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SIMS

SIMS

The process known as secondary ion mass spectrometry (SIMS) involves bombarding the surface to be tested with a stream of ions. The test piece then emits particles, some of which are themselves ions. These secondary ions are measured with a mass spectrometer to determine the quantitative elemental or isotopic composition of the surface. SIMS is the most sensitive surface analysis technique, but is more difficult to accurately quantify than some other techniques. The history of SIMS is largely developed in the book Secondary Ion Mass Spectrometry: Basic Concepts, Instrumental Aspects, Applications, and Trends: The first observation of ion-induced neutrals and positive ions was made by J.J.Thomson in 1910. Fundammental for SIMS was pioneered by Herzog and Viehboek, in 1949, at the University of Vienna, Austria. Two SIMS instruments were developped independently in the early 1960's. An american project, led by Liebel and Herzog was sponsoreed by the NASA at GCA Corp, Massachusetts, with the target of analyzing moon rocks. A french project was initiated at the University of Orsay by Raimond Castaing in the framework of the PhD thesis of Georges Slodzian. Both instruments were further manufactured respectively by GCA Corp and Cameca, in the Paris area which is still involved SIMS instrument in 2005. These first instruments were based onto a magnetic double focusing mass spectrometer. In the earliest 1970's, SIMS instruments were developped with Quadrupole spectrometers, firstly by Alfred Benninghoven at the University of Munster, Germany and K.Wittmack in the Munich area. In the earliest 1980's SIMS Instruments based on Time of Flight spectrometers were developped at the University of Munster by Benninghoven, Niehus and Steffens. Detection limits for most trace elements are between 1e12 and 1e16 atoms/cc. Because the primary beam erodes the surface, a depth profile (e.g., 1 micrometer deep) may be obtained from a time trace. The lateral resolution is determined by the width of the primary beam and can be better than 50 nanometers. In the field of Surface Analysis, it is usual to distinguish Static SIMS and Dynamic SIMS. Static SIMS is the process involved in surface atomic monolayer analysis, while Dynamic SIMS is the process involved in bulk analysis, closely related to the sputtering process. [http://www.eaglabs.com/ Evans Analytical Group] has excellent tutorial pages for SIMS [http://www.eaglabs.com/en-US/references/tutorial/simstheo/caistheo.html theory] and [http://www.eaglabs.com/en-US/references/tutorial/simsinst/caisinst.html instrumentation], where the book Secondary Ion Mass Spectrometry: Basic Concepts, Instrumental Aspects, Applications, and Trends, by A. Benninghoven, F. G. Rüdenauer, and H. W. Werner, Wiley, New York, 1987 (1227 pages), is cited as "the best SIMS reference". For a presentation describing Time of Flight SIMS see [http://www.eaglabs.com/en-US/presentations/TOFSIMS/Presentation_Files/index.html TOF SIMS presentation]. Category:Mass spectrometry ja:二次イオン質量分析法

Mass spectrometry

Mass spectrometry is an analytical technique which determines the mass-to-charge (m/z) ratio of ions. It is most generally used to find the composition of a physical sample by generating a mass spectrum representing the masses of the components of a sample. It has several broad applications: # Identifying unknown compounds by the mass of the compound and/or fragments thereof. # Determining the isotopic composition of one or more elements in a compound. # Determining the structure of compounds by observing the fragmentation of the compound. # Quantitating the amount of a compound in a sample using carefully designed methods (mass spectrometry is not inherently quantitative). # Studying the fundamentals of gas phase ion chemistry (the chemistry of ions and neutrals in vacuum). # Determining other physical, chemical or even biological properties of compounds with a variety of other approaches. A mass spectrometer is a device used for mass spectrometry, and produces a mass spectrum of a sample to find its composition. This is normally achieved by ionizing the sample and separating ions of differing masses and recording their relative abundance by measuring intensities of ion flux. A typical mass spectrometer comprises three parts: an ion source, a mass analyzer, and a detector.

