580 Works

Predicting Crop Yield Using Crop Models and High-Resolution Remote Sensing Technologies

Matteo Giuseppe Ziliani
By 2050, food consumption and agricultural water use will increase as a result of a global population that is projected to reach 9 billion people. To address this food and water security challenge, there has been increased attention towards the concept of sustainable agriculture, which has a broad aim of securing food and water resources while preserving the environment for future generations. An element of this is the use of precision agriculture, which is designed...

Unactivated Alkyl Chloride Reactivity in Excited-State Palladium Catalysis

Aidana Gimnkhan
In the last centuries, transition metal chemistry beсome one оf the mоst іmportant tооls for synthesis of valuable organic compounds and different chemical transformations. In particular, transition metal catalysis are capable of forming novel cross coupling bonds. In this background, photocatalysis was developed later to create new chemical transformations by the irradiation with visible light. In this regard, the combination of transition metal catalysis and photochemistry is a breakthrough in catalysis that has provided impossible...

Multifunctional Flexible Laser-Scribed Graphene Sensors for Resilient and Sustainable Electronics

Altynay Kaidarova
The Fourth Industrial Revolution is driven by cyber-physical systems, in which sensors link the real and virtual worlds. A global explosion of physical sensors seamlessly connected to networks is expected to produce trillions of sensors annually. To accommodate sustainable sensor production, it is crucial to minimize the consumption of raw materials, the complexity of fabrication, and waste discharge while improving sensor performance and wearability. Graphene has emerged as an excellent candidate material for its electrical...

Electrification and Wetting at Water–Hydrophobe Interfaces: Fundamentals and Applications

Jamilya Nauruzbayeva
Interfaces of water with water-repellent, or hydrophobic, materials are relevant in numerous natural and applied contexts. Examples include lotus leaves, membranes-assisted separation processes, and oil–water emulsions. Typically, water repellence is realized with the help of hydrocarbons and perfluorocarbons. Although these materials present low adhesion to water, their interfaces with water are known to be electrically charged. Origins of the electrification of water–hydrophobe interfaces is a century-old mystery that has been intensely debated on. A number...

Cellular and Polymeric Membranes for Separation and Delivery Applications

Mram Z. Alyami
The primary focus of this research is to utilize cellular and polymeric membranes for biomedical applications: To date, several organic and inorganic materials have been used to synthesize nanoparticles (NPs). The question arises as to which criteria and design principles should be considered while selecting the best material. Based on the results of testing, three key roles of NPs have been identified. First, NPs need enough circulation time to reach their target. Then these NPs...

Sunlight Modulation for Optical Wireless Communication

Sahar Ammar
Solar energy is widely used for electricity generation, heating systems, and indoor environment daytime illumination. Indeed, large amounts of Sunlight energy remain insufficiently used. In this work, we aim at employing sunlight for data transmission as another option for wireless communications. Being emitted by an uncontrollable source, taming the Sunlight is a challenging task that requires appropriate technolo- gies to manipulate incident light. Throughout this thesis, we first review switchable glass technologies and investigate their...

Bioaugmentation as a Strategy to Engineer the Anodic Biofilm Assembly in Microbial Electrolysis Cell Fed with Wastewater

Mohammed A. Bader
Microbial electrolysis cell (MEC) system is a potential technology that could treat wastewater while simultaneously generating H2 (green energy). MEC's electroactive bacteria (EAB) are essential microbes responsible for oxidizing organic pollutants (such as acetate) in wastewater using an electrogenesis process. Since EABs comprise the core of MECs, they are essential for maintaining functional stability (Coulombic efficiency (CE), current density, and pollutant removal) of MECs. The cause of EAB becoming dominant at the anode of MECs...

Control Design for Alignment Problem in Optical Wireless Communication

Asem Ibrahim Alwan Al-Alwan
Optical wireless communication (OWC) offers many benefits over established radio frequency–based communication links. Particularly in, high-data services, high security, and license-free operation, OWC link are becoming an attractive solution for the next generation of communication systems. In OWC, precise alignment of the incoming beam is necessary to close the communication link. However, precisely aligning the beam between the transceivers is challenging due to the laser beam’s narrowness and external disturbances that can significantly reduce, destroy,...

