Fundamental Studies of Positron Scattering from Atoms and Molecules

This thesis presents measurements of low-energy positron scattering from Argon and C60. Absolute elastic differential cross sections are presented for positron scattering from Argon in the energy range 2 to 50 eV, as well as absolute total elastic and inelastic cross sections up to 20 eV. These results are compared with theoretical calculations using the convergent close-coupling (CCC) and relativistic optical potential (ROP) methods and it was found that generally the measurements were in closer agreement with the CCC method than the ROP method across the energy range, although the ROP method was an excellent description of the total inelastic cross section in this energy range. Argon was also the focus of the first results from the newly developed positron reaction microscope. Experimental techniques were developed to produce measurements of the kinematics of positron-induced single ionisation of Argon. Single ionisation events were detected in coincidence and their momenta reconstructed using data analysis methods detailed in this thesis. Although further work is required to provide total differential cross sections, the initial data presented in this thesis is in alignment with expectations based upon available theory and experiment and provides a promising starting point for future studies using the positron reaction microscope. Finally, a search was conducted for resonant features in the total scattering and Positronium formation cross sections of C60. Motivated by the predictions of Gianturco and Lucchese (1999), which indicated experimentally-accessible resonances, the present data does not show any features. However, the current results in this thesis represent the first preliminary measurements of the total scattering and Positronium formation cross sections for C60 and follow the expected trend for positron-molecule scattering. Additional data to be collected in the future, would allow for confirmation of the presence, or lack thereof, of resonant features with a higher statistical confidence

Towards a circular economy: fabrication and characterization of biodegradable plates from sugarcane waste

Bagasse pulp is a promising material to produce biodegradable plates. Bagasse is the fibrous residue that remains after sugarcane stalks are crushed to extract their juice. It is a renewable resource and is widely available in many countries, making it an attractive alternative to traditional plastic plates. Recent research has shown that biodegradable plates made from Bagasse pulp have several advantages over traditional plastic plates. For example, they are more environmentally friendly because they are made from renewable resources and can be composted after use. Additionally, they are safer for human health because they do not contain harmful chemicals that can leach into food. The production process for Bagasse pulp plates is also relatively simple and cost-effective. Bagasse is first collected and then processed to remove impurities and extract the pulp. The pulp is then molded into the desired shape and dried to form a sturdy plate. Overall, biodegradable plates made from Bagasse pulp are a promising alternative to traditional plastic plates. They are environmentally friendly, safe for human health, and cost-effective to produce. As such, they have the potential to play an important role in reducing plastic waste and promoting sustainable practices. Over the years, the world was not paying strict attention to the impact of rapid growth in plastic use. As a result, uncontrollable volumes of plastic garbage have been released into the environment. Half of all plastic garbage generated worldwide is made up of packaging materials. The purpose of this article is to offer an alternative by creating bioplastic goods that can be produced in various shapes and sizes across various sectors, including food packaging, single-use tableware, and crafts. Products made from bagasse help address the issue of plastic pollution. To find the optimum option for creating bagasse-based biodegradable dinnerware in Egypt and throughout the world, researchers tested various scenarios. The findings show that bagasse pulp may replace plastics in biodegradable packaging. As a result of this value-added utilization of natural fibers, less waste and less of it ends up in landfills. The practical significance of this study is to help advance low-carbon economic solutions and to produce secure bioplastic materials that can replace Styrofoam in tableware and food packaging production