refimprove date August 2009 In particle physics , gaseous ionization detectors are detectors designed to seek the presence of particles a particle detector . If a particle has enough energy to ion ize a gas atom or molecule, the resulting electron s and ion s cause a current flow which can be measured in different ways. The three basic types of gaseous ionization detectors are ionization chamber s proportional counter s Geiger M ller tube s All of these have the same basic design of two electrode s separated by air or a special counting gas, but each uses a unique method to form the total number of ion pairs that are collected. ref McGregor, Douglas S. Chapter 8 Detection and Measurement of Radiation. Fundamentals of Nuclear Science and Engineering, Second Edition. By Kenneth J. Shultis and Richard E. Faw. 2nd ed. CRC, 2007. 202 222. Print. ref The strength of the electric field between the electrodes determines the detector s response to ionizing radiation . Ionization chamber s operate at a low voltage, selected such that no avalanche multiplication takes place. Current is generated by the drift of ions to anode or cathode. Proportional counter s operate at a slightly higher voltage, selected such that limited avalanche multiplication takes place. The avalanche is localised, rather than spreading widely through the detecting gas, so that an output current pulse is generated which is proportional to the detected particle energy. The term gas proportional detector GPD is generally used in radiometric practice, and the property of being able to detect particle energy is particular ... Mueller counter. Wire chamber s are essentially gaseous ionization detectors with many electrodes instead of one. Ionization type smoke detector s are gaseous ionization detectors. A bit of radioactive ... the plates where the ionization is taking place, the ionized gas can be neutralized leading to a reduced current. The decrease in current triggers a fire alarm. Notes references DEFAULTSORT Gaseous Ionization ... more details
Ultrasonication Assisted Spray Ionization UASI introduced by the group of Yu Chie Chen is an ionization technique an ion source , used with atmospheric pressure mass spectrometry , which involves application of ultrasound s. ref cite web last Chen first Tsung Yi title Ultrasonication assisted spray ionization mass spectrometry for the analysis of biomolecules in solution url http www.springerlink.com content y320pk32267kp224 work Journal of the American Society for Mass Spectrometry accessdate 4 November 2011 coauthors Lin, Jia Yi, Chen, Jen Yi, Chen, Yu Chie pages 1547 1553 doi 10.1016 j.jasms.2010.04.021 ref ref cite web last Chen first Tsung Yi title Ultrasonication assisted spray ionization mass spectrometry for on line monitoring of organic reactions url http pubs.rsc.org en Content ArticleLanding 2010 CC C0CC02629H work Chemical Communications accessdate 4 November 2011 coauthors Chao, Chin Sheng, Mong, Kwok Kong Tony, Chen, Yu Chie pages 8347 doi 10.1039 C0CC02629H date 4 November 2010 ref References Reflist Category Ion source Category Articles created via the Article Wizard Chemistry stub ... more details
Orphan date July 2011 Laser spray ionization refers to one of several methods for creating ions using a laser interacting with a spray of neutral particles ref name jms.621 cite journal doi 10.1002 jms.621 year 2004 month April first Kenzo last Hiraoka title Laser spray electric field assisted matrix assisted laser desorption ionization volume 39 issue 4 pages 341 50 issn 1076 5174 pmid 15103647 journal Journal of Mass Spectrometry ref ref Cite journal doi 10.1016 S0021 9673 00 89972 0 title Crossed beam liquid chromatoraph mass spectrometer combination year 1978 last1 Blakley first1 C last2 McAdams first2 M last3 Vestal first3 M journal Journal of Chromatography A volume 158 pages 261 ref ref cite journal title Laser Spray Ionization for Biological Mass Spectrometry journal American Laboratory year 1994 first K. K. last Murray coauthors D. H. Russell volume 26 issue 9 pages 38 44 id url format accessdate 2010 05 04 ref or ablating material to create a plume of charged particles. ref name mcp Cite journal doi 10.1074 mcp.M900527 MCP200 title Laserspray Ionization, a New Atmospheric Pressure MALDI Method for Producing Highly Charged Gas phase Ions of Peptides and Proteins Directly from Solid Solutions year 2009 last1 Trimpin first1 S. last2 Inutan first2 E. D. last3 Herath first3 T. N. last4 McEwen first4 C. N. journal Molecular & Cellular Proteomics volume 9 pages 362 7 pmid 19955086 ... were found to be orders of magnitude greater than those obtained by conventional electrospray ionization in the case of aqueous solutions. This approach to laser spray ionization is a hybrid of three ... successfully applied to evaluate the binding affinities of protein DNA . Laser spray has better ionization efficiency than conventional electrospray ionization ESI . ref name jms.621 In particular, the sensitivity ... ionization LSI without the space between laser and spray is so named to reflect the similarity with ESI using a matrix assisted laser desorption ionization MALDI method. Laser ablation of a solid matrix ... more details
