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La-based Perovskite-type oxides with composition La1-xCuxCoO3 (0 ≤ X ≤ 0.8) have been synthesized by malic acid sol-gel low temperature route at pH 3.75. In each preparation, nitrate salts of lanthanum, copper, cobalt and malic acid were taken as starting material. The pH of the solution was adjusted by using ammonia solution. Techniques used to know the physical properties of the materials were scanning electron microscope (SEM) powder X-ray diffraction (XRD). All the electrochemical viza cyclic voltammetry, roughness factor and anodic polarization studies have been performed in three electrode single compartment glass cell. For the purpose, materials were transferred in the form of oxide film electrode on Ni conducting support. XRD data showed the formation of almost pure phase of the material with hexagonal crystal geometry. The cyclic voltammetric study showed that each oxide electrode exhibited a pair of redox peaks prior to the oxygen evolution reaction (OER). The values of Tafel slope (78-90 mV decade-1) and reaction order (~ 1) indicate that each catalyst follows similar mechanistic path. The data of anodic polarization study shows that the substitution of Cu in place of La in the base oxide increases the electrocatalytic activity considerably. The value was found to be highest with 0.4 mol Cu substitution. Electrochemically active area of the material was determined in terms of roughness factor by recording the cyclic voltammograms at different scan rates in the potential region 0.0-0.1V. The roughness factor was observed to be highest with 0.2 mol Cu-substituted oxide.

Some ternary ferrites having composition CoxNi1.5-xFe1.5O4 (0.0 ≤ x ≤ 1.25) have been synthesized by NH4OH co-precipitation method at 11.5 pH. Materials, so obtained, were tested for their electrocatalytic properties towards oxygen evolution reaction (OER) in the form film on Ni-support in alkaline solution. The study showed that the electrocatalytic properties the material increased with partial substitution of Co for Ni in the base oxide (Ni1.5Fe1.5O4). The value being highest with 0.5 mol Co-substitution. At E = 850 mV vs Hg/HgO in 1M KOH at 25 ºC, the electrode showed apparent current density 206.2 mA cm-2, which is about 3 times higher than the base oxide. The Tafel slope values were ranged between 46-82 mV decade-1. A pair of redox peak, an anodic (EPa = 522±28 mV) and corresponding cathodic (EPc= 356±9 mV), was observed in the cyclic voltammetry (CV) study of the material. The thermodynamic parameters namely, standard apparent electrochemical enthalpy of activation ( ), standard enthalpy of activation ( ) and standard entropy of activation ( ) for the oxygen evolution reaction (OER) have also been determined by recording anodic polarization curve in 1M KOH. The value of was observed to be almost similar with each oxide electrode. The values were highly negative and ranged between ~ -165 and ~ -207 J deg-1 mol-1. Phase and morphology of materials have been investigated by using physical techniques X-ray diffraction, infrared spectroscopy (IR) and scanning electron microscope (SEM), respectively.

Some binary ferrites having molecular formula, MnxFe3-xO4 (0 ≤ x ≤ 1.5) have been synthesized by a simple and cost effective egg white sol-gel route. In each preparation, nitrates of constituent metal were taken as starting materials and egg white as gelling agent. The material, thus obtained was altered in the form of film electrode on the pre-treated Ni- support using an oxide-slurry painting tech-nique and investigated as electrocatalysts for the oxygen evolution reaction in KOH solutions. The study showed that Mn-substitution in the base oxide matrix influences the electrocatalytic activity of the material significantly and found to be greatest with 0.5 mol Mn-substitution. The reaction order has been found to be approximately unity with respect to OH¯ concentration. The Tafel slope values at low potential ranged between ~ 52 and ~ 65 mVdecade-1. The thermodynamic parameters namely, standard apparent electrochemical enthalpy of activa-tion (), standard enthalpy of activation () and standard entropy of activation () for the oxygen evolution reac-tion (OER) have also been determined. It has been observed that and values decreased with Mn-substitution in the Fe3O4 lattice. This decrease inandwas found to be greatest with 0.5 mol Mn. Thevalues were also found to be highly negative varying between ~ - 185 and – 211 J deg-1 mol-1.

