Search

To date, the possibilities of using metal oxide particles in various fields have been developed [1]. At the same time, their characteristics largely depend on the method of preparation, which usually determines their structure, size, and physicochemical properties [2]. Among the methods for obtaining nanosized particles, one can single out methods of green synthesis [3], electrochemical [4], electropulse [5], and plasmachemical [6] synthesis based on the reduction or oxidation of metal ions in solutions under favorable conditions, followed by aggregation of nanoparticles. The purpose of this work is to analyze the technology for the synthesis of cobalt oxide compounds using contact nonequilibrium low-temperature plasma and to determine the directions for its further improvement. The object of the study was the process of obtaining particles of cobalt oxide using contact non-equilibrium low-pressure plasma during the processing of a liquid medium. The study was carried out using laboratory equipment and software modules of the HSC Chemistry 5.11 package. To find the preliminary conditions for the formation of interphase boundaries, diagrams were used in the coordinates of the E-pH potential of the aquatic environment (Pourbaix diagrams). It has been established that, depending on the initial state of Co(OH)2 in solution, the mass fraction of oxygen in the precipitate can change. In this case, the addition of hydrogen peroxide leads to a decrease in the proportion of hydroxide compounds in sediments. X-ray phase analysis showed the presence of CoO, CoOOH, Co3O4, β-Co(OH)2, Co in dry sediments. It has been established that the particle sizes lie in the range of 10 – 110 nm. The micrographs confirm the agreement between the calculated values and the experimental data. The phase composition of the deposit is influenced by the following factors: current density and anion concentration, process temperature. Increasing the temperature increases the diffusion coefficient but requires a higher current density to produce a powder. It has been established that a decrease in the liquid layer contributes to an increase in the yield of oxide compounds. The results of the analysis allow us to conclude that when using the technologies of plasma-chemical processing of liquid media to obtain compounds of the ultra- and nanoscale range, it becomes necessary to choose the parameters that are optimal for this process. The results of the analysis allow us to conclude that this technology can be optimized by controlling the initial pH of the solution; use of the spent solution in a container with the initial solution for its acidification; refinement of the reactor block for treating the solution in a film mode or close to it; choice of rational parameters for sludge drying. Laurent S., Boutry S., Muller R. N. Metal oxide particles and their prospects for applications //Iron oxide nanoparticles for biomedical applications. – Elsevier, 2018. –P. 3-42. Wang L. et al. Rational design, synthesis, adsorption principles and applications of metal oxide adsorbents: a review //Nanoscale. – 2020. – Vol. 12. – №. 8. – P. 4790-4815. El Shafey A. M. Green synthesis of metal and metal oxide nanoparticles from plant leaf extracts and their applications: A review //Green Processing and Synthesis. – 2020. – Vol. 9. – №. 1. – P. 304-339. Lawrence M. J., Kolodziej A., Rodriguez P. Controllable synthesis of nanostructured metal oxide and oxyhydroxide materials via electrochemical methods //Current Opinion in Electrochemistry. – 2018. – Vol. 10. – P. 7-15. Gan Z. et al. A laser and electric pulse modulated nonvolatile photoelectric response in nanoscale copper dusted metal‐oxide‐semiconductor structures //Advanced Electronic Materials. – 2018. – Vol. 4. – №. 11. – P. 1800234. Shamanin I. et al. Plasmachemical synthesis and evaluation of the thermal conductivity of metal-oxide compounds for prospective nuclear fuel //Journal of Physics: Conference Series. – IOP Publishing, 2019. – Vol. 1145. – №. 1. – P. 012057.

