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Investigation Of Fine-Grain Cu And Cu Alloys For Low-Temperature Hybrid Bonding Applications, Sarabjot Singh Jan 2026

Investigation Of Fine-Grain Cu And Cu Alloys For Low-Temperature Hybrid Bonding Applications, Sarabjot Singh

Electronic Theses & Dissertations (2024 - present)

Hybrid bonding has emerged as a key enabler for next-generation three-dimensional (3D) integration, offering fine-pitch interconnects and improved electrical performance. However, conventional Cu–Cu hybrid bonding typically requires elevated temperatures to achieve sufficient diffusion and interface quality, posing challenges for temperature-sensitive device integration and process compatibility. This work investigates materials engineering approaches to enable low-temperature Cu–Cu bonding through both microstructure design and alloying strategies.

This work begins by examining grain refinement in Cu as a pathway to enhance diffusion through increased grain boundary density, providing efficient atomic transport without introducing additional elements. Three Cu-based systems Cu–Co, Cu–Ag, and Cu–Al were systematically …


Photo And Spatial Control Of Rna Structures And Functions: Exploring Positional Effects And Photo-Responsiveness Of Azobenzene Modified Nucleotides, Jinxi Du Jan 2026

Photo And Spatial Control Of Rna Structures And Functions: Exploring Positional Effects And Photo-Responsiveness Of Azobenzene Modified Nucleotides, Jinxi Du

Electronic Theses & Dissertations (2024 - present)

RNA molecules perform many important biological functions by forming complex three-dimensional structures stabilized by base pairing, tertiary interactions, and metal ion coordination. Because RNA function depends strongly on its structure, methods that allow reversible control of RNA conformation and activity are important for understanding RNA behavior and for potential therapeutic applications. However, achieving reversible and site-specific control of RNA structure, especially at the single-nucleotide level, remains challenging. In this dissertation, I developed and applied azobenzene-modified nucleotides as a chemical tool to enable optical and spatial control of RNA structure and function.

The first part of this dissertation focuses on establishing …


The Chemistry Of Red Lipstick: The Impact Red Lipstick Has On Society, Lilliana Weldeslassie Jan 2026

The Chemistry Of Red Lipstick: The Impact Red Lipstick Has On Society, Lilliana Weldeslassie

Electronic Theses & Dissertations (2024 - present)

Cosmetic chemistry is deeply embedded in everyday life, shaping the products people use from morning to night. Among these, red lipstick stands out as a formulation that blends complex chemistry with a cultural meaning. This thesis examines the scientific foundations of red lipstick through its chemical composition, pigment structure, toxicological history, analytical methods, and evolving sustainability practices. Historically, red lipsticks relied on high-risk ingredients such as lead, mercury, and other toxic metals, reflecting an era before chemical safety and regulatory oversight were incorporated.21 Modern formulations have established safer synthetic dyes, natural waxes, plant-based oils, and stabilizers created to optimize …


Developments And Applications Of Transport Of Intensity Equation Imaging And Optical Diffraction Tomography In Bioimaging, Shane D. Carney Jan 2026

Developments And Applications Of Transport Of Intensity Equation Imaging And Optical Diffraction Tomography In Bioimaging, Shane D. Carney

Electronic Theses & Dissertations (2024 - present)

Non-invasive imaging schemes are highly sought after methodologies in biology and metrology, where maintaining the physical state of a sample is important. Quantitative phase imaging (QPI) techniques non-invasively reconstruct the relative phase delay imparted onto an optical field due to transmission through a sample. Phase delay is proportional to the thickness and refractive index of the sample, but is lost in the intensity measurement process. Digital holographic microscopy (DHM) and transport of intensity equation (TIE) phase imaging are two high-resolution QPI techniques. DHM is a well-researched, accurate, and widely implemented technique, but can be difficult to implement in labs without …


Climate And Environmental Controls On Forest Soil Organic Matter Cycling, Genevieve Goebel Jan 2026

Climate And Environmental Controls On Forest Soil Organic Matter Cycling, Genevieve Goebel

