Emission standards biological

Tin plate, thickness of tin coating on, determination by x-ray spectrography, 148, 149, 157, 158 Tissues, determination of dry weight by absorptiometry, 297-300 Tissue sections, biological, determination of mineral elements in, 301-305 Titanium, as internal standard in vanadium determination, 188 determination by x-ray emission spectrography, 222, 329 trace analysis by x-ray emission spectrography, 163, 225-229 Topaz, as analyzing crystal, 116-118, 220, 318-327 Total reflection, 112, 117... 

Proteases are one of the largest families of enzymes and are involved in a multitude of vital processes. Due to their biological relevance and diversity, multiple fluorescent reporters monitoring their activity have been designed and successfully applied in vitro and in vivo [112-114]. Standard small molecule FRET probes for proteases consist of an amino acid sequence flanked by a FRET pair, consisting of two fluorophores or one fluorophore and a quencher molecule. Upon cleavage of the peptide sequence, the emission of the donor fluorophore is dequenched and the intensity increases whereas the emission of the acceptor decreases and vanishes more or less completely in those cases where the acceptor is fluorescent (see Fig. 6.11). 

The nomenclature of nickel compounds should be further standardized (WHO 1991). Analytical methods must be developed and standardized in order to facilitate speciation of nickel compounds in atmospheric emissions, biological materials, and in other environmental samples (NAS 1975 WHO 1991). Studies are needed to elucidate the biogeochemical nickel cycle on a global scale and determine its potential for long-range transport (WHO 1991). 

Nickel is normally present at very low levels in biological samples. To determine trace nickel levels in these samples accurately, sensitive and selective methods are required. Atomic absorption spectrometry (AAS) and inductively coupled plasma-atomic emission spectroscopy (ICP-AES), with or without preconcentration or separation steps, are the most common methods. These methods have been adopted in standard procedures by EPA, NIOSH, lARC, and the International Union of Pure and Applied... 

The certification procedure for seven trace metals (Ba, Ca, Li, Mg, Mn, Na and Sr) in the certified reference material FEBS-1 (National Research Council Canada, Institute for National Measurement Standards, Ottawa, Canada) based on fish otolith matrix by isotope dilution - ICP-MS in comparison to ICP optical emission spectrometry and X-ray fluorescence analysis, is described by Sturgeon et al4X The isotope dilution technique is also employed for species analysis in biological systems,46 e.g., for the determination of mercury species in tuna material,54 or in aquatic systems using cold vapour ICP-MS.55... 

Chemical and biological evaluation of building material emissions. II. Approaches for setting indoor air standards or guidelines for chemicals. Indoor Air, 7, 17-32. 

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