How it works in layman terms

Different molecules have different masses, and this fact is used in a mass spectrometer to determine what molecules are present in a sample. For example, table salt (Na Cl), is vaporized (turned into gas) and broken down (ionized) into electrically charged particles, called ions, in the first part of the mass spectometer. The sodium ions and chloride ions have specific molecular weights. They also have a charge, which means that they will be moved under the influence of an electric field. These ions are then sent into an ion acceleration chamber and passed through a slit in a metal sheet. A magnetic field is applied to the chamber, which pulls on each ion equally and deflects them (makes them curve instead of travelling straight) onto a detector. The lighter ions deflect further than the heavy ions because the force on each ion is equal but their masses are not (this is derived from the equation

F=ma

which states that if the force remains the same, the mass and acceleration are inversely proportional). The detector measures exactly how far each ion has been deflected, and from this measurement, the ion's 'mass to charge ratio' can be worked out. From this information it is possible to determine with a high level of certainty what the chemical composition of the original sample was. This example was of a sector instrument, however there are many types of mass spectrometers that not only analyze the ions differently but produce different types of ions; however they all use electric and magnetic fields to change the path of ions in some way.

Instrumentation

Ion source

The ion source is the part of the mass spectrometer that ionizes the material under analysis (the analyte). The ions are then transported by magnetic or electrical fields to the mass analyzer. Techniques for ionization have been key to determining what types of samples can be analyzed by mass spectrometry. Electron ionization and chemical ionization are used for gases and vapors. In chemical ionization sources, the analyte is ionized by chemical ion-molecule reactions during collisions in the source. Two techniques often used with liquid and solid biological samples include electrospray ionization (due to John Fenn) and matrix-assisted laser desorption/ionization (MALDI, due to M. Karas and F. Hillenkamp). Inductively coupled plasma sources are used primarily for metal analysis on a wide array of samples types. Others include fast atom bombardment (FAB), thermospray, atmospheric pressure chemical ionization (APCI), secondary ion mass spectrometry (SIMS) and thermal ionisation.

Mass analyzer

Mass analyzer separate the ions according to their mass per charge (m/z). There are many types of mass analyzers. Usually they are categorized based on the principles of operation. Sector MS: It uses an electric and/or magnetic field to affect the path and/or velocity of the charged particles in some way. The force exerted by electric and magnetic fields are defined by the Lorentz force law: :

\mathbf
  = q (\mathbf + \mathbf \times \mathbf),

where E is the electric field strength, B is the magnetic field induction, q is the charge of the particle, v is its current velocity (expressed as a vector), and × is the cross product. All mass analyzers use the Lorentz forces in some way either statically or dynamically in mass-to-charge determination. As shown above, sector instruments change the direction of ions that are flying through the mass analyzer. The ions enter a magnetic or electric field which bends the ion paths depending on their mass-to-charge ratios (m/z), deflecting the more charged and faster-moving, lighter ions more. The ions eventually reach the detector and their relative abundances are measured. The analyzer can used to select a narrow range of m/z's or to scan through a range of m/z's to catalog the ions present. Besides the original magnetic-sector analyzers, several other types of analyzer are now more common, including time-of-flight, quadrupole ion trap, quadrupole and Fourier transform ion cyclotron resonance mass analyzers. TOFMS: Perhaps the easiest to understand is the Time-of-flight (TOF) analyzer. It boosts ions to the same kinetic energy by passage through an electric field and measures the times they take to reach the detector. Although the kinetic energy is the same, the velocity is different so the lighter more highly charged ion will reach the detector first. QMS: Quadrupole mass analyzers use oscillating electrical fields to selectively stabilize or destabilize ions passing through a RF quadrupole field. QIT: The quadrupole ion trap works on the same physical principles as the QMS, but the ions are traped and sequentially ejected. Ions are created and trapped in a mainly quadrupole RF potential and separated by m/z, non-destructively or destructively. There are many mass/charge separation and isolation methods but most commonly used is the mass instability mode in which the RF potential is ramped so that the orbit of ions with a mass