math represents the number of photons absorbed, math W math is the ionization energy work function and math ... in non perturbative time dependent calculation of above threshold ionization journal Journal ... ref cite journal doi 10.1103 PhysRevA.38.3430 title Numerical simulations of multiphoton ionization ... Threshold Ionization photoelectron spectra Category Atomic, molecular, and optical physics Atomic ... more details
Infobox laboratory equipment name Hot filament ionization gauge image Bayard Alpert gauge.jpg alt See Wikipedia Alternative text for images caption Bayard Alpert hot thoriated iridium filament ionization gauge on 2.75 Inch in conflat flange acronym other names Hot cathode gauge br Bayard Alpert gauge uses Pressure measurement inventor manufacturer model related The hot filament ionization gauge , sometimes called a hot filament gauge or hot cathode gauge , is the most widely used low pressure vacuum measuring device for the region from 10 sup 3 sup to 10 sup 10 sup Torr unit torr . It is a triode , whereas the filament is the cathode . Note Principles are mostly the same for hot cathode ion sources in particle accelerator s to create electrons Function A regulated electron current typically 10 Ampere mA is emitted from a heated Electrical filament filament . The electrons are attracted to the helical grid by a dc potential of about 150 volts. In their passage from the filament to the control grid grid , the electrons collide with gas molecules in the gauge envelope, causing a fraction of them to be ionized. The gas ions formed by the electron collisions are attracted to the central ... filament ionization gauge is composition dependent. Over a wide range of molecular density ... px Tubulated hot cathode ionization gauge. A hot cathode ionization gauge is composed mainly of three ... ionization . The number of these ions is proportional to the gaseous molecule density multiplied ... . In this case a valve lets gas into the grid cage. Types of hot filament ionization gauges Bayard Alpert ... the vacuum chamber to make a complete seal . See also Ionization gauge Vacuum Electron ionization ... Hot filament ionization gauge tubes http www.patentgenius.com patent 4792763.html U.S. Patent 4792763 Hot cathode ionization pressure gauge http www.patentgenius.com patent 5373240.html U.S. Patent 5373240 Hot cathode ionization pressure gauge including a sequence of electrodes arranged at a distance ... more details
electron interacting with an ionic core. Techniques Resonance ionization spectroscopy RIS The ionization ... easily available experimentally. However, it can be possible to span this ionization threshold ... molecules, Rydberg states are even more important in laser ionization experiments. Laser spectroscopic experiments often involve ionization through a photon energy resonance at an intermediate ... makes ionization an expected outcome. This RIS approach and variations permit very sensitive detection ... is exploited in Resonance Enhanced Multiphoton Ionization Spectroscopy REMPI . An advantage of this spectroscopic ... that produces an ionization event can be used to access the dense manifold of near threshold Rydberg ... ZEKE was developed with the idea of collecting only the resonance ionization photoelectrons that have ... ionization experiment and then pulsing an electric field to collect the lowest energy photoelectrons ... state at a multiphoton transition. Another photon energy is tuned to be very close to the ionization ... analyzed threshold ionization MATI was developed with idea of collecting the mass of the ions in a ZEKE .... PIRI Photo induced Rydberg ionization PIRI was developed following REMPI experiments on electronic ... autoionization could dominate the direct single photon absorption in the ionization of some Rydberg ... more details
