Academic literature on the topic 'Fluorescence coefficients'
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Journal articles on the topic "Fluorescence coefficients"
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Enderlein, Jörg. "Fluorescence correlation spectroscopy (IUPAC Technical Report)." Pure and Applied Chemistry 85, no. 5 (April 2, 2013): 999–1016. http://dx.doi.org/10.1351/pac-rep-11-11-17.
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We present an overview on the applicability of fluorescence correlation spectroscopy (FCS) for the accurate determination of translational diffusion coefficients and thus, via the Stokes–Einstein relation, of molecular size. We consider several of the most common sources of optical aberrations and their impact on the outcome of conventional FCS measurements. We describe also a new variant of FCS, dual-focus FCS, which is robust against most of the considered aberrations, and we report reference values of diffusion coefficients for several fluorescent dyes across the visible spectrum.
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Sarmento, M. J., S. N. Pinto, A. Coutinho, M. Prieto, and F. Fernandes. "Accurate quantification of inter-domain partition coefficients in GUVs exhibiting lipid phase coexistence." RSC Advances 6, no. 71 (2016): 66641–49. http://dx.doi.org/10.1039/c6ra13170k.
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Giant unilamellar vesicles (GUVs) with phase coexistence allow for the recovery of inter-domain partition coefficients (Kp) of fluorescent molecules through comparison of fluorescence intensities in each phase.
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Antony, Sumy, Jonathan C. Morris, Toby D. M. Bell, Tracey Brown, Leone Spiccia, and Hugh H. Harris. "The H.G. Smith Award Article: Fluorescent Analogues of NAMI-A: Synthesis, Characterisation, Fluorescent Properties, and Preliminary Biological Studies in Human Lung Cancer Cells." Australian Journal of Chemistry 67, no. 12 (2014): 1711. http://dx.doi.org/10.1071/ch14205.
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Two new fluorescent ruthenium(iii) complexes, namely 7-azaindolium trans-tetrachlorido(7-azaindole)(dimethylsulfoxide)ruthen(iii)ate (F1) and N-[histaminedihydrolium]-1,8-naphthalenecarboximidic trans-tetracholoro(dimethylsulfoxide)(N-[histaminedihydro]-1,8-naphthalenecarboximide)ruthen(iii)ate (F2) and their respective tetramethylammonium analogues (F3 and F4) are reported herein. The compounds were characterised by elemental analysis, mass spectrometry, UV-vis spectrophotometry, and fluorescence spectroscopy. Molar extinction coefficients (ϵmax) and fluorescence emission spectra were compared to evaluate the electronic properties of the synthesised fluorescent analogues, and hence their value as intracellular fluorescence probes. F3 and F4 were synthesised and characterised in order to eliminate fluorescence arising from the counter-cations in F1 and F2 and thus to obtain a fluorescence quantum yield that reflects only a contribution from the metal complex anion. Half-inhibitory concentrations (IC50) were determined for A549 cells exposed to the Ru complexes for 24 h: F3 (203 ± 26 μM) and F4 (185 ± 20 μM).
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Waharte, François, Karine Steenkeste, Romain Briandet, and Marie-Pierre Fontaine-Aupart. "Diffusion Measurements inside Biofilms by Image-Based Fluorescence Recovery after Photobleaching (FRAP) Analysis with a Commercial Confocal Laser Scanning Microscope." Applied and Environmental Microbiology 76, no. 17 (July 16, 2010): 5860–69. http://dx.doi.org/10.1128/aem.00754-10.
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ABSTRACT Research about the reactional and structural dynamics of biofilms at the molecular level has made great strides, owing to efficient fluorescence imaging methods in terms of spatial resolution and fast acquisition time but also to noninvasive conditions of observation consistent with in situ biofilm studies. In addition to conventional fluorescence intensity imaging, the fluorescence recovery after photobleaching (FRAP) module can now be routinely implemented on commercial confocal laser scanning microscopes (CLSMs). This method allows measuring of local diffusion coefficients in biofilms and could become an alternative to fluorescence correlation spectroscopy (FCS). We present here an image-based FRAP protocol to improve the accuracy of FRAP measurements inside “live” biofilms and the corresponding analysis. An original kymogram representation allows control of the absence of perturbing bacterial movement during image acquisition. FRAP data analysis takes into account molecular diffusion during the bleach phase and uses the image information to extract molecular diffusion coefficients. The fluorescence spatial intensity profile analysis used here for the first time with biofilms is supported both by our own mathematical model and by a previously published one. This approach was validated to FRAP experiments on fluorescent-dextran diffusion inside Lactoccocus lactis and Stenotrophomonas maltophilia biofilms, and the results were compared to previously published FCS measurements.
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Buse, Ben, and Stuart Kearns. "Quantification of Olivine Using Fe Lα in Electron Probe Microanalysis (EPMA)." Microscopy and Microanalysis 24, no. 1 (February 2018): 1–7. http://dx.doi.org/10.1017/s1431927618000041.
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AbstractQuantification of first series transition metal Lα X-rays is hampered by absorption and in some cases transition probabilities (fluorescence yields) varying with chemical bonding. Compound mass absorption coefficients for Fe Lα were measured in the olivine solid solution series [Forsterite (Mg2SiO4) to Fayalite (Fe2SiO4)] and the mass absorption coefficients for Fe Lα absorbed by Fe were calculated. The mass absorption coefficients vary systematically between Fo83 and Fo0. Using the measured mass absorption coefficients for both standard and unknown and by correcting for a systematic discrepancy, consistent with varying partial fluorescence yields, a good agreement between calculated k-ratios and measured k-ratios is achieved. The systematic variations allow quantification of unknown k-ratios. The described method of quantification requires modification of matrix correction routines to allow standards and unknowns to have different mass absorption coefficients, and to incorporate solid solution mass absorption coefficients and partial fluorescence yield corrections derived from regression of experimental data.
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Chandrasekaran, Vijayanand, Bhim Kafle, Aneesh Prabhakaran, Oded Heber, Michael Rappaport, Hilel Rubinstein, Dirk Schwalm, Yoni Toker, and Daniel Zajfman. "Determination of Absolute Recurrent Fluorescence Rate Coefficients for C6–." Journal of Physical Chemistry Letters 5, no. 23 (November 14, 2014): 4078–82. http://dx.doi.org/10.1021/jz502100z.