Dartmouth College Ph.D Dissertations

Climate change factors act on the soil environment in complex ways, known to disturb soil organic carbon (C). Rising global temperatures and alterations to regional precipitation and nitrogen deposition regimes may contribute to the intensification of global change by accelerating the rate of biological decomposition and CO2 efflux to the atmosphere. The magnitude and endurance of the disturbance to soil organic C across landscapes and throughout time that climate change factors may pose to soil C cycling are not comprehensively understood. These knowledge gaps in our field make it challenging to anticipate how soil environments and the vast ecosystems that …


Implementation Of A 3-Dimensional Hydrodynamic Numerical Model On A Large Northern Lake, Kirin Lorente Jan 2026

Implementation Of A 3-Dimensional Hydrodynamic Numerical Model On A Large Northern Lake, Kirin Lorente

Theses and Dissertations (Comprehensive)

Climate change is impacting high latitude regions disproportionately more than those at a lower latitude. With polar lakes being highly sensitive to changes in the climate, shifts in lake ice dynamics and hydrodynamics are indicators of such changes in regional and global climates. These changes impact future seasons in a positive feedback loop, where changes in winter ice cover impact open water nutrients levels and lake thermal structure. This highlights the importance for long-term monitoring. Despite the abundance of lakes distributed across Northern Canada, there has been limited research conducted on these sentinels of climate change.

Specifically, Great Bear Lake …


Assessing Dissolved Organic Matter Sources And Dynamics In Urban Stormwater: Implications For Greenhouse Gases, Harper W. Schmalz Jan 2026

Assessing Dissolved Organic Matter Sources And Dynamics In Urban Stormwater: Implications For Greenhouse Gases, Harper W. Schmalz

Theses and Dissertations (Comprehensive)

Stormwater management ponds (SWMPs) are important aspects of land-use planning and increasingly recognized as active sites of biogeochemical processing that influence carbon cycling; however, little research has investigated the controls on dissolved organic and dissolved inorganic carbon (DOC and DIC) within these systems. This thesis examined the processing and transformations of dissolved carbon between three compartments to support the development of a greenhouse gas (GHG) box-model for urban stormwater ponds, including SWMP sediment, surface water, and vegetation. The objective of this thesis was to assess the biogeochemical processes that govern the rate and transformation of DOC and DIC between these …


Non-Gaussian Phenomena In Light Scattering And Applications, Shubham Atul Dawda Jan 2026

Non-Gaussian Phenomena In Light Scattering And Applications, Shubham Atul Dawda

Graduate Studies Theses and Dissertations 2026

Physical reality is rarely deterministic; which, when probed by electromagnetic fields that also fluctuate, leads to observables that are most efficiently modelled as statistical processes. At equilibrium, this is usually achieved by invoking the Gaussian statistics of underlying physical processes, however, in practice, one often encounters out-of-equilibrium conditions where Gaussian descriptions may not suffice. Such situations are plentiful in nature– from biology to astronomy. This dissertation addresses several non-Gaussian phenomena associated with light scattering, and includes specific models’ derivations, experimental techniques developments, and demonstrations of potential applications. The systematic presentation will consider circumstances that infringe upon specific assumptions of the …


Integrated Optical Probes For Confocal Scanning Imaging And Adjustable Coherent-Gated Dynamic Sensing, Yonglin Huang Jan 2026

Integrated Optical Probes For Confocal Scanning Imaging And Adjustable Coherent-Gated Dynamic Sensing, Yonglin Huang

Graduate Studies Theses and Dissertations 2026

Optics and photonics have been one of the most important sciences and technologies that impact modern human life in a big way. For example, fiber-optics for communications and artificial intelligence. Optical probes are critical components for optical imaging and optical sensing technologies that have been actively researched and developed in the past decades. Advanced fiber-optic sensor probes with smaller size, better performance, lower noise, higher photon efficiency, rapid sensing time, and lower cost are needed in many applications, such as nanoscale material science, chemistry, and biomedical fields, etc.  In this project, new fiber-optic sensor probe technologies and integrated micro-optic devices …


2024 Annual Operations And Maintenance Report 2024 Bres Annual Summary Report For Work Completed In Quadrant 4, Butte-Silver Bow Department Of Reclamation And Environmental Services Jan 2026

2024 Annual Operations And Maintenance Report 2024 Bres Annual Summary Report For Work Completed In Quadrant 4, Butte-Silver Bow Department Of Reclamation And Environmental Services

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


Comparative Assessments Of Methane Flux Measurement Techniques In Serpentinite-Influenced Groundwater Wells, Madison J. Stetson Jan 2026