Legionnaires disease . Process Copper silver ionization is a dispersive process that introduces .... ref name iche Over the long term, ionization thus disperses and destroys biofilms and slimes that can ... Science Center explains that copper silver ionization is a modern implementation of the ancient ... and fungi with copper. Fornshell notes that copper silver ionization has been effective in swimming ... 2008 Replacing chlorination with copper silver ionization to keep water safe was one response of Frederick ... . sfn Sheerin 2003 Ionization is in many cases installed because more convenient and cost effective than other approaches. ref name iche Effectiveness Ionization is an effective industrial control ... towers found in health facilities, hotels, nursing homes and most large buildings. In 2003, ionization ... time. ref Additional studies indicate ionization is superior to thermal eradication. sfn Block 2001 ... evaluating 79 research papers found Copper Silver ionization to be the only Legionella control ... silver ionization technology is recognized by the WHO, the U.S. Environmental Protection Agency ... iche Industry leaders who manufacture copper silver ionization technology recommends copper concentration ... U.K. ionization, advising regular system monitoring to ensure ions reach all water circuits ... Hayes first John title Copper silver ionization gaining approval accessdate 2009 03 02 ref harv cite ... 16 Hospitals Using Copper Silver Ionization for Legionella Control Implications for the Evaluation ... 26 ai 84428202 title Hospitals turn to ionization method for controlling Legionella infections What ... silver ionization 22 title Disinfection, Sterilization, and Preservation edition 5th last Block first ... more details
Unreferenced stub auto yes date December 2009 Context date September 2008 A helium ionization detector HID is a type of detector used in gas chromatograph y. Principle An HID is an GC ion detector ion detector which uses a radioactive source to produce ion s. The radioactive source ionizes helium atoms by bombarding them with emissions. As components elute from the gas chromatograph GC s column they are mixed with the helium ions, which then ionize the components. The ion s produce an electric current , which is the signal information theory signal output of the detector. The greater the concentration of the component, the more ions are produced, and the greater the current. Application HIDs are sensitive to a broad range of components. They must use helium as a carrier gas. HIDs are non destructive detectors. They do not destroy consume the components they detect. Therefore they can be used before other detectors in multiple detector configurations. The drawback to HIDs are that they contain a radioactive source. In the U.S. , this means they fall under a number of federal regulations concerning their use in the workplace, shipping, disposal, etc. Discharge ionization detector s have generally supplanted them. DEFAULTSORT Helium Ionization Detector Category Gas chromatography Analytical chemistry stub ... more details
Cleanup rewrite date October 2008 no footnotes date July 2011 File Flame ionization detector schematic.gif thumb right 200 px Schematic of a flame ionization detector for gas chromatography A flame ionization detector FID is a type of gas detector used in gas chromatograph y. The first flame ionization detector was developed in 1957 by scientists working for the CSIRO in Melbourne , Australia . ref Scott, R. P. W., 1957, Vapour Phase Chromatography, Ed. D. H. Desty London Butterworths , p. 131. ref ref cite journal title Flame Ionization Detector for Gas Chromatography journal Nature date first last coauthors volume 181 issue 4611 pages 760 doi 10.1038 181760a0 url format last1 McWilliam first1 I. G. last2 Dewar first2 R. A. ref ref cite journal title Construction and operation of a simple flame ionization detector for gas chromatography journal J. Sci. Instrum. year 1961 first last coauthors volume 38 issue 12 pages 501 id url http iopscience.iop.org 0950 7671 38 12 321 format accessdate 2009 03 18 doi 10.1088 0950 7671 38 12 321 author Morgan, D J ref The detection of organic compound s is most effectively done with flame ionization. Biochemical compounds such as proteins, nucleotides, and pharmaceuticals can be studied with flame ionization as well as other detectors, like Thermal ... that a particular compound may be more easily detected using flame ionization over the other methods because of higher carbon concentration and also flame ionization s sensitivity. Application ... Image Flame Ionization Detector.svg frame right FID Schematic The design of the flame ionization ... ionization detector journal Journal of Chromatography A date first last coauthors volume 842 issue .... Some of the benefits of a flame ionization detector are quite useful. FIDs are insensitive to H sub ... with Capillary Column and Flame Ionization Detector. Analytical Chemistry. 33, 8 July 1961 ... simple Flame ionization detector ... more details