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Unonius, L., and P. Suortti. "Mass attenuation coefficients of the elements Ti, V, Fe, Co, Ni, Cu and Zn for the K emission lines between 4.51 and 10.98 keV." Journal of Applied Crystallography 22, no. 1 (February 1, 1989): 46–52. http://dx.doi.org/10.1107/s0021889888010817.
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Mass attenuation coefficients of seven elements between atomic numbers 22 and 30 were measured at 20 X-ray energies between 4.5 and 11 keV. These energies correspond to fluorescence radiation excited by monochromatic Mo Kα radiation. The measurements were made on thin metal foils, which were spread flat and perpendicular to the beam scattered from the fluorescent sample. In this arrangement, the measured attenuation includes photoelectric absorption plus average elastic and inelastic scattering. The mass per unit area of a foil was determined by weighing and the impurity concentration by fluorescence analysis. The spectral lines corresponding to the components of the fluorescent radiation and those of the secondary radiation were resolved by the so-called singular value decomposition (SVD). The probable errors of the attenuation coefficients were typically 1%. The general agreement with previous experimental and theoretical values is good, but at low energies and at energies just above the absorption edges the present values are about 5% larger than theoretical values based on relativistic HFS (Hartree–Fock–Slater) calculations.
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Rousseau, Richard M. "Why The Fundamental Algorithm is So Fundamental." Advances in X-ray Analysis 37 (1993): 639–46. http://dx.doi.org/10.1154/s0376030800016190.
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In X-ray fluorescence (XRF) analysis, one of the major problems is the correction for matrix effects (absorption and enhancement). One of the solutions proposed was the use of influence coefficients, which are numerical coefficients that correct for the effect of each matrix element on the analyte. For many years, these coefficients were considered as an empirical approach having little connection with X-ray fluorescence theory. They were considered useful only when no other alternative was available to solve the problem of matrix effect.
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Zhang, Zeshi, Elena Nadezhina, and Kevin J. Wilkinson. "Quantifying Diffusion in a Biofilm ofStreptococcus mutans." Antimicrobial Agents and Chemotherapy 55, no. 3 (December 28, 2010): 1075–81. http://dx.doi.org/10.1128/aac.01329-10.
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ABSTRACTIn biofilms, diffusion may limit the chemical activity of nutrients, toxic compounds, and medicines. This study provides direct, noninvasive insight into the factors that will most effectively limit the transport of antibiotics and biocides in biofilms. Self-diffusion coefficients have been determined for a number of fluorescent probes in biofilms ofStreptococcus mutansusing fluorescence correlation spectroscopy. The effects of probe size and charge and the roles of biofilm pH, ionic strength, and heterogeneity were studied systematically. The relative diffusion coefficients (Din the biofilm divided by that in water) decreased with increasing probe size (3,000-molecular-weight [3K], 10K, 40K, 70K, and 2,000K dextrans). Studies using variably charged substrates (tetramethylrhodamine, Oregon Green, rhodamine B, and rhodamine 6G) showed that the self-diffusion coefficients decreased with an increasing negative charge of the fluorescent probes. No significant effect was observed for changes to the ionic strength (10−4to 10−1M) or pH (4 to 9) of the biofilm. Biofilm heterogeneity was responsible for variations of ca. one order of magnitude in the diffusion coefficients.
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Petrášek, Zdeněk, and Petra Schwille. "Precise Measurement of Diffusion Coefficients using Scanning Fluorescence Correlation Spectroscopy." Biophysical Journal 94, no. 4 (February 2008): 1437–48. http://dx.doi.org/10.1529/biophysj.107.108811.
Full textDissertations / Theses on the topic "Fluorescence coefficients"
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Ali-Romson, Farida. "Détermination de coefficients de diffusion par diverses techniques de spectroscopie de fluorescence." Vandoeuvre-les-Nancy, INPL, 1991. http://www.theses.fr/1991INPLA001.
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Cassan, Ludovic. "Fluorescence induite par rayonnement solaire concentré : application à la mesure de températures et à la détermination de coefficients de desexcitation collisionnelle de la molécule YO." Perpignan, 2005. http://www.theses.fr/2005PERP0645.
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La connaissance de la température de la phase gaz au voisinage du front chaud existant lors de l'utilisation de fours solaires à concentration peut s'avérer importante pour la maîtrise des procédés faisant appel à ces technologies. Pour accéder à ce paramètre nous avons utilisé un phénomène inhérent à ces installations: la fluorescence induite par absorption d'une fraction du rayonnement solaire incident servant à chauffer l'échantillon. Cette thèse présente l'étude de la fluorescence de la molécule diatomique YO générée lors de la fusion d'oxyde d'yttrium au foyer d'un four de 1,5 kW dans des atmosphères d'argon ou d'hélium. La température désirée est obtenue en comparant les spectres mesurés par spectroscopie optique des systèmes A2P1/2-X2S+, A2P3/2- X2S+, B2S+- X2S+ de la molécule YO et ceux calculés de ces mêmes bandes. On mesurera aussi ces temperatures par une méthode d'absorption dont le faisceau de référence est obtenu par prélèvement de rayonnement sur le faisceau direct de l'héliostat associé au four solaire. Le modèle de calcul des spectres est un modèle à trois températures (électronique, vibration, rotation). Les résultats obtenus se comparent favorablement à un modèle fluide (Fluent) mais montrent, à basse pression et au voisinage du front chaud, des déséquilibres importants entre ces différentes températures. On explique ces déséquilibres, dans cette situation, par l'existence d'une couche de Knudsen au voisinage de l'échantillonThe knowledge of the gas phase temperature in the vicinity of the hot front in solar processes involving high concentration solar furnaces is an important parameter for the control of these processes. In order to measure this parameter we used a phenomenon inherent in these facilities : fluorescence induced by absorption of a fraction of the incident radiation used to heat the sample. This work concerns the fluorescence of the YO diatomic molecule issuing from an Y2O3 sample melted in argon or helium at the focus of a 1. 5 kW solar furnace. Temperatures are deduced from the comparison between measured and computed spectra of YO bands (A2P1/2-X2S+, A2P3/2-X2S+, B2S+-X2S+). These temperatures are also deduced from spectra obtained with an absorption method, the reference beam being withdrawn from the direct beam from the heliostat associated to the concentrator. The model used to calculate the band spectra is a three temperatures model (electronic, vibrational, rotational). The results are consistent with the calculation from a computational fluid dynamic software (Fluent). However the measurements show large discrepancies at low pressure and near the hot front. These discrepancies can be accounted for by a Knudsen layer in the vicinity of the hot front
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Krist, Tomáš. "Sekvenční frakcionace organické hmoty huminové kyseliny izolované z Leonarditu." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-445142.