Comparative Assessments Of Methane Flux Measurement Techniques In Serpentinite-Influenced Groundwater Wells, Madison J. Stetson

Open Access Master's Theses

Methane (CH4) emissions from continental serpentinizing systems represent a significant component of Earth’s carbon cycling. Despite increasing recognition of serpentinite-hosted water-rock interactions as a source of trace gases, standardized field methodologies for quantifying trace gas flux from groundwater wells and similar subsurface conduits remain limited. This study addresses that gap by evaluating the reliability and replicability of three chamber-based sampling methods for measuring gas flux in serpentinite-hosted groundwater systems accessed by groundwater monitoring wells. Field measurements were conducted at the Coast Range Ophiolite Microbial Observatory (CROMO) within the McLaughlin Natural Reserve in Lower Lake, California, a site …


Seasonal Variations In Co2 Emission From Poultry Manure-Amended Soils In Two Contrasting Tropical Agroecosystems, Gladys M. Akande, Adebayo J. Adeyemo, Chidozie J. Oraegbunam, Iduh J.J. Otene, Ezekiel C. Are, Babatunde S. Ewulo, Chioma M. Ahukaemere, Samuel O. Kolawole, Sunday E. Obalum Jan 2026

Seasonal Variations In Co2 Emission From Poultry Manure-Amended Soils In Two Contrasting Tropical Agroecosystems, Gladys M. Akande, Adebayo J. Adeyemo, Chidozie J. Oraegbunam, Iduh J.J. Otene, Ezekiel C. Are, Babatunde S. Ewulo, Chioma M. Ahukaemere, Samuel O. Kolawole, Sunday E. Obalum

Applied Environmental Research

The soil remains the largest carbon sink, the capacity of which varies spatiotemporally and with anthropogenic activities, with implications for carbon dioxide (CO2) emissions and associated global warming. Despite the increasing popularity of organic amendments in the ecologically and anthropoculturally diverse farming systems of tropical Africa, manure-induced CO2 emissions in this region with high soil-carbon-sequestration potential are poorly documented. This study assessed seasonal CO2 emissions from poultry manure-amended sandy-clay-loam and sandy-loam soils in the Rainforest-Savannah and Southern Guinea Savannah zones, respectively, of Nigeria. Following manure application at 3 rates (0, 10, and 15 t ha-1), soil samples were collected during …


Activated Carbon Prepared From Residual Eucalyptus Wood For The Removal Of Methyl Orange: Equilibrium, Kinetics, Thermodynamics, And Desorption, Mathin Jaikua, Phuthidhorn Thanaphu, Sunisa Ungwiwatkul, Jakkrawut Maitip, Kanyarak Prasertboonyai Jan 2026

Activated Carbon Prepared From Residual Eucalyptus Wood For The Removal Of Methyl Orange: Equilibrium, Kinetics, Thermodynamics, And Desorption, Mathin Jaikua, Phuthidhorn Thanaphu, Sunisa Ungwiwatkul, Jakkrawut Maitip, Kanyarak Prasertboonyai

Applied Environmental Research

This research utilizes activated carbon derived from residual Eucalyptus wood (EW) for the removal of methyl orange (MO). The residual Eucalyptus wood-based activated carbon (EWAC) was produced through carbonization at 400 °C (EWC) followed by activation with a mass ratio of H3PO4 to EWC of 1:3, which was conducted at 800 °C for 1 h. The characterization of the EWAC involved various analytical techniques, including FTIR, XRD, BET, and CHN analysis. The adsorption parameters, such as pH (range: 3–8), adsorbent dose (range: 0.01–0.5 g per 50 mL of MO solution), contact time (range: 5–720 min), initial MO concentration (range: 5–600 …


Blue Carbon Stock Assessment And Climate Resilience Potential Of Mangrove Forest In Hung Thang Commune, Vietnam, Hla Phong Ko, Pham Hong Tinh, Nguyen Thuy Duong Jan 2026

Blue Carbon Stock Assessment And Climate Resilience Potential Of Mangrove Forest In Hung Thang Commune, Vietnam, Hla Phong Ko, Pham Hong Tinh, Nguyen Thuy Duong

