Loading...
Thesis
Browse
35 results
Search Results
ThesisItem Embargo 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 Embargo Effect of rice syrup adulterant on dielectric properties of honey(Punjab Agricultural University, Ludhiana, 2023) Rashneet Kaur; Rajeev KumarHoney is natural complex food product produced by bees from nectar of plants and also from honeydew. It is a unique sweetening agent that can be used by humans without processing. The honey composition depends on geographical location of where the honey is found. Commonly the quality of honey is measured by sensory and chemical analysis. This type of measurement can be very expensive with a complicated procedure. In present work, the dielectric, electrical, physiochemical and rheological properties of multifloral honey adulterated with rice syrup has been investigated using a non-destructive measurement technique. The objective of this research is to access these properties at frequency range (10 kHz-100 kHz) and temperature range of (20°C-80°C). Honey was adulterated at five different concentrations (10%, 20%, 30%, 40% and 50%). Dielectric constant was found to decrease linearly with the increase in temperature, frequency and adulteration. Loss tangent increased linearly with increase in temperature and decreased linearly with increase in frequency. Electrical conductivity increased linearly with the increase in temperature and frequency. Both loss tangent and electrical conductivity increased linearly with increase in adulteration. The viscosity decreased exponentially with temperature, whereas the density decreased linearly with temperature. The ultrasonic velocity was observed to decrease as the temperature increased from 20°C to 80°C. Acoustic impedance, bulk modulus and surface tension were observed to decrease linearly as the temperature was increased. The variation in dielectric constant (electrical conductivity) with frequency (10 kHz-100 kHz) was 56.34-37.13 (0.230.36) for pure honey and changes to 39.93-32.13 for 50% adulteration of honey with rice syrup and electrical conductivity increased to 1.45-1.61 for 50% adulteration of honey with rice syrup. The Bulk modulus for pure honey was 58.73 – 51.54 and decreased to 51.61-41.26 in the temperature range of 20°C-80°C. The data obtained was statistically analyzed using one-way analysis of variance at 5% level of significance. These parameters were found to vary significantly with adulteration.ThesisItem Open Access Toy Monte Carlo and Background Studies for Decay of Neutral B-meson to Charmonium and Gamma(Punjab Agricultural University, Ludhiana, 2021) Bahl, Ishnoor Kaur; Sharma, Rajeev KumarThe research is based on the study of the rare radiative decay of 𝐵0 → 𝐽/𝜓𝛾 using data collected (corresponding to 772 million 𝐵𝐵̅ pairs) by the Belle detector at ϒ(4S) resonance with a Lorentz boost of 0.425 at asymmetric 𝑒−𝑒+ collider at KEK, Japan. This rare decay of B mesons is a sensitive probe of New Physics outside the Standard Model as there is a possibility of (V+A) charged current admixture to the standard (V-A) current. The branching ratio measurement of this rare decay will help to test the validity of various QCD models. In radiative annihilation decay, 𝐵0 → 𝐽/𝜓𝛾, the dominant mechanism is the exchange of W bosons and the radiation of a photon from light quark of B mesons. The decay of 𝐵0 → 𝐽/𝜓𝛾 ( 𝐽/𝜓 → 𝑒−𝑒+/𝜇−𝜇+) and the reconstruction of 𝐵0 mesons is a valid test for the measurement of time-dependent CP violating asymmetries. A signal Monte Carlo 100,000 events were generated by EvtGen to calculate the signal reconstruction efficiency by 3dimensional fit to 𝛥𝐸, 𝑀𝑏𝑐 and helicity (cosθ), which is 33.9 ± 0.19%. A large number of Toy Monte Carlo samples were generated to check the validity of the fit hypothesis and to find any possible bias in the final fitter. The toyMC study was performed for signal and background separately as well as both together. The yield for signal + background toyMC, determined from unbinned likelihood fit for generated toy samples, is 47.87 ± 0.36 which is consistent with the generated 47 events. The agreement of mean and sigma of pull distribution with zero and unity implies that there is no significant bias in the fitter developed for the decay modeThesisItem 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 Open Access Propagation characteristics of rogue waves in multicomponent plasma using kaniadakis distribution(Punjab Agricultural University, Ludhiana, 2021) Gurleen Kaur; Parveen BalaMany studies have shown that space plasmas is of multi-component type, including positive and negative ions that exist in the D zone of the ionosphere. In the present study, we analyzed the growth rate for Modulational instability (MI) and rogue waves (RWs) for both slow and fast modes in multicomponent unmagnetized plasma viz. H+H-, Ar+F-, and H+O2- plasma systems at different temperatures of positive and negative ions. The non-Maxwellian distribution known as κ-deformed kaniadakis distribution has been applied to the electrons in the range of deformation parameter κ, -0.4≤κ ≤0.4. The Nonlinear Schrodinger equation has been derived by using the standard Reductive Perturbation Method. It is observed that deformation parameter κ influences the properties of RWs in both slow and fast modes. The obtained results are examined by deviating the different parameters such as deformation parameter κ, the temperature of positive and negative ions (σ1, σ2), mass ratio η, density ratio α, and modulational wave number KMI. The present research may be useful in understanding the study of astronomical physics, non-linear waves of plasma.ThesisItem Open Access 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 Open Access 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 Mass attenuation coefficient and water content determination of Jamun (syzygium cumini) and Sal (shorea robusta) wood using gamma radiation(Punjab Agricultural University, Ludhiana, 2021) Charanjeet Kaur; Sharma, Rajeev K.Water content in wood is the major parameter for deciding the strength, quality and durability of wood. The water content of wood was determined by calculating its mass attenuation coefficient at various moisture intervals. The mass attenuation coefficient of Jamun and Sal wood samples have been measured using gamma ray spectrometry based on NaI(Tl) scintillation detector at gamma ray energy of 662 keV from radioactive source 137Cs. The semi-logarithmic plots of relative transmission intensity versus thickness were plotted for completely wet and oven-dried wood samples. The mass attenuation coefficient is obtained from the slope of these curves which is further employed to estimate the water content in wood. The mass attenuation coefficient of Jamun wood at fully wet and oven-dried state was found to be 61.9±21.7 cm2/kg and 93.7±18.9 cm2/kg respectively. Also, mass attenuation coefficient of Sal wood at fully wet and oven-dried state was found to be 52.5±16.8 cm2/kg and 86.1±24.5 cm2/kg respectively. The plot of mass attenuation coefficient against the relative water content shows that mass attenuation coefficient increases linearly with decreasing water content. The variation of water in wood have been studied by placing wood sample in water up to half of its thickness for different time intervals. The calculated moisture gradient curves follow the exponential decay law. These studies may also help to better understand the internal stress and dimensionality or dimensional stability of wood at different water levels. The determination of water content of Jamun and Sal wood using gamma radiations is rapid, more accurate and can be made non-destructive by properly simulating the prototype of this experiment with suitable Monte Carlo simulation in field practices.
