Relevant bibliographies by topics / Excitation uv

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Excitation uv'

Author: Grafiati
Published: 4 June 2021
Last updated: 17 February 2022

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Journal articles on the topic "Excitation uv"

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OHTSUKA, Reiji. "UV and VUV Excitation Phoshors." JOURNAL OF THE ILLUMINATING ENGINEERING INSTITUTE OF JAPAN 82, Appendix (1998): 305. http://dx.doi.org/10.2150/jieij1980.82.appendix_305.

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Pokhrel, M., G. A. Kumar, C. G. Ma, M. G. Brik, Brian W. Langloss, Ian N. Stanton, Michael J. Therien, D. K. Sardar, and Yuanbing Mao. "Electronic and optical properties of Er-doped Y2O2S phosphors." Journal of Materials Chemistry C 3, no. 43 (2015): 11486–96. http://dx.doi.org/10.1039/c5tc02665b.

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Green light emitted from Y2O2S:1%Er phosphors after excited with NIR, UV and X-ray sources with emissions spectra under UV and NIR excitations (lower right) and X-ray excitation at different X-ray tube voltages (lower left).
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Librantz, André Felipe Henriques, Luiz Vicente Gomes Tarelho, Laércio Gomes, and Izilda Márcia Ranieri. "Study of UV fluorescences induced from 4f3 T 4f25d multistep absorptions of Nd3+ions in YLiF4 and LuLiF4 crystals." Exacta 4, no. 1 (March 12, 2008): 179–83. http://dx.doi.org/10.5585/exacta.v4i1.671.

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Nd3+ ultraviolet (UV) fl uorescence induced by multiphotonic laser excitations was studied in doped Nd:YLiF4 (YLF) and Nd:LuLiF4 (LLF) crystals by using the time resolved spectroscopy technique. The UV luminescences are due to transitions between the 4f25d and the 4f3 electronic confi gurations of Nd3+ ions. The 4f25d confi guration can be reached by direct pumping or by multiphotonic excitation, both processes give rise to the UV band emission with structure due to the strong phonon coupling expected for 5d orbital involvement in the transition. The multiphotonic excitation process is due to three photons (532 nanometers [nm]) sequential absorptions by metastable levels of the 4f3 confi guration split by crystalline local fi eld. The sequential excitation of Nd by the laser excitation is attributed to the 4I9/2 + 532 nm T 4G7/2 ground state absorption followed by the 4G7/2 + 532 nm T 2F5/2 and 2F5/2 + 532 nm T 4f25d excited state absorptions. The UV emissions due to 4f25d confi guration are parity allowed, having lifetime of 35 nanoseconds (ns) in contrast to UV emissions from 4f3 confi guration which are induced by two absorption steps and are parity forbidden showing longer lifetime of 8 microseconds (ms) and narrow lines. The polarization effects of the UV emissions were studied and their behaviors are dependent on the excited state confi guration involving or not involving the 5d orbital. The allowed UV emission positions were affected by the host variation more than the ones originated from the 4f3 confi guration as expected. The electronic energy of the 4f25d confi guration shifts to lower energy for increasing the crystal fi eld.
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Librantz, André Felipe Henriques, Luiz Vicente Gomes Tarelho, Laércio Gomes, and Izilda Márcia Ranieri. "Study of UV fluorescences induced from 4f3 T 4f25d multistep absorptions of Nd3+ions in YLiF4 and LuLiF4 crystals DOI: 10.5585/exacta.v4i1.671." Exacta 4, no. 1 (March 12, 2008): 179–83. http://dx.doi.org/10.5585/exactaep.v4i1.671.

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Nd3+ ultraviolet (UV) fl uorescence induced by multiphotonic laser excitations was studied in doped Nd:YLiF4 (YLF) and Nd:LuLiF4 (LLF) crystals by using the time resolved spectroscopy technique. The UV luminescences are due to transitions between the 4f25d and the 4f3 electronic confi gurations of Nd3+ ions. The 4f25d confi guration can be reached by direct pumping or by multiphotonic excitation, both processes give rise to the UV band emission with structure due to the strong phonon coupling expected for 5d orbital involvement in the transition. The multiphotonic excitation process is due to three photons (532 nanometers [nm]) sequential absorptions by metastable levels of the 4f3 confi guration split by crystalline local fi eld. The sequential excitation of Nd by the laser excitation is attributed to the 4I9/2 + 532 nm T 4G7/2 ground state absorption followed by the 4G7/2 + 532 nm T 2F5/2 and 2F5/2 + 532 nm T 4f25d excited state absorptions. The UV emissions due to 4f25d confi guration are parity allowed, having lifetime of 35 nanoseconds (ns) in contrast to UV emissions from 4f3 confi guration which are induced by two absorption steps and are parity forbidden showing longer lifetime of 8 microseconds (ms) and narrow lines. The polarization effects of the UV emissions were studied and their behaviors are dependent on the excited state confi guration involving or not involving the 5d orbital. The allowed UV emission positions were affected by the host variation more than the ones originated from the 4f3 confi guration as expected. The electronic energy of the 4f25d confi guration shifts to lower energy for increasing the crystal fi eld.
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Sweeney, Joyce A., and Sanford A. Asher. "Tryptophan UV resonance Raman excitation profiles." Journal of Physical Chemistry 94, no. 12 (June 1990): 4784–91. http://dx.doi.org/10.1021/j100375a009.

