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2019 - 201912020 - 20235
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Subject: Physics × Start date: 2019 × Thesis Type: M.Sc ×
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Now showing 1 - 6 of 6
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    ThesisItemOpen Access
    Synthesis of tin disulphide (SnS2) and its characterization
    (CCSHAU, HISAR, 2022-07) Deepika Rani; Vinay Kumar
    The utilization of two dimensional materials in electronic and optical appliances is increasing day by day because of their excellent properties which can be utilized in various applications. The goal of the current study is to synthesize tin disulphide by low cost, wet chemical method at room temperature. To investigate its morphology, size, structure, and optical characteristics, different characterization techniques were used including FTIR, XRD, UV-Vis spectroscopy, PL spectroscopy, FESEM. FTIR spectra show Sn-S and S-S stretching vibrations which provide verification for the fabrication of SnS2. The band gap obtained from PL spectrum was found almost of the same order as obtained from UV-Vis spectrum. FESEM pictures represent the well-defined spherical morphology of the prepared SnS2. The XRD outcomes show the crystalline nature of the SnS2.
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    ThesisItemOpen Access
    To study morphological and optical properties of doped zinc sulfide
    (CCSHAU, Hisar, 2023-05) Janvi; Vinay Kumar
    Zinc Sulphide (ZnS) is a semiconductor receiving discernible attention as a nanomaterial scale because of excellent ion accessibility, charge storage ability, enhanced luminescent efficiency and lifetime shorting in comparison to that of bulk. However, doping of manganese (Mn) ion enhances its optoelectronic properties due to large exciton energy and wide bandgap at room temperature. ZnS and Mn-doped ZnS have been synthesized using the hydrothermal approach with 5, 10, and 20 % of Mn dopants. Prepared samples were characterized using X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDX), Field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR), UV-Vis and Photoluminescence (PL) spectroscopy. The XRD pattern confirmed the cubic sphalerite crystal structure of prepared nanoparticles (NPs) whereas FE-SEM micrographs showed sphere-shaped NPs. The EDX spectrum measurements showed that spectra of Mn-doped ZnS exhibit peak related to elemental Mn. The stretching mode of undoped ZnS was observed at 636 cm -1 and the Zn-S-Zn network was perturbed by the presence of Mn. The energy bandgap was found to be decreased with increasing doping percentage from 5 to 20%, which is agreed to XRD. The PL spectra of Mn-doped ZnS showed at room temperature exhibit both the blue defect-related emission and orange Mn +2 emission due to the 4 T1 – 6A1 transition.
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    ThesisItemOpen Access
    Fabrication of bismuth telluride thin film and study of its electrical properties
    (CCSHAU, Hisar, 2023-05) Pooja; Paul Singh
    In this study, thin films of Bismuth Telluride were fabricated successfully by using thermal evaporation method onto different substrates (i.e., glass and silica) at ambient temperature. Their structural, morphological, optical and electrical properties were investigated by using X-ray diffraction (XRD), Field Emission-Scanning Electron Microscopy (FE-SEM), Photoluminescence (PL) sepectrooscopy and SourceMeter Instrument, respectively. The FT-IR study showed that the prepared Bismuth Telluride films do not show any transmittance spectra. The XRD analysis revealed that the films were crystalline in nature. The surface mimages showed that the prepared films have a homogeneous and compact grain surface. The calculated optical band gap was about 2 eV for both types of film. The I-V characteristics of prepared thin films were analyzed at temperature ranges from 30°C to 100°C. It was found that the films fabricated onto silica substrates showed larger electrical conductivity than that of the films fabricated onto glass substrates. Also, the increment in electrical conductivity was observed with the temperature showing that the prepared films have negative temperature coefficient of resistance and exhibit the semiconductor behaviour.