a>b

are stable while ions with mass b become unstable and are ejected on the z-axis onto a detector. The cylindrical ion trap mass spectrometer is a derivative of the quadrupole ion trap mass spectrometer. : See also the main article on quadrupole ion trap mass spectrometer Linear QIT: In the linear quadrupole ion trap the ions are trapped in a 2D quadrupole filed instead of the 3D quadrupole field of the QIT. FTMS: Fourier transform mass spectrometry measures mass by detecting the image current produced by ions cyclotroning in the presence of a magnetic field. Instead of measuring the deflection of ions with a detector such as a electron multiplier, the ions are injected into a Penning trap (a static electric/magnetic ion trap) where they effectively form part of a circuit. Detectors at fixed positions in space measure the electrical signal of ions which pass near them over time producing cyclical signal. Since the frequency of the ions' cycling is determined by its mass to charge ratio, this can be deconvoluted by performing a Fourier transform on the signal. FTMS has the advantage of improved sensitivity (since each ion is 'counted' more than once) as well as much higher resolution and thus precision. : See also the main article on Fourier transform ion cyclotron resonance Each analyzer type has its strengths and weaknesses. In addition, there are many more less common mass analyzers. Many mass spectrometers use two or more mass analyzers for tandem mass spectrometry (MS/MS).

Detector

The final element of the mass spectrometer is the detector. The detector records the charge induced or current produced when an ion passes by or hits a surface. In a scanning instrument the signal produced in the detector during the course of the scan versus where the instrument is in the scan (at what m/z) will produce a mass spectrum, a record of how many ions of each m/z are present. Typically, some types of electron multiplier is used, though other detectors (such as Faraday cups) have been used. Because the number of ions leaving the mass analyzer at a particular instant is typically quite small, significant amplification is often necessary to get a signal. Microchannel Plate Detectors are commonly used in modern commercial instruments. In FTMS, the detector consists of a pair of metal plates within the mass analyzer region which the ions only pass near. No DC current is produced, only a weak AC image current is produced in a circuit between the plates.

Hyphenated MS

Gas chromatography/MS

: See also the main article on Gas chromatography-mass spectrometry A common form of mass spectrometry is gas chromatography-mass spectrometry (GC/MS or GC-MS). In this technique, a gas chromatograph is used to separate compounds. This stream of separated compounds is fed on-line into the ion source, a metallic filament to which voltage is applied. This filament emits electrons which ionize the compounds. The ions can then further fragment, yielding predictable patterns. Intact ions and fragments pass into the mass spectrometer's analyser and are eventually detected.

Liquid chromatography/MS

: See also the main article on Liquid chromatography-mass spectrometry Similar to gas chromatography MS (GC/MS), liquid chromatography mass spectrometry (LC/MS or LC-MS) separates compounds chromatographically before they are introduced to the ion source and mass spectrometer. It differs from GC/MS in that the mobile phase is liquid, usually a combination of water and organic solvents, instead of gas. Most commonly, an electrospray ionization source is used in LC/MS.

IMS/MS

Ion mobility spectrometry/mass spectrometry is a technique where ions are first separated by drift time through some pressure of neutral gas given an electrical potential gradient before being introduced into a mass spectrometer. The drift time is a measure of the radius relative to the charge of the ion. The duty cycle of IMS (time over which the experiment takes place) is longer than most mass spectrometers such that the mass spectrometer can sample along the course of the IMS separation. This produces data about the IMS separation and the mass-to-charge ratio of the ions in a manner similar to LC/MS. Note, however, that the duty cycle of IMS is short relative to liquid chromatography or gas chromatography separations and can thus be coupled to such techniques producing triply hyphenated techniques such as LC/IMS/MS.

Tandem MS (MS/MS)

Tandem mass spectrometry involves multiple steps of mass selection or analysis, usually separated by some form of fragmentation. A tandem mass spectrometer is one capable of multiple rounds of mass spectrometry. For example, one mass analyzer can isolate one peptide from many entering a mass spectrometer. A second mass analyzer then stabilizes the peptide ions while they collide with a gas, causing them to fragment by collision-induced dissociation (CID). A third mass analyzer then catalogs the fragments produced from the peptides. Tandem MS can also be done in a single mass analyzer over time as in a quadrupole ion trap. There are various methods for fragmenting molecules for tandem MS, including collision-induced dissociation (CID), electron capture dissociation (ECD), infrared multiphoton dissociation (IRMPD) and blackbody infrared radiative dissociation (BIRD).

