6,966 research outputs found
DEVELOPMENT OF A MODEL FOR THE PRODUCTION OF METAL-POWDER COMPOSITIONS BASED ON CO-CR ALLOYS BY ELECTROEROSIVE DISPERSION
Abstract. The main requirement for powders for additive 3d technologies is the spherical shape of theparticles. Such particles are most compactly packed into a certain volume and ensure the "fluidity" of the powder composition in the supply systems of the material with minimal resistance. The wide use of the EED method for processing metal waste into powders for the purpose of their reuse and application in additive technologies is hampered by the lack in the scientific and technical literature of full-fledged information on the effect of the initial composition, regimes and media on the properties of powders and technologies of practical application. Therefore, in order to develop technologies for the reuse of electroerosive powders and to evaluate the effectiveness of their use, complex theoretical and experimental studies are required. The aim of the work was to develop a model for the production of metal powder compositions on the basis of Co-Cr alloys by electroerosive dispersion. Based on the results of the conducted studies, it has been established that the optimum parameters for the process of obtaining powder materials by the method of electroerosive dispersion of butyl alcohol are: capacitance of discharge capacitors 48 μF, voltage on electrodes 100 V, repetition rate of pulses 120 Hz
Analysis of agriculture sustainable development in Russia
The article is focused on determining the current situation in Russia on the way to achieving the goals of sustainable development in agriculture. When analyzing the literature, it was revealed that most of the goals and objectives of sustainable development are already, to a greater or lesser degree, incorporated into the main strategic and program documents in Russia. Achievements in the implementation of SDG 2 “End hunger, achieve food security and improved nutrition and promote sustainable agriculture” were considered. Statistical indicators of agriculture sustainable development in Russia are analyzed. The principles for development of the agrifood systems sustainability concept are formulated and presented. In the last century and a half, the main task of Russia in country’s food security has been to feed its population. At the present day, it can be stated that this problem has been mainly solved
Characteristics of the Spatial Development of Innovations in Legislative Acts of Siberian Macroregions
Objective: to assess the level of inclusion of the innovation space characteristics into the legislative acts on innovation activity in the macroregions of Siberia.Methods: a spatial approach, which allowed considering the innovative development of a macroregion through the characteristics of length, connectivity, density, and uniformity; a synchronous method, which made it possible to compare legislative documents in the macroregions of Siberia by the representation of spatial characteristics in them; a qualitative content analysis, used to identify words and phrases characterizing the spatial development of innovations in the texts of legislative documents on innovation activity.Results: the paper revealed the increased attention of foreign and Russian scientists to the search for ways of improving the effectiveness of legislative regulation of innovation activity. It was determined that the regional legislative acts of the macroregions of Siberia (Ural-Siberian and South-Siberian macroregions) regulating innovation policy do not actually reflect the characteristics of the innovation space (such characteristics as interaction, cooperation, communication, and partnership are highlighted). In less than half of the analyzed documents, there are no characteristics of spatial development of innovations, in a third – interterritorial cooperation is mentioned as a characteristic of spatial development. In the studied documents, the predominant form of cooperation and interaction is the formation of clusters and the coordinated development of science, innovation, production, and education.Scientific novelty: for the first time, the article evaluates the representation of spatial characteristics of innovation development in the relevant legislative acts of the macroregions of Russia. It is shown that the territories of macroregions should have denser, more intensive links in the development of innovations in order to meet their intended purpose. The author suggests improving the legislative regulation of innovation activity by including the requirement for regions to develop intersectoral and interterritorial interaction.Practical significance: the analysis of legislative acts presented in the article in the field of innovation support and innovation development from the viewpoint of the spatial approach can be useful for correcting the existing and developing the new approaches to spatial and innovative development of macroregions of Russia. The research results are intended for public authorities involved in the formation of the innovation policy of the regions
Evaluating the efficiency of the research sector in Russian regions: a dynamic data envelopment analysis
The nonparametric method of dynamic data envelopment analysis (DDEA) has become increasingly popular for conducting comparative efficiency evaluations. In recent years, dynamic data envelopment analysis (DDEA), a variant of this method, has gained significant attention. This article applies dynamic analysis to evaluate the efficiency of the research sector in Russian regions. Traditional input variables such as the number of research staff and R&D expenditure are considered, while publication and patent metrics serve as output indicators. The analysis covers a substantial time period, spanning from 2009 to 2020. Notably, the proposed evaluation method incorporates publication quality measures as a carry-over variable, in addition to accumulated R&D expenditure. The study employs dynamic data envelopment analysis to compare the obtained results with previous evaluations of the research and technology sector in Russian regions. The findings demonstrate that the proposed method serves as a valuable ranking technique, enhancing existing evaluations of regions' research and technology potential in terms of efficiency. The article concludes by discussing the prospects and limitations of the method in evaluating and forecasting research and technology profiles of regions
Magnetism of coupled spin tetrahedra in ilinskite-type KCuO(SeO)Cl
Synthesis, thermodynamic properties, and microscopic magnetic model of
ilinskite-type KCuO(SeO)Cl built by corner-sharing Cu
tetrahedra are reported, and relevant magnetostructural correlations are
discussed. Quasi-one-dimensional magnetic behavior with the short-range order
around 50\,K and the absence of long-range order down to at least 2\,K is
observed experimentally and explained in terms of weakly coupled spin ladders
(tubes) with a complex topology formed upon fragmentation of the tetrahedral
network. This fragmentation is rooted in the non-trivial effect of the SeO
groups that render the Cu--O--Cu superexchange strongly ferromagnetic.Comment: 9 pages, 7 figure
Constructions of regular algebras
Criterion of (Shilov) regularity for weighted algebras on a
locally compact abelian group is known by works of Beurling (1949) and
Domar (1956). In the present paper this criterion is extended to translation
invariant weighted algebras with . Regular algebras
are constructed on any sigma-compact abelian group . It was proved earlier
by the author that sigma-compactness is necessary (in the abelian case) for the
existence of weighted algebras with .Comment: Submitted to Mat. Sborni
Properties of filled compositions based on emulsion pvc
Set influence of chalk on the technological and technical properties of plastisol and compounds of PVC emulsion used in the manufacture of children's toys. Studied rheology filled with chalk plastisol and compounds. We studied the stability filled with chalk plastisols. Given the elastic-strength properties filled with plasticized PVC
- …