http://repositorio.ufgd.edu.br/jspui/handle/prefix/51 Sat, 05 Sep 2026 00:28:15 GMT 2026-09-05T00:28:15Z http://repositorio.ufgd.edu.br/jspui/handle/prefix/7048 Título: Desenvolvimento de tecnologia magnética de baixo custo para remoção de microplásticos usando Luffa Cylindrica Autor(es): França , Roberta Sorhaia Samayara Sousa Rocha de Primeiro Orientador: Muzzi , Rozanna Marques Abstract: Microplastics in the environment are becoming ubiquitous, and their widespread distribution in aquatic environments poses a global environmental concern. Given the rising trend of this contamination, it is necessary to develop removal technologies that combine efficiency with low cost. In this context, adsorption combined with magnetic separation emerges as a promising strategy, as it enables both the capture of microplastics (MPs) and the recovery of the adsorbent from the aqueous medium. Thus, this study aimed to develop and evaluate a magnetic bioadsorbent—designated LCMAGNaOH—composed of Luffa cylindrica (LC) fruit (commonly known as vegetable sponge) modified with NaOH and combined with natural micrometric magnetite (MAG), for the removal of polystyrene (PS) and polyethylene terephthalate (PET) microparticles. Synthesis was carried out without organic solvents and at temperatures below 100 °C. The resulting material was characterized using physicochemical and morphological techniques—including scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD)—to assess its morphology and confirm the presence of the magnetite phase. The removal efficiency of LCMAGNaOH was evaluated using PS and PET MPs ranging from 75 to 600 µm in size across three aqueous matrices: drinking water, simulated seawater, and water collected from a eutrophic lake in Dourados, Mato Grosso do Sul, Brazil. Tests were conducted with short contact times and without continuous agitation, and residual MP concentrations were determined via ultraviolet-visible (UV-Vis) spectroscopy and gravimetry. Additionally, the stability of the magnetic phase, the recovery of the bioadsorbent via magnetic separation using a neodymium magnet, and its reusability over three cycles were evaluated. LCMAGNaOH demonstrated high removal capacity with a short contact time, achieving approximately 82% for PS and 81% for PET within 10 minutes. Magnetic separation also enabled the recovery of over 90% of the material mass, demonstrating the feasibility of its removal from the aqueous medium after treatment. The results show that LCMAGNaOH is an efficient magnetic bioadsorbent for capturing microplastics in various aqueous matrices, representing a promising strategy for microplastic removal in aquatic environments.magnetic separation, representing a promising strategy for microplastic removal in aqueous environments. Editor: Universidade Federal da Grande Dourados Tipo: Tese Tue, 11 Aug 2026 00:00:00 GMT http://repositorio.ufgd.edu.br/jspui/handle/prefix/7048 2026-08-11T00:00:00Z http://repositorio.ufgd.edu.br/jspui/handle/prefix/7013 Título: Desenvolvimento e caracterização de filme polimérico produzido a partir de gelatina de pele detilápia (Oreochromis niloticus) contendo lignina encapsulada Autor(es): Eberhart, Markus Rafael Carvalho Primeiro Orientador: Paz, Marcelo Fossa da Abstract: The development of biodegradable films from agro-industrial waste represents an alternative to conventional synthetic polymers. This study aimed to develop and characterize films based on gelatin obtained from Nile tilapia (Oreochromis niloticus) skin, containing