146.137.70.71: typo: interpretablity -> interpretability

2014-08-01T15:40:34Z

typo: interpretablity -> interpretability

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	~~The writer~~ is ~~known as Wilber Pegues~~. ~~Her family lives~~ in ~~Ohio but~~ her ~~spouse desires them to transfer~~. Credit authorising is ~~where my main earnings comes from. One of the extremely very best things in the globe for him is doing ballet and he'll be beginning something else alongside with it~~.<br><br>My blog post ~~:: certified psychics~~ ([http://~~cspl.postech~~.ac.~~kr/zboard/Membersonly/144571 http:~~//~~cspl.postech.ac~~.~~kr/~~])		Hi there, I am Sophia. To perform lacross is the thing I love most of all. Some time in the past she chose to live in Alaska and her mothers and fathers reside nearby. Credit authorising is how she tends to make a residing.<br><br>Check out my blog post ... psychic readings ([http://Www.Familysurvivalgroup.com/easy-methods-planting-looking-backyard/ familysurvivalgroup.com])

en>Qwertyus: /* Estimation */ math formatting

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en>Fgnievinski: /* See also */

2013-10-23T06:34:37Z

See also

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	~~Hi there~~. ~~Let me begin~~ by ~~introducing~~ the ~~author~~, ~~her~~ title is ~~Sophia~~. ~~He works~~ as a ~~bookkeeper~~. ~~For years he~~'~~s been living~~ in ~~Alaska and he doesn~~'~~t strategy on altering it~~. ~~What~~ I ~~love doing~~ is ~~football but I don't have~~ the ~~time recently~~.<br><br>~~Feel free~~ to ~~surf~~ to ~~my weblog psychic phone readings;~~ [~~https~~://~~www~~.~~machlitim~~.~~org~~.il/~~subdomain~~/~~megila~~/~~end~~/~~node~~/~~12300 visit this site right here~~],		{{Use dmy dates\|date=November 2012}}
			'''Gas phase ion chemistry''' is a field of science encompassed within both [[chemistry]] and [[physics]]. It is the science that studies [[ion]]s and [[molecule]]s in the gas phase, most often enabled by some form of [[mass spectrometry]]. By far the most important applications for this science is in studying the [[thermodynamic]]s and [[chemical kinetics\|kinetics]] of reactions.<ref name=Aubry2000>{{Cite journal \| last = Aubry \| first = C. \| year = 2000 \| title = Correlating thermochemical data for gas-phase ion chemistry \| journal = International Journal of Mass Spectrometry \| volume = 200 \| issue = 1-3 \| pages = 277 \| doi = 10.1016/S1387-3806(00)00323-7 \| postscript = <!--None-->}}</ref><ref>[http://www.iupac.org/publications/pac/1998/pdf/7010x1969.pdf Pure & Appl. Chem., Vol. 70, No. 10, pp. 1969-1976, 1998.]</ref> For example one application is in studying the [[thermodynamics]] of the [[solvation]] of ions. Ions with small [[solvation]] spheres of 1, 2, 3... solvent molecules can be studied in the gas phase and then extrapolated to bulk solution.

			==Theory==

			===Transition state theory===
			{{Main\|Transition state theory}}
			Transition state theory is the theory of the rates of elementary reactions which assumes a special type of [[chemical equilibrium]] (quasi-equilibrium) between reactants and activated complexes.<ref>{{GoldBookRef\|title=Transition State Theory\|file= T06470}}</ref>

			===RRKM theory===
			{{main\|RRKM theory}}
			RRKM theory is used to compute simple estimates of the [[unimolecular ion decomposition]] [[reaction rates]] from a few characteristics of the [[potential energy surface]].

			==Gas phase ion formation==
			The process of converting an [[atom]] or [[molecule]] into an [[ion]] by adding or removing charged particles such as [[electron]]s or other ions can occur in the gas phase. These processes are an important component of gas phase ion chemistry.

			===Associative ionization===
			{{main\|Associative ionization}}
			Associative ionization is a gas phase reaction in which two [[atom]]s or [[molecule]]s interact to form a single product [[ion]].<ref>{{GoldBookRef\|title=associative ionization\|file= A00475}}</ref>

			:<math>A^* + B \to AB^{+\bullet} + e^-</math>

			where species A with excess internal energy (indicated by the asterisk) interacts with B to form the ion AB<sup>+</sup>.

			One or both of the interacting species may have excess [[internal energy]].

			===Charge-exchange ionization===
			{{main\|Charge-exchange ionization}}
			Charge-exchange ionization (also called '''charge-transfer ionization''') is a gas phase reaction between an [[ion]] and a neutral species
			:<math>A^+ + B \to A + B^+</math>
			in which the charge of the ion is transferred to the neutral.<ref>{{GoldBookRef\|title=charge-exchange ionization\|file= C00989}}</ref>

			===Chemical ionization===
			{{main\|chemical ionization}}
			In chemical ionization, ions are produced through the reaction of ions of a reagent gas with other species.<ref>Munson, M.S.B.; Field, F.H. ''J. Am. Chem. Soc.'' '''1966''', ''88'', 2621-2630. [http://dx.doi.org/10.1021/ja00964a001 Chemical Ionization Mass Spectrometry. I. General Introduction].</ref> Some common reagent gases include: [[methane]], [[ammonia]], and [[isobutane]].

			===Chemi-ionization===
			{{main\|Chemi-ionization}}
			Chemi-ionization can be represented by
			:<math>G^* + M \to M^{+\bullet} + e^- + G</math>
			where G is the excited state species (indicated by the superscripted asterisk), and M is the species that is ionized by the loss of an [[electron]] to form the [[Radical (chemistry)\|radical]] [[cation]] (indicated by the superscripted "plus-dot").

