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Preparation And Characterization Of Niti/Pva Nanofibers By Electrospinning, Akram Jabur, Randa Al-Tuhafi Jul 2026

Preparation And Characterization Of Niti/Pva Nanofibers By Electrospinning, Akram Jabur, Randa Al-Tuhafi

Engineering and Technology Journal

NiTi alloys are widely used in biomedical applications for their unique properties particularly the shape memory effect, superelasticity, and biocompatibility. In this research, NiTi/PVA composite nanofibers are fabricated by electrospinning technique, using a novel method of producing NiTi ultrafine particles by immersing amorphous NiTi alloy in dilute aqua regia solution. The NiTi particles are successfully embedded in the PVA matrix. The produced NiTi particles are analyzed by X-ray diffraction (XRD), Energy dispersive spectroscopy (EDS), and Particle size analyzer. The XRD pattern of ultrafine NiTi particles shows much better phases as compared to the XRD pattern of the amorphous NiTi alloy …

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Preparation Of Graphene Nanosheets From Graphite Flakes Via Shear Assisted Exfoliation, Ali Saloum, Basma Al-Tamimi, Saad Farid Jul 2026

Preparation Of Graphene Nanosheets From Graphite Flakes Via Shear Assisted Exfoliation, Ali Saloum, Basma Al-Tamimi, Saad Farid

Engineering and Technology Journal

Graphene is one of the most important forms of carbon. Due to its exceptional physical, chemical, and mechanical properties, it’s used in different fields such as electronic, energy storage, and medical applications. Therefore, the production of graphene in large quantities, at a low cost, and high quality, has become critical. Using graphite powder, a few layers of graphene sheets were prepared via a series of mechanical exfoliation methods. the dry ball milling process by the planetary mill was used. Thereafter, the milling was followed by shear force and then supported by ultra-sonication to reach the lowest level of the graphene …

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Wild Clary Plant Extract As Corrosion Inhibitor For Carbon Steel In Seawater Medium, Zainab Aziz, Rana Majed, Majid Abd Jul 2026

Wild Clary Plant Extract As Corrosion Inhibitor For Carbon Steel In Seawater Medium, Zainab Aziz, Rana Majed, Majid Abd

Engineering and Technology Journal

Aqueous extract of wild clary has been used in place of a corrosion inhibitor in the corrosion control of carbon steel. The major components of this extract are Ethan amine, Amino-octadic, and 4H-Pyran-4-one. It has an excellent inhibition efficiency (IE) of 83.078% at a concentration of 20 (mL/L) and a temperature of 298 (K). The extract was characterized by FTIR and GC MS, where the antibacterial was tested and the protective film was analyzed on the samples using FTIR spectra. The protective film formed on the metal surface is confirmed using an electrochemical study by Potentiostat, which revealed that this …

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Recycling Of Wood – Plastic Composite Prepared From Poly (Ethylene Terephthalate) And Wood Sawdust, Halla Shehap, Mohammed Alzuhairi, Sarmad Ibrahim, Saif Hussien Jul 2026

Recycling Of Wood – Plastic Composite Prepared From Poly (Ethylene Terephthalate) And Wood Sawdust, Halla Shehap, Mohammed Alzuhairi, Sarmad Ibrahim, Saif Hussien

Engineering and Technology Journal

Plastic waste has become one of the humanities and the ecosystem balance serious environmental Challenges. Furthermore, it is the primary source of plastic pollution because it is inexpensive, widely available, and frequently discarded. Using various waste materials and side fractions as part of wood-plastic composites is one way to promote the circular economy (WPC). Several environmental benefits can be realized by using recycled plastic, including extending the usable life of plastic, reducing waste, contributing to the development of trash recycling, and preventing resource depletion. One of the most efficient recycling processes is glycolysis; the (PET) is depolymerized by ethylene glycol …

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A Visual Enhancement Quality Of Digital Medical Image Based On Bat Optimization, Kholood Hussin, Ali Nahar, Hussain Khleaf Jul 2026

