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  • bacterial
  • It was found that time-of-flight secondary ion mass spectrometry is a potential tool for differentiating of acellular bacterial from eukaryotic footprints (i.e. extracellular polymeric substance and extracellular matrix produced by the respective cells) and may have potential for the post-hoc diagnosis of colonisation, biofilm formation and implant-related infections even in culture negative cases. (aalto.fi)
  • fragmentation
  • This book discusses fragmentation mechanisms of molecules under mass spectrometry conditions and the resulting peaks observed in ESI-MS/MS experiments. (degruyter.com)
  • Tandem mass spectrometry (MS/MS) is used to measure fragmentation spectra and identify proteins at high speed and accuracy. (wikipedia.org)
  • It is a part of gas phase ion chemistry and there are different types of mass fragmentation: collision-induced dissociation (CID), electron-capture dissociation (ECD), electron-transfer dissociation (ETD), negative electron-transfer dissociation (NETD), electron-detachment dissociation (EDD), photodissociation, particularly infrared multiphoton dissociation (IRMPD) and blackbody infrared radiative dissociation (BIRD), surface-induced dissociation (SID), Higher-energy C-trap dissociation (HCD), charge remote fragmentation. (wikipedia.org)
  • Tandem mass spectrometry, also known as MS/MS or MS2, involves multiple steps of mass spectrometry selection, with some form of fragmentation occurring in between the stages. (wikipedia.org)
  • Now in the 2000's the ambient version of flowing afterglow mass spectrometry is flowing atmospheric pressure afterglow mass spectrometry (FAPA-MS).The FAPA allows for simple or no sample preparations but the humidity of the instrument's environment may have an effect on an sample fragmentation pattern.Since the cost of helium is steady rising some have started to use alternative methods with ambient flowing afterglow to conserve resources. (wikipedia.org)
  • spectrometers
  • In addition to the three mass spectrometers described below, there are areas for data processing, instrument maintenance, parts storage and sample preparation. (umsl.edu)
  • Isotope analyses using mass spectrometers have been frequently utilized in the laboratories for the earth planetary science and other scientific and industrial fields. (go.jp)
  • In order to conduct in-situ measurements of compositions and isotope ratios around planets and moons, mass spectrometers onboard spacecraft have also been developed. (go.jp)
  • Ion and electron instruments on orbiters have provided much outputs for the space and planetary science since the early days and mass spectrometers on landers and rovers have recently performed isotope analyses on planetary bodies. (go.jp)
  • We review spaceborne mass spectrometers, instrumentations, and observation results. (go.jp)
  • Starting with spaceborne ion instruments to measure three distribution functions as well as mass for the space plasma physics, mass spectrometers have evolved to recent high-mass-resolution instruments for solar system exploration missions. (go.jp)
  • The much reduced complexity of purified samples allow the use of shorter gradient times and does not require the use advanced mass spectrometers. (sun.ac.za)
  • Sector mass spectrometers known as calutrons were developed by Ernest O. Lawrence and used for separating the isotopes of uranium during the Manhattan Project. (wikipedia.org)
  • Calutron mass spectrometers were used for uranium enrichment at the Oak Ridge, Tennessee Y-12 plant established during World War II. (wikipedia.org)
  • Over the years, different manufacturers of mass spectrometers have developed various proprietary data formats for handling such data which makes it difficult for academic scientists to directly manipulate their data. (wikipedia.org)
  • Mass spectrometers were used in the Manhattan Project for the separation of isotopes of uranium necessary to create the atomic bomb. (wikipedia.org)
  • However, they can normally incorporate commercial mass spectrometers. (wikipedia.org)
  • peptides
  • Mass analysis of proteolytic peptides is a popular method of protein characterization, as cheaper instrument designs can be used for characterization. (wikipedia.org)
  • differs
  • Mass spectrometry differs from the types of spectroscopy previously discussed because the molecular information that the technique provides does not depend on absorption of electromagnetic radiation. (britannica.com)
  • This differs from the definition of mass defect used in physics which is the difference between the mass of a composite particle and the sum of the masses of its constituent parts. (wikipedia.org)
  • spectrograph
  • English scientist J.J. Thomson later improved on the work of Wien by reducing the pressure to create a mass spectrograph. (newworldencyclopedia.org)
  • The use of electromagnetic focusing in mass spectrograph which rapidly allowed him to identify no fewer than 212 of the 287 naturally occurring isotopes. (wikipedia.org)
  • spectrometric
  • The Mass Spectrometry Unit, part of the Central Analytical Facilities of Stellenbosch University, serves as a resource offering contemporary mass spectrometric techniques and the 'state-of-the-art' instrumen-tation needed for the diversity of research interests on- and off-campus. (sun.ac.za)
  • This permits compounds to be assigned to the Δ 4 or Δ 5 series on the basis of mass-spectrometric data. (springer.com)
  • analyzer
  • For a precursor ion scan, the product ion is selected in the second mass analyzer, and the precursor masses are scanned in the first mass analyzer. (wikipedia.org)
  • In a product ion scan, a precursor ion is selected in the first stage, allowed to fragment and then all resultant masses are scanned in the second mass analyzer and detected in the detector that is positioned after the second mass analyzer. (wikipedia.org)
  • This experiment is commonly performed to identify transitions used for quantification by tandem MS. In a neutral loss scan, the first mass analyzer scans all the masses. (wikipedia.org)
  • The second mass analyzer also scans, but at a set offset from the first mass analyzer. (wikipedia.org)
  • It took advantage of a time-of-flight mass analyzer. (wikipedia.org)
  • ratio
