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Silver nanoparticles-loaded titanium dioxide coating towards immobilized photocatalytic reactor for water decontamination and bacterial deactivation under natural sunlight irradiation
The environmental implications of rapid industrialization, including rising pollution, depleted resources, the effects of climate change brought on by global warming, and unrestrained groundwater extraction, are contributing to a growing water scarcity crisis [1-3]. The improvements in quality of life are largely attributable to the innovations in manufacturing technology made possible by the Industrial Revolution, but these innovations also pose risks to the natural world and human health [1-3]. The textile business uses a wide variety of raw materials, including natural fibers like cotton as well as synthetic and woolen fibers, and the chemical components of dyes are just one example. The annual output of synthetic dyes is around 700,000 tons, and there are over 10,000 different varieties available. As much as 200,000 tons of synthetic dyes are released into the environment every year due to the inefficient dyeing technique commonly employed in the textile industry. According to the World Bank, the processing of textiles for dyeing and finishing accounts for between 17 and 20 percent of industrial wastewater [1-3]. Textile wastewaters contain a high biological oxygen demand (BOD), chemical oxygen demand (COD), nitrogen, color, acidity, high suspended particles, high dissolved solids, surfactants, dyestuffs, heavy metals, and other soluble chemicals [3] due to the variety of dyes used to color textile items. In particular, water-soluble reactive and azo dyes are employed to obtain the required color. Ten to twenty percent of the dyes used end up in the effluents, where they might harm wildlife and the ecosystem (carcinogenic or mutagenic). Headaches, nausea, skin irritation, respiratory difficulties, and congenital deformities are only some of the health problems linked to exposure to textile wastewater. There are repercussions for aquatic ecology, environmental biodiversity, and the quality of receiving water bodies. New, low-cost, and highly effective water treatment methods are needed to deal with polluted wastewater. Adsorption and coagulation, two common water purification methods, just concentrate pollutants by shifting them to other phases; they do not "eliminate" or "destroy" them. Sedimentation, filtration, chemical oxidation, and biotechnology are all examples of conventional water treatment methods, but they all have their drawbacks. These include insufficient removal, high chemical reagent consumption, high treatment costs, long treatment times, and the creation of toxic secondary pollutants. New water treatment procedures are needed to improve the quality of treated effluent [1-3]. The use of semiconductor particles in photocatalysis is gaining appeal as a solution to global pollution problems due to its shown efficiency in degrading a wide variety of contaminants. Photocatalyst-coated surfaces-based reactors have proven to be practical for long-term operation over photocatalytic powder-based reactors (i.e., slurry-based reactors) [4-5]. As a promising photo-electrode and photocatalyst, titanium dioxide (TiO2) has enjoyed wider applicability in photocatalytic hydrogen generation, solar cells, and remediation of organic contaminants among other photo-catalytic applications [4-6]. TiO2 has been recognized as one of the low-cost, most effective, and fascinating photo-catalyst as a result of its interesting thermal and chemical stability, desirable electronic features, others, and environmental benignity [6-8]. Pristine TiO2 semiconductor is characterized by a wide band gap that can only utilize the UV part of the light spectrum with a wavelength of less than 385 nm, which is just 5% of the sunlight energy capacity. Spectrum usability extension to visible regions warrants further and extensive research study [8-10]. Additionally, the quickness of the recombination of photo-generated holes and electrons further restricts the practical applicability of the semiconductor [10-12]. It is highly desirable to develop a cost-effective scalable strategy to over these drawbacks toward sustainable development and a clean environment using only natural sunlight irradiation [5-11]. In addition, it is preferred to fabricate them as films rather than powders as photocatalytic immobilized reactors are more practical than powder-based reactors [4-8]. Dye sensitization, supports, magnetic separation, and surface modification by doping with non-metals, metals, and transition metals and coupling with other semiconductors have all been used to enhance the photocatalytic activity of TiO2 photocatalyst. Higher photonic efficiency can be attained through the synergistic fine-tuning of features such as physical, chemical, and electronic, and these composites and hybrid materials based on TiO2 are creating a big trend. Doping has been widely studied as a means of altering the surface of TiO2. Rare earth metals, noble metals, and transition metals are all discussed in the existing literature on the surface modification of TiO2 doped with cations [4-12]. In this study, for the first time, Ag nanoparticles loaded mesoporous TiO2 coating was prepared and applied as an immobilized photocatalytic reactor for water decontamination and bacterial deactivation under natural sunlight irradiation.
