| 词条 | Chlorine-37 |
| 释义 |
|background = #999999 |isotope_name = Chlorine-37 |num_neutrons = 20 |num_protons = 17 |isotope_filename = |alternate_names = |mass_number=37 |abundance = 24.23% |symbol=Cl |decay_product = None |halflife=Stable |error_halflife = |mass= |mass number=37 |excess_energy = |error1 = |binding_energy = |error2 = |spin = |decay_mode1= |decay_energy1= }}Chlorine-37 (37Cl), is one of the stable isotopes of chlorine, the other being chlorine-35 ({{SimpleNuclide|Chlorine|35}}). Its nucleus contains 17 protons and 20 neutrons for a total of 37 nucleons. Chlorine-37 accounts for 24.23% of natural chlorine, chlorine-35 accounting for 75.77%, giving chlorine atoms in bulk an apparent atomic weight of {{val|35.453|(2)|u=g/mol}}.[1] Remarkably, solar neutrinos were discovered by an experiment using a radiochemical method based on chlorine-37 transmutation.[2] Neutrino detection{{Main|Homestake experiment}}One of the historically important radiochemical methods of solar neutrino detection is based on inverse electron capture triggered by the absorption of an electron neutrino.[3] Chlorine-37 transmutes into argon-37 via the reaction[4] {{SimpleNuclide|Chlorine|37}} + {{Subatomic particle|Electron neutrino}} → {{SimpleNuclide|Argon|37}} + {{Subatomic particle|Electron-}}. Argon-37 then de-excites itself via electron capture (half-life = 35 d) into chlorine-37 via the reaction {{SimpleNuclide|Argon|37}} + {{Subatomic particle|Electron-}} → {{SimpleNuclide|Chlorine|37}} + {{Subatomic particle|Electron neutrino}}. These last reactions involve Auger electrons of specific energies.[3][5] The detection of these electrons confirms that a neutrino event took place. Detection methods involve several hundred thousand liters of carbon tetrachloride (CCl4) or tetrachloroethylene (C2Cl4) stored in underground tanks.[2][3][6] OccurrenceThe representative terrestrial abundance of chlorine-37 is 24.22(4)% of chlorine atoms,[7] with a normal range of 24.14–24.36% of chlorine atoms. When measuring deviations in isotopic composition, the usual reference point is "Standard Mean Ocean Chloride" (SMOC), although a NIST Standard Reference Material (975a) also exists. SMOC is known to be around 24.219% chlorine-37 and to have an atomic weight of around 35.4525[8] There is a known variation in the isotopic abundance of chlorine-37. This heavier isotope tends to be more prevalent in chloride minerals than in aqueous solutions such as sea water, although the isotopic composition of organochlorine compounds can vary in either direction from the SMOC standard in the range of several parts per thousand.[8] See also
References1. ^{{AtWt 2005}} 2. ^1 {{cite journal|doi=10.1038/scientificamerican0769-28|author=J.N. Bahcall|title=Neutrinos from the Sun|url=http://www.sns.ias.edu/~jnb/Papers/Popular/Scientificamerican69/scientificamerican69.html|journal = Scientific American|volume = 221 |issue = 1 |year = 1969|pages=28–37|bibcode=1969SciAm.221a..28B}} 3. ^1 2 {{cite book|last=Sutton|first=Christine|title=Spaceship Neutrino|url=https://books.google.com/books?id=JBOdejRrmaMC&pg=PA151&lpg=PA151&dq=chlorine-37+neutrino|publisher=Cambridge University Press|pages=151–152|year=1992|isbn=978-0-521-36404-1|oclc=25246163}} 4. ^{{cite book|author=F.H. Shu|title=The Physical Universe: An Introduction to Astronomy|url=https://books.google.com/books?id=v_6PbAfapSAC&pg=PA122&lpg=PA122&dq=chlorine+37+neutrino|publisher=University Science Books|page=122|year=1982|isbn=978-0-935702-05-7}} 5. ^{{cite journal|author=A.H. Snell, F. Pleasonton|title=Spectrometry of the Neutrino Recoils of Argon-37|journal=Physical Review|volume=100 |issue=5 |pages=1396–1403|year=1955|doi=10.1103/PhysRev.100.1396|bibcode = 1955PhRv..100.1396S}} 6. ^{{cite book|author = A. Bhatnagar, W. Livingston|title = Fundamental of Solar Astronomy|url = https://books.google.com/books?id=fe7XDuxCYjcC&pg=PA88&lpg=PA88&dq=chlorine+37+neutrino|publisher=World Scientific|pages=87–89|year=2005|isbn=978-981-238-244-3}} 7. ^{{AtWt TICE 1997}} 8. ^1 {{AtWt Rev 2000}} 1 : Isotopes of chlorine |
| 随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。