Scielo RSS http://scielo.pt/rss.php?pid=0872-190420250005&lang=en vol. 43 num. 5 lang. en http://scielo.pt/img/en/fbpelogp.gif http://scielo.pt http://scielo.pt/scielo.php?script=sci_arttext&pid=S0872-19042025000500269&lng=en&nrm=iso&tlng=en Abstract In this study, novel CuO/ZnO was synthesized using complex-directed hybridization and subsequent calcination (HNS/MWCNT). Then, they were employed as an electrochemical sensor for SFA. The synthesized CuO/ZnO was characterized using various techniques, including TEM, SEM, FT-IR, EDX, DPV and CV. Electrochemical studies revealed that HNS from CuO/ZnO/MWCNT modified electrode exhibited high A, more reactive sites and excellent electrochemical catalytic activity towards SFA oxidation, compared to GCE. The pH, modifier amount, SR and analyte Ct effects on oxidation ip were investigated, to optimize experimental conditions. LoD of 0.089 µM and linear calibration range from 0.1 to 1000 µM were obtained for SFA determination on HNS from CuO/ZnO/MWCNT/GCE. The modified electrode was successfully applied for SFA determination in WW, pharmaceutical and biological samples. http://scielo.pt/scielo.php?script=sci_arttext&pid=S0872-19042025000500289&lng=en&nrm=iso&tlng=en Abstract This research was conducted through color coronal spectral analysis (Ignatov, 2007). This method was employed under laboratory conditions, utilizing corona glow emitted by liquids and biological objects. The studies were performed with a high voltage of 12 kV and a high frequency of 15 kHz. In 1995, Antonov devised an apparatus with a transparent electrode for research with black-white photographic films. He named this method SHFD. In 2007, the device was improved by Ignatov and Stoyanov, for color Kodak films. Under specific electrical conditions, it is known as electrography. Notably, electrography forms the basis for the invention of the photocopier and the development of Xerox technology. EVOdrop water is a device authors use to transmit electromagnetic waves from 350 to 600 Hz, 20 to 40 kHz, and 7 Schumann frequencies under Color Corona Gas Discharge (CCGD) conditions. A comparative analysis of EVOdrop and tap water corona images was made. Furthermore, this analysis investigated physical and chemical processes occurring under high-frequency CCGD conditions. http://scielo.pt/scielo.php?script=sci_arttext&pid=S0872-19042025000500299&lng=en&nrm=iso&tlng=en Abstract CR of Cu in AS without and with 100 ppm NaCl was studied by electrochemical methods such as PDP technique, AC impedance spectra and EIS. The study revealed that, in the presence of excess of Cl ions in AS, CR of Cu decreased. This implies that people wearing ornaments or watches made of Cu must be careful about NaCl level in their sweat. http://scielo.pt/scielo.php?script=sci_arttext&pid=S0872-19042025000500309&lng=en&nrm=iso&tlng=en Abstract Environmental and health issues have created the urgent need to transition from CrO₄² - legacy to more environment-friendly CC. The various international protocols on CrO₄² - have restricted its usage, thus opening a floodgate of research activities on its urgent replacements. The current study which examines HSCE and V salt takes a cue from earlier outcomes in which a hybrid HSCE and M2MoO4 coating outperformed CrO₄² - coating. The relatively faster diffusion rate of the chelated Mo (VI) complex of hybrid HSCE over Cr (VI) inhibited corrosion and provided a better barrier on the substrate. Thus, this study examined HC from HSCE in combination with V salt, a V salt-based CC and untreated Al 6061. From PDP measurements and EIS studies in a 3.5% NaCl solution, CC from VO4 outperformed HC, and both outclassed untreated 6061 Al. Rct values from EIS studies were 116 (lowest), 1825 and 3434 ohm/cm2 (highest) for uncoated 6061 Al, HSCE/VO4 coating and VO4, respectively. From PDP studies, icorr values were 24.934 x 10-6 (VO4), 33.275 x 10-6 (HSCE/VO4) and 36.64 x 10-6 A/cm2 (6061 Al), respectively, compared to 1.6 x 10-6 A/cm2, for CC from CrO₄², in a similar study. These primary findings might support new opportunities for producing environment-friendly smart hybrid and mono CC based on V compounds for corrosion control on Al in the metal finishing industries. http://scielo.pt/scielo.php?script=sci_arttext&pid=S0872-19042025000500323&lng=en&nrm=iso&tlng=en Abstract Bm has the best role in the economy of a country. Ln is an essential structural component that is present in all vascular plants’ cell walls. It is essential for the development of connective tissues, since it gives stiffness, strength and resistance to external threats like infections. Ln has numerous economic uses, and its extraction might lead to the development of several novel applications. Therefore, it is of the utmost significance to develop efficient and long-lasting solutions for Ln extraction from Bm. For this reason, one of the goals of the current study was to examine optimized Ln extraction from Bm, SB, rice and WS, by chemical methods. Further, Ln chemical extraction process characterization, optimization, and its applications in resins have herein been carried out.