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ThesisItem Open Access Study on compact solid battery fabrication using activated carbon prepared by using different ratio of Zncl₂(Department of Physics, OUAT, Bhubaneswar, 2020) Nayak, Vandana; Dash, Namita; Das, Susant Kumar; Acharya, Manas RanjanIn this study, activated carbon has been synthesized by a high-temperature using ZnCl2 as an activator or electrolyte. This study proposes an electrochemically activated ZnCl2 battery using lee-expensive carbon felt to maintain efficient electron percolation in the cathode and evaluates the charge-discharge behavior and cell impedance. Activated carbon is produced through drying the washed charcoal under sunlight, mixing the charcoal with zinc chloride solution (zinc chloride+distilled water) and heating the slurred charcoal in microwave oven procedure for 90 minutes at 250 degree Celsius. Now the activated carbon is produced, which is used to make a compact battery. The main aim of making such battery cell is to calculate the discharging properties, the ampere hour capability of battery and lastly the VT, IV characteristics of the battery. Zinc chloride is commonly used activator in chemical activation of activated carbon. Various carbonaceous materials have been studied as potential source of activated carbon. The operating conditions are, manipulated with attention to improve the properties and performance of activated carbon in the adsorption of water pollutants. However, the generalized attributes of zinc chloride activation in relation to the adsorptive performance of activated carbon are not well documented in much of published literature. Therefore, the present work is aimed to highlight the activation strategies and mechanisms of zinc chloride activation of activated carbon. The roles of impregnation ratio, period of activation and temperature are discussed to offer some insight into textural characteristics of activated carbon. The case studies on methylene blue adsorption are integrated to shed light on the external factors affecting the adsorption.ThesisItem Open Access Study of Dielectric relaxation of graphene oxide(Department of Physics, OUAT, Bhubaneswar, 2019) Nayak, Shibani; Baag, Sushama; Parida, Chhatrapati; Acharya, Manas RanjanHerein this present work graphene oxide(GO) and by its subsequent reduction using ascorbic acid reduced graphene oxide(RGO) are synthesized using Hummers method.. Go and RGO pellets are prepared using polyvinyl alcohol and characterized by XRD, FTIR and UV spectroscopy.The characterization results revealed presence of oxygen containing functional groups such as hydroxyl, carbonyl, carboxylic group in GO and the removal of these functional groups after treatment with ascorbic acid. The dielectric and impedance parameters of GO pellets has been studied in the frequency range 1 Hz to 1MHz and in the temperature range 300C to 100 0C.The result demonstrate giant dielectric permittivity of GO (∼105) with low loss at 1 Hz and at 30 °C, which is even very high compared to conventional dielectric materials such as CaCu3Ti4O12 and perosvkites. The dielectric constant of GO decreases to 75 at frequency of 1MHz.The ac conductivity of our GO was calculated and found to be 4 × 10−5 ohm-1cm-1at 1Hz and 75 × 10−5 ohm-1cm-1 at 1 MHz .The variation of dielectric constant, dielectric loss, ac conductivity of GO with varying frequency and varying temperature are assessed using dielectric spectroscopy. The role of functional groups, frequency and temperature are elucidated and discussed with regard to the high dielectric constant. The present findings suggest that the GO can be used for scaling advances high performance electronic devices and high dielectric-based electronic and energy storage devices.ThesisItem Open Access Study of surface structure and optical properties of PMMA films treated for different time in DC glow discharge (air) plasma(Department of Physics, OUAT, Bhubaneswar, 2019) Acharjya, Debadutta; Panigrahi, Manorama; Parida, Sabyasachi; Acharya, Manas RanjanIn this paper PMMA films were prepared by solution casting method and were subjected to DC glow discharge (air) plasma treatment for different intervals of time(2.5 min ,5 min ,7.5 min). The films were then characterized through techniques like FTIR, UV-Vis, SEM to study their surface structure and optical properties. FTIR analysis revealed that there were no new peaks or peak shift observed in the treated films. While the characteristic intensity decreased with increase in treatment time which is due to decrease in no. of