https://repositorio.ufu.br/handle/123456789/18812 2026-08-02T03:34:15Z 2026-08-02T03:34:15Z https://repositorio.ufu.br/handle/123456789/49067 2026-07-25T06:27:16Z 2026-03-05T00:00:00Z

Title: Cosméticos para esmaltação das unhas: uma revisão bibliográfica com ênfase em esmalte tradicional, acrílico e gel uv Abstract: Cosmetic products used for nail coating present complex formulations, composed of different classes of raw materials, selected to provide aesthetics, durability, and performance during application. Among the main products marketed, traditional nail polishes, acrylic systems, and UV-curable gels stand out, each differing in chemical composition, curing mechanism, and potential health risks. Conventional nail polishes are based on nitrocellulose, organic solvents, plasticizers, and pigments, remaining predominant in the market. In contrast, acrylic systems and UV gels use chemically or photo-activated (meth)acrylate monomers and oligomers, providing greater mechanical resistance to the coating. However, these formulations may trigger adverse effects, including allergic contact dermatitis, damage to the nail tissue, and photobiological risks associated with exposure to UV/LED lamps used for gel curing. Therefore, this literature review discusses chemical aspects, polymerization mechanisms, sanitary regulation, and potential toxicological implications, emphasizing the importance of safe application practices and professional qualification in handling these cosmetic products.

2026-03-05T00:00:00Z https://repositorio.ufu.br/handle/123456789/48969 2026-07-23T06:22:38Z 2026-03-19T00:00:00Z

Title: Avaliação da ozonização como processo oxidativo avançado na remoção de manganês em efluente de mineração: estudo de caso Abstract: The mining industry faces significant environmental challenges related to water management of effluents, especially due to the presence of dissolved metals that can persist even after conventional treatments, posing severe risks to ecosystems and public health. Among these contaminants, manganese stands out due to the difficulty of removal by chemical precipitation under near-neutral conditions, often proving insufficient to meet stringent discharge standards or generating large volumes of toxic waste. In this context, this work analyzes the application of ozonation, classified as an Advanced Oxidation Process (AOP), as a complementary technology in the treatment of mining effluents. The methodology was based on a critical literature review and the analysis of a pilot-scale case study, where ozonation was applied after conventional physicochemical treatment (High-Density Sludge (HDS) system) for the removal of manganese from copper mining effluents. The literature review and the analyzed case study demonstrate that ozonation can act synergistically with traditional physicochemical systems, such as the high-density sludge (HDS) process, functioning as a polishing step for the final adaptation of the effluent to environmental limits. Furthermore, the lower dependence on chemical reagents and the possibility of operation at near-neutral pH represent significant operational advantages. However, the viability of application on an industrial scale depends on factors such as electricity costs, gas-liquid transfer efficiency, and specific effluent characteristics, indicating that the technology's performance is strongly dependent on the operational context. Thus, although ozonation does not entirely replace conventional treatments, it is consolidating itself as a strategic alternative to increase the overall efficiency of the treatment system, reduce environmental impacts, and contribute to water sustainability in mining. As an academic contribution, this work integrates the fundamentals of oxidative chemistry with the environmental problem of metal removal in mining effluents, highlighting the relationship between reaction mechanisms, operational performance, and legal requirements, offering a theoretical basis for future experimental investigations and real-scale applications.

2026-03-19T00:00:00Z https://repositorio.ufu.br/handle/123456789/48889 2026-07-18T06:18:14Z 2025-12-03T00:00:00Z

Title: Síntese e avaliação da atividade antileishmania de derivados piridínico-imidazolínicos Abstract: Neglected Tropical Diseases (NTDs) remain a major global public health challenge, particularly leishmaniasis, whose high incidence and toxicity of current therapies demand new therapeutic alternatives. In this study, nine hybrid compounds were designed, synthesized, and evaluated through aromatic nucleophilic substitution (SNAr) reactions between pyridinic nuclei and sulfur-containing heterocycles (benzimidazole, benzoxazole, and benzothiazole). Molecular hybridization and bioisosterism strategies were applied to obtain derivatives with enhanced antiparasitic potential and improved pharmacokinetic profiles. The compounds were characterized by NMR spectroscopy (1H and 13C) and assessed for leishmanicidal activity against intracellular amastigotes of Leishmania infantum and cytotoxicity on human macrophages (THP-1). Compound 5 exhibited the best biological performance (IC₅₀ = 1.17 μM; Selectivity Index > 50), indicating high potency and low toxicity. In silico SwissADME analysis confirmed favorable lipophilicity and oral bioavailability. Overall, the molecular hybridization between pyridinic and sulfur heterocyclic cores proved to be a promising strategy for the development of new antileishmanial agents

2025-12-03T00:00:00Z https://repositorio.ufu.br/handle/123456789/48831 2026-07-15T06:26:04Z 2026-03-11T00:00:00Z

Title: Bioplásticos e compósitos à base de amido para embalagens alimentícias de uso único: propriedades, limitações e desafios ambientais Abstract: The widespread use of plastics in everyday life, combined with a culture of disposability, has resulted in the generation of large volumes of waste over short periods of time. The food packaging sector accounts for approximately 40% of global plastic consumption, with single-use packaging predominating. Due to contamination resulting from direct contact with food, these materials present limitations for reuse and recycling and are therefore predominantly disposed of in landfills or released into the environment, causing significant impacts on terrestrial and aquatic ecosystems. Consequently, only about 5% of these packages are effectively recycled and reintegrated into the production of new materials. In this context, replacing conventional petroleum-derived plastics with biodegradable packaging emerges as a promising strategy to mitigate such environmental impacts. Starch has attracted particular interest due to its abundance and renewability and can exhibit thermoplastic behavior when processed in the presence of plasticizers, moisture, and heat, which enables its shaping through conventional polymer processing techniques. This narrative review aimed to synthesize recent advances in the production of starch-based bioplastics and composites through a bibliographic search conducted in databases such as Google Scholar, ScienceDirect, and PubMed. Articles published between 2008 and February 2026 were considered in order to compile and discuss the main physicochemical properties of these materials, as well as their limitations. In general, starch-based bioplastics and composites enable the development of more sustainable materials with a lower carbon footprint compared to fossil-based plastics. These materials also stand out due to their low cost and high biodegradability relative to other biopolymers, as well as their potential integration into circular economy models through composting or biogas production. However, limitations related to mechanical properties and high sensitivity to water still restrict their application, although these drawbacks can be partially overcome through strategies such as the incorporation of additives and the formation of blends with other biodegradable polymers. In summary, the analyzed studies indicate that starch-based materials constitute a promising alternative to conventional plastics in disposable food packaging applications.

2026-03-11T00:00:00Z