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Murgida, D. H., R. Erra-Balsells, and G. M. Bilmes. "New photocalorimetric references for UV excitation." Chemical Physics Letters 250, no. 2 (February 1996): 198–202. http://dx.doi.org/10.1016/0009-2614(95)01448-9.

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Gorelik, V. S. "Pulsed uv excitation of biological structures." Journal of Russian Laser Research 20, no. 2 (March 1999): 152–70. http://dx.doi.org/10.1007/bf02508691.

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Zheng, W. "Emission Lines in the Far-UV and Extreme-UV Region." International Astronomical Union Colloquium 159 (1997): 108–15. http://dx.doi.org/10.1017/s0252921100039750.

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AbstractRecent observations with HST and HUT have been made of the spectral region shortward of Lyα in AGN. Emission lines in this region, such as O VIλ1035 and Ne VIIIλ774, are mainly produced by collisional excitation. Their strengths and the lack of other significant emission lines of higher excitation energy indicate a temperature of ~ 6 × 104 K for the highly ionized gas in line-emitting clouds. Model calculations suggest that the strength of O VI and Ne vIII emission is correlated to the intensity of the high-energy photons above 100 eV. Therefore, these lines are useful diagnostics of the continuum shape in the soft X-ray range. The luminosity dependence of emission-line equivalent widths is more prominent for lines of higher ionization level, suggesting that the UV bump in AGN spectra may be weaker at higher luminosities.
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Plewa, Julian, and T. Juestel. "Synthesis and Optical Characterization of Pr3+ Doped UV Emitting Luminescent Ceramics." Materials Science Forum 636-637 (January 2010): 344–47. http://dx.doi.org/10.4028/www.scientific.net/msf.636-637.344.

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UV emitting luminescent materials are of strong interest for UV emitting fluorescent lamps driven by a Hg low-pressure or a by Xe excimer discharge. Pr3+ doped host lattices exhibit efficient UV emission upon deep UV excitation, if the site of the host lattice, where Pr3+ is located, is suitable for this purpose. This work deals with Pr3+ activated VUV ceramic luminophores, i.e. materials, which show efficient luminescence upon 160 nm excitation. As host lattices for the potentially UV emitting Pr3+ ion aluminates and silicates have been studied. All samples were prepared by conventional mix and fire synthesis techniques with metal oxides as starting materials. Firstly, powder samples were annealed between 1000 and 1700 °C and secondly, ceramic samples were repeatedly thermally treated at similar temperatures after pressing. It is demonstrated that translucent ceramics show mainly UV luminescence upon deep UV excitation, while excitation by a blue 450 nm LED results in green to red luminescence with a similar decay time as observed for single crystals.
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Wen, A. T., A. P. Hitchcock, N. H. Werstiuk, N. Nguyen, and W. J. Leigh. "Studies of electronic excited states of substituted norbornenes by UV absorption, electron energy loss, and HeI photoelectron spectroscopy." Canadian Journal of Chemistry 68, no. 11 (November 1, 1990): 1967–73. http://dx.doi.org/10.1139/v90-302.

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Valence and inner-shell (C1s) electronic excitation spectra of norbornene, 2-methylnorbornene, and 2-trifluoromethylnorbornene have been measured by electron energy loss spectroscopy. These data have been complemented with gas- and solution-phase UV absorption spectra in the 5–6.7 eV range, HeI UV photoelectron spectra, and AM1 semi-empirical calculations for the three compounds. The valence shell energy loss and UV absorption spectra show marked variations throughout the series of compounds, suggesting the presence of at least three low-lying electronic excited states. The spectral bands have been assigned as due to π,R(3s), π,π*, and π, R(3p) excitations on the basis of their term values and the differences between their intensities in the solution and gas phase absorption spectra. The valence shell spectra indicate that while the vertically-excited π,R(3s) state is substantially lower in energy than the (vertically-excited) π,π* state in norbornene and the 2-methyl derivative, they are nearly isoenergetic in 2-trifluoromethylnorbornene. This difference in excited state manifolds is reflected in profound differences between the solution phase photochemistry of norbornene and the 2-trifluoromethyl derivative.The carbon 1s spectra are even more sensitive to substituent than the valence shell energy loss spectra. An interpretation is proposed which reflects the spatially localized character of inner-shell excitation and a "group orbitals" picture of the unoccupied MO's as accessed by C1s excitation. Keywords: Rydberg, electron energy loss, UV absorption, UV photoelectron spectroscopy, alkene, gas-phase.
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Dissertations / Theses on the topic "Excitation uv"

