Relevant bibliographies by topics / Atomic fluorescence detection

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

Academic literature on the topic 'Atomic fluorescence detection'

Author: Grafiati
Published: 4 June 2021
Last updated: 12 February 2022

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Journal articles on the topic "Atomic fluorescence detection"

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Zhang, Xiaogang, Shengnan Zhang, Duo Pan, Peipei Chen, Xiaobo Xue, Wei Zhuang, and Jingbiao Chen. "Hanle Detection for Optical Clocks." Scientific World Journal 2015 (2015): 1–6. http://dx.doi.org/10.1155/2015/614737.

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Considering the strong inhomogeneous spatial polarization and intensity distribution of spontaneous decay fluorescence due to the Hanle effect, we propose and demonstrate a universe Hanle detection configuration of electron-shelving method for optical clocks. Experimental results from Ca atomic beam optical frequency standard with electron-shelving method show that a designed Hanle detection geometry with optimized magnetic field direction, detection laser beam propagation and polarization direction, and detector position can improve the fluorescence collection rate by more than one order of magnitude comparing with that of inefficient geometry. With the fixed 423 nm fluorescence, the improved 657 nm optical frequency standard signal intensity is presented. The potential application of the Hanle detection geometry designed for facilitating the fluorescence collection for optical lattice clock with a limited solid angle of the fluorescence collection has been discussed. The Hanle detection geometry is also effective for ion detection in ion optical clock and quantum information experiments. Besides, a cylinder fluorescence collection structure is designed to increase the solid angle of the fluorescence collection in Ca atomic beam optical frequency standard.
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Sabé, Rosa, Roser Rubio, and Lydia Garcı́a-Beltrán. "Selenium determination in urine with atomic fluorescence detection." Analytica Chimica Acta 436, no. 2 (June 2001): 215–21. http://dx.doi.org/10.1016/s0003-2670(01)00966-7.

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D'Ulivo+, A., and S. Rapsomanikis. "Improvements in the Atomic Fluorescence Detection of Mercury." Analytical Letters 30, no. 11 (August 1997): 2109–22. http://dx.doi.org/10.1080/00032719708001725.

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Selwyn, Gary S. "Atomic arsenic detection by ArF laser‐induced fluorescence." Applied Physics Letters 51, no. 3 (July 20, 1987): 167–68. http://dx.doi.org/10.1063/1.98910.

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Lewkowicz, Aneta, Robert Bogdanowicz, Piotr Bojarski, Mattia Pierpaoli, Ignacy Gryczyński, Anna Synak, Michał Mońka, et al. "The Luminescence of 1,8-Diazafluoren-9-One/Titanium Dioxide Composite Thin Films for Optical Application." Materials 13, no. 13 (July 6, 2020): 3014. http://dx.doi.org/10.3390/ma13133014.

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The investigation of innovative label-free α-amino acids detection methods represents a crucial step for the early diagnosis of several diseases. While 1,8-diazafluoren-9-one (DFO) is known in forensic application because of the fluorescent products by reacting with the amino acids present in the papillary exudate, its application for diagnostic purposes has not been fully investigated. The stabilization of DFO over a transparent substrate allows its complexation with biomolecules for the detection of α-amino acids. In this study, DFO was immobilized into a titanium dioxide (TiO2) matrix for the fluorescence detection of glycine, as a target α-amino acid (a potential marker of the urogenital tract cancers). The DFO/TiO2 composite was characterized by atomic force microscopy, spectroscopic ellipsometry, fluorescence spectroscopy and fluorescence microscopy. The performed fluorescent studies indicate spectacular formation of aggregates at higher concentration. The measurements performed using various fluorescence and microscopic techniques together with the suitable analysis show that the aggregates are able to emit short-lived fluorescence.
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Bramanti, Emilia, Chandra Sortino, Cristina Lomonte, Massimo Onor, Roberto Zamboni, Giorgio Raspi, and Alessandro D’Ulivo. "Hydrophobic interaction chromatography coupled with atomic fluorescence spectrometric detection." Talanta 63, no. 2 (May 2004): 383–89. http://dx.doi.org/10.1016/j.talanta.2003.11.002.

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Biedermann, G. W., X. Wu, L. Deslauriers, K. Takase, and M. A. Kasevich. "Low-noise simultaneous fluorescence detection of two atomic states." Optics Letters 34, no. 3 (January 29, 2009): 347. http://dx.doi.org/10.1364/ol.34.000347.

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Masamba, W. R., B. W. Smith, R. J. Krupa, and J. D. Winefordner. "Atomic and Ionic Fluorescence in an Inductively Coupled Plasma Using Hollow Cathode Lamps Pulsed at High Currents as Excitation Sources." Applied Spectroscopy 42, no. 5 (July 1988): 872–78. http://dx.doi.org/10.1366/0003702884428851.

