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  2. Clar's rule - Wikipedia

    en.wikipedia.org/wiki/Clar's_rule

    Clar's rule states that for a benzenoid polycyclic aromatic hydrocarbon (i.e. one with only hexagonal rings), the resonance structure with the largest number of disjoint aromatic π-sextets is the most important to characterize its chemical and physical properties.

  3. Polycyclic aromatic hydrocarbon - Wikipedia

    en.wikipedia.org/wiki/Polycyclic_aromatic...

    According to Clar's rule, [20] the resonance structure of a PAH that has the largest number of disjoint aromatic pi sextets—i.e. benzene-like moieties—is the most important for the characterization of the properties of that PAH. [21] Benzene-substructure resonance analysis for Clar's rule

  4. Acoustic resonance spectroscopy - Wikipedia

    en.wikipedia.org/wiki/Acoustic_resonance...

    Acoustic resonance spectroscopy (ARS) is a method of spectroscopy in the acoustic region, primarily the sonic and ultrasonic regions. ARS is typically much more rapid than HPLC and NIR . It is non destructive and requires no sample preparation as the sampling waveguide can simply be pushed into a sample powder/liquid or in contact with a solid ...

  5. Nuclear acoustic resonance - Wikipedia

    en.wikipedia.org/wiki/Nuclear_Acoustic_Resonance

    Nuclear acoustic resonance is a phenomenon closely related to nuclear magnetic resonance. It involves utilizing ultrasound and ultrasonic acoustic waves of frequencies between 1 MHz and 100 MHz to determine the acoustic radiation resulted from interactions of particles that experience nuclear spins as a result of magnetic and/or electric fields ...

  6. Nuclear reaction analysis - Wikipedia

    en.wikipedia.org/wiki/Nuclear_reaction_analysis

    with a sharp resonance in the reaction cross section at 6.385 MeV of only 1.8 keV. [3] Since the incident 15 N ion loses energy along its trajectory in the material it must have an energy higher than the resonance energy to induce the nuclear reaction with hydrogen nuclei deeper in the target.

  7. Swain–Lupton equation - Wikipedia

    en.wikipedia.org/wiki/Swain–Lupton_equation

    A linear least-squares analysis is used to determine the coefficients/constants a, b, and i (Swain and Lupton used a procedure called DOVE: Dual Obligate Vector Evaluation). [2] Constants were first based on three previous reactions (σ m , σ p , σ p+ ), which leads to more possible errors since the compiled data is only a minimal combination ...

  8. US FDA tightens scrutiny of lab-developed tests with new rule

    www.aol.com/news/us-fda-publishes-final-rule...

    (Reuters) -The U.S. Food and Drug Administration (FDA) on Monday tightened regulations for clinical laboratories with a new rule that gives it more oversight of diagnostic tests developed by them.

  9. Erich Clar - Wikipedia

    en.wikipedia.org/wiki/Erich_Clar

    Erich Clar (23 August 1902 – 27 March 1987) was an Austrian organic chemist, born in HÅ™ensko, who studied polycyclic aromatic hydrocarbon chemistry. He is considered as the father of that field. [ 1 ]