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ThesisItem Restricted Synthesis and characterization of carbon based nanomaterials for water decontamination(Punjab Agricultural University, Ludhiana, 2022) Grover, Komal; Kiran JeetThe present study focuses on the synthesis of nanomaterials for the removal of Pb2+ ions from aqueous solution. Five adsorbents ie. Graphene Oxide (GO), Magnetic Graphene Oxide (MGO), Titanium Dioxide (TiO2), and their composites GO-TiO2, and MGO-TiO2 were synthesized. The prepared nanomaterials were characterized by High Resolution Imaging (HRI) and spectroscopic techniques. TEM images revealed the nanoscale structures of the synthesized nanomaterials. N2 adsorption-desorption studies revealed that the prepared GO was macroporous while all other adsorbents were mesoporous. Adsorption experiments were performed with the prepared GO, MGO, and TiO2. The maximum adsorption capacity Qm was found to be 46.19, 49.80 and 40.63 mg/g respectively at optimum pH of 6, contact time of 20 minutes, and temperature of 50℃. The prepared MGO was found to have high efficiency for the removal of Pb(II) ions from aqueous solution. Thermodynamic studies revealed that the adsorption process was spontaneous and endothermic.ThesisItem Embargo Properties of Metal Telluride Thin Films Embedded In Polyvinyl Alcohol Matrix(Punjab Agricultural University, Ludhiana, 2023) Neha; Rajeev KumarThe present research work describes the preparation of Cadmium Telluride nanocomposite embedded in Polyvinyl Alcohol matrix by using heat induced chemical methodology. PVA/CdTe nanocomposite thin films were further casted on glass substrates using Chemical Bath Deposition technique. The structural phase analysis and morphological study of PVA/CdTe nanocomposite was carried out by using X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM), respectively. It was confirmed that PVA/CdTe nanocomposite possesses a cubic zinc blend structure having nanocrystalline nature with average particle size of 6.4 nm. Fourier Transform Infrared (FTIR) spectroscopy was carried out for the identification of various chemical functional groups possessed by the PVA/CdTe nanocomposite. Various optical properties such as optical absorbance, transmittance, optical band gap, Urbach energy, refractive index, extinction coefficient, dispersion energy, single oscillator energy, dielectric properties and optical conductivity of PVA/CdTe nanocrystalline thin films casted at bath temperatures of 303 K, 313 K, 323 K, 333 K and 343 K were evaluated using UVVisible spectrophotometer. It was also revealed that energy band gap of the thin films showed a red shift as temperature increases for direct transitions of electrons. For the measurement of the optoelectronic characteristics of material, photoluminescence (PL) spectroscopy was carried out at bath temperature of 303 K in wavelength region from 300 nm to 600 nm., and observed a single narrow intensity peak at a wavelength around 445 nm. Different acoustical properties like adiabatic compressibility, acoustic impedance, intermolecular free length, relaxation time, attenuation coefficient and surface tension were studied for deep understanding of behavioural changes in particle-fluid interactions with change in bath temperature of PVA/CdTe nanocomposite. The properties of PVA/CdTe were found to be highly interdependent and influenced with change in temperature. Temperature dependent as well as frequency dependent capacitance-voltage characterisation was carried out for PVA/CdTe nanocomposite. Temperature dependent C-V parameters computed under reverse bias voltage such as barrier height, built in voltage and depletion width were found to decrease whereas carrier concentration increased with temperature. Interfacial state density for PVA/CdTe nanocomposite was evaluated using frequency dependent C-V profiling and it was found to decrease with increasing forward biasing.ThesisItem Open Access Water content estimation of direct seeded rice (Oryza sativa L.) using beta radiation(Punjab Agricultural University, Ludhiana, 2022) Virdi, Razdeep Kaur; Sharma, Rajeev KumarA field experiment was set up in split-plot design to use the beta radiation for estimating the water content (WC) of direct-seeded rice (Oryza sativa L.). Two varieties of rice PR 129 (V1) and PR 126 (V2) was grown under four irrigation treatments namely, V1I1 = irrigation based on IW/CPE ratio 3.0, V1I2 = irrigation based on IW/CPE ratio of 2.5, V1I3 = irrigation based on IW/CPE ratio of 2.0, V1I4 = irrigation based on IW/CPE ratio of 1.5 with, V2I1 = irrigation based on IW/CPE ratio of 3.0, V2I2 = irrigation based on IW/CPE ratio of 2.5, V2I3 = irrigation based on IW/CPE ratio of 2.0, and V2I4 = irrigation based on IW/CPE ratio of 1.5. 