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  2. Certified reference materials - Wikipedia

    en.wikipedia.org/wiki/Certified_reference_materials

    A certified reference material is a particular form of measurement standard. Reference materials are particularly important for analytical chemistry and clinical analysis. [2] Since most analytical instrumentation is comparative, it requires a sample of known composition (reference material) for accurate calibration.

  3. Reference materials for stable isotope analysis - Wikipedia

    en.wikipedia.org/wiki/Reference_materials_for...

    The δ values and absolute isotope ratios of common reference materials are summarized in Table 1 and described in more detail below. Alternative values for the absolute isotopic ratios of reference materials, differing only modestly from those in Table 1, are presented in Table 2.5 of Sharp (2007) [1] (a text freely available online), as well as Table 1 of the 1993 IAEA report on isotopic ...

  4. Primary standard - Wikipedia

    en.wikipedia.org/wiki/Primary_standard

    A primary standard in metrology is a standard that is sufficiently accurate such that it is not calibrated by or subordinate to other standards. Primary standards are defined via other quantities like length, mass and time. Primary standards are used to calibrate other standards referred to as working standards. [1] [2] See Hierarchy of Standards.

  5. Laboratory quality control - Wikipedia

    en.wikipedia.org/wiki/Laboratory_quality_control

    Quality control material should approximate the same matrix as patient specimens, taking into account properties such as viscosity, turbidity, composition, and color. IIt should be stable for long periods of time, and available in large enough quantities for a single batch to last at least one year.

  6. Drug reference standard - Wikipedia

    en.wikipedia.org/wiki/Drug_reference_standard

    A drug reference standard or pharmaceutical reference standard is a highly characterized material suitable to test the identity, strength, quality and purity of substances for pharmaceutical use and medicinal products.

  7. Reference electrode - Wikipedia

    en.wikipedia.org/wiki/Reference_electrode

    A reference electrode is an electrode that has a stable and well-known electrode potential. The overall chemical reaction taking place in a cell is made up of two independent half-reactions , which describe chemical changes at the two electrodes.

  8. Dad Allegedly ‘Stole Money' from His Spouse and Kids to ...

    www.aol.com/dad-allegedly-stole-money-spouse...

    A New Jersey family is suing DraftKings after a father of two gambled away more than $1 million of his family’s money across four years. The man, known by his username Mdallo1990, allegedly lost ...

  9. Gravimetric analysis - Wikipedia

    en.wikipedia.org/wiki/Gravimetric_analysis

    Gravimetric analysis describes a set of methods used in analytical chemistry for the quantitative determination of an analyte (the ion being analyzed) based on its mass. The principle of this type of analysis is that once an ion's mass has been determined as a unique compound, that known measurement can then be used to determine the same analyte's mass in a mixture, as long as the relative ...