Recently, the interest of researchers in nanodispersed oxides of monovalent and bivalent copper, ferrum, cobalt, nickel, and chromium has significantly increased. At the same time, interest in their micro- and nanosized particles is due, first of all, to a wide range of possibilities for their practical application. Today it is possible to use Cu2O, CuO in the creation of new catalysts for various industrial processes, as a filler for varnishes and paints, antiseptics. Cu2O is used in the production of galvanic cells, other fields of technology, etc. [1]. At the same time, the characteristics and variants of their practical application largely depend on the method of preparation, which usually determines their structure, dimensions, physical and chemical properties, etc. [2]. Among the methods for obtaining micro- and nanoparticles, large groups form the methods of chemical, electrochemical, electropulse, and plasma-chemical synthesis, based on the processes of reduction or oxidation of metal ions in solutions, depending on the conditions. Each of these groups has its advantages and disadvantages, but the use of the plasma-electrochemical method (using the treatment of aqueous media with contact low-temperature non-equilibrium plasma (CNP) of reduced pressure) makes it possible to use the advantages of each of the groups [3-5]. However, in this case, it becomes necessary to establish the relationship between the synthesis parameters and the phase composition and morphology of the resulting particles. At the first stage, Pourbaix diagrams were constructed corresponding to the conditions of synthesis in a plasma reactor, and voltammograms were obtained, which made it possible to evaluate the effect of pH synthesis on the composition of products. The morphology of the particles was also studied depending on the current strength of the process at the same initial concentration of Сu2+ in an aqueous solution. The use of X-ray phase analysis and electron microscopy made it possible to evaluate the composition and dimensional characteristics of dry sediments. Thus, at the process current I=200-250 mA, particles were obtained, consisting of intergrowths of crystals, the size of which did not exceed 30 μm, at I=140-200 mA crystals up to 15 μm were obtained, at I=80-140 mA the average crystal size did not exceed 5 µm. The structure of the particles was also established: the largest particles were represented mainly by intergrowths of smaller crystals. It is obvious that the formation of numerous crystallization centers with the simultaneous intense evolution of hydrogen contributes to the fact that the rate of crystal growth at the cathode decreases. At higher current strength parameters, the growth of individual crystals is observed (mainly in the form of octahedrons and cuboctahedrons, the size of which reaches 10-15 μm. A decrease in the current strength leads to a decrease in the particle size - both individual crystals and their intergrowths, which in this case are predominantly octahedral structures, the largest of which are 1–2 µm, and the smaller ones are 100–200 nm. The results of X-ray diffraction analysis show that under the given conditions for the formation of a deposit, the surface of the formed particles consists mainly of Cu2O. On the basis of the conducted studies, it can be noted that the size of the precipitate particles obtained can vary within a fairly wide range. In this case, a change in the process parameters, especially a decrease in the process current, leads to a decrease in the size of the formed particles and an increase in the deposit uniformity, which is confirmed by the results of electron microscopic studies of the synthesized cathode deposits. This makes it possible to control the particle synthesis process by adjusting the parameters of the plasma-chemical processing process, which, due to its simple design, does not cause difficulties and, along with the possibility of using highly diluted solutions, is an advantage of this method.

The article deals with the process of foreign language communicative competency development at a technical university within the work of the linguistic club "Intelligent" of Lenin Ivanovo State Power Engineering University. The pedagogic conditions and methodological principles are explained. It is proved that the structure and variation of the linguistic club activities promotes development of the key components of foreign language communicative competency: linguistic, verbal, sociolinguistic, sociocultural, strategic, discursive competences. It is concluded that the linguistic club is an important component of teaching a foreign language at a technical university as it gives the opportunity for improvement for students of different levels, contributes to students' raising foreign language learning motivation and creative potential realisation. During the preparation for the events students' professional and personal competences are also developed.

Hypothesis/aims of study. An integrated evaluation of the effectiveness of pelvic organ prolapse (POP) treatment in women requires a consistent interpretation of the criteria of treatment satisfaction. The aim of this study was to specify surgical treatment satisfaction in patients with POP. Study design, materials, and methods. Surgical treatment was performed in 486 patients with POP stages II–IV. In 12 months, a patient survey (using a 1-5-point scale) evaluated the level of treatment satisfaction, reasons for lowered self-reported satisfaction, and respondents’ ambivalence regarding treatment results. Results. One-year post-surgical treatment of POP stages 0–I are observed in 80.9% of patients. Full satisfaction (5 points) was self-reported by 61.1% of patients, 28.6% of patients indicated partial satisfaction (3–4 points), and 10.3% of patients indicated treatment dissatisfaction (1–2 points). Post-surgery stage of POP is weakly correlated with self-reported treatment satisfaction (r = –0.39; p < 0.0001). Most common reasons for lower self-reported satisfaction were the emergence of new issues, fear of pathology recurrence, urinary incontinence, and pain. Five patients (1.0%) indicated that their condition “became much worse” after the surgical treatment. Conclusion. The treatment satisfaction range is variable. It is necessary to consider a variety of clinical, deontological, and psychological factors in the analysis of surgical POP treatment satisfaction spectrum.