Contactless Atmospheric Pressure Ionization or Contactless API introduced by the group of Yu Chie Chen is a technique an ion source used for analysis of liquid and solid samples by mass spectrometry . Contactless API can be operated without an additional electric power supply supplying voltage to the source emitter , gas supply, or syringe pump . Thus, the technique provides a facile means for analyzing chemical compound s by mass spectrometry at atmospheric pressure . References See http en.wikipedia.org wiki Wikipedia Footnotes on how to create references using ref ref tags which will then appear here automatically Reflist Capillary Action Supported Contactless Atmospheric Pressure Ionization for the Combined Sampling and Mass Spectrometric Analysis of Biomolecules Analytical Chemistry 2011, 83, 2866 2869. http pubs.acs.org doi abs 10.1021 ac200479s Categories Category Ion source Category Articles created via the Article Wizard Sci stub ... more details
Thermal ionization mass spectrometry TIMS is a highly sensitive isotope mass spectrometry characterization technique in which a chemically purified sample is heated to cause ionization of the atoms of the sample. The ions are focused into a beam by an electromagnet, then separated into individual beams based on the mass charge ratio of the ions. The technique is used extensively in isotope geochemistry, geochronology , and in cosmochemistry. TIMS is a Sector instrument magnetic sector mass spectrometry technique in which ions are separated as a function of their charge and velocity or mass in a magnetic field. The relative abundances of different isotopes are then used to describe the chemical fractionation of different isotopes, travel in different reservoirs of non radiogenic isotopes, and age or origins of solar system objects by the presence of radiogenic daughter isotopes. ref name LehtoHou Lehto, J., X. Hou, 2011. Chemistry and Analysis of Radionuclides. Wiley VCH. ref ref name Dickin Dickin, A.P., 2005. Radiogenic Isotope Geology 2nd ed. Cambridge Cambridge University Press. pp. 21 22 ref References Reflist mass spectrometry Category Mass spectrometry ... more details
The Saha ionization equation , also known as the Saha Langmuir equation , was developed by the Indian astrophysicist Meghnad Saha in 1920, and later 1923 by Irving Langmuir . One of the important applications of the equation was in explaining the spectral classification of stars. The equation is a result of combining ideas of quantum mechanics and statistical mechanics. For a gas at a high enough temperature, the thermal collisions of the atoms will ionize some of the atoms. One or more of the electrons that are normally bound to the atom in orbits around the atomic nucleus will be ejected from the atom and will form an electron gas that co exists with the gas of atomic ions and neutral atoms. This state of matter is called a Plasma physics plasma . The Saha equation describes the degree of ionization of this plasma as a function of the temperature, density, and ionization energies of the atoms ... is negligible. The subsequent lowering of the ionization potentials and the cutoff of the Partition ... of atoms in the i th state of ionization, that is with i electrons removed. math g i , math is the Degenerate ... is the energy required to remove the math i 1 th math electron. In the case where only one level of ionization ... exp left frac epsilon k BT right math where math epsilon math is the energy of ionization. The Saha equation is useful for determining the ratio of particle densities for two different ionization levels ... s math mu i mu i 1 mu e , math This equation simply states that the potential for an atom of ionization state i to ionize is the same as the potential for an electron and an atom of ionization state i 1 the potentials are equal, therefore the system is in equilibrium and no net change of ionization ... out of the equilibrium properties of matter. He used this to provide a rigorous derivation of the ionization formula which as described earlier Saha had obtained by extending and justifiably to ionization ... atmosphere and calculating the temperature where increasing ionization, for example, inhibited ... more details
