Fluorescence spectrometer for

Desnica, V. and Schreiner, M. (2006). A LabVIEW-controlled portable X-ray fluorescence spectrometer for the analysis of art objects. X-Ray Spectrometry 35 280-286. 

S. Arnold and L. M. Folan, Fluorescence spectrometer for a single electrodynamically levitated microparticle, Rev. Sci. Instrum 57, 2250-2253 (1986). 

Seven previously analyzed Claudian quadrantes (9) are fairly close in composition to the ones reported in this chapter. However, improved analytical techniques and use of a better x-ray fluorescence spectrometer for nickel, silver, and lead analyses have produced results that are probably more accurate than the previous ones. 

The 30-mm sediment slices of the segmented cylindrical cores obtained from box coring at the seven stations were dried, pulverized, and thoroughly mixed to yield a uniform sample for analysis. Sediment from each of these slices was analyzed by two independent methods. The first method used a Perkin-Elmer model 5000 atomic absorption spectrophotometer (AA) for the elements Fe, Mn, Ti, Pb, Zn, Cu, Cr, Ni, Co, Hg, and Cd (9). The second method utilized a Philips PW 1410 X-ray fluorescence spectrometer for the analysis of elements Fe, Mn, Ti, Ca, K, P, Si, Al, Mg, Na, Pb, Zn, Cu, Cr, V, and Ba (10). The AA analysis was chosen because of the known accuracy and sensitivity to a wide spectrum of elements. The XRF analysis was chosen for its accuracy and similar nondestructive mode of analysis equivalent to the shipboard XRF analysis. Good agreement between the AA and the XRF values was felt to be imperative because the Philips XRF equipment was to be used in the land-based multielement analysis of the CS -collected sediment samples. 

Hutton, R.C. and Preston, B. (1980) A simple non-dispersive atomic-fluorescence spectrometer for mercury determination, using cold-vapour generation. Analyst, 105, 981-984. 

Fig. 20. Scheme of a fluorescence spectrometer for excitation and luminescence spectra, a Light source h monochromator c wavelength advance i beam splitter e quantum coimter /PMT ghigh voltage supply h amplifier i cuvette compartment k ratiometer I recorder. Reprinted from [7] with permission of Springer, Berlin Heidelberg New York. Copyright 1992... 

Wang Yutian, Wang Zhongdong. Study on fluorescence spectrometer for monitoring pesticide residues on vegetables Q]. Journal of Applied Optics, 2005, 26(5) 10-13. (in Chinese with Enghsh abstract)... 

Furthermore, the term ri(Eo) accounts for ionization in all the atomic shells of the ith element where the electron-binding energy is less than the excitation photon energy Eo- Typically it is only the x-rays caused by electron transitions to one of the shells that is monitored in the fluorescence spectrometer. For example, it will be assumed that only the K x-rays of element i are being measured. In this case the number of ionizations of the K shell is reduced to... 

F. S. Goulding and Joseph M. Jaklevic, X-Ray Fluorescence Spectrometer for Airborne Particulate Monitoring, Environmental Protection Technology Series, EPA-R2-73-182, (April 1973), U.S. Environmental Protection Agency, Washington,... 

Although direct densitometry is becoming increasingly important, the spot elution method is still very widely used throughout the world. Many selective and sensitive analyses can be performed in a simple and relatively inexpensive fashion by using TLC for separation and a basic absorption or fluorescence spectrometer for quantification. For example, assay of some drugs by TLC with elution is specified in the United States Pharmacopeia (USP). 

Fluorescence spectrometers for in vivo diagnostics are commonly based on fibre optic systems [30-33], The excitation light of a lamp or a laser is guided to the tissue (e.g. some specific organ) via glass fibre using appropriate optical filters (instead of an excitation monochromator). Fluorescence spectra are usually measured either via the same fibre or via a second fibre or fibre bundle in close proximity to the excitation fibre. Scanning monochromators or OMA systems as reported above are used for emission spectroscopy. 

A widely used procedure for determining trace amounts of selenium involves separating selenium from solution by reduction to elemental selenium using tellurium (as a carrier) and hypophosphorous acid as reductant. The precipitated selenium, together with the carrier, are collected by filtration and the filtered soflds examined directly in the wavelength-dispersive x-ray fluorescence spectrometer (70). Numerous spectrophotometric and other methods have been pubHshed for the deterruination of trace amounts of selenium (71—88). 

