Synthesis of (o-Carborane-1,2-diyl)dipropanoic Acid and Its Derivatives

Hydrolysis of 1,2-bis(cyanoethyl)-o-carborane easily available by cyanoethylation of o-carborane gives (o-carborane-1,2-diyl)dipropanoic acid. The corresponding acid dichloride, diamide, dianilide, dibenzophenone, and diol were prepared from it by typical procedures.     

meso-spacer influence on properties of zinc(II) complexes with 2,3′- and 3,3′-bis(dipyrrolylmethenes)

The study and comparative analysis of spectral-luminescent characteristics (absorption and fluorescence spectra), of quantum yield, and fluorescence life time in solutions, of lability in proton-donor media, solid phase thermal stability in air oxygen and argon was carried out for binuclear zinc(II) helicates with decamethyl-substituted 2,3′- and 3,3′-bis(dipyrrolylmethenes). The influence of molecular structure features of the ligands on the physicochemical properties of helicates was discussed.     

Plasma Synthesis and XPS Attestation of Thin-Film Carbon Coatings with Predetermined sp-Hybridization

Physics of Atomic Nuclei - The diversity of carbon materials has allowed them to be used for fundamental and applied research to date. The newest modifications of carbon, such as nanodiamonds,...     

The comparison of binary- and ternary-fission configurations close to the instant of scission

A new way to bring into comparison the binary- and ternary-fission configurations is proposed. The method is founded on recently discovered ROT effect. The angle of fission axis deflection from its initial orientation at the moment of scission comes into existence as a result of dividing system rotation and carries information about fissioning nucleus deformation. The comparison of proper angles for binary and ternary fission can be used to estimate the difference in the rupture configurations.     

Kinetics of homogeneous dehydrogenation of formic acid in the presence of supramolecular rhodium(III) complex with P-functionalized calix[4]resorcine

The kinetics of homogeneous dehydrogenation of formic acid in the presence of supramolecular rhodium(III) complex with P-functionalized calix[4]resorcine were studied in dioxane, tetrahydrofuran, dimethylformamide, and binary formamide-dioxane mixtures (volume ratio 10: 90, 20: 80, 30: 70) over a wide temperature range (40?C90°C). The examined Rh(III) complex catalyzed the dehydrogenation process, and its catalytic activity was higher than that observed previously for rhodium complexes with non-macrocyclic phosphorus-containing ligands. The dehydrogenation rate constants were proportional to neither catalyst concentration nor dielectric constant of the medium, which is likely to be related to supramolecular nature of the Rh(III) complex. No micelle formation was observed in the examined systems.     

Peculiarities of temperature behavior of low-molecular fluorooligomers

The peculiarities of the behavior, structure, and properties of low-molecular fluoropolymers (fluorooligomers), namely, industrial fluoroparaffins and derivatives resulting from the thermal processing of ultradisperse powders of FORUM^® trademark, are studied. The results are obtained on the basis of the IR spectroscopic investigation of the products of pyrolysis of the fluorooligomers. The measurement data on rheological properties of the samples upon heating are analyzed.     

The influence of ms-substitution on the properties of 3,3′-bis(dipyrrolylmethenes) and their coordination compounds

We have compared the coordination properties of decamethyl-substituted 3,3′-bis-(dipyrrolylmethenes) (H₂L) with different ms-spacers separating the dipyrrolylmethene domains: methylene -CH₂-, methoxyphenylmethylene -CH(p-C₆H₄OMe)-, and trifluoromethylmethylene -CH(CF₃)-. The stable binuclear homoligand complexes [M₂L₂] are formed in reactions of the ligands with Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II) acetates. In the cases of all H₂L ligands the thermodynamic constants of the complex formation reactions increase in the following series: Cu(II) < Cd(II) < Hg(II) < Ni(II) < Co(II) < Zn(II). The change in -CH₂- ms-spacer to -CH(p-C₆H₄OMe)- or -CH(CF₃)- results in a decrease in the constant of H₂L complex formation by 1–4 orders of magnitude, the cation being the same. The influence of ms-substitution on the stability and luminescence properties of [M₂L₂] has been discussed.     

Preparation and spectral properties of Zn(II) complexes with aryl-substituted dipyrrolylmethene and azadipyrrolylmethene

The homoleptic complexes of Zn(II) with 3,3′,5,5‘-tetraphenyl-2,2’-dipyrrolylmethene and 3,3′,5,5′-tetraphenyl-ms-aza-2,2′-dipyrrolylmethene [ZnL₂] have been prepared, and their spectral and luminescent properties have been studied. The complex with 3,3′,5,5′-tetraphenyl-2,2′-dipyrrolylmethene exhibited an intense fluorescence in the nonpolar medium, efficiently quenched in the polar solvents; thus, it can be used as a fluorescent sensor of the medium polarity.     

A review of furfural derivatives as promising octane boosters

Prospects for using furfural derivatives as octane boosters for gasoline are discussed on the basis of analysis of their physicochemical and operation properties. Knock resistance data, toxicity parameters, and results of motor bench tests are considered for furan compounds, furfural ethers, furfurylamine, and other furfural derivatives.     

Efficiency of the production of γ families with halos and the fraction of protons at an energy of 10<Superscript>16</Superscript> eV

γ Families with halos detected in the “Pamir” experiment have been analyzed. Comparison of the experimental data with the results of calculation within the quark-gluon string model (MC0 code) made it possible to determine the efficiency of halo formation by protons, α particles, and heavy nuclei, as well as the fraction of protons in the mass composition of primary cosmic rays at an energy of 10¹⁶ eV. It is shown that halos are formed predominantly by protons. The fraction of protons in the mass composition of primary cosmic rays at an energy of 10¹⁶ eV is 20%.