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Developing a Heart-Rate Monitoring App to Help Families in Identifying Mood Changes for Children Diagnosed With Neurodivergence
This study dives into the benefits of a heart rate (HR) monitoring application to aid families in identifying mood changes in children diagnosed with neurodivergence. Children with neurodivergence often struggle with communicating their emotions, which often results in tantrums or emotional outbursts, and this study plans to address this by creating an app that detects users’ HR to calculate heart rate variability (HRV) and detect when the user’s heart rate variability (HRV) levels become higher than usual. Heart-rate variability is defined as a small variation of the interval between every heartbeat, it’s calculated with the formula of . By looking at the developments of these small variations, it will be 60/𝐵𝑃𝑀 × 1000 easier to notice then the interval for heartbeats are shorter, meaning the body is in need of more blood pumped quickly for support. The app is connected to a heart rate sensor that is worn by the user. The heart-rate sensor frequently uploads data to the app which the app processes and carefully observes while looking for any sudden, dramatic change. The sensor and app was tested and proved to meet the expected requirements of functionality. Four participants with neurodivergence were asked to equip the heart-rate sensor and results showed that different developments of heart-rate variability were able to be detected by the app, these participants varied in their type of neurodivergence as well as their age. As an example, the third participant showed the purpose of the app most visibly, having a resting heart-rate of 86 BPM (697.67 ms) turning into a high 107 BPM (561.68ms) after changing activities. When the user’s sensor detects a sudden spike in heart-rate variability, the app notified the parent account about this change in emotion. This study has supported the relevance of using heart-rate variability to observe changes in mood.
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In the first part of this project, distilled water and 95% ethanol were used to extract ultra-violet(UV)-absorbing and anti-oxidizing compounds from different types of algae including kelp, wakame, sea grape and nori. Activated charcoal was used in attempt to purify the extracts and removed excessive pigments. It was found that the charcoal was more effective in adsorbing pigments from ethanol extract in which up to 80 to 100% pigments could be removed. The UV-absorbing and anti-oxidizing properties of the algae extracts were also studied. All algae extracts showed significant UV-absorbing and anti-oxidizing properties. In particular, extract formed by using 3 g kelp powder in distilled water could significantly reduce 50% UV intensity and react 96.5% DPPH solution which acts as a source of free radicals. In the second part of the project, three applications of algae were explored in details. Firstly, it was found that kelp, wakame and nori extracts by using over 2 g of algae in 30 mL olive oil could absorb UVA and UVB by over 90%, which is comparable to the performance of zinc oxide, a common ingredient in commercial sunscreen products. Costs of preparing the sunscreens were also compared. Except for wakame extract, all other extracts were cheaper than using zinc oxide. Moreover, the kelp extract was found to maintain its UV- absorbing and anti-oxidizing abilities after at least 30 days of storage under room conditions. Lastly, sodium alginate was successfully extracted from kelp with a product yield up to 30%. The alginate solution was then used to form a calcium-alginate protective coating on plastic slides to reduce UV intensity by up to 50%. This aims to apply on nails or fingers during UV nail gel polish to protect against UVR.
