Cathodic Reduction of Zinc Oxide in Alkaline Electrolyte

Russian Journal of Electrochemistry - The reduction of zinc oxide in a limited volume of the alkaline electrolyte is studied. Methods of chronopotentiometry, chronoamperometry, and...     

Digital Simulation of Discharge of Nickel–Cadmium Batteries

Russian Journal of Electrochemistry - A computer analysis of the mathematical model for the nickel–cadmium battery discharge with different types of electrodes is presented. The model...     

Use of gold nanoparticles for immobilization of <Emphasis Type="Italic">L</Emphasis>-cysteine on TLC plates

A new method of immobilization of the chiral selector on the surface of TLC plates by means of stepwise impregnation by gold nanoparticles and L-cysteine is described. The novel silica- and alumina-based stationary phases for TLC demonstrate enantioselectivity toward tetrahydrozoline, hydroxyzine, ketoprofen, fenoprofen, pindolol, and fluoxetine. The influence of the composition of the mobile phase on the R _f values and enantioselectivity is also discussed.     

On extensions of the Bessel operator on a finite interval and a half-line

The minimum and maximum operators generated by a Bessel differential expression are studied. The boundary triplets for the maximum operator A _??,max are constructed, and the corresponding Weyl functions are found. All non-negative self-adjoint extensions of the minimum operator A _??,min are described.     

Separation and enantioseparation of derivatized amino acids and biogenic amines by high-performance liquid chromatography with reversed and chiral stationary phases

A lignosulfonate sample was fractionated according to the solubility in ethanol-water. The fractions were analysed by aqueous size exclusion chromatography (SEC) combined with in-line multi-angle laser light scattering (MALLS), and by static MALLS. Satisfactory SEC results were obtained with aqueous phosphate buffer containing DMSO and SDS. The refractive index increment (dn/dc) varied from 0.186 to 0.205 ml/g, depending on Mw and the degree of sulfonation. The second viral coefficient (A2) was 7 x 10(-3) ml mol/g2. The weight-average molecular weight (Mw) of the fractions varied from 4600 up to 398 000 g/mol. and the polydispersity (Mw/Mn) varied between 1.3 and 3.5.     

Separation of water-soluble vitamins on silica modified with L-cysteine–stabilized gold nanoparticles using HPLC

Silica functionalized with 3-aminopropyltriethoxysilane and L-cysteine–stabilized gold nanoparticles has been obtained (SiO₂–NH₂–Au–L-cysteine). The influence of pH and the content of acetonitrile in the mobile phase on retention and separation selectivity of eight vitamins has been studied. The chromatographic conditions that enable the separation of C, B3, B12, B5 and B1, B2, B6, B10 mixtures of vitamins have been proposed. It has been found that it is possible to separate a mixture of vitamins C, B3, B12, and B5 in 8 min, and a mixture of vitamins B1, B2, B6, B10 in 12 min on the synthesized sorbent SiO₂–NH₂–Au–L-cysteine in isocratic elution mode.     

Sorbent for the separation of enantiomers of amino acids based on silica gel modified with stabilized Au nanoparticles

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The dependence of lyotropic mesomorphism and intermolecular interactions of the carboxyphtalocyanine derivatives on the metal nature

Summary The existence of lyomesophases in the water systems of disklike molecules without the laterally surrounded longitudinal chains—carboxyderivatives of phtalocyanine and their metallocomplexes—is shown. The dependence in displaying of lyomesomorphism on the metal nature and the arrangement of carboxyl groups in molecule is defined. The structures of lyomesophases are determined. Work presented at the second USSR-Italy Bilateral Meeting on Liquid Crystals held in Moscow, September 15–21, 1988.