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Hollow cathode lamps pulsed at high currents were used as atomic and ionic fluorescence sources to excite atoms and ions in an inductively coupled plasma. Atomic fluorescence was measured for Cu, Ag, Zn, Al, Cr, and Mo, while ionic fluorescence was measured for Cu, Cr, Zn, and Sr. Limits of detection for atomic fluorescence were found to be better than those obtained by a commercial atomic fluorescence instrument operated under the same conditions, and calibration curves were linear over a range of approximately 104.
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Smith, Benjamin W., Mark R. Glick, Ken N. Spears, and James D. Winefordner. "A Comprehensive Table of Atomic Fluorescence Detection Limits and Experimental Conditions." Applied Spectroscopy 43, no. 3 (March 1989): 376–414. http://dx.doi.org/10.1366/0003702894202896.

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A comprehensive table of atomic fluorescence spectrometry results has been compiled and arranged by element. Data tabulated include excitation and fluorescence wavelengths, atom reservoir, excitation source, limits of detection, and comments concerning experimental peculiarities and types of samples analyzed.
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Pappas, Dimitri, Tiffany L. Correll, Nathan C. Pixley, Benjamin W. Smith, and J. D. Winefordner. "Detection of Mie Scattering Using a Resonance Fluorescence Monochromator." Applied Spectroscopy 56, no. 9 (September 2002): 1237–40. http://dx.doi.org/10.1366/000370202760295502.

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The use of a resonance fluorescence monochromator (RFM) is described as a method for detecting Mie scatter. The detector has a spectral resolution limited by the atomic vapor used in the system (400 MHz for cesium). The RFM is used to detect Mie scatter from a particulate suspension, and deconvolution methods are used to extract the Mie scatter spectrum from the instrument response. The Mie scattering linewidth (140 MHz) is close to the literature value (100 MHz for air). Methods to reduce the linewidth of atomic vapor filters are briefly described.
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Dissertations / Theses on the topic "Atomic fluorescence detection"

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Alli, Azaam. "Analysis of organomercurials in environmental and biological samples by capillary column gas chromatography with atomic fluorescence detection." FIU Digital Commons, 1994. http://digitalcommons.fiu.edu/etd/1069.

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The general method for determining organomercurials in environmental and biological samples is gas chromatography with electron capture detection (GC-ECD). However, tedious sample work up protocols and poor chromatographic response show the need for the development of new methods. Here, Atomic Fluorescence-based methods are described, free from these deficiencies. The organomercurials in soil, sediment and tissue samples are first released from the matrices with acidic KBr and cupric ions and extracted into dichloromethane. The initial extracts are subjected to thiosulfate clean up and the organomercury species are isolated as their chloride derivatives by cupric chloride and subsequent extraction into a small volume of dichloromethane. In water samples the organomercurials are pre-concentrated using a sulfhydryl cotton fiber adsorbent, followed by elution with acidic KBr and CuSO 4 and extraction into dichloromethane. Analysis of the organomercurials is accomplished by capillary column chromatography with atomic fluorescence detection.
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Májska, Milada. "Role sedimentů jako zdroje nebo úložiště znečištění rtutí, geochemická studie." Doctoral thesis, Vysoké učení technické v Brně. Fakulta chemická, 2011. http://www.nusl.cz/ntk/nusl-233329.

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Rtuť je v přírodě přirozeně se vyskytujícím toxickým prvkem, jehož globální emise jsou ovlivňovány zejména antropogenními zdroji znečištění. Obrovský globální nárůst v usazování rtuti, zejména ve vodných ekosystémech, byl zaznamenán současně s počátkem průmyslové revoluce. Sedimenty jsou posledním místem úložiště nejrůznějších komplexů rtuti. Rtuť však zde může být přeměněna na toxičtější organickou formu, methylrtuť, pomocí transformačních procesů kontrolovaných různými fyzikálními, chemickými, ale i biologickými faktory. Navíc mohou být specie rtuti remobilizovány ze sedimentů pomocí difuze a resuspenzace a tak se sedimenty mohou stát i potenciálním zdrojem rtuti. Proces bioakumulace a bioobohacování tak pokračuje v potravním řetězci, ve kterém se člověk, i další zvířata, stává konzumentem methylrtuti. Stanovení celkové koncentrace rtuti není dostačující k porozumění osudu rtuti v přírodním prostředí a tak stanovení MeHg poskytuje nezbytnou doplňující informaci. Dostatečně citlivá a přesná analytická metoda pro stanovení specií rtuti je nezbytným nástrojem environmentální chemie. Metody vhodné pro stanovení specií rtuti v sedimentech jsou popsány v části metodologie disertační práce. Metoda stanovení methylrtuti v sedimentech pomocí automatické Headspace vybavené pastí („trap“) a spojené s plynovou chromatografií a fluorescenční detekcí je zde také popsána. Zvláštní pozornost je také věnována potřebám zásad čistého vzorkování, skladování vzorků a přípravě vzorků před samotou analýzou, jakož i samostatné části věnující se terénní studii rtuti a methylrtuti v sedimentech vytipovaných lokalit. Sedimenty jižní Moravy a severní Francie jsou srovnány z hlediska znečištění rtutí. Specie rtuti a další ukazatele (Fe, Mn, S) byly analyzovány v sedimentech, pórové vodě a povrchové vodě řek Dele a Lys (Francie) a Jihlava a Morava (Česká republika). Z hlediska posouzení vodních ekosystémů a jejich znečištění rtutí, je vhodné znát koncentraci rtuti v pórové vodě a posoudit dostupnost rtuti ze sedimentů. Technika difuzního gradientu v tenkém filmu je vhodným způsobem jak stanovit koncentraci rtuti v pórové vodě sedimentů. Do roku 2005 bylo použití této techniky pro měření rtuti značně limitováno. Ale nedávný pokrok především v dostupnosti možných sorpčních gelů vhodných pro stanovení rtuti umožnilo využití této techniky i pro stanovení rtuti. Byly použity různé sorpční gely: Spheron.Thiol, Duolite GT-73 a TiO2. Řeka Dele představuje past enormního množství antropogenní rtuti pocházející z průmyslových zdrojů a je považována za potenciální významný zdroj methylrtuti pro okolní prostředí a živé organismy především. Poslední část dizertační práce se zabývá aplikací dobře zavedeného experimentu využívajícím stabilní isotopy ke studiu metylačních a demethylačních procesů v sedimentech řeky Dele. Obohacené stabilní značkovače rtuti v anorganické formě (199Hg) and methylované formě (201MeHg) byly přidány do sedimentů. Tyto označené specie rtuti tak pomohly sledovat osud specií rtuti a vypočítat rozsah jejich přeměny v průběhu experimentu.
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Skogeby, Richard. "Performance assessment of fluorescent nuclear track detectors in physically optimised spread-out Bragg peaks : Carried out at the German Cancer Research Center." Thesis, Umeå universitet, Radiofysik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-144482.