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Development of Oil Collecting Submarine using AI and hydrophobic solution
Such as the plastic waste and industrial discharge that permeate our oceans, it is the insidious and infamous nature of oil spills that demands our immediate attention. These spills, with their far-reaching ecological ramifications, pose a profound danger to our marine ecosystems, demanding urgent action and a heightened awareness of the true menace that is caused by this oil
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Breaking a Caesar Cipher / Vigenère Cipher Encryption for Secure Data Communication
This project had one purpose: creating almost unbreakable encryption by breaking a Caesar – and Vigenère Cipher and getting familiar with how they work. Created a program to encrypt and decrypt messages with a Caesar Cipher and Vigenère Cipher encryption. Breaking these encryptions in these programs will help to identify the factors that contribute to strong and weak encryption systems. A program was created to encrypt messages using Caesar Cipher with a key from 1 to 25 and decrypt messages without knowing the original key by doing different types of “attacks” on the system: a brute force and frequency analysis attack. Created another program to encrypt messages using Vigenère Cipher with a keyword or keyphrase and decrypted messages whilst knowing that original keyword. Tested and compared the two different cyphers when being attacked. This helped identify factors that influenced the strength of encryption and identified the advantages and disadvantages of each Cipher as well as the weaknesses in each attack. Through testing and breaking a Caesar and Vigenère Cipher successfully, multiple factors were identified that influenced the strength of the encryption system. These were used to ensure the new encryption created will be as strong as can be. Comparing the success rate of the different attacks on each Cipher, the similarities, weaknesses and strengths in the Brute Force and Frequency Analysis attacks were found.
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Desert to Fertile Land: Developing TEPA‐modified montmorillonite clay as an efficient CO2 adsorbent to enhance soil fertility
Global warming is a phenomenon in which the Earth's overall temperature rises as a result of increasing concentrations of greenhouse gases in the atmosphere. Among the major greenhouse gases, carbon dioxide (CO2) is the primary greenhouse gas that contributes significantly to global warming [1,2]. The concentration of carbon dioxide in the atmosphere is rising due to human activities such as burning fossil fuels (coal, oil, natural gas), as well as changes in land use and vegetation [3]. Carbon dioxide and other gases, such as methane and nitrogen monoxide absorb infrared radiation and redirect it back to Earth, warming the planet [4]. This rise in temperature can impact ecosystems, climate, water resources, agriculture, public health, and societies in general [5]. To combat global warming and reduce carbon dioxide concentrations in the atmosphere, many countries around the world, including Saudi Arabia, are working to achieve a vision to reduce carbon emissions by reducing their carbon emissions by 278 million tons per year by 2030 in line with the Paris Agreement, for climate. The Kingdom is committed to generating 50% of its electrical energy from renewable sources by 2030. In addition to the shift in the local energy mix, the Saudi Green Initiative is implementing a number of ambitious programs and projects to reduce emissions. These programs include investing in new energy sources, promoting energy efficiency, and expanding carbon capture and storage programs [6]. Through these initiatives, the Kingdom will be able to achieve its climate goals and establish a sustainable future (Figure 1). In addition, the Paris Climate Change Agreement includes 196 countries and the European Union, covering most of the world. This agreement aims to achieve carbon neutrality by taking measures to reduce carbon dioxide emissions [7].
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King's Power - The Utilization of Agricultural Waste in the Production of Sustainable Dry Cells
The idea of dramatically reducing the cost of the production dry cell, reducing its carbon footprint, and being able to be an alternative to current materials such as biochars really propels the interest of performing this project research. Biochars from durian husk, bamboo and coconut shell are promising alternative chemical materials of the anodes in the dry cell due to their eco-friendly traits and availability in the trophic areas which covers about 40% of the land on earth. Using the technique of pyrolysis, the latest and the best technique to produce a high carbon content biochars, the dry cell uses the potassium hydroxide as the electrolyte and manganese dioxide as the catalysts that make the biochar mixture to produce maximum voltage of 65% from the dry cell sold in the current market. The voltage analysis of the biochar dry cell was done in our school science laboratory and then, characterization tests analysis was carried out on the products from the specific biomass namely the SEM/EDX analysis, at the Material Characterization Laboratory (MCL), Department of Chemical and Environmental Engineering, Faculty of Engineering, University Putra 馬來西亞. Based on our research, the biochar obtained from the raw materials (Durian Husk, Bamboo and Coconut Shell) had shown different characteristics. The bamboo biochar had shown the most amount of carbon content which is 86.64% more than the durian husk biochar (72.77%) and coconut shell biochar (65.57%). On the other hand, based on the micrograph, we observed that the durian husk biochar had shown much created pores rather than bamboo biochar and coconut shell biochar. In our study, we found out that the average voltage produced by the three different biochars have shown that Durian Husk char dry cell produced the highest voltage which is 0.97V, more than the bamboo char (0.62V) and coconut shell char (0.73V). In conclusion, the biochar dry cell produced are much cheaper in term of its production as our biochar dry cell uses biomass that are freely available and comes from renewable source of energy, the best ingredient for Green Technology.