A Visual Enhancement Quality Of Digital Medical Image Based On Bat Optimization, Kholood Hussin, Ali Nahar, Hussain Khleaf

Engineering and Technology Journal

Improve medical image visualization is a critical preliminary step before further imagery processing like analyzing texture, extracting features, and segmentation. Imagery noises in medical images are frequently occurred as a consequence of different artificial processes such as acquisition, sending and receiving, and storing & retrieving processes. As a result, the quality of image visualization is degraded. Therefore, a de-noise process is important in order to maintain good image quality for medical purposes. In this paper, medical image enhancement aims to de-noise as much as possible while maintaining detailed features and edges. This work employed an optimization algorithm called "Bat" to …

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A Study Of Patient’S Pain Assessment Based On Facial Expression: Issues And Challenges, Elaf Saddam, Saad Mutashar, Wissam Ali Jul 2026

A Study Of Patient’S Pain Assessment Based On Facial Expression: Issues And Challenges, Elaf Saddam, Saad Mutashar, Wissam Ali

Engineering and Technology Journal

Pain is considered as an emotional experience and a restless feeling associated with tissue damage. When the interpretation begins in the brain, the sensation of pain occurs; a signal transmitted to the brain through the nerve fiber. Pain helps the body to stop further damage to the tissues. Since there are numerous ways to convey and feel pain, the perception of pain is special to all. Technology that promotes pain assessment is an urgent need to reduce restless feelings and suffering. This paper aims to demonstrate the issues and challenges facing the patient’s pain assessment based on facial expression. The …

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Signaling Load Reduction In 5g Network And Beyond, Mohammed Waheed, Azzad Saeed, Thanaa Abd Jul 2026

Signaling Load Reduction In 5g Network And Beyond, Mohammed Waheed, Azzad Saeed, Thanaa Abd

Engineering and Technology Journal

A huge traffic flow in the next generation network is anticipated due to the rising in number of users and the new services that need low end-to-end latency causing a large signaling load on the Core Network (CN). In order to mitigate this issue, many revolutionary architectures have been proposed to reduce this burden such as Cloud Radio Access Network (C-RAN). In this paper, a new C-RAN distributed core network architecture has been proposed by splitting some CN functions and grouping them into one location with Base Band Units (BBUs). As a measure of testing the proposed architectures and by …

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Chitosan Hydrogel For Removing Of Heavy Metal Ions From Water: A Review, Maysaa Ali, Shemaa Soud, Anaheed Hameed Jul 2026

Chitosan Hydrogel For Removing Of Heavy Metal Ions From Water: A Review, Maysaa Ali, Shemaa Soud, Anaheed Hameed

Engineering and Technology Journal

Industrial and agricultural discharges have been shown as important sources for a wide range of contaminants like heavy metals. This study focused on the assessment of the toxic effect of heavy metals and illustrates some methods of eliminating or avoiding these contaminants. In certain methods, heavy metals (Cu, Zn, Cr, Ni, Pb, Hg, and Cd) are recovered, and range of absorbents are tested. A number of studies have reported the complex interaction of polymers with metal ions with the polymers for eliminating heavy metals (e.g. cellulose, chitosan, and chitin. Metal ions are absorbed by these polymers by the amine and …

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An Experimental Study Of Porous Hydroxyapatite Scaffold Bioactivity In Biomedical Applications, Auday Mehatlaf, Alaa Atiyah, Saad Farid Jul 2026

An Experimental Study Of Porous Hydroxyapatite Scaffold Bioactivity In Biomedical Applications, Auday Mehatlaf, Alaa Atiyah, Saad Farid

Engineering and Technology Journal

Hydroxyapatite is one of the most bioactive materials used in tissue engineering due to its excellent biocompatibility and chemical composition which is equivalent to the mineral element of bone. In this study, polymer sponge replication method was used to fabricate porous hydroxyapatite scaffolds. Pure phase of hydroxyapatite scaffolds and the chemical bonding were verified via Fourier Transform Infrared and X-ray diffraction. Emission scanning electron microscopy (F E S E M) examination showed that the proposed scaffold has high interconnected pores that were achieved just after sintering at temperatures 1350 ºC for 2 hours. The percentage porosity values were estimated to …

