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A theoretical study of different zone formation in fermi bubbles
(UMT, Lahore, 2023) MUHAMMAD ARIF
Fermi bubbles are formed by the release of large amount of energy from the black holes by tidal disruption at the center of galaxy. We divide these fermi bubbles into different regions. These regions include strong gravitational potential zone, a cumulative zone of diffusive, non-diffusive, and thermal region. While the last one is quasi-thermal zone. We study energy transfer mechanism by the irregularities produced by magnetic fluctuations in these regions.
Design and implementation of a low-cost spin coater for thin film deposition
(UMT, Lahore, 2024) SAHA ZAINAB; SYEDA SAMREEN ZAIDI
The design and development of the economical and efficient spin coater is described in this paper. A spin coater deposits a film uniformly on the target material and can be made using information of various disciplines such as Electronics, Mechanics and Physics. The system is developed using a brushless motor along with an Arduino and ESC for accurate speed regulation making it simple and cost effective. An Arduino is used as a microcontroller to coordinate the coating process and communicate with the LED display and ESC. The spin coater has a speed range from 500rpm to 1500rpm, making it easy to develop different film thicknesses, which can be controlled depending on the material used. This spin coater, developed with easily accessible mechanical and electronic components, offers a user-friendly approach for achieving uniform thin films, making it appropriate for widespread use in academic and research settings
Design and implementation of IR sensor-based obstacle detector
(UMT, Lahore, 2023) Nasir Sultan
Designing and implementing an IR sensor-based obstacle detector involves several steps. Here's a general overview of the process: Determine the specific requirements of your obstacle detector, such as the detection range, sensitivity, response time, and power consumption. Choose a suitable IR sensor for your application. There are various types available, including reflective sensors, through-beam sensors, and proximity sensors. Consider factors like range, output type (analog or digital), and ambient light immunity. The circuitry required for interfacing the IR sensor with a microcontroller or other processing unit. The circuit typically includes components like resistors, capacitors, and voltage regulators. Consult the datasheet of your chosen sensor for specific design guidelines. Perform calibration to establish the sensor's baseline readings in the absence of obstacles. This step is essential for accurate obstacle detection. Calibration involves measuring the sensor's output in a controlled environment and using those readings as a reference for subsequent obstacle detection. Determine the optimal positioning and mounting of the IR sensor for effective obstacle detection. Consider factors like the sensor's field of view, desired detection range, and the type of obstacles you want to detect. Mount the sensor securely in the desired location. Capture and process the sensor's output signals using a microcontroller or a dedicated signal processing unit. The processing may involve amplification, noise filtering, and thresholding to convert the analog signal into a digital representation suitable for obstacle detection. IR based obstacle detector was designed and implemented and was found suitable for automated application.
Effect of concentration variation on zirconium nickel cobalt metal organic framework-based electrode material for supercapacitor applications
(UMT, Lahore, 2024) Taimoor Akbar
In this research, two samples of a ZrNiCo ZIF-67 with the change in molar concentration of metal to linker (1:1 and 1:2) were synthesized via the co-precipitation method. Then electrode fabrication was done. An attractive candidate for supercapacitor electrodes, ternary metal oxides ZIF 67 exhibit a number of desirable properties, including a large surface area, porosity, chemical stability, tailor ability, redox activity, and low environmental impact. The porous polyhedral structure of ZrNiCo ZIF-67, which incorporates connected nanoparticles of varied compositions, greatly enhances the charge storage capacity. They are essential to a robust and sustainable energy future, and they have social, ecological, and economic significance. Electrochemical methods such as cyclic voltammetry (CV), galvanostatic charge and discharge (GCD), and electrochemical impedance spectroscopy (EIS) are among the various characterizations used to assess the electrode's performance. Other approaches include X-ray diffraction to study the crystal structure. With a specific capacitance of 232 F/g at a current density of 1 A/g, the ZrNiCo ZIF-67 (1:2) electrode material performs better than the other ZrNiCo ZIF-67 (1:1) materials. In order to create nanocomposites ZrNiCo ZIF-67 (1:2) with improved electrochemical characteristics, this research provide an easy and practical method. These materials can then be used as electrodes in supercapacitors for high specific capacitance.
