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  2. Predicting the timing of peak oil - Wikipedia

    en.wikipedia.org/wiki/Predicting_the_timing_of...

    This was critiqued by K. Aleklett and M. Höök, but their critique has itself been accused of bias towards non-representative depletion rates, with the result that their figures are ill-founded. [62] Subsequent research clarified more on depletion rates and different ways to define them, but still showed that it rests on solid scientific ...

  3. Time-resolved spectroscopy - Wikipedia

    en.wikipedia.org/wiki/Time-resolved_spectroscopy

    In physics and physical chemistry, time-resolved spectroscopy is the study of dynamic processes in materials or chemical compounds by means of spectroscopic techniques.Most often, processes are studied after the illumination of a material occurs, but in principle, the technique can be applied to any process that leads to a change in properties of a material.

  4. Asymmetric hydrogenation - Wikipedia

    en.wikipedia.org/wiki/Asymmetric_hydrogenation

    Iron is a popular research target for many catalytic processes, owing largely to its low cost and low toxicity relative to other transition metals. [18] Asymmetric hydrogenation methods using iron have been realized, although in terms of rates and selectivity, they are inferior to catalysts based on precious metals. [19]

  5. Stopped-flow - Wikipedia

    en.wikipedia.org/wiki/Stopped-flow

    The stopped-flow method evolved from the continuous-flow technique developed by Hamilton Hartridge and Francis Roughton [7] to study the binding of oxygen to hemoglobin. In the continuous-flow system, the reaction mixture was passed through a long tube, past an observation system (a simple colorimeter in 1923), and then discarded as waste.

  6. Enantioselective synthesis - Wikipedia

    en.wikipedia.org/wiki/Enantioselective_synthesis

    Enantioselective synthesis, also called asymmetric synthesis, [1] is a form of chemical synthesis.It is defined by IUPAC as "a chemical reaction (or reaction sequence) in which one or more new elements of chirality are formed in a substrate molecule and which produces the stereoisomeric (enantiomeric or diastereomeric) products in unequal amounts."

  7. Dynamic kinetic resolution in asymmetric synthesis - Wikipedia

    en.wikipedia.org/wiki/Dynamic_Kinetic_Resolution...

    Asymmetric synthesis has become a much explored field due to the challenge of creating a compound with a single 3D structure. [1] Even more challenging is the ability to take a racemic mixture and have only one chiral product left after a reaction. One method that has become an exceedingly useful tool is dynamic kinetic resolution (DKR).

  8. Asymmetric flow field flow fractionation - Wikipedia

    en.wikipedia.org/wiki/Asymmetric_flow_field_flow...

    AF4 and other FFF methods have been extensively used in environmental research on the impact of nano materials [2] and to characterize condensed tannins oxidation. [3] For high molar mass and branched polymers, AF4 has been shown to achieve good separation, whereas SEC fails, [4] and AF4 has been applied to polyolefines at temperatures above ...

  9. Sharpless asymmetric dihydroxylation - Wikipedia

    en.wikipedia.org/wiki/Sharpless_asymmetric_di...

    K. Barry Sharpless was the first to develop a general, reliable enantioselective alkene dihydroxylation, referred to as the Sharpless asymmetric dihydroxylation (SAD). Low levels of OsO 4 are combined with a stoichiometric ferricyanide oxidant in the presence of chiral nitrogenous ligands to create an asymmetric environment around the oxidant.