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Deposition Of Ceo2/Tcp Thin Film On Stainless Steel 316 L By Rf Sputtering, Hiba A. Abdullah, Ahmed M. Al-Ghaban, Rana A. Anaee Jul 2026

Deposition Of Ceo2/Tcp Thin Film On Stainless Steel 316 L By Rf Sputtering, Hiba A. Abdullah, Ahmed M. Al-Ghaban, Rana A. Anaee

Engineering and Technology Journal

RF sputtering method was used for deposition 70wt% CeO2/TCP thin film on stainless steel 316L surface. The selection of ceria and tricalcium phosphate is according to the fact the importance of these materials in biomedical media. The produced coating was characterized by XRD, FESEM/EDS and AFM analysis, the result revealed that the obtained peaks from XRD refer to the deposited materials. When substitution of Ce was done, distorting of the lattice structure can occur suggesting certain incorporation of the cerium oxide within TCP lattice. Also, from SEM investigation uniformly homogeneous surface as a layer of (CeO2 + CaO) and TCP …

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Effect Of Zro2 And Y2o3 Deposition On Biological Behavior Of Ti-Base Alloys, Zainab Z. Al-Asadia, Fatimah J. Al-Hasani Jul 2026

Effect Of Zro2 And Y2o3 Deposition On Biological Behavior Of Ti-Base Alloys, Zainab Z. Al-Asadia, Fatimah J. Al-Hasani

Engineering and Technology Journal

Titanium has a good ability to attach to bone and living tissue, making it a perfect material for orthopedic implants. Because of the combination of high resistance to corrosion, biocompatibility and excellent mechanical properties. This work aims to study the Modifications of various base titanium implant samples producing by using powder technology (Ti-pure, Ti-45 % Ni, Ti10 % Co, and Ti-30 % Ta) by deposition of Nano Zirconia and yttria powders (70 %ZRO2 and 30% Y2O3 ). Chemical pretreatment carried out to prepare the implant surface before deposition, while the deposition process accomplished by pack cementation. The Characterizations of samples …

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Phase Transformations, Microstructure And Shape Memory Effect Of Nitiag Alloy With Different Atomic Percentages (At. % Ag) Manufactured By Casting Method, Saja M. Hussein, Khansaa D. Salman, Ahmed A. Hussein Jul 2026

Phase Transformations, Microstructure And Shape Memory Effect Of Nitiag Alloy With Different Atomic Percentages (At. % Ag) Manufactured By Casting Method, Saja M. Hussein, Khansaa D. Salman, Ahmed A. Hussein

Engineering and Technology Journal

In this paper, shape memory alloys (SMAs) (NiTi-based) have been manufactured by casting with a different atomic percentage of a silver element (0, 1, 2 and 3 at. % Ag) using a Vacuum Arc Remelting (VAR) furnace. The silver element is added to the binary alloys due to its excellent properties such as (anti-corrosion, anti-bacterial and high electrical conductivity), which make these alloys using in wider applications. These alloys with different atomic percentages (Ni55Ti45Ag0, Ni55Ti44Ag1, Ni55Ti43Ag2 and Ni55Ti42Ag3) have been manufactured. The successful manufacturing process has been achieved and proved via examinations and tests. The FESEM microscopic examinations show that …

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Assessment Of The Water Quality Index Of The Tigris River Between The University Of Baghdad And Diyala River, Ayat N. Abed, Gahyda Y. Al Kindi, Tariq A. Hussain Jul 2026

Assessment Of The Water Quality Index Of The Tigris River Between The University Of Baghdad And Diyala River, Ayat N. Abed, Gahyda Y. Al Kindi, Tariq A. Hussain

