Resonance states of hydrogen nuclei 4H and 5H obtained in transfer reactions with exotic beams

To investigate ⁵H resonance states with a better instrumental resolution, we utilized the two-neutron transfer reaction ³H(t, p)⁵H accomplished with the use of a cryogenic liquid-tritium target and 57.5-MeV triton beam. As a result of this study, a valuable fraction of protons detected at ? _lab=18°–32° in ptn coincidence events was attributed to the states of the ⁵H nucleus. Two resonance states situated at 1.8±0.1 and 2.7±0.1 MeV above the t + n + n decay threshold were obtained in the missing mass energy spectrum of the ⁵H nucleus. The peak located close to E5_H was clearly seen in the ⁵H spectrum obtained from the energy distributions of ³H nuclei emitted in the reaction ²H(⁶He, ⁵H)³He at ? _lab=17°–32°. The width (Γ_obs≤0.5 MeV) obtained for the two ⁵H resonance states is surprisingly small. A state of ⁴H with E _res=3.3 MeV and γ ²=2.3 MeV was obtained in the reaction ²H(t, p)⁴H from the spectra of protons leaving the target at ? _lab=18°–32° and detected in coincidence with neutrons emitted in the decay of ⁴H nuclei.     

Study of formation of metal–polymer complexes between copper (I) and polyamic acids by HPLC

Structural, molecular, and hydrodynamic characteristics of thermostable functionalized polymers [polyamic acids (PAAs) with biquinoline chelate groups in the main chain] were studied by high-performance liquid chromatography. Size exclusion mechanism of chromatography in conditions including suppression of polyelectrolyte swelling and ion-exclusion effects was proved. The influence of molecular and structural characteristics of PAAs on their ability to form metal–polymer complexes (MPCs) with copper(I) chloride was studied. The critical polymer concentration at which binding of two PAA macromolecules with Cu⁺ ion takes place to form MPCs was estimated.     

Synthesis of complexes of N-vinylpyrrolidone–vinylamine or N-vinylpyrrolidone–allylamine containing macrocyclic polyligand 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetate (DOTA) with gallium-68 isotope and estimation of their in vivo distribution

Russian Chemical Bulletin - A method for radiolabeling the water-soluble N-vinylpyrrolidone copolymers with N-vinyl- and N-allylamine containing bifunctional chelation unit...     

Consideration of the volume changes in describing concentration front migration in electrolyte solutions

It is possible to avoid certain difficulties in describing the diffusion in electrolyte solutions by taking into account the process of spatial rearrangement of species that accompanied the concentration variations and was recently introduced into consideration. The experimental substantiation of taking into account this process is the different concentrations of solvent, i.e., water, observed in solutions of different concentrations.     

An atmospheric pressure ionization source based on desorption electrospray ionization technology (DESI) for ion cyclotron resonance mass spectrometry

An atmospheric pressure ionization source based on desorption electrospray ionization technology for a bench-top hybrid FTICR mass spectrometer is described. The ion source was characterized using low-molecular-weight-weight pharmaceutical samples. The dependences of signal intensities on various experimental parameters (solvent composition, surface temperature, spray voltage, etc.) were studied. Based on the results obtained, plausible mechanisms of desorption electrospray ionization for the analytes under the study are discussed.     

Some exact representations for the three-dimensional thermoelastic problem

Some exact representations are obtained for the three-dimensional thermoelastic problem in a rectangular parallelepiped. We give an exact solution of the Dirichlet problem taking account of edges and angles. We use the Papkovich-Neiber representation.Translated fromMatematicheskie Melody i Fiziko-Mekhanicheskie Polya, Issue 35, 1992, pp. 89–93.