Use of compound feed with the probiotic feed supplement based on Bacillus bacteria for sterlet producers

The effect of feed with probiotics B-1895 and Subtilis-C on the growth and physiological condition of sterlet producers in the RCD was studied. It was found that the weight gain in the first experimental group was higher by 13.3 % and in the second group by 53.3 % in comparison with the control. A positive effect of the probiotics studied on the stabilization of the physiological state of the fish that experienced little stress at the beginning of the experiment has been revealed. As a result, the normalization of physiological and biochemical parameters with a decrease in blood levels of haemoglobin, cholesterol, triglycerides and beta-lipoproteids is noted. No significant effect of the probiotics studied on the generative function was found. Besides a positive effect of the probiotic «Subtilis-C» on the prevention of oocyte resorption was shown

FE Simulation of the Stress-Strain State during Shear-Compression Testing and Asymmetric Three-Roll Rolling Process

A three-roll rolling process is a significant technique in the production of wire rod, round bars and hexagonal profiles for structural applications. Better mechanical properties of wire rod, round bars and hexagonal profiles can be achieved due to large plastic deformation by the three-roll rolling process. Asymmetric rolling is a novel technique characterized by a kinematic asymmetry linked to the difference in peripheral speed of the rolls, able to introduce additional shear strains through the bar thickness. Physical simulation of shear strain, which is similar to that occurring in asymmetric three-roll rolling process, is very important for design of technology of producing ultrafine grain materials. Shear testing is complicated by the fact that a state of large shear is not easily achievable in most specimen geometries. Application of the shear-compression testing and specimen geometry to physical simulation of asymmetric three-roll rolling process is discussed in the paper. FEM simulation and comparison of the stress-strain state during shear-compression testing and asymmetric three-roll rolling process is presented. The results of investigation can be used to optimize the physical simulation of asymmetric three-roll rolling processes and for design of technology of producing ultrafine grain materials by severe plastic deformation

FE Simulation of the Stress-Strain State during Shear-Compression Testing and Asymmetric Three-Roll Rolling Process

A three-roll rolling process is a significant technique in the production of wire rod, round bars and hexagonal profiles for structural applications. Better mechanical properties of wire rod, round bars and hexagonal profiles can be achieved due to large plastic deformation by the three-roll rolling process. Asymmetric rolling is a novel technique characterized by a kinematic asymmetry linked to the difference in peripheral speed of the rolls, able to introduce additional shear strains through the bar thickness. Physical simulation of shear strain, which is similar to that occurring in asymmetric three-roll rolling process, is very important for design of technology of producing ultrafine grain materials. Shear testing is complicated by the fact that a state of large shear is not easily achievable in most specimen geometries. Application of the shear-compression testing and specimen geometry to physical simulation of asymmetric three-roll rolling process is discussed in the paper. FEM simulation and comparison of the stress-strain state during shear-compression testing and asymmetric three-roll rolling process is presented. The results of investigation can be used to optimize the physical simulation of asymmetric three-roll rolling processes and for design of technology of producing ultrafine grain materials by severe plastic deformation

Current state of the Sea of Azov main commercial fishery resources and ways to restore them

The paper presents the result of analyses of the Azov Sea fishery resources state for the last 15 years of the last century up to the present time. The information on quantitative and qualitative composition of commercial catches is obtained from the data of fishery statistics. Changes in temperature and salinity and their anomalies relative to mean annual values are highlighted. The first four commercial species with maximum catches have been identified: anchovy, kilka, gobies and Redlip mullet. The dynamics of their ratio, at different periods of the current century, may indicate the influence of external conditions (temperature, salinity, etc.). The forecast on increase of catches of the listed species and recommendation on development of the Azov sea fishery development programme, including all directions of fishery, introduction of the newest achievements of science and technology in development of aquaculture and other branches connected with rational use of aquatic biological resources of the sea are given

Use of compound feed with the probiotic feed supplement based on Bacillus bacteria for sterlet producers

The effect of feed with probiotics B-1895 and Subtilis-C on the growth and physiological condition of sterlet producers in the RCD was studied. It was found that the weight gain in the first experimental group was higher by 13.3 % and in the second group by 53.3 % in comparison with the control. A positive effect of the probiotics studied on the stabilization of the physiological state of the fish that experienced little stress at the beginning of the experiment has been revealed. As a result, the normalization of physiological and biochemical parameters with a decrease in blood levels of haemoglobin, cholesterol, triglycerides and beta-lipoproteids is noted. No significant effect of the probiotics studied on the generative function was found. Besides a positive effect of the probiotic «Subtilis-C» on the prevention of oocyte resorption was shown