스펙트럼은 chelating enhancement fluorescence(CHEF)효과에 의해 형광강 도가 증가함을 알 수 있었다. 착체의 화학량론은 Job’'s 와 Benesi-Hildebrand 방법에 의해 결정되었다. 착 체의 안정도는 다음 순서와 같다. $Ca^{2+}\;<\;Mg^{2+}\;<\;Co^{2+}\;<\;Ni^{2+}\;<\;Zn^{2+}\;<\;Mn^{2+}\;<\;Cu^{2+}\;<\;Fe^{3+}$.

Application of Laser-Induced Fluorescence for EDC monitoring in aquatic system

  • Ko Eun-Joung;Kim Kyoung-Woong
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
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    • pp.117-121
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    • 2005
  • In order to monitor the levels and seasonal variations of EDCs, samples of the discharged effluent from sewage & wastewater treatment plants and river waters were collected. The target EDCs including bisphenol A and alkylphenols were determined by Laser-induced fluorescence(LIF) as in-situ monitoring technique. The category of EDCs showed similar fluorescence spectra and nearly equal decay time. This point makes it hard to distinguish each EBCs from the EDCs mixture by LIF and LIF results were expressed only by the total EDCs. However, LIF monitoring results and GC-MS results was comparable. The correlation coefficient between EDCs concentration acquired from GC-MS and fluorescence intensity from LIF was significant. This study supports the feasibility of the application of LIF into EDCs monitoring In aquatic system.

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방사선 치료에서 광학적 생검의 유용성에 관한 연구 (The Study of Optical Biopsy‘s Usefulness in Radiotherapy)

  • 강승희;한승희;;;강해진
    • 한국의학물리학회지:의학물리
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    • 제12권1호
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    • pp.9-17
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    • 2001
  • 본 논문의 목적은 조직(Tissue)에서의 광학적 특성(Optical Properties)을 이용한 광학적 생검(Optical Biopsy)방법을 소개하고, 방사선 치료에서 치료 반응 결과를 확인하는데 적당한 도구인가를 확인하고자 한다 본 연구는 구강(Oral Cavity) 내부조직을 샘플로, 건강한 사람 4명과 구강 암환자 4명의 자원을 받았다. 연구실에서 제작한 FastEEM(Excitation Emission Matrix) 장비를 이용하여 생체 내(in vivo)상태에서 측정하였다. 건강한 구강의 정상조직(Normal Tissue)과 병이 있는 구강의 비정상조직에서 기존의 생검과 동시에 새로운 광학적 생검을 하였다. 광학적 생검 결과와 기존의 생검 결과를 비교 확인하고, 암 조직으로 진단 받은 환자들에게 2차 광학적 생검을 실시하였다. 암 조직에 대한 1차 광학적 생검과 2차 측정 결과에 대한 형광스펙트럼을 비교 분석하였고, 자료분석은 Gillenwater가 개발한 337nm에 근거한 진단 알고리즘을 이용하였다. 광학적 생검 방법은 암 조직을 정상조직과 확실하게 구분시키는 장비임을 확인하였다. 건강한 구강조직과 악성 종양 조직의 측정 형광세기를 비교하면 정상조직인 경우 암 조직의 형광세기보다 모든 환자에 대해서 크게 나타났다. 암 조직의 구성이 시간에 따라 변하였을 때(7일) 광학적 생검을 하면 측정된 4명의 환자의 형광의 세기에 변화가 있었다. 7일간 시간이 지난 암 조직이 형광세기가 더 작은 값을 갖는다. 광학적 생검은 조직을 인체에서 분리하지 않는 생체 내, 실시간, 비침습성(noninvasive)생검 방법이다. 본 연구에서는 구강의 정상조직과, 암 조직, 그리고 암 조직의 진화에 따른 구성의 변화를 형광스펙트럼으로 확인하였다. 형광분광법을 이용한 FastEEM장치는 암 조직의 변화를 확인함으로 방사선 치료 후 발생하는 암 조직 구성의 화학적, 생물학적, 형태학적 변화를 실시간으로 정확하게 측정이 가능한 장치임을 확인하였다.

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Determination of Heparin Using Norfloxacin-cerium Complex as a Fluorescence Probe by Spectrofluorimetry

  • Patil, Shailaja R.;Mote, Umesh S.;Patil, Shivajirao R.;Kolekar, Govind B.
    • Bulletin of the Korean Chemical Society
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    • 제30권12호
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    • pp.3034-3038
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    • 2009
  • A simple, rapid, practical and sensitive spectofluorimetric method was developed for the determination of trace amount of heparin (Hep). Under the Optimum conditions, we studied the interaction between NFLX-Ce$^{3+}$-Hep complex by using absorption and fluorescence spectra. It was observed that Hep remarkably enhance the fluorescence intensity of the NFLX-Ce$^{3+}$ complex at ${\lambda}$= 356 nm in the buffer solution of pH = 7.60 and the enhancement effect is shown to relate with the concentration of Hep. The linear range and detection limit for the determination of Hep was obtained. By the Rosenthal graphic method, the association constant (K) and binding numbers (N) of Hep with probe were investigated. This method is relatively free of interference from coexisting substances and successfully applied for the determination of heparin in heparin sodium injection samples. A suitable mechanism of fluorescence enhancement between NFLX-Ce$^{3+}$ and the NFLX-Ce$^{3+}$-Hep systems were proposed and discussed.

변색 효과 보석들의 분광학적 특성 (Spectroscopic Characteristics of Gemstones with Color Change Effect)

  • 안용길;서진교;박종완
    • 한국광물학회지
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    • 제22권2호
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    • pp.81-86
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    • 2009
  • 변색 효과를 보이는 6종의 보석들을 대상으로 UV-Vis 분광분석과 Photoluminescence에 의한 발광 및 형광 특성을 조사하였다. 514 nm Ar이온 source로 PL을 측정한 결과 발광 피크의 모양이 다르게 나타났고 같은 천연과 합성 보석에서는 동일한 피크가 나타났다. 이들 발광 및 형광 특성은 보석들의 결정 구조와 관련이 있음을 관찰할 수 있었다. 325 nm He-Cd source에 의한 형광 조사에서는 합성 알렉산드라이트와 합성 칼라체인지 사파이어 그리고 천연 알렉산드라이트에서 강한 형광이 나타났고 이를 PL 피크로 확인하였다.