Where results make sense

About us   |   Why use us?   |   Reviews   |   PR   |   Contact us

Mass Spectrometer Mass spectrometers are sensitive detectors of isotopes based on their masses. For example, the SOHO satellite uses a mass spectrometer to analyze the solar wind. Mass spectrometers are used for the analysis of residual gases in high vacuum systems. hyperphysics.phy-astr.gsu.edu /hbase/magnetic/maspec.html   (298 words)

ASMS:: Education - What is Mass Spectrometry? A mass spectrometer is an instrument that measures the masses of indiviual molecules that have been converted into ions, i.e., molecules that have been electrically charged. Mass spectrometrists often speak loosely of the "mass of an ion" when they really mean the m/z ratio, but this convenient way of speaking is useful only for the case of singly-charged ions. Early mass spectrometers required a sample to be a gas, but due to modern developments decribed below, the applicability of mass spectrometry has been extended to include samples in liquid solutions or embedded in a solid matrix. www.asms.org /whatisms/p4.html   (514 words)

Mass Spectrometry A mass spectrum will usually be presented as a vertical bar graph, in which each bar represents an ion having a specific mass-to-charge ratio (m/z) and the length of the bar indicates the relative abundance of the ion. The unit mass resolution is readily apparent in these spectra (note the separation of ions having m/z=39, 40, 41 and 42 in the cyclopropane spectrum). The mass calculator on the right may be used to calculate the exact mass of a molecule based on its elemental composition. www.cem.msu.edu /~reusch/VirtualText/Spectrpy/MassSpec/masspec1.htm   (2839 words)

Gas chromatograph/mass spectrometer - Patent 5837883   (Site not responding. Last check: 2007-10-03) A shield is disposed between a gas chromatograph unit and a mass spectrometer unit and, further, the space between the gas chromatograph unit and the space the shield and the mass spectrometer unit are ventilated by a ventilating fan or ventilating fans. The gas chromatograph/mass spectrometer according to claim 1, wherein the ventilating means comprises a ventilating fan for ventilating both of the space between the gas chromatograph unit and the shield and the space between the mass spectrometer and the shield. The gas chromatograph/mass spectrometer according to claim 2, wherein the ventilating means comprises a ventilating fan for ventilating both of the spaces between the gas chromatograph unit and the shield and the space between the mass spectrometer and the shield. www.freepatentsonline.com /5837883.html   (2501 words)

Boston Biomedical Research Institute The mass spectrometer is an instrument for determining the mass of molecules. Mass spectrometry can therefore be used in a wide range of applications in research laboratories or pharmaceutical companies. The ability of the mass spectrometer to analyze a complex mixture and its superb sensitivity make this instrument one of the most powerful tools in proteomics during the current post-genomic era. www.bbri.org /corefac/massspec.html   (366 words)

Advanced Environmental Monitoring and Control Program Today, JPL is developing even smaller mass spectrometers to monitor the air inside the space station and any future spacecraft that may travel to Mars or other extraterrestrial destinations. A mass spectrometer is a device that identifies chemicals by their molecular weight (approximately the combined number of a molecule's protons and neutrons). A typical mass spectrometer is about the size of a four or five-drawer filing cabinet, much too big and heavy for the confines of a spacecraft. aemc.jpl.nasa.gov /activities/mms.cfm   (1577 words)

Helium mass spectrometer - Wikipedia, the free encyclopedia A helium mass spectrometer (often called a leak detector) or sniffer, is a scientific instrument, used to detect very small leaks, typically using a vacuum and injecting helium around a chamber or cavity. The helium mass spectrometer leak detection technique depends on the separation of helium from other gasses in a vacuum, which is a relatively simple procedure. In the spectrometer tube, the heart of the helium mass spectrometer, the electrons produced by a hot filament enter an ion chamber under vacuum, and collide with gas molecules, creating within the chamber ions quantitively proportional to the pressure in the ion chamber. en.wikipedia.org /wiki/Helium_mass_spectrometer   (507 words)

