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In this study, the influence of Al-doping concentration on the thermal and rheological characteristics of pristine zinc oxide (ZnO) nanofluids was investigated across a range of temperatures and nanoparticle concentrations. A multilayer perceptron (MLP) artificial neural network (ANN) with an optimized topology was employed to model the thermal conductivity and viscosity of nanofluids. The addition of 0.13 M of Al-doped zinc oxide nanoparticles at 1 % rate led to a remarkable 64 % increase in the thermal conductivity of the base fluid (50:50 ratio water + ethylene glycol mixture). Furthermore, incorporating 1 % of these Al-doped nanoparticles outperformed pure zinc oxide, resulting in a 44 % boost in thermal conductivity. The enhanced heat transfer capabilities of Al-doped zinc oxide were evident across different doping and nanoparticle concentrations. The viscosity of nanofluids increases with an increase in nanoparticle concentration and decreases with an increase in temperature. ZnO and Al-doped ZnO nanoparticles have been prepared and studied their structural, morphological and elemental properties using XRD, SEM and EDS respectively. The predicted thermal and rheological behaviours are in close agreement with the experimental values.

Irradiation-induced defects and the precipitates in the wrapper material of the Indian Fast Breeder Test Reactor (FBTR), SS 316 are analyzed using the synchrotron source-based Angle Dispersive X-Ray Diffraction (ADXRD) technique with X-rays of energy 17.185 keV (wavelength ∼0.72146 Å). The differences and similarities in the high displacement damage samples as a function of dpa (displacement per atom) and dpa rate in the range of 2.9 × 10−7- 9 × 10−7 dpa/s are studied. Ferrite and M23C6 are commonly observed in the present set of high displacement damage 40–74 dpa SS 316 samples irradiated at temperatures in the range of 400–483 °C. Also, the dislocation density has increased as a function of the irradiation dose. The X-ray diffraction peak profile parameters quantified such as peak shift and asymmetry show that the irradiation-induced defects are sensitive to the dpa rate-irradiation temperature combinations. The increase in yield strength as a function of displacement damage is also correlated to the dislocation density.

Organic solid waste loading emerges as a serious environmental threat. Vermicomposting and composting are the two biological processes having the potential to effectively treat organic waste. In composting, in a controlled environment, microorganisms are used to treat organic wastes. Vermicomposting is a low-cost waste management technique incorporates earthworms and microorganisms to produce highly nutritive vermicompost, which in turn preserves the ecosystem. In vermicomposting, earthworms are the important players, the rate of mineralization is increased and nutritive cast is produced as a byproduct. Vermicompost improves soil aeration, microbial population, soil enzyme activity, and texture while also fostering plant growth. Crop growth and yield are greatly impacted by vermicompost. Vermicast ensures sustainable agricultural practices in addition to improve soil health and plant growth. Adsorption, precipitation, redox reactions, and complexation all work together to make heavy metals unavailable during composting. Heavy metals like mercury, cadmium, lead, copper, zinc, and manganese are bioaccumulated by earthworms. When persistent organic pollutants are composted, microbes take them up and reduce their bioavailability. Through vermicast, earthworms convert microplastics into nanoplastics. This review discusses developments in composting and vermicomposting of organic wastes, the potential contribution of earthworms, presence of heavy metals in organic waste, the influence of biochar on composting and removal of toxic pollutants through composting and vermicomposting.

This paper presents the optimized surface morphology to enhance transferred charge between the mental and dielectric of the modelled triboelectric nanogenerator. The structured shape of the dielectric layer is a vital factor in enhancing the output performance of the triboelectric nanogenerator. In this study, flat, cone, circular and rectangular shapes are structured on the dielectric surface of TENG. Its output performance is examined by conducting a numerical study on the finite element method in COMSOL Multiphysics software. Among the above stated structured surface TENGs, the structured rectangular surface triboelectric nanogenerator produces an improved output open-circuit voltage of 26 V for an externally given 3K Pascal pulse pressure as input. Hence, the result indicates that the structured surface TENGs can make a portable self-powered healthcare device such as heart rate, respiratory rate, and blood pressure measurement.

