THE INFLUENCE OF CLIMATIC FACTORS ON THE CHANGE IN THE ELASTIC-STRENGTH INDICATORS OF EPOXY POLYMERS BINDERS USED IN LIQUID THERMAL INSULATION COATINGS
Introduction: Thermal insulating coatings are increasingly being introduced into construction practice for internal and external finishing enclosing structures and pipelines. Thermal insulation coatings are usually made based on polymer binder and mineral fillers. The durability and stability of the properties of heat-insulating materials depend on the type of binder. As a rule, polymers are used as a binder: epoxy resin; silicone rubber; urea-formaldehyde resins; aqueous dispersed polymers - styrene-butadiene, polyvinyl acetate, and acrylate (acrylic and styrene-acrylic). The quality indicator of binders can be assessed by the influence of the seasonality of climatic impact, and as a result, the best elastic strength characteristics of binders can be established after one month to a year of field tests. Aim: To determine the influence of climatic factors on the change in the elastic-strength indicators of epoxy polymers binders used in liquid thermal insulation coatings. Methods: A tensile testing machine of the AGS-X series with the TRAPEZIUM X software was used for mechanical tests. The tests were carried out in accordance with GOST 11262-2017 (ISO 527-2: 2012) "Plastics. Tensile test method". Results and Discussion: The paper discusses the results of experimental studies of the compositions of polymer binders and their resistance to various climatic factors, which will later be used as a polymer binder for thermal insulation coatings based on fine mineral granular systems. Conclusions: When analyzing the changes in the characteristics of polymer samples after exposure to climatic factors, it was found that compositions based on Etal-247 epoxy resin, cured with amine hardeners Etal-1440N, Etal-1460, Etal-1472, and Etal-45M, demonstrate the best elastic strength characteristics after one year of full-scale tests. The high stability of the indicators under consideration allows us to conclude that the use of Etal-247 resin as a base leads to creating of the most climate-resistant epoxy coatings.
Read ArticleENTREPRENEURSHIP, INNOVATION, AND COMPETENCY-BASED EDUCATION - INTERVIEW WITH PROF. PAULO CÂMARA. ENGLISH VERSION
Background: The interview was conducted with Professor Paulo Wilton da Luz Câmara, who serves as an associate professor at the University of Vassouras, general coordinator of postgraduate lato sensu programs, and deputy coordinator of the Master's in Environmental Sciences. The Professor has extensive academic and corporate experience. Objectives: The main objectives were to understand the importance of corporate experience in the role of a professor and researcher, discuss the evolution of public entrepreneurship policies in Brazil, understand the role of incubators, explore research on renewable energies in the defense sector, and learn about planned innovations for postgraduate programs. Methods: The interview was conducted in a semi-structured format with open-ended questions. The audio was transcribed for subsequent analysis and content structuring. Results: Corporate experience significantly influences academic performance. There has been relative improvement in public entrepreneurship policies, but the involved bodies lack specific knowledge. Incubators are necessary tools to foster entrepreneurship and innovation. The main challenges in renewable energy research for defense are awareness and organizational policy. Planned innovations for postgraduate programs include connecting education levels, shared management, and an open committee. Discussion: The Professor highlights the importance of practical corporate experience in enriching academic performance, noting advances in entrepreneurship policies while emphasizing the need for more specific knowledge. Incubators are seen as essential to fostering entrepreneurship and innovation. In the field of renewable energy applied to defense, challenges are related to awareness and organizational policy. Conclusion: The interview underscores the relevance of practical corporate experience in enriching academic performance and the need to improve entrepreneurship policies. Incubators are fundamental to fostering entrepreneurship and innovation. Research on renewable energies in defense faces challenges of awareness and organizational policy. Planned innovations for postgraduate programs aim for greater integration and participation.
Read ArticleSTUDY ON THE DPPH FREE RADICAL-SCAVENGING ACTIVITY OF SALVIA NEMOROSA L. AT TWO GROWTH STAGES
This study was designed to examine the DPPH free radical-scavenging activity, in different concentrations (0.025, 0.05, 0.07, 0.1, 0.2, 0.04 and 0.6) of methanolic extracts of Salvia nemorosa L. collected from the northwest of Iran (Zonouz and Ardabil regions) at two-stage of growth (vegetative stage leaves, flowering stage leaves, and flowers). The result showed that the mean of inhibition percentage in the Zonouz region increased in various concentrations and between flowers, vegetative stage leaves, and flowering stage leaves, compared with the plants of the Ardabil region. In each of the regions of Zonouz and Ardabil, the highest amount of DPPH inhibition was observed in the vegetative stage leaves in comparison with flowering stage leaves and flowers. In addition, in the effect of DPPH radical trapping in different concentrations of methanolic extracts of Salvia nemorosa L. was observed that from each of the collected region, methanolic extracts from sage plants were dose-dependent and acted very effective and useful and the best antioxidant activity was in the high concentration of extracts, So in Zonouz and Ardabil regions, the content of inhibition of DPPH increased significantly, by increasing the concentration of 0.025 mg/ml to 0.6 mg/ml and in Zonouz region the content of inhibition of DPPH similarly increased in 0.2, 0.4 and 0.6 mg/ml concentrations. In the Ardabil region, the most content of inhibition of DPPH was seen in 0.4 mg/ml and 0.6 mg/ml concentrations, but in this region, the content of inhibition of DPPH in 0.2 mg/ml concentration there was only in vegetative stage leaves and flowering stage leaves.
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