Applied Environmental Research

Mangrove forests are vital blue carbon sinks that contribute to climate change mitigation and coastal resilience. This study assessed the carbon stock and spatial‒temporal dynamics of a mangrove forest in Hung Thang commune, Hai Phong Province, Vietnam, via a combination of field measurements, soil organic carbon (SOC) analysis, and normalized difference vegetation index (NDVI)-based remote sensing models. The results revealed that mangroves in the Hung Thang community store an average of 87.42 tC ha-1, with SOC accounting for approximately 19% of the total carbon. A generalized additive model (GAM) analysis revealed a consistent increase in carbon stocks between 1996 and …


Bioremediation Potential Of Indigenous Stutzerimonas Stutzeri 08tbb Isolated From Mercury-Contaminated Gold Mining Sites In Indonesia, Uun Rohmawati, Juanita Hibatullah, Achmad Rodiansyah, Yunita Messe, Dwi Nur Aini Fajriah Jan 2026

Bioremediation Potential Of Indigenous Stutzerimonas Stutzeri 08tbb Isolated From Mercury-Contaminated Gold Mining Sites In Indonesia, Uun Rohmawati, Juanita Hibatullah, Achmad Rodiansyah, Yunita Messe, Dwi Nur Aini Fajriah

Applied Environmental Research

Artisanal and small-scale gold mining (ASGM) widely uses mercury (Hg) in the amalgamation process, and the resulting waste is often discharged directly into the environment, posing serious risks to ecosystems and human health because of the high toxicity of Hg. This study aimed to isolate and screen indigenous Hg-tolerant bacteria from contaminated gold mining sites in Indonesia; characterize the most effective isolate using morphological, biochemical, and molecular approaches; evaluate Hg(II) degradation performance using ICP‒OES, FTIR, and SEM analyses; and identify key metabolites involved in Hg detoxification through untargeted LC–HRMS metabolomics. A total of 51 bacterial isolates were obtained from Hg-contaminated …


Ammonium Adsorption From Aqueous Solutions Using Mnfe2o4-Functionalized Coffee Husk Biochar Nanocomposites : An Evaluation Of Hno3 And Naoh Activation, Thuy-Tien Do, Huu-Tap Van, Thi-Minh-Thu Nguyen Jan 2026

Ammonium Adsorption From Aqueous Solutions Using Mnfe2o4-Functionalized Coffee Husk Biochar Nanocomposites : An Evaluation Of Hno3 And Naoh Activation, Thuy-Tien Do, Huu-Tap Van, Thi-Minh-Thu Nguyen

Applied Environmental Research

This research investigated the development of MnFe2O4-based composite adsorbents (MFO@CFA and MFO@CFB) by activating coffee husk-derived biochar with HNO3 and NaOH, followed by synthesis through coprecipitation and hydrothermal techniques. The structural and chemical properties of the nanocomposites were characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. Batch adsorption experiments were used to assess ammonium removal efficiency across a range of conditions: solution pH (3–8), contact time (5–120 min), adsorbent dosage (0.2–3 g L-1), and initial ammonium concentration (10–60 mg L-1). The findings indicated that compared with MFO@CFB, which was synthesized from NaOH-activated biochar, MFO@ CFA, derived …


Assessing Forest Fragmentation And Edge Expansion In Nan Province, Thailand, Using Landsat Data (2014–2022), Kasidit Rison, Marut Fuangarworn, Chatchawan Chaisuekul Jan 2026

Assessing Forest Fragmentation And Edge Expansion In Nan Province, Thailand, Using Landsat Data (2014–2022), Kasidit Rison, Marut Fuangarworn, Chatchawan Chaisuekul

Applied Environmental Research

The increasing pressure from land-use change and agricultural expansion in Nan Province, northern Thailand, has accelerated forest fragmentation and reduced the ecosystem service value (ESV) of the landscape. This study aims to: assess land use and forest fragmentation change in Nan Province between 2014 and 2022, and evaluate the impact of land use change on ESV. Landsat 8 OLI satellite imagery from 2014 and 2022 was used to classify land cover into five types: forest, agriculture, settlements, exposed soil, and others. Forest fragmentation was evaluated using landscape metrics such as patch number, mean patch size, edge length, and core area. …


