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{{redirect|Carbon-15|the firearm|Carbon 15}}
Golda is what's created on my beginning certificate even though it is not the name on my beginning certification. My day job is an invoicing officer but I've already applied for another one. The preferred pastime for him and his kids is style and he'll be starting some thing else along with it. Her family members life in Ohio.<br><br>my blog [http://black7.mireene.com/aqw/5741 clairvoyance]
'''[[Carbon]]''' ('''C''') has 15 known [[isotope]]s, from <sup>8</sup>C to <sup>22</sup>C, 2 of which ([[Carbon-12|<sup>12</sup>C]] and [[Carbon-13|<sup>13</sup>C]]) are stable. The longest-lived radioisotope is [[Carbon-14|<sup>14</sup>C]], with a [[half-life]] of 5,700 years. This is also the only carbon radioisotope found in nature - trace quantities are formed [[cosmogenic]]ally by the reaction <sup>14</sup>N + <sup>1</sup>n → <sup>14</sup>C + <sup>1</sup>H. The most stable artificial radioisotope is <sup>11</sup>C, which has a half-life of 20.334 minutes. All other radioisotopes have half-lives under 20 seconds, most less than 200 milliseconds. The least stable isotope is <sup>8</sup>C, with a half-life of 2.0&nbsp;x&nbsp;10<sup>−21</sup>&nbsp;s. Averaging over natural abundances, the standard atomic mass for carbon is 12.0107(8) [[unified atomic mass unit|u]].
 
==Carbon-11==
'''Carbon-11''' or '''<sup>11</sup>C''' is a radioactive isotope of [[carbon]] that decays to [[boron-11]]. This decay mainly occurs due to [[positron emission]]; however, around 0.19-0.23% of the time, it is a result of [[electron capture]].<ref name=c11>{{cite journal|last=Scobie|first=J.|coauthors=Lewis, G. M.|title=K-capture in carbon 11|journal=Philosophical Magazine|date=1 September 1957|volume=2|issue=21|pages=1089–1099|doi=10.1080/14786435708242737|url=http://www.tandfonline.com/doi/abs/10.1080/14786435708242737#preview|accessdate=27 March 2012|bibcode = 1957PMag....2.1089S }}</ref><ref name=c11-2>{{cite journal|last=Campbell|first=J.L.|coauthors=Leiper, W., Ledingham, K.W.D., Drever, R.W.P.|title=The ratio of K-capture to positon emission in the decay of 11C|journal=Nuclear Physics A|volume=96|issue=2|pages=279–287|doi=10.1016/0375-9474(67)90712-9|url=http://www.sciencedirect.com/science/article/pii/0375947467907129|accessdate=27 March 2012|bibcode = 1967NuPhA..96..279C }}</ref> It has a [[half-life]] of 20.334 minutes.<!--I have amended this to agree with figure quoted in earlier paragraph; if 20.38 is correct, then please also amend earlier reference-->
 
:{{SimpleNuclide|Carbon|11}} &rarr; {{SimpleNuclide|link|Boron|11}} + {{SubatomicParticle|link=yes|positron}} + {{SubatomicParticle|link=yes|Electron neutrino}} + {{Val|0.96|ul=MeV}}
:{{SimpleNuclide|Carbon|11}} + {{SubatomicParticle|link=yes|Electron}} &rarr; {{SimpleNuclide|link|Boron|11}} + {{SubatomicParticle|link=yes|Electron neutrino}} + {{Val|3.17|ul=MeV}}
 
Carbon-11 is commonly used as a [[radioisotope]] for the radioactive labeling of molecules in [[positron emission tomography]]. Among the many molecules used in this context is the [[radioligand]] [[DASB|[{{SimpleNuclide|Carbon|11}}]DASB]].
 
==Natural isotopes==
{{main|Carbon-12|Carbon-13|Carbon-14}}
There are three naturally occurring [[isotopes]] of carbon: 12, 13, and 14. <sup>12</sup>C and <sup>13</sup>C are stable, occurring in a natural proportion of approximately 99:1. <sup>14</sup>C is produced by thermal neutrons from cosmic radiation in the upper atmosphere, and is transported down to earth to be absorbed by living biological material. Isotopically, <sup>14</sup>C constitutes a negligible part; but, since it is radioactive with a half-life of 5,700 years, it is radiometrically detectable. Since dead tissue doesn't absorb <sup>14</sup>C, the amount of <sup>14</sup>C is one of the methods used within the field of archeology for [[radiometric dating]] of biological material.
 