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The aim of the diploma thesis was to optimize the sequential fractionation method of organic matter to be used for physico-chemical characterization of extracted fractions. Humic acid isolated from oxidized brown coal of Leonardite was used as a source matrix of organic matter. An eluotropic series was assembled and sequential fractionation was performed by extraction on a Soxhlet apparatus. The original humic acid and fractions were characterized by elemental analysis (EA) and thermogravimetric analysis (TGA), followed by Fourier transform infrared spectrometry (FTIR), molecular absorption spectrometry (UV/VIS), fluorescence spectrometry and potentiometric titration. Atomic ratios were determined from the results of the elemental analysis. From the measured UV/Vis and fluorescence excitation and emission spectra, the absorption coefficients, resp. fluorescence coefficients. Used fractionation method proved to be a suitable method for studying HA structure. A total of 62 wt. % of initial materiál was extracted, indiivdual fraction amounted from 0.36–30.92 wt. %. From the results of the structural analysis, it is clear that with increasing polarity of the organic solvent, fractions with long aliphatic chains were first isolated and their aromaticity graddualy increased. Non-polar organic solvents were suitable for the extraction of lipid-like coumpounds, while the most polar organic fractions were rich in polar groups and their structual parameters were close to the original humic acid. The fraction extracted with acetonitrile was the most unique fraction. This fraction was rich on nitrogen and amine groups and was similar to protein-like structures. In the last two fractions, extracted with alcohols, a significant bathochromic shift typical of fluorophore type V was observed. Among other things, they were also characterized by a higher content of plant carbohydrate residues.
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Zhang, Zhengyu. "Laser-Induced Nucleation in a Coaxial Microfluidic Mixer." Thesis, Université Paris-Saclay (ComUE), 2019. http://www.theses.fr/2019SACLN023.
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La cristallisation est une des opérations élémentaires du génie chimique. Les matières produites sont extraites par cristallisation et purifiées par recristallisation. Mais la nucléation du cristal reste un mystère et la théorie classique de la nucléation est battue en brèche par de nombreuses données expérimentales. Nous avons construit un dispositif microfluidique de précipitation par mélange de solvants pour produire de manière continue et observer la formation d’un grand nombre de cristaux. La molécule étudiée est le DBDCS dont les cristaux sont fluorescents mais pas la molécule. Le germe sera ainsi le premier objet lumineux du mélange.Nous avons calculé la thermodynamique du mélange ternaire DBDCS/1,4-dioxane(diox)/eau à partir de ce qui est connu pour le mélange diox/eau et de la courbe de solubilité du DBDCS dans diox/eau, dans le cadre d’un modèle de solution régulière. Il permet de calculer les conditions de la décomposition spinodale ([DBDCS]= 59 fois la saturation) du mélange ternaire en une phase liquide hypothétique de DBDCS pratiquement pur dans un mélange diox/eau.Nous observons cette phase dans une expérience de précipitation après 6ms de mélange. La mesure du volume de cette phase liquide confirme qu’elle est pratiquement pure. L’apparition de cette phase liquide nécessite une forte sursaturation. Celle-ci fait suite à la diffusion de l’eau qui repousse et concentre le DBDCS au centre du dispositif. L’étude du temps mis à atteindre la concentration critique en fonction de la concentration initiale en DBDCS dans le flux central permet d’obtenir une valeur de 50 à 70 fois la saturation pour la concentration critique d’apparition de la phase liquide DBDCS. Le produit de cette décomposition spinodale est un nuage de gouttelettes sub-micrométriques. Mais le gradient de potentiel chimique peut, dans certaines conditions, regrouper ces nano-gouttes en un chapelet de gouttes micrométriques de même taille.Lorsque l’anti-solvant n’est pas de l’eau pure, mais un mélange diox/eau, la barrière de potentiel ne l’emporte pas sur l’entropie de la diffusion, ce que montre la répartition de la fluorescence résiduelle des molécules (rendement<10-4). Sur des temps de l’ordre de 5s, on observe la formation et la croissance de cristaux dans un mélange localement homogène. La simulation numérique indique que dans ces conditions la sursaturation relative ne dépasse pas 3,5. L’imagerie rapide et la fluorescence permettent d’observer les cristaux un par un. Trois polymorphes différents sont identifiables par leur durée de vie : les phases vertes et bleues déjà observées et une phase de courte durée de vie. Ces cristaux présentent une vitesse de croissance moyenne proportionnelle à la concentration locale.En focalisant un laser sur les nuages de nano-gouttes, on observe un effet de pince optique capable de rassembler ces gouttes. En focalisant ce laser dans la zone de super-saturation maximale dans des conditions de nucléation spontanée, on observe une multiplication du nombre de cristaux formés d’un facteur cinq. Nous sommes en présence d’une nucléation induite par laser. Ces cristaux présentent la même vitesse de croissance, la même distribution en nombre des polymorphes, que les cristaux obtenus spontanément. Cette nucléation induite par laser est donc très douce et induit un changement minimal du mécanisme de la nucléation. Un effet de pince optique qui concentre localement les précurseurs du germe et augment transitoirement la sursaturation pourrait avoir cet effet.Cette nucléation induite par laser permet de localiser la nucléation. Au point focal du laser NPLIN, nous observons l’accumulation d’une phase de durée de vie de fluorescence courte, donc peut être désordonnée. Elle disparaît après le passage dans le laser pendant qu’une phase de grande durée de vie (la phase verte) croit lentement. Ce serait une observation directe d’une nucléation en deux étapesCrystallization is one of the elementary operations of chemical engineering. The materials produced are extracted by crystallization and purified by recrystallization. But the nucleation of the crystal remains a mystery and the classical theory of nucleation is undermined by numerous experimental data. We have chosen to build a microfluidic precipitation device by mixing solvents to produce and continuously observe the birth of a large number of crystals. The molecule chosen for the study is DBDCS, with fluorescent crystals but not the molecule. The germ will thus be the first luminous object in the mixture.We calculated the thermodynamics of the ternary mixture DBDCS/diox/water from what is known for the mixture diox/water and the solubility curve of DBDCS in diox/water, as part of a regular solution model. We calculate the conditions of the spinodal decomposition ([DBDCS]= 59 times the saturation) of the ternary mixture into a hypothetical liquid phase of DBDCS practically pure in a diox/water mixture.However, this hypothetical phase we observe it as the main initial product of this precipitation experience. The measurement of the volume produced by this liquid phase confirms that it is practically pure. The appearance of this liquid phase requires a strong oversaturation following the diffusion of water. The study of the solubility of DBDCS in diox/water shows that the chemical potential of DBDCS in water is 17 RT higher than its value in diox. The