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Caracterização e aplicação da lignina da palha de milho como coagulante e auxiliar de coagulação orgânico na remoção da turbidez de água
(Universidade Federal de São Carlos, 2026-06-16) Diniz, Joice Pereira; Gonzalez, Beatriz Cruz; https://lattes.cnpq.br/4777395189579793; Matos, Andreia Pereira; https://lattes.cnpq.br/6155202940087696; https://lattes.cnpq.br/8682457468741473
Water treatment plants (WTPs) are critical components of a municipality’s water supply system; they consist of the operational steps involved in treating surface water to ensure its quality and potability. One of these essential steps is coagulation, in which aluminum sulfate is commonly used. This coagulant presents both operational advantages and disadvantages for WTPs, raising the possibility of using plant-based polymers, such as lignin from corn stover. The objective of this study was to extract, modify, and apply lignin from corn stover as a coagulant and coagulation aid for turbidity removal. Extraction was performed using the soda pulping method, followed by chemical modification through oxidation with hydrogen peroxide. To validate the effects of the modification, the lignin was characterized using Ultraviolet-Visible Spectroscopy (UV-Vis), Nuclear Magnetic Resonance (¹H NMR), Thermogravimetric Analysis (TGA), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Energy-Dispersive X-ray Spectroscopy (EDS). Synthetic water was prepared, and batch Jar Tests were conducted using aluminum sulfate and lignin as primary coagulants to determine the optimal dosages for removal; subsequently, aluminum sulfate and lignin were applied as coagulation aids using the analysis of variance (ANOVA) methodology. The optimal dosages of aluminum sulfate were 80 mg. L⁻¹ for a settling time of 10 minutes and 50 mg. L⁻¹ for a settling time of 30 minutes; the lignins had no significant effect on turbidity removal, and their role as a coagulation aid was also ineffective, as confirmed by ANOVA with hypothesis testing (p-value > 0.05). Therefore, it was concluded that lignin was not capable of removing turbidity from the synthetic water within the predetermined times in the Jar Test. It is recommended that future studies use a turbidity level close to 100 NTU and evaluate the effects of lignin by altering the operational conditions of the Jar Test, such as pH.
Otimização e validação de métodos por cromatografia gasosa com detector de ionização por chama (GC-FID) para determinação de alcanos: uma revisão bibliográfica
(Universidade Federal de São Carlos, 2026-06-16) Santos, Isabela Pereira dos; Schio, Natali; http://lattes.cnpq.br/9916003002438166; Fadini, Pedro Sérgio; http://lattes.cnpq.br/3255060531838427; http://lattes.cnpq.br/8151301390180051
Alkanes constitute an important class of hydrocarbons widely used in environmental, petrochemical, and petroleum contamination monitoring studies. In this context, gas chromatography coupled with a flame ionization detector (GC-FID) stands out as one of the main techniques employed for the determination of these compounds due to its high selectivity, sensitivity, and reproducibility. The present study aimed to conduct a literature review on the optimization and validation of analytical methods using GC-FID for the determination of alkanes in different matrices. To achieve this, studies published in the scientific literature addressing parameters related to sample preparation, chromatographic conditions, and analytical validation criteria were analyzed. The results demonstrated that the optimization of factors such as oven temperature, carrier gas flow rate, and extraction conditions, that is, sample preparation procedures, directly influences the analytical performance of the method, contributing to improvements in chromatographic separation, sensitivity, reduction of analysis time, and minimization of matrix effects, thereby enhancing analyte quantification. The reviewed studies also highlighted the importance of employing statistical optimization tools, which enabled the simultaneous evaluation of multiple experimental variables and their interactions. Furthermore, the applicability of alkane determination in different matrices was observed, including environmental and food samples, highlighting its potential for hydrocarbon characterization in water, soil, and sediment samples, petroleum contamination monitoring, and authentication of products such as vegetable oils. In addition, the reviewed studies presented satisfactory results for validation parameters, including linearity, limits of detection, and limits of quantification, demonstrating the reliability of the technique. It can be concluded that GC-FID is an efficient analytical tool for the determination of alkanes, and that method validation is essential to ensure the quality and reliability of the obtained results.
Patrimônio cultural na região metropolitana de São José do Rio Preto (SP): diagnóstico territorial e análise das políticas públicas
(Universidade Federal de São Carlos, 2026-06-16) Maltarolo, Maria Heloísa; Guimarães, Camila Ferreira; http://lattes.cnpq.br/7623330251944001; https://orcid.org/0000-0002-6776-588X; Miyasaka, Elza Luli; http://lattes.cnpq.br/8353923902800804; https://orcid.org/0000-0003-4480-9672; http://lattes.cnpq.br/2054475756775420; https://orcid.org/0009-0002-3031-3625; Fialho, Beatriz Campos; Braga, Paula Marques; http://lattes.cnpq.br/8262918645325638; http://lattes.cnpq.br/9473603357991257; https://orcid.org/0000-0002-0339-1436; https://orcid.org/0000-0002-5315-1297
The intensification of urbanization and metropolitanization in Brazil has led to socio-spatial changes and the emergence of new urban demands, including growing concern with cultural and historical heritage assets, which culminated in a national heritage-making process. Contemporary society draws upon the past to shape its identity in the present, selecting and aligning memories with current values and objectives, so that cultural heritage encompasses diverse dimensions and principles, expressed through both tangible and intangible forms. This research aims to analyze the cultural heritage of the Metropolitan Region of São José do Rio Preto (MRSJRP) through a territorial diagnosis and an analysis of public preservation policies, seeking to understand the spatial distribution of cultural heritage assets, the existing protection instruments, and the challenges associated with heritage management at the metropolitan scale. The research is justified by the need to bring together the agendas of metropolitan planning and cultural heritage preservation, which have historically been addressed separately. In this context, the bibliometric analysis identified an increase in scientific production on heritage and metropolitan regions over the past five years and points to a research gap that remains insufficiently explored. The methodological strategy adopted consists of a case study and a qualitative approach, combined with theoretical and empirical research and cartographic analysis. These procedures enabled an understanding of the socio-spatial dynamics within which the region's cultural heritage assets are embedded. The results demonstrate that, although administrative structures dedicated to culture exist, mechanisms for the recognition, preservation, and protection of cultural heritage in the municipalities of the metropolitan region remain insufficient and fragmented. Challenges in urban legislation and limited social participation hinder the integration of heritage preservation, urban planning, and regional development, highlighting the need for more integrated cultural public policies that are responsive to the territorial specificities of the MRSJRP.