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Zuchowicz-Arnaud, Iwona. "Polymérisation de l'acrylamide sous rayonnement réactivité de photoamorceurs solubles dans l'eau sous excitation UV /." Grenoble 2 : ANRT, 1987. http://catalogue.bnf.fr/ark:/12148/cb37610947q.

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Zuchowicz-Arnaud, Iwona. "Polymérisation de l'acrylamide sous rayonnement : réactivité de photoamorceurs solubles dans l'eau sous excitation UV." Mulhouse, 1987. http://www.theses.fr/1987MULH0059.

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Etude de la polymérisation radiochimique (rayon gamma) de l'acrylamide en présence de vinylcarbazole. Etude de la polymérisation photochimique (U. V. ) en présence de benzophénones solubles dans l'eau. Etude du mécanisme d'amorçage
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Katkar, Rajesh A. "The Effect Of Stationary UV Excitation On The Optical Behavior Of Electrochemically Self-Assembled Semiconductor Nanowires." VCU Scholars Compass, 2006. http://hdl.handle.net/10156/1983.

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Bouchama, Mohamed-Touffik. "Etude par spectroscopie UV de la capture électronique par des ions de charge 7 et 8 dans des cibles neutres." Lyon 1, 1988. http://www.theses.fr/1988LYO10106.

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Etude de l'echange de charge entre les ions o**(7+), ne**(7+), ar**(7+), kr**(7+), ar**(8+) kr**(8+) (8-80 kev) et hc ou h::(2), pour spectroscopie de photons. Analyse des spectres et identification de nouvelles raies pour la capture d'un electron par ar**(7+), ar**(8+), kr**(7+) et kr**(8+). Mesure des sections efficaces d'emission et deduction des sections efficaces des sous-niveaux nl et totales. Identification et mesure de la double capture radiative pour ar**(8+) et kr**(8+) avec hc, du processus de "transfert-ionisation pour ar**(8+) avec hc et h::(2), du processus de "transfert-excitation" pour ne**(7+) et ar**(7+) avec hc et h::(2). Pour n**(5+), proposition d'une methode nouvelle pour faire varier la fraction metastable du faisceau (1s2s **(3)s); mesure des sections efficaces de capture pour cet etat
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Reimers, Petra. "Studies of Light Emission from N-B doped 6H-SiC." Thesis, Linköping University, Semiconductor Materials, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-59739.

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The purpose of this thesis work was to find a way to measure basic light emission properties of nitrogen-and-boron-doped 6H-SiC, which are fabricated with a growth method developed at Linköping University. The research is in its initial phase and the light properties as well as optical measurement techniques are important. The aim is that the results of the measurements will provide feedback to the growth process what quality and doping levels that are required to get the maximum amount of light. The measurements were performed at the Laboratory of Lighting Technology, Technical University of Darmstadt, Germany.

Two measuring methods with different excitation sources were tested: a double monochromator and a setup using near UV-filters. While the double monochromator was able to project wavelengths in steps down to 0.5 nm with a high accuracy, the filters were only available in steps of 10 nm where the accuracy of the wavelength values varied. The double monochromator was chosen for the continuing measurements.

When using excitation light between 375-390 nm the emitted light was in the visible wavelength region. The light properties measured were the irradiance (measured in W/m2) and the peak wavelength were maximum luminescence occurred.

The result showed that sample 2-4 had a peak wavelength at approximately 580‑582 nm for the excitation wavelength 375 nm. For sample 5 the peak wavelength occurred at 582 nm at the excitation wavelength 390 nm. Sample 1, the unintentionally doped, did not show any measurable results as expected.

When irradiance of the excitation light was approx. 8 W/m2 the irradiance at the peak of luminescence for the samples varied between 15.03-29.35 mW/m2. The low values are believed to be the result of the emitted light scattering in all directions whereas the measurements are done in one direction and only from a small area of the sample.

The measurements has shown that it is possible to measure the light properties of the grown material even though the samples were not finalized (capsulated) LED’s. The results from the measurements are of interest for the continuing development of the material.

