Synthesis and Biological Activity of 3,4-Diaryl-5-[4-(acetylsulfamoyl)phenyl]-4,5-dihydropyrrolo[3,4-<Emphasis Type="Italic">c</Emphasis>]pyrazol-6(2<Emphasis Type="Italic">H</Emphasis>)-ones and Their Sodium Salts

3,4-Diaryl-5-[4-(acetylsulfamoyl)phenyl]-4,5-dihydropyrrolo[3,4-c]pyrazol-6(2H)-ones were synthesized be reaction of 5-aryl-4-aroyl-1-[4-(acetylsulfamoyl)phenyl]-3-hydroxy-1H-pyrrole-2(5H)-ones with hydrazine hydrate in glacial acetic acid, and their sodium salts were obtained by treatment with sodium methoxide in methanol–DMF (1: 1). Analgesic and anti-inflammatory activity and acute toxicity of the synthesized compounds were studied.     

Sorption of arsenic onto inorganic sorbents modified with iron compounds

Granulated inorganic sorbents based on silica gel of KSKG grade and aluminum oxide and modified with Fe(III) compounds were developed for water treatment to remove As(V). The influence of the particle size of the modifying additive on the ability of silica gel to take up As(V) was examined. The KSKG-based sorbents modified with nanoparticles of Fe(III) compounds exhibit the highest sorption capacity. The capacity of silica gel based sorbents modified with nanoparticles of iron compounds for As(V) is higher than that of analogous sorbents modified with iron oxides prepared by thermal decomposition of Fe(III) nitrate.     

A synergetic effect in nitrous acid formation by sonolysis of nitric acid in the presence of nitrous oxide

A synergetic effect is found in the sonochemical formation of HNO₂ in HNO₃ solution in the presence of an N₂O–Ar gaseous mixture. The maximum rate of HNO₂ formation is observed at an N₂O : Ar ratio of 15 : 85 (v/v). During the sonolysis of 4 M HNO₃ solutions, the rate of HNO₂ formation increases multifold due to the synergetic effect. The rate of sonochemical hydrazine decomposition in nitrate solutions also increases considerably in the presence of N₂O.     

RILIS applications at CERN/ISOLDE

Since 2011 the ISOLDE Resonance Ionization Laser Ion Source (RILIS) has comprised a dual system of three dye and three Ti:sapphire lasers capable of gap-free wavelength tuning from 210 to 950 nm. Temporal synchronization of the lasers has enabled several operating modes to be established which make optimal use of the complementary characteristics of each laser type. This flexibility of the system has presented several opportunities for additional atomic spectroscopy studies and ionization scheme development, whilst also enabling an increase in the number of operating hours for standard ion beam production. The extended capabilities of the dual-RILIS system are exemplified by the recent operational highlights. These include on-line ionization scheme development (At, Ca), measurements of ionization energies (At, Po), in-source resonance ionization spectroscopy of exotic isotopes (At, Au, Po), and the provision of a fibre-coupled narrow-linewidth Ti:sapphire beam for the on-line commissioning of the CRIS experiment (Fr).     

Formation of optical color and fluorescence centers in polytetrafluoroethylene under γ-irradiation

Fluorescent properties and colors of polytetrafluoroethylene (PTFE) samples were studied as functions of absorbed dose of γ-radiation at a temperature above the melting temperature of the crystallites (327°C) in the dose range 0.2–0.8 MGy. The samples were irradiated at low pressure (10^–6 Torr) in glass ampuls and at atmospheric pressure in a chamber purged with argon. Samples in ampuls acquired an off-white tint and fluoresced weakly. The fluorescence intensity increased slowly as the radiation dose increased from 0.2 to 0.6 MGy and decreased at 0.8 MGy. Samples irradiated in the chamber fluoresced more strongly and acquired colors that changed from gray (0.2 MGy) to dark-brown (0.8 MGy). Color centers were formed only in the sample surface layer. Their appearance was associated with the adsorption of particles of an unknown nature from the environment. The argon-purged samples turned white upon removing their surface layer (50 μm). The intensity and shape of fluorescence bands emitted by these samples remained essentially unaltered, i.e., depended weakly on the absorbed dose in the range 0.2–0.8 MGy.     

Yields and transverse momenta of the 6Li fragments in the emulsion at 4.5 GeV/c per nucleon

We present the results of the study of interaction of the relativistic ⁶Li nucleus with the momentum 4.5 GeV/c per nucleon with the photoemulsion. Yields of the ¹H (³He) and ²H (⁴He) isotopes due to the fragmentation of ⁶Li are found to be almost equal. Cross sections for the charge exchange and pickup reactions are found to be σ_exch=9±2 mb. The distributions of the fragment transverse momenta projected onto the emulsion plane are used to obtain the nucleon Fermi momentum of ⁶Li, P_F, this value being equal to 129±8 MeV/c. The high momentum component in the transverse momentum distributions of ³He and ⁴He isotopes is observed. Received: 4 August 1997     

Some parameters and conditions defining the efficiency of burners in the destruction of long-lived nuclear wastes

A number of new wordings and statements regarding the targeted problem of destruction of long-lived wastes (transmutation) is considered. Some new criteria concerning the efficiency of a particular burner type are proposed. It is shown that the destruction efficiency of a specific burner is greatly influenced by the prospective time period of the whole destruction process.      

A New Class of Homogeneous Visible‐Light Photocatalysts: Molecular Cerium Vanadium Oxide Clusters

The first systematic access to molecular cerium vanadium oxides is presented. A family of structurally related, di‐cerium‐functionalized vanadium oxide clusters and their use as visible‐light‐driven photooxidation catalysts is reported. Comparative analyses show that photocatalytic activity is controlled by the cluster architecture. Increased photoreactivity of the cerium vanadium oxides in the visible range compared with nonfunctionalized vanadates is observed. Based on the recent discovery of the first molecular cerium vanadate cluster, (nBu₄N)₂[(Ce(dmso)₃)₂V₁₂O₃₃Cl] ? 2 DMSO ( 1 ), two new di‐cerium‐containing vanadium oxide clusters [(Ce(dmso)₄)₂V₁₁O₃₀Cl] ? DMSO ( 2 ) and [(Ce(nmp)₄)₂V₁₂O₃₂Cl] ? NMP ? Me₂CO ( 3 ; NMP=N‐methyl‐2‐pyrrolidone) were obtained by using a novel fragmentation and reassembly route. Pentagonal building units {(V)M₅} (M=V, Ce) reminiscent of “Müller‐type” pentagons are observed in 2 and 3 . Compounds 1 – 3 feature high visible‐light photooxidative activity, and quantum efficiencies >10 % for indigo photooxidation are observed. Photocatalytic performance increases in the order 1 < 3 < 2 . Mechanistic studies show that the irradiation wavelength and the presence of oxygen strongly affect photoreactivity. Initial findings suggest that the photooxidation mechanism proceeds by intermediate formation of hydroxyl radicals. The findings open new avenues for the bottom‐up design of sunlight‐driven photocatalysts.     

Selective high temperature refractory target – laser ion source unit of IRIS facility

An artificial neural network for extracting reasonable and fast estimates of hyperfine parameters from Mössbauer spectra in the energy or time domain is outlined. First promising results for determining the asymmetry of the electric field gradient at the nucleus of a diamagnetic iron center as derived with different types of neural networks are reported.