Impedimetric D-Xylose and D-Arabinose sensors was development from composite electrodes of graphite and histological paraffin, modified with functionalized multi-walled carbon nanotubes (FMWCNTs) based on molecular imprinted poly-o-phenylenediamine (poly-o-PD). The contribution of this work was not only the development of a D-xylose and D-Arabinose MIP impedimetric sensor with good performance, but also the electrodeposition method for FMWCNTs onto surface of graphite composites electrodes with ease of control and reproducibility of the electrodeposition process. The sensors were characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), field emission gun scanning electron microscopy (FEG-SEM) and RAMAN spectroscopy. The MIPs sensors for the pentoses have good selectivity, sensitivity in the concentration range of 1.0 × 10 ⁻¹¹ to 1.0 × 10 ⁻¹⁰ mol l ⁻¹ with limit of detection (LOD) of 4.50 × 10 ⁻¹² mol l ⁻¹ for D-Xylose and 4.25 × 10 ⁻¹² mol l ⁻¹ for D-Arabinose. MIPs was applied to determination of pentoses in samples of sugarcane bagasse hydrolysates using the standard addition method and validated by recovery study, which presented satisfactory results between 92.9% and 115.5%.

The cashew tree (Anacardium occidentale) is one of the most important crops in Brazilian fruit production, with significant economic, social and environmental importance, especially in the semiarid region of the Northeast, responsible for 99.7% of national production. The activity generates approximately 100 million dollars per year, being a strategic source of income for small producers. Despite the nutritional and sensory potential of the pseudofruit, its underutilization still represents significant losses. The full use of the plant, including the nut, pseudofruit and residues, offers opportunities in industries such as food, beverages, cosmetics and biocomposites. In this scenario, the dwarf cashew tree stands out as a promising alternative, due to its adaptation to adverse climates and contribution to family farming. This article analyzes the challenges and potential of the crop, considering its role in the sustainable development of vulnerable regions of Brazil.

The sensors modified carbon nanotubes and molecularly imprinted polymers are an excellent choice for the determination of D-arabinose, because they have high selectivity and sensitivity for analysis. This allows the control and optimization of the second generation ethanol production process, given the clear understanding of the chemical changes that occur through the hydrolysis of lignocellulosic biomass. For this reason, the present work presents a chemical study of the functional groups of the chemical species present on the sensor surface by the Fourier transform infrared spectroscopy (FT-IR) technique and a morphological analysis by the scanning electron microscopy (SEM) technique.

Com o crescimento da população e o aumento da demanda por energia surge a necessidade de desenvolvimento de fontes alternativas energia. O biometano, obtido a partir da purificação do biogás, que pode ser retirado da decomposição resíduos sólidos urbanos, presente em quantidades abundantes em muitas cidades brasileiras, tem se despontado como uma interessante alternativa a fim de complementar a utilização combustíveis gasosos, visto que o principal combustível utilizado atualmente é o gás natural, de origem fóssil e com impactos ambientais negativos em sua extração. Este trabalho promove a análise da viabilidade energética e ambiental da utilização do biometano para a injeção na rede de gás de natural, a partir de ferramentas de simulações computacionais. Os resultados obtidos, indicam que as emissões dos gases da combustão do gás natural e do biometano são praticamente equivalentes e, a diferença nos valores de temperatura de chama entre os combustíveis é de cerca de 7,1%. Assim, a inserção do biometano na rede de gás natural, além de não implicar no aumento de impactos ambientais também não promove perdas significativas nas características energéticas da mistura.

To guide sustainable cashew cultivation, this study evaluated the nutritional dynamics and environmental interactions of five cashew clones across two contrasting pedological environments (clay-rich vs highly sandy) acting as extreme case studies within the Amazon Savanna (Roraima). By analyzing soil profiles (0–40 cm) and foliar nutrient concentrations, we identified extreme spatial heterogeneity. In the clay-rich soils of Normandia, severe acidity and high exchangeable aluminum were observed, alongside higher soil organic matter (SOM) and significantly greater foliar K accumulation across all clones, while N and P increases were genotype-specific. Conversely, the highly sandy soils (>80% sand) of Bonfim exhibited characteristics associated with nutrient leaching risks. Principal Component Analysis explained 81.6% of the data set’s total variance (PC1:69.3%; PC2:12.3%), revealing an absolute clustering of samples by cultivation environment rather than by genotype. This suggests that local edaphic conditions strongly shape the crop’s nutritional signature. We hypothesize that SOM acts as a key buffer in these environments, potentially mitigating Al stress and reducing nutrient loss. Clone BRS 274 demonstrated stable nutritional performance in Normandia, while clone CCP 09 exhibited physiological responses adapted to the sandy soils of Bonfim.

In order to mitigate the impacts caused by the rampant consumption of fossil fuels, many countries are investing in the development and optimization of alternatives that minimize dependence on fossil energy. The second generation of ethanol (2G), characterized by its relevant production potential, is considered a good alternative, which can be produced from sugarcane bagasse. Therefore, it is extremely important to evaluate the efficiency of 2G ethanol production processes, mainly in the compositional analysis of hydrolysates from the pre-treatment of lignocellulosic biomass, to promote greater production. Thus, the development of electrochemical sensors composed of graphite/paraffin composite electrodes coated with multi-walled carbon nanotubes (MWCNTs) modified with molecularly imprinted polymers (MIPs) are an excellent option for carrying out rapid analyzes. Due to the highly sensitive electrical properties of the MWCNTs and the molecular impression of the polymers that allow a high affinity with the model molecule, the sensor has high selectivity, good sensitivity and reproducibility for the determination of ferulic acid. For this reason, the present work, using the Scanning Electron Microscopy (SEM) and Cyclic Voltammetry (CV) technique, presents remarkable morphological characteristics of the sensor surface and its electrochemical behavior in relation to the electropolymerization process and speed increase of the scan.