http://irgu.unigoa.ac.in/drs/handle/unigoa/5626 2026-06-04T10:15:23Z 2026-06-04T10:15:23Z Costa, S.O. Priolkar, K.R. Verenkar, V.M.S. http://irgu.unigoa.ac.in/drs/handle/unigoa/7875 2026-06-04T09:24:41Z 2026-01-01T00:00:00Z

Impact of Mn substitution on Ni-Zn ferrites towards structural, electrical, magnetic, gas sensing, and electrochemical properties Costa, S.O.; Priolkar, K.R.; Verenkar, V.M.S. Zn sub(0.5-x)Mn sub(x)Ni sub(0.5)Fe sub(2)O sub(4) (x = 0.0, 0.1, 0.2, 0.3, 0.4, 0.5) ferrites were synthesized via the combustion route using malic acid as fuel. ICP-AES confirmed the desired stoichiometry of the synthesized ferrites. XRD studies revealed crystallite sizes of 10-23 nm, and with increasing Mn concentration, the lattice parameter decreased. SEM and HR-TEM analyses revealed particles in the nanoscale range. XPS studies confirmed the oxidation states of the constituent metal cations as Mn sup(3+), Fe sup(2+)/Fe sup(3+), Ni sup(2+), and Zn sup(2+). Mn K-edge XANES measurements further confirmed the presence of Mn in the +3 valence state occupying both tetrahedral and octahedral sites in the ferrite lattice. BET surface analysis indicated mesoporosity, with surface areas ranging from 24.26 to 49.06 m sup(2)/g. Electrical resistivity measurements confirmed the semiconducting nature of ferrites, and a decrease in resistivity with increasing Mn concentration was observed. Magnetic studies revealed soft ferrimagnetic behavior in the ferrites, with the saturation magnetization decreasing and the Curie temperature increasing as the manganese concentration increased. Gas sensing tests demonstrated high sensitivity (53 percent), high selectivity, and rapid response (3 s) and recovery (3 s) for composition x = 0.1 towards NO sub(2) gas. Electrochemical analysis showed charge storage behavior, with a specific capacitance of 101.35 F/g for x = 0.4. Collectively, the results demonstrate that systematic substitution of manganese can effectively tailor Ni-Zn ferrites into high-performance multifunctional materials for gas sensing and supercapacitor applications.

2026-01-01T00:00:00Z Vaigankar, C. Gaude-Agadyekar, V. Kakodkar, E. Kunkalekar, R.K. Joshi, N. http://irgu.unigoa.ac.in/drs/handle/unigoa/7860 2026-04-30T06:14:07Z 2026-01-01T00:00:00Z

Comparative evaluation of plasma-assisted and photochemical advanced oxidation processes for p-nitrophenol degradation in water Vaigankar, C.; Gaude-Agadyekar, V.; Kakodkar, E.; Kunkalekar, R.K.; Joshi, N. The present study examined the degradation of p-nitrophenol (PNP), a hazardous and long-lasting nitroaromatic contaminant commonly found in industrial wastewater, through a comparative analysis of various treatment methods utilizing CuO-Fe sub(2)O sub(3) mixed oxide catalysts. The effectiveness of adsorption, photocatalysis, photo-Fenton oxidation, catalytic ozonation, plasma treatment, and plasma-assisted catalytic oxidation was thoroughly evaluated under controlled settings. Among the evaluated catalysts, the C3 (CuFe sub(2)O sub(4)) catalyst exhibited the highest adsorption capacity and catalytic efficiency, facilitating the effective degradation of PNP via various advanced oxidation processes. Photocatalytic degradation under UV light resulted in significant PNP removal, whereas the UV-H sub(2)O sub(2)-catalyst system achieved nearly complete degradation (98-100 percent) within 10 min, owing to enhanced hydroxyl radical (.OH) generation via combined photolytic and catalytic processes. Catalytic ozonation further boosted degradation efficiency by facilitating the surface-mediated decomposition of ozone (O sub(3)) into reactive oxygen species. Plasma treatment produced several oxidizing agents, including O sub(3), nitrite (NO sub(2-), nitrate (NO sub(3)-), hydrogen peroxide (H sub(2)O sub(2)), and reactive radicals, which accelerated the oxidative degradation of PNP. This comparative assessment underscores the synergistic effect of catalyst-assisted radical generation in accelerating pollutant degradation and offers insights into selecting appropriate advanced oxidation methods for effectively treating nitroaromatic pollutants in water.

2026-01-01T00:00:00Z Shruthi, N.R. Das, B.V. Kamat, V. Akki, M. Barretto, D.A. Poojary, B. Venugopala, K.N. http://irgu.unigoa.ac.in/drs/handle/unigoa/7859 2026-04-30T06:13:18Z 2026-01-01T00:00:00Z

S-alkylated pyridyl-linked oxadiazole thione derivatives: Synthesis, dual Alpha-amylase/Alpha-glucosidase inhibition, and anti-inflammatory evaluation Shruthi, N.R.; Das, B.V.; Kamat, V.; Akki, M.; Barretto, D.A.; Poojary, B.; Venugopala, K.N. In type II diabetes mellitus, inhibition of the enzymes Alpha-amylase and Alpha-glucosidase is an effective strategy for managing postprandial hyperglycemia. Given the therapeutic significance of Alpha-amylase and Alpha-glucosidase inhibition, this study reports the synthesis of twelve S-alkylated pyridyl-linked oxadiazole thione derivatives from 2-chloronicotinic acid via a multistep synthetic route, evaluated as potential antidiabetic agents, which have been well characterized by FT-IR, sup(1)H/ sup(13)C NMR, and mass spectroscopic techniques. The synthesized compounds were docked with target proteins Alpha-glucosidase (PDB: 3L4Y) and Alpha-amylase (PDB: 4GQR). All synthesized compounds were assessed in vitro for their inhibitory activity against Alpha-amylase and Alpha-glucosidase, along with their anti-inflammatory potential. Compound 6f showed excellent Alpha-amylase and Alpha-glucosidase, and 6g showed anti-inflammatory properties among all the screened compounds.

2026-01-01T00:00:00Z Petrosyan, A.M. Srinivasan, B.R. http://irgu.unigoa.ac.in/drs/handle/unigoa/7842 2026-04-24T06:23:12Z 2026-01-01T00:00:00Z

Comments on "growth mechanism and physicochemical properties of L-threonine silver nitrate (LTSN) single crystal for frequency doubling and optical limiting applications" Petrosyan, A.M.; Srinivasan, B.R. The authors of a recent publication (Moses et al. in: J. Mater. Sci.: Mater. Electron. 37:307, 2026) report having grown and studied a new crystal "L-threonine silver nitrate" (LTSN) by the slow evaporation solution growth method. In this letter to the Editor, many points of criticism concerning the synthesis and characterization of the so-called LTSN crystal are described to prove that it is a material of unknown composition.

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