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A mass spectrum is a histogram plot of intensity vs. mass-to-charge ratio (m/z) in a chemical sample, [1] usually acquired using an instrument called a mass spectrometer. Not all mass spectra of a given substance are the same; for example, some mass spectrometers break the analyte molecules into fragments ; others observe the intact molecular ...
Mass spectral interpretation is the method employed to identify the chemical formula, characteristic fragment patterns and possible fragment ions from the mass spectra. [1] [2] Mass spectra is a plot of relative abundance against mass-to-charge ratio. It is commonly used for the identification of organic compounds from electron ionization mass ...
The mass defect used in nuclear physics is different from its use in mass spectrometry. In nuclear physics, the mass defect is the difference in the mass of a composite particle and the sum of the masses of its component parts. In mass spectrometry the mass defect is defined as the difference between the exact mass and the nearest integer mass.
Ion mobility spectrometry-mass spectrometry (IMS/MS or IMMS) is a technique where ions are first separated by drift time through some neutral gas under an applied electrical potential gradient before being introduced into a mass spectrometer. [43] Drift time is a measure of the collisional cross section relative to the charge of the ion.
In mass spectrometry, resolution is a measure of the ability to distinguish two peaks of slightly different mass-to-charge ratios ΔM, in a mass spectrum. Resolution and resolving power [ edit ]
Nominal mass is a term used in high level mass spectrometric discussions, it can be calculated using the mass number of the most abundant isotope of each atom, without regard for the mass defect. For example, when calculating the nominal mass of a molecule of nitrogen (N 2) and ethylene (C 2 H 4) it comes out as. N 2 (2*14)= 28 Da C 2 H 4
Laser ionization time-of-flight mass spectrometer where ions are accelerated and separated by mass in a field-free drift region before detection Bendix MA-2 Time-of-Flight Mass Spectrometer, 1960s. Time-of-flight mass spectrometry (TOFMS) is a method of mass spectrometry in which an ion's mass-to-charge ratio is determined by a time of flight ...
When charged particles move in electric and magnetic fields the following two laws apply: Lorentz force law: = (+),; Newton's second law of motion: = =; where F is the force applied to the ion, m is the mass of the particle, a is the acceleration, Q is the electric charge, E is the electric field, and v × B is the cross product of the ion's velocity and the magnetic flux density.