Copper-polymer nanocomposite: An efficient catalyst for green Huisgen click synthesis

A new method for Huisgen [3+2] cycloaddition synthesis of 1,4- and 1,4,5-substituted-1H-1,2,3-triazoles was reported. The reaction was catalyzed by the product of thermolysis of copper (II) poly-5-vinyltetrazolate. Heterogeneous catalyst includes copper nanoparticles which supported on polymeric matrix. It presents recovered and recycled catalyst and the catalyzed reaction proceeds in aerobic conditions at room temperature in aqueous media.     

The first AMPA receptor negative modulators based on the tetrahydroquinazoline scaffold

A convenient approach to novel symmetric bispyrimidine diamines comprises S_NAr reactions of 4-fluoropyrimidine N-oxide with alkane-α,ω-diamines with subsequent reduction of N-oxide function. The obtained substances were tested in patch-clamp experiments for the influence on the kainateinduced currents in Purkinje neurons and showed negative modulating effect.

     

Precision measurement of nuclear muon capture by3He

In this article we report the results of an experiment performed in 1993 at PSI. The goal was to determine the absolute rate of nuclear muon capture by³He. In the experiment we used a new technique recently developed at Gatchina. As a preliminary result from this experiment we obtained _c=(1496±3(stat)-3(syst)) s^–1.     

Final dt stickingω s using the “survived moun method”

A new direct measurement of the final dt sticking probability _s using a special data analysis called the survived muon method is presented. The data were obtained at PSI using a high pressure ionization chamber with H/D/T gas mixtures. The method can provide information on final sticking dt +n independent of theoretical models of stripping and initial sticking. It was found: _s=(0.57±0.07±0.02)%. The experiment and the analysis method are discussed in detail.     

Experimental survey of the sticking problem in muon catalyzed dt fusion

The sticking process dt + n, which constitutes the most severe limit to the number of fusions which a muon can catalyze, is reviewed. Many attempts were made to determine by calculations and measurements the probability for initial sticking _s ⁰ (immediately after dt fusion) and for final sticking _s (after the came to rest). Previous results based on neutron disappearance rates and on the observation of -X-rays were controversial and also in some disagreement with theory. New data are reported from PSI on direct observation of final sticking, using a setup with the St. Petersburg ionization chamber. These data mark a significant improvement in reliability and may clarify questions concerning previous discrepancies. The new results is _s(0.56±0.04)%, lower than the theory prediction _s=(0.65±0.03)%, at medium density.     

Force fields for molecular dynamics simulation of the deposition of a silicon dioxide film

In this work we compare two force fields that are intended for the molecular dynamics simulation of the process of the deposition of silicon dioxide thin films. Analysis of the structural characteristics (the density and radial distribution function) of a glassy silicon dioxide cluster that was used as a substrate and a deposited film is carried out. It is shown that the DESIL force field in which the Van der Waals interaction is described by the Lennard–Jones potential turns out to be more suitable for modeling the process of deposition.     

Short peptide with an inhibitory activity on the NMDA/Gly-induced currents

ABSTRACT

N-methyl-D-aspartate (NMDA) receptors are considered to be one of the most promising targets for treatment-resistant depression. The majority of known ligands may cause undesirable side-effects, except tetrapeptide rapastinel which demonstrated rapid antidepressant effect without psychotomimetic side effects. High shape similarity was noticed between dipeptide Phe-Tyr and NMDA receptor non-competitive antagonist ifenprodil which imply the possibility for antagonistic action of this peptide. A series of analogs were selected based on the docking results and molecular dynamics simulations. A dipeptide D-Phe-L-Tyr showed modest inhibitory activity comparable to rapastinel.