Fourier Transform Fluorescence Spectrometry

A variety of fluorescence spectra have been measured interferometrically, demonstrating the feasibility of Fourier Transform Fluorescence Spectrometry (FT-FS). Emission spectra have been measured with the use of a monochromatic source and an interferometer as the emission selector. Excitation spectra have been measured with the use of a multi-line laser. Fluorescence polarization spectra have also been recorded with the use of laser excitation. The analytical characteristics of working curves are discussed.

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Laser-induced fluorescence and discharge emission spectra of CrO. Rotational analysis of the A5Π–X5Π transition

Canadian Journal of Physics ◽

10.1139/p80-073 ◽

1980 ◽

Vol 58 (4) ◽

pp. 516-533 ◽

Cited By ~ 36

Author(s):

W. H. Hocking ◽

A. J. Merer ◽

D. J. Milton ◽

W. E. Jones ◽

G. Krishnamurty

Keyword(s):

Fluorescence Spectra ◽

Rotational Temperature ◽

Electronic States ◽

Emission Spectra ◽

Laser Induced Fluorescence ◽

Spin Orbit Coupling ◽

Excitation Spectra ◽

Large Numbers ◽

Parallel Polarization ◽

Indirect Information

The A5Π–X5Π electronic transition of CrO, near 6000 Å, has been analysed in detail using laser-induced fluorescence and conventional discharge emission spectroscopy. The transition provides the first instance where it has been possible to analyse the rotational structures of quintet electronic states completely. Although the parallel polarization of the transition has prevented the spin–orbit coupling and Λ-doubling intervals from being observed directly, it is shown that sufficient indirect information exists in the spectrum for them to be obtained with fair precision. The excited state, A5Π, is perturbed by large numbers of other electronic states which have no intensity of their own for emission to the ground state. The analysis of the perturbed regions has been greatly facilitated by the laser-induced fluorescence spectra: the excitation spectra correspond to a rotational temperature close to room temperature (which offers a significant improvement in resolution over the discharge spectra), and the J-assignments of the perturbed lines given by the resolved fluorescence spectra are unambigious

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Correction of Fluorescence Spectra

Applied Spectroscopy ◽

10.1366/000370294775269027 ◽

1994 ◽

Vol 48 (4) ◽

pp. 436-447 ◽

Cited By ~ 27

Author(s):

J. W. Hofstraat ◽

M. J. Latuhihin

Keyword(s):

Absorption Spectra ◽

Wavelength Range ◽

Fluorescence Spectra ◽

Fluorescence Emission ◽

Emission Spectra ◽

Wavelength Dependence ◽

Excitation Spectra ◽

Excitation Light ◽

Radiative Processes ◽

Sensing Applications

Several methods that can be applied to remove wavelength-dependent instrumental effects from fluorescence emission and excitation spectra have been investigated. Removal of such artifacts is necessary for the comparison of spectra that have been obtained on different instruments. Without correction, spectral line positions and relative intensities will be instrument-determined to a great extent. Furthermore, the application of adequate correction procedures provides excitation spectra which can be directly compared to absorption spectra; comparison of corrected excitation spectra and absorption spectra can be used to interpret the efficiency and pathways of radiative processes. Finally, corrected reflection spectra can be obtained, which can be directly transformed into absorption spectra and are useful for remote sensing applications. The methods that have been studied for the correction of emission spectra are the application of a standard lamp with calibrated spectral output and the use of fluorescence standards. The standards are a series of luminescent phosphors in polymer films and a solution of quinine sulfate dihydrate in perchloric acid, all provided with certified spectral emission values. For correction of excitation spectra, a quantum counter was applied. Several quantum counters were investigated. The best results were obtained for application of a mixture of the dyes basic blue and HITC, which provided good correction for the wavelength range 250 to 820 nm. No good quantum counters have been reported thus far for this (large) wavelength range. Correction for wavelength dependence of the excitation optics was realized by measurement of the excitation light intensity at the sample position and at the reference position with a Si photodiode. Correction factors for the excitation spectra were checked with a number of reference materials. Attention has also been paid to polarization-dependent effects that may occur in fluorescence spectra. The application of correction procedures was demonstrated for phytoplankton fluorescence spectra.