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Inclined Sedimentation of Suspensions: Theoretical and Experimental Investigation into the Boycott Effect
The Boycott Effect is a phenomenon where sedimentation rate can be increased by tilting the container which holds the suspension, making it a way to increase the efficiency of the process without additional energy input. This makes the Boycott Effect valuable in speeding up and optimising a multitude of industrial applications such as wastewater management and food processing, all of which employ sedimentation to separate particulate matter from the fluids in which they are suspended in. Thus, it is imperative to model the Boycott Effect accurately for a wide range of cases, including arbitrary shaped containers and suspensions of various concentrations without the need to run costly, computationally expensive numerical simulations. In this project I investigated the inclined sedimentation of suspensions both theoretically and experimentally. Experimentally, two image tracking programs were created and tested out on my own experimental videos. I demonstrated the use of a novel method for making use of the Beer-Lambert Law to optically keep track of local concentration of suspensions. This method allows more information to be gathered about the sedimentation process in a very low-cost, non-equipment intensive or invasive way. Theoretically, I expanded upon the well-known analytical 2D PNK theory by accounting for concentration-hindering and sediment build-up effects, as well as the geometrical theory for 3D cylindrical geometries. All parts of the theoretical model were verified with experimental data and shown to have good agreement. (233 words)
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Development of Electrical Shielding system for auto dust removal for solar PV modules
Currently, Large-scale solar PV systems installations are taking place in the desert environment and space to harness abundant solar energy effectively. Dust accumulation on the surface of photovoltaic panels (PV) is the most stignant problem for photovoltaic panels, as dust deposition reduces PV problem energy generation efficiency significantly. Thus, the removal of dust from the PV panels has become very important to increase the rate of energy efficiency by the PV panels. The dust particles could be reduced using traditional dust cleaning techniques. But, in the harsh and hostile desert environment, these approaches which requires a lot of water, complicated mechanical instruments, enormous logistics, and personnel. Electrodynamic dust shielding (EDS) system has been developed at our laboratory to remove dust particles from the surface of the PV panels. The EDS system has been successfully tested for dust mitigation. The unique features of our EDS System is that it is cost effective, easy to install and no manpower required as it is an unmanned system. The design and construction of a single-phase electrodynamic dust repulsion device built locally in KSA is demonstrated in this study. This work showed that the optimized electrode design and electrical parameters, such as AC source voltage and frequency, maximized the EDS system's dust mitigation effectiveness. A perfect balance was achieved between the geometrical and electrical parameters of the EDS system, resulting in a dust removal efficiency of up to 92±1 ℅.