diffusion of water in diox induces the formation of an energy barrier that repels and concentrates DBDCS to the center of the device. The study of the time taken to reach the critical concentration as a function of the initial concentration of DBDCS in the central flow provides a value 50 to 70 times the saturation for the critical concentration of occurrence of the DBDCS liquid phase. This confirms that we observe a spinodal decomposition. The product of this spinodal decomposition is a cloud of sub-micrometric droplets. But the chemical potential gradient can, under certain conditions, group these nanodrops into a string of micrometric drops of the same size.When the anti-solvent is not pure water, but a diox/water mixture, the potential barrier does not outweigh the entropy of the diffusion. This is shown by the distribution of the fluorescence of the molecules (yield<10-4). Over times of the order of 5s, the formation and growth of crystals is observed. The numerical simulation indicates that under the conditions the relative oversaturation does not exceed 3.5. Rapid imaging and fluorescence allow the crystals to be observed one by one. Three different polymorphs are identifiable by their lifetime : the green and blue phases already observed and a short-lived phase. The growth rates are widely dispersed, making it difficult to locate and observe spontaneous nucleation.By focusing a laser on the clouds of nanodrops, we observe an optical tweezer effect capable of collecting these drops. By focusing this laser in the zone of maximum super-saturation under spontaneous nucleation conditions, we observe a multiplication of the number of crystals formed by a factor of five. We are in the presence of laser-induced nucleation. These crystals have the same growth rate, the same distribution in number of polymorphs, as the spontaneously obtained crystals. This laser-induced nucleation is therefore very soft and induces a minimal change in the nucleation mechanism. An optical tweezer effect that locally concentrates the precursors of the germ and increases the over-saturation could have this effect.This laser-induced nucleation makes it possible to locate the nucleation. At the focal point of the NPLIN laser, we observe the accumulation of a phase with a short fluorescence lifetime, so it can be disordered, which disappears after the passage in the laser while the green phase grows slowly. This would be a direct observation of a two-step nucleation
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Yang, Xin. "Study of the hydrogen-tungsten interaction for fusion : measurement of the atomic reflection coefficient by laser spectroscopy." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0232.
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Les interactions plasma surface (PSI) sont considérées comme l'un des défis scientifiques majeurs de la fusion nucléaire magnétique contrôlée. L'interaction entre les isotopes d'hydrogène et les matériaux de l’enceinte à plasma tels que le tungstène revêt une importance particulière. Le coefficient de perte en surface des isotopes atomiques (γ) est un point clé dans les études PSI. Il peut donner des informations sur le recyclage de l'hydrogène atomique à la paroi et constitue ainsi un paramètre clé dans les modélisations des interactions plasma surface. Le but de ce projet est de déterminer les coefficients de perte de surface de l'hydrogène atomique et du deutérium sur échantillons de tungstène (W) et de nitrure de tungstène (WN) en utilisant une technique de fluorescence induite par plasma (PIF) et une technique de fluorescence induite par laser à deux photons (TALIF). Ce projet s'effectue dans le réacteur CAMITER qui est un réacteur plasma radiofréquence à basse pression au laboratoire PIIM de l'Université Aix-MarseillePlasma surface interaction (PSI) is considered to be one of the key scientific challenges in nuclear fusion. The interaction between hydrogen isotopes and plasma-facing materials such as tungsten is of particular importance. The atomic hydrogen isotope surface loss coefficient (γ) is a key point in PSI studies. It can give information on hydrogen isotope inventory and is an important input for modeling and theoretical work. The aim of this project is to determine atomic hydrogen and deuterium surface loss coefficients on tungsten (W) sample by using two-photon-absorption laser induced fluorescence (TALIF) and pulsed induced fluorescence (PIF) technique. This project is carried out in CAMITER reactor which is a low-pressure radio-frequency ICP reactor at PIIM laboratory in Aix-Marseille University
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Ezhilan, Madhumitha. "Commissioning a Commercial Laser Induced Fluorescence System for Characterization of Static Mixer Performance." University of Dayton / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1499793560290147.
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Enev, Vojtěch. "Spektrometrické metody pro výzkum huminových látek." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2016. http://www.nusl.cz/ntk/nusl-234656.
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The main aim of doctoral thesis is the study on physicochemical properties of humic substances (HS) by modern instrumental techniques. The subject of the study were HS isolated from South Moravian lignite, South Bohemian peat, forest soil Humic Podzol and finally extract from brown sea algae Ascophyllum nodosum. With respect on determination of structure and reactivity of these unique “biocolloids”, standard samples (Leonardite HA, Elliott Soil HS and Pahokee Peat HS) were also studied. These samples were obtained from International Humic Substances Society (IHSS). All mentioned substances were characterized by elemental analysis (EA), molecular absorption spectroscopy in ultraviolet and visible region (UV/Vis), infrared spectroscopy with Fourier transformation (FTIR), nuclear magnetic resonance spectroscopy of carbon isotope 13C (LS 13C NMR), steady-state and time resolved fluorescence spectroscopy. Obtained fluorescence, UV/Vis and 13C NMR spectra were used for calculation of fluorescence and absorption indexes, values of specific absorbance and structural parameters respectively, which were used for fundamental characterization of these “biocolloidal” compounds. Infrared spectroscopy with Fourier transformation was utilized for the identification of functional groups and structural units of HS. Evaluation of infrared spectra is quiet complicated by overlapping of absorption bands especially in fingerprint region. This problem was overcome by Fourier self-deconvolution (FSD). Steady-state fluorescence spectroscopy was used for deeper characterization of HS with respect to origin, structural units, amount of substituents with electron-donor and electron-acceptor effects, content of reactive functional groups, “molecular” heterogeneity, the degree of humification, etc. Parameters of complexation of samples Elliott Soil with heavy metal ions (Cu2+, Pb2+ and Hg2+) were obtained by using modified Stern-Volmer equation. These ions were chosen purposefully, because the interaction of HS with these ions is one of the fundamental criteria for the assessment of the reactivity of HS. Key part of the whole doctoral thesis is time-resolved fluorescence spectroscopy. It is able to determine the origin of emission of HS by method Time-Resolved Area Normalized Emission Spectra (TRANES). The viscosity of micro medium about excited fluorophores of HS was determined by Time-Resolved Emission Spectra (TRES).