Optical Behavior of Perovskite Nanocrystals with Different Dimensionalities

Haoze Yang
Metal halide perovskites have rapidly gained researchers’ attention and become one of the most promising materials today, with exciting properties and multiple optoelectronic applications. Regardless of the shape into which perovskite materials have been fashioned, the nanocrystals that constitute these materials have been the object of extensive research. Perovskite nanocrystals (PNCs) have rapidly developed due to their favorable optical and electronic properties, including high photoluminescence quantum yield, narrow emission bands, and tunable optical band gap....

mm-Wave Radar-Based Indoor and Outdoor Parking Monitoring and Management

Yingquan Li
Multistory parking can accommodate a maximum number of vehicles in a limited space. However, in multistory and outdoor busy parking, it becomes challenging for drivers to find free parking slots, and they have to search in different parking lanes and floors. This results in the wastage of fuel and time and contaminates the atmosphere. To address this issue, the state-of-the-art solution exploits an optical sensor to detect if a car is present in the parking...

Terahertz-Band Ultra-Massive MIMO Data Detection and Decoding

Hakim Jemaa
As the quest for higher data rates continues, future generations of wireless communications are expected to concur even higher frequency bands, particularly at terahertz (THz) frequencies. Even though the vast bandwidths at the THz band promise terabit-per-second (Tbps) data rates, current baseband technologies do not support such high rates. In particular, the complexities of Tbps channel code decoding and ultra-massive multiple-input multiple-output data detection are prohibitive. This work addresses the efficient data detection and channel-code...

On the Formation of Hydrogen Peroxide in Water Microdroplets

Nayara H. Musskopf
Recent reports on the formation of hydrogen peroxide (H$_2$O$_2$) in water microdroplets produced via capillary condensation or pneumatic spraying have garnered significant attention. How covalent bonds in water could break under such conditions challenges our textbook understanding of physical chemistry and the water substance. While there is no definitive answer, it has been speculated that ultrahigh electric fields at the air-water interface are responsible for this chemical transformation. This thesis documents the findings of our...

Check Your Other Door: Creating Backdoor Attacks in the Frequency Domain

Hasan Abed Al Kader Hammoud
Deep Neural Networks (DNNs) are ubiquitous and span a variety of applications ranging from image classification and facial recognition to medical image analysis and real-time object detection. As DNN models become more sophisticated and complex, the computational cost of training these models becomes a burden. For this reason, outsourcing the training process has been the go-to option for many DNN users. Unfortunately, this comes at the cost of vulnerability to backdoor attacks. These attacks aim...

In Situ Formation of Grafted Silica Nanoparticles with Poly(Methyl Methacrylate)-Based Block Copolymers

Noor H. Albarbari
Silica (inorganic)-g-polymer (organic) hybrid materials with a large variety of functionality have been studied intensively because of the improvement in their physical and chemical properties (e.g., thermal, mechanical, electrical, magnetic properties, etc.) with respect to conventional organic and inorganic materials. 1–3 This research work introduces a new strategy based on in situ formation of poly(methyl methacrylate) block copolymer grafted silica nanoparticles. The thesis is divided into two major parts. In the first part, the atom...

Polyethylene Grafted Silica Nanoparticles via Surface-Initiated Polyhomologation: A Novel Filler for Polyolefin Nanocomposites

Reem D. Alghamdi
Silica nanoparticles (SiO2 NPs) were prepared and functionalized with polyethylene (PE@SiO2 NPs) using the surface-initiated polyhomologation (SI polyhomologation) technique. Polyolefin nanocomposites were fabricated later by melt mixing of different ratios of the as-prepared SiO2 NPs and PE@SiO2 NPs with linear low-density polyethylene (LLDPE) and low-density polyethylene (LDPE) matrices. Firstly, SiO2 NPs were modified with different alkoxysilane ligands, dichloro(divinyl)silane (DCDVS), allyl trimethoxysilane (ATMS), and vinyl triethoxylsilane (VTES). Subsequently, thexylborane, an initiator for SI polyhomologation, was immobilized...

Underwater Optical Communication and Sensing Technology in Silent Ocean

Yujian Guo
Oceans cover 71% Oceans cover 71% surface of the earth and are rich in oil and gas resources, marine living resources, renewable energy, mineral resources. The depths of the oceans are often thought of as a silent world, but that was never the case, and oceans have become noisier as human technologies have advanced. Humans have not only added noise to the ocean; they have also eliminated natural sounds. One of the primary noise sources...

Investigation of heterologous expression of the non-ribosomal peptide blue pigment synthase and its activator from the nuclear genome of the model microalga Chlamydomonas reinhardtii

Manar Shlbi
The non-ribosomal peptide synthase (NRPS) blue pigment synthase (BpsA) has been shown in several heterologous hosts to mediate the production of the blue pigment indigoidine from two molecules of L-glutamine. Activation of BpsA is mediated by transfer of a coenzyme A (CoA) by a 4′-phosphopantetheinyl transferase (4′-PPTase). In this thesis, I explored heterologous co-expression of BpsA and the Pseudomonas aeruginosa 4′-PPTase (PaPcpS) and their co- localization to either cytoplasm or chloroplast stroma of the green...

