http://ore.immt.res.in:80 The ORE digital repository system captures, stores, indexes, preserves, and distributes digital research material. 2026-09-08T16:02:24Z http://ore.immt.res.in/handle/2018/4021 Oxygen vacancy-engineered interfacial bonding for DNA conjugation on nanopatterned rutile TiO2: experimental and in silico study Mishra, I.; Chitara, R.; Majumder, S.; Joshi, S. R.; Subudhi, U.; Gajjar, P. N.; Gupta, S. K.; Varma, S. Bioconjugation of nucleotides with oxide surfaces forms the fundamental basis for numerous biotechnological applications. Here, we investigate the role of nanopatterned rutile TiO2 surfaces, with particular emphasis on oxygen vacancy states among the irradiation-induced surface modifications, generated during ion-beam-induced nanopatterning, in DNA adsorption. The formation of possible Ti-O-N related interfacial configuration together with the associated charge-transfer characteristics suggests that irradiation-induced surface modifications, including oxygen-vacancy states and other defects, contribute to the observed interfacial electronic behaviour. In the absence of nanopatterning, such irradiation-induced defect states are not observed, and DNA adsorption appears to occur predominantly through Ti-N-related interactions. Experimental findings are corroborated by density functional theory (DFT) calculations focused on adenine adsorption on TiO2. The results reveal electron transfer from the surface to the adenine molecule, directly influencing local interfacial electronic interactions. DFT results indicate that while pristine TiO2 sites govern adsorption stability, oxygen-vacancy states are associated with enhanced interfacial charge transfer, thereby modulating the electronic characteristics of the adenine-TiO2 interface. The implications of these electronic effects for DNA immobilization efficiency and functional performance remain beyond the scope of the present study. 2026-01-01T00:00:00Z http://ore.immt.res.in/handle/2018/4020 Hydrometallurgical treatment of an indigenous bismutite ore: process optimization and kinetics analysis Balogun, A. F.; Baba, A. A.; Tripathy, B. C. Bismuth (Bi) has gained increasing attention as a potential substitute for lead (Pb) in consumer and industrial applica-tions owing to its comparatively benign environmental and health characteristics. In this study, the leaching behaviour of bismuth from bismutite ore was investigated using nitric acid, a commonly employed lixiviant in hydrometallurgical pro-cessing. The ore sample contained 78.56 wt% Bi, along with Si (11.51 wt%), Al (3.68 wt%), and Fe (1.20 wt%), and was primarily composed of bismutite, zinnwaldite, and quartz. Leaching experiments were conducted in a 1000 mL double-jacketed glass reactor equipped with a reflux condenser, mechanical stirrer, and temperature control system. The effects of nitric acid concentration, reaction temperature, and particle size on bismuth dissolution were systematically examined. Under optimized conditions (3.0 mol/L HNO3, 80 degrees C, particle size of 45 mu m, and 120 min), a maximum bismuth leaching efficiency of 91.60% was achieved. X-ray diffraction analysis of the leach residue identified quartz and sapphirine as the predominant undissolved phases. Kinetic evaluation indicated that the dissolution process followed the external liquid-film mass transfer control model, with a reaction order of 0.79 and an apparent activation energy of 15.77 kJ/mol. Thermo-dynamic and kinetic assessments were conducted to determine the feasibility of dissolution. The calculated changes in enthalpy (Delta H) and Gibbs free energy (Delta G) confirmed that Bi(III) recovery is endothermic and spontaneous within the temperature range of 301 to 353 K. The leach residue obtained under optimal conditions can be further processed as a potential SiO2 source for paint production. 