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Pandelieva, Antonia. "Increasing the Quantum Yield of Red Fluorescent Proteins Using Rational Design." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34272.
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Monomeric red fluorescent proteins (RFPs) are used extensively for applications in molecular biology research, and are especially suited for whole body imaging applications due to their longer excitation and emission wavelengths, which are less damaging and penetrate deeper into animal tissue. However, these proteins suffer from reduced brightness compared to other fluorescent proteins, and require further engineering, which is often achieved through random methods, incurring large time and resource costs. Here we propose a rational design approach to improve the quantum yield of RFPs by reducing conformational variability of the chromophore. We engineered mRojoA, a mutant containing a π-stack involving Tyr197 and the chromophore phenolate, to include the P63F/H/Y mutations on its other side, by simultaneously mutating neighbouring positions 16, 143, and 163. The brightest mutants that we found in each library, mRojo-VYGV, mRojo-VFAV, and mRojo-VHSV, exhibited 1.8- to 2.4-fold increases in brightness, and quantum yield increases of up to 2.1-fold. In all three mutants, the increases in brightness were predominantly due to improvements in the quantum yield and not the extinction coefficient. Solving the crystal structures of two of these mutants along with a dim variant allowed us to strongly infer a link between rigidity of the chromophore and increased quantum yield. In addition, back-mutating position 63 in the highest quantum yield mutant, mRojo-VYGV, reversed the improvement in quantum yield, indicating that Y63 was the primary residue responsible for the improved brightness of the protein. Unfortunately, the mCherry-VYGV mutant did not achieve a similar increase in quantum yield or brightness. This is likely due to the lack of a second bulky aromatic residue at position 197, which is present in mRojoA. Nevertheless, this rational approach could be applied to some other RFPs whose chromophores exhibit increased conformational variability in order to further improve their brightness.
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Sauzède, Raphaëlle. "Etude et paramétrisation de la distribution verticale de la biomasse phytoplanctonique dans l'ocean global." Thesis, Paris 6, 2015. http://www.theses.fr/2015PA066625/document.
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Les travaux présentés dans cette thèse concernent la paramétrisation de la distribution verticale de la biomasse et de la structure des communautés phytoplanctoniques dans l’océan global. Nous avons d’abord développé une méthode neuronale de calibration de la fluorescence en concentration en chlorophylle a ([Chl]) associée à la biomasse phytoplanctonique totale et à trois classes de taille de phytoplancton. Cette méthode, FLAVOR, a été entrainée et validée à l’aide une base de données de ~900 profils de fluorescence et de pigments mesurés pat HPLC. Une base de données globale de ~49000 profils de fluorescence a ensuite été assemblée et calibrée en termes de biomasse chlorophyllienne et composition du phytoplancton. Ce travail représente une première étape vers une vision tridimensionnelle de la biomasse phytoplanctonique. Nous avons ensuite développé deux réseaux de neurones (SOCA) pour estimer la distribution verticale de deux paramètres bio-optiques, [Chl] et le coefficient de rétrodiffusion. Ces réseaux de neurones requièrent comme données d’entrée des données satellites de couleur de l’eau co-localisées avec un profil hydrologique collecté par un flotteur Argo. Ils ont été entrainés et validés avec une base de données globale composée de ~5 000 profils de propriétés bio-optiques et hydrologiques acquises par des flotteurs Bio-Argo. Les bases de données utilisées pour développer les méthodes FLAVOR et SOCA proviennent de régions océaniques représentatives de l’océan global, permettant ainsi l’application de ces méthodes à la majorité des eaux océaniques. Finalement, nous avons mené une étude focalisée sur l’Atlantique Nord qui exploite les outils développés. Les champs tridimensionnels de biomasse obtenus, couplés à un modèle bio-optique de production primaire, permettent d’étudier les cycles saisonniers de la distribution verticale de la biomasse phytoplanctonique et de la production primaire dans différentes bio-régions de l’Atlantique NordThis PhD work focuses on the parameterization of the vertical distribution of phytoplankton biomass and community structure in the global open ocean. First we have developed a neural network-based method for the calibration of the fluorescence in chlorophyll a concentration [Chl] associated with the total phytoplankton biomass and with three phytoplankton size classes. This method, (FLAVOR for Fluorescence to Algal communities Vertical distribution in the Oceanic Realm), was trained and validated using a database of ~900 concomitant fluorescence and HPLC-determined pigment profiles. A global database comprising ~49 000 fluorescence profiles was assembled and calibrated with FLAVOR. The resulting database represents a first step towards a global three-dimensional view of phytoplankton biomass and community composition. Second, two neural networks (SOCA for Satellite Ocean Color and Argo data to infer vertical distribution of bio-optical properties) were developed to infer the vertical distribution of two bio-optical proxies of the phytoplankton biomass, [Chl] and the particulate backscattering coefficient, using as input satellite-derived products matched up with a hydrological Argo profile. The SOCA methods were trained and validated using a global database of ~5 000 profiles of bio-optical and hydrological properties collected from Bio-Argo floats with concomitant satellite products. The database used to develop FLAVOR and SOCA originates from various oceanic regions largely representative of the global ocean, making the methods applicable to most oceanic waters. Finally, we proposed a study dedicated to the North Atlantic where the tools developed in this thesis are used in conjunction with a bio-optical primary production model. This allows us to characterize the seasonal cycle of the vertical distribution of the phytoplankton biomass and primary production in various bio-regions of the North Atlantic
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Choe, Hyeong Hun. "Feasibility of intra-articular adeno-associated virus-mediated proteoglycan-4 gene therapy to prevent osteoarthritis." Diss., University of Iowa, 2015. https://ir.uiowa.edu/etd/1836.