Applications

Isotope ratio MS

Mass spectrometry is also used to determine the isotopic composition of elements within a sample. Differences in mass among isotopes of an element are very small, and the less abundant isotopes of an element are typically very rare, so a very sensitive instrument is required. These instruments, sometimes referred to as isotope ratio mass spectrometers (IR-MS), usually use a single magnet to bend a beam of ionized particles towards a series of Faraday cups which convert particle impacts to electric current. A fast on-line analysis of deuterium content of water can be done using Flowing afterglow mass spectrometry, FA-MS. Probably the most sensitive and accurate mass spectrometer for this purpose is the accelerator mass spectrometer (AMS). Isotope ratios are important markers of a variety of processes. Some isotope ratios are used to determine the age of materials for example as in carbon dating.

Trace Gas Analysis

Several techniques use ions created in a dedicated ion source injected into a flow tube or a drift tube: selected ion flow tube (SIFT-MS), and proton transfer reaction (PTR-MS), are variants of chemical ionization dedicated for trace gas analysis of air, breath or liquid headspace using well defined reaction time allowing calculations of analyte concentrations from the known reaction kinetics without the need for internal standard or calibration.

Pharmcokinetics

Pharmacokinetics is often studied using mass spectrometry due to the complex nature of the matrix (often blood or urine) and the need for high sensitivity to observe low dose and long time point data. The most common instrumentation used in this application is LC-MS with a triple quadrupole mass spectrometer. Tandem mass spectrometry is usually employed for added specificity. Standard curves and internal standards are used for quantitation of usually a single pharmaceutical in the samples. The samples represent different time points as a pharmaceutical is administered and then metabolized or cleared from the body. Blank or t=0 samples taken before administration are important in determining background and insuring data integrity with such complex sample matrices. Much attention is paid to the linearity of the standard curve however it is not uncommon to use curve fitting with more complex functions such as quadratics since the response of most mass spectrometers is less than linear across large concentration ranges.

Mass spectrometry of proteins

Mass spectrometry is an important emerging method for the characterization of proteins. The two primary methods for ionization of whole proteins are electrospray ionization and matrix-assisted laser desorption ionization (MALDI). In keeping with the performance and mass range of available mass spectrometers, two approaches are used for characterizing proteins. In the first, intact proteins are ionized by either of the two techniques described above, and then introduced to a mass analyser. In the second, proteins are enzymatically digested into smaller peptides using an agent such as trypsin or pepsin. Other proteolytic digest agents are also used. The collection of peptide products are then introduced to the mass analyser. This is often referred to as the "bottom-up" approach of protein analysis. Whole protein mass analysis is primarily conducted using either time-of-flight (TOF) MS, or Fourier transform ion cyclotron resonance. These two types of instrument are preferable here because of their wide mass range, and in the case of FT-ICR, its high mass accuracy. Mass analysis of proteolytic peptides is a much more popular method of protein characterization, as cheaper instrument designs can be used for characterization. Additionally, sample preparation is easier once whole proteins have been digested into smaller peptide fragments. The most widely used instrument for peptide mass analysis is the quadrupole ion trap. Multiple stage quadrupole-time-of-flight and MALDI time-of-flight instruments also find use in this application.

