Kinetics of alkaline hydrolysis of ethylp-nitrophenyl ethylphosphonate in the reverse micellar system: sodium dodecyl sulfate-hexanol-water

The kinetics of alkaline hydrolysis of ethylp-nitrophenyl ethylphosphonate in the reverse micellar system sodium dodecyl sulfate—hexanol—water was studied. At high pH and low water content, the process occurs at the surface layer and can satisfactorily be described by the pseudo-phase model equation. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp 262–266, February, 2000.     

Color center formation by synchrotron radiation in the Na6Al6Si6O24(Nal)1.6 optical ceramic

The spectrum of F-center excitation by 5-to 27-eV photons in the Na₆Al₆Si₆O₂₄(NaI)_2x sodalite optical ceramic (x=0.8) was measured at 80 K by high-sensitivity photoexcited luminescence techniques. The F-centers are created by photons with an energy of 5.6-to 8.5 eV through the excitation and ionization of iodine centers of two types; in the 8.2-to 27-eV region, through the generation of electronic excitations in the aluminosilicate framework of alternating Al³⁺ and Si⁴⁺ ions, each coordinated tetrahedrally by oxygen ions. At the low irradiation doses used, the F centers are created primarily through photoelectron capture by the iodine vacancies which exist before irradiation. In the 23-to 25-eV region, the efficiency of F-center formation doubles as a result of the multiplication of electron-hole pairs.     

Aggregation behavior and catalytic properties of systems based on aminomethylated calix[4]resorcinarenes and poly(ethylene) imines

Self-assembling in systems poly(ethylene) imine-aminomethylated calix[4]resorcinarene-water-DMF (30 vol%) and catalytic properties of these compositions in hydrolysis of 4-nitrophenylbis (chloromethyl)phosphinate are studied. Critical concentrations of association, aggregates radii, and kinetic parameters of the reaction are established.     

Sulfonation of 10-carboxymethylene-9-acridanone under thermal and microwave conditions. Comparison of kinetic parameters

Sulfonation of 10-carboxymethylene-9-acridanone under thermal and microwave conditions was studied. The rate constants of the accumulation of the desired product in the reaction conditions were measured.     

Studies of porphyrin zinc compounds intercalated into V<Subscript>2</Subscript>O<Subscript>5</Subscript> xerogel

The intercalation of meso-tetrakis(4-pyridyl)porphyrin zinc, the cationic salts of meso-tetrakis(N-methylpyridinium-4-yl)porphyrin zinc, and zwitterionic meso-tetrakis-[N-(3-sulfonatopropyl)pyridinium-4-yl]porphyrin zinc from aqueous solutions as well as of meso-tetrakis(N-methylpyriclinium-4-yl)porphyrin zinc from pyridine solutions into V₂O₅ xerogel was studied. The intercalation complexes obtained were characterized by X-ray diffraction analysis, TG analysis, IR, and UV reflectance spectroscopy.     

Generation of narrowly directed X-rays under optical pumping in synthetic opal matrices

Generation of narrowly directed X-rays in synthetic opal matrices upon pulsed laser excitation was detected. It was experimentally shown that this phenomenon occurs simultaneously with stimulated globular light scattering (SGLS) and the photon flame effect (PFE). Possible mechanisms of this effect were considered.     

Calculation of effective parameters of thermoelectromagnetoelastic layered media

A system of layered multiferroic materials is averaged with allowance for thermal properties of layers. Matrix averaging is used to obtain effective parameters of the system. Formulas that make it possible to characterize the effect of magnetoelectroelastic coefficients of layers on thermal parameters are derived. The presence of pyrocoefficients in the system is possible even in the absence of the coefficients for the layers. The heat capacity of the system ceases to be an additive quantity and becomes dependent on permittivity and permeability of the layers owing to the interaction of the fields.     

Hydrolysis of bis(4-nitrophenyl) ethyl phosphate in micellar solutions of dicationic surfactants

The effect of dicationic surfactants on the hydrolysis of bis(4-nitrophenyl) ethyl phosphate in a borate buffer is studied. The presence of long-chain surfactants results in a significant (up to 50-fold) increase in the observed rate constant (k _obs) of the process. The catalytic effect of micelles increases with increasing alkyl chain length due to the strengthening of binding of the reagents by micelles. The presence of two cationic centers in the surfactant molecule enhances the catalytic properties of micelles. The dependence ofk _obs of hydrolysis of the substrate on the borate buffer concentration is studied. Alkaline hydrolysis is more sensitive to the added surfactant than the reaction involving borate ions.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1576–1580, September, 1994.     

Inhibition of Alkaline Hydrolysis of Ethyl p-Nitrophenyl (Chloromethyl)phosphonate in the System Cationic Surfactant-Water-Electrolyte

The rate of alkaline hydrolysis of ethyl p-nitrophenyl (chloromethyl)phosphonate in micellar solutions of cationic surfactants decreases with increasing concentration of chloride, bromide, and salicylate ions. In the presence of electrolytes, the critical micell concentration of surfactants and the surface potential of micelles also decrease.