204 Tl has been used as a radioactive source with 0.766 MeV as end point energy. Logarithmic relative intensity versus thickness plots was fitted for the fresh and dry state of rice leaves for all treatments and mass attenuation coefficient (µm) values were used to evaluate WC. It was observed that µm was more for the dry state than for the fresh state of leaves. The findings show that maximum water content was in I4, followed by I3, I1, and minimum in I2 for both varieties. The obtained results of WC using beta attenuation were found in good agreement with the direct weighing method and comparable with relative leaf water content. Also, it was found that the least SDD was shown by I1 irrigation treatment, followed by I4, I3, and maximum SDD was observed in I2 for both varieties. Among the rice cultivar varieties: V1 and V2, minimal SDD was observed in V1. From the findings, it can infer that variety PR 126 (V2) with IW/CPE ratio of 1.5 (I4) is good for direct-seeded rice cultivar in the present study from more productivity. The beta attenuation technique is useful in WC estimation and can be effectively used in irrigation scheduling to conserve water.ThesisItem Restricted Effect of corn syrup impurity on dielectric properties and electrical conductivity of honey(Punjab Agricultural University, Ludhiana, 2021) Kehal, Kamaldeep Singh; Paramjit SinghThe present work has been done to evaluate the effect of adulteration of corn syrup on dielectric properties and electrical conductivity of honey. Honey was adulterated at five different concentrations (10%, 20%, 30%, 40% and 50%). All the measurements were taken at ten different frequencies (10, 20, 30, 40, 50, 60, 70, 80, 90 and 100 kHz) and five different temperatures (30º, 40º, 50º, 60º and 70º C). In addition to these parameters, density and viscosity were also determined at different temperatures. Dielectric constant decreased linearly with the increase in temperature, frequency and adulteration. Loss tangent increased linearly with increase in temperature and decreased exponentially with increase in frequency. Electrical conductivity increased linearly with the increase in temperature and frequency. Both loss tangent and electrical conductivity increased linearly with adulteration. Density decreased linearly with the increase in temperature and adulteration. Viscosity decreased exponentially with the increase in temperature and decreased linearly with the increase in adulteration. The data obtained were statistically analyzed using one-way analysis of variance at 5% level of significance. These parameters were found to vary significantly with adulteration. The constants and coefficients of these parameters-corn syrup relationships for honey were obtained. The regression equations developed relating dielectric constant, loss tangent, electrical conductivity, density and viscosity had high correlation coefficient (R2 > 0.898).ThesisItem Restricted Estimation of water content in maize (Zea mays L.) crop using beta radiation(Punjab Agricultural University, Ludhiana, 2021) Ramanpreet Kaur; Sharma, Rajeev KumarA field experiment was set up in split-plot design to use the beta radiations for estimating the water content (WC) of maize (Zea mays L.). Maize was grown having three nitrogen contents i.e. 90 kg ha-1 (N1), 120 kg ha-1 (N2) and 150 kg ha-1 (N3), and each was replicated thrice. 204Tl and 60Co have been used as radioactive sources with 0.766 MeV and 0.316 MeV as end point energies. Logarithmic relative intensity versus thickness were plotted for the fresh and dry state of maize leaves for all treatments, and mass attenuation coefficient (µm) was determined to be used to evaluate WC. It was observed that µm is more for dry leaves than for fresh leaves. Maximum WC was found in N1 followed by N2 and minimum is in N3. The obtained values of WC by using beta attenuation are found in good agreement with the direct weighing method and comparable with relative leaf water content. The index of stress degree day was evaluated and found minimum for N3 treatment. Also, the highest grain yield was obtained for N3 treatment. The study revealed that increasing Nitrogen content can reduce stress due to more temperature and less irrigation. Considering the results, it was inferred that N3 treatment would be best management intervention for maize cultivation. Beta radiations was found useful for estimation of WC and can effectively be used in irrigation scheduling for saving water.ThesisItem Open Access Higher order contributions to electron-acoustic solitary waves featuring cairns-tsallis distribution of electrons(Punjab Agricultural University, Ludhiana, 2019) Sharma, Anjali; Parveen BalaIn this thesis, a homogeneous system of unmagnetized and collisionless plasma constituting of cold electron fluid, immobile ions and hot electrons has been studied. The hot electrons are assumed to obey hybrid Cairns-Tsallis distribution. This distribution is applicable within the range and .Using standard Reductive Perturbation Method (RPM), dispersion relation and Korteweg de-Vries (KdV) equation has been derived. Reductive preturbation method is further extended to include the contribution of higher order terms. Renormalization method is employed in studying the propagation of electron acoustic solitary waves as well as higher order solitary waves. Our present investigation focuses on revealing the dependency