Image Critical ionization velocity.jpg thumb 300px Critical ionization velocity experiment onboard space ... ionization velocity CIV, also called Critical velocity , CV is the relative velocity between a neutral ... energy is supplied, the velocity of the atoms or molecules will not exceed the critical ionization ... key AST& data type HTML& format & high 42ca922c9c28386 Critical ionization velocity interactions ... & high 42ca922c9c03435 A review of critical ionization velocity 2001 Reviews of Geophysics , Volume ... 1961 . In 1973, Lars Danielsson published a review of critical ionization velocity, and concluded ... In the laboratory, critical ionization velocity has been recognised for some time, and is seen in the penumbra ... not been confirmed. In 1986, Gerhard Haerendel, suggested that critical velocity ionization may stabilize ... Plasma flow and critical velocity ionization in cometary comae , 1986 Geophys. Res. Lett . 13 25 5 ref . In 1992, E. Golbraikh and M. Filippov argued that critical ionization velocity could play ... format & high 42ca922c9c03435 Possible manifestation of the critical ionization velocity phenomenon ... of critical velocity ionization, ref Peratt, Anthony Verschuur, Gerrit, http adsabs.harvard.edu ... high 42ca922c9c03435 The Critical Ionization Velocity Signature Manifested in Interstellar Neutral ... 4 bgcolor eeeeee Typical Critical Ionization Velocities br After Alfv n 1976 td tr tr align center ... Oxygen td td 13.5 td td 16.0 td td 12.7 td tr table Mathematically, the critical ionization velocity ... energy is equal to the ionization energy, that is math frac 1 2 mv 2 eV ion math where eV sub ion sub is the ionization potential of the atoms or molecules in the gas cloud, m is the mass, v is the velocity. The phenomenon is also called the Critical velocity ionization , ref G. Haerendel http ... format & high 42ca922c9c32239 Plasma flow and critical velocity ionization in cometary comae ... to rise, so that at a certain distance from the Sun, the gas will ionize. Alfv n writes that the ionization ... more details
Laser Ablation Electrospray Ionization LAESI is an ambient ionization method for mass spectrometry that combines laser ablation from a mid infrared mid IR laser with a secondary electrospray ionization ESI process. The mid IR laser is used to generate gas phase particles which are then ionized through interactions with charged droplets from the ESI source. LAESI was developed by Professor Akos Vertes and Dr. Peter Nemes in 2007 and is now marketed commercially by Protea Biosciences, Inc. LAESI is a novel ionization source for mass spectrometry MS that has been used to perform MS imaging of plants .... First, the laser produces a small hemispherical plume over the sample without ionization Step ... ablation ionization ref name LAESIref18 . The jet of ablated material is intersected and ionized by a spray ... into the mass spectrometer for analysis Step 4 . Because an ESI source is used for ionization ... ac071181r Nemes, P. Vertes, A., Laser ablation electrospray ionization for atmospheric pressure, in vivo ... Imaging and Depth Profiling of Live Tissue by Infrared Laser Ablation Electrospray Ionization Mass ... under Ambient Conditions by Laser Ablation Electrospray Ionization Mass Spectrometry. Analytical ... laser ablation electrospray ionization mass spectrometry. Metabolomics 2009, 5, 2 , 263 276 ref ... Electrospray Ionization Mass Spectrometry. Analytical Chemistry 2010, 82, 3 , 982 988 ref ref ... Ionization Mass Spectrometry. Analytical Chemistry 2009, 81, 20 , 8265 8271 ref ref name LAESIref11 ... monitoring of cellulose degradation by desorption electrospray ionization and laser ablation electrospray ionization mass spectrometry. Analyst 2010, 135, 2434 2444 ref ref name LAESIref13 http dx.doi.org 10.1007 978 1 60761 746 4 9 Nemes, P. Vertes, A., Laser Ablation Electrospray Ionization for Atmospheric ... Biosciences, Inc. http www.gwu.edu vertes Vertes Lab at George Washington University Ambient ionization Ambient Ionization Mass Spectrometry Category Mass spectrometry ... more details
et al. , Pulsed Discharge Helium Ionization Detector , Chromatographia, Volume 34, September October 1992, Numbers 5 8, Pages 219 225 W. E. Wentworth et al. , Pulsed Discharge Helium Ionization ... more details