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Sebai, Sihem. "Synthèse et caractérisation de polyphosphates (Li/Na/K)(Y,La,Ln)(PO3)4 (Ln=Eu³⁺,Sm³⁺). Etude des propriétés de luminescence sous excitation VUV-UV." Thesis, Université Clermont Auvergne‎ (2017-2020), 2018. http://www.theses.fr/2018CLFAC067/document.

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Ce travail est consacré à l’élaboration de luminophores à base de polyphosphates d’ions alcalins et de terres rares, stœchiométriques ou activés en ions Eu3+ et Sm3+, émetteurs de fluorescence sous excitation VUV. Ces matériaux, de formulation LixNa1-xY1-yEuy(PO3)4 (x = 0 ; 0,25 ; 0,5 ; 0,75 ; 1 et 0,01 ≤ y ≤ 1), LixNa1-xLa(PO3)4 : 5 % Eu3+ (x = 0 ; 0,1 ; 0,2 ; 0,8 ; 0,9 ; 1), NaxK1-xLa(PO3)4 : 5 % Eu3+ (x = 0 ; 0,1 ; 0,2 ; 0,8 ; 0,9 ; 1) et LixNa1-xSm(PO3)4 (x = 0 ; 0,5 ; 1), ont été synthétisés par voie céramique et caractérisés principalement par diffraction des rayons X, spectroscopies infrarouge et Raman et analyses thermiques. Les analyses physico-chimiques et optiques, notamment grâce aux propriétés de sonde structurale de l’ion Eu3+, démontrent que la substitution croisée des ions alcalins Li+, Na+ et K+ n’est possible que dans une proportion relativement faible, ce qui lié aux différences de structures cristallographiques de ces matériaux. L’analyse des données spectroscopiques de l’ion Eu3+ selon la théorie de Judd et Ofelt confirme le lien étroit existant entre les propriétés optiques et structurales dans ces matériaux. Les spectres d’excitation sont caractérisés par une bande intense localisée dans le domaine VUV, respectivement due au mécanisme de transfert de charge Y3+-O2- et Eu3+-O2- dans les phases à l’yttrium dopées en ions Eu3+ et aux bandes 4f-5d pour les matériaux concentrés en ions Sm3+. Les matériaux concentrés en ions Eu3+ et Sm3+ sont émetteurs d’une intense fluorescence rouge et orange respectivement, démontrant l’absence d’extinction par concentration
This work is devoted to the development of phosphors based on polyphosphates of alkaline and rare earth ions, stoichiometric or activated with Eu3+ and Sm3+ ions, considered as light emitters under VUV excitation. These materials, with formula LixNa1-xY1-yEuy(PO3)4 (x = 0; 0.25; 0.5; 0.75; 1 and 0.01 ≤ y ≤ 1), LixNa1-xLa(PO3)4 : 5 % Eu3+ (x = 0; 0.1; 0.2; 0.8; 0.9; 1), NaxK1-xLa(PO3)4 : 5 % Eu3+ (x = 0; 0.1; 0.2; 0.8; 0.9; 1) and LixNa1-xSm(PO3)4 (x = 0; 0.5; 1), were synthesized in the solid state and characterized mainly by X-ray diffraction, infrared and Raman spectroscopies and thermal analysis. Physical-chemical and optical analyses, in particular using the Eu3+ ion as a structural probe, show that the cross-substitution of Li+, Na+ and K+ alkaline ions is possible only in a relatively small proportion, which is linked to the differences in crystallographic structures of these materials. The analysis of the Eu3+ ion spectroscopic data according to Judd and Ofelt theory confirms the close link between optical and structural properties in these materials. Excitation spectra are characterized by an intense band localized in the VUV domain, respectively due to the charge transfer mechanism Y3+-O2- and Eu3+-O2- for the Eu3+ doped yttrium materials and to the 4f-5d inter-configuration for the Sm3+ concentrated materials. Materials concentrated in Eu3+ and Sm3+ ions emit intense red and orange fluorescence respectively, demonstrating the absence of concentration quenching
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Faleiros, Marcelo Meira. "Espectroscopia ultrarrápida do polímero semicondutor luminescente MEH-PPV com excitação no ultravioleta." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/76/76132/tde-06122012-084909/.