== Paleoclimate ==
 
<sup>12</sup>C and <sup>13</sup>C are measured as the [[Isotope analysis#Stable isotope analysis in aquatic ecosystems|isotope ratio]] δ<sup>13</sup>C in [[benthic]] [[foraminifera]] and used as a [[proxy (climate)|proxy]] for [[nutrient cycling]] and the temperature dependent air-sea exchange of CO<sub>2</sub> (ventilation) (Lynch-Stieglitz et al., 1995). Plants find it easier to use the lighter isotopes (<sup>12</sup>C) when they convert sunlight and carbon dioxide into food. So, for example, large blooms of [[plankton]] (free-floating organisms) absorb large amounts of <sup>12</sup>C from the oceans. Originally, the <sup>12</sup>C was mostly incorporated into the seawater from the atmosphere. If the oceans that the plankton live in are stratified (meaning that there are layers of warm water near the top, and colder water deeper down), then the surface water does not mix very much with the deeper waters, so that when the plankton dies, it sinks and takes away <sup>12</sup>C from the surface, leaving the surface layers relatively rich in <sup>13</sup>C. Where cold waters well up from the depths (such as in the North Atlantic), the water carries <sup>12</sup>C back up with it. So, when the ocean was less stratified than today, there was much more <sup>12</sup>C in the skeletons of surface-dwelling species. Other indicators of past climate include the presence of tropical species, coral growths rings, etc.<ref>[[Tim Flannery]] ''The weather makers: the history & future of climate change'', The Text Publishing Company, Melbourne, Australia. ISBN 1-920885-84-6</ref>
 
==Tracing food sources and diets==
The quantities of the different isotopes can be measured by [[mass spectrometry]] and compared to a standard; the result (e.g. the delta of the <sup>13</sup>C = δ<sup>13</sup>C) is expressed as parts per thousand (‰).
 
:<math>\delta ^{13}C = \Biggl( \frac{\bigl( \frac{^{13}C}{^{12}C} \bigr)_{sample}}{\bigl( \frac{^{13}C}{^{12}C} \bigr)_{standard}} -1 \Biggr) * 1000\ ^{o}\!/\!_{oo}</math>
 
Stable carbon isotopes in [[carbon dioxide]] are utilized differentially by plants during [[photosynthesis]]. Grasses in [[temperate climate]]s ([[barley]], [[rice]], [[wheat]], [[rye]] and [[oats]], plus [[sunflower]], [[potato]], [[tomato]]es, [[peanut]]s, [[cotton]], [[sugar beet]], and most trees and their nuts/fruits, [[rose]]s and [[Kentucky bluegrass]]) follow a [[C3 carbon fixation|C3 photosynthetic pathway]] that will yield δ<sup>13</sup>C values averaging about −26.5‰. Grasses in hot [[arid climate]]s ([[maize]] in particular, but also [[millet]], [[sorghum]], [[sugar cane]] and [[crabgrass]]) follow a [[C4 carbon fixation|C4 photosynthetic pathway]] that produces δ<sup>13</sup>C values averaging about −12.5‰.
 
It follows that eating these different plants will affect the δ<sup>13</sup>C values in the consumer’s body tissues. If an animal (or human) eats only C3 plants, their δ<sup>13</sup>C values will be −12.5‰ in their bone [[collagen]] and −14.5‰ in their [[apatite]].<ref>Tycot, R.H. (2004) “Stable isotopes and diet: you are what you eat.” Proceedings of the International School of Physics ‘Enrico Fermi’Course CLIV, edited by M. Martini, M. Milazzo and M. Piacentini. Amsterdam: IOS Press.</ref>
 
In contrast, C4 feeders will have bone collagen with a value of −7.5‰ and apatite value of −0.5‰.
 