Engineering and Technology Journal

The Tigris River is considered as one of the two major rivers in Iraq. Many factories are located on both bank of the river such as the public company for soft drinks, Al-Dura oil refinery, chemical, plastic, and leather factories, Dura electricity station, and others. It is well known that most discharge effluents into the river do not match national standard specifications. In addition, the major aim of the presented work is to assess the Water Quality Index (WQI) for the Tigris River starting from The University of Baghdad to 0.5 km downflow the confluence of the Diyala River. The …

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Al2o3-Tio2-Pmma Bio-Composite Coating Via Electrostatic Spray Technique, Rasha A. Issa, Mohanad N. Al-Shroofy, Hanna A. Al-Kaisy Jul 2026

Al2o3-Tio2-Pmma Bio-Composite Coating Via Electrostatic Spray Technique, Rasha A. Issa, Mohanad N. Al-Shroofy, Hanna A. Al-Kaisy

Engineering and Technology Journal

This work aims preparation of polymer-based biocomposite coating by electrostatic spray method onto 316L stainless steel substrate, the present work will compare the effects of incorporation of Al2O3 and TiO2 particles at a different percentage of (10,15 and 20 % wt. from Al2O3 and TiO2 with (90,85 and 80% wt. PMMA - based electrostatic deposition coating is studied. The structure and chemical composition of composite coatings were studied by using (SEM) & (EDS) and mechanical properties (Microhardness and adhesion strength) of Al2O3-TiO2-PMMA composite coating. The SEM&EDX result showed that the composite coating to be dense with uniform dispersants and continuous …

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Estimation Of The Components Of Residential Solid Waste In Baqubah City And Their Generation Rate, Esraa Q. Shehab, Zainab B. Mohammed, Mohammed Y. Fattah Jul 2026

Estimation Of The Components Of Residential Solid Waste In Baqubah City And Their Generation Rate, Esraa Q. Shehab, Zainab B. Mohammed, Mohammed Y. Fattah

Engineering and Technology Journal

Municipal solid waste is of variable, non-uniform inconsistent nature and the method by which the sample to acquire is decisive if the results are to be reliable. For data collection, an integrated methodological approach was introduced, including field investigation, questionnaire survey, and personal interviews, which were employed to estimate the rate of waste production and physical composition at the source of generation. Samples were collected from different socio-economic clusters (socio-income level). According to the results of the preliminary survey for 99% confidence interval and 10% standard error, the optimum sample size was 105 households, in Baqubah City in Diyala Governorate …

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Chemical Precipitation Method For Sulphate Removal From Treated Wastewater Of Al-Doura Refinery, Aumar Alnakeeb, Rana Mohammed Rasheed Jul 2026

Chemical Precipitation Method For Sulphate Removal From Treated Wastewater Of Al-Doura Refinery, Aumar Alnakeeb, Rana Mohammed Rasheed

Engineering and Technology Journal

Wastewater treatment by Wastewater Treatment Plant, named (INGECO) in Doura refinery suffers from the elevated level of sulphate ion concentrations compared to the recommended EPA [14] specified (250 mg/L). The annual rate, maximum and peak sulphate concentrations that found to be 360; 425 and 550 mg/L respectively. In this study samples prepared from industrial wastewater and the average, maximum and peak sulphate concentrations to be used in chemical precipitation process by using BaCl2 or Al(OH)3. Results obtained from BaCl2 treatment refer to the optimum (dosage, mixing time and mixing speed) to be used in sulphate removal for reuse purpose were …

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Intelligent Controller Design Based On Wind-Solar System, Areeg F. Hussein, Hanan A. R. Akkar Jul 2026

Intelligent Controller Design Based On Wind-Solar System, Areeg F. Hussein, Hanan A. R. Akkar

Engineering and Technology Journal

This paper presents an Intelligent controller designed to mastery the output power flow from the Solar System, the Wind system, the sum of the two systems or from the battery system, according to the Maximum power point tracking algorithm, to ensure the continuity of the output power at fast time response. The proposed controller has been designed using MATLAB m-file and trained with the different number of hidden neurons using two different algorithms to get as fast a response time with minimum Mean Square Error (MSE) as possible which resulted in six hidden neurons using Levenberg-Marquardt training algorithms.

