Synthesis and properties of isopropylamine borane i-C3H7NH2 · BH3

Isopropylamine borane i-C₃H₇NH₂ · BH₃ was synthesized by the reaction of sodium tetrahydroborate NaBH₄ with isopropylamine hydrochloride in tetrahydrofuran followed by extraction with diethyl ether. Its synthesis conditions were determined and optimized. The compound was characterized by chemical analysis, IR spectroscopy, and differential thermal analysis.     

On the Possibility of using Vertical Receiving Arrays for Underwater Acoustic Communication on the Arctic Shelf

Acoustical Physics - Numerical simulation is applied to analyze the possibilities of using vertical receiving arrays covering the entire waveguide for underwater acoustic communication on the...     

Investigation of charged-hadron production in proton–nucleus interactions at the energy of 50 GeV

Cross sections for the production of high-transverse-momentum charged hadrons in proton–nucleus interactions at the incident-proton energy of 50 GeV were measured with the aid of the FODS double-arm spectrometer. Single hadrons (charged pions and protons) emitted at a c.m. angle of about 90° and high-effective-mass pairs of hadrons flying apart at a c.m. angle of 180° were detected simultaneously. Results on the production of single hadrons are presented.     

Progress in development of Nuclotron accelerator complex

The Nuclotron superconducting synchrotron was constructed in 1987–1992 [1]; it is the world’s first synchrotron based on fast cycling “window frame” electromagnets with a superconducting coil. For a design field of dipole magnets of 2 T, the magnetic rigidity is 45 T m, which corresponds to the energy of heavy nuclei (for example, gold) of 4.5 GeV/nucleon. The Nuclotron accelerator complex is currently being upgraded (the Nuclotron-M project); this upgrade is considered a key part of the first stage of fulfilling the new Joint Institute for Nuclear Research (JINR) project: the Nuclotron-based Ion Collider fAcility and Multi-Purpose Detector (NICA/MPD). The most important task of this new project is the preparation of basic Nuclotron systems for its reliable operation as part of the NICA accelerator complex. Basic results of activity on the project, which started in 2007, are presented and the results of the last Nuclotron runs are analyzed.     

Generation of high-energy negative hydrogen ions upon the interaction of superintense femtosecond laser radiation with a solid target

The formation of a high-energy (～35 keV) beam of negative hydrogen ions was observed in the expanding femtosecond laser plasma produced at the surface of a solid target by radiation with an intensity of up to 2× 10¹⁶ W/cm². The energy spectra of the H⁺ and H^?-ions show a high degree of correlation.