Enhancement of surface area and wettability properties of titanium by femtosecond laser induced periodic surface structuring
(UMT, Lahore, 2024) MUHAMMAD BIN AKRAM
Laser Surface Structuring (LSS) is a well-known technique used to alter the topological and tribological properties of solids, usually to make them more suitable for certain applications. Our aim was to use it on a titanium sample to make it more bio-compatible. We wanted to make our sample more osseointegral, so that it would show better results when placed inside a human body. Research shows that enhancing a substance’s wettability to make it more hydrophilic can produce improve desired qualities such as protein assimilation and cell adhesion. We had one sample of medical grade titanium (Ti6Al4V), which we used a Ti:Sapphire femtosecond laser on to alter its surface properties and wettability. Afterwards, it was observed using FESEM and the sessile drop method, which revealed enhancements in surface roughness and wettability.
Galactic outflows in different geometries
(UMT, Lahore, 2023) UZAIR MAJEED
Our universe consists of trillions, if not seemingly countless number of galaxies. Many of these galaxies are known as active galaxies or more precisely AGN (active galactic nuclei), because of the emission of high-energy radiations from the center of galaxies due to central supermassive black holes. Different active galaxies burst out jets of radiation and particles forming different shapes depending on the ongoing active events in their center. In this thesis paper, I have discussed the behavior of particles in different geometrical shapes. For the sake of this paper, I have represented three shapes, one is a constant flux tube, the second is diverging environment and the third is an extremely diverging environment (funnel-like structure). The jets emitting from the galactic center are termed as thermal outflows. But these are not the only thing present in outflows structures. Many times, cosmic rays from other galaxies and from void space also interact with thermal outflows and modify its structure and particle dynamics. There are many models to deal with the dynamics of particles, but I have used the hydrodynamic model to deal with these gaseous structures. The solutions are divided into three regions; supersonic region, subsonic region, and unphysical regions. These regions are named on the base of particle speed with respect to sound speed. In unphysical regions, the solution curve shows two speeds simultaneously at one location, which isn’t possible. Here, transonic solutions are interested because a particle following transonic solution can go from subsonic towards supersonic regions or the other way round. In the first chapter, a brief 4 introduction of various concepts is given. In second chapter, Hydrodynamical model (single fluid - thermal outflows) is represented along with numerical solutions. After that in the third chapter, solutions are discussed more qualitatively. At last, hydrodynamic three fluid model is presented and discussed briefly.
Influence of repetition rate on the growth of MgO thin film by pulsed laser deposition technique
(UMT, Lahore, 2022) TAHIR SAJJAD BUTT
The thin films of Magnesium Oxide (MgO) were fabricated onto a substrate of Si (100) by pulsed laser deposition (PLD) of the MgO target with varied repetition rates of 2, 3, 4, and 5 kHz respectively. Nd: YAG laser with a fundamental wavelength of 1064 nm was applied as an energy source with pulse energy of 100 mJ and vacuum as the background environment. The X ray Diffraction (XRD) revealed that the preferred orientation of thin films would be altered from (220) to (311) by increasing thickness. Crystallite sizes were decreased from 65 to 15 nm with an increasing thickness of 307 to 960 nm. It was observed that grain size and film thickness increase with an increase in repetition rate (number of laser shots) while the crystallite size decreases as the repetition rate increases. The surface structure and topology of thin films were analyzed by applying a Scanning Electron Microscope (SEM) which demonstrated that there was no presence of cracks and the film was highly smooth. Such films were suitable as buffer layers for the growing high-quality ferroelectric and superconducting over layers
Laser surface structuring of stainless-steel alloy for biomedical implants application
(UMT, Lahore, 2024) MUHAMMAD SAJAWAL
This work aims to roughen the surface and enlarge the surface area of the sample material, stainless steel alloy 304S, through laser surface structuring (LSS) for biomedical applications. LSS is used to alter the surface of sample material by developing various patterns, textures, and microstructures on the surface. In this study, the surface treatment of stainless steel alloy 304S was performed using 1064nm ND:YAG laser. After LSS, field emission electron microscopy (FESEM) was used to determine the surface morphology. FESEM is an advanced technique employed to obtain the microstructure of the material. The FESEM results showed pits on the stainless steel alloy 304S. Pits greatly increase biomedical implants' surface area, biocompatibility, usefulness, and performance. A wettability test was conducted to check the hydrophilicity or hydrophobicity of the laser-treated sample by using the sessile drop method. Wettability is measured by angle measurement. If the angle is greater than 90 degrees, the surface is hydrophobic, if the angle is less than 90 degrees, the surface is hydrophilic. Wettability determines how well the material will be accepted by the human body. The sample's contact angle was 78 degrees, according to the results. Because the sample's contact angle is below 90 degrees, it is hydrophilic and wettable. Therefore, the treated sample is suitable for bioimplants.
