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ThesisItem Embargo Synthesis and characterization of graphene and modified graphene-based polymer nanocomposites(Punjab Agricultural University, Ludhiana, 2023) Ramandeep Kaur; Kiran JeetSynthesis of nanomaterials from chemical precursors is not only expensive but also releases carcinogenic toxic chemicals during the reaction. In this study, the graphene oxide (GO) and nanocellulose (NC) were fabricated from agri-waste. The nanomaterials synthesized from agricultural precursors were compared with the similar nanomaterials prepared from conventional precursors. Their structures and chemical composition were compared with high resolution imaging and spectroscopic tools. The study has also undertaken the production of nanocomposites of these materials. Recycling of agricultural waste due to its abundance is considered to be the biggest challenge. As burning of agri-waste causes serious environmental and health related issues. Hence, utilization of agricultural waste in synthesizing nanomaterials helps in their recycling and minimizes environmental impact with an added advantage of circular bioeconomy. Keeping this in view, GO was prepared using rice husk ash and NC was extracted from sugarcane bagasse along with their nanocomposites. The nanocomposites prepared using agricultural waste sources and conventional sources were inspected by N2 adsorption-desorption analysis, which demonstrated that the nanocomposites prepared from agri-waste sources exhibits much higher specific surface area than that of prepared from conventional precursors.ThesisItem Open Access Study of inclusive production of charmonium mesons in B decays(Punjab Agricultural University, 2013) Nitika Goyal; rajeev kumarCharmonium is a heavy meson containing a charm and anti-charm quark. Studies of charmonium production has improved our understanding of heavy quark production and formulation of bound states of quark pairs. Prompt charmonium production provides an interesting environment to study the interplay between perturbative QCD and non-perturbative effects. Non-relativistic QCD (NRQCD) provides a consistent calculational framework for direct heavy quarkonium production. The inclusive production of charmonium meson is studied using a data sample corresponding to 386 million events which has been collected at upsilon (4S) resonance (bound state of quarks) with the Belle detector at the KEKB asymmetric energy collider. Events are required to pass through tight event selection criteria. candidates are reconstructed using the leptonic decays . A large Monte Carlo sample has been used to determine signal reconstruction efficiency and parametrization of background. The measured branching fraction for inclusive B= (1.10 0.005) % and B)X = (1.09 %. The feeddown contribution from ( and B X has been taken into account and corrected branching fraction is (0.77 %.ThesisItem Open Access Ultrasonic studies of honey at different moisture content and temperatures(Punjab Agricultural University, Ludhiana, 2016) Gurpreet Kaur; Paramjit SinghThe composition of natural honey present in the world is different and India too produces honey from various floral sources with wide variations in physicochemical and rheological characteristics. From, last decades honey has been a prime target of adulteration for economic gain. These artificial honey which can be made poorer in quality by adding amounts of sucrose, commercial glucose, water and other substances, often have similar taste and physical appearance as natural honey, but they lack the medicinal and nutritional properties of natural honeys. Detection of adulteration in honey is difficult, but some physicochemical properties of honey that can be easily determined which is helpful for comparison of different honey. Ultrasound is a versatile non-destructive technique and used in the food industry in both for the analysis and modification of foods. In the present study, the physicochemical properties including ultrasonic velocity, density, electrical conductivity and total soluble solids (TDS) in honey was investigated at different temperatures (20,30,40,50,60 and 70°C) and concentrations (100, 90, 80, 70 and 60%) to have the idea of effect of water adulteration and effect of heat on these properties. The ultrasonic velocity was found with ultrasonic interferometer at frequency of 1 MHz and density is measured with specific gravity bottle method. The electrical conductivity and TDS in honey was recorded from digital conductivity and TDS meter. Some thermodynamics properties of honey like surface tension, adiabatic compressibility, acoustic impedance, bulk modulus and intermolecular free length was also calculated from the observed parameters which will provide a fundamental insight on its structural organization. All the observed parameters except density were significantly vary with the temperature and dilution. The ultrasonic velocity, density, surface tension, acoustic impedance and bulk modulus was found to be decreases with temperature and dilution of honey while electrical conductivity, TDS, adiabatic compressibility and intermolecular free length was increases with the applied conditions. A significant correlation was observed between electrical conductivity and TDS at all temperatures and concentrations.ThesisItem Open Access Mercury adsorption on functionalized carbon nanotubes(2016) Nupur; Kiran JeetHeavy metal contaminations possess serious threat to life and livelihood of people around the globe. Studies aimed to employ carbon based nanomaterials to decontaminate water from heavy metal ions of mercury. For this thiol functionalized carbon nanotubes (CNTs) were synthesized by first oxidizing the tubes and then reacting them further with thionyl chloride in a sequence. Then the successful functionalization of the CNTs was confirmed using Fourier Transform Infra-red (FT-IR) spectroscopy, Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM). Effect of different parameters like adsorbent dosage, contact time, pH and temperature on different adsorbents capacity to remove Hg(II) ions from solution was studied and a comparative data was collected. The thiol functionalized CNTs showed better adsorptions for Hg(II) ions as compared to carboxylic functionalized CNTs. Values of ∆Ho and ∆So were also calculated and found to be positive, indicates that adsorption of mercury ions on CNTs surface was an endothermic process. Then the maximum adsorption capacity was investigated for all the adsorbents using equilibrium isotherms, such as Langmuir and freundlich, the maximum adsorption capacity of SWCNTs-SH for Hg (II) ion removal was achieved at 111.12 mg/g and for MWCNT-SH it was 83.34 mg/g by fitting with Langmuir isotherm model.ThesisItem Restricted Reconstruction of charmonium ( ) using