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Clinical heavy ion beams provide the most accurate means of external radiation treatment of tumors available. The study of energetic heavy ions on individual cells have been hampered by shortcomings in available detector technology. The fluorescence nuclear track detector developed by the Landauer Inc. is a small chiplike detector with all the properties needed for these kinds of studies. It is biocompatible, autoclavable, does not require post-irradiation chemical processingand allows the readout of a sufficient number of physical parameters for the determination of a particle’s radiobiological and physical properties. Previous studies in clinical spread-out Bragg peaks have shown a discrepancy in what is detected to what is seen in Monte Carlo radiation transport simulations. While the fluence of heavy primary ions agrees to within one percent, the detection of fragments is underestimated by at least an order of magnitude. In this thesis the performance of the track-recording has been assessed for light ion fragmentsfrom hydrogen, helium and carbon primary particles in physically optimised spread-out Braggpeaks. The underestimation of light ion fragments for carbon beams, mentioned in previousstudies, was reproduced. The underestimation of light ion fragments is prevalent also for helium primary particles. No significant amount of lost tracks are seen in hydrogen beams. The analysis verifies the hypothesis that the detection of large angle trajectories for light ion fragments is not a principal limitation of the detector. The underestimation most probably stems from some limiting features of the readout and image analysis procedure.
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Nguyen, Van Liem, Henrik Tollin, and Thanh Tu Tran. "Coupling of a home-made simulated automatic mercury analyzer (AMA254) to a mercury fluorescence detector for total mercury determination in biological samples : -The use of a hydride generator system and atomic absorption spectroscopy to detect mercury in water samples." Thesis, Umeå universitet, Kemiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-56597.

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In this project we have been working with two different instruments home-made AMA 254 and Hydride Generator. Home-made AMA 254 was coupled to a fluorescence detector. The Hydride Generator was coupled to atomic absorption spectroscopy (AAS), by an optical path. Calibration of mass-flow controller by applying a suitable gas in the inlet and a bubbles calibration unit at the outlet. All date was saved by labview program was used The first configurations, carrier gas was fed into the middle of the catalyzer tube and the gold-trap by a T-shape connector to carry mercury to the detector. Condensation of mercury vapour when the gas-stream collided to the silicon walls, at the T-shape connection leads to failing. Second configuration, two positioned-switching valve was introduced between the oxygen and argon tanks, allowing only one gas to reach MFC depending on the switching position. There are four different parameters memory effects, repeatability, accuracy and sensitivity, have to investigated to know that the machine gives reliable result when running real samples. Memory effects: Memory effect is one reason for deviation of the analysis. It is obvious that some mercury still remains within the tube after running. Memory effect is not significant at high concentration of the analyte, but could be troublesome at lower concentration. Repeatability: Repeatability was tested by running 3 replicates with the same concentration of the analyte. This is important for knowing the precision of the analysis. Accuracy: The Reference material MESS-92 (92ppb) was used to evaluate the accuracy of the analysis . Triplicate was running and the mean value was calculated to 98.3 ppb, the deviation was 6.86%. Sensitivity: By comparing the mercury fluorescence detector and atomic absorption (AAS) it become evident that the fluorescence detector is much more suitable for analysis with AMA 254 as it gave an overloaded signal whereas the atomic absorption only appeared as noise. Minor Field Study in Chemistry – Autumn 2010 Page 4 The comparison between the mercury fluorescence detector and atomic absorption (AAS) was done with 0.05 gram(g) tuna fish samples. Mercury fluorescence detector gave an overloaded signal, whereas the AAS signal appeared as noise. It is evident that the fluorescence detector is much more sensitive than the AAS detector. Hydride generation is one common method for determining mercury in water. Three different channels are used for pumping the solutions and forming hydride, they are Hydrochloric acid, NaBH4and sample (blank, standards). The hydride form of mercury was flushed and collected into the gold trap by nitrogen gas. After that the gold-trap is heated up to release mercury optical cell where the absorption as a peak was measured in the same manner as normal flame AAS without using of flame. In our project we also made up a temperature controller to control the temperature. The real temperature was measured by thermocouple and was designed like a small box.
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Tsai, Jeng-Shiun, and 蔡政勳. "STUDY OF DETECTION LIMIT BY FLAME LASER-EXCITED ATOMIC FLUORESCENCE SPECTROMETRY." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/36994008014245167711.