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Theoretical Study on Fluorescence Spectra of Three Coumarin Derivatives

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.389.25 ◽

2013 ◽

Vol 389 ◽

pp. 25-28 ◽

Cited By ~ 1

Author(s):

Ying Wang

Keyword(s):

Fluorescence Spectra ◽

Vibrational Analysis ◽

Emission Spectra ◽

Dft Method ◽

Excited Configuration ◽

Coumarin Derivatives ◽

Excitation Spectra ◽

Geometric Configurations ◽

Td Dft ◽

Experimental Values

The fluorescence spectra of three coumarin derivatives are studied. Geometric configurations of the three compounds are optimized by DFT method of quantum chemistry on B3LYP/6-31G. There is no imaginary frequency in vibrational analysis. Their excitation spectra are calculated by TD-DFT method. Furthermore, geometric configurations in excited state of the three compounds are optimized by CIS method. Based on the excited configuration emission spectra are also calculated. All the calculated results are in good agreement with experimental values.

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Factors influencing fluorescence spectra of free porphyrins.

Clinical Chemistry ◽

10.1093/clinchem/34.4.757 ◽

1988 ◽

Vol 34 (4) ◽

pp. 757-760 ◽

Cited By ~ 29

Author(s):

C F Polo ◽

A L Frisardi ◽

E R Resnik ◽

A E Schoua ◽

A M Batlle

Keyword(s):

Ionic Strength ◽

Fluorescence Spectra ◽

Emission Spectra ◽

Main Peak ◽

Excitation Spectra ◽

Fluorescence Excitation ◽

Experimental Conditions ◽

Organic Mixture ◽

Carbonate Buffer ◽

Factors Influencing

Abstract We recorded fluorescence excitation and emission spectra of uro- and coproporphyrin under different experimental conditions, to see how these conditions influence quantifications based on measurement of fluorescence intensity. We found that, for bands alpha and beta of the emission spectra and the main peak of the excitation spectra, fluorescence depends on pH and is minimal near pH 5 and near pH 7-7.5 for copro- and uroporphyrin, respectively. For band gamma of the emission spectra there was a constant decrease of fluorescence with increasing alkalinity of the solution. The intensity of porphyrin fluorescence also depends on ionic strength, reaching sharp maxima at 0.1 mol/L (for uroporphyrin) and 1 mol/L (for coproporphyrin). The organic mixture ethyl acetate:acetic acid (4:1 by vol), commonly used to extract porphyrins from biological samples, markedly diminishes the fluorescence of both porphyrins as compared with the same concentration of each porphyrin in aqueous acidic solvent. Furthermore, when we measured different ratios of uro:copro mixture at three distinct pHs and buffers, we found that at pH 10.5 (in carbonate buffer) the measured units of fluorescence depend only on total porphyrin concentration and not on the composition of the mixture.

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Automatic Discrimination of the Geographical Origins of Milks by Excitation-Emission Fluorescence Spectrometry and Chemometrics

Journal of Automated Methods and Management in Chemistry ◽

10.1155/2011/323196 ◽

2011 ◽

Vol 2011 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Lu Xu ◽

De-Hua Deng ◽

Chen-Bo Cai ◽

Hong-Wei Yang

Keyword(s):

Eastern China ◽

Emission Spectra ◽

Fluorescence Spectrometry ◽

Model Accuracy ◽

Excitation Spectra ◽

Quick Method ◽

Western Yunnan ◽

Time Required ◽

Analytical Time ◽

Total Accuracy

This paper presents the automatic discrimination of geographical origins of milks from Western Yunnan Plateau areas and eastern China by excitation-emission fluorescence spectrometry and chemometrics. Genuine plateau milks (n=60) and milks from eastern China (n=89) are scanned in the regions of 180–300 nm for excitation and 200–800 nm for emission. Different options of data analysis are investigated and compared in terms of their performance in discriminating milks of different geographical origins: (1) two-way partial least squares discriminant analysis (PLSDA) based on excitation and emission spectra, respectively; (2) two-way PLSDA based on fusion of excitation and emission spectra; (3) three-way PLSDA based on excitation-emission matrix spectra. The two-way PLSDA methods with excitation spectra, emission spectra, and fusion of excitation and emission spectra correctly classify 91.3%, 88.6%, and 95.3% of the milk samples, respectively; while the total accuracy of three-way PLSDA is 96.0%. The results demonstrate the two-way data combining excitation and emission spectra are sufficient to characterize and identify the plateau milks. Considering both model accuracy and the analytical time required, two-way PLS-DA with fusion of excitation and emission spectra is recommended as a reliable and quick method to discriminate plateau milks from ordinary milks.