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Detection Of Confusion Behavior Using A Facial Expression Based On Different Classification Algorithms, Fatima I. Yasser, Bassam H. Abd, Saad M. Abbas Jul 2026

Detection Of Confusion Behavior Using A Facial Expression Based On Different Classification Algorithms, Fatima I. Yasser, Bassam H. Abd, Saad M. Abbas

Engineering and Technology Journal

Confusion detection systems (CDSs) that need Noninvasive, mobile, and cost-effective methods use facial expressions as a technique to detect confusion. In previous works, the technology that the system used represents a major gap between this proposed CDS and other systems. This CDS depends on the Facial Action Coding System (FACS) that is used to extract facial features. The FACS shows the motion of the facial muscles represented by Action Units (AUs); the movement is represented with one facial muscle or more. Seven AUs are used as possible markers for detecting confusion that has been implemented in the form of a …

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A Study Of The Effect Of Starch Content On The Water Absorption Of Pva/Starch Blends, Bushra H. Musa, Nahida J. Hameed Jul 2026

A Study Of The Effect Of Starch Content On The Water Absorption Of Pva/Starch Blends, Bushra H. Musa, Nahida J. Hameed

Engineering and Technology Journal

The present work aims to study physical tests such as the water absorption tests of PVA; PVA/corn starch blends at different mass percent (25, 30, 35, 40, and 50%) of corn starch after immersion in distilled water for ten minutes. The blends were also characterized by FTIR analysis, and an optical microscope. Casting method used to prepare samples. The results of water absorption exhibited that the weight losses of the sample increases the starch content rises in the PVA matrix. Also, it was found the highest value of the swelling ratio % at (50% PVA /50% Starch) blend, while minimum …

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The Effect Of The Number Of Key-Frames On The Facial Emotion Recognition Accuracy, Suhaila N. Mohammed, Alia K. Abdul Hassan Jul 2026

The Effect Of The Number Of Key-Frames On The Facial Emotion Recognition Accuracy, Suhaila N. Mohammed, Alia K. Abdul Hassan

Engineering and Technology Journal

Key-frame selection plays an important role in facial expression recognition systems. It helps in selecting the most representative frames that capture the different poses of the face. The effect of the number of selected keyframes has been studied in this paper to find its impact on the final accuracy of the emotion recognition system. Dynamic and static information is employed to select the most effective key-frames of the facial video with a short response time. Firstly, the absolute difference between the successive frames is used to reduce the number of frames and select the candidate ones which then contribute to …

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Determination Efficient Classification Algorithm For Credit Card Owners: Comparative Study, Raghad A. Azeez Jul 2026

Determination Efficient Classification Algorithm For Credit Card Owners: Comparative Study, Raghad A. Azeez

Engineering and Technology Journal

Today in the business world, significant loss can happen when the borrowers ignore paying their loans. Convenient credit-risk management represents a necessity for lending institutions. In most times, some persons prefer to late their monthly payments, otherwise, they may face difficulties in the loan payment process to the financial institution. Mainly, most fiscal organizations are considered managed and refined client classification systems, scanning a valid client from invalid ones. This paper produces the data mining idea, specifically the classification technique of data mining and builds a system of data mining process structure. The credit scoring problem will be applied using …

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Treatment Of Iraqi Municipal Wastewater By Up-Flow Anaerobic Sludge Blanket Reactor Uasb, Khairi R. Kalash, Majid A. Dixon, Hussein Ir. Sultan, Raad A. Ali Jul 2026

Treatment Of Iraqi Municipal Wastewater By Up-Flow Anaerobic Sludge Blanket Reactor Uasb, Khairi R. Kalash, Majid A. Dixon, Hussein Ir. Sultan, Raad A. Ali