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A indústria optoeletrônica passa por um período de transformação em que os materiais inorgânicos estão sendo substituídos pelos orgânicos, oligômeros e polímeros, na fabricação de alguns tipos de dispositivos. No entanto, fatores como baixa eficiência e tempo de vida impedem que os aparelhos com base nos polímeros entrem definitivamente no mercado. Para resolver estas questões, é necessário um conhecimento profundo da estrutura eletrônica desses materiais. Apesar do avanço científico, ainda existem pontos a esclarecer. Por exemplo, não existe um consenso sobre a natureza das excitações óticas primárias e dos processos não radiativos nos polímeros conjugados, principalmente com excitação no ultravioleta. Tais processos limitam a eficiência e podem influenciar nos processos fotoquímicos, determinando o tempo de vida de um dispositivo. Esses fenômenos ocorrem em alguns picossegundos e, portanto, a espectroscopia ultrarrápida é a técnica mais adequada para o seu estudo. Neste trabalho, foi implementado o aparato para espectroscopia de bombeio e prova em filmes finos de polímeros conjugados, no qual podem ser usados dois métodos de aquisição de dados, sensível à fase e pulso-a-pulso. O primeiro é o método padrão citado na literatura, no qual o feixe de excitação é modulado por um chopper e os sinais são medidos por amplificadores lock-in. No segundo, o condicionamento de sinais é feito por circuitos amplificadores e o processamento dos sinais é feito pulso-a-pulso. É um método que a princípio fornece melhor estatística, pois as flutuações do laser são normalizadas pulso-a-pulso, e não na média. Além disso, apresenta menor custo e torna o experimento de bombeio e prova mais simples, pois os únicos procedimentos críticos passam a ser a sobreposição dos feixes na amostra e a determinação do atraso zero entre bombeio e prova. Foi projetado e construído o circuito eletrônico de condicionamento de sinais e o software de aquisição foi desenvolvido em linguagem LabVIEW. Entretanto, o método pulso-a-pulso forneceu uma sensibilidade inadequada para o estudo de filmes poliméricos, (ΔT⁄T ~ 0,7%, limitada pelo ruído elétrico na amplificação dos pulsos detectados), em contraste com ΔT/T ~ 0,1% que foi alcançada pelo método sensível à fase. Desta maneira, foi usado o último método para o estudo da evolução do espectro e da dinâmica de emissão estimulada de um filme de MEH-PPV, com excitação no visível e no ultravioleta, permitindo o estudo da dinâmica de relaxação dos estados de mais alta energia. Os resultados no visível são compatíveis com os da literatura, o que demonstra a confiabilidade do aparato quanto à sensibilidade e resolução temporal e espectral. Os resultados com excitação no UV indicam que a transferência de energia de bandas mais energéticas para a banda π - π∗ (conversão interna) ocorre em aproximadamente 300 fs, confirmando as suposições da literatura quanto à relaxação energética ultrarrápida (regra de Kasha), além de sugerir a existência de bandas ainda mais energéticas do que as já conhecidas. Pretende-se futuramente determinar a eficiência de tal transferência energética, pois ela pode ser um fator limitante na eficiência de fotoluminescência em polímeros conjugados com excitação no ultravioleta.
The optoelectronics industry is currently undergoing a transition period in which inorganic materials are being replaced by organic materials, oligomers and polymers, in the fabrication of some types of devices. However, factors such as low efficiency and low lifetime prevent polymer based devices on entering the market definitely. The solution of these issues requires a thorough knowledge of the electronic structure of these materials, but despite of scientific advances, there are still points to be clarified. For example, there is no consensus on the nature of the primary optical excitations and non-radiative processes in conjugated polymers, specially with ultraviolet excitation. Such processes limit the efficiency and can influence the photochemical processes, determining the device lifetime. These phenomena occur on a femtosecond timescale and therefore, ultrafast spectroscopy is the most appropriate technique for their study. In this work, we implemented the apparatus for pump-probe ultrafast spectroscopy on thin films of conjugated polymers, which can be used with two methods of data acquisition, phase-sensitive and shot-by-shot. The first is the standard method reported in the literature in which the excitation beam is modulated by a chopper and the signals measured by lock-in amplifiers. In the second, the detector signal conditioning is done by conventional amplifier circuits, followed shot-to-shot signal processing. This method provides the best statistics, in principle, because the laser fluctuations are normalized for each pulse, instead of using the average. In addition, the apparatus has a lower cost and the experiment is simpler, having as critical procedures the alignment of the beams on the sample and the determination of zero delay, with all other procedures done via software. The electronic circuitry for signal conditioning was designed and built and data acquisition software that enables measurements with both methods was developed in the LabVIEW programming language. However, the shot-by-shot method provided an inadequate sensitivity for the study of polymeric films (ΔT⁄T ~0.7%, limited by electronic noise in the amplification of detector signals), compared with ΔT⁄T ~ 0.1%, which was achieved by the phase sensitive method, and was the goal at the beginning of the project. Thus, the latter method was used to study the evolution of the spectrum and dynamics of stimulated emission of a film of MEH-PPV, with excitation in the visible and UV, allowing the study of the dynamics of higher lying electronic states. The results in the visible are consistent with those reported in the literature, which demonstrates the performance of the apparatus with respect to sensitivity and time/spectral resolution. The results with UV excitation indicate that the energy transfer among the more energetic bands to the π - π* band (internal conversion) occurs in about 300 fs, confirming the assumptions of the literature on the ultrafast energy relaxation processes (Kashas rule), besides suggesting the existence of even more energetic bands than those currently known. As future work, we plan to measure the efficiency of this energy transfer process, since it may be the limiting step in determining the overall photoluminescence efficiency of conjugated polymers with ultraviolet excitation.
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Balandraud, Nathalie. "Etude du vieillissement simulé et in situ des bitumes routiers par IRTF et fluorescence UV en excitation-émission synchrones : détermination des relations structures chimiques - propriétés rhéologiques par analyse en composantes principales." Aix-Marseille 3, 1994. http://www.theses.fr/1994AIX30102.

