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  2. Ytterbium - Wikipedia

    en.wikipedia.org/wiki/Ytterbium

    Neoytterbia later became known as the element ytterbium, and lutecia became known as the element lutetium. The Austrian chemist Carl Auer von Welsbach independently isolated these elements from ytterbia at about the same time, but he called them aldebaranium ( Ad ; after Aldebaran ) and cassiopeium ; [ 13 ] the American chemist Charles James ...

  3. List of gases - Wikipedia

    en.wikipedia.org/wiki/List_of_gases

    This list is sorted by boiling point of gases in ascending order, but can be sorted on different values. "sub" and "triple" refer to the sublimation point and the triple point, which are given in the case of a substance that sublimes at 1 atm; "dec" refers to decomposition. "~" means approximately.

  4. Greenhouse effect - Wikipedia

    en.wikipedia.org/wiki/Greenhouse_effect

    Most gases whose molecules have two different atoms (such as carbon monoxide, CO), and all gases with three or more atoms (including H 2 O and CO 2), are infrared active and act as greenhouse gases. (Technically, this is because when these molecules vibrate , those vibrations modify the molecular dipole moment , or asymmetry in the distribution ...

  5. Greenhouse gas emissions - Wikipedia

    en.wikipedia.org/wiki/Greenhouse_gas_emissions

    Greenhouse gas emissions in 2019 were estimated at 57.4 GtCO 2 e, while CO 2 emissions alone made up 42.5 Gt including land-use change (LUC). [ 94 ] While mitigation measures for decarbonization are essential on the longer term, they could result in weak near-term warming because sources of carbon emissions often also co-emit air pollution .

  6. Emission spectrum - Wikipedia

    en.wikipedia.org/wiki/Emission_spectrum

    An emission spectrum is formed when an excited gas is viewed directly through a spectroscope. Schematic diagram of spontaneous emission Emission spectroscopy is a spectroscopic technique which examines the wavelengths of photons emitted by atoms or molecules during their transition from an excited state to a lower energy state.

  7. Thermionic emission - Wikipedia

    en.wikipedia.org/wiki/Thermionic_emission

    Typically made of a mixture of barium, strontium and calcium oxides, the coating is sputtered away through normal use, eventually resulting in lamp failure. Thermionic emission is the liberation of charged particles from a hot electrode whose thermal energy gives some particles enough kinetic energy to escape the material's surface.

  8. Black carbon - Wikipedia

    en.wikipedia.org/wiki/Black_carbon

    "Emissions of black carbon are the second strongest contribution to current global warming, after carbon dioxide emissions". [5] Calculation of black carbon's combined climate forcing at 1.0–1.2 W/m 2 , which "is as much as 55% of the CO 2 forcing and is larger than the forcing due to the other [GHGs] such as CH 4 , CFCs, N 2 O or ...

  9. Atomic emission spectroscopy - Wikipedia

    en.wikipedia.org/wiki/Atomic_emission_spectroscopy

    Plasma is a collection of charged particles (cations and electrons) capable, by virtue of their charge, of interacting with a magnetic field. The plasmas used in atomic emissions are formed by ionizing a flowing stream of argon gas. Plasma's high-temperature results from resistive heating as the charged particles move through the gas.