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ThesisItem Open Access Study of electrical and magnetic properties of cobalt based metallic glasses and composite material(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2005-07) Agrawal, Rati; Kushwaha, R.P.S.There are many materials of commercial importance; composite materials and metallic glasses are two such important materials among them. Wide variety of technological and industrial applications of these materials motivates the present work. Cobalt based metallic glass of nominal composition Co60B12Si12Fe4Mo2Ni1 and cobalt based composite material prepared by varying concentration of cobalt metal powder in plaster of paris was used for investigating their electrical and magnetic properties. For cobalt based composite material change in A.C. magnetic susceptibility with both frequency and concentration have been taken into account. Similarly temperature and concentration dependence of electrical resistivity of composite material was investigated. From experimental results obtained, A.C. magnetic susceptibility was found to decrease with frequency for all concentrations and increase in susceptibility was observed when plotted with concentration. when electrical resistivity of cobalt based composite material was investigate for its temperature dependence, slight decrease in resistivity or a dip was observed for all the concentrations i.e. for all the samples with different concentrations of cobalt metal powder in plaster of paris. Energy losses in the samples were also measured by studying their hysteresis loops for two different frequencies.ThesisItem Open Access Study of the role of pair transfer processes on isotope effect in superconducting TTF[Ni(dmit)2]2 systems(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2004-06) Pant, Manju; AjayIn the present investigation, we have studied the role of interband pair transfer processes on isotope effect in layered TTF[Ni(dmit)2]2 systems. For this purpose we have considered two chain Hubbard model that includes the intra and intermolecular vibrations in the presence of electron Coulomb energy and the electron transfer energy between the chains. Such a model calculations will be applicable for the organic superconductors where molecular layered structures are available. We obtained the expressions for the superconducting order parameter, transition temperature and finally the isotope effect coefficient ( ) using double time Greens’s function equations of motion technique within BCS mean field approximation. Finally the numerical analysis show that isotope effect coefficient ( ) depends on the intra and interlayer molecular vibrations, the pair transfer processes and also on the superconducting transition temperature (Tc) in layered organic superconductors like TTF[Ni(dmit)2]2 . On the basis of our model calculations we have predicted the effects of the pair transfer processes, the density of states at Fermi level and the chemical pressure on the isotope effect coefficient which need to be tested through rigorous experimental investigations on these systems.ThesisItem Open Access Determination of leaf water parameters of sarpgandha (Rauwolfia serpentina L.) plant using beta gauging technique(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2013-07) Tiwari, Bhoopendra Chandra; Joshi, G.C.The present study is concerned with the determination of the physiological parameters such as fresh leaf thickness and water content (actual and relative) of a medicinal herb Sarpgandha (Rauwolfia serpentina L.) leaves. We have measured the changes in these physiological parameters as a function of height of leaves from ground level. These parameters were calculated by beta gauging method by using 204Tl and 90Sr- 90Y beta sources of energy 0.77 MeV and 2.28 MeV respectively. The results were also compared with weighing method. The observations showed that the fresh leaf thickness decreased exponentially with the height of plant leaves from ground level. However, the actual water content and relative water content increased exponentially with the distance of leaves from ground level. The actual water content and the relative water content showed the linear relationship. The mass absorption coefficient ( ) was also determined by the beta gauging method and compared with the empirical relation. The observations showed that the mass absorption coefficient depend only on the end point energy of beta particle. The study further suggests that the beta gauging method is a rapid, effective, non-destructive and powerful tool to follow the changes in physiological parameters of plant leaves.ThesisItem Open Access Theoretical study of thermal expansion and bulk modulus of nanomaterials(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-07) Himanshi; Munish KumarA simple theoretical method is developed to study the effect of temperature on thermal properties viz. volume thermal expansion and bulk modulus of nanomaterials by modifying the He and Yan Model. We have considered seven nanomaterials viz. silver (20nm), aluminium (40), selenium (19nm), zirconia (8nm), zinc oxide (25nm), nickel oxide (25 nm) and titanium dioxide (35nm). The results are compared with the available experimental data for volume thermal expansion of nanomaterials. The good agreement between theoretical and experimental results supports the validity of the model. It should be reported that the experimental data of temperature dependence of bulk modulus are not available. So, we are reporting our computed results. Since our result depends on computed value of V/V0, which are in good agreement with experimental data. Thus the results of bulk modulus may be regarded as reliable. The effect of shape and size is also studied. We have considered the size 10nm and 90 nm to compute our results and observed that the volume thermal expansion decreases with the increasing size. We have also studied the effect of shape of nanomaterials on volume thermal expansion and bulk modulus. It has been observed that the value of V/V0 is maximum in case of spherical nanomaterial followed by nanowire and nanofilm.ThesisItem Open Access Study of quantum entanglement and Bell’s theory(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-07) Badhani, Kamal Kishore; Johri, U.C.ThesisItem Unknown Study of quantum entanglement and Bell’s theory(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-07) Pant, Kamal; Johri, U.C.ThesisItem Open Access Fluid flow calculations for perforated plate using ansys fluent®(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-06) Pant, Kamal; Agrawal, H.M.ThesisItem Open Access Study of molecular interaction in binary liquid mixtures (Toluene in propanol and butanol) using ultrasonic technique at different frequency(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-07) Agarwal, Shubhi; Joshi, G.C.ThesisItem Open Access Study of structural and optical properties of Barium Zerconate Titanate(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2016-06) Rawat, Pankaj Singh; Srivastava, R.C.