Calibration chemical databases

The revised database holds over 23 000 analyte values for 660 measurands and 1670 reference materials produced by 56 different producers, from 22 countries. The database is restricted to natural matrix materials (i.e. made from naturally occurring materials, excluding calibration standards manufactured from pure chemicals). Information has been extracted from the relevant certificates of analysis, information sheets, and other reports provided by the reference material producers. As a general rule, the authors have only included in the compilation reference materials for which a certificate of analysis or similar documentation is on file. Information included in the survey is on values for measurands determined in reference materials, producers, suppliers, the cost of the materials, the unit size supplied, and the recommended minimum weight of material for analysis, if available. The new searchable database has been designed to help analysts to select reference materials for quality assurance purposes that match as closely as possible, with respect to matrix type and concentrations of the measurands of interest and their samples to be analyzed see Table 8.3. 

Each data point must be transferred from data sheets into spreadsheets or databases. Verification of each datum should be performed by an individual who did not enter the data being verified. Audits of each phase of the study should be performed (i.e. preparation of collection forms, application calibration, each type of sample collection, sample transport, each type of chemical analysis, data recording, data entry, data verification and data storage). 

The EUSAAR project of the Sixth Framework Programme of the European Commission is one of the steps towards a reliable and quality-controlled network of measurements [16]. The EUSAAR project improved and homogenized 20 European sites for measuring aerosol chemical, physical, and optical properties following a standardized protocol of instrument maintenance, measurement procedures, and data delivery in common format to a common database. EUSAAR also provided intercomparison and calibration workshops as well as training for the station operators. The work started in the EUSAAR is continued in ACTRIS infrastructure of the Seventh Framework Programme of the European Commission. 

An important task of the network is also to ensure that the national references are firmly linked up with the international reference framework for chemical measurements, represented by the results of the CCQM key comparisons listed in the BIPM key comparison database (KCDB). For this purpose, every network member takes part in CCQM key comparisons on its own responsibility and submits its own calibration and measurement capabilities (CMC) to the international evaluation procedure for entry into the KCDB. The key comparisons and the CMCs form the technical basis of the CIPM-MRA. 

The principal output of this MRA is a key comparison database (KCDB) at the Bureau International des Poids et Mesures (www.bipm.org/kcdb) containing the results of international comparisons of national measurement standards and capabilities, known as key comparisons, which underpin and extensive lists of the calibration and measurement capabilities (CMCs) of NMIs. The CMCs of NMIs for chemical measurements are included in the KCDB, and listed under Amount of Substance. The chemical categories covered are high-purity chemicals, inorganic... 

Two basic methods have been utilized for drying forage samples oven and microwave. The two methods produce spectra with somewhat different characteristics and thus it is the preferred procedure to use only one drying method for any calibration database. The oven-drying procedure producing the minimum chemical changes in the sample involves a forced air conveetion oven at 65 C. Samples are left in the oven until they attain approximately 95% dry matter (8 to 12 h). 

As described in this chapter, Raman spectroscopy can provide unique information regarding the molecular composition of tissues and the changes therein caused by disease or chemical/pharmaceutical challenges. It is also clear that there exist no serious technological obstacles for the in vivo application of the technique, which means that the investigation of many potential clinical applications is within reach. The fact that for many of these applications it will prove necessary to establish extensive databases of tissue spectra, which represent all the spectral variance that can be encountered in practice, calls for rigorous standardization with respect to experimental conditions and instrument calibrations. It should be possible to construct databases on one or a few instruments that will form the... 

Fig. 18 The new strategy outlined in Fig. 17 was evaluated in the analysis of protein-affinity pull-down experiments, to distinguish specifically enriched sample components from experimental artifacts. The carboxy terminus of Hsp70-interacting protein (CHIP) was expressed as GST fusion protein in E. coli and used as bait to affinity purify potential interaction partners from a crude human brain protein extract, a Peptide profile obtained from the LC-MALDl MS analysis of the protein isolate obtained from the affinity pull-down experiment. Blue dots-, unpaired peptides, red dots paired signals, black dots all detected monoisotopic peaks, b Mass spectrum acquired from fraction 89. The signal of m/z 1253.62 is, apart from the internal calibrants, the only unpaired signal in the spectrum, indicating that it originates from a protein that specifically interacts with CHIP, c MS/MS spectrum of m/z 1253.62. A database search identified the peptide FEEL-NADLFR of heat shock cognate 71-kDa protein. Reproduced from [316] with permission from American Chemical Society, 2006...

SRD 71 [68] and SRD 82 [41], provide convenient data for IMFPs, EALs, and MEDs. Other NIST databases and software from various sources provide simulations of spectra for thin-film samples [95], reference data needed for modeling the transport of signal electrons in different materials [35], chemical-state information [96], instrumental calibration [118], identification of sample morphology [124], and spectrum-analysis tools. 

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