Engineering and Technology Journal

In this work, the Upflow Anaerobic Sludge Blanket “UASB” reactor treated effluent wastewater to investigate the process performance on a pilot plant scale. Municipal wastewater at high and medium strength with different organic load rate OLR (0.6-9) kg COD m-3day-1 with the flow of 20 l/h, up-flow velocity 0.4 m/h, hydraulic retention time HRT 9 h at a temperature of (20-30 ºC) was evaluated. The wastewater concentration, including TSS, COD was measured, and the removal efficiencies of chemical oxygen demand (COD) and total suspended solid TSS were calculated and summarized as 45-85% and 70-75%, respectively, depending on organic load rate …

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Effect Of Pulse Electric Field On Water Characteristics As A Disinfection Function In Filtration Unit, Ghassan Abukhanafer, Alaa H. Al-Fatlawi, Hassan H. Joni Jul 2026

Effect Of Pulse Electric Field On Water Characteristics As A Disinfection Function In Filtration Unit, Ghassan Abukhanafer, Alaa H. Al-Fatlawi, Hassan H. Joni

Engineering and Technology Journal

This paper studied the impact of the addition of pulse electric-filed low voltage (PEF-LV) in the filtration process by designing, constructing, and operating a pilot-scale. The Disinfectant process (DP) demonstrated several benefits in terms of efficiency and ease of application, without the use of any chemical additive. This system contains two pairs of silver mesh electrodes inside the filtration column test with a low pulse voltage for killing microorganisms. The parametric effects of DP performance, such as alternating current pulse frequency and the voltage applied were investigated. The effect of PEF-LV on the biological, physical, and chemical characteristic of water …

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A Review On Microbial Fuel Cells, Baidaa A. Kitafa, Afaf J. Obaid Al-Saned Jul 2026

A Review On Microbial Fuel Cells, Baidaa A. Kitafa, Afaf J. Obaid Al-Saned

Engineering and Technology Journal

The Microbial Fuel Cell (MFC) is a bioreactor with which the chemical energy in chemical bonds of organic compounds are converted to electricity under anaerobic conditions through catalytic reactions of micro-organisms. It has been familiar for a long time that electricity can be generated directly through using bacteria to break organic matter. A microbial fuel cell can also serve in different wastewater treatment to destroy organic matter. The development of MFC technology requires a greater understanding of the microbial processes for MFCs, and their components, limitations, factors and design this system, to be simpler and large scale system developed; so …

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Investigating Nanoparticle Capture By Condensed Phase Coacervates And Their Mixtures, Sanjna A. Bhakta Jul 2026

Investigating Nanoparticle Capture By Condensed Phase Coacervates And Their Mixtures, Sanjna A. Bhakta

Chemical and Biological Engineering ETDs

The thermoresponsive polymers elastin-like polypeptides (ELPs) and poly(N-isopropylacrylamide) (PNIPAM) have served as a programmable bioseparation tool for applications in nanoparticle capture due to biocompatibility and tunable properties. This work investigates how the polymer composition of ELP and PNIPAM coacervates influences their phase behavior, structural morphology, and nanoparticle recruitment. In addition, the influence of interfacial interactions in nanoparticle recruitment using Tween 80 as a mechanistic probe was also investigated. Different mixtures of ELPs E1.40, E1.80, and E3 with PNIPAM14 and PNIPAM20 were used to characterize their phase behavior and analyze structural morphology using turbidity measurements and microscopy, respectively. Nanobead recruitment using …

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Tinyml-Based Embedded Vision System For Ic Detection In Microcontroller Manufacturing, Mark M. Pallones, King Harold A. Recto, Rynne Daven A. Barrios Jul 2026

Tinyml-Based Embedded Vision System For Ic Detection In Microcontroller Manufacturing, Mark M. Pallones, King Harold A. Recto, Rynne Daven A. Barrios

Electronics, Computer, and Communications Engineering Faculty Publications

Mixing of microcontroller unit (MCU) integrated circuits (ICs) during the final testing stage of semiconductor manufacturing can lead to material waste, production delays, and customer dissatisfaction. This issue often occurs when standard JEDEC Matrix Trays (JMTs) are reused without confirming that all ICs have been removed after testing, a process typically performed through manual inspection and therefore susceptible to human error due to high test volumes, small IC package sizes, and visual similarity between IC packages and tray surfaces. This study develops an automated IC Detection Test System using embedded vision to determine whether JMT trays are empty prior to …