  • Wilhelm Wien found that strong electric or magnetic fields deflected the canal rays and, in 1899, constructed a device with parallel electric and magnetic fields that separated the positive rays according to their charge-to-mass ratio (Q/m) . (newworldencyclopedia.org)
  • Wien found that the charge-to-mass ratio depended on the nature of the gas in the discharge tube. (newworldencyclopedia.org)
  • The instrument did yield unit resolution up to a mass-to-charge ratio of 115. (wikipedia.org)
  • separation
  • The IUPAC definition for resolution in mass spectrometry is R = M Δ M {\displaystyle R={\cfrac {M}{\Delta M}}} = resolution Δ M {\displaystyle \Delta M} = resolving power M {\displaystyle M} = mass of the (second) peak Where a larger resolution indicates a better separation of peaks. (wikipedia.org)
  • High resolution indicating better peak separation is also used in ion mobility spectrometry Some mass spectrometrists use the definition that is similar to definitions used in some other fields of physics and chemistry. (wikipedia.org)
  • There are several ways to define the minimum peak separation ΔM in mass spectrometry, therefore it is important to report the method used to determine mass resolution when reporting its value. (wikipedia.org)
  • In tandem mass spectrometry in space, the separation elements are physically separated and distinct, although there is a physical connection between the elements to maintain high vacuum. (wikipedia.org)
  • Converters
  • FileConverter: A command line tool that converts to/from various mass spectrometry formats, part of TOPP Converters for proprietary formats: msConvert: A command line tool converting to/from various mass spectrometry formats including multiple proprietary formats. (wikipedia.org)
  • refers
  • When an exact mass value is given without specifying an isotopic species, it normally refers to the most abundant isotopic species. (wikipedia.org)
  • This refers to the mass of the molecule with the most highly represented isotope distribution, based on the natural abundance of the isotopes. (wikipedia.org)
  • sensitivity
  • Using this technique has resulted in an increase of sensitivity for larger mass samples. (wikipedia.org)
  • NanoSIMS is able to create nanoscale maps of elemental composition, parallel acquisition of seven masses, isotopic identification , combining the high mass resolution, subparts-per-million sensitivity of conventional SIMS with spatial resolution down to 50 nm and fast acquisition (DC mode, not pulsed). (wikipedia.org)
  • isotope
  • The ion of mass 22 was, in fact, a stable heavy isotope of neon. (britannica.com)
  • In order to achieve precise isotope measurements, there is a need for high transmission and high mass resolution . (wikipedia.org)
  • So, when you do mass spectrometry, you get two signals of different intensities depending on the natural abundance of each isotope. (physicsforums.com)
  • from this observation they immediately and correctly concluded that the other mass-3 isotope tritium was radioactive. (wikipedia.org)
  • The mass number is unique for each isotope of an element and is written either after the element name or as a superscript to the left of an element's symbol. (wikipedia.org)
  • The nominal mass for an element is the mass number of its most abundant naturally occurring stable isotope, and for an ion or molecule, the nominal mass is the sum of the nominal masses of the constituent atoms. (wikipedia.org)
  • Isotope abundances are tabulated by IUPAC: for example carbon has two stable isotopes 12C at 98.9% natural abundance and 13C at 1.1% natural abundance, thus the nominal mass of carbon is 12. (wikipedia.org)
  • The monoisotopic mass is the sum of the masses of the atoms in a molecule using the unbound, ground-state, rest mass of the principal (most abundant) isotope for each element. (wikipedia.org)
  • His work on isotopes also led to his formulation of the Whole Number Rule which states that "the mass of the oxygen isotope being defined [as all the other isotopes have masses that are very nearly whole numbers," a rule that was used extensively in the development of nuclear energy. (wikipedia.org)
  • isotopes
  • Mass spectroscopes also are employed to separate isotopes and to measure the abundance of concentrated isotopes when used as tracers in chemistry , biology, and medicine . (britannica.com)
  • The exact mass of an isotopic species (more appropriately, the calculated exact mass) is obtained by summing the masses of the individual isotopes of the molecule. (wikipedia.org)
  • The monoisotopic mass of a molecule or ion is the exact mass obtained using the principal isotopes. (wikipedia.org)
  • The first such discovery was with the element neon, which was shown by mass spectrometry to have at least two stable isotopes: 20Ne (neon with 10 protons and 10 neutrons) and 22Ne (neon with 10 protons and 12 neutrons). (wikipedia.org)
  • The exact mass of many isotopes was measured leading to the result that hydrogen has a 1% higher mass than expected by the average mass of the other elements. (wikipedia.org)
  • molecular mass
  • The molecular mass (abbreviated Mr) of a substance, formerly also called molecular weight and abbreviated as MW, is the mass of one molecule of that substance, relative to the unified atomic mass unit u (equal to 1/12 the mass of one atom of 12C). (wikipedia.org)
  • Due to this relativity, the molecular mass of a substance is commonly referred to as the relative molecular mass, and abbreviated to Mr. The average mass of a molecule is obtained by summing the average atomic masses of the constituent elements. (wikipedia.org)
  • analyzers
  • When using multiple quadrupoles, they can act as both mass analyzers and collision chambers. (wikipedia.org)
  • To obtain this information, both mass analyzers are scanned simultaneously, but with a mass offset that correlates with the mass of the specified neutral. (wikipedia.org)
  • In selected reaction monitoring, both mass analyzers are set to a selected mass. (wikipedia.org)
  • As a concept in analytical chemistry TRMS encompasses instrumental developments (e.g. interfaces, ion sources, mass analyzers), methodological developments, and applications. (wikipedia.org)
  • measurements
  • The term mass spectroscope continued to be used even though the direct illumination of a phosphor screen was replaced by indirect measurements with an oscilloscope. (newworldencyclopedia.org)