			===Penning ionization===
			{{main\|Penning ionization}}
			Penning ionization refers to the interaction between a gas-phase excited-state atom or molecule G<sup>*</sup> and a target molecule M resulting in the formation of a radical molecular cation M<sup>+.</sup>, an electron e<sup>−</sup>, and a neutral gas molecule G:<ref>{{GoldBookRef\|title=Penning gas mixture\|file= P04476}}</ref>

			:<math>G^* + M \to M^{+\bullet} + e^- + G</math>

			Penning ionization occurs when the target molecule has an [[ionization potential]] lower than the internal energy of the excited-state atom or molecule. [[associative ionization\|Associative]] Penning ionization can also occur:

			:<math>G^* + M \to MG^{+\bullet} + e^-</math>

			==Fragmentation==
			There are many important [[Dissociation (chemistry)\|dissociation]] reactions that take place in the gas phase.

			===Collision-induced dissociation===
			{{main\|Collision-induced dissociation}}
			CID (also called collisionally activated dissociation - CAD) is a method used to fragment molecular [[ion]]s in the gas phase.<ref name="pmid16401509">{{cite journal \|author=Wells JM, [[Scott A. McLuckey\|McLuckey SA]] \|title=Collision-induced dissociation (CID) of peptides and proteins \|journal=Meth. Enzymol. \|volume=402 \|issue= \|pages=148–85 \|year=2005 \|pmid=16401509 \|doi=10.1016/S0076-6879(05)02005-7}}</ref><ref name="pmid15481084">{{cite journal \|author=Sleno L, Volmer DA \|title=Ion activation methods for tandem mass spectrometry \|journal=Journal of mass spectrometry : JMS \|volume=39 \|issue=10 \|pages=1091–112 \|year=2004 \|pmid=15481084 \|doi=10.1002/jms.703}}</ref> The molecular ions collide with neutral gas molecules such as [[helium]], [[nitrogen]] or [[argon]]. In the collision some of the kinetic energy is converted into [[internal energy]] which results in fragmentation.

			===Charge remote fragmentation===
			{{main\|Charge remote fragmentation}}
			Charge remote fragmentation is a type of [[covalent bond]] breaking that occurs in a gas phase [[ion]] in which the cleaved bond is not adjacent to the location of the charge.<ref name="pmid11199379">{{cite journal \|author=Cheng C, Gross ML \|title=Applications and mechanisms of charge-remote fragmentation \|journal=Mass Spectrom Rev \|volume=19 \|issue=6 \|pages=398–420 \|year=2000 \|pmid=11199379 \|doi=10.1002/1098-2787(2000)19:6<398::AID-MAS3>3.0.CO;2-B}}</ref><ref name=Gross2000>{{Cite journal \| last = Gross \| first = M. \| year = 2000 \| title = Charge-remote fragmentation: an account of research on mechanisms and applications \| journal = International Journal of Mass Spectrometry \| volume = 200 \| issue = 1-3 \| pages = 611 \| doi = 10.1016/S1387-3806(00)00372-9 \| postscript = <!--None--> }}</ref>

			==Charge transfer reactions==
			There are several types of charge-transfer reactions<ref>{{GoldBookRef\|title=charge-transfer reaction (in mass spectrometry)\|file=C01005}}</ref> (also known as charge-permutation reactions<ref>{{GoldBookRef\|title=charge-permutation reaction\|file=M04002}}</ref>): partial-charge transfer

			:<math>A^{2+} + B \to A^+ + B^+</math>,

			charge-stripping reaction<ref>{{GoldBookRef\|title=charge-stripping reaction\|file=C01001}}</ref>

			:<math>A^+ + B \to A^{2+} + B + e^-</math>,

			and charge-inversion reaction<ref>{{GoldBookRef\|title=charge-inversion mass spectrum\|file=C00992}}</ref> positive to negative

			:<math>A^+ + B \to A^- + B^{2+} </math>

			and negative to positive

			:<math>A^- + B \to A^+ + B + 2e^-</math>.

			==See also==
			*[[Adiabatic ionization]]
			*[[Mass-analyzed ion kinetic energy spectrometry]]
			*[[Plasma (physics)]]
			*[[Michael T. Bowers]]
			*[[R. Graham Cooks]]
			*[[Helmut Schwarz]]

			== References ==
			{{Reflist}}

			==Bibliography==
			{{refbegin}}
			*Fundamentals of gas phase ion chemistry, Keith R. Jennings (ed.), Dordrecht, Boston, Kluwer Academic, 1991, pp. 226-8
			*Gas Phase Ion Chemistry, Michael T. Bowers, ed., Academic Press, New York, 1979
			*Gas Phase Ion Chemistry Vol 2.; Bowers, M.T., Ed.; Academic Press: New York, 1979
			*Gas Phase Ion Chemistry Vol 3., Michael T. Bowers, ed., Academic Press, New York, 1983
			{{refend}}

			==External links==
			* http://webbook.nist.gov/chemistry/ion/

			[[Category:Mass spectrometry]]

en>Melcombe: revise cats

2012-05-31T20:28:45Z

revise cats

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Hi there. Let me begin by introducing the author, her title is Sophia. He works as a bookkeeper. For years he's been living in Alaska and he doesn't strategy on altering it. What I love doing is football but I don't have the time recently.<br><br>Feel free to surf to my weblog psychic phone readings; [https://www.machlitim.org.il/subdomain/megila/end/node/12300 visit this site right here],

Generalized additive model - Revision history

146.137.70.71: typo: interpretablity -> interpretability

en>Qwertyus: /* Estimation */ math formatting

en>Fgnievinski: /* See also */

en>Melcombe: revise cats