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Hui-Wen, Hung, and 洪惠雯. "Detection Limit of Ba and Tl by Flame Laser-Excited Atomic Fluorescence Spectrometry." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/77828222412267840150.

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碩士
國立成功大學
化學系
87
Flame laser-excited atomic fluorescence spectrometry (FLAFS) has been shown an excellent method for trace metal detection and quantitative analysis among the region of laser-induced fluorescence (LIF) spectroscopy. In this study, a continuous wave (CW) dye laser has been employed as the excitation source for atoms produced by flame atomizer from a ground state to an excited state, and the laser induced fluorescence has been detected by a system including optical fiber, monochromator, PMT, and lock-in amplifier. The excitation wavelengths of barium is 554.0nm. The detection limit for barium ion in our method is < 0.1 ppb.
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Asiaei, Sasan. "Microfluidic-Based In-Situ Functionalization for Detection of Proteins in Heterogeneous Immunoassays." Thesis, 2013. http://hdl.handle.net/10012/7211.

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One the most daunting technical challenges in the realization of biosensors is functionalizing transducing surfaces for the detection of biomolecules. Functionalization is defined as the formation of a bio-compatible interface on the transducing surfaces of bio-chemical sensors for immobilizing and subsequent sensing of biomolecules. The kinetics of functionalization reactions is a particularly important issue, since conventional functionalization protocols are associated with lengthy process times, from hours to days. The objective of this thesis is the improvement of the functionalization protocols and their kinetics for biosensing applications. This objective is realized via modeling and experimental verification of novel functionalization techniques in microfluidic environments. The improved functionalization protocols using microfluidic environments enable in-situ functionalization, which reduces the processing times and the amount of reagents consumed, compared to conventional methods. The functionalization is performed using self-assembled monolayers (SAMs) of thiols. The thiols are organic compounds with a sulphur group that assists in the chemisorption of the thiol to the surface of metals like gold. The two reactions in the functionalization process examined in this thesis are the SAM formation and the SAM/probe molecule conjugation. SAM/probe molecule conjugation is the chemical treatment of the SAM followed by the binding of the probe molecule to the SAM. In general, the probe molecule is selective in binding with a given biomolecule, called the target molecule. Within this thesis, the probe molecule is an antibody and the target molecule is an antigen. The kinetics of the reaction between the probe (antibody) and the target biomolecule (antigen) is also studied. The reaction between an antigen and its antibody is called the immunoreaction. The biosensing technique that utilizes the immunoreaction is immunoassay. A numerical model is constructed using the finite element method (FEM), and is used to study the kinetics of the functionalization reactions. The aim of the kinetic studies is to achieve both minimal process times and reagents consumption. The impact of several important parameters on the kinetics of the reactions is investigated, and the trends observed are explained using kinetic descriptive dimensionless numbers, such as the Damköhler number and the Peclet number. Careful numerical modeling of the reactions contributes to a number of findings. A considerably faster than conventional SAM formation protocol is predicted. This fast-SAM protocol is capable of reducing the process times from the conventional 24-hours to 15 minutes. The numerical simulations also predict that conventional conjugation protocols result in the overexposure of the SAM and the probe molecule to the conjugation reagents. This overexposure consequently lowers conjugation efficiencies. The immunoreaction kinetics of a 70 kilo-Dalton heat shock protein (HSP70) with its antibody in a hypothetical microchannel is also investigated through the FEM simulations. Optimal reaction conditions are determined, including the flow velocity and the surface concentration of the immobilized probes (antibodies). Based on the numerical results and a series of experimental studies, the fast-SAM protocol application is successfully confirmed. Moreover, the optimum reagent concentration for a given one- hour conjugation process time is determined. This functionalization protocol is successfully applied to immobilize the HSP70 antibody on gold surfaces. The use of the fast-SAM protocol and the predicted optimum conjugation conditions result in binding of the HSP70 antibody on gold, with the same or superior immobilization quality, compared to the conventional protocols. Upon implementation of a 70 μm.s^(-1) flow velocity, the reaction is observed to complete in around 30-35 minutes, which is close to the numerically predicted 30 minutes and 16 seconds. This immunoreaction time is considerably less than conventional 4-12 hour processes. The modified in-situ functionalization techniques achieved here are promising for substantially reducing the preparation times and improving the performance of biosensors, in general, and immunoassays, in particular.
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Books on the topic "Atomic fluorescence detection"

