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In the second part of the review, based on the analysis of the world experience in conducting climate tests, the main development trends related to new applications of materials, their compatibility, modeling of loading cycles, acceleration of climate tests, the impact of climate gradients, taking into account the level of climate factors in a particular area with a minimum resolution, climate change, new methods for assessing the climatic resistance of materials and biolo-gical impact factors are identified. The relevance of complex tests of materials for climatic and biological resistance with the use of methods for predicting their properties is shown.

In the first part of the review, based on the analysis of world experience in conducting climate tests, the main development trends related to the development of new materials are identified, and it is Shown that in parallel with the development of new materials, appropriate methods of climate testing should be developed taking into account previous experience. It is shown that to assess and predict changes in properties of materials over a long operating life tests of materials are required to conduct accelerated methods of building mathematical models of processes of degradation of their properties under the given climatic and operating factors.

The founder of the science of protecting materials from corrosion, aging and bio-damage in Soviet Russia is Georgy Vladimirovich Akimov, who created the infrastructure for climate testing of materials and products. Currently, his students and followers have discovered new directions for the development of climatic and microbiological tests – these are studies of the preservation of the properties of materials in complex technical systems under the influence of climatic factors, mold fungi, bacteria and operational loads using the most modern methods at the sites of the created network of climate test stations, as well as using modern regulatory documentation.

The development of methods for assessing the creep of polymer composite material depending on the current loads and climatic factors is an urgent task. The binder made of polymer reactoplastics is an amorphous structure and is capable of plastic deformation – creep under the action of a long-term and insignificant static load. Methods of accelerated and full-scale testing of binder samples are proposed in order to determine the degree and time of change in the shape of parts depending on the properties of the material and the current climate factors.

The paper considers the options for replacing the electroplated single-layer toxic cadmium coatings with zinc-based compositions, as well as multi-layer coatings. Their tribological characteristics and tendency to hydrogenation of the protected metal during coating and operation are considered. Conclusions are drawn about the shortcomings of existing technologies and promising directions of research in this area. Thus, the most preferred composition for replacing a cadmium coating is a nickel-zinc coating with nickel content of 12% (by weight), but a tin-zinc coating has the lowest value of the coefficient of friction, close to the value for cadmium.

The article considers the possibility of increasing the efficiency of chemical reagents by treating inhibited solutions with a magnetic field. It is shown that a various method for generating the magnetic field has a different effect (Some positive some negative). The best results can be achieved with anti-scale magnetic treatment using permanent magnets. Modified inhibitors (after magnetic treatment) have enhanced protective effectby their adsorption capacity with respect to metal increases.

Background It is known that electrochemical corrosion of carbon and low-alloyed steels in ground electrolytes occurs with hydrogen depolarization. In this case, the volume released due to the assimilation of electrons during the cathode process of molecular hydrogen is equivalent to the mass of the dissolved metal. If this process occurs under the peeling-off insulation of the cathode-protected surface of the gas pipeline laid in the soil, hydrogen diffuses into the soil located above the pipe and is sorbed by it. Later, upon reaching a certain concentration of hydrogen in the soil layer, it begins to desorb into the atmosphere over the route, which can be used to identify the presence and intensity of the corrosion process under peeling insulation by measuring the flow of hydrogen using special highly sensitive equipment. Aims and Objectives The aim of the work was to quantify the sorption of molecular hydrogen by the soil, depending on the thickness of its layer. The following tasks were solved: to determine the dependence of the concentration in the soil of hydrogen evolved during cathode depolarization of its layer thickness; to establish the effect of soil moisture on the sorption capacity of hydrogen. Methods An original method was used to study the sorption of hydrogen by the soil on a specially developed laboratory stand. This method allows us to identify the presence of a corrosion process on steel by registering the threshold values of hydrogen emission during cathode depolarization on the metal surface under the soil layer. Results Studies conducted with the help of the developed laboratory stand showed that soil samples actively adsorb hydrogen. Moreover, after a certain incubation period, the duration of which depends on the thickness of the soil layer, there comes a state of «transparency» for hydrogen: just as much hydrogen is sorbed by the soil from the side of the pipe wall as it desorbs into the atmosphere over the area chosen for measurements trails. The moisture content of the soil has a significant effect on the sorption capacity of hydrogen: its maximum amount is contained in the soil with zero humidity. When the soil is moistened, both air and sorbed hydrogen are simultaneously expelled from it.

Background The corrosion process under the influence of the soil electrolyte pipeline on the metal is accompanied by the release of hydrogen under the peeling insulation during cathodic depolarization. The volume of molecular hydrogen released due to the assimilation of electrons is proportional to this loss of metal mass. The upward flow of hydrogen due to the physical characteristics of this gas has a high penetrating ability with respect to the insulation materials and the structure of most soils and, as a result, without any difficulties moves over the center of pre-film corrosion through the soil, comes to its surface, where it can be registered with an appropriate detector both qualitatively and quantitatively. With this approach to monitoring under-film corrosion (UFC), there is no need to drill on the surveyed section of the pipeline. An analysis of the intensity of the hydrogen flow over the soil allows one to establish the location of the developing corrosion defect and assess the possibility of further operation of the pipeline without repair and restoration work. Aims and Objectives The aim of the work was to assess the possibility of determining the location of the PPC center by the recorded concentration of hydrogen over the soil surface without pitting. The following tasks were solved: to carry out test tests of the practical effectiveness of the developed method and the pilot complex for detecting hydrogen released during cathodic depolarization; establish the location of the corrosion center by the excess of hydrogen concentration over the background value. Methods A specially developed method for determining the concentration of hydrogen over the route of the main gas pipeline was used. This method and the pilot complex for its implementation make it possible to identify with high reliability the presence of a corrosion process on the surface of the gas pipeline by registering threshold values of hydrogen emission during cathodic depolarization on the metal surface under a layer of exfoliating protective coating and soil. Results Studies conducted with the help of the developed pilot complex of non-destructive testing of UFC confirmed the real possibility of reliable registration of the hydrogen flow on the soil surface above the axis of the gas pipeline. Using the software of this complex made it possible to establish the dependence of the hydrogen concentration on the surface on the duration of the measurements. It has been shown that over areas with a developing UFC center, the concentration of hydrogen exceeds the measured background value by more than an order of magnitude. The results of the control pit survey confirmed the presence of a corrosion lesion and the parameters of its localization on the pipe surface.