Positron beams, both polarized and unpolarized, are identified as essential ingredients for the experimental programs at the next generation of lepton accelerators. In the context of the hadronic physics program at Jefferson Lab (JLab), positron beams are complementary, even essential, tools for a precise understanding of the electromagnetic structure of nucleons and nuclei, in both the elastic and deep-inelastic regimes. For instance, elastic scattering of polarized and unpolarized electrons and positrons from the nucleon enables a model independent determination of its electromagnetic form factors. Also, the deeply-virtual scattering of polarized and unpolarized electrons and positrons allows unambiguous separation of the different contributions to the cross section of the lepto-production of photons and of lepton-pairs, enabling an accurate determination of the nucleons and nuclei generalized parton distributions, and providing an access to the gravitational form factors. Furthermore, positron beams offer the possibility of alternative tests of the Standard Model of particle physics through the search of a dark photon, the precise measurement of electroweak couplings, and the investigation of charged lepton flavor violation. This document discusses the perspectives of an experimental program with high duty-cycle positron beams at JLab., Comment: 18 pages, 7 figures This version superseeds the previous version which scientific content was decomposed into several more elaborated articles. All of these articles will be collected in the EPJ A Topical Issue about "Positron beam and physics at Jefferson Lab (e+@Jlab)"

The priority development direction of the mushroom industry is in line with the provision of the updated Doctrine of Food Security of Russia. The paper analyzes the production volumes and the market of mushroom products for 2014–2019 according to the import substitution program. Demand exceeds supply and has prospects for further development. The main factors and difficulties hindering the innovative development of the mushroom industry are identified. The mushroom industry depends on the import of compost and substrate. The authors indicated the advantages of the innovative development of mushroom production. The innovative development of the Russian mushroom industry solved several problems at once: import substitution, support of farms, the development of related industries and technology suppliers, the development of exports, and the maintenance of a healthy diet. In the future, the mushroom industry will allow the development of the food, pharmaceutical, and furniture industries. The mushroom industry combines many sciences: microbiology, biochemistry, botany, mycology, microelectronics, etc. In order to solve the personnel issue, it is proposed to apply for specialized training programs in Germany (program “Farm Management”—field commanders) or the project “Agrokebet.”

A modern manufacturing enterprise requires constant modernization of the tools and technologies used in production. The use of innovative equipment contributes to improving product competitiveness. An increase in the population, changing tastes, growing food demand, and the development of science and technology cause the rapid development of the domestic food industry. Particular attention is paid to quality indicators in the production and sale of ready-to-eat food. Currently, non-price factors largely influence the results of food sales in the Russian market. The development of modern production increases its unit costs, amplifying the need to use innovative equipment in production, which leads to cost savings. The paper reflects the economic rationale for using the “FoodScan” production analyzer in the meat industry. Its implementation in the production will allow to quickly and reliably determine the chemical composition and calorific value of the edible part of the meat in accordance with the quality standards and technological parameters for slaughtered animals of all types. It will replace about ten laboratory employees and improve the quality and speed of measurements, leading to a reduction in production costs for processing raw meat and the cost of finished meat products. The assessment of one-time and current costs was carried out on the example of the meat processing plant “Dmitrogorsky Meat Processing Plant” LLC. The total operating costs for assessing the quality of raw meat and finished meat products will be reduced by 9.3 million rubles. It is possible to save 61% or 2,888 person-hours annually for laboratory research. The annual economic effect, taking into account the standard ratio of the relative efficiency of capital investments, will amount to 7.7 million rubles.

We propose to use the High Momentum Spectrometer of Hall C combined with the Neutral Particle Spectrometer (NPS) to perform high precision measurements of the Deeply Virtual Compton Scattering (DVCS) cross section using a beam of positrons. The combination of measurements with oppositely charged incident beams is the only unambiguous way to disentangle the contribution of the DVCS $$^2$$ term in the photon electroproduction cross section from its interference with the Bethe-Heitler amplitude. This provides a stronger way to constrain the Generalized Parton Distributions of the nucleon. A wide range of kinematics accessible with an 11 GeV beam off an unpolarized proton target will be covered. The $$Q^2-$$ dependence of each contribution will be measured independently.

