Department of Physics
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Item Study of Streaming Dust Acoustic Instability in Quantum Plasma(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2018) Asif Zahoor; FA16-RPH-031; Dr. Muhammad Jamil; LHR TP 5240In this thesis a study related to Streaming Dust Acoustic Instability in Quantum Plasma is done. In this investigation starting from equation of motion containing Fermi Pressure, Bohm Potential and Exchange Correlation term we use quantum hydrodynamic (QHD) model to derive a general expression for dielectric constant which led to the final dispersion relation. A graphical discussion is also made by considering real part which shows the phase speed of DAWs whereas the imaginary part give the growth rate. The graphical results are obtained by varying the mass of dust particles, number density of electrons and by taking different streaming speed. This research is expecting a great scope in astrophysical quantum plasmasItem Study of Dust Acoustic Waves with Dust Charge Fluctuation in Quantum Plasm(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2018) Rubina; FA16-RPH-016; Dr. Muhammad Jamil; LHR TP 5230In this dissertation, the time-dependent charge fluctuation of dust particles have been studied in quantum dusty plasmas. The dust acoustic wave has been taken as the perturbation of the plasma system. The quantum fluid model consisting upon momentum balance equation, continuity equation and gravitational Poisson’s equation has been employed to solve for the dispersion relation. The instability of the wave in the form of damping is observed. It is noticed that the dust acoustic wave went to damp for the whole spectrum of k on varying ion-thermal temperature, electron number density and dust radii.Item Synthesis of Silver Nano Particles with Arabic gum via Hydrothermal Method(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2020) Laiba Hussain; FA16-BPH-004; Dr. Akbar Ali; LHR TP 5922Finely divided silver nanoparticles were synthesized via hydrothermal method. Arabic gum was used as reductant and steric-stabilizer both without any other material. Nano particles less than 100 nm have made an excellent impact in biomedical applications like diagnostic and medical devices for personalized health care particles. Silver nano particles with various characteristics can be-obtained by adjusting the reaction temperature, mass ratio of Arabic gum and silver nitrate. Sample products were characterized by FTIR, SEM and X-RD measurements. It was noticed that temperature and Arabic Gum played an important role in the synthesis-of silver nano particles. Well dispersed and fine form of silver nano particles were obtained under the conditions of 0.5 mmol/L AgNo3 m(Ag)/m(AgNo3)=1:1, 160 0C for 3hrs. We discussed the chemical cytoxicity and Plasmonic properties of nano particles and also the current application of AgNps.Item Salt-Water Batteries as anAlternative Energy Source(2020) Zahra Munir , Faiza Riaz; FA16-BPH-033 , FA16-BPH-080; Dr. Mukhtar Ahmad; LHR TP 5926The Energy-sector plays a vital role in ensuring all-round development and growth of economy of a nation. Pakistan, despite the enormous potential of its energy resources, remains energy- deficient and must rely heavily on imports to satisfy its needs.This project is to find the best solution of salt-water as an electrolyte in battery cell for power generation. In order to generate a power source, the method of electrolysis was applied by using Iron and Copper as the negative and positive terminals respectively, the solution of salt-water as an electrolyte and Copper (II) sulphate (CuSO 4) as an additive. There were three conditions of experiment that were carried out;i) changing size of Iron strips and Copper strips, ii) changing volume of salt-water, iii) different amount of Copper (II) sulphate (CuSO 4). In the first condition, the result showed that the bigger the size of Copper strips, the higher the current value produced. While in the second condition, there was not much effect produced in current and voltage values. In the third condition, the addition of CuSO 4 gave a large positive impact on the power cell. Judging by this experiment, it is decided to inject some amount of CuSO4 in the electrolysis. The main reason of injecting CuSO 4 into the electrolysis was to boost up the current value. Thus, the results showed that the combination of abundant amount of salt-water with limited amount of Copper (II) sulphate solution (CuSO 4) was a viable alternative source for future power cell generation.Item Synthesis And Characterization Of SrFeO3 Nanoparticles by Co-precipitation Method(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2020) Usama Zahid , Muhammad Ikram; FA16-BPH-065 , FA16-BPH-023; Dr. Akbar Ali; LHR TP 5936In the past decade, magnetic nanoparticles have much attention due to their properties and technological applications. Strontium ferrite (SrFeO3) particles were prepared by co-precipitation method. The ferrite precursors have produced from aqueous mixtures of iron nitrate and strontium nitrate by co-precipitation, using potassium hydroxide aqueous solutions as precipitant. As above synthesis of strontium ferrite nanoparticles has prepared by co-precipitation method using iron nitrate and strontium nitrate and potassium hydroxide at different temperatures. The synthesis is characterizing by X-Ray Diffraction and Fourier Transform Infrared Spectroscopy. The x-ray points out the being formed SrFeO3 structure. Fourier transforms infrared spectroscopy point out functional group of particles and absorption related to metal oxygen vibration modes. This co-precipitation method allows a large-scale production of SrFeO3nanoparticles easily. The powder looks brownish.Item Development Of Cobalt Disulfide Through Microwave(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2020) Soha Iqbal , Anam Pervez; FA16-BPH-013 , FA16-BPH-015; Dr. Aamir Razaq; LHR TP 5935Global warming is a major issue in a modern era due to greenhouse gases. Fossil fuel energy creates serious environmental, economic and resource deficiency problems. Such sources which generate and store electrical energy with the benefit of free, economical and biodegradable greenhouse gases are needed. With the development of nanotechnology, the modern world is shifting