Hindustan Institute of Technology and Science (HITS), formerly Hindustan College of Engineering, is a private deemed-to-be-university headquartered in Chennai, India. It was founded in 1985 by K.C.G. Verghese and was conferred the "University Status" status from the University Grants Commission Under Section 3 of UGC Act 1956 from the academic year 2008-09 and under the name HITS (Hindustan Institute of Technology and Science). It is a member of the Hindustan Group of Institutions which also includes the Hindustan Institute of Engineering Technology, KCG College of Technology, Hindustan College of Arts and Science and more.
MgFe1.9X0.1O4 (X = Bi, Cu, Nd, Ni) spinel ferrites have been prepared by a combustion process and their structural, optical, and magnetic characteristics have been studied in detail. X-ray diffraction (XRD) and Rietveld refinement established the single-phase cubic spinel structure (Fd-3 m) with the lattice parameters within the range of 8.3843–8.4051 Å, and the FTIR analysis confirmed the occurrence of typical Fe–O and M–O vibrational modes which determined the formation of spinel ferrites. The existence of a tunable band gap between 1.74 and 1.85 eV was observed through optical analysis, and the optical conductivity at the visible and near-infrared spectrum was increased by defect states introduced by the dopant and charge carrier generation. The visible emission in photoluminescence (PL) spectra were found to have an intensity and wavelength change based on the dopant, and enabled by CIE chromaticity analysis, showed tunable emission properties. Magnetic measurements have shown that the incorporation of dopants has a significant effect on the magnetic behavior, where the saturation magnetization is up to 0.338 emu g−1 and the coercivity is between 127 and 155 Oe. The observed changes can be explained by the cation redistribution and altered super exchange interactions. The findings in general indicate that using controlled incorporation of dopants allows optical and magnetic characteristics to be tuned in tandem, and thus the capacity of MgFe1.9X0.1O4 ferrites to possess multiple functionalities. The materials have the potential to be used in optoelectronic, sensing, and spintronic systems.
The hydrothermal durability of hybrid epoxy composites reinforced simultaneously with surface-modified pineapple fiber, a PET core, and nutmeg husk biochar remains largely unexplored, particularly under prolonged warm water exposure. To address this gap, five composite formulations were fabricated. The unaged composite was designated as E24, while the remaining samples (EW0-EW3) were subjected to different aging conditions. Subsequently, the composites were evaluated for their mechanical properties, creep behavior, and water absorption characteristics, thermogravimetric, and morphological properties. Among all formulations, E24 exhibited the highest performance retention, with tensile strength of 131 MPa, flexural strength of 145 MPa, impact strength of 4.27 J, and hardness of 81 Shore D. It also showed the lowest creep strain (0.0059–0.0084 at 5000 to15000 s) and minimal water uptake (1.26
Abstract The objective of this research was to evaluate the effectiveness of silane surface treatment as a failure mitigation strategy for epoxy composites reinforced with Ixtle fiber, a PET core and Elaeocarpus ganitrus husk biochar when subjected to prolonged service temperature exposure. Accordingly, untreated, silane treated and thermally aged composites were fabricated and conditioned at 50 °C for durations of 7 days, 14 days, 30 days and 90 days. Mechanical, fatigue and drilling behaviours were systematically investigated supported by microstructural interpretation. The results show that silane treatment significantly improves the initial mechanical, fatigue and drilling performance by enhancing fiber matrix interfacial bonding. However, with increasing service temperature duration, all mechanical properties exhibit a gradual decline due to matrix degradation and interfacial weakening. Even so, silane treated composites retained superior mechanical and fatigue performance compared to untreated composites with strength retention remaining within an acceptable range after up to 90 days of exposure at 50 °C. Drilling results further confirm reduced hole enlargement and improved dimensional stability in treated systems despite thermal ageing. Overall, the findings highlight that silane surface treatment effectively delays thermally induced damage and preserves functional performance over extended service durations thereby, demonstrating its practical relevance for polymer composites intended for moderately elevated temperature applications.
This study investigates the indentation behavior of stitched hybrid carbon-glass quadraxial laminates with varying thickness under hemispherical, conical and flat indenters. The experimental results show peak load and energy absorption increased with laminate thickness, where thicker laminates exhibited an increase of 30–40
The study presents the successful synthesis and crystallization of a square pyramidal copper(II) complex coordinated with glycine in its zwitterionic form [CuS_2(C_4H_10N_2O_4)]_2(C_2H_5NO_2)_2 (1), as confirmed by single crystal XRD study. The complex crystallizes in an orthorhombic system with space group Pna2_1 , exhibiting a tetracoordinated copper center bound to oxygen and sulfur atoms in a cis-square planar geometry. The crystal structure is stabilized by a comprehensive grid of hydrogen bonds involving N–H ⋯ O and N–H ⋯ S interactions, which form characteristic graph-set motifs and contribute to a three-dimensional zig-zag molecular packing. FTIR confirmed glycine coordination and Cu–N/Cu–S bonding. Thermogravimetric analysis reveals that the title compound is thermally stable up to 86 ^∘C , adequate for room-temperature lasing applications, and its subsequent decomposition further supports the elemental composition of the material. UV–Visible spectra showed a strong peak at 208 nm, an absorption edge at 237 nm, and a wide band gap of 5.55 eV, indicating high electronic stability. Photoluminescence revealed broad emission from 370 to 532 nm, deconvoluted into ligand-centered, ligand-to-metal, and metal-centered transitions, demonstrating efficient energy redistribution within the complex. Glycine, in its zwitterionic form, acts as a bidentate ligand coordinating with transition metals to form complexes exhibiting nonlinear optical behavior, including nonlinear absorption, refraction, and excited-state transitions through metal-ligand charge transfer. The nonlinear optical studies by Z-scan revealed self-defocusing behavior and efficient optical limiting. The measured nonlinear refractive index n_2 was 2.786× 10^-8 cm^2 W^-1 , and the nonlinear absorption coefficient β was 0.92× 10^-4 cm W^-1 . The third-order nonlinear optical susceptibility χ ^(3) was found to be 2.46× 10^-6 esu, demonstrating significant third-order nonlinear response. Optical limiting measurements showed an onset threshold of 1.545× 10^3 W cm^-2 proving the material’s ability to shield optical devices from high-intensity light.
