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  • spectrometric
  • e _e __ M-A-S-S S-P-GBP-C-T-R-O-M-GBP-T-R-Y in Morse code This volume collects descriptions of selected recent developments in state-of- the-art mass spectrometric methods and reflects the broad-based approaches that mass spectroscopists apply to a variety of important clinical and bio- medical problems. (booktopia.com.au)
  • Dissociation
  • Factors affecting fragmentation are the charge state (the higher charge state, the less energy is needed for fragmentation), mass of the peptide (the larger mass, the more energy is required), induced energy (higher energy leads to more fragmentation), primary amino acid sequence, mode of dissociation and collision gas. (wikipedia.org)
  • ionization method
  • 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. (wikipedia.org)
  • 10,000
  • In FAB and LSIMS, the material to be analyzed is mixed with a non-volatile chemical protection environment, called a matrix, and is bombarded under vacuum with a high energy (4000 to 10,000 electron volts) beam of atoms. (wikipedia.org)
  • sequence
  • Carbohydrate sequence and branching information, and fatty acid and lipid base composition were readily obtained from the mass spectra of glycosphingolipids while bidirectional nucleotide sequence, nucleotide base, and protecting group assignments were obtained for oligonucleotides. (illinois.edu)
  • In mass spectrometry, de novo peptide sequencing is the method in which a peptide amino acid sequence is determined from tandem mass spectrometry. (wikipedia.org)
  • Database search is a simple version as the mass spectra data of the unknown peptide is submitted and run to find a match with a known peptide sequence, the peptide with the highest matching score will be selected. (wikipedia.org)
  • analysis
  • Fast atom bombardment was found to be one-to-two orders of magnitude more sensitive than field desorption based on the analysis of a limited number of compounds from several classes. (illinois.edu)
  • Suitable negative ion mass markers were found in dispersions of poly(ethylene) and poly(propylene) glycols in a triethylenetetramine matrix, a matrix which also proved useful in the analysis of glycosphingolipids. (illinois.edu)
  • Classical quantitative analysis uses mass or volume changes to quantify amount. (wikipedia.org)
  • The first instrumental analysis was flame emissive spectrometry developed by Robert Bunsen and Gustav Kirchhoff who discovered rubidium (Rb) and caesium (Cs) in 1860. (wikipedia.org)
  • measurement
  • Negative ion mass markers, necessary for accurate mass measurements of the aforementioned classes of compounds and in newly proposed scanning accurate mass measurement methods, were also developed. (illinois.edu)
  • molecular
  • Penning ionization involves a reaction between a gas-phase excited-state atom or molecule G* and a target molecule M resulting in the formation of a radical molecular cation M+. (wikipedia.org)
  • neutral
  • Charge-exchange ionization (also known as charge-transfer ionization) is a gas phase reaction between an ion and an atom or molecule in which the charge of the ion is transferred to the neutral species. (wikipedia.org)
  • heavy atoms
  • Because the observed effects for isotopic substitution of heavy atoms are extremely small, typically a few percent, they cannot be determined by direct comparison of experimentally determined rate constants. (pubmedcentralcanada.ca)
  • Since ISC is promoted by large spin-orbit coupling, the incorporation of heavy atoms such as iodine or bromine, precious metals such as iridium or platinum, or arylcarbonyl groups into luminophores effectively accelerates ISC and efficiently generates T 1 . (rsc.org)
  • electron
  • High-energy hydrogen (deuterium) atoms are obtained during the excitation of the hydrogen subsystem by electron irradiation due to the generation of plasma oscillations (plasmons) in a crystal lattice or hydrogen subsystem [ 9 , 10 ]. (mdpi.com)
  • Carbon-silicon (C-Si) polymeric films have been formed by electron beam bombardment or ultraviolet (UV) radiation of molecularly adsorbed vinyl silane precursors on metal substrates under ultra-high vacuum (UHV) conditions. (unt.edu)