Dispensation of fresh produce especially fruits through radiation, involves exposure to short wave energy to achieve a specific purpose viz. reduce the weight loss and extend the ripening. An experiment was carried out to study the effect of irradiation and storage conditions in Alphonso mango on physiological weight loss and ripening. The experiment was laid out in completely randomized block design with factorial concept with three repetitions. The fruits were exposed to gamma radiation for different doses from the source of 60Co at Board of Radiation and Isotope Technology, Bhabha Atomic Research Centre, Mumbai. There were sixteen treatment combinations of irradiation dose (I1 -0.00, I2 -0.20, I3 -0.40 and I4 -0.60 kGy) and storage temperature (S1-Ambient, S2-9°C, S3-12°C and S4-CA storage (12°C, O2 2%, CO2 3%). The data indicated that the fruits irradiated with 0.40 kGy gamma rays (I3) recorded significantly minimum percent reduction in physiological loss in weight and extended the ripening. Similar pattern was noted when fruits were kept at 9°C storage temperature. Combined effect of 0.40 kGy gamma rays irradiation and 9°C storage temperature (I3S2) also recorded maximum reduction in the physiological loss in weight and ripening percent throughout the storage period. Key words: Gamma rays, Mangifera indica L., postharvest, 60Co, refrigeration.

Alphonso mango fruit has high nutritional values, pleasant flavor, delicious taste as well as beautiful appearance and hence is known as the king of mango verities. The experiment was arranged from the 2008 and 2010 with 16 treatment combinations of irradiation dose (that is, 0.00, 0.20, 0.40, and 0.60 kGy) and stored at different storage temperatures viz., ambient at 27 ± 2°C and 60 to 70% RH, 9°C and 90% RH, 12°C and 90% RH, and Control atmospheric storage (12°C, O2 2%, CO2 3% and RH 90%). The fruits were exposed to gamma radiation from the source of 60Co. The two years collective data indicated that, the significantly minimum percent reduction in physiological loss in weight, reduced ripening percent, increased marketability of fruits, maximum total soluble solids, total and reducing sugars, and ascorbic acid content and minimum acidity were noted in 0.40 kGy gamma rays irradiated fruits stored at 12°C as compared to the other irradiated or unirradiated fruits stored at ambient condition and other storage environment. Suggestions were made for maximizing maintained physiological changes and quality by use of irradiation and adequate storage facilities for hygiene produce. Key words: Alphonso mango, irradiation, marketability, ripening, quality, storage temperature.

An experiment was carried out to study the effect of irradiation and storage temperatures on quality parameters in Kesar mango fruits. The fruits were exposed to gamma radiation of different doses i.e. 0.00, 0.20, 0.40 and 0.60 kGy) from 60Co source and stored at various storage environment viz., ambient temperature 27 ± 2 °C and RH 60–70 %; temperature 9 °C and RH 90 %; 12 °C and RH 90 % and control atmospheric (CA) storage at 12 °C, O2 2 %, CO2 3 % and RH 90 %. The data indicated that highest total soluble solids, total and reducing sugars and ascorbic acid contend and minimum acidity were noted in 0.40 kGy gamma rays irradiated fruits stored at 12 °C compared to unirradiated fruits stored at ambient condition at ripening stage.

In the present work, the ultraviolet absorption spectrum of 2,6-dichloro-3-nitro pyridine (2,6,3 DCNP) has been carried out experimentally (in water, n-hexane, ethanol, methanol and Mgo) and theoretically (in water, ethanol and methanol) in the range 3500–2300 cm−1 in the solution phase. Predicted electronic absorption spectra from time dependent density functional theory density functional theory (TD-DFT) calculation have been analyzed and compared with the experimental UV–Vis spectrum. The effects of chloro and nitro group substituent in pyridine ring have been analyzed. The electronic properties such as excitation energy, wavelength corresponding to absorption maxima \(\left( {\lambda_{max} } \right)\), oscillator strength (f), HOMO and LUMO energies are calculated by Time-Dependent Density Functional Theory (TD-DFT) using HF/6-311++G(d, p) and B3LYP/6-311++G(d, p) as basis sets. In addition Mulliken atomic charges of the atoms are also calculated.