Tandem Mass Spectrometry A tandem mass spectrometer is one of several types of analytical instruments known as mass spectrometers. Mass spectrometers are used in many laboratories throughout the world to analyze thousands of compounds such as those present in our bodies, our environment, our medicines, manufactured materials, foods, poisons, and criminal evidence. The mass of water is 18, common table salt (sodium chloride) is 58, and sucrose (from sugar cane) is 342. www.savebabies.org /NBS/msms-chace.php   (1691 words)

Mass Spectrometer   (Site not responding. Last check: 2007-10-03) A UTI Model 100C quadrupole mass spectrometer, capable of detecting molecules with mass to charge ratios from 1 to 300, is used to collect TPRS and ESD data. The spectrometer is enclosed by a shield with a 1/8" diameter aperture, to optimize detection of the molecules desorbing directly from the center of the crystal. The mass spectrometer signal of the gaseous desorption products is monitored as a function of both time and temperature using the TPRS98 program interfaced to the mass spectrometer and thermocouple. www.wellesley.edu /Chemistry/Chris/mass_spec.html   (172 words)

Waters Corporation - Mass Spectrometry ( Mass Spec ) Primer - The Mass Spectrometer With the usual nomenclature (m = mass, z = number of charges on an ion, e = the charge on an electron, v = the final velocity reached on acceleration), the kinetic energy (mv /2) of the ion is given by equation (1). Mass range: there is no upper theoretical mass limitation; all ions can be made to proceed from source to detector and the the upper mass limit exceeds 500 kDa. In practice, there is a mass limitation, in that it becomes increasingly difficult to discriminate between times of arrival at the detector as the m/z value becomes large. www.waters.com /WatersDivision/ContentD.asp?watersit=EGOO-66MNYR   (2328 words)

Mass Spectrometer: The Analyzer   (Site not responding. Last check: 2007-10-03) The mass spectrometer “smashes" the atom by overwhelming it with so much energy that it breaks apart. The quadrupole mass spectrometer used here is made with 4 rods of hyperbolic surfaces. The strength and frequency of the RF field determines whether or not an ion of a certain mass passes through the rods (and is counted by the detector) or smashes into a nearby surface. huygensgcms.gsfc.nasa.gov /MS_Analyzer_1.htm   (258 words)

the mass spectrometer - how it works Most of the ions passing through the mass spectrometer will have a charge of 1+, so that the mass/charge ratio will be the same as the mass of the ion. The mass of each ion being detected is related to the size of the magnetic field used to bring it on to the detector. Assuming that the ions all have a charge of 1+, that means that the masses of the 7 isotopes on the carbon-12 scale are 92, 94, 95, 96, 97, 98 and 100. www.chemguide.co.uk /analysis/masspec/howitworks.html   (1467 words)

Links to miniature mass spectrometer and mobile GC/MS The CBMS (Chemical Biological Mass Spectrometer) is a Membrane Inlet Ion-Trap from Bruker Mobile mass spectrometer for monitoring and forecasting emergencies from ROSOBORONEXPORT Federal State Unitary Enterprise is the major specialised agency responsible for Russian arms export. Investigation of Miniature Mass Spectrometers for Hydrogen Isotopic Analyses by the Savannah River Technology Center (Comparison of a Ferran Multipole MS, a Mass Sensors magnetic MS and a miniature ion trap based on ORNL design with a:SRS RGA 300). www.gcms.de   (1442 words)

ORNL Review: Mass Spectrometer Can Detect Weapons of Mass Destruction ORNL helped design the first portable mass spectrometer that can detect chemical warfare agents in the air and on the ground, as well as biological warfare agents in the air. It is an outgrowth of the ORNL-developed direct sampling ion trap mass spectrometer successfully deployed to identify and measure hazardous chemical pollutants in the field. In the spectrometer, the biomarker molecules are ionized and analyzed using MS/MS. www.ornl.gov /ORNLReview/v33_3_00/mass.htm   (829 words)