lignin encapsulated by pectin (LP). The gelatin showed an extraction yield of approximately 16%. The films were produced via casting using formulation M4, composed of 5% gelatin, 1% glutaraldehyde, and 0.6% glycerin, as well as formulations M4 + LP 0.2% and M4 + LP 1.0%. Colorimetric and mechanical properties, solubility, biodegradation, and spectroscopic characteristics (UV-Vis diffuse reflectance, fluorescence, and FTIR) were evaluated. Quantitative data were analyzed using descriptive statistics, ANOVA, and Tukey's test, with a significance level of 5%. Tensile strength was 8.00 MPa for M4, 7.68 MPa for M4 + LP 0.2%, and 10.04 MPa for M4 + LP 1.0%, demonstrating an increase of approximately 25.5% in the formulation with the highest LP concentration. Conversely, elongation decreased from 87.04% to 40.88% and 16.75%, respectively, indicating increased rigidity and reduced matrix mobility. The average mass gain in the permeability test was 0.1579, 0.1549, and 0.1212 g·day⁻¹ for M4, M4 + LP 0.2%, and M4 + LP 1.0%, respectively. Water vapor permeability decreased from 4.0062 to 3.9301 and 3.0758 g·mm·m⁻²·day⁻¹·kPa⁻¹, corresponding to a reduction of approximately 23.2% for M4 + 1.0% LP. Average solubility showed a slight decrease, from 18.83 ± 1.78% to 18.27 ± 2.07% and 17.94 ± 0.83%, with no significant difference according to ANOVA (F = 0.374; p = 0.695). In the soil burial test, the films lost integrity before a complete mass curve could be obtained, with disintegration and the presence of mycelium observed by the sixth day. Regarding diffuse reflectance, the average value in the UV region dropped from 6.12% to 4.87% and 2.05%. The maximum Kubelka–Munk function increased from 9.02 to 11.22 and 28.42, representing a 214.9% increase for the formulation with 1.0% LP and indicating greater ultraviolet radiation attenuation. In fluorescence analysis, peak maxima remained between 495.5 and 497.0 nm, but intensity decreased from 3198 a.u. to 1859 and 1301 a.u., corresponding to quenching rates of 41.87% and 59.32%. The full width at half maximum (FWHM) ranged from 76.6 nm for the control to 84.1 nm for M4 + 1.0% LP. FTIR analysis confirmed characteristic bands for gelatin, lignin, and pectin without the formation of new detectable functional groups, suggesting predominantly intermolecular interactions. The pectin exhibited an estimated degree of methylation between 40% and 46%, classifying it as low-methoxyl pectin. It is concluded that M4 + 1.0% LP exhibited the best performance regarding barrier properties, mechanical strength, and optical protection, albeit with a marked loss of flexibility. Editor: Universidade Federal da Grande Dourados Tipo: Dissertação Tue, 28 Jul 2026 00:00:00 GMT http://repositorio.ufgd.edu.br/jspui/handle/prefix/7013 2026-07-28T00:00:00Z http://repositorio.ufgd.edu.br/jspui/handle/prefix/6971 Título: Temimbo'e Guarani/Kaiowá kuéra ñomongeta joja ombosyrývo peteĩ tembiapo papapy rehegua Autor(es): Franco, Gerson Primeiro Orientador: Rodrigues, Renata Viviane Raffa Abstract: Ko tembiapo ha'e peteĩ mba'eporandu Mestrado rehegua. Oñepyrũ mbo'ehára ha tembikuaarekahára ohechakuaa rupi oĩha heta temimbo'e kuéra mbo'eharenda indígena Amambai-MS pegua, Ensino Médio-pe ohasa asy papapy rehegua jekuaa hag̃ua. Umi apañuãi ojehecha ojehupytyha hetave okyhyje rupi oñe'ẽ hag̃ua, ndoikuaaporãi jave mba'épa mbo'ehára omyesakãva. Ko mba'eporandu oñemopyenda teoría sociocultural rehe, ha tenonderãite ñomongeta joja rehegua ha Ensino Exploratório jehecha rehe. Ko apañuãi