太陽系外部のデウテリウム:二つの異なる貯蔵庫の証拠
1Department of Earth and Space Sciences, State University of New York at Stony Brook 11794, USA.
Nature
|March 20, 1986
まとめ
科学者たちは土星,タイタン,ウラノスのデウテリウムとメタンの比率を測定した. 発見は,太陽系より前に形成された2つの原始的なデウテリウム貯蔵庫を示唆しています: 1つはガスで,もう1つは冷たい固体に閉じ込められています.
科学分野:
- 惑星科学は惑星科学である.
- アストロケミストリー アストロケミストリー
- 太陽系形成 太陽系形成について
背景:
- 惑星の大気中のデウテリウム (水素の重い同位体) の豊富さは,初期の太陽系に関する手がかりを提供します.
- 以前の研究では,デュテリウム貯蔵庫の変動が示されましたが,包括的な理解は欠けています.
研究 の 目的:
- 土星,タイタン,天王星の大気中のCH3D/CH4比率を決定する.
- 太陽系における原始デュテリウム貯蔵庫に対するこれらの比率の影響を調査する.
主な方法:
- 土星,タイタン,天王星からの大気サンプルを光譜分析.
- 新たに得られたCH3D/CH4比の比較と,他の天体からの既存のデータ.
主要な成果:
- 土星,タイタン,天王星のCH3D/CH4比の測定は成功裏に完了しました.
- この結果は,以前の研究と組み合わせて,少なくとも2つの異なる原始デュテリウム貯蔵庫の存在を示しています.
- これらの貯蔵庫は,冷たい固体物質に閉じ込められたガス状の水素と揮発性物質として識別されます.
結論:
- 太陽系のデウテリウムは,それが形成される前に少なくとも2つの別々の貯水池に確立されました.
- 1つの貯蔵庫は,ガス状水素中のデウテリウムで構成されています.
- 2つ目の貯蔵庫は,低温で保存された揮発性物質の内部にあるデウテリウム,または氷のような水素から分離されたデウテリウムを含んでいる.
さらに関連する動画
09:00Electrochemical Detection of Deuterium Kinetic Isotope Effect on Extracellular Electron Transport in Shewanella oneidensis MR-1
Published on: April 16, 2018
08:22Using Deuterium Oxide as a Non-Invasive, Non-Lethal Tool for Assessing Body Composition and Water Consumption in Mammals
Published on: February 20, 2020
関連する概念動画
Hess's Law
There are two ways to determine the amount of heat involved in a chemical change: measure it experimentally, or calculate it from other experimentally determined enthalpy changes. Some reactions are difficult, if not impossible, to investigate and make accurate measurements for experimentally. And even when a reaction is not hard to perform or measure, it is convenient to be able to determine the heat involved in a reaction without having to perform an experiment.
The Pauli Exclusion Principle
The arrangement of electrons in the orbitals of an atom is called its electron configuration. We describe an electron configuration with a symbol that contains three pieces of information:
¹H NMR of Labile Protons: Deuterium (²H) Substitution
This lesson illustrates the role of deuterium substitution in simplifying the NMR spectrum of compounds comprising labile protons. One method employed is the use of deuterium. Amongst the three isotopes of hydrogen, deuterium (2H) has a nucleus composed of one proton and one neutron. When the D2O solvent is added to a pure dry ethanol solution, its labile proton is substituted with deuterium.
Detection of Black Holes
Although black holes were theoretically postulated in the 1920s, they remained outside the domain of observational astronomy until the 1970s.
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
Their closest cousins are neutron stars, which are composed almost entirely of neutrons packed against each other, making them extremely dense. A neutron star has the same mass as the Sun but its diameter is only a few kilometers. Therefore, the escape velocity from their surface is close to the speed of light.
Not until the 1960s, when the first neutron...
¹³C NMR: ¹H–¹³C Decoupling
The probability of having two carbon-13 atoms next to each other is negligible because of the low natural abundance of carbon-13. Consequently, peak splitting due to carbon-carbon spin-spin coupling is not observed in spectra. However, protons up to three sigma bonds away split the carbon signal according to the n+1 rule, resulting in complicated spectra.
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
A broadband decoupling technique is used to simplify these complex, sometimes overlapping, signals. Broadband decoupling relies on a...
Chemical Shift: Internal References and Solvent Effects
In an NMR sample, precise measurement of the absolute absorption frequencies of nuclei is difficult. A standard internal reference compound is added, and the frequency difference between the reference signal and sample signals is measured.
The internal reference compound generally used in NMR spectroscopy is tetramethylsilane (TMS). TMS is preferred because it is chemically inert, soluble in NMR solvents, and easily removable. Also, the highly shielded methyl protons in TMS yield an intense...
The internal reference compound generally used in NMR spectroscopy is tetramethylsilane (TMS). TMS is preferred because it is chemically inert, soluble in NMR solvents, and easily removable. Also, the highly shielded methyl protons in TMS yield an intense...