Performance And Mechanisms Of Activated Natural Coagulants For Efficient Microcystis Removal Via Coagulation–Flocculation In Thailand, Apiradee Sukmilin, Peangtawan Phonmat, Ratcha Chaichana Jan 2026

Performance And Mechanisms Of Activated Natural Coagulants For Efficient Microcystis Removal Via Coagulation–Flocculation In Thailand, Apiradee Sukmilin, Peangtawan Phonmat, Ratcha Chaichana

Applied Environmental Research

Thailand produces fruit peels and seeds rich in natural polymers, which can serve as eco-friendly coagulants to control algal blooms. In this study, banana peel (Musa spp.), orange peel (Citrus sinensis), basil seed (Ocimum basilicum) mucilage, and chia seed (Salvia hispanica) mucilage were used. These activated natural coagulants with aluminum were compared with nonactivated and commercial coagulants (ferric sulfate, ferrous sulfate, and polyaluminum chloride) for Microcystis removal. Phytochemical composition analysis, Fourier transform infrared (FTIR) spectroscopy, and oxidation–reduction potential (ORP) analysis were conducted. The results revealed that banana and orange peels contain phenolic compounds, …


Evaluating Sediment Control Strategies Using Swat Based Bmp Assessment In A Tropical Highland Watershed, Northern Thailand, ฺBanchongsak Faksomboon, Wilailak Suanmali Jan 2026

Evaluating Sediment Control Strategies Using Swat Based Bmp Assessment In A Tropical Highland Watershed, Northern Thailand, ฺBanchongsak Faksomboon, Wilailak Suanmali

Applied Environmental Research

Soil erosion remains a critical environmental challenge in the tropical highland watersheds of Southeast Asia, where steep terrain, intense monsoonal rainfall, and intensive land use interact to accelerate sediment generation and downstream degradation. This study aims to quantify spatial patterns of sediment yield and to systematically evaluate the effectiveness of individual and combined best management practices (BMPs) at both the watershed and subwatershed (SWW) scales using the Soil and Water Assessment Tool (SWAT) in a tropical highland watershed in northern Thailand. Baseline simulations reveal pronounced spatial heterogeneity in erosion severity, with substantial portions of the watershed exhibiting moderate to extreme …


Application Of Diatom Indices To Monitor Environmental Shifts In The Downstream Tuntang River, Central Java, Mirza Hanif Al Falah, Tri Retnaningsih Soeprobowati, Hadiyanto -, Muhammad Isnaini Ibnu Sabil, Marta Wojewódka-Przybył, Łukasz Kruszewski, Paweł Rydelek Jan 2026

Application Of Diatom Indices To Monitor Environmental Shifts In The Downstream Tuntang River, Central Java, Mirza Hanif Al Falah, Tri Retnaningsih Soeprobowati, Hadiyanto -, Muhammad Isnaini Ibnu Sabil, Marta Wojewódka-Przybył, Łukasz Kruszewski, Paweł Rydelek

Applied Environmental Research

Diatoms are widely recognized as sensitive bioindicators for reconstructing past water quality and ecological changes in aquatic ecosystems. In this study, multiple diatom-based indices were applied to sediment cores collected from three downstream stations of the Tuntang River, Central Java, to infer long-term environmental change in a tropical river system. A total of 38 sediment subsamples were analyzed, with dominant taxa including Fragilaria crotonensis (2.4–18.6%), Nitzschia palea (3.1–22.4%), and Aulacoseira granulata (2.0–15.8%), indicating sustained nutrient enrichment. Diatom indices consistently classified conditions as mesotrophic to eutrophic throughout the sediment profiles. The occurrence of the marine diatom Cylindrotheca closterium (up to 6.3%) …


Sustainable Approach For The Removal Of Cu(Ii) From Aqueous Solutions Using Lotus Seedpod-Alginate Composite Biosorbents, Lan Tran-Nguyen, Hue Tran Nguyen-Le, Hong T Hi Anh Nguyen, Tran Nguyen-Phuong-Dung, Ly Kim-Phung, Huynh Quoc-Khanh, Nguyen Minh-Nhut, Phuong Lan Tran-Nguyen Jan 2026

Sustainable Approach For The Removal Of Cu(Ii) From Aqueous Solutions Using Lotus Seedpod-Alginate Composite Biosorbents, Lan Tran-Nguyen, Hue Tran Nguyen-Le, Hong T Hi Anh Nguyen, Tran Nguyen-Phuong-Dung, Ly Kim-Phung, Huynh Quoc-Khanh, Nguyen Minh-Nhut, Phuong Lan Tran-Nguyen