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DeWild, John F. Determination of methyl mercury by aqueous phase ethylation, followed by gas chromatographic separation with cold vapor atomic fluorescence detection. Middleton, Wis: U.S. Dept. of the Interior, U.S. Geological Survey, 2002.

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Hueber, Dennis Michael. Excimer laser excited atomic fluorescence detection of arsenic, and the design and characterization of a flowing electrolytic hydride generator for arsenic and selenium analysis. 1994.

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L, Olson Mark, Olund Shane D, and Geological Survey (U.S.), eds. Determination of methyl mercury by aqueous phase ethylation, followed by gas chromatographic separation with cold vapor atomic fluorescence detection. Middleton, Wis: U.S. Dept. of the Interior, U.S. Geological Survey, 2002.

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Book chapters on the topic "Atomic fluorescence detection"

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Goldsmith, J. E. M. "Two-Step Saturated Fluorescence Detection of Atomic Hydrogen in Flames." In Springer Series in Optical Sciences, 410–11. Berlin, Heidelberg: Springer Berlin Heidelberg, 1985. http://dx.doi.org/10.1007/978-3-540-39664-2_128.

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Krishnan, Kannan M. "Atomic Structure and Spectra." In Principles of Materials Characterization and Metrology, 68–146. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198830252.003.0002.

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We review the structure of atoms to describe allowed intra-atomic electronic transitions following dipole selection rules. Inner shell ionization is followed by characteristic X-ray emission or non-radiative de-excitation processes leading to Auger electrons that involve three atomic levels. Photon incidence also results in characteristic photoelectron emission, reflecting the energy distribution of the electrons in the solid. We present details of laboratory and synchrotron sources of X-rays, and discuss their detection by wavelength or energy-dispersive spectrometers, as well as microanalysis with X-ray (XRF), or electron (EPMA) incidence. Characteristic X-ray intensities are quantified in terms of composition using corrections for atomic number (Z), absorption (A), and fluorescence (F). Electron detectors use electrostatic or magnetic dispersing fields; two common designs are electrostatic hemispheric or mirror analyzers. Auger electron spectroscopy (AES) and X-ray photoelectron spectroscopy (XPS), used for surface analysis, require ultra-high vacuum. AES is a weak signal, best resolved in a derivative spectrum, shows sensitivity to the chemical state and the atomic environment, provides a spatially-resolved signal for composition mapping, and can be quantified for chemical analysis using sensitivity factors. Finally, we introduce the basics of XPS, a photon-in, electron-out technique, discussed further in §3.
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Shapiro, Howard M. "Fluorescent Probes." In Flow Cytometry for Biotechnology. Oxford University Press, 2005. http://dx.doi.org/10.1093/oso/9780195183146.003.0006.

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In the jargon of cytometry, cellular characteristics, such as size, nucleic acid content, and membrane potential, are usually referred to as parameters, a term that is also used for the physical characteristics, such as absorption, light scattering, and fluorescence intensity, that are measured by cytometric instrumentation. Fluorescence, as a physical parameter, plays a key role in the detection of probes on beads for multiplexed analysis. Cellular parameters can be classed as intrinsic or extrinsic. Intrinsic cellular parameters are those that can be measured without the use of a reagent; measurement of extrinsic parameters requires the use of reagents, which are almost always referred to as probes, thereby occasioning confusion among molecular biologists new to cytometry. Cellular parameters are also characterized as structural or functional; DNA and RNA content and the presence and copy number of an antigen or nucleic acid sequence are structural parameters, whereas internal pH, membrane potential, and enzyme activity are functional parameters. The distinction between structural and functional parameters blurs at the edge, but the concept has been generally useful. Fluorescent probes allow measurement of the widest variety of extrinsic cellular parameters. For an atom or molecule to fluoresce, it must first absorb a photon, raising an electron to a higher energy level that is known as an excited state. Excitation by absorption requires only about a femtosecond. Fluorescence occurs when the electron loses all or some of the absorbed energy by emission of a photon. The fluorescence lifetime, that is, the period between excitation and emission, is typically on the order of a few nanoseconds for fluorescent organic materials but is notably longer (hundreds of microseconds) for some materials (e.g., lanthanide chelates). In almost all cases, some of the excitation energy is lost nonradiatively by transitions between different vibrational energy levels of the electronic excited state; this loss requires that the emitted energy be less than the energy absorbed, meaning that the fluorescence emission will be at a longer wavelength than the excitation. The difference between the principal excitation and emission maxima in the fluorescence spectrum is known as the Stokes shift, honoring George Stokes, who first described fluorescence in the mid-1800s. Typical Stokes shifts are no more than a few tens of nanometers.
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Szabo, Arthur G. "Fluorescence principles and measurement." In Spectrophotometry and Spectrofluorimetry. Oxford University Press, 2000. http://dx.doi.org/10.1093/oso/9780199638130.003.0006.