bonds and interaction of PMMA film surface with the electron, ion, radical and UV radiation of plasma. Study of UV-Vis analysis showed us that there was an increase in the transmittance percentage during shorter time treatment (2.5 min) because surface impurities were reduced and hydroxyl groups were reduced. But during longer time treatment (5 min, 7.5 min) transmittance decreased due to generation of electrons on PMMA surface due to the effect of plasma. There were no significant changes in bandgaps of the films reported due to low power plasma treatment which was confirmed from other researchers. The SEM micrographs indicated that the roughness of films increased with increase in treatment time. This result also confirmed the result of transmittance of UV-Vis analysis.ThesisItem Open Access Synthesis and structure studies of SrMnO3 perovskite oxide(Department of Physics, OUAT, Bhubaneswar, 2019) Parida, Jitendra; Mohanty, Basanti; Kissan, Bhagaban; Acharya, Manas RanjanIn this study ,I have taken the SrCO3 and MnO2 in stoicheometry proportion for getting synthesized SrMnO3 . After taking this compound I had to grind it both in air as well as in wet medium for five hours. Then the prepared compound was calcinated about the temperature 1200ª. And this process was repeated many times to get the correct one. Finally the prepared compound was characterized using had been send for characterization such as XRD and Raman spectrometer. X-ray diffraction scan showed that the sample was poly crystalline in nature with a combination of hexagonal and cubic phases. The phonon modes in lower frequenciesy region 100-400 cm-1 were found to be originating in-phase and out-phase. However in the higher frequency range from 400-700 cm-1, the modes are originating from twisting or breathing of face sharing triangle of O-ion parallel or perpendicular to c-axis.ThesisItem Open Access Temperature dependent dielectric relaxation of graphene oxide(Department of Physics, OUAT, Bhubaneswar, 2019) Lenka, Linkan Ku.; Parida, Chhatrapati; Acharya, Manas RanjanIn this study, graphene oxide(GO) was synthesized following Hummers method and further reduced by ascorbic acid to obtain reduced graphene oxide(RGO). Physio-chemical characterization of Go and RGO are done by XRD, FTIR and UV spectroscopy.The results obtained from the characterization revealed presence of oxygen containing functional groups like hydroxyl, carbonyl and carboxylic group in GO and the removal of these functional groups after treatment with ascorbic acid. .The dielectric properties of GO pellets such as dielectric constant, dielectric loss, ac conductivity and complex impedance were studied in the temperature range from 300C to 100 0C keeping frequency constant. .A high dielectric constant of GO (∼105) with low loss was observed at 1 Hz and at 35 °C, which is even very high compared to conventional dielectric materials such as CaCu3Ti4O12. The ac conductivity of our GO was calculated and found to be 4 × 10−5ohm-1cm-1 at 1Hz and 75 × 10−5 ohm-1cm-1at 1 MHz .The various mechanisms governing the variation of dielectric constant, dielectric loss, ac conductivity of GO with varying temperature are assessed using the role of functional groups present in GO. The present findings suggest that the GO can be used for scaling advances high performance electronic devices and high dielectric-based electronic and energy storage devices like in super capacitors.ThesisItem Open Access Synthesis and Characterisation of Graphene Oxide (GO)(Department of Physics, OUAT, Bhubaneswar, 2019) Dash, Preetisudha; Baag, Sushama; Parida, Chhatrapati; Acharya, Manas RanjanIn this study, graphene oxide(GO) was synthesized following Hummers method and further reduced by ascorbic acid to obtain reduced graphene oxide(RGO). Go and RGO are characterized by XRD, FTIR and UV spectroscopy.The characterization revealed presence of oxygen containing functional groups in GO and the removal of these functional groups after treatment with ascorbic acid.The dielectric study of GO pellets demonstrate its high dielectric permittivity in the frequency range of 1 Hz to 1 MHz . A high dielectric constant of GO (∼105 ) with low loss was observed at 1 Hz and at 35 °C, which is even very high compared to conventional dielectric materials such as CaCu3Ti4O12. The ac conductivity of our GO was calculated and found to be 4 × 10−5 ohm-1 cm-1 at 1Hz and 75 × 10−5 ohm-1 cm-1 at 1 MHz .The various mechanisms governing the variation of dielectric constant, dielectric loss, ac conductivity of GO with varying frequency are assessed