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Preliminary results of measurements of the total reaction cross sections σR for nuclei4He,6He,8He,7Li,8Li,9Li,11Li,7Be,9Be,10Be,11Be,12Be,8B,10B,11B and12B nuclei at energy range (10-50) AMeV with28Si target is presented. The secondary beams of light nuclei were produced by bombardment of the 15N (50 AMeV) primary beam on Be target and separated by COMBAS fragment- separator. In dispersive focal plane a horizontal slit defined the momentum acceptance as 1% and a wedge degrader of 600 µm Al was installed. The Bρ of the second section of the fragment-separator was adjusted for measurements in energy range (10-45) AMeV. The strong absorption model reproduces the A-dependence of σR , but not the detailed structure. We are comparing our experimental data with predictions of microscopic (dashed line) and strong absorption model, Glauber multiple scattering theory and preliminary results are obtained.

Secondary beams (6Li,7Be,8B) were obtained by the separation of fragmentation products of a15N ion beam (50 MeV/A) impinging on a Be target using the COMBAS spectrometer. The secondary products were detected by a telescope consisting of five Si-detectors (dE) and a stop CsI(Tl) detector. The telescope allowed us to achieve unambiguous particle identification of fragments originating from incident secondary beams as well as their reaction products resulting from interaction with the Sidetectors, chosen as a secondary target. This way, break-up reactions of6Li,7Be and8B have been studied in this experiment, in particular the longitudinal momentum distributions of7Be fragments in the break-up of8B on a Si have been measured at 30 MeV/A.

Neutron-removal cross-section ( σ-xn ) measurements of neutron-rich light nuclei were performed on the COMBAS fragment-separator with a multi-detector Si telescope at intermediate energies (22-34) MeV/nucleon. The removals of one neutron from8Li and9Be, two neutrons from6 He and10 Be and four neutrons from 8 He were observed from the reactions on a Si-CsI(Tl) telescope. Results of σ-xn for6 He,8 He,8 Li,9 Be and10 Be nuclei were obtained and compared with those of previously measured data. The data indicate that4 He is a good core within6 He and8 He. Furthermore, we found that9,10 Be nuclei disintegrated by one- and two- neutron removal reaction, respectively.

The study was performed on alloys with a carbon content of 0,37-0,57 % (wt.), silicon 0,23-0,29 % (wt.), manganese 0,7-0,86 % (wt.), the rest– iron. To determine the phase composition of alloys used microstructural, microanalysis and X-ray analysis. In addition, the physical characteristics of the alloys studied in this paper were determined, such as alloy chemical dependence of extension and contraction ratio, impact toughness and hardness. The results obtained in this paper showed that the iron-based alloy with the content of carbon of 0.57 % (wt.), silicon of 0.28 % (wt.) and manganese of 0.86 % (wt.)) had the superior microstructure and physical properties. It was determined that after a number of crystallization and phase transformation the alloy phase structure includes two phases: a-iron and cement magnesium doping Fe2.7Mn0,3C.. For the first time using the method quasichemistry received an expression of the free energy of a γ-iron alloyed with silicon and magnesium, and determined the solubility limit of carbon, manganese and silicon. The maximum content in γ-iron can reach: carbon 6,8 % (at.), manganese – 67,5 % (at.), silicon – 2,3 % (at.).

The studies were performed for the specimens of Fe-B-C alloys with boron content of 0.005–7.0 wt.% and carbon content of 0.4–5.5 wt.%, the rest was iron. From the data of microstructure analysis, X-ray structural and differential thermal analyses, we determined the primary phases formed as a result of crystallization of Fe-B-C system alloys, depending on content of boron and carbon in the alloy. As a result of the experiment carried out in this work, the phase composition and phase transformations occurring in the alloys are investigated and the liquidus surface is constructed; it is shown that the point with minimum temperature of 1375 K at the liquidus surface is observed at boron content of 2.9 wt.% and carbon content of 1.3 wt. %. For the first time, considering the contribution of the first degree approximation of high-temperature expansion of thermodynamic potential into the Gibbs energy of Fe-B-C melt, we obtain the surface of thermodynamic stability of Fe-B-C melt, depending on temperature and content of boron and carbon in the alloy. The findings show that in order to obtain the homogeneous Fe-B-C melt, which does not contain micro-inhomogeneous structures in the form of short-range microregions, it is necessary to perform overheating more than to 150 K.

The experimental set-up based on the time-of-flight fragment-separator COMBAS and multi-channel registration system is developed for the studies of exotic light nuclei. Precise correlation method will be used for resonance decay spectroscopy.

