Chongqing Industry & Trade Polytechnic

This study presents a novel sensing platform that integrates modified electrodes with advanced computational anal. for rapid quality assessment of honeysuckle (Lonicera japonica) and other herbal products.A cost-effective electrode was prepared by drop-casting 10 μL of a 5 % nanomaterial ink onto a 0.126 cm² screen-printed electrode, followed by a 2-h drying process at ambient temperatureDifferential pulse voltammetry measurements conducted in 0.1 M PBS (pH 7.0) and ABS (pH 4.5) yielded distinct oxidation peaks; high-quality samples exhibited peaks at approx. 0.48 V in PBS and 0.42 V in ABS, whereas substandard specimens produced broader signals at around 0.52 V and 0.46 V, resp.An optimized extraction protocol using 0.1 g of powd. sample in 2 mL ethanol with a 10-min sonication step ensured efficient recovery of electroactive constituents.Stability testing over a 12-h period demonstrated current fluctuations confined within ± 2 %, and reproducibility assessments across five independent electrodes revealed a variation of less than 3 %.Multivariate statistical techniques, including PCA and LDA, enabled clear separation of sample clusters, while classification algorithms-MLP, NLSVM, and RF-achieved laboratory accuracies up to 92 % and 90.3 % in large-scale market tests.These performance metrics confirm that the integrated platform can reliably discriminate complex voltammetric profiles, offering a rapid and scalable solution for on-site quality control in resource-limited environments.The proposed method provides a promising alternative to conventional approaches and holds significant potential for revolutionizing quality assurance practices in the herbal medicine industry.

Nitrogen and sulfur codoped carbon dots (SB-CDs) were developed from sugar cane bagasse, an agro-industrial waste, and evaluated as an eco-friendly corrosion inhibitor for Q235B steel in HCl solution. The surface coverage of the adsorbed SB-CDs is strongly influenced by immersion time (6 and 72 h, both in static and dynamic conditions) and inhibitor concentration (20-200 mg/L). Maximum and uniform coverage is achieved with 150 mg/L SB-CDs. At this concentration, SB-CDs demonstrated a high inhibition efficiency of 96% after 6 h of immersion, maintaining effectiveness at 94 and 92% under static and dynamic conditions, respectively, at 72 h of immersion. Electrochemical studies showed that polarization resistance (R_p) increased, and corrosion current density (I_corr) of steel decreased in the presence of SB-CDs compared to uninhibited specimens, confirming SB-CDs' adsorption on metal surfaces. Additionally, surface analysis using scanning electron microscopy and atomic force microscopy confirmed the improved surface morphology and fewer corrosion features, supporting the formation of a protective film. Energy-dispersive X-ray and X-ray photoelectron spectroscopy analyses further confirm the formation of a protective layer by SB-CDs, attributed to the interaction of nitrogen-, oxygen-, and sulfur-containing functional groups with the steel surface. Therefore, a homogeneously adsorbed inhibitor layer entirely blocks the formation of iron chloride/oxide/hydroxide intermediates, ensuring high corrosion inhibition efficiency of Q235B steel in corrosive environments.

In recent years, controlled-release green corrosion inhibitors have become a research hotspot in the field of corrosion. In this study, chitosan/plant extract microcapsules (GCI@CS) loaded with Ambrosia artemisiifolia extract (green corrosion inhibitor, GCI) were prepared by emulsification cross-linking. Both the functional groups and micromorphology of GCI@CS were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and optical microscopy (OM). The loading capacity and encapsulation efficiency of GCI@CS were analyzed using UV-Vis spectroscopy. The corrosion inhibition performance of GCI@CS on carbon steel (C-steel) in 1.0 mol/L HCl was investigated using electrochemical impedance spectroscopy (EIS). The results indicated that GCI@CS, as a pH-sensitive microcapsule, can provide effective corrosion protection for C-steel in HCl solution. Notably, the corrosion resistance of GCI@CS improved with increasing concentration and time. The corrosion inhibition efficiency (η_EIS) of C-steel immersed in 1.0 mol/L HCl (with 500 mg/L GCI@CS) for 24 h reached 93.48 %. This study provides important insights for the industrial deployment of green corrosion inhibitors with controlled release properties.