COMPARISON OF TWO STAINING METHODS FOR ANODIZING IN ALLOY 6063 ALUMINUM PROFILES
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.
Read ArticleCOMPARATIVE STUDY OF ALCOHOLIC EXTRACTION OF COMPOUNDS FROM ARAUCARIA ANGUSTIFOLIA: MICROWAVE-ASSISTED EXTRACTION VS. MACERATION EXTRACTION
Background: The Araucaria angustifolia is a prominent tree species indigenous to the southern regions of Brazil. The tree can be a source of different compounds of interest if properly used. Aims: This research aims to compare the alcoholic extraction of compounds from Araucaria angustifolia using two different methods, microwave-assisted extraction and maceration extraction. Methods: Alcahoolic extractions of compounds from the sawdust of Araucaria angustifolia were performed using microwave-assisted extraction and maceration extraction. The color was observed by eye inspection. The taste was observed by putting the samples into the mouth and tasting it. The olfactive test was conducted at hot and cold temperatures. Results: it was obtained red color solution, both from the bark and from the branch. The intensity of the color changed with the extraction method and time of maceration. The solutions tasted like "green wood". Discussion: MAE and Maceration extraction can provide extracts from the bark and branch of the araucaria tree. There is the possibility that the “green wood” taste of the MAE extract can be changed with the thermal treatment of the wood. Conclusions: microwave-assisted extraction can perform the faster extraction of compounds from Araucaria angustifolia than maceration extraction.
Read ArticleCONTENT OF ANTIOXIDANTS IN SOME MEDICINAL PLANTS SOLD IN GEORGIAN PHARMACY CHAINS
Background: Antioxidant compounds are widely used in medicine to protect the organism from the impact of various stresses and strengthen the immune system. The primary source of natural antioxidants is considered plant-based products. That is precisely why scientists are interested in extracting active compounds out of plant materials and use them. However, diverse resources of medicinal plants of Georgia is poorly studied and used as a source of antioxidants. Aim: The research aimed to study the antioxidant composition and total antioxidant activity of some dried medicinal plants sold in the pharmacy network in Tbilisi, Georgia. Methods: Several types of medicinal plants (3 berry plants and 3 herbaceous plants) sold in the pharmacy chain were chosen as the research object. These are Crataegus sp., Sorbus sp., Viburnum sp., Helichrysum sp., Leonurus quinquelobatus Gilib, Origanum vulgare L. Results: As a result, it has been found that the content of ascorbic acid and carotene in the studied plants is not so high to fill the daily intake of a man with an infusion prepared from one tablespoon. As for proline and the number of total antioxidants, all the plants we have chosen are high in content, considerably increasing their medicinal value. Discussion: The low amount of ascorbic acid and carotine found in studied plant, this increases their medicinal value, and in combination with other antioxidants/plants, the healing effect of the raw materials has been used. Conclusions: The studied plants are characterized by high levels of proline and antioxidant activity, so their infusions can be safely used as a source of antioxidants both in folk medicine and for the preparation of biologically active preparations.
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