2026-01-01T00:00:00Z http://ore.immt.res.in/handle/2018/4019 Interactive physiological responses of Vigna radiata L. under combined heat stress and radiofrequency radiation Panda, D. K.; Das, D. P.; Behera, S. K.; Dhal, N. K. Plants are increasingly exposed to multiple co-occurring environmental stressors, yet their combined effects remain insufficiently understood. In the present study, the interactive effects of heat stress (42 degrees C) and radiofrequency (RF) radiation (2.6 GHz) were investigated in Vigna radiata L. seedlings, focusing on growth, stem anatomy, stomatal characteristics, and biochemical responses under controlled conditions. Heat stress significantly reduced plant height by up to 56.3% at day 15, while RF radiation alone caused a moderate reduction (similar to 20%). Under combined stress, plant height decreased by 58.8%, closely resembling heat stress alone, indicating a predominantly heat-driven, non-additive interaction. Microscopic analysis revealed progressive structural damage, with combined stress causing noticeable epidermal disruption and poorly differentiated xylem elements compared to individual treatments. Stomatal behaviour was also largely governed by heat stress, with stomatal pore area decreasing from 28.87 mu m(2) (control) to 19.98 mu m(2) under heat and 17.54 mu m(2) under combined stress, whereas RF-treated plants showed increased pore opening (56.34 mu m(2)). In contrast, biochemical parameters showed the strongest response to combined stress. Relative water content declined from 88% (control) to 65% (heat) and 52% (combined). Similarly, carbohydrate and protein contents decreased markedly under combined stress (16.2 and 10.4 mg g(-1), respectively) compared to control (32.5 and 18.6 mg g(-1)). Chlorophyll content showed moderate reductions primarily driven by heat stress. Overall, the findings demonstrate parameter-specific responses characterized by heat-dominated structural effects and cumulative metabolic impairment under combined stress, providing new insights into RF-plant interactions under multi-stress conditions. 2026-01-01T00:00:00Z http://ore.immt.res.in/handle/2018/4013 A MultifunctionalMoS/g-CN 2D Heterointerfacefor Solar-Driven Ciprofloxacin Degradation,Oxygen Reduction, Oxygen Evolution Electrocatalysis, and FluorescentGlyphosate Sensing Sahu, P. K.; Rath, A.; Sahoo, S.; Sharma, P.; Baral, A. K.; Siddiqui, K. A.; Nanda, A.; Tripathy, B. C.; Pradhan, A.; Naik, B. Developing multifunctional heterostructures capable of integrating environmental remediation, solar-to-chemical conversion, electrocatalysis, and chemical sensing within a unified material platform remains a major challenge due to the lack of a common structure-property relationship governing these diverse functionalities. Herein, a 2D/2D MoS2/g-C3N5 heterostructure was rationally engineered via a facile ultrasonic-assisted assembly strategy to construct an electronically coupled heterointerface with accelerated interfacial charge transfer kinetics. Structural, morphological, optical, and electrochemical investigations collectively confirm the intimate integration of MoS2 nanosheets with the g-C3N5 framework, resulting in enhanced visible light absorption, suppressed charge recombination, directional migration, and surface electronic modulation. Importantly, these interfacial electronic features serve as the common mechanistic origin for observed multifunctional behavior. The optimized MC31 (MoS2/g-C3N5 = 3:1) heterostructure exhibits superior solar-light-driven ciprofloxacin (CIP) degradation, predominantly mediated by superoxide (center dot O2 -) radicals, along with enhanced photocatalytic H2O2 generation. The same charge-separation characteristics further promote efficient oxygen evolution electrocatalysis by facilitating rapid interfacial electron transport and favorable surface reaction kinetics. In parallel, the electronically modulated heterointerface enables sensitive fluorescence-based glyphosate sensing through effective charge-transfer-induced fluorescence quenching. Mechanistic investigations suggest that the enhanced multifunctional performance originates from a direct Z-scheme charge transfer pathway established across the MoS2/g-C3N5 interface, which simultaneously preserves strong redox potentials and accelerates spatial carrier separation. This work establishes interfacial electronic engineering as a unifying strategy for designing multifunctional 2D heterostructures capable of coupling photocatalytic, electrocatalytic, and sensing functionalities within a single material platform. 2026-01-01T00:00:00Z