A mechanisms of production of forward-emitted fragments in the 22Ne (40 АMeV) + 9Be reaction are investigated. Inclusive velocity and isotopic distributions of products with 3 ≤ Z ≤ 11 were measured on the fragment separator COMBAS. The contribution of direct processes and dissipative ones is presented. Gaussian fitting functions according to Goldhaber formalism has been used to estimate direct components of fragments velocity distributions. Experimental data have been compared to geometric incomplete fusion model predictions. Incomplete fusion model was the first time applied for light nuclei as in the studied reaction system. Overall agreement of simulations with experiment in description of velocity distributions have been achieved for fragments with atomic number close to the projectile mass and for stable isotopes. Discrepancies for other products are the result of transition from incomplete fusion to direct processes with collisions of clusters in the participant zone.

Results of mycotoxicological survey of representative samples of feed and procured wheat, barley, oat and maize grain batches are demonstrated. The samples were submitted by the Veterinary Service officials, livestock farmers and feed mill operators, agricultural producers, specialized commercial business operators and farm owners in seven Federal Districts of the Russian Federation in 2009-2019. Similar amounts of wheat and barley grain samples were received from the Central, Volga, Ural and Siberian Federal Districts. The amount of wheat samples delivered from the Southern Federal District prevailed over the number of barley samples, and the maize samples were mostly delivered from the regions of the Central Federal District. Fusarium toxins including T-2 toxin, diacetoxyscirpenol, deoxynivalenol, zearalenone and fumonisins of group B as well as alternariol, ochratoxin A, citrinin, aflatoxin В1, sterigmatocystin, cyclopiazonic acid, mycophenolic acid, ergot alkaloids and emodin were detected and measured according to the validated competitive ELISA procedure. Generalization of the results demonstrated domination of fusarium toxins and active involvement of alternariol in the contamination of all types of feed grains as well as high occurrence of emodin in ear cereals and increased occurrence of T-2 toxin and ochratoxin A in barley. Shift of medians and 90%-percentile of the basic contaminants to lower values as compared to mean and maximal ones was reported thus being indicative of their possible accumulation at the levels outside the typical range. The highest levels of T-2 toxin, deoxynivalenol and ochratoxin A as well as 90%-percentile values exceeded the acceptable levels. The maize grains demonstrated the whole complex of the tested fusarium toxins with the prevalence of T-2 toxin, deoxynivalenol, zearalenone and fumonisins; and the maximal amounts of these mycotoxins by several times exceeded the accepted regulatory levels. Diacetoxyscirpenol, aflatoxin В1, sterigmatocystin, cyclopiazonic acid and ergot alkaloids are classified as rare feed grain contaminants. High prevalence of alternariol and emodin known as “diarrhea factor” as well as maize grain contamination with mycophenolic acid (mycotoxin having an immunosuppressive effect) are for the first time reported in this paper. These data support the need of their introduction in the group of regulated substances significant for public health. Original monitoring data systematized and summarized in the paper are given in electronic format in section Additional materials.Part 1: Veterinary Science Today. 2020; 1 (32): 60–65. DOI: 10.29326/2304-196X-2020-1-32-60-65.

Results of the ten-year annual mycotoxicological testing of complete mixed feeds for pigs and poultry submitted by holdings and processing establishments located in the Northwestern, Central, Southern, Volga and Ural Federal Districts are presented. Competitive ELISA tests showed that the occurrence of T-2 toxin, deoxynivalenol, zearalenon, fumonisines B, alternariol, ochratoxin A, citrinin, mycophenolic acid, ergoalkoloids and emodin was about 5% and quantities thereof varied within one or three orders; quantities of T-2 toxin, deoxynivalenol, zearalenon, fumonisines, and ochratoxin A might exceed maximum admissible levels for feed grains. Diacetoxyscirpenol, aflatoxin В1, sterigmatocystin and cyclopiazonic acid belonged to group of rare contaminants. Level of feed contamination with T-2 toxin and emodin was found to be consistently high during the said period; in some of the years occurrence of deoxynivalenol, fumonisines as well as ochra­toxin A, citrinin, mycophenolic acid and ergoalkoloids increased. In 2016–2018, mixed feed contamination with alternariol increased whereas contamination with fumonizin steadily decreased and level of zearalenon occurrence remained consistently low. Evidence for a wide occurrence of emodin known as “diarrheic factor” as well as for sporadic increase in mixed feed contamination with alternariol, citrinin, mycophenolic acid, mycotoxins having the highly dangerous toxic impact and long-term adverse effects, was detected for the first time. These data confirmed the need for their inclusion into the regulated group of substances significant for public health. General features of pig and poultry feed contamination as well as usefulness of regional surveys for intoxication risk prediction are described. Special attention is paid to the importance of the projects for creation of common information resources that could become a unique scientific basis for innovations in feed poisoning prevention. Original monitoring data systematized and summarized in the paper are given in electronic format in section Additional materials.