Anna University is a public state university located in Tamil Nadu, India. The main campus is in Chennai. It was originally established on 4 September 1978 and after taking many different forms over the years, as per a September 2020 bill passed in the Tamil Nadu Legislative assembly, the varsity is now reconstituted to be an affiliating university for engineering colleges across Tamil Nadu excluding the engineering colleges that are part of the premier Anna Technological and Research University. The University is now the affiliating authority for close to 550 engineering colleges in Tamil Nadu.
The development of aluminum-air batteries provide a promising solution for stabilizing intermittent renewable energy sources, such as solar and wind. A significant challenge to their large-scale deployment is the stability on aluminum electrodes in the electrolyte, which presents both economic and corrosion-related challenges. Issues related to corrosion, cost and electrode thinning compromises the performance of aluminum electrodes. Nonetheless, aluminum alloys are emerging as a compelling alternative for aluminium electrodes due to their high electrochemical activity and ease of processing. Herein, an integrated framework that combines Pourbaix diagrams (PD) with finite element modeling (FEM) is proposed to systematically investigate the stability of aluminum-based electrode materials. Within this framework, PD predict the stability regions of key electro active species of aluminum and its alloys, such as Al (OH)3, AlO2-and Al (OH)4-, under various pH, concentration and temperature. PD offer a comprehensive assessment of material behavior in corrosive environments. A FEM model incorporated in the framework illustrates thinning of the electrode-electrolyte interface due to electrode corrosion. The model predictions are validated against experimental data in an inbuilt cell, showing good agreement in electrode thickness reduction and corrosion rate predictions under acidic conditions. The model shows that pure Al obtained a pit with a depth of 1.31 mm at overpotential of 1.93 V, while Al 7075 eroded into a 1.9 mm pit at 1.87 V, thus having a larger corroded area. These findings provide a foundation for screening aluminum-based electrodes based on corrosion rates and thermodynamics parameters for batteries used in energy storage systems.
Effective use of by-products is a very efficient method for improving sustainability and efficiently handling and disposing of agricultural waste produced in the fruits and vegetable processing industries. These by-products could be of commercial value if they are used in the right technical applications. In this context, we utilize 1%, 2%, and 3 wt% of turmeric residue-extracted curcumin (TE-CUR), derived from biomass waste, incorporated into polylactic acid (PLA)/polycaprolactone (PCL) blend was prepared by solution casting method to detect observable pH color changes that indicate food deterioration. All prepared PLA/PCL blends were evaluated for packaging performance. SEM, FTIR, and XRD analyses indicated effective miscibility and uniform distribution of TE-CUR in the blends. TGA results demonstrated enhanced thermal stability with TE-CUR addition. Mechanical testing revealed that the blend with 3% TE-CUR displayed maximum flexibility, achieving an elongation at break of 13.05%, over twice that of pure PLA (7.2%). Additionally, water vapor and oxygen permeability tests confirmed that TE-CUR improved the barrier properties of the PLA/PCL blends. The antimicrobial test and DPPH assay used to investigate TE-CUR extract in ethanol clearly demonstrated that the film samples have a strong antimicrobial activity and antioxidant impact due to the tunable release of TE-CUR. The PLA/PCL/TE-CUR blended film was assessed for its ability to prolong the shelf life of fresh cut apples at 4°C, revealing a significant color change indicative of deterioration of fruits. The findings suggest that this novel biodegradable blend could serve as an effective, cost-efficient smart indicator for active food packaging.
