Theses (Faculty of Science and Technology)
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A DE Természettudományi és Technológiai Kar Tanácsának 2009. november 25.-i határozata alapján a jövőben elektronikus formában is elhelyezésre kerülnek a szakdolgozatok a Debreceni Egyetem Egyetemi és Nemzeti Könyvtár által működtetett egyetemi archívumban, a DEAba. A szakdolgozatok az archívumból kizárólag a Debreceni Egyetem IP-címeiről hozzáférhetőek, azokat nem lehet kinyomtatni, és azokból szövegrészeket nem lehet kiemelni.
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Tétel Korlátozottan hozzáférhető Dissipation in Lagrangian FormalismThelge, Yoon Ayanajee Peiris; Nagy, Sándor; DE--Természettudományi és Technológiai Kar--Fizikai IntézetThis thesis examines dissipative forces in physical systems in both microscopic and quantum level. The system-environment interaction is modeled by assuming that the environment is composed of simple harmonic oscillators and that there is a linear interaction between these oscillators and the system. The classical case is solved by determining the retarded Green’s function, which yields the equation of motion of the system. For quantum dissipation, the Lindblad master equation is used to describe the time evolution of the reduced density matrix of the system, and the propagator is investigated to identify important parameters, including the term of Newton's friction force.Tétel Korlátozottan hozzáférhető Land cover classification using machine learning algorithms on GEE, and its relationship with gaseous air pollutants based on remote sensing dataGuaman Pintado, Pamela Maricela; Szabó, Szilárd; DE--Természettudományi és Technológiai Kar--Földtudományi IntézetThis study explores the application of machine learning algorithms on Google Earth Engine (GEE) for land cover classification and examines the relationship between different land cover types and gaseous air pollutants (O3, NO2, SO2) using remote sensing data. The research focuses on evaluating the performance of various machine learning techniques, such as Random Forest, Support Vector Machines, and CART, in classifying land cover types.Tétel Korlátozottan hozzáférhető Preparation of Pyridine-contained Macrocycle Ligand with Hydroxamates SidearmsKongphaly, Douangdara; Csupász, Tibor; Gyula, Tircsó; DE--Természettudományi és Technológiai Kar--Kémiai IntézetThis thesis focuses on the synthesis of hydroxamate derivatives in the preparation of pyridine-containing macrocycle ligands. These ligands have potential applications as MRI contrast agents. The synthesis of the ligand involves several steps, including the synthesis of a hydroxamate derivative and the purification of the final product. These steps require careful optimization of reaction conditions and reagents to achieve high yields and purity. This research is expected to lead to the development of a new pyridine-containing macrocycle ligand that has potential applications as an MRI contrast agent.Tétel Korlátozottan hozzáférhető Examination of the Influence of the Additives of Plastic on the Mechanical ProperitiesKhalid Mutlaq, Hajer; Czifrak, Katalin; DE--Természettudományi és Technológiai Kar--Biotechnológiai IntézetIn this research, Polycaprolactone was the polymer of interest. Five experiments were performed and they all started with PCL as the base polymer and experienced changes in mechanical properties after composting, the specific compositions and conditions of each experiment, including the addition of monoglyceride sunflower oil, difference in PCL molecular weights, incorporatio of Hexamethylene diisocyanate, a catalyst (Sn(Oct)2), and Polyethylene glycol to varying extents led to unique outcomes, which resulted in variations in stiffness, ductility, and tensile strength for each polymer.Tétel Korlátozottan hozzáférhető design and development of a controller for controlling touchscreens for the purpose of information boardTran, Tien Thanh; Csarnovics, Istvan; DE--Természettudományi és Technológiai Kar--Fizikai IntézetCreation of a bulletin board using Touchscreen as a display and controlled by a microcontroller. Bulletin will show the important about the Insitute like Map of the insitute and the detail of professors who work in the institute. Controlled my a microcontroller- Raspberry Pi, connect with a joystick to act like a mouse to control the screen.Tétel Korlátozottan hozzáférhető Analysis of Honey Samples by 2D NMR ExperimentsPellegrini Silva, Raul; Timári, István; DE--Természettudományi és Technológiai Kar--Kémiai IntézetNMR Analysis of dew and acacia honey by 1 and 2D HSQC, TOCSY, and HSQC-TOCSY techniques were used to evaluate COLMARm automatic metabolomic detection, the main fractions of honey, and for a view of the usage of NMR for fingerprint detection.Tétel Korlátozottan hozzáférhető Glucose Cross-linked Biocompatible PolyurethaneBaleid, Alawi; Sándor, Kéki; DE--Természettudományi és Technológiai Kar--Kémiai IntézetVarious polyurethane samples were manufactured in this research utilizing biodegradable and