New Protective Coatings for Replacing Cadmium Coatings on Steel Parts

Works aimed at solving the problem of replacing toxic cadmium coatings used for protection of aircraft steel parts are reviewed. Numerous electrolytic alloys based on zinc and zinc-bearing coatings of the Colsil and Dacromet types are suggested for the purpose. A VIAM-designed coating based on a Zn – Sn alloy in combination with a modified phosphate coating is considered. It is shown that the protective properties of the combined coating are close to those of a cadmium coating, and the former is recommended for commercial use.     

High-temperature catalysts with a synergetic effect of Pd and manganese oxides

A synergetic effect in the catalytic activity has been found after palladium introduction in Mn–Al–O systems. The magnitude of the synergetic effect depends on the types of the oxidic manganese species: oxide Mn₃O₄, spinel (Mn, Mg)[Mn, Al]₂O₄ or hexaaluminate (Mn, Mg)LaAl₁₁O₁₉. The synergetic effect of Pd and manganese-containing compounds is observed only if palladium is introduced to the low-temperature precursor of the manganese alumina spinel or manganese hexaaluminate. The synergetic effect is not observed when high-temperature samples with formed spinel or hexaaluminate phases are modified with Pd.     

New tetra- and octa-functionalized phthalocyanines: Methods of synthesis and physicochemical properties in aqueous solutions and on solid substrates. Review

Methods of synthesis of a number of new functionalized phthalocyanines, as well as Mg^II, Co^II, Cu^II, Zn^II, and Ni^II phthalocyaninates, that involve benzo-15-crown-5-, phosphoryl-, or pyridine-containing fragments as peripheral substituents, which were developed and tested in IPCE RAS in the last five years, are reviewed and systematized. Methods of synthesis of the original phthalogens, which involve substituents of diverse composition, are considered. Results of an investigation of the aggregate states of the compounds in water and aqueous solutions of salts are generalized. The possibilities of electrostatic immobilization of the synthesized phthalocyanines in the form of self-assembled systems composed of ultrathin ionic layers on quartz and conductive glasses are considered. Based on the spectral, electrochemical, and electrocatalytic properties, the role of noncovalent interactions in the synthesis and operation of the composite systems is clarified.     

Statistical studies of the neutron flux density in a nuclear reactor with random perturbations of the properties of the surroundings

A mathematical model and research results on the characteristics of the neutron flux density in a reactor with feedbacks and random perturbations of the multiplication properties are described. The results of modeling and statistical analysis of in-reactor monitoring data are presented for RBMK. The results of numerical modeling of the determination of the onset threshold for xenon oscillations in a reactor with nonuniform loading over the core height are presented.     

Prospects for the use of the combined physicochemical and microbiological enhanced oil recovery technique in the White Tiger oil field (Vietnam)

Reservoir fluids of the White Tiger oil field (Vietnam) were studied for the purpose of the development of the combined physicochemical and microbiological technique of enhanced oil recovery. The reservoir conditions of the oil field facilitate the formation of numerous and versatile biocenosis represented by microorganisms of the Pseudomonas, Bacillus, Arthrobacter, Micrococcus, Nocardia, Brevibacterium, Flavobacterium, etc. genera. These microflora positively respond to the introduction of an oil-displacement composition at a concentration of up to 5% as a nitrogen nutrient source. The active multiplication of the microflora is accompanied by the oxidation of saturated White Tiger petroleum hydrocarbons: the proportion of C₁₀–C₁₅ and C₂₁–C₂₆ decreases, the proportion of the isoprenoid hydrocarbons pristane and phytane increases, and the isoprenoid factor increases from 0.54 in the initial oil to 1.65 after its biodegradation. A simulation of the displacement of viscous oil with the use of the detergent composition and hydrocarbon-oxidizing microflora has shown a 12–14% increment in the oil-displacement efficiency, where the contribution of microflora is estimated at 4–6%.