Negative air ionization therapy is the use of air ioniser s as an experimental non pharmaceutical treatment for seasonal affective disorder SAD and mild Depression mood depression . For SAD, a randomized controlled trial RCT comparing high 4.5x10 sup 14 sup ions second and low 1.7x10 sup 11 sup ions second flow rate negative air ionization with bright light therapy found that posttreatment improvement results were 57.1 for bright light 10,000 lux compared with high density ions, 47.9 and low density ions, 22.7 . ref name pmid17151164 cite doi 10.1176 appi.ajp.163.12.2126 ref An older RCT conducted by the same authors also found air ionization effective for SAD at 2.7x10 sup 6 sup ions cm sup 3 sup . can someone convert these so they can be compared? ref name pmid9783557 cite doi 10.1001 archpsyc.55.10.875 ref A 2007 review considers this therapy under investigation , and suggests that it may be a helpful treatment for SAD. ref name pmid18058281 cite doi 10.1080 10401230701653476 ref A RCT comparing the short term effects of bright light, an auditory stimulus, and high and low density negative ions on mood and alertness in mildly depressed and non depressed adults found that the three active stimuli, but not the low density placebo, reduced depression on the Beck Depression Inventory scale the auditory stimulus, bright light and high density ions all produced rapid mood changes&mdash with small to medium effect size s&mdash in depressed and non depressed subjects. ref name pmid16756690 cite doi 10.1017 S0033291706008002 ref Michael Terman, professor of clinical psychology in the Department of Psychiatry at Columbia University , who conducted the two studies on SAD, suggests that the mechanism responsible for the effect of this therapy on SAD is that the negative ion machines used in his studies are designed to mimic summer like conditions by supplementing the sparse winter ... inquiry.asp?SI 102 accessdate 2009 03 09 title I haven t heard of negative air ionization therapy ... more details
File Autoprotolyse eau.svg thumb upright 1.5 Acids and bases The self ionization of water also autoionization of water , and autodissociation of water is an ionization reaction in properties of water pure water or an aqueous solution , in which a water molecule, H sub 2 sub O, deprotonation loses the nucleus of one of its hydrogen atoms to become a hydroxide ion, OH sup sup . The hydron chemistry hydrogen nucleus, H sup sup , immediately protonation protonates another water molecule to form hydronium , H sub 3 sub O sup sup . It is an example of autoprotolysis , and exemplifies the amphoteric nature of water. Concentrations Chemically pure water has an electrical Conductivity electrolytic conductivity of 0.055 Siemens unit µ S cm sup 1 sup . According to the theories of Svante Arrhenius , this must be due to the presence of ions. The ions are produced by the self ionization reaction H sub 2 sub O H sub 2 sub O eqm H sub 3 sub O sup sup OH sup sup This equilibrium applies to pure water and any aqueous solution. The chemical equilibrium constant , K sub eq sub , for this reaction is given by math K eq frac H 3O OH H 2O 2 math If the concentration chemistry concentration of dissolved solution solutes is not very high, the concentration H sub 2 sub O can be taken as being constant at ca. 55.5M. ref McMurry, John. 2004 Organic Chemistry, pg 44 ref The ionization constant , dissociation constant , self ionization constant , or ionic product of water, symbolized by K sub w sub is given by math K w H 3O OH K eq times H 2O 2 math where H sub 3 sub O sup sup is the concentration ... ionization constant at 25 MPa Image Pressure dependence water ionization pKw on P.svg thumb 300px Pressure dependence of the water ionization constant at 25 C File Kw vs I.png thumb 270px Variation ... ionization on temperature and pressure has been investigated thoroughly. ref http www.iapws.org International ... Chemical equilibria DEFAULTSORT Self Ionization Of Water Category Water chemistry Category Equilibrium ... more details
Image ATIC launch.jpg thumb right 200px Launch of ATIC The Advanced Thin Ionization Calorimeter ATIC is a balloon aircraft balloon borne instrument flying in the stratosphere over Antarctica to measure the energy and composition of cosmic rays . ATIC was launched from McMurdo Station for the first time in December 2000 and has since completed three successful flights out of four. ref name nyt Cite news last Overbye first Dennis title A Whisper, Perhaps, From the Universe s Dark Side work The New York Times date 2008 11 25 url http www.nytimes.com 2008 11 25 science 25dark.html?8dpc &pagewanted all ref Working principle The detector uses the principle of ionization calorimetry several layers of the scintillator bismuth germanate emit light as they are struck by particles, allowing to calculate the particles energy. A silicon matrix is used to determine the particles electrical charge . ref http atic.phys.lsu.edu aticweb Instrument.html Instrument description , LSU Space Science group. Retrieved 23 November 2008 ref Collaborators The project is an international collaboration of researchers from Louisiana State University , University of Maryland, College Park , Marshall Space Flight Center , Purple Mountain