Protein and peptide fractionation coupled with mass spectrometry

Proteins of interest to biological researchers are usually part of a very complex mixture of other proteins and molecules that co-exist in the biological medium. This presents two significant problems. First, the two ionization techniques used for large molecules only work well when the mixture contains roughly equal amounts of constituents, while in biological samples, different proteins tend to be present in widely differing amounts. If such a mixture is ionized using electrospray or MALDI, the more abundant species have a tendency to "drown" signals from less abundant ones. The second problem is that the mass spectrum from a complex mixture is very difficult to interpret due to the overwhelming number of mixture components. This is exacerbated by the fact that enzymatic digestion of a protein gives rise to a large number of peptide products. To contend with this problem, two methods are widely used to fractionate proteins, or their peptide products from an enzymatic digestion. The first method fractionates whole proteins and is called two-dimensional gel electrophoresis. The second method, high performance liquid chromatography is used to fractionate peptides after enzymatic digestion. In some situations, it may be necessary to combine both of these techniques. Gel spots identified on a 2D Gel are usually attributable to one protein. If the identity of the protein is desired, the gel spot can be excised, and digested proteolytically. The peptide masses resulting from the digestion can be determined by mass spectrometry using peptide mass fingerprinting. If this information does not allow unequivocal identification of the protein, its peptides can be subject to tandem mass spectrometry. Characterization of protein mixtures using HPLC/MS is also called shotgun proteomics and mudpit. A peptide mixture that results from digestion of a protein mixture is fractionated by one or two steps of liquid chromatography. The eluent from the chromatography stage can be either directly introduced to the mass spectrometer through electrospray ionization, or laid down on a series of small spots for later mass analysis using MALDI.

Protein identification

There are two main ways MS is used to identify proteins. Peptide mass fingerprinting (mentioned in the previous section) uses the masses of proteolytic peptides as input to a search of a database of predicted masses that would arise from digestion of a list of known proteins. If a protein sequence in the reference list gives rise to a significant number of predicted masses that match the experimental values, there is some evidence that this protein was present in the original sample. Tandem MS is becoming a more popular experimental method for identifying proteins. Collision-induced dissociation is used in mainstream applications to generate a set of fragments from a specific peptide ion. The fragmentation process primarily gives rise to cleavage products that break along peptide bonds. Because of this simplicity in fragmentation, it is possible to use the observed fragment masses to match with a database of predicted masses for one of many given peptide sequences. Tandem MS of whole protein ions has been investigated recently using electron capture dissociation and has demonstrated extensive sequence information in principle but is not in common practice. This is sometimes referred to as the "top-down" approach in that it involves starting with the whole mass and then pulling it apart rather than starting with pieces (proteolytic fragments) and piecing the protein back together using De novo repeat detection (bottom-up).

History

The first mass spectrography technique was described in an 1899 article by English scientist J.J. Thomson. The processes that more directly gave rise to the modern version were devised by Arthur Jeffrey Dempster and F.W. Aston in 1918 and 1919 respectively. In 2002, the Nobel Prize in Chemistry was received by John Fenn for the development of electrospray ionization (ESI) and Koichi Tanaka for the development of soft laser desorption (SLD) in 1987. An improved SLD method, matrix-assisted laser desorption/ionization (MALDI), was developed by Franz Hillenkamp and Michael Karas in 1988. The choice of Tanaka to recieve the nobel prize for this work over Hillenkamp and Karas is a contentious issue to some people in the field. The two methodologies are remarkably similiar yet significantly different. The work of Hillenkamp and Karas is fundamentally the same as the current implementation of matrix-assisted laser desorption/ionization which is now ubiqitous in mass spectrometry. Hillenkamp and Karas also demonstrated exceptionally well the importance of this new technique. On the other hand the work of Tanaka is similar and published significantly earlier such that the work of Hillenkamp and Karas could in theory be a derivative improvement. Yet, the work of Tanaka on SLD may have never come to prominence or become particularly useful without futher improvement.

External links

- [http://www.asms.org/ American Society for Mass Spectrometry]
- [http://www.latrobe.edu.au/anzsms/ Australian and New Zealand Society for Mass Spectrometry]
- [http://www.bmss.org.uk/ British Mass Spectrometry Society]
- [http://www.csms.inter.ab.ca/ Canadian Society for Mass Spectrometry]
- [http://www.imss.nl/ International Mass Spectrometry Society]
- [http://masspec.scripps.edu/information/history/ A History of Mass Spectrometry (Scripps)]
- [http://www.vias.org/simulations/simusoft_msscope.html Mass spectrometer simulation] An interactive application simulating the console of a mass spectrometer
- [http://www.msterms.com/wiki/ Mass spectrometry terms wiki]
- [http://www.chem.arizona.edu/quizplease/msintro/aldehyd/aldehyd.htm#begin Self-test]