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Lubricin, or proteoglycan 4 (PRG4), is a secreted, glycosylated protein that binds to cartilage surfaces, which functions as a boundary lubricant. The loss of lubricin from cartilage is identified as a major pathogenic factor in post-traumatic osteoarthritis (PTOA) that has now been the aim of therapeutic intervention. Intra-articular injection of PRG4 protein provides short-term benefits that might be extended using sustained delivery methods such as in gene therapy.
Here we describe the development and testing of such therapy using adeno-associated virus (AAV) as a vector for the transfer of PRG4-green fluorescent protein (GFP) fusion gene. Our recombinant PRG4 gene produces a PRG4-GFP fusion protein to facilitate tracking of its expression and distribution on joint surfaces. We hypothesized that PRG4-GFP is fully functional as a cartilage lubricant and that PRG4-GFP produced in vivo is expressed by synoviocytes and other joint cells, and cartilage surfaces remained coated for several weeks up to months after intra-articular injection of the virus.
PRG4-GFP showed lubricin-like cartilage binding in vitro, and lubrication immunoblot analysis confirmed that purified PRG4-GFP from cultured media conditioned by PRG4-GFP-transduced synoviocytes was heavily glycosylated, while confocal microscopy revealed binding of the fluorescent fusion protein to cartilage surfaces. Metal-on-cartilage friction tests showed that PRG4-GFP reduced friction coefficients to a degree comparable to that of synovial fluid and had strong chondro-protective effects in explanted cartilage exposed to shear loading. The chondrocyte viability after shear loading showed that PRG4-GFP had a strong chondro-protective effect on par with that of the synovial fluid. Confocal microscopy and immunohistology confirmed that cartilage surfaces in the stifle joints of mice injected with viruses were coated with PRG4-GFP for up to 2 or 4 weeks after the treatment. The overexpression of PRG4-GFP and coating of cartilage surfaces in the stifle joints of mice injected with Adeno-Associated Virus for the transfer of PRG4-GFP fusion gene (AAV-PRG4-GFP) was confirmed by confocal microscopy and immunohistology for up to 2 or 4 weeks post-injection. The μCT imaging and immunohistology in AAV-PRG4-GFP injected rabbit knees showed stronger inhibition in degeneration of damaged tissues than in AAV-GFP injected control group. Collectively these findings indicate that AAV-PRG4-GFP transduction is a valuable new tool for evaluating the effects of long-term lubricant supplementation on PTOA in animal models.
Books on the topic "Fluorescence coefficients"
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Marenkov, O. S. Handbook of photon interaction coefficients in radioisotope-excited x-ray fluorescence analysis. New York: Nova Science Publishers, 1991.
Find full textBook chapters on the topic "Fluorescence coefficients"
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Pfündel, Erhard. "PS I Fluorescence at Room Temperature: Possible Effects on Quenching Coefficients." In Photosynthesis: from Light to Biosphere, 1833–36. Dordrecht: Springer Netherlands, 1995. http://dx.doi.org/10.1007/978-94-009-0173-5_429.
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Nath, Sangeeta, Manli Deng, and Yves Engelborghs. "Fluorescence Correlation Spectroscopy to Determine the Diffusion Coefficient of α-Synuclein and Follow Early Oligomer Formation." In Methods in Molecular Biology, 499–506. Totowa, NJ: Humana Press, 2012. http://dx.doi.org/10.1007/978-1-61779-927-3_29.
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G., Balanagireddy, Ananthajothi K., Ganesh Babu T. R., and Sudha V. "Correlation and Analysis of Overlapping Leukocytes in Blood Cell Images Using Intracellular Markers and Colocalization Operation." In AI Innovation in Medical Imaging Diagnostics, 137–54. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-3092-4.ch008.
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This chapter contributes to the study of uncertainty of signal dimensions within a microscopic image of blood sample. Appropriate colocalization indicator classifies the leukocytes in the region of interest having ragged boundaries. Signal transduction has been interpreted using correlation function determined fluorescence intensity in proposed work using just another colocalization plugin (JaCoP). Dependence between the channels in the colocalization region is being analysed in a linear fashion using Pearson correlation coefficient. Manders split, which gives intensity, is represented in a channel by co-localizing pixels. Overlap coefficients are also being analysed to analyse coefficient of each channel. Li's intensity correlation coefficient is being used in specific cases to interpret the impact of staining.
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D. Bryers, James, and F. Drummond. "Local Mass Transfer Coefficients in Bacterial Biofilms Using Fluorescence Recovery After Photobleaching (FRAP)." In Immobilized Cells - Basics and Applications, Proceedings of an International Symposium organized under auspices of The Working Party on Applied Biocatalysis of the European Federation of Biotechnology Noordwijkerhout, 196–204. Elsevier, 1996. http://dx.doi.org/10.1016/s0921-0423(96)80028-1.
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Morél, Andre. "Optics from the Single Cell to the Mesoscale." In Ocean Optics. Oxford University Press, 1994. http://dx.doi.org/10.1093/oso/9780195068436.003.0009.
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The inherent optical properties of a water body (mesoscale), namely, the absorption coefficient, the scattering coefficient, and the volume scattering function combine with the radiant distribution above the sea to yield the apparent optical properties (Preisendorfer, 1961). The radiative transfer equation is the link between these two classes of optical properties. Locally, the inherent properties of seawater are governed by, and strictly result from, the sum of the contributions of the various components, namely, the water itself, the various particles in suspension able to scatter and absorb the radiant energy, and finally the dissolved absorbing compounds. Analyzing these contributions is an important goal of optical oceanography. Among these particles, the phytoplanktonic cells, with their photosynthetic pigments, are of prime importance, in particular in oceanic waters far from terrestrial influence. They also are at the origin of other kinds of particles, such as their own debris, as well as other living “particles” grazing on them (bacteria, flagellates and other heterotrophs). Studying optics at the level of single cells and particles is therefore a requirement for a better understanding of bulk optical properties of oceanic waters. Independently of this goal, the study of the individual cell optics per se is fundamental when analyzing the pathways of radiant energy, in particular the light harvesting capabilities and the photosynthetic performances of various algae or their fluorescence responses. The following presentation is a guidline for readers who will find detailed studies in the classic books Light Scattering by Small Particles by van de Hulst (1957) and Light and Photosynthesis in Aquatic Ecosystems by Kirk (1983), as well as in a paper dealing specifically with the optics of phytoplankton by Morel and Bricaud (1986). This chapter is organized according to the title, with first a summary of the relevant theories to be applied when studying the interaction of an electromagnetic field with a particle, and then, as a transition between this scale and that of in vitro experiments, some results concerning the optical behavior of pure algal suspensions; finally the more complicated situations encountered in natural environments are briefly described to introduce the “nonlinear biological” effect (Smith and Baker, 1978a) upon the optical coefficients for oceanic waters, and to examine some of the empirical relationships, as presently available, between the pigment concentration and the optical properties of the upper ocean at mesoscale and global scale.