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Excitation versus Emission Spectra as a Means to Examine Selective Fluorescence Quenching Agents

Applied Spectroscopy ◽

10.1366/0003702924123755 ◽

1992 ◽

Vol 46 (9) ◽

pp. 1388-1392 ◽

Cited By ~ 11

Author(s):

Sheryl A. Tucker ◽

William E. Acree

Keyword(s):

Fluorescence Quenching ◽

Spectral Data ◽

Emission Spectra ◽

Data File ◽

Excitation Spectra

To ascertain whether fluorescence quenching is best studied with the use of excitation or emission spectra, and to expand our existing PAH spectral data file, we have recorded excitation spectra of benzo[b]perylene, dibenzo[hi,wx]heptacene, tetrabenzo[de,hi,mn,qr]naphthacene, perylene, benzo[a]fluoranthene, benzo[def]indeno[1,2,3hi]chrysene, naphtho[2,1a]fluoranthene, naphtho[2,3b]fluoranthene, benzo[k]fluoranthene, 2-azapyrene, naphtho[8,1,2hij]pyreno[9,10,1def]phthalazine, indeno[1,-2,3ij]isoquinoline, benzo(lmn][3,8]phenanthroline, and 7-methyldibenzo(b,def]chrysene at various nitromethane concentrations. Results of these measurements verify our earlier observations concerning the nitromethane selective quenching rule and further illustrate the importance of considering inner-filtering artifacts in quenching studies.

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Synthesis and Characterization of Y2O3:Eu3+ Film Derived by Sol-Gel Processing

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.593 ◽

2007 ◽

Vol 336-338 ◽

pp. 593-596

Author(s):

Chun Yang ◽

Jun Ying Zhang ◽

Hai Bing Feng ◽

Wei Chang Hao ◽

Tian Min Wang

Keyword(s):

Raw Materials ◽

Sol Gel ◽

Emission Spectra ◽

Luminescent Properties ◽

Dip Coating ◽

Organic Additive ◽

Excitation Spectra ◽

Excitation Peak ◽

Close Relationship ◽

Dip Coating Technique

Y2O3:Eu3+ thin film was synthesized by sol-gel method with inorganic salt raw materials, and the crystal structure and luminescent properties were investigated. By adding organic additive to the sol, a homogeneous film with high luminescent intensity could be obtained by dip-coating technique on the surface of alumina sheet and quartz glass. Structures of the films were studied by XRD and SEM. The excitation spectra of the films showed a wide excitation peak from 200nm to 260nm, and the emission spectra had a strongest emission peak at 611nm which revealed a close relationship with the calcining temperature.

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The Synthesis and Electroluminescence Properties of 4-Benzofuranyl-1,8-Naphthalimide Derivatives

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.557-559.1031 ◽

2012 ◽

Vol 557-559 ◽

pp. 1031-1036 ◽

Cited By ~ 4

Author(s):

Jian Xin Yang ◽

Xiang Hui Wang

Keyword(s):

Absorption Spectra ◽

Fluorescence Spectra ◽

Cycloaddition Reaction ◽

Emission Spectra ◽

Luminescent Properties ◽

Quantum Yields ◽

Absorption And Fluorescence Spectra ◽

Maximum Brightness ◽

Maximum Emission ◽

Mild Conditions

A series of fluorescence compounds, 4-benzofuranyl-1,8-naphthalimides, were prepared through cycloaddition reaction from 4-ethynyl-1,8-naphthalimides and o-iodophenols which catalyzed by a Pd(PPh3)2Cl2 / CuI system under mild conditions. The intermediate material, 4-ethynyl-1,8- naphthalimide, was synthesized from 4-bromo-1,8- naphthalimide and trimethylsilyl- acetylene. The absorption and fluorescence spectra of 4-benzofuranyl-1,8- naphthalimides were studied and the quantum yields were measured. The maximum UV/vis absorption spectra were in the range of 375-400 nm and the maximum emission spectra were in the range of 470-510 nm. The electro- luminescent properties were also mensurated through a doped electroluminescent device which contains 1% 1,8-naphthalimides and 99% CBP (4,4'-N,N'-dicarbazole-biphenyl), It’s shown the maximum brightness reached 3700 cd/ m2 at 22.5V.

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