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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. Drug reference standard - Wikipedia

    en.wikipedia.org/wiki/Drug_reference_standard

    Pharmacopoeial reference standards are a subset of pharmaceutical reference standards. They are established for the intended use described in pharmacopeial texts (monographs and general chapters). Pharmacopeial reference standards are available from various pharmacopoeias such as United States Pharmacopeia and the European Pharmacopoeia. Where ...

  6. Laboratory quality control - Wikipedia

    en.wikipedia.org/wiki/Laboratory_quality_control

    An example of a Levey–Jennings chart with upper and lower limits of one and two times the standard deviation. A Levey–Jennings chart is a graph that quality control data is plotted on to give a visual indication whether a laboratory test is working well.

  7. List of chemical databases - Wikipedia

    en.wikipedia.org/wiki/List_of_chemical_databases

    ACS Green Chemistry Institute: Solvents Principal components analysis of physical properties curated "Solvent Selection Tool". 272 [11] SPRESI web: InfoChem Gesellschaft für chemische Information mbH organic molecules and reactions organic structures from literature "SPRESI". 5,800,000 SpringerMaterials Springer: solid materials

  8. Elemental analysis - Wikipedia

    en.wikipedia.org/wiki/Elemental_analysis

    Elemental analysis is a process where a sample of some material (e.g., soil, waste or drinking water, bodily fluids, minerals, chemical compounds) is analyzed for its elemental and sometimes isotopic composition.

  9. 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.