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  2. Sample size determination - Wikipedia

    en.wikipedia.org/wiki/Sample_size_determination

    The sample size is an important feature of any empirical study in which the goal is to make inferences about a population from a sample. In practice, the sample size used in a study is usually determined based on the cost, time, or convenience of collecting the data, and the need for it to offer sufficient statistical power .

  3. Liquid chromatography–mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Liquid_chromatography...

    The ion source converts and fragments the neutral sample molecules into gas-phase ions that are sent to the mass analyzer. While the mass analyzer applies the electric and magnetic fields to sort the ions by their masses, the detector measures and amplifies the ion current to calculate the abundances of each mass-resolved ion.

  4. Analytical quality control - Wikipedia

    en.wikipedia.org/wiki/Analytical_quality_control

    Both tests should accurately measure the purity of the sample. Quantitative tests of either the active moiety or other components of a sample can be conducted through assay procedures. Other analytical procedures such as dissolution testing or particle size determination may also need to be validated and are equally important.

  5. Sample preparation in mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Sample_preparation_in_mass...

    Sample preparation for mass spectrometry is used for the optimization of a sample for analysis in a mass spectrometer (MS). Each ionization method has certain factors that must be considered for that method to be successful, such as volume, concentration, sample phase, and composition of the analyte solution. Quite possibly the most important ...

  6. Chromatography - Wikipedia

    en.wikipedia.org/wiki/Chromatography

    When the sample is treated in the course of an analysis, the phase or the phases containing the analytes of interest is/are referred to as the sample whereas everything out of interest separated from the sample before or in the course of the analysis is referred to as waste. Solute – the sample components in partition chromatography.

  7. Standard addition - Wikipedia

    en.wikipedia.org/wiki/Standard_addition

    When working with limiting amount of sample, an analyst might need to make a single addition, but it is generally considered a best practice to make at least two additions whenever possible. [5] Note that this is not limited to liquid samples. In atomic absorption spectroscopy, for example, standard additions are often used with solid as the ...

  8. Size-exclusion chromatography - Wikipedia

    en.wikipedia.org/wiki/Size-exclusion_chromatography

    There is also no sample loss because solutes do not interact with the stationary phase. The other advantage to this experimental method is that in certain cases, it is feasible to determine the approximate molecular weight of a compound. The shape and size of the compound (eluent) determine how the compound interacts with the gel (stationary ...

  9. Internal standard - Wikipedia

    en.wikipedia.org/wiki/Internal_standard

    In the calibration curve that uses the internal standard, the y-axis is the ratio of the nickel signal to the yttrium signal. This ratio is unaffected by uncertainty in the nickel measurements, as it should affect the yttrium measurements in the same way. This results in a higher R 2, 0.9993.