We report a measurement of the antineutrino rate from the fission of U235 with the STEREO detector using 119 days of reactor turned on. In our analysis, we perform several detailed corrections and achieve the most precise single measurement at reactors with highly enriched U235 fuel. We measure an IBD cross section per fission of σf=(6.34±0.06[stat]±0.15[sys]±0.15[model])×10-43 cm2/fission and observe a rate deficit of (5.2±0.8[stat]±2.3[sys]±2.3[model])% compared to the model, consistent with the deficit of the world average. Testing U235 as the sole source of the deficit, we find a tension between the results of lowly and highly enriched U235 fuel of 2.1 standard deviations.

The effective functioning of the agro-industrial complex (AIC) mostly depends on the structure and size of the costs of the formation and operation of the engineering production base. In agriculture, the agronomic terms of technological operations, the complexity of production, the quality of the resulting product, and its cost depend on the state of the technical means. A significant share of the cost of agricultural products is the cost of operating machinery and equipment. The optimization of these costs is based on a rational distribution of repair and maintenance work between the levels of the repair base of the regional agro-industrial complex. The paper focuses on the methodology of cost planning and identifies the technologies for optimizing the distribution of repair work. The task of optimizing the distribution of repair and maintenance work, taking into account the specialization of the repair and maintenance base of the district, is to take down the total reduced costs by type of work. The objective function that allows solving the problem of optimizing the process of servicing equipment is proposed. The cost limits for the main types of repair and maintenance work are determined by the example of the economy of the Rostov region. The techniques for indexing costs in planning, which will more accurately reflect costs taking into account inflationary processes and other economic changes, are proposed. The distribution of the repair work by enterprises of various levels has been completed. The obtained results allow us to substantiate the production parameters and structure of the repair and maintenance facilities of a specific administrative region. The creation of information databases, scheduling, and aggregation of data flows for regulating end-to-end production processes on the current state of agricultural machinery, and upcoming periodic maintenance will increase the speed of response to failures and machine downtime, increase labor productivity, thereby becoming the basis for making operational decisions.

International audience; The CEBAF Large Acceptance Spectrometer for operation at 12 GeV beam energy (CLAS12) in Hall B at Jefferson Laboratory is used to study electro-induced nuclear and hadronic reactions. This spectrometer provides efficient detection of charged and neutral particles over a large fraction of the full solid angle. CLAS12 has been part of the energy-doubling project of Jefferson Lab’s Continuous Electron Beam Accelerator Facility, funded by the United States Department of Energy. An international collaboration of 48 institutions contributed to the design and construction of detector hardware, developed the software packages for the simulation of complex event patterns, and commissioned the detector systems. CLAS12 is based on a dual-magnet system with a superconducting torus magnet that provides a largely azimuthal field distribution that covers the forward polar angle range up to 35 ∘ , and a solenoid magnet and detector covering the polar angles from 35° to 125° with full azimuthal coverage. Trajectory reconstruction in the forward direction using drift chambers and in the central direction using a vertex tracker results in momentum resolutions of < 1% and < 3%, respectively. Cherenkov counters, time-of-flight scintillators, and electromagnetic calorimeters provide good particle identification. Fast triggering and high data-acquisition rates allow operation at a luminosity of 1035 cm −2 s −1 . These capabilities are being used in a broad program to study the structure and interactions of nucleons, nuclei, and mesons, using polarized and unpolarized electron beams and targets for beam energies up to 11 GeV. This paper gives a general description of the design, construction, and performance of CLAS12.

Stress protectors (adaptogens) are among the most important factors that regulate growth processes at all stages of plant development. This article presents results of field studies of the effect of new synthetic plant growth regulators of stress protectors (adaptogens) on the elements of productivity and yield of spring oats of the Skakun variety. The obtained results during the research showed that all the studied derivatives of peredazinones are adaptogens and they contribute to an increased productivity and increased yield of spring oats. We studied the effect of pre-sowing treatment of seeds with new synthetic plant growth regulators of stress protectors on the quality indicators of cereal production of Skakun oats (protein, starch and amylolytic enzymes content in the cereal). Pre-sowing treatment of oat seeds increases the amount of protein in the cereal up to 15%, starch – up to 25%, amylase – up to 20%. We proved the ability of stress protectors to minimize the negative impact of heavy metals (lead, zinc) on agrophytocenoses, which will make it possible to obtain environmentally friendly cereal products when cultivating oats in anthropogenically polluted areas of the Saratov Oblast.