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L'oxydation et le vieillissement de la matiere se traduisent le plus souvent par des evolutions structurales entrainant des modifications de comportement. Ceci est particulierement important en industrie, notamment pour les produits fossiles et derives. Ainsi, les phenomenes de vieillissement des bitumes routiers peuvent etre suivis par differentes methodes physiques et rheologiques. Cependant, pour mieux les apprehender, il est necessaire d'etudier l'evolution chimique des bitumes, en preservant au maximum leur integralite (approche globale). L'etude de leur oxydation apres vieillissement par test rtfot (en film mince, a chaud et sous air) ou en service (sur la route), a ete menee ponctuellement par prise de spectres irtf et de fluorescence uv en excitation-emission synchrones (ees). L'evolution des bitumes a ete simulee par oxydation en continu, dans une cellule irtf mise au point a cet effet. Resituer les phenomenes naturels et les tests industriels, en comparant les indices obtenus en discontinu avec ceux en continu, a permis de mieux apprehender les chemins reactionnels de ces matieres organiques complexes. Dans cet objectif, des indices de vieillissement ont ete determines a partir des spectres des bitumes et de leurs fractions asphalteniques et malteniques. En fluorescence uv ees, ces indices traduisent l'etat de condensation des especes aromatiques presentes. En irtf, les indices decrivent les structures chimiques et les groupements fonctionnels. Leur evolution est correlee a celle des indices de fluorescence. Cette etude a permis de mettre en evidence des differences de reactivite selon l'origine du bitume (sa composition, etc. ) et les conditions d'utilisation. L'analyse en composantes principales (acp) des bitumes, en fonction soit de leurs proprietes rheologiques et mecaniques, soit de leurs indices spectrometriques, est semblable. En consequence, l'influence du taux et de la nature de certaines structures chimiques du liant sur ses proprietes rheologiques est indeniable. Il est maintenant possible, connaissant la structure initiale des bitumes, d'estimer sinon de prevoir une partie de leurs comportements rheologiques et chimiques, durant les vieillissements thermiques et sur site, par une regression multilineaire de certains indices spectrometriques. L'interet des outils analytiques developpes (indices spectrometriques d'irtf et de fluorescence uv), simples a realiser, ne s'arrete pas a l'etude du vieillissement des bitumes. En effet, l'etude prospective realisee sur les bitumes polymeres a aussi demontre la pertinence de l'information apportee par cette methodologie analytique. Les fractions bitumineuses responsables du gonflement du polymere ont ainsi ete determinees. De meme, il est possible, par comparaison avec une banque de donnees spectrales, de prevoir les phenomenes de demixtion de polymere au sein du bitume et l'interet industriel de ces melanges
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Sarasanandarajah, Sivananthan. "Multiwavelength fluorescence studies of Bacillus bacterial spores." Thesis, University of Canterbury. Physics and Astronomy, 2007. http://hdl.handle.net/10092/3544.