  • A fast proton moving through matter will slow by interactions with electrons and nuclei, until it is captured by the electron cloud of an atom. (wikipedia.org)
  • In vacuum, when free electrons are present, a sufficiently slow proton may pick up a single free electron, becoming a neutral hydrogen atom, which is chemically a free radical. (wikipedia.org)
  • In FAB and LSIMS, the material to be analyzed is mixed with a non-volatile chemical protection environment, called a matrix, and is bombarded under vacuum with a high energy (4000 to 10,000 electron volts) beam of atoms. (wikipedia.org)
  • electrons
  • Every atom is composed of a nucleus and one or more electrons bound to the nucleus. (wikipedia.org)
  • The number of electrons influences the magnetic properties of an atom. (wikipedia.org)
  • However, since particles from different gases had different values of charge-to-mass ratio (e/m), they could not be identified with a single particle, unlike the negative electrons discovered by J. J. Thomson. (wikipedia.org)
  • But, every so often, a few of them steal electrons from neutral atoms they run into. (wikipedia.org)
  • In a charge-exchange collision between a high energy plasma ion and a cold neutral atom, the ion 'steals' electrons from the neutral atom, producing a cold ion and an energetic neutral atom(ENA). (wikipedia.org)
  • I1+ + A2 → A1 + I2+ where I1+ plasma ion A2 background neutral atom (lower energy) A1 energetic neutral atom (ENA) I2+ lower energy ion Species 1 and 2 may be the same or different and an exchange of two electrons is possible, e.g. (wikipedia.org)
  • Antigravity - Antimatter - Antineutron - Antiparticle - Antiproton - Arc length - Archimedes' principle - Area moment of inertia - Astronomical unit - Astrophysics - The branch of astronomy that deals with the physics of the universe, especially with "the nature of the heavenly bodies, rather than their positions or motions in space Attenuation coefficient - Atom - A basic unit of matter that consists of a dense central nucleus surrounded by a cloud of negatively charged electrons. (wikipedia.org)
  • beam
  • Elastic Recoil Detection Analysis (ERDA), also referred to as forward recoil scattering (or, contextually, spectrometry), is an Ion Beam Analysis technique in materials science to obtain elemental concentration depth profiles in thin films. (wikipedia.org)
  • The energy of the beam should be enough to kick out ("recoil") the atoms of the sample. (wikipedia.org)
  • react
  • In the early 1800s, John Dalton used the concept of atoms to explain why elements always react in ratios of small whole numbers (the law of multiple proportions). (wikipedia.org)
  • This common pattern in chemistry suggested to Dalton that elements react in whole number multiples of discrete units-in other words, atoms. (wikipedia.org)
  • Such "free hydrogen atoms" tend to react chemically with many other types of atoms at sufficiently low energies. (wikipedia.org)
  • spectrometer
  • He remained at Oxford for his PhD, which involved the design of a mass spectrometer under the supervision of John Wilfrid Linnett. (wikipedia.org)
  • A mass spectrometer consists of three components: an ion source, a mass analyzer, and a detector. (wikipedia.org)
  • Cotter was also a co-investigator on the Mars Organic Molecule Analyzer (MOMA) project, developing a miniaturized, low power consumption ion trap/time-of-flight mass spectrometer that was to be deployed with the ExoMars rover. (wikipedia.org)
  • Cotter was a deputy principal investigator and responsible for the design and development of a low-power, ion trap-time-of-flight mass spectrometer to be deployed with the ESA ExoMars rover. (wikipedia.org)
  • In continuous flow fast atom bombardment (CF-FAB), the sample is introduced into the mass spectrometer insertion probe through a small diameter capillary. (wikipedia.org)
  • consists
  • Neon in the upper atmosphere only consists of 20 parts per million by mass, which is about a tenth as abundant as in the Sun. Helium is also depleted to about 80% of the Sun's helium composition. (wikipedia.org)