from old sources of energy to more efficient and sustainable sources of energy. In this research work, super capacitors electrodes are produced using a composite of CoS2 and natural fiber with improved power and energy density. The powder of CoS2 is prepared through microwave assisted method. The structural properties of cobalt disulfide are analyzed by XRD, SEM, FTIR, and cyclic voltammetry. Octahedron-shaped CoS2 crystals have been successfully fabricated through a simple hydrothermal route without any surfactant or template. The well- defined octahedral structures are highly uniform with a mean edge length of ~ 360 nm and exhibit a high geometric symmetry. The mechanism for the evolution process of the final octahedral structures is researched and proposed to begin with a growth and self-aggregation process. When electrochemically investigated as electrode materials for super capacitors, the as- fabricated CoS2 electrode shows typical pseudocapative properties with a specific capacitance of 236.5 F g-1 at 1 A g-1. Remarkably, it exhibits an excellent cycling stability at 2 A g-1 with only a loss of 7.4% in the specific capacitance after 2000 cycles.Item Di-electric and Band gap characterized of Indigenously Collected natural fibers.(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2020) FAZEELA BASHARAT , MUHAMMAD UZAIR SHAFIQ; FA16-BPH-070 , FA16-BPH-019; Dr. Aamir Razaq; LHR TP 5933Due to increase in demand for energy storage in today’s society, the development of inexpensive, flexible and light weight energy storage device is essential. In this respect, paper-based energy storage devices are highly being preferred. The aim of this thesis to evaluate the use of Banana, Papaya and Q2 source. Banana, Papaya and Q2 source are used for paper-based energy storage devices. We report the band gap and dielectric properties of indigenously collected natural fibers, by having the sources of Banana, Papaya and Q2 source. By making the sheets of the sources with 0%, 15%, 30% and 45% bleaching. Afterwards, their characterization Impedance, bending effect, energy storage capacity, dielectric properties are observed by having the equal weight of the entire sheets. Dielectric properties increased when we increased the fiber content because the no. of polar groups increased. Di-electric constant, dissipation factor, di-electric loss factor of natural fibers was high at low frequency. Di-electric values decreased when frequency increased for all hybrid composites. Photonic band gap fibers are similar to electron wave motion which is analyzed by Bloch formulation. Effect of design parameters are also observed in terms of variations of allowed and forbidden bands of band gap fibers. I concluded that banana is the best source in terms of flexibility for energy storage applications.Item Isolation of lignin/cellulose Fibers from Self growing Plants from Indigenous sources(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2020) Marwa , Samia Akhtar , Sidra Naz; FA16-BPH-030 , FA16-BPH-031 , FA16-BPH-029; Dr. Amir Razaq; LHR TP 5930Due to increase in demand for energy storage in today’s society, the development of inexpensive, flexible and light weight energy storage device is essential. In this respect, paper-based energy storage devices are highly being preferred. In this work, we report the fabrication and performance of super capacitors made from carbonized peanut shells and sugarcane which are renewable materials with a huge annual yield and are usually discarded directly by people. With proper treatment, peanut shells could be used for many applications. The aim of this thesis to evaluate the use of peanut shell flour and crushed wasted sugarcane cellulose fibers and conductive polymers i.e. polyaniline and polypyrene are used for paper-based energy storage devices. Two conductive composite paper materials were developed by covering the individual lignocelluloses fibers obtained from the peanut shells and sugarcane plant with a conducting polymer (Polyaniline, polypyrrole) coating.Item DFT study of positive LiMnPO4 electrode material of Li-ion battery(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2020) Fakhar Abbas , Ammar Zamir; FA16-BPH-044 , FA15-BPH-077; Dr.JunaidAmjad; LHR TP 5934In this DFT calculations, diffusion of li ions in LiMnPO4 has been studied by using first principle and harmonic transition state theory. We have calculated the diffusion barrier and forward and reverse diffusion rates for diffusion mechanism in LiMnPO4. The results were in agreement with the literature value. Further improvement can be done by changing the exchange correlation potential and geometry optimization parameters while performing DFT calculations. Current work can be modified by using the doped LiMnPO4 material with transition metalsItem Solar Oven/ Cooker(Library Information Services, COMSATS University Islamabad, Lahore Campus, 2020) Aqsa Azam , Misbah Amjad; FA16-BPH-067 , FA16-BPH-068; Dr. Shahzada Qamar Hussain; LHR TP 5928Solar cooking technology is a global response to poverty and the humiliation of climate, but very little work is conducted into the effect of using solar ovens on biomass fuel consumption. We design a solar oven/ cooker. The solar oven/cooker highly dependent on sunlight. It can cook or fried various things decently. This study evaluates the use of solar ovens and wood consumption in both rainy and dry seasons in northern Nicaragua, using surveys, temperature data loggers, and direct fuel wood use measurement. Owners of solar ovens recorded 79 percent use during the dry season and 41 percent of days during the rainy season. Oven temperature records recorded use during the dry season for 50 percent of days, and 16 percent of days during the rainy season. However, wood consumption measurements showed no statistically significant differences between days with solar furnace use and days without, suggesting that the frequency of use alone is not an appropriate proxy for fuel savings. Results of the survey suggest that, as opposed to replacing it, a large part of the use of solar furnaces came in addition to the cooking of biomass. These results suggest a need to further study the consumption of wood in situ and focus more on the specific types of foods prepared in solar cookers, as well as local cultural and climate conditions.