Recoil Mass Spectrometer (RMS) The recoil mass spectrometer (RMS) is a zero degree device used to separate masses produced in nuclear reactions. The spectrometer [1-6] is 25 m long and is comprised of a momentum separator for beam rejection and the traditional electric-magnetic-electric dipole mass separator [7-10]. A Recoil Mass Spectrometer for HHIRF, J.D. Cole, T.M. Cormier, J.H. Hamilton, and A.V. Ramayya, Nucl. www.phy.ornl.gov /hribf/research/equipment/rms   (1331 words)

Simultaneous Thermal Analysis/Mass Spectrometer A mass spectrometer (MS) is attached to the STA instrument for evolved gas analysis. Simultaneously, any change in mass of the specimen during a heating cycle can be measured with a microbalance as a function of temperature. During the thermal cycle, a capillary leak allows samples of the gaseous environment in the immediate vicinity of the specimen to be drawn into a quadruple mass spectrometer. www.ms.ornl.gov /htmlhome/tpuc/sta.html   (314 words)

ESA Science & Technology: Laser Mass Spectrometer The Laser Mass Spectrometer (LMS) is part of the actual challenge of reducing the size and the power consumption of various instruments to be accommodated on a lander or rover, for in-situ studies of planetary environment. Built around a miniature mass spectrometer and a laser ablation system; the LMS was designed initially to be deployed on an airless body, in the frame of the rover of the BepiColombo mission to Mercury. It combines a mass analyzer and an ion source where the ions are directly coupled into the mass analyzer after they were formed by green laser ablation. sci.esa.int /science-e/www/object/index.cfm?fobjectid=35986   (325 words)

Mass spectrometer The sector field mass spectrometers (SFMS) used for helium isotope and tritium measurement are commercial instruments (Fig. During automated operation, the mass spectrometers are pumped between measurements of individual samples or standards by ion getter pumps (Varian, StarCell VacIon Plus 40) attached to the flight tubes by pneumatically operated valves (VG, CR 38 TU, and VAT, Series 57, respectively). The sensitivity of the mass spectrometers is mainly a function of the source parameters: repeller, electron energy, focus, beam center and source magnet position. www.ldeo.columbia.edu /~etg/ms_ms/Mass_spectrometer.html   (879 words)

Carnegie Mellon scientist to build unique mass spectrometer While mass spectrometers are routinely used to determine the weight, structure and amount of small molecules or fragments of molecules, commercial instruments are not equipped to sensitively characterize large molecules over 150 kiloDaltons (a measure of mass). A typical mass spectrometer consists of three components: an ion source to electrically charge the sample; a mass analyzer to separate the newly charged ions by their unique mass-to-charge ratio; and a detector to generate a recordable ion signal. Bier's mass spectrometer is unique because it combines a cryodetector with a linear ion trap, which he co-invented and patented while working at Thermo Electron Corporation. www.physorg.com /news9771.html   (776 words)

Mass Spectrometer for High Molecular Weight Ions and Charged Particles Berkeley Lab's mass spectrometer measures the mass of large ions more quickly and accurately than gel electrophoresis, which presently is the only competing method capable of analyzing large ion masses. Ion mass is calculated directly from these measurements and knowledge of ion energy.The system measures individual ions; mass spectra are acquired by measuring a few thousand ions. Potentially, the mass spectrometer could also be used for weighing virus particles, organelles and large macromolecular complexes. www.lbl.gov /Tech-Transfer/techs/lbnl1127.html   (281 words)

Laboratory Products are based on mass spectrometer chip., Microsaic Systems Limited The performance of a mass spectrometer depends on its mechanical precision; the more perfectly aligned the components are, the better the system's sensitivity and selectivity. In this way, entire batches of identical quadrupole mass spectrometer chips may be manufactured from silicon wafers. Mass spectrometers are sophisticated systems used in everything from explosives detection to drug discovery. news.thomasnet.com /fullstory/476545/rss   (904 words)

