Novel nicotinohydrazide based Schiff base ligands (L1–L3), derived from 2-methyl-6-(naphthalen-2-yl) nicotinohydrazide and substituted salicylaldehydes along with their Co, Cu and Ni complexes were synthesized and characterized. The ligands were obtained through a multistep synthetic route involving enaminone formation, heterocyclization, hydrazinolysis, and Schiff base condensation. Structural characterization was performed using UV analysis, FTIR, NMR and TGA analysis. Molecular docking against Staphylococcus aureus dihydropteroate synthase (PDB: 6CLV) and Escherichia coli DNA gyrase B (PDB: 4DUH) revealed favourable binding interactions, including hydrogen bonding, hydrophobic contacts, and π–π stacking. Density Functional Theory (DFT) studies provided insights into the electronic properties of the ligands and complexes. Antimicrobial evaluation demonstrated significant antibacterial and antifungal activities. Among the synthesized compounds, [Cu(L1)2] exhibited the highest activity against P. vulgaris and E. coli, while [Ni(L1)2] showed notable efficacy against S. aureus and Aspergillus flavus. Pyridine-coupled nicotinic hydrazide Schiff bases ligands and their metal complexes are synthesized and characterized by Mass FTIR, 1H, 13C NMR, UV analysis, TGA. Docking studies demonstrate that synthesized ligands bind to the microbial target site steadily. Density functional theory shows favourable stability and electronic properties of synthesized ligands and complexes. Selected derivatives display potent antibacterial and antifungal activity.
A dual-template magnetic ion-imprinted polymer based on halloysite (Fe₃O₄@HNT-DIIP) was synthesised via surface imprinting and co-precipitation. This material was utilised in magnetic solid-phase extraction (MSPE) to selectively and simultaneously concentrate cadmium (Cd2+) and lead (Pb2+) from both aqueous samples and environmental water sources. The morphological structure, crystallinity, and surface characteristics were analysed using Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and a zetasizer. The maximum adsorption capacities of Fe3O4@HNT-DIIP for Cd2+ and Pb2+ ions were 44.4 and 58.5 mg/g. The adsorption kinetics exhibited a strong correlation with the pseudo-second-order model, and the Langmuir isotherm suggested that the Fe3O4@HNT-DIIP adsorbent facilitates monolayer sorption on uniform sites. The Fe3O4@HNT-DIIP adsorbent proved selective towards Cd2+ and Pb2+ ions in the presence of Co2+ and Zn2+. Under optimum conditions, the Fe3O4@HNT-DIIP-MSPE coupled with inductively coupled plasma optical emission spectrometry (ICP-OES) exhibited wide linear ranges (0.712-100), acceptable limits of quantification (LOQs = 0.712–1.45 µg/L) and limit of detection (LODs = 0.214–0.440 µg/L) for Cd2+ and Pb2+ ions. The proposed method demonstrated excellent performance in preconcentrating and detecting trace metals in surface and groundwater samples, yielding recoveries of 95.5–102
Carbon quantum dots (CQDs) have emerged as a promising class of carbon-based nanomaterials owing to their chemical stability, low toxicity, excellent photoluminescence properties and superior water solubility. These unique physicochemical properties have enabled their widespread exploration in sensing, bioimaging, photocatalysis, optoelectronics and security applications. In recent years, green synthesis approaches utilizing biomass derived precursors have gained a lot of interest due to their sustainability, cost effectiveness and environmental compatibility. Agricultural wastes, fruit peels, plant extracts and other natural carbon sources have been extensively investigated for the ecofriendly fabrication of CQDs with enhanced optical performance. This mini review presents a concise overview of recent advances in the green synthesis of CQDs using ecofriendly methods such as hydrothermal, microwave assisted and pyrolytic techniques emphasizing on precursor selection and synthesis parameters influencing particle properties. The fundamental optical properties of CQDs including absorption characteristics, exciton dependent photoluminescence, emission mechanism and factors governing quantum yield enhancement are critically discussed. Furthermore, their emerging applications in fluorescent inks for anticounterfeiting and in metal ion sensing based on fluorescence quenching are highlighted. Finally, current limitations related to reproducibility, commercialisation and scalability are addressed along with future perspectives to improve performance, standardisation and practical implementation of CQD based technologies.
The high charge transfer resistance at heterogeneous solid electrolyte/electrode interfaces remains a critical bottleneck for all-solid-state batteries (ASSBs). While static structural disorder at these boundaries can suppress ionic transport, we explore a non-linear ondulatory framework, grounded in the Frenkel–Kontorova description of solitonic transport in superionic conductors, as a candidate alternative to this picture. Modeling the collective transport of alkali ions and their accompanying coordination-sphere distortion as an elasto-chemical soliton governed by the one-dimensional Non-Linear Schrödinger Equation (1D-NLSE), we investigate its dynamic interaction with a sharp interfacial barrier ( U_0 ) using a hybrid numerical scheme combining the Split-Step Fourier Method (SSFM) for bulk propagation and a localized Crank–Nicolson method at a regularized tanh (x) interface. We demonstrate, within this idealized 1D treatment, anomalous sub-barrier transmission ( v_0 < v_c ), with a smooth interfacial passage and scission into transmitted and reflected components. We relate the model’s parameters to reported migration barriers, elastic moduli, and kink effective mass for Li _10 GeP _2 S _12 , the only one of our reference materials with a confirmed quasi-one-dimensional Li ^+ conduction channel, and we postulate |ψ |^2 as proportional to a local elastic strain-energy density – a hypothesis motivated by a reported strain–conductivity relation and testable, in principle, by existing operando diffraction techniques. This work is presented as a preliminary, conceptual study: its extension to three-dimensionally conducting materials (Li _6 PS _5 Cl, LLZO) is offered as a qualitative interpretation only, and a quantitative mapping to first-principles and operando data remains necessary before any material-specific design conclusions can be drawn.
The infestation of Spodoptera frugiperda (fall armyworm) poses a serious threat to maize production in Egypt, necessitating effective phytosanitary strategies. Although chemical control remains widely used, its environmental risks and the growing problem of insect resistance have encouraged the adoption of phytosanitary irradiation (PI) as a sustainable alternative. This study aimed to evaluate the efficacy of gamma irradiation as a quarantine treatment against different developmental stages of S. frugiperda, and also assessing its impact on the nutritional and physicochemical properties of yellow maize. Eggs and larvae (third and sixth instars) were exposed to a range of gamma doses, and a large-scale confirmatory trial was conducted on 10,000 late-instar larvae at a target dose of 225 Gy. Additionally, the physicochemical stability of irradiated maize (225, 450 and 675 Gy) was examined using proximate chemical analysis, flavonoids and polyphenols, Fourier Transform Infrared (FTIR) spectroscopy, and Gas–Liquid Chromatography (GLC) for fatty acid profiling. The results indicated that late-instar larvae were the most radio-tolerant developmental stage, a dose of 225 Gy prevented the emergence of normal F1 adults under the laboratory conditions used in this study. In the large- scale confirmatory test, no normal adult emergence was observed among 10,000 irradiated sixth-instar larvae; however, the calculated confidence level was 63.2