Applied Environmental Research

Turning waste or agricultural byproducts into valuable products has recently become a concern of scientists. In this study, the facile and cost-effective synthesis of a biocomposite derived from lotus seedpod (LS) and alginate (AG) was further applied for Cu2+ ion uptake from aqueous solutions. SEM images revealed the layered structures of the composites, which were thin and irregularly stacked sheets of a complex 3D network. The abundant functional groups on the surface of the LS-based material and its negative zeta potential value of -37.50 mV also facilitated efficient Cu2+ removal. Adsorption results revealed a Cu2+ adsorption efficiency (AE) and experimental …


Tree Composition And Carbon Sequestration Potential Of A University Campus In Bangkok, Thailand, Chaiwat Boonpeng, Pawanrat Butrid Butrid, Marisa Pischom, Satatip Noikrad Jan 2026

Tree Composition And Carbon Sequestration Potential Of A University Campus In Bangkok, Thailand, Chaiwat Boonpeng, Pawanrat Butrid Butrid, Marisa Pischom, Satatip Noikrad

Applied Environmental Research

Trees play important roles in atmospheric carbon dioxide (CO2) absorption and climate change mitigation. The objective of this study was to assess tree characteristics and carbon sequestration potential at Ramkhamhaeng University (Hua Mak Campus), Bangkok, Thailand. Tree attributes, including species composition, abundance, diameter at breast height (DBH), and tree height, were recorded. Tree biomass, carbon storage, and CO2 sequestration were estimated using appropriate allometric equations. A total of 2,149 trees were recorded in the study area, corresponding to a tree density of 45.8 trees ha-1. The tree community was dominated by the palm family (Arecaceae), while Terminalia ivorensis was the …


Initial Screening Of Halophilic Plastic-Degrading Bacteria From Mangrove Water And Sediment In Pekalongan, Indonesia, Novia Safinatunnajah, Muhammad Zainuri, Aris Ismanto, Tony Hadibarata, Kunarso -, Sugeng Widada, Hermin Pancasakti Kusumaningrum, Candra Wahyuningsih Jan 2026

Initial Screening Of Halophilic Plastic-Degrading Bacteria From Mangrove Water And Sediment In Pekalongan, Indonesia, Novia Safinatunnajah, Muhammad Zainuri, Aris Ismanto, Tony Hadibarata, Kunarso -, Sugeng Widada, Hermin Pancasakti Kusumaningrum, Candra Wahyuningsih

Applied Environmental Research

Microplastic pollution in tropical mangrove ecosystems represents an increasing environmental concern, particularly in coastal regions such as Pekalongan, Indonesia, where industrial and residential activities contribute substantially to plastic waste. This study aimed to isolate and preliminarily screen halophilic bacteria from mangrove sediments and seawater collected from a plastic-impacted coastal area. Using mineral salt medium (MSM) supplemented with polyethylene glycol (PEG), six bacterial strains were obtained and evaluated for their potential to interact with polyethylene (PE) and polypropylene (PP) on the basis of gravimetric weight loss measurements. Among the isolates, Halomonas Cupida A1, Marinobacter nauticus A6.3, and Marinobacter nauticus SD5.2 exhibited …


Effects Of The Psb-To-Ow Ratio And Light Intensity On Biogas Composition During Phototrophic-Assisted Anaerobic Fermentation Of Organic Waste, Kridsana Jirasansawat, Sirilak Prasertkulsak, Nitiwist Teangthai Jan 2026

Effects Of The Psb-To-Ow Ratio And Light Intensity On Biogas Composition During Phototrophic-Assisted Anaerobic Fermentation Of Organic Waste, Kridsana Jirasansawat, Sirilak Prasertkulsak, Nitiwist Teangthai