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Carder, Kendall L., and David K. Costello. "Optical Effects of Large Particles." In Ocean Optics. Oxford University Press, 1994. http://dx.doi.org/10.1093/oso/9780195068436.003.0017.
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Two important problems facing the ocean optics research community in the coming decade concern optical model closure and inversion (see Chapter 3). We obtain model closure if we can describe the measured light environment by combining elementary measurements of the optical properties of the medium with radiative transfer theory. If we can accurately deduce the concentration of various constituents from a combination of measures of the submarine light field and inverse model calculations, we term this process model inversion. The most elementary measurements of the optical properties of the sea are those that are independent of the geometry of the light field, the inherent optical properties (Preisendorfer, 1961). Optical properties that are dependent on the geometry of the light field are termed apparent optical properties (AOP). Models of the submarine light field typically relate apparent optical properties to inherent optical properties (see Chapter 2). Examples include the relationship between the AOP irradiance reflectance R and a combination of inherent optical properties (backscattering coefficient bb and absorption coefficient a), and the relationship between the AOP downwelling diffuse attenuation coefficient kd and a combination of the absorption coefficient, backscattering coefficient, and downwelling average cosine μd (e.g., Gordon et al., 1975; Morel and Prieur, 1977; Smith and Baker, 1981; Morel, 1988; Kirk, 1984a). Under some circumstances these relationships work well enough that the absorption coefficient can be derived indirectly. This is important since measurement of the absorption coefficient by direct means has been difficult. Derived values for the absorption coefficient by model inversion methods are not easily verified by independent measurements, however, because of the difficulty of measuring the absorption coefficient. Model closure and model inversion both become more tenuous when the following phenomena are present: 1. Transpectral or inelastic scattering such as fluorescence (e.g., Gordon, 1979; Carder and Steward, 1985; Mitchell and Kiefer, 1988a; Spitzer and Dirks, 1985; Hawes and Carder, 1990) or water Raman scattering (Marshall and Smith, 1990; Stavn, 1990; Stavn and Weidemann, 1988a,b; Peacock et al, 1990; Chapter 12 this volume). 2. Particles that are large relative to the measurement volume for inherent optical property meters such as beam transmissometers, light-scattering photometers, fluorometers, and absorption meters.
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Cesareo, Roberto. "Tables of X-rays Mass Attenuation Coefficients of K and L—Energy, of K, L, and M Fluorescence Yield of Kα/Kβ, Lα/Lβ, and Lα/Lγ Ratios." In Handbook of X-ray Imaging, 1337–66. CRC Press, 2017. http://dx.doi.org/10.1201/9781351228251-69.
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Nitzan, Abraham. "Vibrational Energy Relaxation." In Chemical Dynamics in Condensed Phases. Oxford University Press, 2006. http://dx.doi.org/10.1093/oso/9780198529798.003.0020.
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An impurity molecule located as a solute in a condensed solvent, a solid matrix or a liquid, when put in an excited vibrational state will loose its excess energy due to its interaction with the surrounding solvent molecules. Vibrational energy accumulation is a precursor to all thermal chemical reactions. Its release by vibrational relaxation following a reactive barrier crossing or optically induced reaction defines the formation of a product state. The direct observation of this process by, for example, infrared emission or more often laser induced fluorescence teaches us about its characteristic timescales and their energetic (i.e. couplings and frequencies) origin. These issues are discussed in this chapter. Before turning to our main task, which is constructing and analyzing a model for vibrational relaxation in condensed phases, we make some general observations about this process. In particular we will contrast condensed phase relaxation with its gas phase counterpart and will comment on the different relaxation pathways taken by diatomic and polyatomic molecules. First, vibrational relaxation takes place also in low density gases. Collisions involving the vibrationally excited molecule may result in transfer of the excess vibrational energy to rotational and translational degrees of freedom of the overall system. Analysis based on collision theory, with the intermolecular interaction potential as input, then leads to the cross-section for inelastic collisions in which vibrational and translational/rotational energies are exchanged. If C∗ is the concentration of vibrationally excited molecules and ρ is the overall gas density, the relaxation rate coefficient kgas is defined from the bimolecular rate law When comparing this relaxation to its condensed phase counterpart one should note a technical difference between the ways relaxation rates are defined in the two phases.
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shaolan, Lu, Xu Peizhen, Li Shizhen, Li Jianhua, and Li Mingjie. "APPLICATION OF EMPIRICAL COEFFICIENT METHOD AND COMBINING METHOD OF FUNDAMENTAL PARAMETERS WITH EMPIRICAL COEFFICIENT IN ANALYSIS OF RARE EARTH OXIDES BY X-RAY FLUORESCENCE SPECTROMETRY." In New Frontiers in Rare Earth Science and Applications, 553–56. Elsevier, 1985. http://dx.doi.org/10.1016/b978-0-12-767661-6.50137-5.
Full textConference papers on the topic "Fluorescence coefficients"
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Dertinger, Thomas, Ingo Gregor, Iris von der Hocht, Rainer Erdmann, Benedikt Krämer, Felix Koberling, Rudolf Hartmann, and Jörg Enderlein. "Measuring precise diffusion coefficients with two-focus fluorescence correlation spectroscopy." In Biomedical Optics 2006, edited by Jörg Enderlein and Zygmunt K. Gryczynski. SPIE, 2006. http://dx.doi.org/10.1117/12.651053.
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Bostater, Jr., Charles R., and Jan Rebman. "Wavelength-specific fluorescence coefficients for simulating hyperspectral reflectance signatures of water." In Remote Sensing, edited by Giovanna Cecchi, Edwin T. Engman, and Eugenio Zilioli. SPIE, 1999. http://dx.doi.org/10.1117/12.373140.
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Marschall, Jochen, and Jochen Marschall. "Experimental determination of oxygen and nitrogen recombination coefficients at elevated temperatures using laser-induced fluorescence." In 1997 National Heat Transfer Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 1997. http://dx.doi.org/10.2514/6.1997-3879.
