Modernization of the Carpet-2 array of the Baksan Neutrino Observatory

The state of the art and the project of modernization of the extensive-air-shower array Carpet-2 of the Baksan Neutrino Observatory of the Institute for Nuclear Research, Russian Academy of Sciences are described. The modernized array will allow the performance of detailed study of variations in the cosmic ray intensity, the energy spectra and composition of primary cosmic rays in the energy range 10¹³–10¹⁶ eV, and the anisotropy of primary cosmic rays with energies above 10¹³ eV.     

An explicit formula for |FM(1+1+n)|

We show that the number of elements in FM(1+1+n), the modular lattice freely generated by two single elements and an n-element chain, is 1 $$\frac{1}{{6\sqrt 2 }}\sum\limits_{k = 0}^{n + 1} {\left[ {2\left( {\begin{array}{*{20}c} {2k} \\ k \\ \end{array} } \right) - \left( {\begin{array}{*{20}c} {2k} \\ {k - 2} \\ \end{array} } \right)} \right]} \left( {\lambda _1^{n - k + 2} - \lambda _2^{n - k + 2} } \right) - 2$$ , where \(\lambda _{1,2} = {{\left( {4 \pm 3\sqrt 2 } \right)} \mathord{\left/ {\vphantom {{\left( {4 \pm 3\sqrt 2 } \right)} 2}} \right. \kern-0em} 2}\) .     

New tetrazole-1-acetic acid esters for enzymatic synthesis of cefazolin

The enzymatic synthesis of cefazolin (CEZ) using esters of tetrazole-1-acetic acid (TzAA esters) with saturated lower alcohols is reported. The optimum ratios of acyl-donor:acyl-acceptor in the enzymatic synthesis were determined. It is shown that a threefold molar excess of acyl-donor for about 165 min, a conversion rate of about 55% is obtained with these TzAA esters. The syntheses were carried out with commercial immobilized penicillinamidase/E.C.3.5.1.11/ (Eupergit PcA) in a batch-type reactor. After 40 batches, the enzyme activity loss was 5–7% toward the initial one.     

IR-LD Spectral Study and ab Initio Calculations of 1-Phenyl 3-Substituted Pyrazol-5-Ones

The stereo structural characterization of 1-phenyl-3-methyl (MPhP)- and 1-phenyl-3–phenyl (DPhP)-pyrazol-5-ones are achieved by means of a linear dichroic infrared spectral (IR-LD) spectroscopy of samples dissolved in nematic liquid crystal. The results, thus obtaining in both cases indicate a coplanar disposition of 1-phenyl substituent towards the pyrazole fragment, however, the benzene ring attached at 3-position in DFP is significantly deviated form the pyrazolone skeleton plane. Additionally the geometry parameters of both compounds are estimated by ab initio calculations using 6-31G** basis set on Hartee-Fock level of theory. The predicted stereo structure confirms the results achieved by the IR-LD spectral study that is in a good agreement with the X-ray data of the discussed pyrazol-5-ones derivatives.     

Influence of ultraviolet light on some copper chelates of β-dicarbonyl compounds : Spectral evidence for a photoactivated metallotropy

The influence of ultraviolet light on heptane solutions of the copper chelates of several β-dicarbonyl compounds has been followed by spectroscopy. Reversible transformations are apparent, leading us to assume the presence of a photoactivated metalotropy.     

Effect of polymerization rate on the polyethylene structure obtained with a high activity catalyst system

The effect of polymerization rate on polyethylene structure, using magnesium reduced titanium tetrachloride catalysts together with the usual aluminium alkyl activator, is described. It is shown that the polymer bulk density and the nascent super-molecular structure formed during ethylene polymerization depends upon the rate of polymerization. The results indicate that, with increasing polymerization rate, the catalyst active sites produce polymer with different densities. One possible explanation for this phenomenon lies in considering the inhibition of crystallization by high polymerization rates. Experimental results on different polymer morphologies are discussed. Finally models for the structure of polymer particles are considered briefly.     

Large-volume detector at the Baksan Neutrino Observatory for studies of natural neutrino fluxes for purposes of geo- and astrophysics

At the Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy of Sciences, Moscow) deployed in the Caucasus mountains, it is proposed to create, at a depth corresponding to 4760 mwe, a large-volume neutrino detector on the basis of a liquid scintillator with a target mass of 10 kt. The detector in question is intended for recording natural fluxes of neutrinos whose energy may be as low as 100MeV. Neutrino fluxes from various sources are considered in the present study, and the expected effect in the proposed detector is estimated. The detector hat is being developed at the Baksan Neutrino Observatorywill become part of the world network of neutrino detectors for studying natural neutrino fluxes.     

The Structure Formation of Zirconium Oxide Gels in Alcoholic Solution

Zirconium oxide gels were prepared by controlled hydrolysis and condensation of zirconium-n-propoxide in alcoholic solution. After completion of the gelation the aging and drying of the alcogel was observed in situ by Small and Wide Angle X-ray Scattering experiments at room temperature. The xerogels obtained have been annealed at different temperatures to crystallization. The structural changes were observed by using SAXS and WAXS. Structural models reproducing the experimental WAXS data have been simulated by the reverse Monte Carlo method. A comparison between zirconium oxide xerogels obtained under different thermal treatments was made and evidence was found that thermal treatment at higher temperatures and preparation conditions affect the atomic arrangement of these amorphous gels.