Kinetic shift in chlorobenzene ion fragmentation and the heat of formation of the phenyl ion

The process of nonlinear resonant excitation of ion oscillations in a linear trap is studied. There is still no detailed simulation of the resonance peak in the literature. We propose to use the excitation contour to describe the collective ion resonance. The excitation contour is a resonant mass peak obtained by the trajectory method with the Gaussian distribution of the initial coordinates and velocities. The following factors are considered: excitation time, low order hexapole and octopole harmonics with amplitudes A3 and A4, the depth of the initial ion cloud position. These multipoles are used for selective ion ejection from linear ion trap. All these factors affect the ion yield and the shape of the contours. Obtained data can be useful for control of such processes as ion fragmentation, ion isolation, ion activation, and ion ejection. Simulated resonance peaks are important for the theoretical description of the ion collective nonlinear resonances.

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Reactions of the benzyne radical anion in the gas phase, the acidity of the phenyl radical, and the heat of formation of o-benzyne

Journal of the American Chemical Society ◽

10.1021/ja00016a001 ◽

1991 ◽

Vol 113 (16) ◽

pp. 5923-5931 ◽

Cited By ~ 48

Author(s):

Yili Guo ◽

Joseph J. Grabowski

Keyword(s):

Gas Phase ◽

Radical Anion ◽

Heat Of Formation ◽

Phenyl Radical

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Boron-Decorated Pillared Graphene as the Basic Element for Supercapacitors: An Ab Initio Study

Applied Sciences ◽

10.3390/app11083496 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3496

Author(s):

Dmitry A. Kolosov ◽

Olga E. Glukhova

Keyword(s):

Density Functional ◽

Dft Method ◽

Heat Of Formation ◽

Basic Element ◽

Supercapacitor Electrode ◽

Functional Theory ◽

Icosahedral Clusters ◽

New Material ◽

Principle Density Functional Theory ◽

Specific Quantum

In this work, using the first-principle density functional theory (DFT) method, we study the properties of a new material based on pillared graphene and the icosahedral clusters of boron B12 as a supercapacitor electrode material. The new composite material demonstrates a high specific quantum capacitance, specific charge density, and a negative value of heat of formation, which indicates its efficiency. It is shown that the density of electronic states increases during the addition of clusters, which predictably leads to an increase in the electrode conductivity. We predict that the use of a composite based on pillared graphene and boron will increase the efficiency of existing supercapacitors.

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ChemInform Abstract: VERY LOW PRESSURE REACTOR. A NEW TECHNIQUE FOR MEASURING RATES AND EQUILIBRIUMS OF RADICAL-MOLECULE REACTIONS AT LOW TEMPERATURE. HEAT OF FORMATION OF THE METHYL RADICAL

Chemischer Informationsdienst ◽

10.1002/chin.197834111 ◽

1978 ◽

Vol 9 (34) ◽

Author(s):

M. H. BAGHAL-VAYJOOEE ◽

A. J. COLUSSI ◽

S. W. BENSON

Keyword(s):

Low Temperature ◽

Low Pressure ◽

Heat Of Formation ◽

New Technique ◽

Methyl Radical ◽

Temperature Heat ◽

A New Technique

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Identification of N-glycans with GalNAc-containing antennae from recombinant HIV trimers by ion mobility and negative ion fragmentation

Analytical and Bioanalytical Chemistry ◽

10.1007/s00216-021-03477-3 ◽

2021 ◽

Author(s):

David J. Harvey ◽

Anna-Janina Behrens ◽

Max Crispin ◽

Weston B. Struwe

Keyword(s):

Cross Sections ◽

Ion Mobility ◽

Travelling Wave ◽

Negative Ion ◽

Ion Fragmentation ◽

Structural Identity ◽

Immunodeficiency Virus ◽

Different Types ◽

Complex Glycans ◽

Ion Collision

AbstractNegative ion collision-induced dissociation (CID) of underivatized N-glycans has proved to be a simple, yet powerful method for their structural determination. Recently, we have identified a series of such structures with GalNAc rather than the more common galactose capping the antennae of hybrid and complex glycans. As part of a series of publications describing the negative ion fragmentation of different types of N-glycan, this paper describes their CID spectra and estimated nitrogen cross sections recorded by travelling wave ion mobility mass spectrometry (TWIMS). Most of the glycans were derived from the recombinant glycoproteins gp120 and gp41 from the human immunodeficiency virus (HIV), recombinantly derived from human embryonic kidney (HEK 293T) cells. Twenty-six GalNAc-capped hybrid and complex N-glycans were identified by a combination of TWIMS, negative ion CID, and exoglycosidase digestions. They were present as the neutral glycans and their sulfated and α2→3-linked sialylated analogues. Overall, negative ion fragmentation of glycans generates fingerprints that reveal their structural identity.

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