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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.

Aims. To evaluate scope of diagnosing tools-Alvarado score, CRP, USG, and CT in acute appendicitis. Method. Conducted observational study of 152 patients in Department of Emergency Medicine, Sri Ramachandra Medical College and Research Institute, Chennai, India between January to December 2022. The diagnostic tool’s (Alvarado score, CRP, USG, CT (abdomen), sensitivity, specificity, accuracy, and ROC were analyzed to diagnose acute appendicitis. Results. Among 152 study patients, males - 86, females - 66, higher number of age group was 7-61.2%) (0.0271), CRP - identified 95.1% (

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.

Biochar is a promising solution in the competent removal of such toxicants due to its cost-effectiveness, natural properties, biologically rich composition, and environment-friendly characteristics. All the possible heavy metals found in industrial effluents and how to treat them with biochar-based adsorption strategies to lead to a cleaner hydrosphere system were analyzed. Biochar interactions in heavy metal adsorption are studied and profiled to a small extent to allow regional knowledge of how these interactions occur and how biochar studies are taking place. Industrial effluents possess various toxic pollutants that extend their exposure to all kinds of living organisms, contaminating and degrading the biosphere. Adsorption helps mitigate difficulties such as wastewater treatment, remediation studies, and hazardous waste management, providing a sustainable and quality life. The characteristics of biochar produced through pyrolysis using different biomasses analyzed are carbon 35–90 wt%, surface area 5–2100 m2/g, and total pore volume 0.001–50 cm3/g at the temperature range of 400°C–750ºC. The optimum conditions required for maximum adsorption efficiency (96%–99%) of heavy metals majorly lie under the range of temperature 30°C–60°C, pH 5–8, and time 30 min to 1 h. The outcome of this review has significant results on remediation techniques, highlighting biochar’s potential as a flexible tool and as an adsorbent in addressing the challenges related to the possible threats implied by heavy metal contamination in industrial effluents.

Canals are a very imperative source of irrigation for the agricultural sector in India. Seepage causes major water loss in canals, and hence, the installation of liners becomes necessary. Compacted clay soils are commonly used as liners in the canals. This structure will most probably be subjected to salinization and desalinization cycles throughout its life. Because of the interaction between the pore liquid and clay particles, physico-chemical influences considerably impact the behavior of clay barriers. In this paper, the effect of interacting fluid on volume change, consolidation parameters, and hydraulic conductivity of compacted clay soil is investigated with the help of a one-dimensional consolidation test. The compacted clay specimens were immersed alternatively with distilled water (DW) and sodium chloride (NaCl) solutions (SW) at constant loading of 10 kPa, which replicates the load conditions in the field canal due to 1 m head of water and incremental loading as per IS 2720 part 15 standards. The experimental results proved that there is a percentage volume change increase of about two times for each stage inundated with 4M NaCl solution than its preceding stages inundated with distilled water at constant loading of 10 kPa. The consolidation rate was accelerated with 4M NaCl solution than the normal consolidation at incremental loading. The permeability coefficient in the salt water-induced sample increased by 217% more than the distilled water-induced sample at incremental loading. Therefore, the soil specimen subjected to alternate salinization and desalinization cycles significantly affects the volumetric and consolidation behavior, leading to decreased life of clay barrier structures.

Polymer-based soil stabilization has fascinated substantial interest in the field of research intending to gain a better knowledge of the anticipated soil characteristics after polymer treatment. Intricate research on the engineering performance of expansive soil which is highly challenging due to its swell and shrink nature based on variations in water regime, treated with guar gum, a biopolymer made from gum along with polyethylene terephthalate fibre, one of the most generated plastics, resulting in massive waste, is accomplished through this entire experimental investigation. Comprehensive geotechnical tests and microstructural examinations have been performed to optimize the guar gum for enhancement of soil properties and to comprehend the interactive mechanism with the soil. The biopolymer at dosages 0.5%, 1%, 1.5%, and 2% was added to the soil. Polyethylene terephthalate Fibre with an aspect ratio of 28 is used with the soil at an increment of 0.4% up to 1.6%. The optimum dosage of biopolymer was mixed with polyethylene terephthalate fibres, and its effect on geotechnical properties was carried out separately. From the experimental investigations, it is comprehended that there is a reduction of 27% and 40% in plasticity index and swelling, respectively, at an optimum dosage of 0.5% GG when compared to untreated soil. Furthermore, there is a marginal decrease of 24% in dry density, 310% increase in CBR value, and 33% reduction in compressibility of the soil treated with 0.5% GG with 1.6% PET fibre, when compared to virgin soil. The present study was conducted to improve the subgrade soil strength beneath the pavements. The usage of biopolymer and its combination with polyethylene terephthalate fibres shows that there is a considerable improvement in modifying the geotechnical properties, and its coupling effect contributes to higher California bearing ratio values. According to the outcomes of this investigation, it is proven that biopolymer and polyethylene terephthalate fibre is definitely an alternate to conventional materials. The present study was conducted to improve the subgrade soil strength beneath the pavements.