In actual case studies, millet and maize eaters can easily be distinguished from rice and wheat eaters. Studying how these dietary preferences are distributed geographically through time can illuminate migration paths of people and dispersal paths of different agricultural crops. However, human groups have often mixed C3 and C4 plants (northern Chinese historically subsisted on wheat and millet), or mixed plant and animal groups together (for example, southeastern Chinese subsisting on rice and fish).<ref>{{cite journal | author = Hedges Richard | year = 2006 | title = Where does our protein come from? | url = | journal = British Journal of Nutrition | volume = 95 | issue = | pages = 1031–2 }}</ref>
 
== Table ==
{| class="wikitable" style="font-size:95%; white-space:nowrap"
! nuclide<br />symbol
! Z([[proton|p]])
! N([[neutron|n]])
! &nbsp;<br />isotopic mass (u)<br />&nbsp;
! half-life
! decay mode(s)<ref>http://www.nucleonica.net/unc.aspx</ref>
! daughter<br>isotope(s)<ref group="n">Bold for stable isotopes</ref>
! nuclear<br />spin
! representative<br />isotopic<br />composition<br />(mole fraction)
! range of natural<br />variation<br />(mole fraction)
|-
| <sup>8</sup>C
| style="text-align:right" | 6
| style="text-align:right" | 2
| 8.037675(25)
| 2.0(4) × 10<sup>−21</sup> s<br>[230(50) keV]
| [[proton emission|2p]]
| {{SimpleNuclide|Beryllium|6}}<ref group="n">Subsequently decays by double proton emission to '''<sup>4</sup>He''' for a net reaction of <sup>8</sup>C -> '''<sup>4</sup>He''' + 4'''<sup>1</sup>H'''</ref>
| 0+
|
|
|-
| rowspan=3|<sup>9</sup>C
| rowspan=3 style="text-align:right" | 6
| rowspan=3 style="text-align:right" | 3
| rowspan=3|9.0310367(23)
| rowspan=3|126.5(9) ms
| [[Beta decay|β<sup>+</sup>]] (60%)
| {{SimpleNuclide|Boron|9}}<ref group="n">Immediately decays by proton emission to <sup>8</sup>Be, which immediately decays to two '''<sup>4</sup>He''' atoms for a net reaction of <sup>9</sup>C -> 2'''<sup>4</sup>He''' + '''<sup>1</sup>H''' + e<sup>+</sup></ref>
| rowspan=3|(3/2-)
| rowspan=3|
| rowspan=3|
|-
| β<sup>+</sup>, p (23%)
| {{SimpleNuclide|Beryllium|8}}<ref group="n">Immediately decays into two '''<sup>4</sup>He''' atoms for a net reaction of <sup>9</sup>C -> 2'''<sup>4</sup>He''' + '''<sup>1</sup>H''' + e<sup>+</sup></ref>
|-
| β<sup>+</sup>, [[alpha decay|α]] (17%)
| {{SimpleNuclide|Lithium|5}}<ref group="n">Immediately decays by proton emission to '''<sup>4</sup>He''' for a net reaction of <sup>9</sup>C -> 2'''<sup>4</sup>He''' + '''<sup>1</sup>H''' + e<sup>+</sup></ref>
|-
| <sup>10</sup>C
| style="text-align:right" | 6
| style="text-align:right" | 4
| 10.0168532(4)
| 19.290(12) s
| β<sup>+</sup>
| '''{{SimpleNuclide|Boron|10}}'''
| 0+
|
|
|-
| rowspan=2|<sup>11</sup>C<ref group="n">Used for labeling molecules in [[positron emission tomography|PET scans]]</ref>
| rowspan=2 style="text-align:right" | 6
| rowspan=2 style="text-align:right" | 5
| rowspan=2 |11.0114336(10)
| rowspan=2 |20.334(24) min
| β<sup>+</sup> (99.79%)
| '''{{SimpleNuclide|Boron|11}}'''
| rowspan=2 |3/2-
| rowspan=2 |
| rowspan=2 |
|-
| [[Electron capture|K-capture]] (.21%)<ref name=c11/><ref name=c11-2/>
| '''{{SimpleNuclide|Boron|11}}'''
|-
| [[Carbon-12|<sup>12</sup>C]]
| style="text-align:right" | 6
| style="text-align:right" | 6