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Mapping And Modeling Threat-Evoked Brain States After Early Life Adversity, Taylor W. Uselman Jul 2026

Mapping And Modeling Threat-Evoked Brain States After Early Life Adversity, Taylor W. Uselman

Biomedical Sciences ETDs

Early life adversity (ELA) increases lifelong neuropsychiatric vulnerability. Yet how ELA reorganizes brain-wide activity and circuit coordination across later experience remains unclear. This dissertation tests the hypothesis that ELA alters adult brain-wide activity and responses to threat through disrupted coordination among neural systems that regulate emotional experience, including prefrontal-limbic and monoaminergic systems. Longitudinal manganese-enhanced MRI of adult mice exposed to standard or fragmented early care, combined with computational processing and statistical modeling, quantified brain states before, during, and long after innate predator threat. These studies established that acute threat evokes large-scale, distributed brain activity that evolves over time. ELA potentiates …

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Multiscale Network Modeling Of Native And Modified Photosynthetic Light-Harvesting Complexes, Zane E. Armijo Jul 2026

Multiscale Network Modeling Of Native And Modified Photosynthetic Light-Harvesting Complexes, Zane E. Armijo

Chemical and Biological Engineering ETDs

Photosynthetic light-harvesting complexes harvest solar energy and direct electronic excitations toward reaction centers with exceptional efficiency. This dissertation models the Fenna--Matthews--Olson complex of green sulfur bacteria, coupled to the PscA1 reaction center, as a chromophoric network. Forster resonance energy transfer theory, validated against numerically exact hierarchical equations of motion, was implemented in kinetic Monte Carlo simulations to resolve fine-grained excitation-transport pathways. The predicted charge-transfer efficiency of 77\% agrees with experiment, with the FMO2 monomer and its gateway pigment governing interfacial transfer. Systematic single, multi, and symmetry-preserving site removals, interpreted through Mobius inversion, identify critical pigments and show that cooperative effects …

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Impact Of Gas Interactions With Nano Porous Geological Material In The Presence Of Water Vapor, Matthew D. Powell Jul 2026

Impact Of Gas Interactions With Nano Porous Geological Material In The Presence Of Water Vapor, Matthew D. Powell

Chemical and Biological Engineering ETDs

Predicting gas transport in nanoporous geological material requires understanding competitive adsorption and transport under humid conditions. However, most adsorption studies rely on single-component equilibrium measurements that do not capture these effects. This dissertation develops an experimental methodology to directly quantify multicomponent gas adsorption and breakthrough behavior under controlled relative humidity. The method was first applied to the Kr/Xe–N2–H2O system, where it resolved competitive adsorption behavior in humid porous media and produced a bivariate model relating noble gas adsorption to noble gas partial pressure and water saturation. The methodology was then extended to the CO2–N2 H2O system. Results showed that water …

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Mechanisms Of Advanced And Energy Efficient Wastewater Treatment Technologies, Derek Belka Jul 2026

Mechanisms Of Advanced And Energy Efficient Wastewater Treatment Technologies, Derek Belka

Civil Engineering ETDs

This dissertation combines meta-omics, microbial ecology, and hydrodynamic analysis to explore mechanisms of enhanced biological phosphorus removal (EBPR) and aerobic granular sludge (AGS) in municipal wastewater treatment. Metagenomic and functional gene profiling of a laboratory sequencing batch reactor fed with amino acids and proteins, and with a low abundance of known polyphosphate-accumulating organisms (PAOs), revealed abundant Herpetosiphonaceae and Dermatophilaceae families possessed key PAO metabolic traits, including phosphate scavenging, anaerobic carbon pathways, and ppk2 gene variants aligned with established PAOs. These findings suggest amino acid-driven EBPR can occur via previously unrecognized taxa, challenging current engineering assumptions and highlighting the need for …

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