Search

New photosensitive polymeric film composites based on oligo-N-glycidylcarbazole oligomer with azobenzene dyes as additives (azobenzene derivatives with a glycidyl group in their structure) were obtained and investigated. It was shown that the created composites exhibit photovoltaic properties when they are irradiated in the absorption region of the azobenzene dye. The mechanism and the photovoltaic effect in the investigated composites are discussed.

The recording media for polarization holography based on azobenzene polymers are obtained by polymer-analogous transformations of polymethacrylic acid and its copolymers with alkyl methacrylates. Their informational properties were investigated when recording holograms of a plane wavefront. It has been found that the recording and relaxation times of holograms are approximately the same. They are defined mainly by the processes of trans-cis-isomerization of azobenzene groups without formation of surface relief of the polymeric film. The efficiency of the trans-cis-isomerization process decreases, if a heavy substituent is present in the azobenzene chromophore. These results are of practical interest in the choice of photosensitive materials for holographic recording media with optimal information characteristics.

The article considers the general concept of corrosion in accordance with GOST 5272–68 “Metal Corrosion”, the classification of the corrosion process, the stages of corrosion as energy function of the flow path of the corrosion process, the main indicators of the corrosion process. According to the forecasts of the International Monetary Fund and Focus Economics, the amount of funds that will be spent on counteracting corrosion and its consequences in selected industrialized countries has been estimated. The growth of funds invested in the counteracting the effects of metal corrosion in the Russian Federation for 2016–2019 is presented in the form of a diagram. The substantiation of the use of zirconium as a structural material for the shell of fuel rods has been fulfilled. The values of the thermal neutron absorption cross sections for various elements serving as structural elements for the core of a nuclear reactor are presented. Factors influencing the choice of alloying elements and their percentage in various alloys (Zr-2, Zr-4, ZIRLO™, M5®), which are the special development that reduce the corrosion rate, are also considered. The composition and mechanical properties of E110 and E635 alloys, which were used as materials for the fuel rods shell in the core of WWER-1200 reactors at the Belarusian NPP, are considered as well. The behavior of zirconium alloys E110 and E635 in the core is analyzed. The main factors that make a significant contribution to the corrosion process in actual operating conditions of zirconium alloys as fuel rods shell have been identified. The existing methods of preliminary special processing of fuel rods shells stored in the air for a long time before their receipt for assembly are presented. The structure of the oxide on the shells of alloys E110 and E635 oxidized in an autoclave is demonstrated.

Based on polymers with the addition of azo dyes as chromophores and azopolymers with the same covalently linked chromophores, recording media for polarization holography are created and their properties are studied when recording holograms of a plane wave front with parallel and perpendicular polarization of recording rays. It is found that the diffraction efficiency and the storage time of holograms are much longer in recording media with films of azo polymers in comparison with polymeric solid solutions of azo dyes. In the latter case, the energy of light is spent only for the trans–cis isomerization of azo dye molecules during exposure of holograms and the polymer chains do not undergo deformation with the formation of a surface relief in the polymer film. Therefore, it is preferable to use recording media based on solid solutions of azo dyes in dynamic polarization holography.

The effect of halogens in carbazolyl-containing oligomers on the information properties of recording media in the photothermoplastic method of recording holograms is studied. An increase of photosensitivity was observed for such media with halogens present in their composition. It was shown by photoactivated electron paramagnetic resonance that the lifetime of the photogenerated charge pairs is increased in the presence of halogens. This is due to the increased probability of photogeneration of charge pairs in the triplet state for the modified oligomers compared with their analogs. It is presumed that modification of the photoconductive polymers with halogens is one way of increasing their photosensitivity and for other practical applications (photovoltaics, molecular electronics).

Recording media for polarization holography have been created on the basis of 4-((2-bromo-4-nitrophenyl)diazenyl)phenyl methacrylate copolymers, and the properties during that they manifest during recording of holograms of a plane wavefront have been studied. It has been found that the hologram recording rate at room temperature is the same for the perpendicular and parallel polarization of recording rays and the hologram relaxation rate is higher in the case of perpendicular polarization orientation of recording rays. It has been shown that the diffraction efficiency of holograms does not exhibit a monotonic relation with the film softening temperature.