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Fluorescence spectrometry is the most extensively used optical spectroscopic method in analytical measurement and scientific investigation. During the past five years more than 60000 scientific articles have been published in which fluorescence spectroscopy has been used. The large number of applications ranges from the analytical determination of trace metals in the environment to pH measurements in whole cells under physiological conditions. In the scientific research laboratory, fluorescence spectroscopy is being used or applied to study the fundamental physical processes of molecules; structure-function relationships and interactions of biomolecules such as proteins and nucleic acids; structures and activity within whole cells using such instrumentation as confocal microscopy; and DNA sequencing in genomic characterization. In analytical applications the use of fluorescence is dominant in clinical laboratories where fluorescence immunoassays have largely replaced radioimmunoassay techniques. There are two main reasons for this extensive use of fluorescence spectroscopy. Foremost is the high level of sensitivity and wide dynamic range that can be achieved. There are a large number of laboratories that have reported single molecule detection. Secondly, the instrumentation required is convenient and for most purposes can be purchased at a modest cost. While improvements and advances continue to be reported fluorescence instrumentation has reached a high level of maturity. A review of the physical principles of the fluorescence phenomenon permits one to understand the origins of the information content that fluorescence measurements can provide. A molecule absorbs electromagnetic radiation through a quantum mechanical process where the molecule is transformed from a ‘ground’ state to an ‘excited’ state. The energy of the absorbed photon of light corresponds to the energy difference between these two states. In the case of light in the ultraviolet and visible spectral range of 200 nm to 800 nm that corresponds to energies of 143 to 35.8 kcal mol-1. The absorption of light results in an electronic transition in the atom or molecule. In atoms this involves the promotion of an electron from an outer shell orbital to an empty orbital of higher energy.
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Blow, David. "Diffraction." In Outline of Crystallography for Biologists. Oxford University Press, 2002. http://dx.doi.org/10.1093/oso/9780198510512.003.0008.

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Diffraction refers to the effects observed when light is scattered into directions other than the original direction of the light, without change of wavelength. An X-ray photon may interact with an electron and set the electron oscillating with the X-ray frequency. The oscillating electron may radiate an X-ray photon of the same wavelength, in a random direction, when it returns to its unexcited state. Other processes may also occur, akin to fluorescence, which emit X-rays of longer wavelengths, but these processes do not give diffraction effects. Just as we see a red card because red light is scattered off the card into our eyes, objects are observed with X-rays because an illuminating X-ray beam is scattered into the X-ray detector. Our eye can analyse details of the card because its lens forms an image on the retina. Since no X-ray lens is available, the scattered X-ray beam cannot be converted directly into an image. Indirect computational procedures have to be used instead. X-rays are penetrating radiation, and can be scattered from electrons throughout the whole scattering object, while light only shows the external shape of an opaque object like a red card. This allows X-rays to provide a truly three-dimensional image. When X-rays pass near an atom, only a tiny fraction of them is scattered: most of the X-rays pass further into the object, and usually most of them come straight out the other side of the whole object. In forming an image, these ‘straight through’ X-rays tell us nothing about the structure, and they are usually captured by a beam stop and ignored. This chapter begins by explaining that the diffraction of light or X-rays can provide a precise physical realization of Fourier’s method of analysing a regularly repeating function. This method may be used to study regularly repeating distributions of scattering material. Beginning in one dimension, examples will be used to bring out some fundamental features of diffraction analysis. Graphic examples of two-dimensional diffraction provide further demonstrations. Although the analysis in three dimensions depends on exactly the same principles, diffraction by a three-dimensional crystal raises additional complications.
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"about chemical bonding and molecular structure. This information can be used to detect th e types of organic materials present on the surface. 4.3.2.2. Raman spectroscopy (RS) [7, 8] It is used to examine the energy levels of molecules that cannot be well character-ized via infrared spectroscopy. Th e two techniques, however, are complimentary. In the RS, a sample is irradiated with a strong monochromatic light source (usu-ally a laser). Most of the radiation will scatter or "reflect off' the sample at the same energy as the incoming laser radiation. However, a small amount will scat-ter from the sample at a wavelength slightly shifted from the original wavelength. It is possible to study the molecular structure or determine the chemical identity of the sample. It is quite straightforward to identify compounds by spectral library search. Due to extensive library spectral information, the unique spectral finger-print of every compound, and the ease with which such analyses can be per-formed, the RS is a very useful technique for various applications. An important application of the RS is the rapid, nondestructive characterization of diamond, diamond-like, and amorphous-carbon films. 4.3.2.3. Scanning electron microscopy (SEM) / energy dispersive X-ra y analysis (EDX) [7, 8] The SEM produce s detailed photographs that provide important information about the surface structure and morphology of almost any kind of sample. Image analy-sis is often the first and most important step in problem solving and failure analy-sis. With SEM, a focused beam of high-energy electrons is scanned over the sur-face of a material, causing a variety of signals, secondary electrons, X-rays, photons, etc. - each of which may be used to characterize the material with re-spect to specific properties . The signals are used to modulate the brightness on a CRT display, thereb y providing a high-resolution map of the selected material property. It is a surface imaging technique, but with Energy Dispersive X-ray (EDX) it can identify elements in the near-surface region. This technique is most useful for imaging particles. 4.3.2.4. X-ray fluorescence (XRF) [7, 8] Incident X-rays are used to excite surface atoms. The atoms relax through the emission of an X-ray with energy characteristic of the parent atoms and the inten-sity proportional to the amount of the element present. It is a bulk or "total mate-rials" characterization technique for rapid, simultaneous, and nondestructive analysis of elements having an atomic number higher than that of boron. Tradi-tional bulk analysis applications include identifying metals and alloys, detecting trace elements in liquids, and identifying residues and deposits. 4.3.2.5. Total-reflection X-ray fluorescence (TXRF) [7, 8] It is a special XRF technique that provides extremely sensitive measures of the elements present in a material's outer surface. Applications include searching for metal contamination in thin films on silicon wafers and detecting picogram-levels o f arsenic, lead, mercury and cadmium on hazardous, chemical fume hoods." In Surface Contamination and Cleaning, 43–45. CRC Press, 2003. http://dx.doi.org/10.1201/9789047403289-9.