rehe oñeheka hag̃ua peteĩ tape pyahu, ko mba'eporandu omboguata mbo'epy ñemboguata ko jehecha rupive, ikatu hag̃uáicha oñentende mba'éichapa ñomongeta joja oipytyvõ temimbo'e Guarani-Kaiowá kuéra, 1º ary Ensino Médio pegua, peteĩ mbo'eharenda Reserva Indígena Amambai MS pegua, ikatu hag̃uáicha oikuaa porãve papapy rehegua. Ko mba'eporandu rupive, oñeha'ã ojekuaa mba'éichapa temimbo'e Guarani-Kaiowá kuéra omoheñói hekoguata ha tapekuéra ombosyry hag̃ua peteĩ tembiapo yvyra'anga peteĩcha rehegua área rehegua. Ko mba'eporandu rape oñemopyenda tembikuaareka qualitativa rehe, ha ojepuru etnografia rehegua rape ojehechakuaa hag̃ua temimbo'e kuéra ñomongeta, ojuehegua jekuaa ha umi he'iséva mbo'eharóga ryepýpe. Umi mbo'epy oñeñongatu hendayvúpe (áudio), ha umi marandu ojeporavóva oñembohai Guarani ñe'ẽme ha upéi oñembohasa portugués ñe'ẽme. Umi jehechapyre ohechauka temimbo'e kuéra oikuaa porã hague heta mba'e iñimportánteva geometria rehegua, ombojoajúvo umíva hekove tee rehegua ndive, ha ohechauka hag̃ua ojapo hag̃ua ita'i ñemohenda peteĩ óga ñemopu'ãme. Upéicha avei ohechauka hikuái arandu oguerekóva mba'éichapa oñembojoaju térã oñemboja'o umi ta'anga peteĩcha rehegua ikatu hag̃uáicha ojekalkula área. Upévare, pe tembiapo rekopy ha mbo'ehára rembiapo omoirũ ha oipytyvõ hag̃ua temimbo'e kuéra ñemoarandu, oipytyvõ temimbo'e kuéra oike hag̃ua kyre'ỹme tembiapópe ha oñomongeta joja hag̃ua, omoheñói hag̃ua hekoguata iñambuéva ombosyry hag̃ua pe tembiapo. Upévare avei, temimbo'e kuéra ñomongeta ojuehe apytépe ha'e kuri mba'e tuichavéva papapy rehegua ñemoarandúpe, mba'érehepa ha'ekuéra voi oporandu, ome'ẽ hemiandu, omoneĩ térã ndojoguái peteĩ ñe'ẽre, ha ohecha porã umi tape iñambuéva ojepurúva ombosyry hag̃ua pe tembiapo. Koichaite rupi, pe ñomongeta ha tembiapo oñondive oipytyvõ ojeheja hag̃ua kyhyje oñe'ẽvo, ha avei omopu'ã hag̃ua arandu oñondivepa área rehegua. Editor: Universidade Federal da Grande Dourados Tipo: Dissertação Tue, 23 Jun 2026 00:00:00 GMT http://repositorio.ufgd.edu.br/jspui/handle/prefix/6971 2026-06-23T00:00:00Z http://repositorio.ufgd.edu.br/jspui/handle/prefix/6970 Título: Uma análise das atividades experimentais nos livros didáticos de ciências da natureza do ensino médio Autor(es): Hsuan, Tseng Hsiao Primeiro Orientador: Simões , Bruno dos Santos Abstract: This dissertation aimed to investigate the approaches to experimental activities in high school science textbooks, focusing on the Chemistry curricular component. The research is qualitative and documentary in nature, using Bardin's (2016) content analysis method on seven collections approved by the 2021 PNLD. This edition was chosen because it is the first aligned with the BNCC guidelines. The results indicate that the investigative approach is less prevalent than the illustrative, conceptual, and technical approaches, highlighting room for improvement in teaching materials. This highlights the role of teachers in adapting these proposals to a more investigative approach, despite the challenges imposed by the school environment, such as planning time and the high demand for content to be covered. The conclusion is that, although the books analyzed promote intellectual autonomy and intermediate critical reflection among learners, the use of textbooks as a resource and educator-mediated experimentation remain valuable tools for learning. Editor: Universidade Federal da Grande Dourados Tipo: Dissertação Thu, 28 Aug 2025 00:00:00 GMT http://repositorio.ufgd.edu.br/jspui/handle/prefix/6970 2025-08-28T00:00:00Z