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ThesisItem Open Access Size and shape dependent thermodynamic study of nanometals(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-07) Uniyal, Shalini; Joshi, Deepika P.Thermodynamics of nanometals has became a great area of research due to their wide range of applications in many field of science. In the present work four different models i.e. Qi’s model, Qi-Wang’s model, Jiang’s model and Lu’s model have been used to study size and shape dependent melting temperature, Debye temperature and specific heat of Nanometals. These thermodynamic properties are calculated for different sizes and shapes like spherical, regular tetrahedral, regular hexahedral and regular octahedral. Sn, Pb, Bi, In, Cd, Al, Au, and Ag nanometals are taken for the study of size and shape dependent melting temperature, the size and shape dependent study of Debye temperature is done for Au, Fe, Sn and Co nanometals. Ag and Au nanometals are used for the study of specific heat. The calculated results obtained from these models are compared graphically with available experimental and simulated data.For melting temperature, the results obtained from the equation given by Qi-Wang’s model (for D<15nm) and Qi’s model ( for D>15nm) are found closest to available experimental and simulated data. Jiang’s model is found to be most suitable for the study of Debye temperature of nanometals. For the study of size and shape dependent specific heat, modified specific heat relation of Qi’s model gives better result. Present study reveals that the thermodynamic properties of nanometals are not only size dependent but also varies with shape for small sized nanoparticles. The shape of nanometals for particular size can also be predicted with the help of this study. The shape factor is found to be more pronounced at lower sizes while its effect becomes negligible for higher sizes.ThesisItem Open Access Calculation of (p,n) & (n,p) reaction cross-sections based on TALYS-1.6 for the production of medical radioisotopes(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-07) Dasila, Raj Kumar Singh; Joshi, G.C.The cross-section (excitation functions) of neutron and proton threshold reactions has gained considerable importance for the production of Therapeutic radioisotopes in the present era. The present study based on TALYS 1.6 code to calculate the cross section theoretically. This code has been used to evaluate (n,p) & (p,n)reaction crosssections for the production of therapeutic radioisotopes (64Cu, 64Ni, 67Cu, 89Sr, 90Y, 124I, 125I, 153Sm, 169Y, 186Re, 192Ir) for which a very few experimental data are available in EXFOR but some are discrepant. These theoretical calculations have been performed within the frame work of the level density parameter with pre-equilibrium effects using recent TALYS 1.6 code from the energy range threshold to 20 MeV. Before running the code optimization of input parameter (level density formulation) has also been done. The obtained results have been compared with EXFOR data and various available data files (ENDF, IAEA and TENDL) along with the experimental data available in the literature. It is concluded that computed results using TALYS 1.6 code is compatible with the experimental data from the literature.ThesisItem Open Access Effect of size dependent bulk modules on compression of nanomaterials(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-07) Belwal, Deeksha; Joshi, Deepika P.High pressure study is very important for better understanding of matter in the world around us and to create entirely new form of matter. In the present thesis, a theoretical study of the effect of size dependent bulk modulus on compression of nanomaterial has been done. Murnaghan, Birch-Murnaghan, Usual tait and Shanker equations of state are modified to include the effect of size on compression of nanomaterials. Then the applicability of these modified equations has been checked for Al2O3 (37 nm and 67 nm), Ge (13 nm and 49 nm), SnO2 (3 nm, 8 nm and14 nm), Ni (20 nm and 29 nm), PbS (2.6 nm, 5.4 nm and 8.8 nm) nanomaterials. These four equations are modified by considering linear and non-linear relation between size of nanomaterial and bulk modulus respectively, to investigate compresional behaviour of above nanomaterials. In both cases the results are compared with available experimental data. Present study reveals that modified equations which include linear relation between bulk modulus and size of nanoparticle are not valid for all chosen nanomaterials, while modified equations which include the non-linear relation between bulk modulus and size of nanoparticle are in good agreement with experimental data for all above nanomaterials. Shanker equation gives slightly different results from experimental results at high pressure. It is concluded that the general relation between bulk modulus and size of nanoparticle is not linear. Value of non-linearity parameter ϵ can be useful to understand behaviour of small particles. The non-linear size dependent modified equations of Murnaghan, Birch-Murnaghan, Usual Tait and Shanker may be helpful for compressional study nanomaterials.ThesisItem Open Access Study of quantum error correction and fault tolerant quantum computing(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-07) Mehta, Saurabh; Johri, U.C.ThesisItem Open Access Multi-elemental analysis of two varieties of tulsi using EDXRF and AAS(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-07) Bhandari, Deepak Singh; Joshi, G.C.Nowadays many medicinal plants are isolated and analysed for their medicinal properties and healing components by the researchers. Tulsi and its varieties (Rama and Shyama Tulsi) are a very important plant in the traditional medicinal system. The aim of this work was to analyse elemental content in different parts viz. leaves, stem, and roots of two varieties of Tulsi. Energy Dispersive X-Ray Florescence (EDXRF) technique was used to analyse samples of different parts of Tulsi. Ten elements viz. Mg, P, S, Cl, K, Ca, Mn, Fe, Cu, and Zn were identified and their concentrations were determined. We have also used Atomic Absorption Spectroscopy (AAS) to determine the concentration of four elements Mn, Fe, Cu, and Zn in various plant samples and found almost similar results as by EDXRF technique. Both varieties of Tulsi were found to be rich in the elemental content in the leaves and roots. Translocation of various elements in different parts of the plants and their biological importance for human body were discussed in brief. A comparative study of elements in leaves, stem, and roots between two varieties of Tulsi was established, and it was observed that Rama Tulsi was found richer in elemental content than Shyama Tulsi. No toxic element was detected in the both varieties of Tulsi which proves that it suitable for the medicinal use. This plant attracts a special attraction as a source of iron, especially for humans with low iron intake and for the people with low level of haemoglobin. The results of the present study provide justification for the use of Tulsi and its varieties in the treatment of several diseases since they contain a wide range of macro and micro elements in all its parts which are vital to human health. This analysis may be useful in the exploration of the medicinal importance of these two varieties of Tulsi.ThesisItem Open Access Study for the effect of size on compression for different shape of nanomaterials(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-07) Tamta, Pramesh; Munish KumarThesisItem Open Access Fission cross-sections of important actinides produced in the TH-U fuel cycle(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-07) Pandey, Hem Chandra; Agarwal, H.M.Accurate measurement of neutron induced fission cross-section data are essential in designing the future fission reactors. In the present work, neutron induced fission cross-sections are calculated for different isotopes of Thorium, Protactinium and Uranium (232Th, 231,232,233Pa, 232,233,234,235,236U) which produces in the Th – U fuel cycle. The calculations were done with EMPIRE 3.1 Nuclear code, which is based on various theoretical model and number of FORTRAN codes, reference input parameter libraries (RIPL) and experimental data library (EXFOR). The comparison of (n, f) reaction cross-sections calculated using the barrier parameters obtained by the analytical barrier formula are more reliable and supported by the experimental and evaluated results. The fission barrier height values of various radionuclides, taken from RIPL-1, RIPL-2 and RIPL-3 produces the experimental and evaluated data poorly for the studied actinides. Thus, it is concluded from the results of the present work that the precise measurement of the barrier heights is very important to predict the fission cross-section data accurately.ThesisItem Open Access Simulation study of ion irradiation on carbon allotropes and their ferrite composites(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-07) Sah, Dheeraj; Srivastava, R.C.ThesisItem Open Access Study of quantum cryptography(G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2017-06) Gautam, Abhay; Johri, U.C.