United Arab Emirates University
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ENHANCING THE ENERGY EFFICIENCY OF CO2-RICH AMINE SOLUTION REGENERATION THROUGH INNOVATIVE CATALYST AND ADVANCED MEMBRANE MODULE SYSTEM
No full textGlobal warming, which is mostly caused by greenhouse gas emissions, is rapidly becoming a serious issue. Prospective technology for capturing CO2 from point source pollution has recently received a lot of interest. Carbon capture and storage (CCS), particularly through amine-based absorption methods, is one of the most developed industrial processes for capturing anthropogenic and natural CO2. Although amine-based absorption remains the most mature technology for industrial CO2 capture, yet its largescale deployment is hindered by the high energy requirement of solvent regeneration. To address this challenge, we explored both catalytic and membrane-assisted approaches to improve the efficiency of CO2 desorption from rich amine solutions. Catalytic strategies employing nanocomposites such as MoO3/ZIF-67 modified with phosphotungstic acid (HPW) and MXene@MOF hybrids introduced abundant Lewis and Brønsted acid sites, significantly accelerating carbamate breakdown and proton transfer for promoting regeneration. These catalysts enhanced CO2 desorption rates significantly and increased CO2 release while reducing regeneration energy consumption by up to one-third compared with conventional methods. In parallel, membrane-based techniques were advanced through the design of hollow fiber membrane contactors (HFMCs). Commercially available PTFE and self-fabricated PES-based hollow fiber membranes module (HFMM) were developed, with PES membranes further modified using LiCl and TiO2 to optimize pore structure, mechanical stability, and surface chemistry. These modifications improved mass transfer and facilitated solvent regeneration, improving stripping efficiency under favorable operating conditions. Integration of catalytic materials within membrane modules further boosted desorption, demonstrating the synergistic potential of catalystmembrane hybrid systems. Collectively, these studies highlight that advanced catalysts and hollow fiber membranes module system can substantially reduce the energy penalty associated with amine regeneration. The integrated approach provides a promising pathway for developing energy-efficient, scalable CO2 capture technologies to mitigate industrial greenhouse gas emissions
DEVELOPMENT OF COMPOSITE MEMBRANES AND NANOFLUID ABSORBENTS INCORPORATING SURFACE-FUNCTIONALIZED NANOPARTICLES FOR ENHANCED CO₂ ABSORPTION IN GAS–LIQUID MEMBRANE CONTACTORS
No full textNatural gas sweetening demands the efficient removal of CO₂ to enhance heating value and prevent equipment corrosion. Gas–liquid membrane contactors (GLMCs) have garnered attention as promising solutions to traditional separation methods due to their modularity, high interfacial area, and energy efficiency. Nonetheless, they suffer from some serious challenges such as membrane wetting, while absorbents either exhibit low absorption capacity or high energy demands and corrosion. This work addresses these limitations through two complementary strategies. In the first, ZnO nanoparticles were hydrophobically functionalised and incorporated into polymer matrices to fabricate composite membranes with superior hydrophobicity and reduced pore wetting. In the second, suitably surface-modified ZnO nanoparticles were dispersed in absorption solvents as nanofluids to intensify gas–liquid mass transfer. The nanofluids were tested in hollow fiber membrane contactors to investigate the solvent-side enhancement. Material characterization confirmed successful modification and stable dispersions. Experimental studies demonstrated that the modified membranes effectively suppressed wetting and achieved higher CO₂ flux, and the nanofluids boosted absorption performance while enabling operation with lower amine concentration. Performance evaluations were carried out to examine the influence of key operating parameters on CO2 absorption performance in both membrane- and solvent-based systems. Together, the dual approach of membrane modification and solvent intensification offers a practical route toward high performance, energy-efficient GLMC systems for CO2 removal from natural gas
DEVELOPMENT AND EXPERIMENTAL VALIDATION OF A BIO-BASED CO2 PURIFICATION MEDIUM DERIVED FROM PUFFED RICE WASTE FOR INDOOR AIR QUALITY IMPROVEMENT