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    ThesisItemOpen Access
    Characterization of biochar prepared from coconut shell at different temperatures
    (CCS HAU, Hisar, 2022-07-22) Bhawna; Dahiya, Rita
    Pyrolysis process can be the solution to problems that arises due to the improper management of biowaste. This process might be used to produce valuable carbonaceous products like biochar. The present study is focused on the preparation of biochar from coconut shell at different temperatures by pyrolysis. The obtained biochar was characterized by using analytical techniques like FTIR, XRD, BET, FE-SEM and UV-Vis spectroscopy. The properties of biochar like ash content, EC, pH, carbon content and CEC were also determined using standard methods. The FTIR spectra of the prepared biochar confirmed the presence of aromatic carbon functional group in the biochar structure. From the XRD plots, amorphous structure of the biochar is confirmed. The results indicated that as the pyrolysis temperature increased, the amorphous organic phase in the biochar structure decreased. The FE-SEM images showed the porous structure of biochar prepared at a high temperature of 700 °C. The BET analysis showed that as the pyrolysis temperature increased, surface area as well as porosity of the biochar increased.
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    ThesisItemOpen Access
    Study on temperature dependent dielectric properties of edible oils for quality assessment
    (CCS HAU, Hisar, 2022-07-22) Meena; Paul Singh
    Edible oils adulteration has remained a global issue for years. Being an essential element of our daily diet, quality assessment of edible oils has become necessary. The present work focuses on use of dielectric properties for quality assessment of edible oils. The dielectric properties of edible oils (groundnut, mustard, sunflower and sesame) such as dielectric constant and electrical conductivity were investigated in a frequency range between 900 to 2700 MHz by using a dielectric assessment kit (DAK). With increase in palm oil adulteration, the dielectric constant of groundnut and mustard oil increased while for sunflower and sesame oil, it slightly decreased. For all the oil samples, electrical conductivity showed a slight change with increase in palm oil adulteration. The dielectric constant and electrical conductivity of oils were also analysed at different temperatures and at repetitive heating cycles. Both dielectric constant and electrical conductivity increased with increase in temperature and number of repetitive heating cycles.
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    ThesisItemOpen Access
    Estimation of soil thermal properties in long-term zero tillage practice under mungbean-wheat and sorghum-wheat cropping systems
    (CCSHAU, 2019) Mallo Devi; Dahiya, Rita
    Thethermal properties of soil have significanct role on soil productivity and plant growth. Therefore, the present study on “Estimation of soil thermal properties in long-term zero tillage practice under mungbean-wheat and sorghum-wheat cropping systems” was conducted during 2018-19 at Research Farm of Department of Soil Science, CCS HAU, Hisar. The field experiments consisted of three tillage practices viz. CT-CT (Conventional tillage in both kharif&rabi seasons), CT-ZT (Conventional tillage in kharif&zero tillage in rabi seasons) and ZT-ZT (Zero tillage in both kharif& rabi seasons); two cropping systems (sorghum-wheat and mungbean-wheat) and two moisture regimes (IW/CPE = 0.75 and 0.90). Soil physico-chemical properties i.e., soil organic carbon, bulk density, soil moisture contents were measured at 0-5, 5-15 and 15-30 cm depth in all the three tillage practices inboth the cropping systems and moisture regimes. The soil temperatures were measured at 2, 5 and 15 cm depths in all the treatments at different times on different days during the study period. The soil penetration resistance was measured at 20 cm depth in all the three tillage practices under both the moisture regimes in both the cropping systems. The specific heat capacity (0-5, 5-15 and 15-30 cm), thermal diffusivity (0-15 cm) and thermal conductivity (0-15 cm) of soil were determined in all the three tillage practices in both the moisture regimes in both the cropping systems. The zero tillage (ZT-ZT) significantly increased the soil organic carbon upto 30 cm depth as compared to CT-CT in both the cropping systems and moisture regimes. The adoption of zero tillage reduced the bulk density of soil as compared to CT-CT up to 15 cm depth significantly in both the cropping systems and moisture regimes. Penetration resistance of soil was found lowest in ZT-ZT amongst all the tillage practices at 20 cm depth. Zero tillage increased the soil moisture up to 30 cm depth as compared to CT-CT. The specific heat capacity was found highest in ZT-ZT , thermal diffusivity and thermal conductivity was found lowest in ZT-ZT in both the cropping systems in both the moisture regimes. The results indicated that zero tillage has potential to enhance the soil organic carbon, reduce soil compaction and moderate the soil temperature in arid and semi-arid climate conditions.