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  2. Land change modeling - Wikipedia

    en.wikipedia.org/wiki/Land_change_modeling

    Land change modeling has a variety of implementation opportunities in many science and practice disciplines, such as in decision-making, policy, and in real-world application in public and private domains. Land change modeling is a key component of land change science, which uses LCMs to assess long-term outcomes for land cover and climate. The ...

  3. Direct analysis in real time - Wikipedia

    en.wikipedia.org/wiki/Direct_analysis_in_real_time

    In mass spectrometry, direct analysis in real time (DART) is an ion source that produces electronically or vibronically excited-state species from gases such as helium, argon, or nitrogen that ionize atmospheric molecules or dopant molecules. The ions generated from atmospheric or dopant molecules undergo ion-molecule reactions with the sample ...

  4. Adduct - Wikipedia

    en.wikipedia.org/wiki/Adduct

    A good example is the formation of adducts between the Lewis acid borane and the oxygen atom in the Lewis bases, tetrahydrofuran (THF): BH 3 ·O(CH 2) 4 or diethyl ether: BH 3 ·O(CH 3 CH 2) 2. Many Lewis acids and Lewis bases reacting in the gas phase or in non-aqueous solvents to form adducts have been examined in the ECW model. [3]

  5. Atmospheric-pressure chemical ionization - Wikipedia

    en.wikipedia.org/wiki/Atmospheric-pressure...

    Atmospheric pressure chemical ionization chamber cross section. Atmospheric pressure chemical ionization (APCI) is an ionization method used in mass spectrometry which utilizes gas-phase ion-molecule reactions at atmospheric pressure (10 5 Pa), [1] [2] commonly coupled with high-performance liquid chromatography (HPLC). [3]

  6. Electrospray ionization - Wikipedia

    en.wikipedia.org/wiki/Electrospray_ionization

    Electrospray (nanoSpray) ionization source. Electrospray ionization (ESI) is a technique used in mass spectrometry to produce ions using an electrospray in which a high voltage is applied to a liquid to create an aerosol.

  7. Mass spectrometry - Wikipedia

    en.wikipedia.org/wiki/Mass_spectrometry

    Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions.The results are presented as a mass spectrum, a plot of intensity as a function of the mass-to-charge ratio.

  8. Spin trapping - Wikipedia

    en.wikipedia.org/wiki/Spin_trapping

    The spin adduct usually yields a distinctive EPR spectrum characteristic of a particular free radical that is trapped. The identity of the radical can be inferred based on the EPR spectral profile of their respective spin adducts such as the g value, but most importantly, the hyperfine-coupling constants of relevant nuclei. Unambiguous ...

  9. Aldol reaction - Wikipedia

    en.wikipedia.org/wiki/Aldol_reaction

    Anti adducts, which require an E enolate, cannot be obtained reliably with the Evans method. However, Z enolates, leading to syn adducts, can be reliably formed using boron-mediated soft enolization: [32] Often, a single diastereomer may be obtained by one crystallization of the aldol adduct. Many methods cleave the auxiliary: [33]