Multicomponent reactions are a valuable tool for the synthesis of functional π-electron systems. Two different approaches can be taken into account for accessing the target structures. In the more conventional scaffold approach an already existing chromophore is coupled with other components to give a complex functional π-system. Here, electronically monotonous components can also be introduced...

Dedicated electron cloud diagnostics developed at the Advanced Photon Source (APS) enabled for the first time detailed characterization of the electron cloud (EC) properties in a highintensity positron and electron storage ring. From in situ measurements of the electron flux and energy distribution at the vacuum chamber wall, electron cloud production mechanisms and details of the beam-cloud in...

Photodriven electron-transport properties of the self-assemblies of N,N'-di(2-(trimethylammoniumiodide)ethylene)perylenediimide stacks (TAIPDI)(n) with three electron donors, disodium 4,4'-bis(2-sulfonatostyryl)biphenyl (BSSBP, stilbene-420), sodium 9,10-dimethoxyanthracene-2-sulfonate (DANS) and disodium 6-amino-1,3-naphthalenedisulfonate (ANADS) have been studied in water. These electron dono...

Effect of norfloxacin (Nor) on the sorption of 1,3-dinitrobenzene (1,3-DNB), and PAHs (naphthalene (NAPH), phenanthrene (PHEN) and pyrene (PYR)) to K(+)-montmorillonite was studied. Nor suppressed 1,3-DNB sorption due to their competition for the same sorption sites. 1,3-DNB was sorbed on K(+)-montmorillonite surface via cation-polar interaction and n-π electron donor-acceptor interaction. Nor ...

In many accelerators running positively charged beams, ionization of residual gas and secondary electron emission in the beam pipe will give rise to an electron cloud which can cause beam blow-up or the loss of the circulating beam. One solution to avoid the electron cloud is to ensure that the vacuum wall has low secondary emission yield (SEY). The SEY of thin films of TiN and sputter-deposite...

PEP-II B-factory operates at a record high circulating current currently ~2.5 A in the positron ring. Electron cloud effects became apparent [1] when the positron ring current reached ~ 0.7 A with a bunch current ~1.5 mA. Initially, electron cloud induced beam instabilities significantly limited collider luminosity [2]. However, suppression of the electron cloud related beam instabilities have ...

The cross section of the process e+ e– → π+ π– π0 was measured with CMD-3 detector at electron-positron collider VEPP-2000 in ω meson energy region based on data collected 2013–2018 and corresponding to an integrated luminosity 40 pb–1. parameters ω-meson: Mω = 782.67 ± 0.01 0.1 MeV, Γω 8.56 0.02 0.07 σ0(ω π) 1629 3 36 nb precision match or even exceeding previous are obtained.

Electron cloud due to beam-induced multipacting can generate transverse instabilities and beam size blow-up in both positron and proton accelerators. A solenoid satisfactorily suppresses multipacting in the drift region by confining the electrons close to the walls’ surface. There is a long drift region in the KEKB LER, wherein a solenoid occupies most of the beam’s pipe. We investigated the so...

Hydrogen bonding is of fundamental importance for structure, function, and dynamics in a vast number of chemical and biological systems. 6 In conventional hydrogen bonds, X H 3 3 3A, a hydrogen atom bridges the proton donor X and proton acceptor A. The donor is usually very electronegative, for example, O or N, whereas the acceptor is an electronegative atom with at least one lone pair of elect...

Simulation studies of electron cloud multipacting were performed for the SLAC B-factory vacuum chamber for different bunch trains and solenoidal magnetic field. Results show that increasing the number of positron bunches by a factor of two and keeping the same current per bunch means that the solenoidal field needs to be doubled in order to keep the same electron cloud density. Fortunately ther...