Zn-ferrite (ZnFe2O4) thin films were deposited by rf-magnetron sputtering on glass substrates at room temperature (RT) in pure oxygen environment. The as-deposited films were investigated by x-ray diffraction to show that single phase nanocrystalline spinel patterns belong to zinc ferrite. The magnetization shows ferrimagnetic behavior, and it strongly depends on oxygen working pressure. The maximum magnetization of 230 emu/cm3 (42 emu/g) at RT is obtained for the film deposited at 27 mTorr of oxygen pressure. The oxygen vacancy concentration and random distribution of Zn2+ and Fe3+ on both tetrahedral and octahedral sites are the possible reasons of high magnetization due to rapid cooling of sputtered vapors to form solid state film. The optical properties of the films show 85% transparency above 550 nm wavelength. The estimated values of direct and indirect band gaps are 2.5 and 1.9 eV, respectively.

Thin films of zinc ferrite (ZnFe2O4) were deposited on glass substrates at room temperature in pure argon and pure oxygen environments by RF-magnetron sputtering. The structural and optical properties of the films were studied as a function of pure O2 pressure using an RF power of 100 W. The XRD data show the film having a spinel structure. The AFM images show the nanocrystalline nature of the films. The particle size depends on the environment and varies between 55 and 75 nm. The smaller value is obtained for the film deposited under the pure argon environment. The optical constants of the films were extracted from the transmission spectra by the envelope method. The estimated direct energy band gap values for the film deposited at 8 mTorr of gas pressure in pure Ar is 2.43 eV. For the films deposited in pure O2, the band gap increases from 2.48 to 2.61 eV as the O2 pressure is increased from 8 to 31 mTorr. The dispersion of the refractive index (n) is discussed in terms of the single-oscillator Wemple–DiDomenico model. This model is also used to estimate the dispersion parameters and the static refractive index.

Rainfall variability and water scarcity continue to hamper the food and income security of smallholder farming systems in poverty-affected regions. Innovations in soil and water management, especially in the drylands, are critical for meeting food security and water productivity targets of Agenda 2030. This study analyzes how rainfed agriculture can be intensified with marginal impact on the landscape water balance. The impact of rainwater harvesting structures on landscape hydrology and associated agricultural services was analyzed in the semi-arid Jhansi district of Bundelkhand region in central India. The Parasai-Sindh pilot watershed was subjected to a 5-year (2012-2016) monitoring of rainfed system improvements in water availability and crop intensification due to surface water storage (haveli system), check dams, and field infiltration structures. Hydrological processes were monitored intensively to analyze the landscape's water balance components. Rainwater harvesting (RWH) structures altered the landscape's hydrology, limiting average surface runoff from 250 mm/year to 150 mm/year over the study period. Groundwater levels increased by 2-5 m (m), alleviating water scarcity issues of the communities in recurring dry years. Nearly 20% of fallow lands were brought under cultivation.

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The temperature dependent electron spin resonance (ESR) studies on Bi(1−x)CaxMnO3 (x=0.4, 0.45, and 0.5) having a triclinic structure were carried out to understand the spin dynamics, short-range magnetic interactions, and micromagnetic phase formation in these materials. The phase transition into charge-ordered (CO) state takes place at temperatures TCO=313K (for x=0.4 and 0.5) and at 317K (for x=0.45) samples. The data are explained in view of the existence of mixed valence clusters of Mn3+–Mn4+ ions coupled by strong short-range ferromagnetic (FM) double-exchange interactions in the paramagnetic state. The orbital ordering changes from FM to antiferromagnetic (AFM) type ∼190K (for x=0.4 and 0.5) and ∼180K (for x=0.45). The Néel Temperatures TN are 163K (for x=0.4 and 0.5) and 153K (for x=0.45). The temperature independence of ln (DI) double integrated intensity of the ESR resonance below 125K is ascribed to the existence of FM ordered microinhomogeneities embedded in the AFM ordered bulk sample. The TCO and TN values are found to be weakly dependent on the composition. The temperature dependence of ESR linewidth near TN has been analyzed in view of the spin-spin relaxation near magnetic critical points, as given by Seehra and Huber [AIP Conf. Proc. 24, 261 (1975)].