No full textIndoor environments are crucial for human activity, as people spend over 90% of their time indoors. This extensive indoor presence makes these spaces crucial for overall well-being. The growing awareness of Indoor Air Quality\u27s (IAQ) impact on health, productivity, and wellness contrasts with buildings\u27 contributions to greenhouse gas emissions, particularly through construction materials such as exterior walls, upper floors, and interior finishes. Classrooms are especially concerning because they house many students who are exposed to indoor air pollutants for extended periods. Given the significance of IAQ in educational settings, there is an urgent need for effective solutions to improve air quality. Additionally, the United Arab Emirates (UAE) faces a significant environmental challenge, as nearly 40% of imported rice is wasted each year. However, this waste also presents an overlooked opportunity for sustainable resource development.This research aims to develop and optimize a purification medium made from waste rice, with a focus on reducing carbon dioxide (CO₂) levels in classrooms. Lowering CO₂ is essential for enhancing student well-being, learning quality, and cognitive performance. The material’s effectiveness was systematically evaluated through a comprehensive assessment, including structural analysis, detailed examination of its morphological properties, and testing of its CO₂ reduction efficiency. This study is grounded in a comprehensive and systematic research framework aimed at evaluating and optimizing the performance of a novel bio-based purification material. The material, developed from treated puffed rice media, is designed to enhance indoor air quality (IAQ) through the passive reduction of CO₂.. The methodology combines experimental approaches, chemical functionalization, and optimization techniques, followed by simulation modeling, to ensure both effectiveness and applicability in a real-world indoor environment. This study demonstrates the practicality of integrating waste byproducts into sustainable technologies, showcasing potential future applications in various indoor environments. The experimental findings revealed that optimizing the puffing conditions of rice, specifically at 18% moisture content and 260 °C, yielded the greatest expansion, producing a thickness of approximately 1.2 cm with enhanced porosity suitable for gas adsorption. To further improve performance, the material was chemically functionalized using sodium hydroxide (NaOH). FTIR, TGA, and XRD analyses confirmed that NaOH treatment significantly enhanced the surface chemistry, thermal stability, and crystalline structure of the puffed rice media, thereby improving its suitability for CO₂ capture at typical indoor operational temperatures. SEM imaging supported these results by revealing improved pore structure and connectivity in treated samples. Performance testing demonstrated that puffed rice media treated with 2.0 M NaOH achieved the highest adsorption capacity, removing approximately 0.37 mol of CO₂ (38%) under laboratory-scale testing. Geometric optimization showed that circular purification discs provided superior uniformity, stability, and ease of integration compared to square or cuboid forms, making them practical for wall- or ceiling-mounted systems. These discs can be produced in several dimensions and colors, allowing architectural adaptability and seamless integration into indoor spaces. Controlled chamber experiments applying the real indoor environment confirmed that CO₂ reduction efficiency was strongly influenced by temperature, relative humidity, and material coverage, with the optimal condition (25 °C, 55% RH, 45% coverage) reducing CO₂ concentration from 1001 ppm to 684 ppm within the tested period, with an average reduction rate of 79.25 ppm/hr. Statistical modeling using Response Surface Methodology (RSM) and ANOVA demonstrated strong predictive capability (R² = 97.38%, adj. R² = 94.42%) and identified material coverage as the most significant factor. The model predicted a maximum uptake of 312.1 ppm under optimal conditions with high desirability (0.9766). Long-term extrapolation using kinetic modeling further indicated sustained adsorption capacity, with saturation projected after approximately 2.1 years of continuous daily operation. Additionally, the material’s versatility in shape and color allows for various design applications, making it suitable for different architectural and decorative purposes. It is easy to implement while remaining sustainable and eco-friendly. Compared to conventional materials such as coconut-shell activated carbon or bamboo-based carbon, which require high-temperature activation (\u3e800 °C) and exist mainly in granular or powdered forms, the puffed rice media demonstrates equivalent adsorption potential through a low-temperature process and easily deployable disc-shaped geometry. This highlights its competitive advantage for passive, surface-based purification systems in indoor environments. This study demonstrates that chemically modified puffed rice media represents a practical, sustainable, and scalable solution for reducing CO₂ in classrooms and similar indoor spaces. It combines effective adsorption performance with low energy requirements, aesthetic adaptability, and long operational life, making it a promising innovation for both indoor air quality improvement and sustainable waste utilization in the built environment. The findings present a distinctive strategy for reducing indoor CO₂ levels, aligning with global efforts to foster sustainability and resource efficiency in construction practices
ENHANCEMENT OF AERATION AND ACTIVATED SLUDGE PROCESSES USING MICRONANOBUBBLES FOR EFFICIENT WASTEWATER TREATMENT
No full textAeration is considered one of the most reliable and efficient processes in wastewater treatment. However, conventional aeration systems show low performance with respect to the gas transfer during the treatment process. This poses a challenge in maintaining sufficient dissolved oxygen (DO) concentrations essential for the treatment. The use of micronanobubbles (MNBs) in the aeration process has been proposed as effective tool in water and wastewater treatment owing to their stability and longevity. MNBs’ stability is a distinctive property resulting from several mechanisms, including the repulsion force due to charged surfaces that helps bubbles to resist coalescence/bursting. MNBs’ longevity is represented by their lifespan in water before disappearing. This study focused on the potential use of MNBs in the aeration system of the activated sludge process during wastewater treatment. First, the fundamental properties of the underexplored submicrobubbles (SMBs), as a subset of MNBs, are identified. Then, the effects of SMBs generation conditions such as temperature, aeration time, and water volume on their properties are recognized. After that, this study examined the impact of different generation methods and conditions on oxygen transfer dynamics and the formation of bubbles in both clean water and activated sludge system. After that, the employment of intermittent aeration using different-sized MNBs in an activated sludge system was studied and compared to the use of continuous conventional aeration system under different experimental conditions. Results indicated that (1) submicrobubbles (SMBs), with a median diameter of 2 μm, showed high longevity and stability in water. (2) MNBs with sizes ranging between 100 nm and 2 μm exhibited a higher efficiency in oxygen transfer rates up to two-fold compared to bubbles with sizes bigger than 10 μm. Applying a low air flow rate using MNB generator provided sufficiently small-sized bubbles and higher DO concentration compared to larger bubbles obtained at a higher flow rate using ultrafine diffuser systems. (3) Using intermittent hybrid aeration system, of different-sized MNBs, in activated sludge systems showed better wastewater treatment efficiency compared to continuous aeration used in conventional systems. More specifically, higher removal of COD and TKN from real wastewater was observed under different MLSS values. (4) The removal kinetics of COD and TKN were examined in a batch activated sludge system using zero, first, second, and Grau-second order kinetics. COD removal for both systems, under all examined MLSS values, was best described by Grau-second order kinetics. On the other hand, TKN removal did not follow a specific kinetic model
إعادة توطين اللاجئين في ضوء أحكام القانون الدولي
No full textAnalytical Study of the Principles of Non-Refoulement and Resettlement of Refugees in Light of the Provisions of International Law
The refugee crisis is one of the most significant challenges facing the modern international community. A report from the United Nations High Commissioner for Refugees (UNHCR) has shown that the number of refugees worldwide has risen to approximately 110 million. This means that a large number of individuals are living outside their home countries, residing in host nations as refugees. While hosting refugees is an international obligation that host countries must adhere to, in some cases, the increasing number of refugees places an additional burden on these nations, which they may be unwilling to bear.