References

- McLafferty, F. W. and Turecek, F., Interpretation of Mass Spectra, University Science Books; 4th edition (May, 1993) ISBN 0935702253 Category:Mass spectrometry Category:Measuring instruments ja:質量分析法

Ion

: This article is about the electrically charged particle. For other uses of this word, see ion (disambiguation). An ion is an atom or group of atoms with a net electric charge. A negatively charged ion, which has more electrons in its electron shell than it has protons in its nucleus, is known as an anion, for it is attracted to anodes, and a positively charged ion, which has fewer electrons than protons, is known as a cation (pronounced cat-eye-on), for it is attracted to cathodes. The process of converting into ions and the state of being ionized is called ionization. The recombining of ions and electrons to form neutral atoms is called recombination. Polyatomic anions which contain oxygen are sometimes known as oxyanion. Atomic and polyatomic ions are denoted by a superscript with the sign of the net electric charge and the number of electrons lost or gained, if more than one. For example: H⁺, S O₃²⁻. A collection of non-aqueous ions, or even a gas containing a proportion of charged particles, is called a plasma, which is called the fourth state of matter because its properties are quite different from solids, liquids, and gases.

Ionization potential

The energy required to detach an electron in its lowest energy state from an atom or molecule of a gas with less net electric charge is called the ionization potential, or ionization energy. The nth ionization energy of an atom is the energy required to detach its nth electron after the first n − 1 electrons have already been detached. Each successive ionization energy is markedly greater than the last. Particularly great increases occur after any given block of atomic orbitals is exhausted of electrons. For this reason, ions tend to form in ways that leave them with full orbital blocks. For example, sodium has one valence electron, in its outermost shell, so in ionized form it is commonly found with one lost electron, as Na⁺. On the other side of the periodic table, chlorine has seven valence electrons, so in ionized form it is commonly found with one gained electron, as Cl⁻. Francium has the lowest ionization energy of all the elements and fluorine has the greatest.

Other ions

A dianion is a species which has two negative charges on it. For example, the dianion of pentalene is aromatic. A zwitterion is an ion with a net charge of zero, but has both a positive and negative charge on it.

History

Ions were first theorized by Michael Faraday around 1830, to describe the portions of molecules that travel either to an anode or to a cathode. However, the mechanism by which this was achieved was not described until 1884 by Svante August Arrhenius in his doctoral dissertation to the University of Uppsala. His theory was initially not accepted but his dissertation won the Nobel Prize in Chemistry in 1903.

Etymology

The word ion is a name given by Michael Faraday, from Greek , neutral present participle of , "to go", thus "a goer". So, anion, , and cation, κ, mean "(a thing) going up" and "(a thing) going down", respectively, and anode, , and cathode, κ, mean "a going up" and "a going down", respectively, from , "way".

Applications

Ions are essential to life. Sodium, potassium, calcium and other ions play an important role in the cells of living organisms, particularly in cell membranes. They have many practical, everyday applications in items such as smoke detectors and are also finding use in unconventional technologies such as ion engines and ion cannons. Category:Physical chemistry ko:이온 ms:Ion ja:イオン simple:Ion th:ไอออน

Mass spectrometer

How it works in layman terms

F=ma

Instrumentation

Ion source

Mass analyzer

\mathbf
  = q (\mathbf + \mathbf \times \mathbf),

a>b

Detector

Hyphenated MS

Gas chromatography/MS

Liquid chromatography/MS

IMS/MS

Tandem MS (MS/MS)

Applications

Isotope ratio MS

Trace Gas Analysis

Pharmcokinetics

Mass spectrometry of proteins

Protein and peptide fractionation coupled with mass spectrometry

Protein identification

History

External links

References

University of Munster

The University of Münster (German Westfälische Wilhelms-Universität Münster, WWU) is a public university located in the city of Münster, North Rhine-Westphalia in Germany. With more than 40,000 students and above [http://zsb.uni-muenster.de/studium_wwu/faecherliste.php 130 fields of study] in 2004 it is one of Germany's largest universities and one of the foremost centers of German intellectual life. The University of Münster is an internationally renowned university.