Observatory in China, Moscow State University in Russia and Max Planck Institute for Solar System Research in Germany. ATIC is supported in the United States by NASA and flights are conducted under the auspices of the Balloon Program Office at Wallops Flight Facility by the staff of the Columbia Scientific Balloon Facility . Antarctic logistics are provided by the National Science Foundation and its contractor Raytheon Polar Services Corporation. The principal investigator for ATIC is John Wefel of Louisiana State University. Image ATIC closeup.jpg thumb left 150px Team and closeup of the instrument Results In November 2008, researchers published in Nature the finding ... Thin Ionization Calorimeter ... more details
Surface assisted laser desorption ionization SALDI introduced by Jan Sunner , Edward Dratz , and Yu Chie Chen in 1995 is an ionization technique used for analyzing biomolecule s by mass spectrometry 1,2 . In its first embodiment, it used graphite matrix 1 . At present, laser desorption ionization methods using other inorganic matrices, such as nanomaterials , are often regarded as SALDI variants. A related method named ambient SALDI which is a combination of conventional SALDI with ambient mass spectrometry incorporating the DART ion source has also been demonstrated 3 . See also Matrix assisted laser desorption ionization Soft laser desorption References Reflist 1 cite journal doi 10.1021 ac00119a021 title Graphite surface assisted laser desorption ionization time of flight mass spectrometry of peptides and proteins from liquid solutions year 1995 last1 Sunner first1 Jan last2 Dratz first2 Edward last3 Chen first3 Yu Chie journal Analytical Chemistry volume 67 issue 23 pages 4335 42 pmid 8633776 2 cite journal pages 153 61 doi 10.1586 14789450.3.1.153 title Surface assisted laser desorption ionization mass spectrometry year 2006 last1 Dattelbaum first1 Andrew M last2 Iyer first2 Srinivas journal Expert Review of Proteomics volume 3 pmid 16445359 issue 1 3 Graphite Coated Paper as Substrate for High Sensitivity Analysis in Ambient Surface Assisted Laser Desorption Ionization Mass Spectrometry http pubs.acs.org doi abs 10.1021 ac300002g Categories Category Articles created via the Article Wizard Category Mass spectrometry Category Ion source analytical chem stub ... more details
called electrospray assisted laser desorption ionization ELDI uses an ultraviolet laser to form ions ... I, Sunner J title Electrospray assisted laser desorption ionization mass spectrometry for direct ambient ... ablation electrospray ionization LAESI ref name pmid17900146 cite journal author Nemes P, Vertes A title Laser Ablation Electrospray Ionization for Atmospheric Pressure, in Vivo, and Imaging Mass Spectrometry ... 10.1021 ac071181r ref or, alternately, infrared laser assisted desorption electrospray ionization IR ... Aerosol Desorption Electrospray Ionization title 55th ASMS Meeting editor first editor last coeditors ... ionization mass spectrometry volume 133 issue 2 pages 226 32 pmid 18227946 journal The Analyst ... tip to heat the sample and aid in ionization. ref Blakley, C. R. Carmody, J. J. Vestal, M. L. Liquid ... more details
Infobox chemical analysis name Surface enhanced laser desorption ionization image caption acronym SELDI classification analytes Biomolecule s manufacturers related Matrix assisted laser desorption ionization br Soft laser desorption hyphenated Surface enhanced laser desorption ionization SELDI is an ionization method in mass spectrometry that is used for the analysis of protein mixture s. ref cite journal author Tang N, Tornatore P, Weinberger SR title Current developments in SELDI affinity technology journal Mass spectrometry reviews volume 23 issue 1 pages 34 44 year 2004 pmid 14625891 doi 10.1002 mas.10066 ref SELDI is typically used with time of flight mass spectrometry time of flight mass spectrometers and is used to detect proteins in tissue samples, blood , urine , or other clinical samples. Comparison of protein levels between patients with and without a disease can be used for biomarker discovery . ref cite journal author Li J, Zhang Z, Rosenzweig J, Wang YY, Chan DW title Proteomics and bioinformatics approaches for identification of serum biomarkers to detect breast cancer journal Clin. Chem. volume 48 issue 8 pages 1296 304 year 2002 pmid 12142387 ref ref cite journal author Jr GW, Cazares LH, Leung SM, Nasim S, Adam BL, Yip TT, Schellhammer PF, Gong L, Vlahou A title Proteinchip R surface enhanced laser desorption ionization SELDI mass spectrometry a novel protein biochip technology for detection of prostate cancer biomarkers in complex protein mixtures journal Prostate Cancer and Prostatic Diseases volume 2 issue 5 6 pages 264 276 year 1999 pmid 12497173 doi 10.1038 sj.pcan.4500384 ref How it works SELDI TOF MS is a variation of matrix assisted laser desorption ionization MALDI that uses a target modified to achieve chemical affinity biochemical affinity with the analyte compound. In MALDI, a protein or peptide sample is mixed with the matrix molecule in solution ... source es Surface enhanced laser desorption ionization ... more details