This study will focus on the fundamental principle underlying the Refugee Convention: the principle of non-refoulement. This principle prohibits states from returning refugees to places where their lives may be at risk or where they may face persecution. Accordingly, the study will begin by defining humanitarian refugees and the legal framework governing host countries. Then, it will discuss the principle of non-refoulement, along with its exceptions. Following that, it will examine the principle of refugee resettlement, which involves relocating refugees to a third country, whether voluntarily or forcibly. After that, the study will delve into forced resettlement as a measure that some states resort to in order to evade hosting refugees for various reasons
CHINESE TEACHERS’ ATTITUDE, EFFICAY, AND PRACTICE OF INCLUSIVE EDUCATION IN THE UAE PUBLIC SCHOOLS: AN EXPLANATORY STUDY
No full textChinese language teachers in UAE public schools represent a key demographic in achieving the nation’s vision for educational inclusion. This dissertation examines how these teachers’ attitude and self-efficacy influence their inclusive education practice. The main objective is to model and explain the relationship between these three constructs within the UAE setting. The study employs an explanatory sequential mixed-methods design, utilizing a quantitative survey for model testing followed by in-depth qualitative interviews for deep-seated explanations. The quantitative analysis establishes a significant structural relationship, notably demonstrating a full mediation of teacher self-efficacy between their attitude and inclusive practice. A Structural Equation Model is developed in this dissertation, which also integrates the role of professional awareness in this process. By combining integrated data, the research not only identifies what the nexus of attitude, efficacy, and practice is and how they interact, but also explores the why behind these findings, offering actionable recommendations for the professional development and future implementation of inclusive education among international Chinese language teachers
ENHANCING CONSTRUCTION PROJECT SUCCESS IN UAE THROUGH AGILE PROJECT MANAGEMENT
No full textThis research examines the development of project management practices in the United Arab Emirates, as the country is known for its large-scale strategic development projects. The increasing complexity of these projects renders traditional project management approaches insufficient for addressing their dynamic challenges. The main purpose of this dissertation is to examine how Agile Project Management (AGPM ) enhances construction project success in the UAE by improving time and cost performance. The research examines the role of AGPM as a mediator that connects fundamental project success factors to overall project success. The research employed quantitative methods to analyze survey data and project information, enabling the assessment of key variables, including top management support, effective team communication, health and safety regulations, and project complexity, in relation to project success. Project success, in terms of both time and cost, showed positive relationships with top management support, effective communication, adherence to health and safety regulations, and Agile Project Management (p \u3c 0.05). Project complexity scale failed to produce a statistically significant negative effect on project success (p \u3e 0.05). The research confirmed that Agile Project Management functions as a mediator between top management support and effective communication, Health and safety regulations and project success, but it does not affect project complexity. The study adds value to both theoretical and practical aspects by demonstrating the importance of flexible leadership approaches in project management. The research provides actionable recommendations for UAE project planners to integrate Agile principles into their planning processes which will improve project results and enhance their ability to handle uncertainty. This research fills a literature gap through UAE-based empirical evidence which demonstrates how Agile practices boost project success in fast-changing and complex development projects
التَّسوية الجزائيَّة في قانون الإجراءات الجزائيَّة الإماراتي
No full textPenal Settlement in the UAE Criminal Procedure Law In pursuit of enhancing justice and improving the efficiency of the criminal justice system, modern legislations have witnessed significant developments in the mechanisms through which the state exercises its right to impose sanctions. This has been achieved through the adoption of innovative approaches in criminal policy. Several legal systems have embraced alternative mechanisms to resolve criminal disputes outside the framework of traditional criminal proceedings, whether in cases of violations (infractions), misdemeanors, or even certain felonies. In line with this approach, the UAE legislator introduced the Criminal Settlement System in the latest amendment to the Federal Criminal Procedure Law as an alternative to traditional criminal proceedings. The objective is to alleviate the burden on courts and reduce the number of cases brought before them, thereby enhancing the speed and efficiency of adjudicating high-priority cases. The Criminal Settlement System is defined as a procedure initiated by the Public Prosecution before instituting criminal proceedings, wherein the prosecution offers the accused the possibility of accepting certain measures or specific penalties for legally designated crimes in exchange for a full confession of guilt. This agreement is subject to approval by the competent judge, and upon ratification, the criminal case is dismissed without resorting to conventional trial proceedings. This mechanism facilitates a consensual resolution of criminal disputes between the parties involved. This study aims to conduct a comparative analytical examination of the Criminal Settlement System in UAE legislation, while also reviewing similar legislative experiences in other jurisdictions. The objective is to identify points of convergence and divergence between the UAE\u27s model and other legal systems that have adopted the Criminal Settlement System as an alternative to traditional criminal proceedings.
