関連する実験動画

Updated: Jul 11, 2026

Measuring Carbon-based Contaminant Mineralization Using Combined CO2 Flux and Radiocarbon Analyses
11:19

Measuring Carbon-based Contaminant Mineralization Using Combined CO2 Flux and Radiocarbon Analyses

Published on: October 21, 2016

太陽斑・オーロラ・ソーラー・インデックスの相対的な大気中の炭素14の活動の変化

J R Bray

    Science (New York, N.Y.)
    |May 5, 1967
    PubMed
    まとめ

    放射性炭素の活動は太陽の活動と正反対に相関しており,炭素14は以前の太陽周期からの汚染により,より信頼性の低い太陽指数である可能性があることを示唆しています.

    さらに関連する動画

    Measurement of Aerosols Optical Thickness of the Atmosphere using the GLOBE Handheld Sun Photometer06:27

    Measurement of Aerosols Optical Thickness of the Atmosphere using the GLOBE Handheld Sun Photometer

    Published on: May 29, 2019

    Scattering And Absorption of Light in Planetary Regoliths11:34

    Scattering And Absorption of Light in Planetary Regoliths

    Published on: July 1, 2019

    関連する概念動画

    Factors Affecting Activity Coefficient01:17

    Factors Affecting Activity Coefficient

    The extended Debye-Hückel equation indicates that the activity coefficient of an ion in an aqueous solution at 25°C depends on three partially interdependent properties: the ionic strength of the solution, the charge of the ion, and the ion size. 
    The activity coefficient value for an ion is close to one when the solution has almost zero ionic strength, i.e., when the solution shows close to ideal behavior. As the ionic strength of the solution increases from 0 to 0.1 mol/L, a decrease in the...
    Radioactive Decay and Radiometric Dating02:48

    Radioactive Decay and Radiometric Dating

    Radioactivity is a spontaneous disintegration of an unstable nuclide and is a random process, as all the nuclei in the sample do not decay simultaneously. The number of disintegrations per unit time is called the activity (A), which is directly proportional to the number of nuclei in the sample. The decay constant (λ) is an average probability of decay per nucleus in unit time.
    Carbon-13 (¹³C) NMR: Overview01:10

    Carbon-13 (¹³C) NMR: Overview

    Carbon-13 is a naturally occurring NMR-active isotope of carbon with a low natural abundance of 1.1%. In contrast, carbon-12 is the most abundant isotope of carbon with zero nuclear spin. Therefore, it is NMR inactive. The gyromagnetic ratio of carbon-13 is smaller than that of protons. As a result, carbon-13 resonance is about 6000 times weaker than proton resonance. For a given magnetic field strength, the resonance frequency of carbon-13 is about one-fourth of the resonance frequency for...
    Variation of Atmospheric Pressure01:18

    Variation of Atmospheric Pressure

    Change in atmospheric pressure with height is particularly interesting. The decrease in atmospheric pressure with increasing altitude is due to the decreasing gravitational force per unit area as we move away from the surface of the earth.
    Assuming the air temperature is constant at a given altitude and that the ideal gas law of thermodynamics describes the atmosphere to a good approximation, one can find the variation of atmospheric pressure with height.
    Let p(y) be the atmospheric pressure at...
    Thermodynamics: Activity Coefficient01:24

    Thermodynamics: Activity Coefficient

    Activity is the measure of the effective concentration of the species in solution. It can be expressed as the product of the molar concentration of the species and its activity coefficient. The activity coefficient is a dimensionless quantity and depends on the total ionic strength of the solution.
    The activity coefficient is a measure of the deviation from ideal behavior. When the ionic strength of the solution is minimal, the activity coefficient of an ionic species is close to unity, making...
    Arrhenius Plots02:34

    Arrhenius Plots

    The Arrhenius equation relates the activation energy and the rate constant, k, for chemical reactions. In the Arrhenius equation, k = Ae−Ea/RT, R is the ideal gas constant, which has a value of 8.314 J/mol·K, T is the temperature on the kelvin scale, Ea is the activation energy in J/mole, e is the constant 2.7183, and A is a constant called the frequency factor, which is related to the frequency of collisions and the orientation of the reacting molecules.
    The Arrhenius equation can be used to...