| 12 exactly<ref group="n">The [[unified atomic mass unit]] is defined as 1/12 the mass of an unbound atom of carbon-12 at ground state</ref>
| colspan=3 align=center|'''Stable'''
| 0+
| 0.9893(8)
| 0.98853-0.99037
|-
| [[Carbon-13|<sup>13</sup>C]]<ref group="n">[[δ13C|Ratio of <sup>12</sup>C to <sup>13</sup>C]] used to measure biological productivity in ancient times and differing types of [[photosynthesis]]</ref>
| style="text-align:right" | 6
| style="text-align:right" | 7
| 13.0033548378(10)
| colspan=3 align=center|'''Stable'''
| 1/2-
| 0.0107(8)
| 0.00963-0.01147
|-
| [[Carbon-14|<sup>14</sup>C]]<ref group="n">Has an important use in [[radiodating]] (see [[carbon dating]])</ref>
| style="text-align:right" | 6
| style="text-align:right" | 8
| 14.003241989(4)
| 5,730 years
| β<sup>−</sup>
| '''{{SimpleNuclide|Nitrogen|14}}'''
| 0+
| Trace<ref group="n">Primarily [[cosmogenic]], produced by [[neutron]]s striking atoms of [[Nitrogen-14|<sup>14</sup>N]] (<sup>14</sup>N + <sup>1</sup>n -> <sup>14</sup>C + <sup>1</sup>H)</ref>
| <10<sup>−12</sup>
|-
| <sup>15</sup>C
| style="text-align:right" | 6
| style="text-align:right" | 9
| 15.0105993(9)
| 2.449(5) s
| β<sup>−</sup>
| '''{{SimpleNuclide|Nitrogen|15}}'''
| 1/2+
|
|
|-
| rowspan=2|<sup>16</sup>C
| rowspan=2 style="text-align:right" | 6
| rowspan=2 style="text-align:right" | 10
| rowspan=2|16.014701(4)
| rowspan=2|0.747(8) s
| β<sup>−</sup>, [[neutron emission|n]] (97.9%)
| '''{{SimpleNuclide|Nitrogen|15}}'''
| rowspan=2|0+
| rowspan=2|
| rowspan=2|
|-
| β<sup>−</sup> (2.1%)
| {{SimpleNuclide|Nitrogen|16}}
|-
| rowspan=2|<sup>17</sup>C
| rowspan=2 style="text-align:right" | 6
| rowspan=2 style="text-align:right" | 11
| rowspan=2|17.022586(19)
| rowspan=2|193(5) ms
| β<sup>−</sup> (71.59%)
| {{SimpleNuclide|Nitrogen|17}}
| rowspan=2|(3/2+)
| rowspan=2|
| rowspan=2|
|-
| β<sup>−</sup>, n (28.41%)
| {{SimpleNuclide|Nitrogen|16}}
|-
| rowspan=2|<sup>18</sup>C
| rowspan=2 style="text-align:right" | 6
| rowspan=2 style="text-align:right" | 12
| rowspan=2|18.02676(3)
| rowspan=2|92(2) ms
| β<sup>−</sup> (68.5%)
| {{SimpleNuclide|Nitrogen|18}}
| rowspan=2|0+
| rowspan=2|
| rowspan=2|
|-
| β<sup>−</sup>, n (31.5%)
| {{SimpleNuclide|Nitrogen|17}}
|-
| rowspan=3|<sup>19</sup>C<ref group="n">Has 1 [[halo nucleus|halo]] neutron</ref>
| rowspan=3 style="text-align:right" | 6
| rowspan=3 style="text-align:right" | 13
| rowspan=3|19.03481(11)
| rowspan=3|46.2(23) ms
| β<sup>−</sup>, n (47.0%)
| {{SimpleNuclide|Nitrogen|18}}
| rowspan=3|(1/2+)
| rowspan=3|
| rowspan=3|
|-
| β<sup>−</sup> (46.0%)
| {{SimpleNuclide|Nitrogen|19}}
|-
| β<sup>−</sup>, 2n (7%)
| {{SimpleNuclide|Nitrogen|17}}
|-
| rowspan=2|<sup>20</sup>C
| rowspan=2 style="text-align:right" | 6
| rowspan=2 style="text-align:right" | 14
| rowspan=2|20.04032(26)
| rowspan=2|16(3) ms<br>[14(+6-5) ms]
| β<sup>−</sup>, n (72.0%)
| {{SimpleNuclide|Nitrogen|19}}
| rowspan=2|0+
| rowspan=2|
| rowspan=2|
|-
| β<sup>−</sup> (28.0%)
| {{SimpleNuclide|Nitrogen|20}}
|-
| <sup>21</sup>C
| style="text-align:right" | 6
| style="text-align:right" | 15
| 21.04934(54)#
| <30 ns
| n
| {{SimpleNuclide|Carbon|20}}
| (1/2+)#
|
|
|-
| <sup>22</sup>C<ref group="n">Has 2 halo neutrons</ref>
| style="text-align:right" | 6
| style="text-align:right" | 16
| 22.05720(97)#
| 6.2(13) ms<br>[6.1(+14-12) ms]
| β<sup>−</sup>
| {{SimpleNuclide|Nitrogen|22}}
| 0+
|
|
|}
 