Additionally, the study explores the legal nature of the Criminal Settlement System, the conditions and procedures governing its application, as well as the types of offenses eligible for this mechanism. It further examines the legal implications of a successful or failed Criminal Settlement System agreement. The study concludes that the Criminal Settlement System plays a pivotal role in criminal procedures, requiring enhanced awareness and understanding among legal professionals and relevant stakeholders. Given that the UAE has adopted this system based on the French model, further research and practical evaluations are necessary to assess its effectiveness and applicability, especially in light of the absence of its implementation in the national procedural legislation
ADVANCING SECURITY SAFEGUARDS IN LARGE LANGUAGE MODELS THROUGH MULTI-AGENT SYSTEMS
No full textThis thesis focused on enhancing the safe use of Large Language Model (LLM) through the innovative use of a Multi-Agent System (MAS). As LLMs like ChatGPT became essential to our everyday interactions, the need to maintain the safe use of these systems increased. This research thoroughly assessed the current security measures in place for LLM, pointed out their limitations and developed new and more effective security strategies. The core of the proposed solution was a MAS designed to ensure that all data processed by LLM met guidelines including Privacy, Confidentiality, and Ethical standards before reaching the user. The system involved multiple agents working together: A Coordinator that handled user queries and an Audit Agent that checked the LLM Agent’s outputs against guidelines. This setup aimed to prevent any misuse of the technology.
In our evaluation, the proposed MAS achieved high accuracy in classifying model outputs as safe or blocked. This demonstrated that an Audit Agent supervising an LLM Agent could effectively reduce unsafe or non-compliant responses. Overall, the system consistently enforced these standards without significantly affecting regular interactions. By using new techniques and adding them to the MAS, this study improved LLM usage beyond previous levels. This approach proved essential as LLM became more widespread. Through this thesis, I proposed a safer digital environment for users of LLM, preventing potential abuse of such systems
COBALT LAYERED DOUBLE HYDROXIDE AS ADVANCED ELECTRODE MATERIALS FOR SUPERCAPACITORS AND ELECTROCATALYSIS
No full textDue to the high demand for sustainable energy storage options and efficient energy conversion devices, extensive research has been conducted on various electrode materials. This thesis is concerned with the fabrication of electrode material mainly using cobalt-based material, particularly cobalt layered double hydroxides (Co-LDH) with the combination of nitrogen-doped carbon nanotubes (N-CNTs) to be used in supercapacitors and oxygen evolution reactions (OERs) applications. The main objective is to enhance the electrochemical performance of supercapacitors and to develop a novel electrode material for a more stable and efficient OER in alkaline medium.
The methodology involved a one-step hydrothermal procedure to synthesize the two-dimensional ultrathin Co-LDH nanosheets, which also included the in-situ integration of N-CNT to form Co-LDH/N-CNT composites. Moreover, the electrodes were prepared by coating the material on conductive Ni foam substrates and then immersing them in an alkaline 2 M KOH (supercapacitor) and 1 M KOH (OER) electrolyte for characterization and electrochemical testing. Different characterization techniques such as XRD, FT-IR, SEM, and TEM were used to study surface morphology and the structure of the material. Their electrochemical performance was investigated using cyclic voltammetry (CV), galvanostatic charge–discharge tests (GCD), electrochemical impedance spectroscopy EIS), and cyclic stability tests The OER testing was conducted in 1 M KOH electrolyte using the same 3-electrode system set up for cyclic voltammetry (CV), linear sweep voltammetry (LSV), and Chronopotentiometry (CP).
The results of the experiment showed that the performance of the electrode has significantly improved in terms of specific capacitance after the integration of carbon nanotubes compared to pristine Co-LDH. This is mainly because the incorporation of nitrogen-doped carbon nanotubes plays a vital role in enhancing the conductivity and mechanical stability of Co-LDH.
Although the theoretical capacitance of Co-LDH is considered high, the material has consistently suffered from low electrical conductivity and structural stability, which limit its performance. Thus, this research fills this gap by developing a strategy that helps overcome the restrictions and limitations of conventional Co-LDH by combining it with N-CNTs, thereby extending the material\u27s application to water splitting. This also demonstrates the role of hybridization in producing a high-performing energy technology.
This thesis contributes to the field of energy storage and energy conversion by filling the void between the development of supercapacitor electrode materials and water splitting catalysts by designing a single material for both applications, which is more practical and cost-efficient