Navigation satellite system plays a major role in finding the position of a user. Similar to GPS, Navigation with Indian Constellation (NavIC) is developed by India to cater the country needs. The NavIC Standard Positioning Service User Receiver (UR) placed at ACS College of Engineering (12.8914° N, 77.4657° E), Bangalore for field trial and data collection. The accuracy of the navigation system is influenced by several kinds of error factors, among which the signal delay influenced by the ionosphere is the greatest error factor. The delay in signal causes error in satellite signal range data and it is called range error. This range error can reduce the accuracy of user position. Hence estimation of range error is very essential. In order to give the appropriate user position, estimation of Total Electron Content (TEC) is vital, which indicates ionospheric error (signal delay). In this paper, VTEC of ionosphere is estimated for the entire day and over a month. The observation data required for estimation of TEC is collected from NavIC SPS receiver located at ACS College of Engineering Station (ACSCES), Bangalore. By using estimated VTEC value, it is possible to correct range error which results in accurate position estimation. NavIC TEC derived using pseudo range at ACSCES is compared with GPS TEC and IRI-2016 TEC which belongs to IISC Station. From the comparison, it is observed that, the maximum NavIC TEC is 43.0552 TECU and maximum GPS TEC is 44.6131 TECU and maximum IRI-2016 TEC is 18.6 TECU. RMSE between GPS and NavIC TEC is 5.486 TECU, correlation coefficient is 0.9748 and average difference is 5.2306 TECU. Similarly, RMSE between NavIC and IRI-2016 TEC is 9.9899 TECU, correlation coefficient is 0.93 and average difference is 9.421 TECU. From the collected data, C/No are plotted for each satellite. From the C/No plots, it is observed that, C/No is good i.e. above 40 dB-Hz. Based on the results, it is evident that, NavIC is suitable for navigational applications in Indian region.

Evolving Anthropocene epoch wields significant influence in altering atmospheric carbon, which affects the carbon cycle, leading to climate change. Understanding the carbon stock, fate, and transport across ecosystems are essential in determining India's carbon budget, hitherto, unavailable. In this study, we have analysed the stock, source, distribution, flux, and the relationship between terrestrial and aquatic black carbon over a high-altitude mountainous area in the Western Ghats region using the data collected from September 2019 to February 2021. Soil Organic Carbon (SOC) and Black Carbon (BC) are the highest in the forest region (SOC:23 ± 3 g of C/kg (dry weight (dw)), BC:6 ± 3 g/kg) and are the lowest in the urban region (SOC: 13 ± 2 g of C/kg (dw), BC:2 ± 1 g/kg). SOC is labile, whereas BC is non-labile. The BC/SOC ratio represents soil carbon lability. Topsoil BC/SOC ratios vary by land use and land cover, with urban areas having greater labile carbon pools than the forests. Dissolved BC (DBC) concentrations were most strongly correlated with bulk Dissolved Organic Carbon (DOC) concentrations in midstream (R = 0.6, p < 0.05), headwater streams (R = 0.3, p < 0.05) and to the soil bulk DBC (R = 0.3, p < 0.05), indicating the presence of transfer mechanism of soil to streams. The molecular associations revealed the presence of biolabile autochthonous compounds suggesting the crucial role land use and land cover play on watersheds. A positive relationship between DOC with seasonal hydrology and gradient significantly influences the DBC flux across regional streams. Intercomparison of observed terrestrial and aquatic carbon stocks with globally modelled data indicates an overestimation of regional-scale stock. These new findings have repercussions to policy framework on regional climate change. Further, the results suggest that a consistent quantification of BC and integration of regional, and global source-to-sink process are needed in order to understand and better quantify biogeochemical process cycles and associated climatic impacts., (Copyright © 2022 Elsevier B.V. All rights reserved.)