Numerical solution of the Schrodinger equation by feed-forward neural networks
(UMT, Lahore, 2021) SAFOORA ASFA
R ecently, a method has been proposed using Artificial Neural Network (ANN) to solve a boundary value problem, particularly, Schrodinger equation. In order to solve the Schrodinger equation, a trial wave function with many parameters written as a feed forward neural network. A standard back propagation algorithm with momentum term is used to adjust the parameters to find energies and corresponding eigenstates, we studied the infinite square well as an example
Optical properties of Yttrium Oxide thin films prepared by SOL-GEL method
(UMT, Lahore, 2024) YASIR NADEEM
Yttrium oxide (Y2O3) thin films have piqued the interest of researchers in recent years due to their numerous useful uses in optoelectronic and solar devices. Using these thin films for both industrial and scientific uses is standard procedure for researchers. In this study, yttrium oxide thin films are prepared using an application oriented sol-gel approach. The range of molar concentration is 0.1M to 0.6M. Structural and optical properties are acquired using an X-ray diffractometer (XRD) and a Variable Angle Spectroscopic Ellipsometer. At all molar concentrations, XRD analysis verifies the development of pure cubic phases in yttrium oxide thin films. As the molar concentration rises, the crystallinity of thin films increases, which results in an increase in the crystallite size value. Optical analysis confirmed that the prepared samples resulted with wide direct band gap, high refractive index and high transparency in the visible near infrared region. High value of transmission (~ 90%) along with direct band gap (~5.83) is observed for 0.6M molar concetration. The yttrium oxide thin films exhibit a band gap energy ranging from 5.76eV to 5.83eV. Furthermore, as the molar concentration increases, optical-constants, n and k of Y2O3 films tend to rise for all concentrations. Results suggest that this could be advantageous for the material's future application as yttrium oxide thin films proved to be promising candidate for optoelectronic devices. In order to maximize the potential of the approach, this work will stimulate further research on the creation of Y2O3 thin films using the spin coating sol-gel technique.
Polytropic winds
(UMT, Lahore, 2024) SAYOON SARWAR
All stars emit plasma outflows in every stage of their lives. The energy and velocity of these outflows change as a star shifts from accretion phase into a developed main-sequence star. In this thesis we discuss the effect of polytropic index on the energy of the stellar outflows. We first discuss the types of stellar outflows observed,their composition and the means by which they are ejected from the surface of the star. We also discuss the types of models that are used in mapping the outflows of stars in the literature review section. Further, we explain the hydrodyanmical model and present the governing equations for the case of one-fluid model. Lastly, we show results of using the polytropic model on plotting the velocity profile of the stellar wind and show that polytropic index has a great effect on the energy on the wind alongside which we also discuss the applications of this study.
Qualitative and quantitative analysis of Sulphur element in Pakistani rice by calibration free laser induced breakdown spectroscopy (LIBS)
(UMT, Lahore, 2022) ZEESHAN YOUNAS
Laser induced breakdown spectroscopy is being used as rapid, non-destructive in-situ technique equally reliable for compositional analysis for metals and non-metals. In this work a 1064nm Nd:YAG laser was used for the calibration free LIBS. Three samples of the rice were used for the qualitative and quantitative analysis for Sulphur element. Sample-1 was analysed under vacuum and other were determined in the presence of Ar gas filled in the chamber for the confinement of plasma signature. After the identification of Sulphur peaked lines according to NIST (National Institute of Science and Technology) was used for data according to our desired conditions. Plasma properties (Temperature and Density) were calculated and temperature was almost same for all the samples but the density of electrons vary for sample to sample plus for ionized and neutral atoms of Sulphur. Our main concern was to check the permissible value of Sulphur in rice, which then quantified and surprisingly all were above the acceptable value (2ppm) in food. LIBS with a coupled with a suitable medical and agricultural analysing techniques would be more beneficial for the compositional analysis and recommendations in the field of health and agriculture.