Belle detector(Punjab Agricultural University, 2014) Monica; Rajeev KumarCharmonium is a bound state of charm and anti-charm quark. The charmonium states are of great interest both from theoretical and experimental points of view because of their clear experimental signature and great simplification caused by their non-relativistic nature. The charmonium production involves physics at both perturbative and non-perturbative energy scales and provides one of the more manageable processes for QCD calculations. Precise measurements of the inclusive branching fractions for B meson decays to different charmonium states provide sensitive tests of these models. Measurements of B meson decays to charmonium are also important ingredients in the study of b-quark production in hadronic interactions. Reconstruction and study of charmonium mesons in B meson decays is a crucial component of the measurement of time-dependent CP violating asymmetries. Here, inclusive production of (which is reconstructed from its radiative decay mode → J/ ), using a data sample of 386 million events which have been collected at (4S) resonance (bound state of quarks) with Belle detector at KEKB asymmetric energy collider, is studied. A large Monte Carlo sample is used to determine the reconstruction efficiency and parameterization of background. The obtained branching fraction is B(B X) = (0.44 ± 0.01)%. The feed-down contribution from higher charmonium state ( → ) is taken into account and the direct branching fraction is B(B X) (direct) = (0.41 ± 0.01)%.ThesisItem Open Access Study of ohmic heating behaviour of mango juice(Punjab Agricultural University, Ludhiana, 2014) Dawar, Kanupriya; Paramjit SinghNew technologies for thermal processing of liquid foods are of great industrial and scientific interest. Ohmic heating is one of these new technologies. The present study aimed to design and built ohmic heating system. The ohmic system so developed showed adequate performance, and heating the product satisfactorily. Ohmic heating process is influenced by a number of factors such as electrical conductivity, viscosity, pH, solid content and electric field strength. The mango juice was heated on a laboratory scale static ohmic heater at different voltage gradients 7-27 V/cm. The voltage gradient was statistically significant on the ohmic heating rate for mango juice (P<0.05). Measurements were made from 14 to 70 °C and showed a linear fashion with electrical conductivity. The electrical conductivity of mango juice was in the range of 4-17 S/cm. The increase in the concentration of the juice from 50% to 90% enhanced the ohmic heating rate of mango juice. Other parameters- viscosity, pH and total soluble solids (TSS) were studied under ohmic heating. The viscosity of mango juice varied from 6.78 to 31.61 cP. Change so observed in the viscosity and pH of juice came out to be statistically significant for all the concentrations studied at different voltage gradients and (P<0.01). The pH of juice varied from 2.06 to 3.57. The TSS values recorded were in the range of 7.2 to 13.8 °Brix. The change in the TSS value of juice was statistically nonsignificant (p<0.05). The predictions of mathematical model using obtained electrical conductivity equation were found to be very accurate.ThesisItem Open Access The effect of magnetic field on viscosity and ultrasonic propagation in distilled water.(Punjab Agricultural University, Ludhiana, 2014) Sharma, Naresh; Paramjit SinghThe technology of magnetic water has been widely studied and adopted in the field of agriculture in many countries. The water passes through magnetic field is known as magnetized water. The clusters of water molecules are influenced by the magnetic field that affects the physical properties of water. Magnetized water has very useful effects in agriculture such as on seeds, yield, plant length and crop productivity. The main objective of this work is to investigate the effect of magnetic field on the viscosity and ultrasonic propagation velocity in distilled water in order to get insight of the changes in water structure. The viscosity and ultrasonic propagation velocity in distilled water were measured at the different strengths of magnetic field varying from 0.18 T to 0.40 T and 0.016 T to 0.128 T respectively. The changes in viscosity and ultrasonic propagation velocity in distilled water before and after the application of magnetic field were compared. During the experiment, it was observed that the viscosity of distilled water was decreased and the ultrasonic propagation velocity in distilled water was increased with magnetic treatment. The memory effect of magnetized distilled water was also observed when the magnetic field was removed. From the observed experimental data, it was concluded that the memory time of magnetized distilled water depends on the magnetic field strength. Statistical analysis which included Tukey’s test was performed and the results of viscosity and ultrasonic propagation velocity in distilled water were statistically significant (p<0.05).ThesisItem Open Access The effect of magnetic field on viscosity and ultrasonic propagation in distilled water(Punjab Agricultural University, Ludhiana, 2014) Sharma, Naresh; Paramjit SinghThe technology of magnetic water has been widely studied and adopted in the field of agriculture in many countries. The water passes through magnetic field is known as magnetized water. The clusters of water molecules are influenced by the magnetic field that affects the physical properties of water. Magnetized water has very useful effects in agriculture such as on seeds, yield, plant length and crop productivity. The main objective of this work is to investigate the effect of magnetic field on the viscosity and ultrasonic propagation velocity in distilled water in order to get insight of the changes in water structure. The viscosity and ultrasonic propagation velocity in distilled water were measured at the different strengths of magnetic field varying from 0.18 T to 0.40 T and 0.016 T to 0.128 T respectively. The changes in viscosity and ultrasonic propagation velocity in distilled water before and after the application of magnetic field were compared. During the experiment, it was observed that the viscosity of distilled water was decreased and the ultrasonic propagation velocity in distilled water was increased with magnetic treatment. The memory effect of magnetized distilled water was also observed when the magnetic field was removed. From the observed experimental data, it was concluded that the memory time of magnetized distilled water depends on the magnetic field strength. Statistical analysis which included Tukey’s test was performed and the results of viscosity and ultrasonic propagation velocity in distilled water were statistically significant (p<0.05).
