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Updated: Jul 28, 2025

Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
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电子冲击散射对伊米达的理论研究

Tejas Jani1,2, Vinodkumar P C3, Minaxi Vinodkumar2

  • 1Gujarat Arts & Science College, Gujarat University, Ahmedabad 38006, India.

The journal of physical chemistry. A
|May 31, 2023
PubMed
概括

对伊米达的电子散射计算揭示了对其生物化学过程的新见解. 这项研究证实了已知的共振,并报告了新的截面,增强了我们对电子与这种医学相关分子相互作用的理解.

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Chemical Ionization (CI) Mass Spectrometry

The molecular ion peak of a molecule in the mass spectrum provides vital information for molecular identification. However, conventional electron impact ionization can lead to the rapid dissociation of some molecular ions before they reach the detector. A milder ionization method is required to increase the lifetime of such ionized analyte molecules. Chemical ionization (CI) is a gas-phase protonation reaction useful for mass-analyzing analyte molecules that are easily protonated to yield the...
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π Electron Effects on Chemical Shift: Overview

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The protons in unsubstituted alkanes are strongly shielded with chemical shifts below 1.8 ppm. Methine, methylene, and methyl protons appear at approximately 1.7, 1.2 and 0.7 ppm, while the proton signal from methane appears at 0.23 ppm. An electronegative substituent, such as chlorine, withdraws the electron density from the protons, increasing their chemical shift. Progressive substitution of the hydrogens in methane by chlorine shifts the proton signals increasingly downfield, to 3.05 ppm in...
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