Quantum monte Carlo simulation of Schrodinger equation
(UMT, Lahore, 2021) TALHA SAIF
I will discuss the Variational Monte Carlo (VMC) technique which is used to find the energy of the lowest state in quantum mechanical systems. This technique can also be used for many-body systems. In order to understand this, Monte Carlo integration is also discussed here. The Methods of non-uniform random numbers generation are also explored. We studied the Lennard Jones potential by VMC. I have calculated the ground state energy of the harmonic oscillator for a better understanding of this technique.
Simulation of single-particle Schrodinger equation on quantum processor
(UMT, Lahore, 2021) HAFSA ARSHAD
Quantum computing uses superposition and entanglement to perform computation. During this project, we explored the basic quantum circuits, from a single qubit gate to Shor’s factoring algorithm, and implemented them on a quantum processor by using Qiskit. As a main avenue, we studied the Schrodinger equation of a single free particle (V(x) = 0) in one dimension on a quantum processor. In particular, we implemented a 2-qubit quantum simulation algorithm on Qiskit to solve the Schrodinger equation. We showed the time evolution of the state and explained the particle’s position in terms of probabilities for different qubit states.
Solution of KDV and MKDV equation by using (g’/g)- expansion method and space-time fractional methods
(UMT, Lahore, 2023) LAIBA IQBAL
The complex nature of nonlinear evolution equation has always remained a hot debate in the field of plasma physics. Due to its complexity, it is quite challenging to find exact solutions to it using traditional techniques. Therefore, a methodology has been devised which we call  g g '   expansion method. In this investigation we work on space-time KdV, mKdV, KdV-MKdV and space-time fractional ‘KdV-MKdV’ equation. With the help of  g g '  expansion method and extended  g g '   expansion method. Several types of new mathematical exact solutions are obtained, along-with solutions for hyperbolic relations, trigonometric variable functions, and rational expressions. By applying the said technique, we found that these are novel techniques in finding exact mathematical solutions of nonlinear partial differential equations (PDEs) and nonlinear fractional PDEs. Furthermore, graphical representations in the form of two-dimensional and three-dimensional are also presented to highlight the results of our new findings by using MATHEMATICA programming.
Solution of time dependent Schrödinger equation by finite difference method
(UMT, Lahore, 2021) TAYYEBA TAHIRA
We will develop a numerical approach to solve one dimensional time dependent Schrödinger equation. The method is Crank-Nicolson and we will use it to develop a simulation of wave-packet for a free particle to understand its behavior in various scenarios. We will study propagation of wave-packet in free space, tunneling and reflection through potential barrier.
Structural and electrochemical characterization of MoS2/316-L stainless steel electrodes for efficient water splitting
(UMT, Lahore, 2025) MARYAM AHSAN
The thesis investigates the structure-activity relationship between 316L stainless steel and MoS2 thin films developed using chemical vapor deposition in response to the requirement of earth-abundant electrocatalysts to pursue water separation. In order to sulfurize the films, the X rays diffraction characteristic was employed and the films, heated at a temperature ranging between 650 to 750oC were subjected to cyclic voltammetry at the potentials referenced to RHE. The XRD shows traces of MoO3, however, increased temperature gives more clear evidence of MoS2 and a smaller crystal shape. The study shows that the increase in sulfurization temperatures coincide with a better performance of electrodes regarding HER. Improvements are credited to total conversion of phases, and densities of edge sites which are catalytically reachable, and also, better couplings with substrates electronically. Altogether, the findings reveal 750oC sulfurization as the most efficient one in the experimented window, forming 316L stainless steel as low-costs environment to MoS2 electrocatalysts. These results confirm the scalability of MoS2/steel electrodes and the attainability of green-hydrogen systems and encourage subsequent studies of morphology connection-performance relationships, stability, and complete kinetics.