Sustainable fodder production, feeding capacity, and high animal productivity are the basis of effective animal husbandry. Nutritious, high-quality feed additives and vitamin premixes have been delivered to Russia from Denmark, France, Belgium and other countries for many years. However, it is possible to improve the feeding value of grains and their accessibility for animals through innovative solutions in using balanced concentrates or dry feed technologies. Regarding current conditions, it is only innovation-oriented development of dairy farming that will reduce milk production cost, ensure profit increase, and consequently production profitability, by means of technological, organizational and economic innovation, an optimal combination of primary, auxiliary and service production. The article discusses new approaches to organizing the use of grain fodder on farms enabling them to provide dairy cattle with more nutritious feeds, realise animal genetic potential, reduce feed costs by about 7-10%, thus improving animal husbandry profitability. An organizational and technological innovation has been proposed in the case of Limited Liability Company «Agribusiness Firm «YUMA» in Krasnodar Territory. Introducing feed preparation unit extruder KMZ-2U will increase milk production profitability from 11 to 16.3%.

The STEREO experiment measures the electron antineutrino spectrum emitted in a research reactor using the inverse beta decay reaction on H nuclei in a gadolinium loaded liquid scintillator. The detection is based on a signal coincidence of a prompt positron and a delayed neutron capture event. The simulated response of the neutron capture on gadolinium is crucial for the comparison with data, in particular in the case of the detection efficiency. Among all stable isotopes, $^{155}$Gd and $^{157}$Gd have the highest cross sections for thermal neutron capture. The excited nuclei after the neutron capture emit gamma rays with a total energy of about 8 MeV. The complex level schemes of $^{156}$Gd and $^{158}$Gd are a challenge for the modeling and prediction of the deexcitation spectrum, especially for compact detectors where gamma rays can escape the active volume. With a new description of the Gd(n,${\gamma}$) cascades obtained using the FIFRELIN code, the agreement between simulation and measurements with a neutron calibration source was significantly improved in the STEREO experiment. A database of ten millions of deexcitation cascades for each isotope has been generated and is now available for the user., Comment: 5 pages, 3 figures

Many agricultural organizations are searching for innovative solutions in the engineering equipment of livestock premises in order to maintain an optimal microclimate in them. With stable keeping, the productivity of animals directly depends on the nutritional value of feed, a certain state of the air, temperature and humidity. The article provides a brief analysis of the indicators of economic activity of Temp LLC in the Kaliningrad region, whose main activity is dairy farming. A reduction in the productivity of dairy livestock and high growth rates of the cost of milk were revealed. Measures are proposed to maintain the microclimate in the cowshed using HB LED lamps and the PM-Kit curtain system controlled by automated Farm Management Support systems. The system allows to control many basic processes for animal care, but the article only covers lighting and air exchange. The measures will increase the average annual productivity of animals by 7.3% and reduce the cost of 1 cent. of milk by 4.6%.

International audience; The reactor antineutrino anomaly might be explained by the oscillation of reactor antineutrinos toward a sterile neutrino of eV mass. In order to explore this hypothesis, the STEREO experiment measures the antineutrino energy spectrum in six different detector cells covering baselines between 9 and 11 m from the compact core of the ILL research reactor. In this Letter, results from 66 days of reactor turned on and 138 days of reactor turned off are reported. A novel method to extract the antineutrino rates has been developed based on the distribution of the pulse shape discrimination parameter. The test of a new oscillation toward a sterile neutrino is performed by comparing ratios of cells, independent of absolute normalization and of the prediction of the reactor spectrum. The results are found to be compatible with the null oscillation hypothesis and the best fit of the reactor antineutrino anomaly is excluded at 97.5% C.L.

The first divergence of the international Jules Horowitz Material Testing Reactor under construction at CEA Cadarache is foreseen in 2016. In order to perform all the design and safety studies, a specific neutron and photon calculation tool, HORUS3D/NP in this frame, the validation and qualification steps aim at quantifying all the biases and associated uncertainties of HORUS3D/N&P calculations. These biases originate from both the nuclear data and the calculation scheme, for calculations at step zero (JHR BOL core) or during depletion (JHR core at equilibrium). This paper focusses on the quantification of the biases due to nuclear data and the associated uncertainties. A new experimental program, named AMMON, was performed between 2010 and 2013 to provide experimental data for this quantification. A large part of the measurements has been today analyzed with the Monte Carlo TRIPOLI-4® code and the JEFF3.1.1 and EPDL97 data libraries relative to neutron/photon transport and photon emission. The C/E results were transposed from AMMON to JHR. The synthesis of the present analysis is very satisfactory. The calculation biases remains limited. In addition, thanks to a very good control to the experimental uncertainties during measurements, it is shown that the a priori uncertainties due to nuclear data for parameters at step zero was reduced up to a factor of 2.