When recording excitation and fluorescence spectra it must be ensured that monochromatic light falls on the detector This can best be verified in instruments built up on the kit principle or in those equipped with two monochromators (spectrofluonmeters) The majority of scanners commercially available at the moment do not allow of such an optical train, which was realized in the KM3 chromatogram spectrometer (Zeiss) So such units are not able to generate direct absorption or fluorescence spectra for the charactenzation of fluorescent components... 

Procedures for calibrating both monochromators in a fluorescence spectrometer using narrow line sources have been discussed (IS,18) care must be taken with placement of the calibration source. 

Room-temperature fluorescence (RTF) has been used to determine the emission characteristics of a wide variety of materials relative to the wavelengths of selected Fraunhofer lines in support of the Fraunhofer luminescence detector remote-sensing instrument. RTF techniques are now used in the compilation of excitation-emission-matrix (EEM) fluorescence "signatures" of materials. The spectral data are collected with a Perkin-Elraer MPF-44B Fluorescence Spectrometer interfaced to an Apple 11+ personal computer. EEM fluorescence data can be displayed as 3-D perspective plots, contour plots, or "color-contour" images. The integrated intensity for selected Fraunhofer lines can also be directly extracted from the EEM data rather than being collected with a separate procedure. Fluorescence, chemical, and mineralogical data will be statistically analyzed to determine the probable physical and/or chemical causes of the fluorescence. 

Bronk, H., Rohrs, S., Bjeoumikhov, N., et al. (2001). ArtTAX- a new mobile spectrometer for energy-dispersive micro X-ray fluorescence spectrometry on art and archaeological objects. Fresenius Journal of Analytical Chemistry 371 307-316. 

Figure 1. Flow Cell for Monitoring solvent Permeation and PMMA Film Dissolution Simultaneously. The cell is placed in the sample chamber of a fluorescence spectrometer. (Reproduced with permission from Ref. ll. Copyright 1988 Wiley Sons.)...

The LS-3B is a fluorescence spectrometer with separate scanning monochromators for excitation and emission, and digital displays of both monochromator wavelengths and signal intensity. The LS-5B is a ratioing luminescence spectrometer with the capability of measuring fluorescence, phosphorescence and bio- and chemiluminescence. Delay time (t) and gate width (t) are variable via the keypad in lOps intervals. It corrects excitation and emission spectra. 

Fluorescence spectrometers are equivalent in their performance to singlebeam UV-visible spectrometers in that the spectra they produce are affected by solvent background and the optical characteristics of the instrument. These effects can be overcome by using software built into the Perkin-Elmer LS-5B instrument or by using application software for use with the Perkin-Elmer models 3700 and 7700 computers. 

Figure 5. Schematic diagram of a time-resolved fluorescence spectrometer using a picosecond laser as an excitation source. Inset diagram intensity/time/ wavelength surface for poly (acenaphthalene) in benzene at 20°C. Excitation wavelength 295 nm. (Reproduced with permission from Ref. 21. Copyright 1987 Chemistry in Australia.)...

Figure 12.1 shows the classic L-format of the most commonly used fluorescence spectrometer configuration which is topologically the same for the measurement of both steady-state spectra and lifetimes. The source and detector options of relevance to IR fluorescence measurements are discussed in Sections 12.3 and 12.4, respectively. The other optical components comprised of the lenses for focusing and collection and monochromators for wavelength selection contain few peculiarities in the near-IR as... 

Chromatographic systems have one thing in common most depend on spectro-photometric detection devices, i.e., ultraviolet (UV), visible, fluorescent, and midrange infrared (MIR) spectrometers. High-performance liquid chromatography (HPLC) has been used to, in essence, purify (separate) the constituents from the matrix, then introduce them to a spectrometer for identification or quantification. One reason that spectrometers were not placed in a production setting... 

Introduction into a DC plasma requires rather more care and attention owing to its inherent design features. As the hydride is being introduced into the plasma, it is necessary to provide a controlled sheath of argon to contain the hydride and direct it into the plasma. This chimney effect significantly improves the sensitivity for hydride-forming elements. This interface has also formed the basis of an introduction system for mercury vapour into an atomic-fluorescence spectrometer as described by Godden and Stockwell [12]. 

For low-level mercury measurements, the sensitivity of the fluorescence spectrometer offers the most attractive route for analysis it is also possible to analyse air samples. In the... 

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