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Conference papers on the topic "Atomic fluorescence detection"

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Hüwel, L., A. M. Wodtke, P. Andresen, and H. Voges. "Position sensitive detection with laser induced fluorescence." In The Sixteenth International Conference on the Physics of Electronic and Atomic Collisions. AIP, 1990. http://dx.doi.org/10.1063/1.39276.

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Lu, Y. F., X. K. Shen, and H. Ling. "Laser-Induced Breakdown Spectroscopy Combined With Spatial Confinement of Plasmas and Laser-Induced Fluoresence for Trace-Materials Detection." In ASME 2009 Second International Conference on Micro/Nanoscale Heat and Mass Transfer. ASMEDC, 2009. http://dx.doi.org/10.1115/mnhmt2009-18354.

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Laser-induced breakdown spectroscopy (LIBS) with spatial confinement effects and LIBS combined with laser-induced fluorescence (LIBS-LIF) have been investigated to improve the detection sensitivity and element-selectivity of LIBS. An obvious enhancement in the emission intensity of aluminum (Al) atomic lines was observed when a cylindrical wall was placed to spatially confine the plasma plumes. The maximum enhance factor for the emission intensity of Al atomic lines was measured to be around 10. Assuming local thermodynamic equilibrium conditions, the plasma temperatures are estimated to be in a range from 4,000 to 5,800 K. It shows that the plasma temperature increased by around 1,000 K when the cylindrical confinement was applied. Fast images of the laser-induced Al plasmas show that the plasmas were compressed into a smaller volume with a pipe presented. LIBS-LIF has been investigated to overcome the matrix effects of LIBS for the detection of trace uranium (U) in solids. An optical parametric oscillator wavelength-tunable laser was used to resonantly excite the uranium atoms and ions within the plasma plumes generated by a Q-switched Nd:YAG laser. Both atomic and ionic lines can be selected to detect their fluorescence lines. A U concentration of 462 ppm in a glass sample can be detected using this technique at an excitation wavelength of 385.96 nm for resonant excitation of U II and a fluorescence line wavelength of 409.01 nm from U II. The mechanism of spatial confinement effects and the influence of relevant operational parameters of LIBS-LIF are discussed. In this work, detection in open air of trace phosphorus (P) in steels using LIBS-LIF has also been investigated. The optical parametric oscillator laser was used to resonantly excite the P atoms within plasma plumes generated by the Q-switched Nd:YAG laser. A set of steel samples with P concentrations from 3.9 to 720 ppm were analyzed using LIBS-LIF at wavelengths of 253.40 and 253.56 nm for resonant excitation of P atoms and fluorescence lines at wavelengths of 213.55 and 213.62 nm. The calibration curves were measured to determine the limit of detection for P in steels, which is estimated to be around 0.7 ppm.
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Wang, Y. H., Y. Gu, J. Q. Huang, S. Q. Liu, T. Q. Dong, and Z. H. Lu. "Proposal of rubidium atomic beam clock based on lamp pumped and fluorescence detection." In 2011 Joint Conference of the IEEE International Frequency Control and the European Frequency and Time Forum (FCS). IEEE, 2011. http://dx.doi.org/10.1109/fcs.2011.5977301.

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Jia, Yaqing, Hong Wu, and Zhengsheng Shen. "Research on method and device of non-disperse atomic fluorescence excitation light source impurity detection." In International Symposium on Optoelectronic Technology and Application 2016, edited by Sen Han and JiuBin Tan. SPIE, 2016. http://dx.doi.org/10.1117/12.2245022.