To create radio engineering control systems for non-polar gases transported through gas pipelines, especially natural gases or gases associated with oil production, it is necessary to take into account the influence of humidity on the characteristics of gases, especially in the decimeter and centimeter wavelength ranges. A methodology has been developed for the effect of humidity on the relative dielectric constant of non-polar gases.

A recording medium based on a novel copolymer of 4-((4-hydroxyphenyl)diazenyl)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one with nonyl methacrylate is created, and the possibility of its use for polarization holography is investigated. It is shown that, for films based on this copolymer, holograms can be recorded without special heating due to a fairly low softening temperature. The recorded holograms are characterized by low noisiness.

In the films of copolymer 4-((2- nitrophenyl)diazenyl)phenylmethacrylate with octylmethacrylate the holograms of the plane wave front were registered for parallel and orthogonal orientations of polarization vectors of the object and reference light beams. The diffraction efficiency of the holograms is higher when pulsed exposure during holographic recording is used instead continuous exposure. After the holograms registration, the diffraction efficiency of the reconstructed holographic image can be significantly increased by charging the film surface in the corona discharge. This effect is explained by strengthening the modulation of the surface relief of the films.

Peculiarities of the polarization holographic recording in the samples with the films of copolymer poly[4-((2-nitrophenyl)diazenyl)phenylmethacrylate-co-octylmethacrylate] with free surface and in the sandwich-structures with solid covering layer are investigated. Time of the holographic recording and its storage is less in the sandwich-structures. It was concluded, that in the sandwich-structures, geometric relief of the film surface does not appear during the recording.

The properties of composites for the photothermoplastic recording of holograms based on cooligomers with common naphthyl and different (fluorenylidene, anthracenyl) fragments were investigated. It was found that increase in the amount of halogen substituent Clin the cooligomer reduces the diffraction efficiency of the holograms. The possible practical application of such recording media was demonstrated.

New photosensitive polymeric film composites based on oligomer containing ferrocenyl and carbazolyl fragments doped with symmetric polymethine dye are synthesized. Their photoelectric properties are investigated. Photovoltaic properties of these composites are detected. The mechanisms and peculiarities of the photovoltaic and photodielectric effects are discussed.

The paper discusses findings of the experimental study of the tribological characteristics of hydraulic oils HVLP-46, MGE-46d, MGE-46l, VO, ZF-46, and HLP-46. A technique is developed for studying the antiscoring properties of hydraulic oils based on measurements of contact resistance for the shaft-partial insert geometry (multiple contact). It is shown that contact resistance is a more sensitive parameter compared to the coefficient of friction.

The photothermoplastic medium based on the films of photosensitive polymeric composites with semiconductor properties is developed for application in optical information recording and storage, in holographic interferometry, as well as for medical purposes. This medium was used in the modified holographic device for determination of changes of the refractive index of homogeneous and inhomogeneous liquid objects. The technique and holographic equipment were modified by employing the specially developed and produced transparent cuvette of special shape and the phase shifting interferometry method. Experimentally demonstrated precision of the measurements is not less than 10-5.

Unusual multimodal kinetics of diffraction efficiency in the cycle of hologram recording and erasing were observed in the recording media for the holographic photothermoplastic technique. It was shown that this effect is caused by competition between the simultaneous development of regular and random "frosty" surface reliefs of the photoconducting polymer film during the hologram development. The mechanism explaining the decrease of the maximal diffraction efficiency as compared to its calculated value is discussed.

Rhombohedral and monoclinic modifications of the Li3In2(PO4)3 compound have been studied by X-ray diffraction, infrared (i.r.) analysis, Raman light scattering, differential thermal analysis (DTA), differential scanning calorimetry (DSC) and impedance spectroscopy, in a wide temperature range of 290–600 K. Analysis of the data allows the suggestion that the superionic phase transition, observed in these materials in the temperature interval 370–385 K, belongs to Faraday type phase transformations. PO4 tetrahedra, which are a partition of the (In2P3O12) 300 3− rigid skeleton, have been found deformed. This seems to be due to an ordered lithium ion-vacancy distribution in the low temperature, non-superionic, polymorphs. With increasing temperature these deformations disappear. This disappearance can be caused by a decrease of the correlation length of the lithium ion-vacancy order.

An inductive coupling dc-SQUID has been developed which is a thin-film structure containing an input coil, a SQUID proper and a groundplane. The SQUID parameters are sensitive to the thicknesses of insulating layers between these components. The SQUID can provide a high coupling constant between the input coil and SQUID loop.