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  2. Diffusion-limited aggregation - Wikipedia

    en.wikipedia.org/wiki/Diffusion-limited_aggregation

    Diffusion-limited aggregation (DLA) is the process whereby particles undergoing a random walk due to Brownian motion cluster together to form aggregates of such particles. . This theory, proposed by T.A. Witten Jr. and L.M. Sander in 1981, [1] is applicable to aggregation in any system where diffusion is the primary means of transport in the sy

  3. Atmospheric-pressure chemical ionization - Wikipedia

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

    For example, when methanol solvent is present, the cluster solvent ions would be CH 3 OH 2 + (H 2 O) n (CH 3 OH) m. [2] Fragmentation does not normally occur inside the APCI source. If a fragment ion of a sample is observed, thermal degradation has taken place by the heated nebulizer interface, followed by the ionization of the decomposition ...

  4. 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 ...

  5. Adduct - Wikipedia

    en.wikipedia.org/wiki/Adduct

    A good example from solid-state chemistry is the adducts of ethylene or carbon monoxide of CuAlCl 4. The latter is a solid with an extended lattice structure. Upon formation of the adduct, a new extended phase is formed in which the gas molecules are incorporated (inserted) as ligands of the copper atoms within the

  6. Atmospheric-pressure photoionization - Wikipedia

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

    Molecules are ionized using a vacuum ultraviolet (VUV) light source operating at atmospheric pressure (105 Pa), either by direct absorption followed by electron ejection or through ionization of a dopant molecule that leads to chemical ionization of target molecules. The sample is usually a solvent spray that is vaporized by nebulization and heat.

  7. Mesoscale convective system - Wikipedia

    en.wikipedia.org/wiki/Mesoscale_convective_system

    A shelf cloud, such as this one, can be a sign that a squall is imminent.. A mesoscale convective system (MCS) is a complex of thunderstorms that becomes organized on a scale larger than the individual thunderstorms but smaller than extratropical cyclones, and normally persists for several hours or more.

  8. Michael addition reaction - Wikipedia

    en.wikipedia.org/wiki/Michael_Addition_Reaction

    For example, the image below shows the addition of ethylmagnesium bromide to ethyl sorbate 1 using a copper catalyst with a reversed josiphos (R,S)-(–)-3 ligand. [35] This reaction produced the 1,6-addition product 2 in 0% yield, the 1,6-addition product 3 in approximately 99% yield, and the 1,4-addition product 4 in less than 2% yield.

  9. Cycloaddition - Wikipedia

    en.wikipedia.org/wiki/Cycloaddition

    For example, an analog for the Diels-Alder reaction is the quadricyclane-DMAD reaction: In the (i+j+...) cycloaddition notation i and j refer to the number of atoms involved in the cycloaddition. In this notation, a Diels-Alder reaction is a (4+2)cycloaddition and a 1,3-dipolar addition such as the first step in ozonolysis is a (3+2)cycloaddition.