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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.
Even though size exclusion chromatography is widely utilized to study natural organic material, there are limitations. One of these limitations include that there is no standard molecular weight marker; [6] thus, there is nothing to compare the results back to. If precise molecular weight is required, other methods should be used.
In chemical analysis, chromatography is a laboratory technique for the separation of a mixture into its components. The mixture is dissolved in a fluid solvent (gas or liquid) called the mobile phase, which carries it through a system (a column, a capillary tube, a plate, or a sheet) on which a material called the stationary phase is fixed ...
Wet chemistry commonly uses laboratory glassware such as beakers and graduated cylinders to prevent materials from being contaminated or interfered with by unintended sources. [3] Gasoline, Bunsen burners , and crucibles may also be used to evaporate and isolate substances in their dry forms.
The date and time, or more often the number of the control run, is plotted on the x-axis. A mark is made indicating how far the actual result was from the mean, which is the expected value for the control. Lines run across the graph at the mean, as well as one, two and three standard deviations to either side of the mean.
An LCR meter is a type of electronic test equipment used to measure the inductance (L), capacitance (C), and resistance (R) of an electronic component. [1] In the simpler versions of this instrument the impedance was measured internally and converted for display to the corresponding capacitance or inductance value.
The carryover ratio is the percentage of H3 carry to L1 constituting the carryover portion "h". In a design of 3 high samples followed by 3 low samples, h can be calculated as (L1 - mean of L2&L3) / (H3 - mean of L2&L3) The carryover ratio's acceptance criteria depend on the measurement and the laboratory concerned.
A simplified method of calculating chromatogram resolution is to use the plate model. [8] The plate model assumes that the column can be divided into a certain number of sections, or plates and the mass balance can be calculated for each individual plate. This approach approximates a typical chromatogram curve as a Gaussian distribution curve ...