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ThesisItem Restricted EFFECT OF OHMIC HEATING ON THE ELECTRICAL CONDUCTIVITY OF GUAVA JUICE(Punjab Agricultural University, Ludhiana, 2013) Amanjot KaushalOhmic heating takes its name from Ohm’s law. The food material sandwiched between electrodes has a role of resistance in the circuit. In the present study, an ohmic heater was designed, fabricated and then used for performing the ohmic heating of different guava juice samples. The different samples of guava juice were prepared with five different concentrations of 50%, 60%, 70%, 80% and 90% by volume of the juice. The ohmic heating was performed at five different voltage gradients viz. 5.5 V/cm, 7.5 V/cm, 9.5 V/cm, 11.5 V/cm and 13.5 V/cm across the two ends of the designed ohmic cell. Different instruments and devices were used to measure the different properties of guava juice as a function of temperature at a regular interval of time during the ohmic heating. An Ostwald’s viscometer for viscosity, pH meter for pH and a hand refractometer for total soluble solid (TSS) were used. The electrical conductivity obtained as a result of ohmic heating was in the range 0.037 S/m to 0.326 S/m. The mathematical model using the linear regression analysis and one-way ANOVA using completely randomized design (CRD) led to the prediction of an equation of electrical conductivity. The linear equation was found to be highly accurate with R2 value in the range 0.173 to 0.999 showing the linear dependence of electrical conductivity upon the temperature. The viscosity, pH and the TSS was found to vary from 1.66 cP to 14.83 cP, 1.83 to 5.29 and 5.2°B to 12.2°B respectively. The voltage gradient was statistically significant (p < 0.05) on the heating times.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 Measurement of Attenuation Coefficient of Eucalyptus and Pinus roxburghii using gamma source(Punjab Agricultural University, Ludhiana, 2014) Thukral, Gunjan; Rajeev KumarMoisture content of composite materials like wood is a function of atmospheric conditions and depends on the relative humidity and temperature of the surrounding air. As a result of which the moisture content of wood is almost always undergoing some changes as temperature and humidity conditions vary. The variation in the moisture content is different in different types of wood and is known to affect the physical as well as mechanical properties of wood. Gamma ray transmission methods have been used to determine the mass attenuation coefficients of Eucalyptus and Pinus roxburghii wood samples at wet and oven dried states using a NaI(Tl) scintillation detector and a radioactive gamma source 137Cs. The measured mass attenuation coefficients were plotted against the relative moisture content of the wood samples and a linear behaviour was observed indicating that the attenuation decreases with the increasing moisture content, i.e., mass attenuation coefficient is least for completely wet samples and is highest for the oven dried samples. Also, the least square fitting of the data provides correlation coefficients whose values lie in between -0.995 to -1.000 in all the cases studied and are significant (p < 0.01). The high value of negative correlation indicates that attenuation is dependent on the thickness of the samples only.ThesisItem Restricted Determination of water status of selected fruit leaves using beta attenuation(Punjab Agricultural University, Ludhiana, 2016) Sood, Chetna; Paramjit SinghThe present study deals with the determination of mass attenuation coefficient and water content of fruit leaves of Guava, Papaya and Kinnow using beta transmission method. The radioisotopes 204Tl and 60Co with end point energies 0.777 MeV and 0.319 MeV respectively are used as beta emitters. The Geiger Muller Counter is used as detector for the measurement of beta attenuation for leaf samples. The slope of fitted line for leaf thickness versus logarithm of relative transmission intensity provides the attenuation coefficient. The measured value of mass attenuation coefficient agrees well with that calculated from statistical regression method. Also, the percentage water content values are determined using beta attenuation and found to be in close agreement with direct weighing. The water content of fruit leaves is varied using infrared radiation and the transmitted intensity is found to increase with decrease in water content of leaves. For all the fitted curves, the adjusted R2 lies in the range of 0.96 to 0.98 thereby justifying the linear dependence of transmitted intensity on water content, which is significant (p < 0.001). The beta attenuation method is nondestructive, easy to handle and can be done on intact planted leaves.ThesisItem Restricted Nonlinear Wave Structures in Dusty Plasma Using Extended Hyperbolic Tangent Method(Punjab Agricultural University, Ludhiana, 2016) Avneet Kaur; Paramjit SinghAn unmagnetised, collisionless plasma consisting of warm ion and cold, massive and charged dust grain is considered in which electrons are taken as Tsallis distributed. Korteweg-de-Vries (KdV) equation, in which both ion dynamics and dust dynamics has been considered to describe the evolution of nonlinear dust-ion acoustic waves, is deduced for dusty plasma system. KdV equation is derived with the help of reductive perturbation technique. In order to determine the exact solution of KdV equation, an extended hyperbolic tangent method is applied which deals with construction of travelling wave solutions. Six different cases of wave solutions are obtained for which dynamics of both slow and fast modes are studied. These travelling wave solutions are obtained with the aid of symbolic computation system which may be important for understanding the dust-ion acoustic solitary waves and shocks in space and laboratory plasma.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.