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Samkoe, Kimberley S., Kristian Sexton, Kenneth Tichauer, Scott C. Davis, Julia A. O'Hara, Tayyaba Hasan, and Brian W. Pogue. "Determination of blood plasma fluorescence extinction coefficients for dyes used in three-compartment binding model." In SPIE BiOS, edited by David H. Kessel and Tayyaba Hasan. SPIE, 2011. http://dx.doi.org/10.1117/12.875408.
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Ciocan, E., and R. Ciocan. "Optimized numerical pharmacokinetics model for optical molecular probes based on diffusion coefficients in matrigel measured using fluorescence imaging." In 2009 Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE, 2009. http://dx.doi.org/10.1109/iembs.2009.5332715.
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Sheen, Jyh-Jong, Kuan-Yi Ho, and Yao-Min Lee. "Three-Dimensional Hydrodynamic Focusing With a Circular Microchannel." In ASME 2008 6th International Conference on Nanochannels, Microchannels, and Minichannels. ASMEDC, 2008. http://dx.doi.org/10.1115/icnmm2008-62145.
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We propose a simple method to implement three-dimensional (3D) hydrodynamic focusing with a circular micro-channel for the sample flow. We utilized soft lithography technique and a cylindrical object such as an optical fiber to construct a 3D hydrodynamic focusing master mold made of photoresist and the fiber. The 3D microfluidic focusing device can be duplicated by polydimethylsiloxance (PDMS) casting. When peeling the PDMS cast from the master, there is a crack along the circular channel. However, this crack can be recovered from the thermal bonding of the PDMS cast and a PDMS substrate. We applied this technique to fabricate 3D flow-focusing devices for a microfluidic fluorescence detection chip and a micro-emulsion chip. In the case of microfluidic fluorescence detection, the sample flow can form a small and stable cylindrical flow by controlling the flow rates of sheath flow and sample flow. This allows fluorescent particles to be focused at the center of the channel and to be excited uniformly by laser. Experimental results show that the coefficients of variation for 3D hydrodynamic focusing is 4 to 10 times lower than those of 2D hydrodynamic focusing. As a consequence, the 3D focusing chip provides advantages of stable sample flow and highly uniform detection signals. The micro emulsion chip with 3D hydrodynamic focusing can avoid the wetting problem of two immiscible fluids and successfully produce emulsion droplets.
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Moiseeva, Nataliia, Tanya Churilova, Tatiana Efimova, and Olga Krivenko. "Dependence of fluorescence intensity on chlorophyll a concentration and light absorption coefficients by phytoplankton in the Black Sea (October 2017)." In XXIV International Symposium, Atmospheric and Ocean Optics, Atmospheric Physics, edited by Oleg A. Romanovskii and Gennadii G. Matvienko. SPIE, 2018. http://dx.doi.org/10.1117/12.2505415.
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Gryczynski, Ignacy, Joseph R. Lakowicz, and Jozef Kusba. "End-to-end diffusion coefficients and distance distributions from fluorescence energy transfer measurements: enhanced resolution by using multiple donors with different lifetimes." In OE/LASE '94, edited by Joseph R. Lakowicz. SPIE, 1994. http://dx.doi.org/10.1117/12.182763.
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Wright, Lesley M., and Sara Seitz. "Thermal Development of an Impinging Jet Using Planar Laser Induced Fluorescence (PLIF)." In ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gt2019-92062.
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Abstract Planar Laser Induced Fluorescence (PLIF) has been demonstrated to investigate a round jet impinging on a flat surface. Detailed thermal field distributions have been obtained near the flat target surface to characterize the wall jet development ensuing from the stagnation point. While PLIF has been demonstrated for combustion applications to measure concentration gradients within a mixture, its application for temperature field measurements is less established. Therefore, the technique was applied to a simple, cylindrical impinging jet. The jet Reynolds number varied with Rejet = 5,000–15,000 while the jet–to–target surface spacing varied from H / D = 4–10. The cooling jet (Tjet ∼ 300 K) impinged on a flat, heated surface. The PLIF technique was able to capture the free jet structure and jet development along the target surface. With a short impingement length (H / D = 4), the potential core of the jet strikes the target surface. The thermal gradients captured during the experiments demonstrate the fully turbulent nature of the impinging jet with H / D = 10. The thermal boundary development along the target surface is clearly captured using this fluorescence method. The near wall temperature gradients acquired with the PLIF method have been used to calculate heat transfer coefficients on the heated surface, and these values compare favorably to those measured using a well-established steady state, heat transfer method. The PLIF technique has been demonstrated for this fundamental impingement setup, and it has proven to be applicable to more complex heat transfer and cooling applications.
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Ek, H., W. Proscia, T. Lieuwen, and B. Emerson. "Re-Oriented POD for Feature Extraction From Time Resolved Reacting Flow Datasets." In ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gt2019-90954.
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Abstract Recent improvements in computational and experimental combustion have led to an increased availability of high-fidelity data sets. With the surge of high-quality data, the reduction and analysis of this information become a key aspect in improving our understanding of highly dynamic, reacting flow fields. This work utilizes simultaneous high-speed stereoscopic particle image velocimetry (sPIV), OH-planar laser induced fluorescence (PLIF) and fuel-PLIF measurements in a high pressure, liquid fueled swirl combustor. This work extends one of the most commonly used modal analysis techniques, proper orthogonal decomposition (POD). Instead of decomposing the data as a series of time coefficients and spatial modes, which is the result of snap-shot POD, the data is re-oriented such that the coefficients are a function of the transverse distance and the modes are a function of axial distance and time. This reoriented POD method, referred to as spatio-temporal POD, allows us to directly target convective flow structures while still extracting the same types of information as from snap-shot POD. Additionally, since the modes contain temporal information, phase speeds associated with the convective structures can easily be calculated from the phase portraits. This paper presents results of this analysis, allowing us to track the growth of coherent structures, their phase speeds, and their subsequent decay.
Reports on the topic "Fluorescence coefficients"
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Hubbell, John H. Bibliography and current status of K, L, and higher shell fluorescence yields for computations of photon energy-absorption coefficients. Gaithersburg, MD: National Institute of Standards and Technology, 1989. http://dx.doi.org/10.6028/nist.ir.89-4144.
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