History

The University has its roots in the Jesuiten-Kolleg Münster, which was founded in 1588. But the today known University of Münster was founded in 1780 with four faculties: Law, Health Science (Medicine), Philosophy and Theology. The ceremony of constitution was performed by Franz Freiherr von Fürstenberg. In 1805 the university was extended to the Prussian University of Westphalia. It got its current name from Emperor Wilhelm II in 1907: Westfälische Wilhelms-Universität (WWU).

Organisation

- Faculty of Protestant Theology
- Faculty of Catholic Theology
- Faculty of Law
- Faculty of Economics (Muenster School of Business Administration and Economics)
- Faculty of Health Science (Medicine and Dental Medicine)
- Faculty of Philosophy
- Faculty of Educational and Social Science
- Faculty of Psychology and Sport Science
- Faculty of History/Philosophy
- Faculty of Philology
- Faculty of Natural Science and Mathematics
- Faculty of Mathematics and Computer Science
- Faculty of Physics
- Faculty of Chemistry and Pharmacy
- Faculty of Biology
- Faculty of Earth Science
- Faculty of Music (Muenster School of Music)

Research

Every department (they are different in size and staff) has its own research projects, the following items are inter-department research projects:
- Biotechnology
- Graduate School: Molecular basis of dynamic cellular processes
- [http://www.mpi-muenster.mpg.de/ Max-Planck-Institut] - Max-Planck-Department for molecular biomedical science
- Business and Economics
- See Muenster School of Business Administration and Economics
- Chemistry
- [http://www.uni-muenster.de/GSC-MS/site/index.html Graduate School of Chemistry]
- European Graduate School: Template Directed Chemical Synthesis
- German-Japanese Graduate School: Complex Functional Systems in Chemistry: Design, Development and Applications
- Education
- International Research Center for Talents
- History
- Graduate School: Symbols in the Middle Ages
- Information Systems and Business Computer Science
- [http://www.ercis.de/ European Research Center for Information Systems (ERCIS)]
- Mathematics
- Graduate School: Analytical Topology and Meta Geometry
- Graduate School: Non-Linear Systems
- Physics
- [http://www.centech.de Center for Nanotechnology]
- Political Science
- [http://www.uni-muenster.de/GraSP/ Graduate School of Politics]
- Psychology
- Virtual Graduate School (list is not complete)

Notable alumni

Students

- Wolfgang Clement, Politician
- Gabriele Behler, Politician
- Prof. Dr. Hans-Jürgen Ewers, Economist
- Prof. Dr. Dieter Fenske, Chemist
- Birgit Fischer, Politician
- Erich Gutenberg, Economist
- Wolf-Michael Catenhusen, Politician
- Dr. Dr. Gustav Heinemann, Politician
- Prof. Dr. Dr. h.c. mult. Friedrich Hirzebruch, Mathematician
- Jens Lehmann, Soccerplayer (goal keeper) of the German Soccer Team
- Dr. Thomas Middelhoff, Board of Directors Bertelsmann
- Prof. Dr. Georg Milbradt, Prime Minister of Saxony
- Walter Momper, Politician
- Ruprecht Polenz, Politician
- Prof. Dr. Dr. Gerhard Roth, Neurobiology
- Dr. Winfried Scharlau, Journalist
- Dr. Kurt Schumacher, Politician
- Dr. h.c. Rudolf Seiters, Politician
- Burkhard Spinnen, Author
- Prof. Dr. Dr. h.c.mult. Hans Tietmeyer, Economist
- Dr. Berthold Tillmann, Politician
- Klaus Töpfer, UNO-Commissar
- Ernst Tugendhat, Philosopher
- Arthur Wieferich, Mathematician
- Dr. Klaus Zumwinkel, Board of Directors Deutsche Post World Net

Nobel Prize

- Johannes Georg Bednorz, Nobel prize winner (1987)

