SOUTHERN JOURNAL OF SCIENCES

Background: Aluminum stands out for being a light, corrosion-resistant, and recyclable metal, achieving wide coverage in the market. When incorporated into alloying elements, it is possible to acquire other desirable characteristics. Alloy 6063, intended for architectural purposes, has aesthetic, structural, and strength functions. Anodized finishing is performed through an electrolytic process, ensuring a more resistant aluminum oxide film than that formed naturally. For decorative purposes, the anodic film coloration can be performed by several methodologies, in this case, for the coloration by organic adsorption, with the use of aniline, and the electrolytic coloration, composed of tin sulfate salts, both for obtaining the black color. Aim: Compare of two different staining methods on the surface of anodized profiles of aluminum alloy 6063. Methods: Profile samples were collected and tests were carried out to measure the thickness of the anodic layer, immersion tests with 3,5 percent sodium chloride, for 1000 hours, and neutral saline mist, for 600 hours. Results and Discussion: Both methodologies proved to be resistant to immersion tests with sodium chloride, as well as with neutral saline mist, and these tests are quite aggressive and provide corrosion of the material when not well treated. Corrosion points were only seen at the intersections performed, and in the rest of thearea, no points were detected. Conclusions: The result of both methodologies was positive, considering tht there was no corrosion in the tested samples, except in the intersections performed, as well as the maintenance of the color in both tested methodologies, which was not expected in the literature. For future work, it is suggested to deepen the study to perform electrochemical impedance spectroscopy tests for exaluate the strength of the anodic film and perform anodizing with the same parameters, however, with different anilines to analyze their behavior.

During the construction of concrete structures of small cross-sections, the release of heat during cementhardening has no harmful effects. With the increasing temperature of the hardening cement mass, the rate ofcement hydration increases. This increases the rate of release of its heat of hydration of cement. Theconsequence of the accelerated process of hydration of the binder is a more intensive increase in the strengthof cement stone than in the case of hardening under normal conditions. This fact is widely used in practice forthe intensification of the hardening of concrete. When structures with small cross-sections are being built, theheat released during hardening is relatively quickly transferred to the surrounding space and does not cause asignificant increase in temperature. In structures made of massive concrete (with a large cross-section), thisheat is stored in the interior of the array for a long time, which causes a rather large rise in temperature and itsslow drop. This is due to the fact that heat transfer to the external environment is hampered here by theconsiderable thickness of the massif and the rapid rate of concreting, mechanized laying of large masses ofconcrete. As a result, a temperature difference is created between the internal and external parts of thestructure and harmful internal stresses arise that can cause cracking in the hardened concrete. This leads to aviolation of its solidity. The faster cement hydrates, the sooner and more heat is released. The types of cementswith a high content of tricalcium silicate and aluminate emit more heat and rather than types of cement with ahigh content of dicalcium silicate and tetra-calcium aluminoferrite. However, the latter has a lower strength. Theincrease in strength resulting from the hydration process is inevitably associated with the release of heat into theenvironment. C

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.