ThDione: A Powerful Electron‐Withdrawing Moiety for Push–Pull Molecules

ChemPlusChem ◽  
2020 ◽  
Vol 85 (7) ◽  
pp. 1549-1558
Author(s):  
Eva Novotná ◽  
Iwan V. Kityk ◽  
Oldřich Pytela ◽  
Filip Bureš ◽  
Miroslav Ludwig ◽  
...  
Keyword(s):  
Powerful Electron

Powerful electron accelerator for the production of neutrons and radioisotopes

2019 ◽  
Vol 2019 (4) ◽  
pp. 142-152
Author(s):  
Elena Aleksandrovna Onischuk ◽  
Yurij Aleksandrovich Kurachenko ◽  
Evgenij Sergeevich Matusevich
Keyword(s):  
Electron Accelerator ◽  
Powerful Electron

Radiative properties of impure molecular crystals on excitation by a powerful electron beam

1990 ◽  
Vol 53 (3) ◽  
pp. 984-987
Author(s):  
V. V. Gruzinskii ◽  
V. S. Gorobchenko ◽  
S. V. Davydov ◽  
V. V. Eremenko ◽  
I. I. Kulak ◽  
...  
Keyword(s):  
Electron Beam ◽  
Molecular Crystals ◽  
Radiative Properties ◽  
Powerful Electron

On powerful electron beam relaxation in magnetized plasmas

1987 ◽  
Vol 121 (4) ◽  
pp. 178-181
Author(s):  
M.A. Berezovskii ◽  
A.I. Dyachenko ◽  
I.V. Petrov ◽  
A.N. Pushkarev ◽  
A.M. Rubenchik
Keyword(s):  
Electron Beam ◽  
Magnetized Plasmas ◽  
Powerful Electron

Commissioning of a powerful electron gun for electron–ion crossed-beams experiments

2017 ◽  
Vol 408 ◽  
pp. 317-322 ◽  
Author(s):  
Benjamin Ebinger ◽  
Alexander Borovik ◽  
Tobias Molkentin ◽  
Alfred Müller ◽  
Stefan Schippers
Keyword(s):  
Electron Gun ◽  
Crossed Beams ◽  
Powerful Electron

Two-Dimensional Numerical Model for Studies of Collective Beam-Plasma Interaction

2010 ◽  
Vol 5 (2) ◽  
pp. 85-97
Author(s):  
Andrey V. Terekhov ◽  
Igor V. Timofeev ◽  
Konstantin V. Lotov
Keyword(s):  
Numerical Model ◽  
Electron Beams ◽  
Modulational Instability ◽  
Two Dimensional ◽  
Particle In Cell ◽  
Plasma Energy ◽  
Proposed Model ◽  
The Laplace Operator ◽  
Physical Phenomena ◽  
Powerful Electron

A two-dimensional particle-in-cell numerical model is developed to simulate collective relaxation of powerful electron beams in plasmas. To increase the efficiency of parallel particle-in-cell simulations on supercomputers, the Dichotomy Algorithm is used for inversion of the Laplace operator. The proposed model is tested with several well-known physical phenomena and is shown to adequately simulate basic effects of the beam driven turbulence. Also, the modulational instability is studied in the regime when the energy of pumping wave significantly exceeds the thermal plasma energy

Fasteners: Acid Catalysis

Reactions ◽  
2011 ◽  
Author(s):  
Peter Atkins
Keyword(s):  
Acetic Acid ◽  
Acid Catalysis ◽  
Positive Charge ◽  
Proton Donor ◽  
Electron Cloud ◽  
Base Catalysis ◽  
Acid Molecule ◽  
General Basis ◽  
Missile Attack ◽  
Powerful Electron

I explained the general basis of catalysis in Reaction 11, where I showed that it accelerated a reaction by opening a new, faster route from reactants to products. One of the ways to achieve catalysis in organic chemistry is to carry out a reaction in an acidic or basic (alkaline) environment, and that is what I explore here. In Reaction 27 you will see the enormous importance of processes like this, not just for keeping organic chemists productive but also for keeping us all alive; I give a first glimpse of that later in this section too. Various kinds of acid and base catalysis, sometimes both simultaneously, are going on throughout the cells of our body and ensuring that all the processes of life are maintained; in fact they are the very processes of life. I deal with acid catalysis in this section and base catalysis in the next. The point to remember throughout this section is that an acid is a proton donor (Reaction 2) and a proton is an aggressive, nutty little centre of positive charge. If a proton gets itself attached to a molecule, it can draw electrons towards itself and so expose the nuclei that they formerly surrounded. That is, a proton can cause the appearance of positive charge elsewhere in the molecule where the nuclei shine through the depleted fog of electrons. Because positive charge is attracted to negative charge, one outcome is that a molecule may be converted into a powerful electron-sniffing electrophile (Reaction 16). Another way of looking at the outcome of adding a proton is to note that a C atom with a positive charge is a target for nucleophilic missile attack (Reaction 15). Therefore, if a proton draws the electron cloud away from a nearby atom, then its presence is like a fifth-column agent preparing a target for later attack. Let’s shrink and watch as some acid is added to a molecule that contains a –CO– group, such as acetic acid. The protons provided by the added acid are riding on water molecules, as H3O+ ions, and arrive in the vicinity of the acetic acid molecule.

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