The closing article of the series is concerned with the problems of the creation of nanostructures with more or less sophisticated architecture. If the nanoparticles themselves are mainly of academic inter-est, their assemblies can be used as the working elements of future devices. Such assemblies perform completely new and unexpected properties, which can not be treated as the simple sum of the their con-stituent particles. Nanoparticles can be organized into the assembly by various ways – by means of elec-trostatic, capillary, Van-der-Vaalce and other interactions. Of the special interest is the self-assembly, being known as an attribute of the living matter, but possible in the more primitive form in the inorganic systems, as it is demonstrated with the examples of chemical assemblage and template synthesis. The role of the biomolecules and effects of biospecific recognition in the nanostructures formation is discussed, as well as the possibilities to arrange nanoparticles in the desired order using the atomic-force microscopes. Key words: nanoparticles, nanostructures, self-assembly, colloidal crystals, layer –by-layer assembly, template synthesis, biomolecules.

The second article of the series deals with the main trends in the development of the methods to obtain nanoparticles – so called “bottom-up” and “up-bottom”. In the first case small particles are formed as a result of combination of the smaller ones (atoms as a limit), in the second – as a result of dispergation of the bulk matter. The electronic structure and the properties of the particles therewith could be different in the dependence on the way they were obtained (by means of dispergation or the atomic aggregation). Atoms and very small clusters can be stabilized by methods of cryochemistry discussed in the article. Nanoparticles formation by means of chemical and radiochemical synthesis, synthesis in the heterophase systems, providing the effective control of particle size and shape, the ways to obtain core-shell and hollow particles are considered next as well as the principles of the mechanical and chemical (redox) dispergation of the solids, leading to the ultradispersive and nanosized particles formation. Key words: nanoparticles, formation, chemical, cryochemical and radiochemical synthesis, dispergation.

The article (the first one from the suggested serial) deals with the main ideas, conceptions and terms of the new and rapidly developing sphere of human cognition and practice – nanotechnology. The nanochemistry problem field is determined and it’s objects (clusters, nanoparticles, quantum dots) are briefly characterized as well as their very special properties. Nanochemistry is a new area of modern science. In the field of education the training courses considering interdisciplinary character of given area of a science are now developed. Key words: chemical education, nanotechnology, nanochemistry, nanoparticles.

The group of patients with hereditary microthrombocyte thrombocytopaty has been studied. The diagnostic criteria for this form of thrombocyte pathology have been determined, the effective methods of the treatment have been shown.

With the aim of determination of the levels of children's health risk from chemical air pollution caused by vehicle emissions, on the territory of the municipal district of the city of Salekhard there was carried out the work on the study of the intensity and the chemical structure of traffic-related air pollution in the locations of 16 children's preschool institutions. There was used the technique of the counting campaign for the structure and intensity of road traffic flows, children's health detriment was calculated according to the method of risk assessment. The main danger in the emissions of vehicles is belonged to nitrogen dioxide (43.6%), benzo(a)pyrene (37.4%), carbon monoxide (6.57%), formaldehyde (4.43%). Being detected at the level of I0(-4)-10(-5) and corresponding to the maximum permissible risk estimated cancer risk is a subject for continuous monitoring.

Positive and negative phonotaxis (PPT and NPT) — two most important forms of insect acoustic behaviour — have been investigated with regard to their fundamental characteristics in mature animals. But little is known about ontogeny although it might be interesting from evolutionary point of view. Shuvalov & Popov (1971) showed that young females Acheta domesticus. sitting on the substrate before the hole entrance, demonstrated escape reaction to sounds of the whole perceptible range. By the time of sexual maturity the reaction to low frequency (LF) sounds (in the range of the main calling song frequency) disappears, while the reaction to high frequency (HF) sounds remains. The authors suggested, that disappearance of NPT to LF by the moment of sexual maturity may be connected with appearance of PPT to the calling song (CS).

By infrared spectrography and gas-liquid chromatography the composition of the slimy substance of the thermophilic culture Bac. subtilis-20 has been investigated. The slimy substance synthesized by Bac. subtilis-20 has been shown to be a polysaccharide. Xylose, amnnose and glucose have been found in its acid hydrolysate.