Nowadays the automotive industry mostly prefers innovative solid-state welding technologies that would enable to welding of lightweight and high-performance materials. In this work, 3105-H18 Aluminium alloy (Al) and pure Copper (Cu) specimens with 0.5 mm thickness have been ultrasonically welded in a dissimilar (Al-Cu) manner. Optimization of process parameters of ultrasonic welding has been carried out through full factorial method, three levels of variables considered for this experimental studies namely, weld pressure, amplitude, and time, also each variable interaction with welding strength has been studied. Additionally, micro-hardness and microstructure investigation in welded joints has been studied. The result shows that the weld strength greatly influenced weld amplitude at a medium and higher level of weld pressure. The interface micro-hardness of the welded joint has lower compared to the base metal.

Nano-alumina-doped catechol formaldehyde polymeric composite was prepared, characterized, and applied as an adsorbent for the removal of an anionic dye Congo red (CR) and a cationic dye SafraninO (SF), by adsorption process especially from aqueous solutions. Characterizations such as particle size distribution, zeta potential, BET, FTIR, and FESEM-EDAX were carried out for the adsorbent prepared. All experiments were conducted at the batch condition to study the effects of initial dye concentration (CR: 30–90 mg/L and SF: 10–50 mg/L), pH (2–11), temperature (25–55°C), and adsorbent dosage (0.05–0.3 g) on dye removal. The isotherm models (Langmuir, Freundlich, and Temkin) were analyzed for this adsorption work. The kinetic data obtained were analyzed by the pseudo-first-order, pseudo-second-order, Bangham, and Chien–Clayton equations. Dyes adsorption data were well fitted with the Freundlich isotherm equilibrium model and the pseudo-second-order kinetic model. Study results suggested that the nano-alumina-polymeric composite could be an effective adsorbent for anionic dye rather than cationic dye.

It is essential to understand the weld interface characteristics and mechanical properties of dissimilar joints to improve its quality. This study is aimed at exploring the properties of friction welded magnesium–titanium dissimilar joint using tensile testing coupled with digital image correlation, optical and scanning electron microscopy, x-ray diffraction and microhardness measurements. Microstructurally different regions such as contact zone, dynamic recrystallized zone, thermo-mechanically affected zone, and partially deformed zone in the magnesium side were observed. No discernible regions were observed in the titanium side, as it had not undergone any significant plastic deformation. Phase analysis indicated that the aluminium from the magnesium side diffused toward the weld interface and formed a thin continuous intermetallic layer by reacting with the titanium. Microhardness mapping showed a steep hardness gradient from the titanium to magnesium side. Critical analysis is done on the tensile characteristics of the specimen and the response of the local regions to the deformation process is mapped.

In creep conditions, conventionally, C* and C(t) line integrals are used for characterising the crack tip. However, the true crack driving force or its rate cannot be described by any of the conventional parameters. The theoretical validity of conventional crack tip-characterising parameters like J or Ct is also restricted, making it hard to anticipate the driving forces underlying cracks. To investigate the creep crack growth behaviour of this material an experimental analysis of SS316LN at 650 °C is performed. The crack extension is modelled through the node-release technique, and a configurational force-based rate of change of J integral is calculated by post-processing of the finite element results. The results show that the Ct and dJepc/dt calculated from FE analyses are similar and the trend is also similar to the experimentally measured C*-values. [ABSTRACT FROM AUTHOR]