Synthesis and characterization of Cu-MOF
(UMT, Lahore, 2025) TEHREEM FAKHAR
The fast exhaustion of fossil fuels and the growing energy demand in the world has led to the need to come up with efficient, renewable and eco-friendly energy storage systems. The supercapacitors are one of the technologies that have received a lot of attention because of their high power density, high charge discharge rate, and long cycle life. Their performance is however very much dependent on the electrode material employed. Metal-organic frameworks (MOFs) due to their high surface area, tunable pore structure, and high chemical stability have become promising electrode materials of the next-generation supercapacitor. In the study, copper metal-organic framework (Cu-MOF) was effectively prepared by a simple solvothermal synthesis with copper nitrate trihydrate and terephthalic acid in a solution of N,N-dimethylformamide (DMF)-ethanol mixture. It was selected based on the synthesis pathway as it was simple and cost-effective with the capacity to make well-defined crystalline structures. The synthesized Cu-MOF was examined using the X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD analysis verified the crystalline structure of Cu-MOF whose average crystallite size was around 27nm and d-spacing was 0.96nm. The morphology was found to be porous and almost spherical with the help of SEM images. Comprehensively, the research has shown that the easily prepared Cu-MOF is one of the most promising electrode materials in supercapacitors which combine to a great deal in terms of high capacitance, structural stability, and green synthesis, which can be applied in future energy storage systems.
Synthesis and characterization of flexible AL-doped SnO2 based paper electrode for perovskite solar cell application
(UMT, Lahore, 2022) MUHAMMAD USMAN BUTT
Firstly, Perovskite solar cells (PSCs) were disclosed merely in 2012 but their tremendously fast development has reached an efficiency of confirmed 22% presently. PSCs are low-cost and easy to develop than Silicon based solar cells and they can respond to many wavelengths of electromagnetic spectrum which helps them transform more light into electricity. The performance and stability of PSCs are mainly reliant on the Electron transport layer (ETL) material. Lignocellulose (LC) is an abundant, environmentally friendly and a biodegradable fiber. In this research work, LC fiber is used as a substrate instead of glass substrate due to its flexibility and better sustainability. For Electron transport layer materials in PSCs, several semiconductors can be utilized. In this research article, SnO2 is used as an Electron transport layer material because of its low temperature fabrication and wider bandgap. Overall, SnO2 exhibits great optical transparency, chemical stability, conductivity and electron mobility which display its good photovoltaic properties. Aluminium was added into SnO2 as a dopant for the thin film enhancement and for the improved Power conversion efficiency (PCE). Al-doped SnO2 proposes a fine surface coverage of thin films and enhances the conductivity of ETLs which results in the better performance of the PSCs. Different Characterization techniques such as X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Ultraviolet-Visible Spectroscopy (UV-Vis) were used to characterize the synthesized material. The results display that the conductivity of Al-SnO2 increased as the bandgap reduced due to Al-doping and inclusion of LC fiber. Therefore Al-doped SnO2 constituting ETL prepared at low temperature display an enhanced charge transport than that of undoped-SnO2. Hence, Al-doped SnO2 is a favorable contender for ETLs used in PSCs which gives high Power conversion efficiency and stabilization.
Synthesis and characterization of flexible copper doped nickel oxide-based paper electrode for perovskite solar cells applications
(UMT, Lahore, 2022) MUHAMMAD ANAS TOHEED
Perovskite-based solar cells are involved in solar cell production as they enhance power conversion efficiency. The stability and performance of cells are mainly reliant on the materials used as hole transportation materials. One of the vital constituents of the perovskite solar cells is hole transporting layer. The supreme hole transporting material is the one that retains high hole mobility, durable air and mechanical stability and should have energy levels that are a suitable match with the perovskite layer. Lignocellulose (LC) fiber is reflected as a very abundant, eco-friendly, lightweight natural fiber and a biocompatible polymer. In this work Lignocellulose (LC) fiber is used as a substrate. As hole transporting materials (ETM) for perovskite solar cells, many kinds of semiconductor materials can be employed. In this research work, NiO is used as hole transporting material (HTM) due to its superior electrical properties, long-term mechanical and air stability, high hole mobility, and high conductivity. To enhance the properties of NiO thin films and also increase the power conversion efficiency of perovskite solar cells, Cu was added into it as a dopant. Cu-doped NiO (Cu:NiO) has a high conductivity compared to pure NiO. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Ultraviolet-Visible Spectroscopy (UV-Vis), were carried out to characterize the synthesized material. It was indicated that Cu:NiO has better efficiency as a pure NiO when used as hole transporting material (HTM) in the Perovskite solar cells (PSC).

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