biocompatible raw materials such as poly(ε-caprolactone)-diol, 1,6-Hexamethylene diisocyanate, and glucose. The amounts of diol and diisocyanate were held constant while the amount of glucose was varied to investigate the effect of glucose on crosslinking and the mechanical properties of the sample. Using a swelling test, the crosslink density was assessed. In addition, a tensile mechanical test was conducted to assess the materials' mechanical properties.Tétel Korlátozottan hozzáférhető Duckweeds, general characteristics and applicability in practiceMuli, Grace Ndanu; Mészáros, Ilona; DE--Természettudományi és Technológiai Kar--Biológiai és Ökológiai IntézetThis work aimed to reveal what characteristics duckweeds have and how they have become one of the important plant group potentially used for phytoremediation against toxicity in wastewaters. Application of duckweeds can be obtained from its biomass for animal feeding or for production of biofuel amongst other advantages.Tétel Korlátozottan hozzáférhető gene expression under low humidity conditions in woodliceAtassi, Nour; Nagy, Nikoletta; DE--Természettudományi és Technológiai Kar--Biológiai és Ökológiai Intézetthe genetic regulation of low humidity response in woodlice is a topic of great interest that should be investigated, therefore we aimed at analyzing gene expression patterns in common rough woodlice. Our results summarized that we could not find any relationship between the tested gene HSP 40 and the desiccation tolerance. The results encourages us to further investigate more genes that could be regulating the low humidity stress response in woodlice.Tétel Korlátozottan hozzáférhető Application of Microgrids in Renewable Energy SystemGu, Dengxu; Trencsényi, Réka Eszter; DE--Természettudományi és Technológiai Kar--Fizikai IntézetThis thesis first expounds the concept of microgrid, introduced the main components of microgrid. The maximum power point tracking method for photovoltaic cells is studied. Analyzes the microgrid energy storage system and how to control, inverter grid-connected control. The simulation platform of microgrid system is built. Finally, the future of microgrid is prospected.Tétel Korlátozottan hozzáférhető Hydration mechanism of Polyamide and Polyimide AerogelsTran, Hoang Thanh Truc; Forgács, Attila; DE--Természettudományi és Technológiai Kar--Kémiai IntézetA detailed inspection of the microstructure of polyamide and polyimide aerogels related to applications in humid environment was carried out and centered on their hydration mechanism. The structures of these porous materials remain intact under hydrated conditions. The two synthetic aerogels were characterized in the dry state by IR spectroscopy, Nitrogen adsorption-desorption porosimetry and scanning electron microscopy (SEM). As an indirect approach to study the hydration induced structural changes, the aerogels were hydrated stepwise, and investigated by liquid-state nuclear magnetic resonance (NMR) relaxometry. From the relaxometry measurements, we can get information on the different structural regions in association with bound water, and therefore, on the hydration mechanism of the aerogels.Tétel Korlátozottan hozzáférhető Co-crystals of Furosemide with Theobromine/TheophyllineTran Dang , Khoa; Bényei, Attila; DE--Természettudományi és Technológiai Kar--Kémiai IntézetFurosemide is an essential pharmaceutical compound. Preparation of stable co-crystal, using furosemide as an API and human-friendly compound: theobromine and theophylline as co-formers. Ethanol is used in this study because of its low evaporation point and acceptable solubility with both API and co-formers. In this study, we have successfully synthesized the co-crystal of Furosemide and Theobromine, which is proven by PXRD pattern of FUR:TB = 1:1 and 1:2 sample. This is a promising result because these co-formers are biologically consumable compounds.Tétel Korlátozottan hozzáférhető Investigation of the degradation of different polycaprolactones and polyurethaneKaga, Deborah; Czifrák, Katalin; DE--Természettudományi és Technológiai Kar--Biotechnológiai IntézetThis thesis investigates the biodegradation of different polycaprolactones and polyurethane. The biodegradation of these polymers was monitored through the production of CO2. In this article, we look at the factors that affect the biodegradation of polymers. We also look at the roles these polymers play in curbing plastic waste. This also highlights the importance of biodegradable polymers in different industries such as the medical industry, packaging, etc.Tétel Korlátozottan hozzáférhető Metal Complexes of Histidine Containing PeptidesShafiyev, Zamin; Varnagy, Katalin; DE--Természettudományi és Technológiai Kar--Kémiai IntézetThe aim of my studies was to determine the exact coordination modes of copper(II) complexes of ProHisLeu tripeptide and investigate the electrochemical characteristics of those complexes. In this work, the combined application of potentiometric, spectroscopic, and electrochemical measurements on