INVESTIGATING THE EFFECT OF COLD TEMPERATURE STRESS ON UNOPENED MALE CATKINS AND INOCULATED FEMALE FLOWERS OF IRANIAN NATIVE HAZELNUT CULTIVARS
In many low-temperature areas, the environmental factor is an important limiting factor for the production and distribution of horticultural plants. This study aimed to investigate the cold tolerance of the male catkins and inoculated female flowers to screen the popular native hazelnut cultivars in Qazvin under low-temperature stress. A completely randomized factorial block design with three replications was used in this experiment with eight cultivars (Nakhnroud, Khandan, Mish-Pestan, South of Qarabagh, Asl-e-Qarabagh, Rasmi, and Gerdashkevar). After removing each of the treated samples at the end of the experiment, the samples were examined morphologically (appearance) and compared with the control. The changes were recorded as qualitative traits. To understand the influence of cold stress on reproductive organs, hydrogen peroxide and proline were measured. The results showed the onset of freezing in unopened male catkins at -7 and -9 °C and in inoculated female flowers at -3 °C. Damage to unopened male catkins' tissue occurred at -11 °C and in female flowers at -5 °C. The highest value observed among cultivars in the case for proline content of male catkins was in Mish-Pestan and Khandan cultivars with 0.816 and 0.660 µmol/ g FW, respectively. In inoculated female flowers, Mish-Pestan and Tabestaneh cultivars with 0.185 and 0.168 µmol/ g FW, respectively, showed the highest statistically significantincrease in proline content. Interestingly, the cultivars with the highest proline content in male catkins indicated the most increase in H2O2; Mish-Pestan and Khnadan with 0.569 and 0.541 ug/g FW, respectively. Asl-eQarabagh was observed to have the least H2O2 content (0.042 ug/g FW) among cultivars. Again, in inoculated female flowers, those with the highest concentration of proline (Mish-Pestan and Tabestaneh) were found to have the highest H2O2 content (0.335 and 0.331 ug/g FW, respectively
Read ArticleTHE 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 ArticleCALCULATION FOR REDEMPTION OF COMPACT TESTING BY THE PROCTOR METHOD THROUGH NEWTON’S GRAVITATIONAL POTENTIAL ENERGY
Throughout this article, a study on the characteristics of the compaction test by the Proctor Method, regulated by ABNT NBR-7182, which is used to verify the degree of soil compaction, will be approached in order to broaden the discussion and raise points that demonstrate the urgent need to make it more accurate, efficient and safe. Through qualitative and quantitative research carried out by the authors of this article, it sought to collect data through a questionnaire for professionals in the field of geotechnics in the “Quadrilátero Ferrífero” region in Minas Gerais. In addition to other relevant data for the topic, it was raised that of the 22 professionals from the participating region, 72.7% of the total belief that the manual compaction test can be manipulated by an operator during the test execution, failing to generate results reliable, thus showing the importance of the proposed theme. In this way, we initially sought to correlate the Compaction Energy formula idealized by Ralph Proctor with Isaac Newton’s Gravitational Potential Energy formula and, through it, present the resizing, which may enable the construction of manual, semi-automatic human propulsion machines (not or making the automated ones that depend on electricity available to the market. In conclusion, from the mathematical calculations, it was possible to evidence the use of Newton’s Gravitational Potential Energy to constructnew equipment to carry out this test.
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