using dielectric spectroscopy. The mechanistic approach and the role of functional groups, t and frequency are elucidated and discussed with regard to the high dielectric constant.The present findings suggest that the GO can be used for scaling advances high performance electronic devices and high dielectric based electronic and energy storage devices.ThesisItem Open Access Dosage effect of SUB1 genes on morpho-physiological traits and submergence tolerance in rice(Department of Botany, OUAT, Bhubaneswar, 2021) Khuntia, Priyabrata; Chakraborty, Koushik; Dash, Debasis; Purohit, ParamitaThe present study was aimed to evaluated the dosage effect of SUB1 genes (present inside SUB1 QTL region) on submergence tolerance ability of rice. For this, three rice genotypes i.e. Swarna, Swarna-Sub1 and F1s derived from Swarna × Swarna-Sub1 were taken and they were subjected to two weeks of complete submergence stress. Genotypic profiling of these three lines by AEX1 and SUB1BC2 markers confirmed presence of SUB1A1 specific allele in the F1s. The thickness of leaf gas film (LGF), epicuticular wax content and leaf hydrophobicity traits of the normally grown plants were significantly higher in the F1s as compared to the susceptible parent Swarna, while most of these traits were at par with their tolerant parent Swarna-Sub1. Upon imposition of submergence stress, we observed 78% survival rate in the F1s, while it was 91% in Swarna-Sub1 and 14% in Swarna. Similarly, increase in underwater plant height determined in terms of elongation percentage was 38%, 10% and 15% in Swarna, Swarna-Sub1 and F1s, respectively. Although, there was not much difference in initial chlorophyll content in these three lines but after 14 days of submergence it was completely depleted in Swarna (0.2 mg g-1 FW), while it was still higher Swarna-Sub1 (1.3 0.2 mg g-1 FW) and F1s (0.9 0.2 mg g-1 FW). Similarly, the leaf starch content was also much higher in both Swarna-Sub1 and the F1s (>36 mg g-1 DW) as compared to Swarna (21 mg g-1 DW) after submergence stress. The pattern of underwater depletion of LGF and leaf hydrophobicity of the F1s were also closer to their tolerant parent Swarna-Sub1 than susceptible parent Swarna as observed in the present study. From this study, it can be concluded that even a single copy of the SUB1 genes (SUB1A1 in particular), is able to impart significant tolerance to submergence stress in rice and the phenotypic expression of the F1s derived from Swarna × Swarna-Sub1 crosses were more similar to the tolerant parent Swarna-Sub1 than Swarna.ThesisItem Open Access Chromium toxicity on antioxidative enzymes of plants(Department of Botany, OUAT, Bhubaneswar, 2021) Behera, Ronalisa; Dash, Debasish; Purohit, Parimita; Singh, LaxmiChromium is an essential element for plant growth and development, its harmful effects can’t be escapable. Toxic effects of Chromium on plant depend primarily on its valance state, the hexavalent form[Cr (VI)]is highly toxic and mobile whereas the trivalent form [Cr (III)] is less toxic for plants. Since Cr has no particular uptake pathway or mechanism; Cr is taken up along with the essential elements such as sulfate. Cr accumulation in plants causes harm in terms of reduction in growth and biomass accumulation. Cr interferes in photosynthetic, respiration process, water and mineral uptake mechanism leading plant cell to death. Various enzymatic activities related to starch and nitrogen metabolism are decreased by Cr toxicity either by direct involvement with the enzyme or through the production of reactive oxygen species. Cr causes oxidative damage by destruction of membrane of lipid and DNA damage. It also includes degradation of photosynthetic pigments causing deterioration in growth. Chromium even may cause death to plant species. The present study include on the effect and mechanism of Chromium (Cr) stress in plantThesisItem Open Access Gut microbiota of snail (Pila globosa) is influenced by reduced graphene oxide(Department of Biotechnology, OUAT, Bhubaneswar, 2021) Nayak, Supriya; Das, Kajari; Mishra, C.S.K.; Patnaik, Srianga TilakSnails are most abundant and significant groups of molluscs and act as eco toxicological indicator. In this study the Indian apple snail i.e. Pila globosa was treated with RGO nanoparticles. Then microbiological experiment was done to observe effect of RGO on antioxidant defence system and whether RGO nanoparticles induces the microbiota inside the intestine of the snails. Our results show that the RGO is responsible to induce microbial growth in intestine at high concentration.