A Decentralized Approach to Human-Robot Object Transportation Through the Control of a Catenary Cable

Juman AlAbdullatif
An important challenge for human-robot interaction is for both the human and the robot to agree on a model of motion. However, most applications require machine learning and heavy communication for the robot to be an active member in executing a joint task and adapt to human behavior. In this work, we develop a decentralized approach to control and track a catenary cable for object transportation in a human robot interaction scope. Our system is...

Laser-Scribed Graphene Electrochemical Sensors for Health Applications

Tutku Beduk
Electrochemical sensing platforms including nanostructured materials have attracted increasing attention for diagnostic applications in recent decades. People in resource-limited places, particularly in low- and middle-income countries, continue to face problems finding high-quality medical treatment and technologies. This thesis aims to create affordable electrochemical-based point of care (PoC) diagnostic systems using laser-scribed graphene (LSG) material as the sensing platform. The use of LSG sensors for diagnostic purposes has been gaining attention. Compared to established methods for...

Experimental and Theoretical Investigation on the Temperature-dependent Optical Properties of Hybrid Halide Perovskites

Ohoud K. Alharbi
Nowadays, studying materials for renewable energy applications are highly de- manded. Hybrid halide perovskites have proven to be promising materials for such technology since their first application in solar cells in 2008, with a power conversion efficiency of 2.7%. Since then, hybrid halide perovskites have proven their superior properties for light-absorbing devices. In this scope, studying the optical properties is ultimately essential. This work investigates the tempera- ture dependence of the optical spectra for formamidinium...

Synthesis and characterization of self-assembling peptides and depsipeptides for use in tissue engineering and in aqueous zinc batteries

Xinzhi Liu
Self-assembly is an autonomous process where components organize themselves into structures via noncovalent interactions without human intervention. Ultrashort amphiphilic peptides are typical self-assembly molecules with specific sequence motifs which consist of three to seven amino acids. Due to their amphiphilic structure which carries a dominant hydrophobic tail and a polar head group, these peptides can self-assemble to construct nanofibrous scaffolds system to form hydrogels, organogels or aerogels. The nanofibrous scaffolds formed by amphiphilic peptides are...

De novo genome-scale prediction of protein-protein interaction networks using ontology-based background knowledge

Kexin Niu
Proteins and their function play one of the most essential roles in various biological processes. The study of PPI is of considerable importance. PPI network data are of great scientific value, however, they are incomplete and experimental identification is time and money consuming. Available computational methods perform well on model organisms’ PPI prediction but perform poorly for a novel organism. Due to the incompleteness of interaction data, it is challenging to train a model for...

Synthesis, Modification, and Evaluation of MXene as a Novel Anode Electrode Material for Bio-electrochemical Systems

PEWEE DATOO KOLUBAH
Bioelectrochemical systems (BESs) show promising prospects for recovering energy and chemicals from industrial and municipal wastewater. Despite the advances in the development of this technology, there is still a significant need for efficient electrode materials with high conductivity, hydrophilicity, and good biocompatibility to boost their performance and increase productivity. In this work, metal nanoparticle-two-dimensional MXene (W2N-Ti3C2Tx and Fe-W2N-Ti3C2Tx) composite electrocatalysts were synthesized using a simple impregnation method and deposited on carbon cloth (CC) to be...

Sars-Cov-2 Intra-Host Evolution in Immunocompromised Patients for the Emergence of Variants of Concerns, Including Omicron.

Azari I. Bantan
Unexpected high mutations detected in new emerging variants of concern (VOCs) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), especially in the case of omicron, raises concerns and efforts to understand their evolutionary trajectory. Several hypotheses have been discussed in literature to conceptualize the source of their emergence, including intra-host viral evolution in immunocompromised patients. These patients grant opportunities for the emergence of new variants through a persisting virus winning against host immunity, and selection...

Water Effect on the Methanol to Olefin Conversion over SSZ-13 Catalyst with an Operando Spectroscopy

Mohammed Alsindi
For more than 50 years, the methanol to olefins (MTO) reaction remains to be a hot topic within the catalysis community. The recent discoveries about it and the industrial implementation made it even receive more attention. The best way this process can be used is by hydrogenation of CO2 to make methanol and undergo after that the MTO reaction. This method will save energy, be more environmentally friendly, and be sustainable, but it requires advancement...

Registration Year

  • 2022
    580

Resource Types

  • Dissertation
    568
  • Dataset
    9
  • Other
    3

Affiliations

  • King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia
    572