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Löfström, C., J. Engström, M. Richter, C. F. Kaminski, P. Johansson, K. Nyholm, J. Hult, J. Nygren, and M. Aldén. "Feasibility Studies and Application of Laser /Optical Diagnostics for Characterisation of a Practical Low-Emission Gas Turbine Combustor." In ASME Turbo Expo 2000: Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/2000-gt-0124.

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The present paper presents applications and feasibility studies of a number of laserspectroscopic techniques in a lean premixed prevaporised (LPP) combustor. Four different laser diagnostic techniques were investigated. The two more mature techniques, Planar Mie Scattering/Laser Induced Fluorescence and Planar Laser Induced Fluorescence of OH were used for fuel- and OH-visualisation, respectively. In addition, the applicability of some novel techniques in harsh industrial environments were investigated, two-line atomic fluorescence (TLAF) to obtain 2-dimensional temperature distributions, and two-photon LIF for the detection of CO. In order to investigate the degree of turbulence an ultrafast framing camera was employed to record spontaneous emission.
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Kulatilaka, Waruna D., Robert P. Lucht, and Thomas B. Settersten. "Investigation of Two-Color Laser-Induced Fluorescence (TC-LIF) and Two-Color Six-Wave Mixing Spectroscopy (TC-SWM) for Detection of Atomic Hydrogen." In Laser Applications to Chemical, Security and Environmental Analysis. Washington, D.C.: OSA, 2006. http://dx.doi.org/10.1364/lacsea.2006.thc5.

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Strobl, Jeannine S., Mehdi Nikkhah, Robert Rhoades, and Masoud Agah. "Effects of an Experimental Drug, Suberoylanilide Hydroxamic Acid (SAHA), on Attachment, Spreading, and Stiffness of Human Breast Cancer Cells on Silicon Substrates." In ASME 2010 First Global Congress on NanoEngineering for Medicine and Biology. ASMEDC, 2010. http://dx.doi.org/10.1115/nemb2010-13037.

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We are investigating silicon-based platforms for detection and analysis of breast cancer cells. Attachment and spreading of MDA-MB-231 human metastatic breast cancer cells was compared to that of non-tumorigenic human breast epithelial cells, MCF-10A, and the impact of SAHA (Vorinostat), a histone deacetylase (HDAC) inhibitor, on cell behaviors was ascertained. Our results showed the cancer cells attached to flat silicon and PECVD nitride-coated silicon more efficiently than non-cancer cells, and preferential cancer cell attachment was enhanced by SAHA. Fluorescent immunohistochemistry (IHC) revealed that SAHA stimulated actin stress fiber formation and focal adhesion to the substrates; atomic force microscopy (AFM) showed SAHA increased the cancer cell stiffness. Collectively, SAHA-induced biomechanical changes altered the cell morphology and mode of attachment to flat silicon and to three-dimensional silicon microstructures. This is the first report of the use of AFM to characterize the biomechanical effects of a HDAC inhibitor in cancer cells.
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Mahon, Christopher, Dwayne Heard, Michael Brown, Gregory Smith, and Jay Jeffries. "Laser-induced fluorescence and amplified spontaneous emission detection of hydrogen atoms in flames." In 34th Aerospace Sciences Meeting and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 1996. http://dx.doi.org/10.2514/6.1996-465.

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Sitdikov, Vil Dayanovich, Artyom Anatolyevich Nikolaev, Ekaterina Alekseevna Kolbosenko, Grigoriy Vladimirovich Ivanov, Artyom Konstantinovich Makatrov, and Andrey Vladimirovich Malinin. "The Features of X-Ray Phase Analysis of Rocks with Complex Mineral Composition." In SPE Symposium: Petrophysics XXI. Core, Well Logging, and Well Testing. SPE, 2021. http://dx.doi.org/10.2118/208448-ms.

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Abstract The article presents the results of identification and quantitative analysis of the phase composition, fine structure parameters of minerals in carbonate and terrigenous rocks by the use of modern X-ray diffraction (XRD) analysis. To make the XRD analysis, we optimized the modes of x-ray pattern shooting by changing the radius of the goniometer, the system of primary and secondary slits, Soller slits, and the system of detecting the low-content minerals. In processing the obtained x-ray patterns, we considered the size and defects of the crystal grains, the crystallographic mode of arrangements, atomic population of the crystal lattice, the Debye-Waller factor and the instrumental line broadening by the use of the Caliotti function for LaB6. So we determined the type and content of minerals, estimated the period of the crystal lattice, the size of the coherent scattering domains and micro-distortion crystal lattice of the mineral. We compared the obtained data on the presence and quantitative content of minerals with the data of X-ray fluorescence (XRF) analysis and scanning electron microscopy (SEM). Based on the obtained data, reference intensity ratio (RIR) coefficients were selected for a number of minerals typically contained in core materials for quantitative phase analysis by the use of the corundum number method.
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