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The possibility of using a composite material (hereinafter referred to as composite) based on silica gel modified with particles of Fe(III) compounds for the highly efficient purification of contaminated transformer oils and batches of oils for long-term storage is investigated. The KSKG silica-derived composite modified with particles of Fe(III) compounds with an iron content of about 7 wt % (SiO2-7Fe-Amk-600) is found to be more effective when compared with pure KSKG silica gel for removing both acid activators for sludge formation and oil-degradation products from transformer oils. The preservation of the basic properties of oil after its purification on the SiO2-7Fe-Amk-600 composite and storage for 2 years in contact with this composite indicates the possibility of using the new SiO2-7Fe-Amk-600 composite as a stabilizer for the original and purified transformer oils.

Changes in the molecular-weight distributions of low-molecular-weight and alkali cellulose after the processes of γ-irradiation and mercerization of cellulose have been studied. The features of the dissolution of irradiated cellulose in an alkaline solution during mercerization have been revealed. It has found that the alkali cellulose produced from the irradiated polymer has increased homogeneity of the molecular-weight distribution. The γ-irradiation of cellulose before mercerization leads to an increase in the reactivity of the polymer in the xanthogenation reaction by 30–50%. An optimum range of absorbed doses for the radiation pretreatment of cellulose prior to a viscose production process has been determined.

The effect of γ-irradiation of cotton cellulose on the molecular-weight distribution (MWD) of the nitro esters prepared from the irradiated cellulose has been studied. It has been established that the degradation of cellulose during the sulfuric acid–free nitration in fuming nitric acid occurs according to a random law with the most probable MWD, whereas the esters obtained in a sulfuric acid–nitric acid nitration mixture are almost uniform in terms of MWD. The rate constants of degradation by nitration increase with the absorbed dose. An increase in the uniformity of the nitro esters as a result of the washing out of the low-molecular-weight fraction improves their physicomechanical characteristics. An equation is proposed for describing the kinetics of degradation of irradiated cotton cellulose during its nitration in fuming nitric acid.

The MASHA facility [1–3] was developed as a high precision mass-spectrometer for heavy and super heavy elements with masses up to 450 a.m.u. It uses ISOL (Isotope Separation On-Line) method. Its unique properties opens great prospective for the investigation of neutron-rich nuclei produced in multinucleon transfer reactions. Mainly nuclei near the neutron N = 126 and N = 152 shell closures are of great interest. This region of nuclei is not so far thoroughly enough investigated while its research has direct relation to the synthesis of super heavy elements. As is known the island of stability close to super heavy elements (Z = 112–118) exists due to the shell effects in nuclei. More detailed investigation of these shell effects can greatly help in the synthesis of next super heavy elements. Heavy neutron rich radon isotopes were produced in the multinucleon transfer reaction 40Ar + 232Th at Flerov Laboratory of Nuclear Reactions, Dubna. Radon isotopes with given masses were detected using two types of detectors: a multi-strip well-type detector (made in Canberra) and a position-sensitive quantum counting hybrid pixel detector of the Timepix type [1]. The latter detector has an array of 256×256 square pixels each with a pitch size of 55 μm for the full sensitive area 14×14 mm2. Radon isotopes implanted into the detector emit then alpha and beta particles until they reach the stable or long-lived isotopes at the end of their decay chains. The positions of radon isotopes, the tracks, times and energies of the beta particles were measured and analyzed. New software for the particle recognition and data analysis of the results obtained from the experiment was developed and used. It has been proven that MASHA + Timepix setup is a powerful instrument for investigation of neutron-rich isotopes far from stability limits.

It is demonstrated that during secondary refining at the ladle furnace the carbon content of steel and the residence time of the metal in the ladle exert a significant impact on the residual content of non-metallic inclusions (NMI) in steel. Mathematical calculations showed that the dynamic forces have minor effect on the motion of small sized NMI, making it difficult to penetrate deep into the slag.

Detection of bovine leukemia virus in dried blood spots by the polymerase chain reaction (PCR) was performed using a new format of membrane system for sample collection. The analysis results of liquid and dried samples of bovine whole blood were entirely consistent with each other and with the data of a veterinary laboratory. It was found that any part of a membrane strip with size of 0.5 × 0.5 cm containing an applied sample can be used for detection of a viral DNA copy. Provirus DNA in dried blood spots was stable for 8 days at 37°C and for 24 hours at 60°C. The new system for the sampling of whole blood in the form of dried spots can be used for sampling in field conditions for subsequent laboratory analysis.

A commercial homogenized ingot from alloy 1421 of the Al – Li – Mg – Sc – Zr system is studied. The elemental composition of the phases is determined. Thermograms are obtained for melting and crystallization of the alloy. The temperature ranges and the succession of formation of phases in nonequilibrium crystallization of alloy 1421 are determined.

The radiational-thermal development of coil short circuits due to the action of partial discharges of the first kind when the windings of transformers, autotransformers and shunting reactors become contaminated with metal-containing colloidal particles, formed in the transformer oil as a result of the interaction of the oil with the constructional materials (the copper of the windings, the iron of the tank, the core etc.) is considered. Acriterion of dangerous contamination of the coil insulation of the windings by metal-containing colloidal particles is proposed, namely, 3% of the mass content of copper and iron in it, which, if exceeded, may serve as a basis for recognizing the state of transformers, autotransformers and shunting reactors at a voltage of 110 kV and above the limit. It is shown that filters for continuously cleaning the oil play a considerable role in prolonging the life of transformer equipment.

The results of a measurement of the contamination of the oil in 66 transformers by metal-containing colloidal particles, formed as a result of the interaction of the oil with the structural materials (the copper of the windings, the iron of the tank and core etc.), and also the results of measurements of the optical turbidity of the oil in 136 transformers when they were examined at the Power Engineering Research and Development Center Company are presented. Methods of determining the concentration of copper and iron in transformer oil are considered. The limiting values of the optical turbidity factors, the copper and iron content are determined. These can serve as a basis for taking decisions on whether to replace the silica gel of the filters for continuously purifying the oil of power transformers and the shunting reactors in addition to the standardized oil contamination factors, namely, the dielectric loss tangent and the acidity number of the oil.

The effect of ionizing radiation on the molecular weight characteristics and ability to be dissolved of high-molecular, high-viscosity sulfite cellulose has been investigated.