COMPARISON OF THE EFFECT OF SILICON AND SILICON NANO-CHELATE IN REDUCING THE IMPACT OF SALINITY STRESS ON WHEAT SEEDLINGS
Today, salinity stress causes extensive damage to crops, and high soil salinity is one of the limiting factors for crop yields. A practical approach to lessen the negative effect of salinity stress is to use mineral nutrition methods such as spraying plants with silicone. To investigate and compare the effect of silicon and silicon nano-chelate on the wheat plant resistance (Shiroodi cultivar) to salinity stress, a factorial experiment was designed and conducted in a completely randomized design with five replications under hydroponic conditions. Experimental treatments included concentrations of 0 and 2 mmol/L silicon, 0 and 0.424 g/L silicon nano-chelate, 0 and 150 mmol/L sodium chloride, and their interaction. The growth and physiological indices showed that salinity stress decreasing effect on shoot dry weight, root fresh weight, catalase activity, and ascorbate peroxidase. These increases indicate the activation of the plant defense system against salinity stress conditions. The results also showed that silicon nano-chelate treatment under salinity stress reduced dry and fresh weights of roots and shoots. These two compounds additionally influenced the content of catalase activity, ascorbate peroxidase, and superoxide dismutase content in shoots. Simultaneously, the silicon and silicon nano-chelate treatment under salinity stress reduced the dry and fresh weight of roots and shoots, catalase activity, and ascorbate peroxidase. Therefore, the results obtained in this study generally showed that silicon under salinity stress increased plant growth and positively affected the activity of its antioxidant system. But silicon nano-chelate not only did not improve plant performance but also reduced its growth.
Read ArticleSUSTAINABILITY, INNOVATION, AND INTEGRATION: PROFESSOR RIBAMAR'S VISION FOR BRAZIL'S CHEMISTRY PROFESSION
Background: The interview with Professor José de Ribamar, conducted by Luís de Boni, addresses various aspects of his career and contributions to chemistry in Brazil. The conversation includes his experiences in teaching, research, and university administration, as well as his role as President of the Federal Council of Chemistry (CFQ). Aims: The primary aim of the interview is to highlight Professor Ribamar's achievements and challenges throughout his career, and to explore his views on chemistry and its impact on scientific and educational development in Brazil. Methods: The interview was conducted in a question-and-answer format, allowing Professor Ribamar to share his experiences and insights in a detailed and personal manner. The interview was recorded, transcribed, and is available in both text and video formats. Results: Professor Ribamar detailed his academic and professional journey, including his undergraduate and graduate studies in chemistry, his contributions as a professor at the Federal University of Maranhão (UFMA), and his initiatives as a course coordinator and department head. He also discussed the impact of his research and his vision for the future of chemistry, emphasizing the importance of artificial intelligence and algorithms in predicting chemical models. Discussion: The interview provided a comprehensive overview of Professor Ribamar's contributions to chemistry in Brazil. He emphasized the importance of education and ongoing research for scientific advancement, as well as the need to adapt to new technologies. The discussion also addressed the challenges the scientific community faces and the importance of interdisciplinary collaboration. Conclusion: Professor José Ribamar has significantly promoted and developed chemistry in Brazil in academia and public administration. His career illustrates the importance of dedication to education and research, and his reflections offer valuable lessons for future generations of scientists and educators. The interview serves as a testament to his lasting impact on the scientific community.
Read ArticleCLINICAL AND LABORATORY TESTING OF A NEW MODIFICATION OF TWO-LAYER "SILEP" DENTURES USED IN PROSTHETIC DENTISTRY
Dentistry is a part of medicine, where various polymer materials were used for the first time. Many factors forced researchers to find more stable, versatile, and hygienic materials for the manufacture of dental products. It is important to note that the search for the ideal polymer dental material is still ongoing. This is because modern polymers, in some cases, do not meet the specified requirements for chemical, physical, strength, and elasticproperties. Based on the data on the method of creating and using silicone material for the base of the removable prosthesis "Gossil", an improved silicone material for two-layer dentures "Silep" was developed, as well as a special primer for better connection of the lining with the rigid acrylic base of the prosthesis. To evaluate the most suitable compound, materials were tested for several parameters, such as tensile strength, elongation, and shore hardness. In addition to selecting a suitable material for modification, the selection and testing of an adhesive that allows the chemical bonding of the acrylate surface to the siloxane surface were carried out.
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