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Non-Invasive Vagus Nerve Stimulation as a Novel Therapy for Alzheimer’s Disease by Enhancing the Brain Clearance System(非侵入性迷走神經刺激術作為阿茲海默症的新療法—透過增強大腦清除系統)
阿茲海默症(AD)是導致失智症的主因,影響全球數千萬人。然而,AD目前的藥物大多昂貴且療效有限。目前已知腦內β類澱粉蛋白(Aβ)斑塊為AD的病理特徵,且大腦清除系統被認為對AD的治療具有重要性。先前研究發現非侵入性迷走神經刺激術(nVNS)增加腦脊髓液循環,但在神經退化疾病中的機制和應用尚不明確。本研究旨在探討nVNS增強大腦清除系統來作為AD新療法之成效,使用Aβ誘導之AD小鼠模型,利用巨視顯微鏡和免疫組織化學染色評估其膠淋巴系統功能,並以新奇事物測試評估認知功能。本研究發現於AD小鼠中,給予nVNS使大腦清除系統之水通道蛋白-4顯著增加、促進膠淋巴系統,進而改善認知功能。本研究首次發現nVNS可通過增強大腦清除系統功能,進而改善AD病理引起的失智症狀,支持nVNS作為AD新療法的可行性。
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Application of Carbon Aerogels in Lithium-Air Batteries
One of the main challenges with today’s batteries is their relatively low volumetric and specific capacities. The highest specific capacity can be achieved with lithium-air batteries, which use metallic lithium as the anode and typically some form of porous carbon as the cathode. To enhance performance, aerogels—among the world’s lightest solid materials—are ideal candidates for cathodes. Resorcinol-formaldehyde (RF)-based carbon aerogels, for example, serve this purpose well. In my work, I utilized two types of carbon aerogels as cathode materials: one derived from pyrolyzed resorcinol-formaldehyde polymer and the other a graphene-oxide-modified version of this carbon gel. I integrated the carbon aerogels I had pyrolyzed into lithium-air batteries to improve the cell’s performance, energy density, and capacity compared to cells using activated carbon. In my research, I examined the pore structure and surface properties of these materials in aqueous media using NMR (nuclear magnetic resonance) relaxometry and cryoporometry, exploring their impact on battery efficiency. I found that the graphene-oxide-containing sample's pores filled with water in a layered manner, indicating a more hydrophilic surface, which suggests a denser arrangement of oxygen-containing functional groups compared to the unmodified carbon aerogel. The pore sizes were reduced after adding graphene oxide, resulting in an increased specific surface area for the sample. Incorporating the reduced graphene-oxide-containing carbon aerogel enabled the creation of a more efficient, higher-capacity battery than with the RF carbon aerogel. This improved performance is likely due to the aerogel’s higher oxygen content and altered morphology. The increased oxygen content provides more active sites for oxygen reduction, meaning that a greater specific power output can be obtained from the battery.
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Trojan Horses in the Fight against Skin Cancer
In photodynamic therapy (PDT), reactive oxygen species are generated within the cytoplasm to destroy cancer cells selectively. Using porphyrinic structures (PS) as photosensitizers holds promise for targeting cancer cells. However, direct incorporation of the porphyrins into cancer cells remains elusive. Hence, Dr. Martina Vermathen’s research introduced specific membranous phospholipid nanocarriers for topical porphyrin applications. However, since a sufficiently high enough concentration of PS in cancer cells has not yet been achieved, this study aimed to improve skin uptake of the nanocarriers. Two approaches were examined: (1) comparing polar and nonpolar porphyrins and (2) assessing the effect of a penetration enhancer, DMSO, through a neat and diluted application. The polarity of the porphyrins was first quantified with a log P test. The nanocarriers were assembled by incorporating two different PS compounds, either the mono- or tetra-4-carboxy substituted phenyl porphyrin. They were then characterized by 1D and 2D-NMR analysis. The porphyrin permeation was tested by Franz diffusion tests on pig ear skin. For the second approach, DMSO was added in the Franz diffusion test, either directly applied on the skin (“neat“) or diluted in the nanocarriers (“diluted”). The log P test for the mono- and the tetra-carboxyphenyl porphyrin resulted in values of 4.5 and -1.1, respectively. The more polar tetra-carboxyphenyl porphyrin exhibited 2.8 times better skin uptake compared to the mono-carboxyphenyl porphyrin. The neat DMSO application increased uptake by a factor of 5.5. The diluted DMSO application worsened skin uptake slightly. Analytical techniques revealed differences in porphyrin encapsulation: The mono-carboxyphenyl porphyrins were encapsulated in the centre, whereas tetra-carboxyphenyl porphyrins were localised around the nanocarriers. Results indicated potential instability of the nanocarriers. The more polar tetra-substituted porphyrins showed superior skin diffusion than the mono-substituted derivative. The neat DMSO application facilitated enhanced skin uptake by inducing membrane destabilization and pore formation but may have limited applicability. Further research is suggested to explore porphyrinic PS with alternative polar substitution patterns and tailored penetration enhancers for lipid-based delivery systems. Overall, the study underscores the importance of molecular properties of the PS system and demonstrates the potential of penetration enhancers in optimizing PDT for skin cancer treatment.
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