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Fluorescence techniques are being considered for the detection and identification of bacterial spores. This thesis sets out to empirically characterize the detailed autofluorescence spectroscopic properties of spores and their target molecules. The multiwavelength fluorescence studies from a unique endogenous biomarker, dipicolinic acid (DPA) and its calcium salt (CaDPA) in bacterial spores are found to be useful for fluorescence characterization of spores. A systematic determination of the fluorescence profile of the major chemical components of Bacillus spores and the effect of UV irradiation on them has been performed in dry samples, wet paste and in aqueous solution. The thesis applies reliable tools for accurately describing complex nature of spectral profile from bacterial spores, and for interpreting and identifying their spectral properties. We show that multiwavelength fluorescence technique combined with Principal Component Analysis (PCA) clearly indicates identifiable grouping among dry and wet Bacillus spore species. Differences are also observed between dried, wet and redried spores, indicating the stark effect of hydration on fluorescence fingerprints. The study revealed that changes in fluorescence of spores due to hydration/drying were reversible and supports a recent model of a dynamic and dormant spore structure. The spectra were analysed with PCA, revealing several spectroscopically characteristic features enabling spore species separation. The identified spectral features could be attributed to specific spore chemical components by comparing the spore sample signals with spectra obtained from the target molecules. PCA indicated underlying spectral patterns strongly related to species and the derived components were correlated with the chemical composition of the spore samples. More importantly, we examined and compared the fluorescence of normal spores with a mutant of the same strain whose spores lack DPA. We discovered that the dramatic fluorescence enhancement of Bacillus spores can be caused by UV irradiation in the spectral region of this unique biomarker without any pre treatment. Differences between spectra of spores, spore strains and other biological samples are very marked and are due to the dominance of the dipicolinate features in the spore spectra. This could lead to a cheap, more sensitive, faster and reagentless bacterial spore detector.
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Mahiou, Rachid. "Transferts d'excitation optique et effets non lineaires dans des materiaux concentres en gadolinium." Clermont-Ferrand 2, 1987. http://www.theses.fr/1987CLF2E379.

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Fluorescence de nagdf::(4), k::(2)gdf::(5), gdcl::(3). Excitation selective dans l'ultraviolet (excitation a 1 photon) ou dans le rouge (excitation a 2 photons) d'une des composantes stark du multiplet **(6)p::(7/2) de gd**(3+). Le declin de la fluorescence entre 4,4k et la temperature ambiante permet de determiner le mode de diffusion de l'energie d'excitation. Effet de la densite d'excitation. Mise en evidence d'une fluorescence anti-stokes issue des niveaux **(6)g::(7/2), **(6)d::(3/2) et **(6)i::(7/2). Effet d'un champ magnetique
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Books on the topic "Excitation uv"

1

Collision processes and excitation of UV emission from planetary atmospheric gases: A handbook of cross sections. Australia: Gordon and Breach Science Publishers, 1998.

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Avakyan, SV, R. N. II'in, G. N. Ogurtsov, and V. M. Lavrov. Collision Processes and Excitation of UV Emission from Planetary Atmospheric Gases: A Handbook of Cross Sections. CRC, 1999.

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Book chapters on the topic "Excitation uv"

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Lindholm, E., and L. Åsbrink. "Excitation and UV spectroscopy." In Lecture Notes in Chemistry, 142–86. Berlin, Heidelberg: Springer Berlin Heidelberg, 1985. http://dx.doi.org/10.1007/978-3-642-45595-7_9.

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Richa, Rajeshwar P. Sinha, and Donat-P. Häder. "Physiological Aspects of UV-Excitation of DNA." In Photoinduced Phenomena in Nucleic Acids II, 203–48. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/128_2014_531.

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de Vries, Mattanjah S. "UV-Excitation from an Experimental Perspective: Frequency Resolved." In Topics in Current Chemistry, 33–56. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/128_2014_560.

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Nakashima, Shinichi, and Takeshi Mitani. "Characterization of SiC Crystals by Using Deep UV Excitation Raman Spectroscopy." In Silicon Carbide and Related Materials 2005, 333–38. Stafa: Trans Tech Publications Ltd., 2006. http://dx.doi.org/10.4028/0-87849-425-1.333.

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Nakano, K., Y. Harada, Y. Yamaoka, K. Miyawaki, N. Wakabayashi, K. Imaizumi, H. Takaoka, M. Nakaoka, and T. Takamatsu. "Analysis of Rat Colonic Mucosal Autofluorescence under Excitation with UV/Violet Light." In IFMBE Proceedings, 860–61. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-03879-2_240.

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Johansson, Sveneric, and Jørgen E. Hansen. "On the Excitation of the Fe II Multiplet UV 191 in Stellar Spectra." In Physics of Formation of FeII Lines Outside LTE, 235–41. Dordrecht: Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-009-4023-9_27.

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Belyaev, Yu E., A. V. Dem'yanenko, and A. A. Puretzky. "Gas-Phase Formation of Atoms, Clusters, and Ultrafine Particles in UV Laser Excitation of Metal Carbonyls." In ACS Symposium Series, 220–49. Washington, DC: American Chemical Society, 1993. http://dx.doi.org/10.1021/bk-1993-0530.ch017.