the Cu(II) complexes of ProHisLeu was studied, in samples containing metal ions and ligand in 1:1 and 1:5 ratios. The ligand deprotonation constants were calculated using SUPERQUAD software. The exact coordination modes and electrochemical characteristics of copper(II) complexes of ProHisLeu tripeptide were determined.Tétel Korlátozottan hozzáférhető SOD activity and phosphorylation of histone H2AX as responses to oxidative stress caused by alterations of PP2A functioning in ArabidopsisAdedokun, Oluwatosin Peace; Máthé, Csaba; DE--Természettudományi és Technológiai Kar--Biológiai és Ökológiai IntézetFrom the SOD activity it is seen that the Fe-SOD activity showed the most sensitivity to induced oxidative stress denoting higher ROS. This emphasizes the phototoxic effects of ROS. The increased sensitivity in the fass-5 B regulatory subunit mutant shows that the regulation of PP2A plays a role in the mediation of SOD activity in response to oxidative stress. The DNA damage as a result of oxidative stress is higher in the homozygous recessive fass-5 mutant but for the heterozygous fass-5 genotype we did not detect marked changes in histone H2A phosphorylation . There seems to be a little positive effect.Tétel Korlátozottan hozzáférhető The effects of novel SGLT2 inhibitors on intestinal smooth muscle activityAbilkassym, Dauren; Uray, Karen; DE--Természettudományi és Technológiai Kar--Biotechnológiai IntézetDue to their unique mechanism of action, inhibitors of the sodium-glucose cotransporter type 2, in addition to glycemic and metabolic effects, have the ability to exert an inhibitory effect on various aspects of the pathogenesis of micro- and macrovascular complications of diabetes mellitus. Further large-scale clinical trials should provide information on which groups of patients with type 2 diabetes mellitus can benefit most from the administration of glyflozins while minimizing the risk of adverse events. Drugs such as BEVA22-2, SzK154 and SzK153 represented their mechanism and sidechains. Which lowers gastrointestinal side effects and improve patient adherence to drug regimens. In type 2 diabetic mice, dapagliflozin therapy reduces arterial stiffness, endothelial dysfunction, and vascular smooth muscle dysfunction, as well as changing the microbiota composition gradually. Collectively, the improvements in generalized vascular function may represent an important mechanism underlying the smooth muscle activity benefits of SGLT2 treatment.Tétel Korlátozottan hozzáférhető Applications of Superconductors in MRI ScannerNawaz, Muhammad Hassan Nawaz; Kósa, János Árpád; DE--Természettudományi és Technológiai Kar--Fizikai IntézetIn this thesis, main focus was to design a novel superconducting magnet for medical MRI applications. Traditionally, Magnet section is the main component of MRI systems which consists of conventional permanent magnetic coils. However, in this project, I replaced the conventional permanent magnet with superconducting magnet which consists of YBCO superconducting tape and coils.Tétel Korlátozottan hozzáférhető Understanding Significance of Cladocera biodiversity potential of Upper Tisza regionWamalwa, Henry; Gyulai, István; DE--Természettudományi és Technológiai Kar--Biológiai és Ökológiai IntézetAnalysis of the cladocera diversity in oxbow lakes. Cladocera are known to be sensitive organism to slight environmental changes. Additionally, they occupy the middle of the trophic level structure hence they can be used to determine abundance or lack of it in an ecosystem. We can also know previous and current condition of water bodies in terms of physical, chemical and ecological aspect by finding out which species of Cladocera are in open water and those decaying in the sediment. This information can be used in making conservation decisions of aquatic ecosystems.Tétel Korlátozottan hozzáférhető Examination of The Short Circuit Current in Power System Using Matlab ProgramYu, Yue Yue Jr; Kósa, János Árpád; DE--Természettudományi és Technológiai Kar--Fizikai IntézetIn this thesis, I have worked on theoretical calculation for short circuit current and used Matlab program to examine the short circuit to ensure the right parameters that I chose as well. There is a given grid, I calculated the parameters for switch gears. Later the grid will develop. For this reason, I calculated the maximum opportunity of development of the grid without changing of air coils and examined more possibilities by using Matlab program.Tétel Korlátozottan hozzáférhető Analysis of stout beers using HPLC-MSErdenebayar, Dulguun; Róth, Gergő; DE--Természettudományi és Technológiai Kar--Kémiai IntézetThe goal of my thesis was searching chemical components in industrial, craft, and home brewed stouts using HPLC-MS analytical technique and differentiate what is in the home brewed, what is not in craft/ industrial beer. We have used seven different stout beers in the experiment home-brewed, craft beer and big industrial beer. For the analytical instrument we have used microTOF Bruker Daltonics instrument.