Navegando por Autor "Pereira, Sara Souza"

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    Construção de um sensor eletroquímico com nanotubos de carbono e niclosamida para determinação de ácido ascórbico
    (Instituto Federal de Educação Ciência e Tecnologia de Alagoas, 2021-03-10) Pereira, Sara Souza; Lopes, Cleylton Mitre Bezerra; http://lattes.cnpq.br/4037905253098595; Silva, Leonardo Vieira da; http://lattes.cnpq.br/0733464041429281; Santos, Nicholas Deymisson dos; http://lattes.cnpq.br/2401211277616613
    Nanotechnology is an extensive research area and has been one of the technologies of Latest and growing advanced manufacturing worldwide. She studies a variety of materials produced at the nanometer scale through different methods chemical and physical, changing the paradigms of biosensitivity due to the properties unique to nanomaterials. (RIVAS, 2017; ANZAR, 2020) The development of sensors electrochemicals is one of the largest and fastest growing areas within Analytical chemistry. These devices make use of an electrode as a device signal transducer and are based on charge transfer processes. In an attempt to improve the kinetic and analytical parameters, chemically (EQM), manufactured by modifying the surface of the electrode using various materials. Among them one of the ones that are used very frequently are carbon nanotubes, as they have excellent electrical properties, along with with niclosamide, which has a nitro group, used in redox systems. You nanomaterials have aroused the interest of the scientific community due to their unique physicochemical properties such as high reactivity, quantum effects, size small and large surface. Nanomaterials have dimensions below 100 nm, this group of materials allows access to several new magnetic, electronic, mechanical or optical. (ANZAR, 2020; XIANG, 2020 it was possible to obtain results promising through electrochemical techniques such as cyclic voltammetry and the chronoamperometry, electroanalytical studies were carried out and thus the efficiency of the reaction between immobilized materials and ascorbic acid, determining a catalytic constant of 2.1044 L mol -1s-1.
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    Produção de substrato a partir de resíduos de manga rosa para adsorção de misturas de semioquímicos
    (INSTITUTO FEDERAL DE ALAGOAS - Ifal, 2026-01-02) Pereira, Sara Souza; Aquino, Nathaly Costa de; https://orcid.org/0000-0002-2785-591X; http://lattes.cnpq.br/8050425431023649; Freitas, Johnnatan Duarte de; https://orcid.org/0000-0002-6977-3322; http://lattes.cnpq.br/4999402869058858; Freitas, Alan John Duarte de; https://orcid.org/0000-0001-9673-7338; http://lattes.cnpq.br/7222112856028905; Nascimento, Ruth Rufino do; https://orcid.org/0000-0002-2005-4941; http://lattes.cnpq.br/7975227032836139
    Fruit farming occupies a prominent position in the Brazilian economy, contributing significantly to the domestic market and exports; however, it is severely impacted by insect pests, especially Anastrepha obliqua, responsible for significant losses, mainly affecting fruit crops such as mango, cajá, and seriguela. The control of these pests has traditionally been based on the intensive use of chemical pesticides. In this context, the adoption of more sustainable strategies, such as Integrated Pest Management (IPM), demands the development of new technologies that reconcile efficiency in control and reduction of environmental impacts. This work aimed to develop and evaluate an adsorbent substrate based on pink mango peel waste, associated or not with chitosan, intended for the adsorption and controlled release of semiochemical mixtures formed by the combination of male sex pheromones and kairomones from pink mango. Mango peel powder in green and mature stages was used, as well as hybrid formulations containing 50% peel and 50% chitosan. The evaluated synthetic mixtures of semiochemicals (M1, M2, M3, and M4) were formulated from compounds previously identified through electroantennography (α-pinene, β-myrcene, camphene, sabinene, linalool, 1-heptanol, (Z)-3-nonen-1-ol, and α-farnesene). Physicochemical characterization was performed using Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), Thermogravimetric Analysis (TG), and Differential Scanning Calorimetry (DSC). SEM analyses revealed irregular surfaces and high roughness in the mango peel powders and chitosan. FTIR spectra indicated the presence of similar polar functional groups among the materials, mainly hydroxyls (-OH), carbonyls (C=O), and amines (-NH₂). TG results demonstrated similar mass loss profiles for green and ripe pink mango samples. DSC analysis allowed the identification of thermal events. The results indicated that the green pink mango peel powder, especially in the hybrid matrix with chitosan, is more efficient in highlighting the semiochemicals of the mixtures, particularly the M2 mixture.