The steel-concrete composite beam is characterised as an effective and efficient structural member for most structural applications. Under sagging bending, slip strain in the concrete flange of a composite beam prevents the cross-section from remaining plane, resulting in a non-uniform distribution of normal stress across the flange width. The non-uniform distribution of normal stress, referred to as the ‘shear lag effect’, is addressed in design practice through the adoption of the effective width concept. The national and international code specifications recommend a simplified approach based on experimental and analytical investigations to address this shear lag effect. The proposed effective width expression predominantly depends on the beam span and end conditions. However, the effective width was influenced by several other parameters like beam span, slab width, beam end conditions, slab thickness, loading type, degree of shear connection, etc. This study examines the influence of stud orientation on the estimation of effective width in composite beams with solid slabs. A numerical investigation was conducted for various stud connector arrangements within the slab, and the resulting effective widths were compared. The findings indicate that the Indian code of practice tends to underestimate effective width compared to the specifications outlined in EUROCODE 1994.
The polycrystalline compound Nd2CoFeO6 (NCFO) was prepared by the conventional solid-state method to explore its structural and optical properties. The Vibrational characteristics and Photoluminescence properties of the NCFO double perovskites has been investigated for the first time. The structure was elucidated by X-ray powder diffraction (XRD), revealing that this double perovskite forms a single-phase orthorhombic phase in the pnma space group. Evidence of spin–phonon coupling in NCFO was detected through Raman spectroscopy analysis. Results from Raman studies and group theory confirm that NCFO possesses Raman-active modes. The excitation and emissions of NCFO photoluminescence were investigated. The results indicate that the phosphor can be excited over the wavelength range 250—450 nm, emitting violet-blue light at 406 nm via the transition 4D7/2 → 4I9/2.The results showed that the NCFO double perovskite has significant potential for use in opto-electronic and sensor devices.
An indole-based Schiff base chemosensor, L = (Z)-2-((((1H-indol-4-yl)methyl)imino)methyl)-6-methoxyphenol, has been developed for the detection of Cu2+, Al3+, and Cr3+ ions at low concentrations, offering potential applications in environmental monitoring and health safety. The chemosensor exhibits distinct absorption changes upon binding these target metal ions in a CH3CN/H2O (1:1, v/v) mixture, while other tested cations and anions produce negligible spectral responses. The detection limits were determined to be 0.45 mu M for Cu2+, 0.71 mu M for Al3+, and 0.64 mu M for Cr3+, with a 2:1 ligand-to-metal binding stoichiometry confirmed by Job's plot, ESIMS, NMR, and IR titrations. DFT studies indicate a significant decrease in HOMO-LUMO energy gaps upon complex formation, reflecting strong ligand-metal interactions. Additionally, docking studies demonstrate high binding affinity of L and its complexes toward DNA and HSA, providing insight into potential biological applications. Furthermore, the practical applicability of L was validated through successful detection of Cu2+ and Al3+ ions in real water samples, demonstrating its potential for environmental monitoring.
The application of photocatalytic technology offers a promising solution to address environmental pollution, particularly for degrading organic contaminants. Recent research in this field has focused on developing visible-light-responsive photo catalysts with enhanced efficiency and stability. In the present study, a novel CuFe2O4-CeO2-h-BN ternary nanocomposite was successfully synthesized using ultrasonic and hydrothermal methods, resulting in a well-structured heterojunction architecture. The prepared material structural and surface morphologies were characterized by XRD, Raman, SEM, TEM, XPS and BET analysis. Optical analyses demonstrated a systematic reduction in band gap values from pristine CuFe2O4 (1.47 eV) to CuFe2O4-CeO2 (1.31 eV), CuFe2O4-h-BN (1.24 eV), and ultimately to CuFe2O4-CeO2-h-BN (1.05 eV), indicating significantly improved visible-light absorption capability of the composite material. The photocatalytic activity was assessed by monitoring the degradation of methylene blue (MB) and methyl orange (MO) under visible light irradiation. Meanwhile, CuFe2O4-CeO2-hBN ternary nanocomposites were tested for their antibacterial assay using the agar well diffusion method, against E. coli, P. aeruginosa, B. subtilis S. aureus. The ternary composite exhibited outstanding degradation efficiencies of 94% for MB and 95% for MO within 120 min, surpassing the performance of both binary and pristine photocatalysts. The enhanced photocatalytic efficiency is attributed to the synergistic interaction among CuFe2O4, CeO2, and h-BN, which facilitates effective charge separation and light harvesting. The ternary nanocomposite CuFe2O4-CeO2-hBN is effective for the photodegradation of dyes. Furthermore, CuFe2O4-CeO2-hBN exhibited remarkable antibacterial efficacy, particularly against harmful bacteria like E. coli, P. aeruginosa, B. subtilis, and S. aureus.
In this study, we report an aminobenzamide-based Schiff base probe, designated as L [(E)-2-((2,3-dihydroxybenzylidene)amino)benzamide], developed for the selective and sensitive recognition of Cu2+, Al3+, and Fe3+ ions. The interaction of L with various metal ions was systematically investigated using UV-Visible spectroscopy. The UV-Vis analysis revealed the effective detection of Cu2+, Al3+, and Fe3+ ions, establishing L as a colorimetric probe in a DMSO: H2O (1:1, v/v) solvent system. Upon metal coordination, new absorption bands emerged at 418 nm (Cu2+), 388 nm (Al3+), and 680 nm (Fe3+). These bands originate from metal-induced modulation of the ligand’s native intramolecular charge-transfer (ICT) transition. Coordination through the phenolic oxygen, imine nitrogen, and amide nitrogen withdraws electron density from the donor segment, thereby altering and partially restricting the ICT process and generating distinct metal-specific charge-transfer transitions. The detection limits were determined to be 0.90 µM for Cu2+, 0.51 µM for Al3+, and 0.45 µM for Fe3+. Job’s plot analysis and electrospray ionization mass spectrometry (ESI-MS) confirmed a 1:1 stoichiometric complexation between L and each of the target metal ions. The proposed coordination modes were further supported by density functional theory (DFT) calculations. Moreover, the practical utility of L was validated through successful detection of trace Cu2+, Al3+ and Fe3+ ions in environmental water samples.
