Raidighi College

Precipitation hardening in Mg-Al alloys mainly comes due to the interaction and competition between basal dislocations and Mg17Al12 precipitates. The precipitation hardening of Mg-alloys is considerably less effective compared to other metallic alloys, such as aluminum, a phenomenon attributed to geometric effects. Specifically, the Mg17Al12 precipitates tend to grow in thin plate-like or lozenge-shaped forms, or as elongated rods, all of which are aligned parallel to the basal plane. Nonetheless, there is a paucity of detailed atomistic simulations investigating the dislocation–precipitate interactions, particularly in the zero-temperature limit, to comprehensively assess the strengthening potential of these precipitates. This study focuses on the interaction between screw-type basal dislocations and precipitates in the athermal limit, employing molecular statics. Specifically, the critical resolved shear stress (CRSS) required to bypass the precipitates is elucidated as a function of precipitate size and juxtaposed with the predictions of classical continuum models. A detailed study to understand the role of precipitate orientation, dislocation offset from the precipitate, and multiple cutting mechanism are carried out in this paper. Atomistic microstructures reveal the shearing plane and shearing mechanism while the dislocations bypass the precipitate. These findings offer crucial insights into the precipitate hardening mechanisms and propose novel avenues for enhancing the mechanical properties of Mg-Al alloys.

Potato cultivation in West Bengal is usually concentrated in sandy loam and other well-drained soils and is commonly supported by substantial synthetic fertilizer inputs. The present study, conducted between 2021 and 2026, evaluates an alternative production model in the East Kolkata Wetlands, where potato was cultivated on silty clay soil under zero tillage with approximately 11-inch paddy straw mulching and irrigation from a sewage-fed canal. Soil test records, canal-water nutrient analysis, field yield records, and paired temperature measurements from the bed surface and tuber zone have been examined in this study. Across four soil reports, mean values are pH 5.62, organic carbon 0.72%, available nitrogen 437.38 kg/ha, available phosphorus 37.64 kg/ha, and available potassium 456.97 kg/ha. Canal water contained 17.1 mg/L dissolved nitrogen as NH3-N, 1.95 mg/L dissolved phosphorus as PO4-P, and 4.82 mg/L dissolved potassium; at an assumed seasonal irrigation volume of 6,000 m3/ha, this corresponds to approximately 102.6 kg N/ha, 11.7 kg P/ha, and 28.9 kg K/ha. Potato productivity under the East Kolkata Wetland silty clay system ranged from 21,525 to 25,830 kg/ha, with a mean of 23,677.5 kg/ha, representing 77.7% to 93.2% of the comparative benchmark yield of 27,720 kg/ha reported for conventional fertilizer-dependent sandy loam potato farming in other parts of West Bengal. Temperature observations showed that the thick straw mulch reduced tuber-zone temperature by an average of 9.25°C relative to the aerial bed temperature, and this paired difference was statistically significant (paired t-test, p = .033). Although the small number of yield observations limits formal inference, the results indicate that wastewater irrigation, native soil fertility, and thick paddy straw mulch jointly created a productive potato-growing environment in a soil type that was usually considered less suitable for the crop. The system appears particularly strong in reducing synthetic nitrogen requirement, while phosphorus management remains necessary for balanced crop nutrition in conventional farming so in the zero-tillage model, with the creation of favourable environment of beneficiary microbes the Pseudomonas fluorescens 10 8 /gm and Trichoderma viride 10 7 /gm are used as Biocontrol and Phosphorus uptake enhancer.

The severe contamination of water resources with toxic, carcinogenic, and non-biodegradable organic dyes poses serious threats to human health and aquatic ecosystems. Rhodamine B (RhB) and Methylene Blue (MB), are of particular concern due to their persistence, high toxicity, and tendency to accumulate in the environment. Therefore, developing cost-effective and sustainable methods for the detection and removal of such pollutants is of great importance. In this context, we synthesized Fe3O4@NGQDs nanocomposites using a simple co-precipitation method. The hybrid material was thoroughly characterized by FTIR, XRD, SEM, and TEM, confirming its structural integrity and successful incorporation of Fe3O4 with nitrogen-doped graphene quantum dots (NGQDs). The FG nanocomposite exhibited fluorescence-based sensing performance toward RhB and MB in aqueous media, enabling highly sensitive detection. Additionally, the material displayed photocatalytic activity under visible light irradiation in presence of H2O2, resulting in efficient degradation of both dye pollutants. The dual sensing and photocatalytic properties of Fe3O4@NGQDs highlight its potential as a multifunctional material and offer a promising pathway for the remediation of hazardous organic contaminants.

Imidazoles have a unique position in heterocyclic chemistry as these constitute the basic framework of several bio-molecules. Thus, increasing research is being carried out on the synthesis of imidazoles and their derivatives, mainly because of the application of imidazoles in pharmaceutical and medicinal research. Keeping sustainability in mind, researchers are developing synthetic pathways for the synthesis of imidazoles and their derivatives by employing techniques involving green tools, thus leading to sustainable pathways. In this review, we aim to compile such synthetic methodologies involving green tools for the synthesis of imidazoles. The review will cover the synthetic reactions that involve green tools such as microwave irradiation, ultrasound irradiation, and ball milling. We aim to highlight the scope and relevance of such green tools in today’s synthetic research. Through this review, we wish to contribute towards the synthesis of imidazoles that serve as a useful class of heterocyclic compounds involved in the development of pharmaceutically active molecules. We sincerely hope that this review will serve as a relevant guide for future sustainable research in the synthesis of imidazoles and their derivatives.

The genus Plumbago (family Plumbaginaceae), commonly known as leadwort, is a sub-tropical shrub that produces secondary metabolite plumbagin, which is employed by pharmaceutical companies and in clinical research. Plumbagin is a potent pharmaceutical because of its anti-microbial, anti-malarial, antifungal, anti-inflammatory, anti-carcinogenic, anti-fertility, anti-plasmodium, antioxidant, anti-diabetic, and other effects. This review documents the biotechnological innovations used to produce plumbagin. The use of modern biotechnological techniques can lead to a variety of benefits, including better yield, increased extraction efficiency, mass production of plantlets, genetic stability, increased biomass, and more. Large-scale in vitro propagation is necessary to minimize over-exploitation of the natural population and allow the use of various biotechnological techniques to improve the plant species and secondary metabolite production. During in vitro culture, optimum conditions are requisites for explant inoculation and plant regeneration. In this review, we provide information on various aspects of plumbagin, depicting its structure, biosynthesis, and biotechnological aspects (both conventional and advanced) along with the future prospects. KEY POINTS: • Critical assessment on in vitro biotechnology in Plumbago species • In vitro propagation of Plumbago and elicitation of plumbagin • Biosynthesis and sustainable production of plumbagin.