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Kim, HyunSook, and Henry Helvajian. "Threshold fluence UV laser excitation of W(100) and O2,H2,F/W(100): Photoejected ion KE distributions." In Laser Ablation Mechanisms and Applications, 87–95. New York, NY: Springer New York, 1991. http://dx.doi.org/10.1007/bfb0048357.

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Hoshino, Norihiro, Michio Tajima, Toshihiko Hayashi, Taro Nishiguchi, Hiroyuki Kinoshita, and Hiromu Shiomi. "Nondestructive Analysis of Stacking Faults in 4H-SiC Bulk Wafers by Room-Temperature Photoluminescence Mapping under Deep UV Excitation." In Materials Science Forum, 275–78. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-442-1.275.

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Neto, M. A. C. "UV Emission in Natural Diamonds." In Spectroscopy and Dynamics of Collective Excitations in Solids, 639. Boston, MA: Springer US, 1997. http://dx.doi.org/10.1007/978-1-4615-5835-4_62.

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Conference papers on the topic "Excitation uv"

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Eversole, Jay D., C. S. Scotto, Mel Spence, and Anthony J. Campillo. "Continuous bioaerosol monitoring using UV excitation fluorescence." In 19th Congress of the International Commission for Optics: Optics for the Quality of Life, edited by Giancarlo C. Righini and Anna Consortini. SPIE, 2003. http://dx.doi.org/10.1117/12.525515.

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Fereidouni, Farzad, Zachary Harmany, Stavros Demos, and Richard Levenson. "MUSE: Microscopy via UV excitation for rapid histology." In 2016 IEEE Photonics Conference (IPC). IEEE, 2016. http://dx.doi.org/10.1109/ipcon.2016.7831018.

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Sivaprakasam, Vasanthi, Alan L. Huston, Cathy S. Scotto, and Jay D. Eversole. "Multiple UV wavelength excitation and fluorescence of bioaerosols." In Optics East, edited by Arthur J. Sedlacek III, Steven D. Christesen, Tuan Vo-Dinh, and Roger J. Combs. SPIE, 2004. http://dx.doi.org/10.1117/12.571296.

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Aschenbrucker, J., U. Steegmuller, and N. P. Ernsting. "Picosecond Infrared Spectroscopy of I-Naphtyl Isocyanate Following UV Excitation." In EQEC'96. 1996 European Quantum Electronic Conference. IEEE, 1996. http://dx.doi.org/10.1109/eqec.1996.561914.

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Ashikhmin, Michael V., Axel Mellinger, and C. B. Moore. "Photodissociation of singlet ketene by two-step IR+UV excitation." In Optoelectronics and High-Power Lasers & Applications, edited by John W. Hepburn, Robert E. Continetti, and Mark A. Johnson. SPIE, 1998. http://dx.doi.org/10.1117/12.308388.

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Kaczmarek, Slawomir M., Miroslaw Kwasny, Michal Malinowski, and Zbigniew Moroz. "Excitation emission spectra of laser materials for UV-VIS range." In Laser Technology V, edited by Wieslaw L. Wolinski and Michal Malinowski. SPIE, 1997. http://dx.doi.org/10.1117/12.280525.

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Tiihonen, Mikael, Valdas Pasiskevicius, Fredrik Laurell, and Mikael Lindgren. "A novel UV-laser source for fluorescence excitation of proteins." In European Symposium on Optics and Photonics for Defence and Security, edited by John C. Carrano and Arturas Zukauskas. SPIE, 2004. http://dx.doi.org/10.1117/12.568436.

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Levenson, Richard, Farzad Fereidouni, Zachary Harmany, and Stavros Demos. "Slide-Free (But Not Necessarily Stain-Free) Microscopy via UV Excitation." In CLEO: Science and Innovations. Washington, D.C.: OSA, 2016. http://dx.doi.org/10.1364/cleo_si.2016.sm1o.1.

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Ewart, M., M. Zgonik, and P. Gunter. "Nanosecond Optical Response to Pulsed UV Excitation in KNbO/sub 3/." In Proceedings of European Meeting on Lasers and Electro-Optics. IEEE, 1996. http://dx.doi.org/10.1109/cleoe.1996.562149.

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Wilson, Geoffrey A., and Richard K. DeFreez. "Autofluorescence detection using UV diode laser simultaneous excitation of multiple wavelengths." In AeroSense 2003, edited by Edward M. Carapezza. SPIE, 2003. http://dx.doi.org/10.1117/12.500865.

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Reports on the topic "Excitation uv"

1

Dr. Gerlad Lapeyre. Investigation of the Quantrum Structure of Surfaces with Far UV Excitation Spectrosscopies. Office of Scientific and Technical Information (OSTI), October 2008. http://dx.doi.org/10.2172/939625.

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