Mass Spectrometry ( Mass Spec ) Primer - Waters Corporation The "heart" of the mass spectrometer is the analyzer. Since the motion and separation of ions is based on electrical or magnetic fields, it is the mass to charge ratio, and not only the mass, which is of importance. Mass accuracy: indicates the accuracy of the mass information provided by the mass spectrometer. www.waters.com /watersdivision/ContentD.asp?watersit=EGOO-66LRQD   (990 words)

IB Chemistry higher level notes: Atomic theory - the mass spectrometer Measuring the masses of the breakdown products from molecules when they are smashed to pieces by high energy electrons. The mass spectrum shows that the peaks are in the ratio 10:1 and so there is 10 times as much Ne as Ne in the sample. The relative atomic mass is the weighted average of the isotope masses. ibchem.com /IB/ibnotes/full/ato_htm/12.1.htm   (656 words)

New mass-spectrometer analyzes proteins faster and at a lower cost The device is a critical component of a mass spectrometer, an instrument that can detect proteins present even in ultra-small concentrations by measuring the relative masses of ionized atoms and molecules. Mass spectrometers can provide a complete protein profile and essentially make proteomics, the study of how proteins are produced and interact within an organ, cell or tissue, possible. In the future, with a powerful and portable mass spectrometer, it may be possible for a doctor to take a sample directly from the patient, place it in the device and receive an analysis on the spot. www.physorg.com /news4425.html   (882 words)

Cassini-Huygens: Spacecraft-Instrument-Ion and Neutral Mass Spectrometer (INMS) The Ion and Neutral Mass Spectrometer (INMS) is intended to measure positive ion and neutral species composition and structure in the upper atmosphere of Titan and magnetosphere of Saturn, and to measure the positive ion and neutral environments of Saturn's icy satellites and rings. The Ion and Neutral Mass Spectrometer Subsystem (INMS) will be used to study the neutral gases and positive ions in the atmospheres of Saturn and Titan and gases in the vicinities of the Saturnian rings and the icy satellites. The transmitted mass, the resolution, and the ion transmission are controlled by variations in RF and d.c. saturn.jpl.nasa.gov /spacecraft/inst-cassini-inms-details.cfm   (427 words)

Micro Ion Trap Mass Spectrometer   (Site not responding. Last check: 2007-10-03) The traps are operated in the mass-selective instability mode in the same manner as the larger conventional ion traps, but the voltage and frequency of the voltage on the ring electrode are different. A mass spectrum of xenon obtained with the trap described above is shown. From an analysis of the variation of the peak heights from scan to scan, we estimate that a lower limit of approximately 800 ions were trapped per scan. www.ornl.gov /lsm/microiontrapMS.html   (338 words)

University Mass Spectrometer Facilities - Listing of The Mass Spectrometry Team in CST-8 is equipped with two state-of-the-art Thermal Ionization Mass Spectrometers (TIMS) one of which has negative ion capabilities, a new double-focusing Glow Discharge Mass Spectrometer (GDMS), a magnetic sector Gas Mass Spectrometer, and associated subsystems. Thomas G. Hartman, an instrumentation specialist with expertise in mass spectrometry and othe analytical techniques is responsible for the mangement of the facility. The mass spectrometry resource at Washington University-St. Louis is a merger of the former NSF Midwest Center for Mass Spectrometry (founded in 1978 at the University of Nebraska) and the Biomedical Mass Spectrometry Resource (founded in 1976 at Washington University). www.sisweb.com /referenc/sites/univ-ms.htm   (2083 words)

Try your search on: Qwika (all wikis)

About us   |   Why use us?   |   Reviews   |   Press   |   Contact us   Copyright © 2005-2007 www.factbites.com Usage implies agreement with terms.