  • Chemically, about three quarters of the Sun's mass consists of hydrogen, while the rest is mostly helium. (wikipedia.org)
  • The remaining 1.69% (equal to 5,600 times the mass of Earth) consists of heavier elements, including oxygen, carbon, neon and iron. (wikipedia.org)
  • particles
  • The physicist J. J. Thomson measured the mass of cathode rays, showing they were made of particles, but were around 1800 times lighter than the lightest atom, hydrogen. (wikipedia.org)
  • energies
  • In 1993, Cotter's research group discovered that, using a non-linear electric field, the spread of ion kinetic energies could be compensated, increasing the resolution of time-of-flight mass spectrometers and forming the basis for many modern TOF/TOF mass spectrometers. (wikipedia.org)
  • tend
  • Xe atoms are used because they tend to be more sensitive than Argon atoms due to their larger masses and more momentum. (wikipedia.org)
  • experimentally
  • French physicist Jean Perrin used Einstein's work to experimentally determine the mass and dimensions of atoms, thereby conclusively verifying Dalton's atomic theory. (wikipedia.org)
  • molecular mass
  • The central mucin domain is dominated by proline-, serine- and threonine-rich repetitive and non-repetitive sequences that undergo O-glycosylation and account for up to 80% of the mucin molecular mass [ 2 , 9 ]. (biochemsoctrans.org)
  • magnetic
  • Wilhelm Wien found that strong electric or magnetic fields deflected the canal rays and, in 1899, constructed a device with perpendicular electric and magnetic fields that separated the positive rays according to their charge-to-mass ratio (Q/m). (wikipedia.org)
  • These phenomena are generated by a helical dynamo near the center of the Sun's mass that generates strong magnetic fields and a chaotic dynamo near the surface that generates smaller magnetic field fluctuations. (wikipedia.org)
  • Solar System
  • It is a giant planet with a mass one-thousandth that of the Sun, but two-and-a-half times that of all the other planets in the Solar System combined. (wikipedia.org)
  • It has a diameter of about 1,392,684 kilometres (865,374 mi), around 109 times that of Earth, and its mass (1.989×1030 kilograms, approximately 330,000 times that of Earth) accounts for some 99.86% of the total mass of the Solar System. (wikipedia.org)
  • masses
  • Regularly these systems include a few planets with masses several times greater than Earth's (super-Earths), orbiting closer to their star than Mercury is to the Sun, and sometimes also Jupiter-mass gas giants close to their star. (wikipedia.org)
  • The rest masses of quarks contribute only about 1% of a proton's mass, however. (wikipedia.org)
  • In simpler terms, a mass spectrum measures the masses within a sample. (wikipedia.org)
  • dense
  • The central mass became increasingly hot and dense, eventually initiating thermonuclear fusion in its core. (wikipedia.org)
  • different
  • Cubic zirconia belongs to a family of zirconia minerals, each having a different configuration of atoms that give rise to different crystal lattice structures, called polymorphs. (geologyin.com)
  • Every time the atoms shift to transform into a different polymorph, they leave evidence behind within the crystal. (geologyin.com)
  • Quickly after the lunar crust formed, or even as it was forming, different types of magmas that would give rise to the Mg-suite norites and troctolites began to form, although the exact depths at which this occurred are not known precisely. (wikipedia.org)
  • known
  • 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)
  • small
  • Atoms are small enough that attempting to predict their behavior using classical physics - as if they were billiard balls, for example - gives noticeably incorrect predictions due to quantum effects. (wikipedia.org)
  • chemistry
  • The ability of atoms to associate and dissociate is responsible for most of the physical changes observed in nature and is the subject of the discipline of chemistry. (wikipedia.org)
  • It was not until the 19th century that the idea was embraced and refined by scientists, when the blossoming science of chemistry produced discoveries that only the concept of atoms could explain. (wikipedia.org)