During the last several years, the measurements of neutron-induced fission cross-sections of actinides and stable isotopes have been performed at the GNEIS facility. At present moment, the new series of experiments for measurements of fission cross-section ratios relative to 235 U have been began for 240 Pu, 243 Am and nat W in a wide energy range of incident neutrons from 1 MeV to 200 MeV. The measurements were performed using the multiplate ionization chamber and time-of-flight technique. The first results of this measurement in case of 240 Pu and 243 Am are presented in comparison with the other data.

The description of an experimental set-up for neutron multiplicity measurements and its specific data processing procedures are presented together with some results for 252 Cf ( sf ) . With this experimental set-up the light and heavy fission fragment kinetic energies for every fission event can be registered simultaneously with the number of prompt neutrons emitted by each of the complementary fission fragments. The proposed data processing makes it possible to perform the reconstruction of pre-neutron fission fragment masses and kinetic energies as well as the initial neutron multiplicity distribution.

Fission cross section ratios of 233U, 238U, 232Th, 239Pu, 237Np, natural Pb and 209Bi to 235U have been measured in a wide energy range of incident neutrons from 1 MeV to 200 MeV using a time-of-flight technique at the neutron spectrometer GNEIS based on the 1-GeV proton synchrocyclotron of PNPI. For actinide targets, the threshold cross section method and evaluated data below 14 MeV were used for normalization of the shape measurement data, while the evaluated and recommended fission cross sections of 235U were used to convert the ratio data to absolute fission cross sections. For Pb and Bi targets, an absolute normalization of the measured cross section ratios has been done using the thickness of the targets and detection efficiencies.

The description of an experimental set-up for the study of the excitation energy distribution of fission fragments by means of coincident measurement of fission neutrons is presented. For every fission event the kinetic energy and mass of both fragments are registered simultaneously with the number of prompt neutrons emitted by each of the complementary fission fragments. With this set-up, the fission fragments are detected by a twin ionization chamber and the neutrons - by two large Gd-loaded liquid scintillator tanks.

The number of prompt neutrons emitted in the fission event have been measured separately for each complementary fragment in coincidence with fragment mass and kinetic energies in spontaneous fission of 252Cf, 244Cm and 248Cm. Two high efficient Gd-loaded liquid scintillator tanks were used for the neutron registration. Approximately 3 106 fission events coincident with prompt neutron emission have been accumulated for each isotope. The mean neutron multiplicity, the dispersion and the covariance of the multiplicity distributions have been obtained as a function of fission fragment mass and kinetic energy. The neutron multiplicity data have been corrected for neutron registration efficiency, background and pile-up. Dependencies of the moments of the multiplicity distributions on the fragment mass and total kinetic energy for different mass bins, as well as mass and total kinetic energy distributions of the fission fragments are presented, discussed and compared for the different isotopes investigated. The ...

The neutron‐induced fission cross‐section ratios relative to 235U has been measured for 240Pu, 243Am and natW in a wide energy range of incident neutrons from 1 MeV to 200 MeV at the GNEIS facility. The measurements were performed using the multiplate ionization chambers and time‐of‐flight techniques. The results obtained in this measurement are presented in comparison with the other data.

Neutrons emitted in fission events were measured separately for each complementary fragment in correlation with fission fragment energies. Two high‐efficiency Gd‐loaded liquid scintillator tanks were used for neutron registration. Fission fragment energies were measured using a twin Frisch gridded ionization chamber with a pinhole collimator. The neutron multiplicity distributions were obtained for each value of the fission fragment mass and energy and corrected for neutron registration efficiency, background, and pile‐up. The dependency of these distributions on fragment mass and energy for different energy and mass bins as well as mass and energy distribution of fission fragments are presented and discussed.

The method of the “shape” measurement was realized using an impulse spallation source of the synchrocyclotron at Leningrad Nuclear Physics Institute. The fission cross section ratios 238U/235U and 232Th/235U were measured as a function of neutron energy from 1 to 100 MeV. A multiplate methane gas ionization chamber located at a 50 m flight path was used to scan by time the fission count rates for all the three samples simultaneously. The data were compared with those obtained using linear accelerator.

A description of GNEIS- the Gatchina neutron time-of-flight spectrometer at the 1 GeV proton synchrocyclotron-is given together with its basic parameters, as well as a comparison with other modern pulsed neutron source facilities. The integral neutron yield from a lead target is 3 × 10 14 n s . The spectrometer has five flight paths and a data acquisition system equipped with a few autonomous measuring stations. Some results of the (n, γf) experiments and neutron capture cross section measurements are presented to illustrate the facility's performance.

Experimental results of systematic studies of the space parity violation effect in heavy nucleus fission induced by transversally polarized monochromatic neutrons with the energies less then ~ 2 eV have been presented. Modern explanations of the results obtained and perspectives of the further investigations are discussed.