<references group="n" />
 
=== Notes ===
* The precision of the isotope abundances and atomic mass is limited through variations. The given ranges should be applicable to any normal terrestrial material.
* Values marked # are not purely derived from experimental data, but at least partly from systematic trends. Spins with weak assignment arguments are enclosed in parentheses.
* Uncertainties are given in concise form in parentheses after the corresponding last digits. Uncertainty values denote one standard deviation, except isotopic composition and standard atomic mass from IUPAC which use expanded uncertainties.
* Carbon-12 nuclide is of particular importance as it is used as the standard from which atomic masses of all nuclides are expressed: its atomic mass is by definition 12 Da.
* Nuclide masses are given by [[IUPAP]] Commission on Symbols, Units, Nomenclature, Atomic Masses and Fundamental Constants (SUNAMCO).
* Isotope abundances are given by [[IUPAC]] [[Commission on Isotopic Abundances and Atomic Weights]].
 
==See also==
* [[radiocarbon dating]]
* [[Cosmogenic isotope]]s
* [[Environmental isotopes]]
* [[Isotopic signature]]
 
== References ==
<references/>
* Isotope masses from:
**{{cite journal |author=G. Audi, A. H. Wapstra, C. Thibault, J. Blachot and O. Bersillon |year=2003 |title=The NUBASE evaluation of nuclear and decay properties |url=http://www.nndc.bnl.gov/amdc/nubase/Nubase2003.pdf |journal=[[Nuclear Physics A]] |volume=729 |issue= |pages=3–128 |doi=10.1016/j.nuclphysa.2003.11.001 |bibcode=2003NuPhA.729....3A}}
* Isotopic compositions and standard atomic masses from:
**{{cite journal |author=J. R. de Laeter, J. K. Böhlke, P. De Bièvre, H. Hidaka, H. S. Peiser, K. J. R. Rosman and P. D. P. Taylor |year=2003 |title=Atomic weights of the elements. Review 2000 (IUPAC Technical Report) |url=http://www.iupac.org/publications/pac/75/6/0683/pdf/ |journal=[[Pure and Applied Chemistry]] |volume=75 |issue=6 |pages=683–800 |doi=10.1351/pac200375060683}}
**{{cite journal |author=M. E. Wieser |year=2006 |title=Atomic weights of the elements 2005 (IUPAC Technical Report) |url=http://iupac.org/publications/pac/78/11/2051/pdf/ |journal=[[Pure and Applied Chemistry]] |volume=78 |issue=11 |pages=2051–2066 |doi=10.1351/pac200678112051 |laysummary=http://old.iupac.org/news/archives/2005/atomic-weights_revised05.html}}
* Half-life, spin, and isomer data selected from the following sources. See editing notes on [[Talk:Isotopes of carbon|this article's talk page]].
**{{cite journal |author=G. Audi, A. H. Wapstra, C. Thibault, J. Blachot and O. Bersillon |year=2003 |title=The NUBASE evaluation of nuclear and decay properties |url=http://www.nndc.bnl.gov/amdc/nubase/Nubase2003.pdf |journal=[[Nuclear Physics A]] |volume=729 |issue= |pages=3–128 |doi=10.1016/j.nuclphysa.2003.11.001 |bibcode=2003NuPhA.729....3A}}
**{{cite web |author=[[National Nuclear Data Center]] |year= |title=NuDat 2.1 database |url=http://www.nndc.bnl.gov/nudat2/ |publisher=[[Brookhaven National Laboratory]] |accessdate=September 2005}}
**{{cite book |author=N. E. Holden |year=2004 |editor=D. R. Lide |chapter=Table of the Isotopes |title=[[CRC Handbook of Chemistry and Physics]] |page=Section 11 |nopp=yes |edition=85th |publisher=[[CRC Press]] |isbn=978-0-8493-0485-9}}
 
{{Isotope nav | element=carbon | lighter=Isotopes of boron | heavier=Isotopes of nitrogen }}
 
[[Category:Carbon]]
[[Category:Isotopes of carbon| ]]
[[Category:Lists of isotopes by element|Carbon]]

Latest revision as of 18:55, 30 November 2014

Golda is what's created on my beginning certificate even though it is not the name on my beginning certification. My day job is an invoicing officer but I've already applied for another one. The preferred pastime for him and his kids is style and he'll be starting some thing else along with it. Her family members life in Ohio.

my blog clairvoyance

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