of the behavior of these waves on nonthermal parameter( ), hot-to-cold electron density ratio( ), hot-to-cold electron temperature ratio( ), Mach number( ) and nonextensive parameter( ). Only negative potential structures are reported in our plasma model. The numerical results reflects that on taking the higher order correction terms into account, the amplitude of the dressed soliton solution increases however its width narrows. The present plasma model may be helpful in simulating the electron acoustic solitary behavior in the auroral regions and magnetospheric plasmas of earth.ThesisItem Open Access Higher order contributions to electron-acoustic solitary waves featuring cairns-tsallis distribution of electrons(Punjab Agricultural University, Ludhiana, 2019) Sharma, Anjali; Bala, ParveenIn this thesis, a homogeneous system of unmagnetized and collisionless plasma constituting of cold electron fluid, immobile ions and hot electrons has been studied. The hot electrons are assumed to obey hybrid Cairns-Tsallis distribution. This distribution is applicable within the range and .Using standard Reductive Perturbation Method (RPM), dispersion relation and Korteweg de-Vries (KdV) equation has been derived. Reductive preturbation method is further extended to include the contribution of higher order terms. Renormalization method is employed in studying the propagation of electron acoustic solitary waves as well as higher order solitary waves. Our present investigation focuses on revealing the dependency of the behavior of these waves on nonthermal parameter( ), hot-to-cold electron density ratio( ), hot-to-cold electron temperature ratio( ), Mach number( ) and nonextensive parameter( ). Only negative potential structures are reported in our plasma model. The numerical results reflects that on taking the higher order correction terms into account, the amplitude of the dressed soliton solution increases however its width narrows. The present plasma model may be helpful in simulating the electron acoustic solitary behavior in the auroral regions and magnetospheric plasmas of earth.ThesisItem Open Access Cylindrical electron-acoustic solitary waves with hybrid Cairns-Tsallis distributed hot electrons(Punjab Agricultural University, Ludhiana, 2019) Harmanpreet Kaur; Parveen BalaThe propagation of cylindrical electron acoustic solitary waves in a plasma system constituting cold electron fluid, immobile ions and hot electrons has been studied. The hot electrons are assumed to follow hybrid nonthermal-nonextensive distribution popularly known as Cairns-Tsallis distribution. This distribution is applicable within the parameters range 0.6 q 1 and 0 0.25. Using Reductive preturbation method Korteweg de- Vries (KdV) is derived to obtain the required solution for cylindrical electron acoustic solitary waves. Our present investigation focuses on revealing the dependency of the behavior of these waves on nonthermal parameter ( ) , hot-to-cold electron density ratio ( ) and nonextensive parameter ( q ). Only negative potential structures are reported in our plasma model. The effect of nonextensivity (q), nonthermality ( ) and cylindrical geometry on the amplitudes and width of electron acoustic potential structures have been studied numerically. The numerical results are presented in the form of graphs in given parametric ranges. The present plasma model may be helpful in simulating the electron acoustic solitary behavior in the auroral regions and magnetospheric plasmas of earth.ThesisItem Open Access Electron-acoustic double layers featuring cairns-tsallis distribution of electrons(Punjab Agricultural University, Ludhiana, 2019) Arshpreet Kaur; Parveen BalaPlasma is an ionized gas that can be considered as collection of positive and negative charge carriers and has net zero charge. It exihibits various striking nonlinear structures such as solitons and double layers. The nonlinear dynamics of large amplitude electron acoustic double layers in an unmagnetized collisionless plasma consisting of cold and hot electrons has been studied. The electrons are assumed to follows the cairns-tsallis distribution. Sagdeev pseudopotential method has been used to investigate the occurance of large amplitude double layers, focusing on how their characteristics depends upon the different parameters. For the selected range of parameters, it is found that only compressive double layers can exist. Further, the analysis is extended for small amplitude double layer solution by expanding the Sagdeev potential in the weakly coupled plasma limit ( <<1). The upper limits of the Mach number for the existence of double layer are dertermined, and their values are significantly modified in the presence of Cairns-Tsallis distributed electrons. Polarity of the nonlinear structures strongly depends on the nonthermal parameter ( ) and nonextensivity (q) of electrons. Depending on the nature of these double layers, their associated electric fields are thought to be responsible for particle acceleration or deceleration.
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