Fields Medal

- Prof. Dr. Gerd Faltings, Mathematician (list not complete)

University lecturer

- Pope Benedict XVI: Prof. Dr. Dr. h. c. mult. Joseph Kardinal Ratzinger
- Prof. Dr. Wolfgang Metzger, Psychologist (list not complete)

Honorary Doctor

- Prof. Dr. Dr. h.c. Jan Assmann (D. theol. h.c. Faculty of Proestant Theology (1998))
- Prof. Dr. Dr. h.c. Arnold L. Demain, Biotechnology (2003 Department of Biology, Faculty of Natural Science and Mathematics)
- Prof. Dr. Dr. h.c. Ernst-Wolfgang Böckenförde, Judge, Bundesverfassungsgericht (2001 Faculty of Law)
- Prof. Dr. Dr. h.c. David A. O. Edward, Judge (2001 Faculty of Law)
- Prof. Dr. h.c. Gilberto Freyre Ph.D.
- Dr. h.c. Mikhail Gorbachev
- Dr. h.c. Manfred Gotthardt (2003 Faculty of Health Science (Medicine))
- Prof. Dr. Dr. h.c. Tomas Hammar, Political Scientist (2002 Faculty of Philosophie)
- Dr. h.c. Wim Kok, Prime Minister (Netherlands) (2003 Faculty of Philosophie)
- Dr. h.c. Hanna-Renate Laurien, Theologian (1996 Faculty of Catholic Theology)
- Prof. Dr. Dr. h.c. Robert Leicht, Reporter (2003 Faculty of Protestant Theology)
- Dr. h.c. Reinhard Mohn, Director Bertelsmann (2001 Faculty of Economics (Münster School of Business Administration and Economics))
- Dr. h.c. Rupert Neudeck
- Dr. h.c. Jean-Claude Juncker, Prime Minister (Luxembourg)
- Prof. Dr. Dr. h.c. Hubert Schmidbaur, Chemist (2005 Department of Chemistry and Pharmacy, Faculty of Natural Science and Mathematics)
- Dr. h.c. Erich Schumann, Jurist (2002 Faculty of Law)
- Dr. h.c. Wolfgang Thierse, Politician (list not complete)

External link

- [http://www.uni-muenster.de/en/ University of Münster (English)]
- [http://www.uni-muenster.de/en/research/ University of Münster Research (English)]
- [http://www.uni-muenster.de/Alumni/en/ University of Münster Alumni (English)] Muenster ja:ミュンスター大学

University of Munster

History

Organisation

Research

Notable alumni

Students

Nobel Prize

- Johannes Georg Bednorz, Nobel prize winner (1987)

Fields Medal

- Prof. Dr. Gerd Faltings, Mathematician (list not complete)

University lecturer

- Pope Benedict XVI: Prof. Dr. Dr. h. c. mult. Joseph Kardinal Ratzinger
- Prof. Dr. Wolfgang Metzger, Psychologist (list not complete)

Honorary Doctor

External link

Geozentrische Breite

Als geozentrische Breite (ψ) wird in den Geowissenschaften jene Breite bezeichnet, die der Ortsvektor vom Erdmittelpunkt zum Festpunkt an der Erdoberfläche mit der Äquatorebene einschließt. Die geografische Breite (mit B, ß oder φ bezeichnet) ist hingegen um bis zu 0,19 Grad größer, weil sie sich auf die Lotrichtung beziehungsweise Normale zum Erdellipsoid bezieht. Letztere geht nicht durch das Erdzentrum, sondern läuft daran um bis zu 20 km vorbei. Siehe auch: Ellipse, Erdabplattung, Geozentrisch, Geografie, kartesische Koordinaten

Weblinks

- [http://www.ottmarlabonde.de/L1/datum_beispiele.html Unterschied zwischen Geozentrische Breite und Geografische Breite] Kategorie:Geodäsie

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2000 Midland is located at 44°4'16" North, 101°9'23" West (44.071134, -101.156336). According to the United States Census Bureau, the town has a total area of 0.9