Sri Venkateswara College of Engineering

Alzheimer’s disease (AD) is one of the most common forms of dementia. AD is associated with memory loss and cognitive decline. Several research works have been carried out to treat AD. However, currently available treatment options are only useful in the treatment of the individual pathology of AD but not useful in disease modification. Recent research works have identified the associated effects of neuroinflammation, oxidative stress, and glial cell dysfunction in AD pathology. Aspirin is one of the most commonly used NSAIDs in the treatment of several inflammatory diseases. Aspirin inhibits cyclooxygenase (COX) enzymes through an irreversible pathway. However, aspirin also exhibits other important pharmacological properties. This review aims to highlight the potential of aspirin-based multi-target directed ligands in the regulation of AD pathology through the regulation of neuroinflammation and oxidative stress. Schematic overview of aspirin and aspirin-derived multi-target-directed ligands (MTDLs) targeting interconnected pathological processes in Alzheimer’s disease, including neuroinflammation, oxidative stress, glial activation, and amyloid-β–associated dysfunction.

This study presents a detailed investigation of Ni/Cu/Fe2O3:Bi2O3/n-GaN metal–oxide–semiconductor (MOS) heterojunctions, focusing on their structural, chemical, and electrical properties. Fe2O3:Bi2O3 composite films were successfully deposited on n-GaN substrates, as confirmed by glancing-angle X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), which verified the film’s crystallinity, composition, and the formation of a uniform insulating layer. XPS further confirmed the presence of key elements and proper interface formation between the metal electrodes and the semiconductor. Electrical measurements revealed that the MOS exhibited clear rectifying behavior with reduced leakage current compared to the conventional Schottky junction (SJ). Analysis of key parameters including Schottky barrier height (Φb), ideality factor (n), and series resistance (Rₛ) was conducted using multiple extraction methods (Cheung’s, F(V)–V, and ΨS–V), all showing good agreement. The forward I–V characteristics of both SJ and MOS HJs demonstrated ohmic behavior at lower voltage regions, transitioning to space-charge-limited conduction (SCLC) at higher voltages. This transition confirms the influence of interface states and trap-assisted conduction in determining the electrical transport mechanism. These results demonstrate the effectiveness of Fe2O3:Bi2O3 nanocomposites as insulating layers in GaN-based MOS devices and underscore their potential for future optoelectronic applications.

The quest for high-efficiency and stable photoanodes remains a central challenge in dye-sensitized solar cells (DSSCs). Here, we report a hierarchical CNT-integrated lithium–zinc–aluminate (CNT–LiZn0.5Al2O4) spinel nanoarchitecture as a superior alternative to conventional CNT–ZnO and CNT–LiZn0.5O photoanodes. Using a combination of SILAR and doctor blade techniques, the nanocomposites were fabricated on FTO substrates and thoroughly characterized. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses confirmed successful Li⁺ and Al3⁺ incorporation, driving a structural transition from wurtzite ZnO to a cubic spinel phase, effectively passivating defect states and tuning the electronic structure. UV–Vis Tauc analysis revealed significant bandgap narrowing from 3.04 eV (CNT–ZnO) to 2.34 eV (CNT–LiZn0.5Al2O4), thereby enhancing visible-light absorption. AFM and SEM studies further showed a highly textured, porous morphology, favorable for dye loading and light scattering. Combined with the CNT network’s superior charge transport, this structural and electronic synergy led to pronounced recombination suppression, as evidenced by quenched PL spectra. The resulting DSSCs exhibited stepwise performance improvement: CNT–ZnO (η = 5.55

In the present work, a member of the Aurivillius family, Bi4Ti3O12 (BTO), was synthesized and comprehensively characterized for its structural, morphological, dielectric, ferroelectric, and pyroelectric properties. XRD analysis confirmed the formation of a single-phase Aurivillius-type bismuth layered- perovskite structure with an orthorhombic crystal system (space group B2cb) with refined lattice parameters a ≈ 5.45 Å, b ≈ 5.41 Å, and c ≈ 32.83 Å. Rietveld refinement showed high structural integrity, while the analysis of TiO6 octahedra evidenced the local distortion responsible for spontaneous polarization. Scanning electron microscopy (SEM) images showed uniformly distributed grains ( 2.6 µm); energy dispersive X-ray (EDX) with elemental mapping further confirmed compositional homogeneity. XPS spectra confirmed the oxidation states of Bi3+ and Ti4+, further validating phase purity and intense chemical ordering. Dielectric measurements in a broad temperature range from 200 °C to 700 °C displayed a sharp anomaly at 650 °C corresponding to the Curie temperature, representing a transition from the ferroelectric to the paraelectric phase. Ferroelectric P–E hysteresis loops showed a remnant polarization of up to 52 µC/cm2 and a clear domain switching at fields up to 230 kV/cm. Importantly, the pyroelectric coefficient showed an enhancement in the range from 1.42 × 10–4 to 16.28 × 10–4 C m⁻2 K⁻1 accompanying the leakage current reduction. The calculated figures of merit (Fi = 15.54 × 10–10 mV−1, Fv = 11.53 × 10–2 m2•C−1, Fd = 39.83 µPa−1/2) evidence the promising potential of the material in lead-free pyroelectric devices. The sensor based on Bi4Ti3O12, under identical measuring conditions, provided a respectable output of ≈1.8 V, thus ranking this material as one of the best candidates in eco-friendly pyroelectric and energy-harvesting applications.

This study investigates the tribological behaviour of friction stir processed (FSPed) AA8011 surface composites reinforced with 1–3 wt