Image MALDITOF.jpg thumb right 200 px MALDI TOF mass spectrometer Matrix assisted laser desorption ionization MALDI is a soft ionization technique used in mass spectrometry , allowing the analysis of biomolecule ... when ionized by more conventional ionization methods. It is similar in character to electrospray ionization both in relative softness and the ions produced although it causes many fewer multiply ... nanodroplets . The second step is ionization more accurately protonation or deprotonation . Protonation ... matrix for laser desorption ionization mass spectrometry journal Int. J. Mass Spectrom. Ion Processes ... to encourage ionization of the analyte. Basic matrices have also been reported. ref Fitzgerald et ... assisted laser desorption ionization mass spectrometry of proteins and oligonucleotides year ... . Although not as common, infrared lasers are used due to their softer mode of ionization. IR MALDI ... 2010 01 20 ref Ionization mechanism The laser is fired at the matrix crystals in the dried droplet ... molecules and other organic molecules. Atmospheric pressure matrix assisted laser desorption ionization Atmospheric pressure AP matrix assisted laser desorption ionization MALDI is an ionization technique ... desorption ionization mass spectrometry journal Anal. Chem. volume 72 issue 4 pages 652 7 year 2000 ... 2000 pmid 11080870 doi 10.1021 ac000530d ref or any other MS system equipped with Electrospray ionization ESI electrospray ionization or nanoESI source. Mass spectrometer Image MALDI Target.jpg thumb ... ionization process since the pulsed laser takes individual shots rather than working in continuous ... spectrometry The term matrix assisted laser desorption ionization MALDI was coined in 1985 by Franz ... 0168 1176 87 87041 6 ref The breakthrough for large molecule laser desorption ionization came in 1987 ... nitrogen laser for ionization. ref cite journal author Tanaka, K. Waki, H. Ido, Y. Akita, S. Yoshida, Y. Yoshida, T. title Protein and Polymer Analyses up to m z 100 000 by Laser Ionization Time of flight ... more details
Refimprove date January 2007 Fast Low Ionization Emission Region , or FLIER , is the name for volumes of gas with low ionization near the symmetry axis of many planetary nebula e. Red in color, they bolt out from planetary nebulae, clouds of ejected material from sunlike, old stars in the process of dying and exploding, at supersonic speeds. The Blinking Planetary features a set of FLIERs squirting horizontally from the nebula . ref Terzian, Yervant cite web url http myeducationresearch.org databases cgi bin kwq.asp?qu recnumber 20FBA20098067&FreeText &sc 2Fpierianp 2Ffba 2F title Clearest Images of Mysterious Cosmic Spouts FLIERS . Web links date 18 May 1743 work myeducationresearch.org, The Pierian Press, 17 Dec 1997. Online. Internet. accessdate 30 Nov 2010 ref Their outflow speeds are significantly higher than the nebulae in which they are embedded, and their ionizations are much lower. FLIERs high speeds suggest ages much younger than their parent nebulae, and their low ionizations indicate that the ultraviolet radiation that ionizes the gas around them does not penetrate into the FLIERs. A picture of the Blinking Planetary nebula was taken by the Hubble on 27 January 1996, and the estimated distance from the telescope to the nebula is about 0.7 kiloparsecs or 2,200 light years. Previously, nebulae and their FLIERs could be seen from ground based telescopes with limited clarity. The Hubble Space Telescope s Blinking Planetary image credit goes to astronomers Bruce Balick of the University of Washington Jason Alexander, University of Washington Arsen Hajian, U.S. Naval Observatory , Washington, D.C. Mario Perinotto, University of Florence Italy Patrizio Patriarchi, Arcetri Observatory Italy and Cornell s Terzian, who used a special instrument with the Hubble Telescope known as WFPC2 pronounced wiffpick two . Object NGC 7009, which also shows very prominent FLIERs, nicknamed the Saturn Nebula , was observed by the Hubble Space Telescope on 28 April 1996, and is one ... more details
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