Corrosion is an inevitable physicochemical phenomenon that, although it cannot be eliminated, can be significantly retarded through appropriate mitigation strategies. From an industrial standpoint, corrosion represents a substantial economic burden, contributing no direct value to production while imposing additional maintenance, operational, and replacement costs. Conventional corrosion prevention and protection methods are often expensive and frequently associated with environmental hazards, necessitating the exploration of more sustainable alternatives. The ideal corrosion mitigation approach should be cost-effective, operationally simple, technically feasible, and, most importantly, environmentally benign. In this context, green corrosion inhibitors have emerged as a promising class of materials, generally offering an effective, low-cost, and eco-friendly solution with minimal environmental footprint. Their rising industrial relevance has spurred extensive research activity focused on their development, optimization, and application. Green corrosion inhibitors encompass a broad spectrum of substances, both traditional and recently developed. Conventional green inhibitors include plant extracts, essential oils, biomolecules, expired pharmaceuticals, rare-earth metal complexes, ionic liquids, and amino acids along with their derivatives. In contrast, modern innovations in this domain have led to the development of advanced green inhibitors such as volatile corrosion inhibitors, nanocomposite-based systems, metal–organic frameworks (MOFs), deep eutectic solvents (DESs) and MXene. These novel materials generally exhibit enhanced corrosion inhibition efficiency and align with principles of green chemistry and sustainable engineering. This chapter provides a comprehensive overview of various categories of green corrosion inhibitors, highlighting key examples and their mechanisms of action. Emphasis is placed on both well-established and emerging systems, underscoring their potential to revolutionize corrosion mitigation in an environmentally sustainable manner.
Metal ferrites have been widely explored for supercapacitor applications due to their structural stability, several redox states, and remarkable pseudocapacitive behavior. In this study, the solution combustion technique has been employed to synthesize a SrFe2O4/NiFe2O4 (SFO/NFO) nanocomposite to observe the electrochemical characteristics. Morphological and structural investigations, such as XRD, FTIR, FESEM, TEM, BET, and XPS, revealed the effective formation of a nanocomposite with distinguished phases. SFO/NFO revealed an enhanced specific capacitance of 810 F g−1 (1296 mF cm−2) at a current density of 1 A g−1 and 1052 F g−1 (1683 mF cm−2) at a scan rate of 1 mV s−1 with low charge transfer resistance, signifying fast electron transport and quick ion diffusion. The practical applicability has been established by the fabrication of a symmetric supercapacitor device using the SFO/NFO electrode, which illuminated a red LED bulb for 1 min. The mutual interaction between SFO and NFO renders an effective option for the as-synthesized nanocomposite to be used as a promising electrode for supercapacitor applications.
This study evaluated ten inland wetlands in Tamil Nadu, India during May–July 2025 using a depth-integrated, multi-matrix (water–sediment-soil) assessment framework combining physico-chemical characterization, ecological risk indices and multivariate statistical modelling to identify dominant pollution stressors and inform sustainable wetland management. Water, sediment and soil samples were analysed following APHA (2017) standard methods. The integrated framework incorporated contamination factor, pollution load index, potential ecological risk index, geo-accumulation index, contamination degree, Pearson correlation, Kaiser–Meyer–Olkin test, Bartlett’s test of sphericity and Principal Component Analysis (PCA) to quantify contamination status, evaluate ecological risk and enable cross-matrix source apportionment. Surface waters exhibited neutral to mildly brackish conditions. Severe oxygen depletion (DO: 0.1–4.0 mg/L), accompanied by elevated biological oxygen demand (0.17–4.5 mg/L) and chemical oxygen demand (43.2–420.2 mg/L), indicated organic loading and ecological stress. Dissolved nutrient concentrations were generally within Tamil Nadu Pollution Control Board guideline limits (TN: 0.1–6.34 mg/L; TP: 0.09–0.45 mg/L). In contrast, sediments and soils functioned as substantial nutrient reservoirs, with TN and TP reaching 5,387 and 32.5 mg/kg, respectively, reflecting long-term accumulation and legacy loading and underscoring the dominance of internal nutrient cycling. Metal concentrations in water were below detection limits, indicating minimal toxicological risk. Multivariate analysis demonstrated strong coupling among water, sediment and soil variables, particularly among EC, salinity, total dissolved solids, soil organic carbon, TN and TP. PCA indicated that most metals were predominantly lithogenic in origin, whereas Cd behaved as a distinct anthropogenic tracer across matrices. Ecological risk indices revealed generally low to moderate contamination, with localized hotspots. The results delineate a functional continuum in which surface waters act as transport pathways, sediments serve as geochemical sinks and soils integrate cumulative anthropogenic inputs. Internal nutrient cycling and organic matter accumulation emerged as the principal ecological stressors, while metal-related risks remained spatially limited. These findings emphasize the need for nutrient-focused, site-specific management and provide risk-informed evidence to support adaptive strategies for enhancing the long-term resilience of Tamil Nadu’s inland wetlands.