Applied Environmental Research

The integration of phototrophic processes into anaerobic fermentation offers a promising strategy for improving biogas quality; however, the combined effects of the photosynthetic bacteria-to-organic waste (PSB-to-OW) ratio and light intensity remain unclear. In this study, the photosynthetic bacteria (PSB)-assisted anaerobic fermentation of municipal organic waste under varying PSB-to-OW ratios and light intensities was evaluated. An optimal PSB-to-OW ratio of 1:2 resulted in significantly higher CH4 concentrations and lower CO2 and H2S concentrations than the other tested ratios did (p < 0.05). At this ratio, moderate illumination (2000 lx) resulted in the highest CH4 concentration (68.2 ± 0.3%), compared with 1000 lx (61.5 ± 0.4%) and 4000 lx (63.1 ± 0.5%). Under illumination, the CO2 and H2S concentrations were lower than those under dark conditions, indicating a more favorable biogas composition. Kinetic analysis indicated that CO2 and H2S exhibited apparent first-order behavior under illumination, with the highest rates occurring at 2000 lx (kH2S = 0.093 day-1; kCO2 = 0.059 day-1), suggesting light-dependent transformation processes. Metagenomic analysis revealed a microbial community dominated by sulfide-oxidizing (Chlorobium sp.), photoheterotrophic (Rhodopseudomonas sp.), and syntrophic bacteria, supporting coupled carbon conversion and sulfur transformation. Overall, optimization of the …


Amino Acid Isotope Dynamics And Associated Ecological Metrics Across Accretionary Tissues Of Marine Fishes, Sofia Piccone Jan 2026

Amino Acid Isotope Dynamics And Associated Ecological Metrics Across Accretionary Tissues Of Marine Fishes, Sofia Piccone

Open Access Master's Theses

Compound-specific isotope analysis of amino acids (CSIA-AA) applied to the organic growth layers of accretionary fish tissues, including eye lenses, otoliths, and scales, has made it possible to reconstruct histories of fish physiology, ecology, and environmental conditions. Yet it remains uncertain whether amino acid isotope values, and the ecological information they contain, are conserved across these archival tissues or if differences in tissue composition, growth, protein structure, and metabolic routing produce tissue-specific offsets that alter inferred carbon sources, d15NBaseline, and trophic position. We tested this question with individually paired CSIA-AA of eye lenses, otoliths, and scales …


Metal–Organic Frameworks : Opportunities And Challenges In Nutrient Recovery, Suchana Amnuaychaichana, Chi-Wang Li, Pongsak (Lek) Noophan, Sumeth Wongkiew Jan 2026

Metal–Organic Frameworks : Opportunities And Challenges In Nutrient Recovery, Suchana Amnuaychaichana, Chi-Wang Li, Pongsak (Lek) Noophan, Sumeth Wongkiew

Applied Environmental Research

Nutrient recovery from waste streams is a critical strategy for promoting sustainable agriculture and mitigating environmental degradation. Essential nutrients commonly present in organic waste and wastewater, such as nitrogen and phosphorus, can be reclaimed and reintegrated into agricultural systems. Metal‒organic frameworks (MOFs), which are composed of metal clusters coordinated with organic ligands, have emerged as promising materials for adsorption and have the potential for nutrient recovery and pollutant removal because of their high porosity, large surface area, and tunable physicochemical properties. These attributes enable MOFs to serve in diverse applications, including heavy metal adsorption, organic pollutant degradation, and nutrient transformations. …


Healing Our Life Source: Riparian Eco-Cultural Restoration In Blue Lake Rancheria At School Creek, A Tributary Of Baduwa't In Northern California, Rae Mcgrath, Lily Moore, Keneti Jesus Pinones, Colin Rogers, Aberdeen Spade Jan 2026

Healing Our Life Source: Riparian Eco-Cultural Restoration In Blue Lake Rancheria At School Creek, A Tributary Of Baduwa't In Northern California, Rae Mcgrath, Lily Moore, Keneti Jesus Pinones, Colin Rogers, Aberdeen Spade

Environmental Science & Management Senior Capstones

School Creek, a tributary in the Baduwa’t (mad river) Watershed, is a riparian corridor that is key habitat for Coho Salmon. This project is under the management of the Blue Lake Rancheria, located on the ancestral home of the Wiyot people, and was conducted by cal poly humboldt students. The restoration of School Creek is an ongoing project aimed at repairing the health of the riparian corridor, improving the creek’s channel structure, and creating a diverse community of culturally significant plant species. Previous restoration efforts have established plantings to further develop the riparian habitat and are surveyed within this report. …


Removal And Monitoring Of Ammophila Arenaria In A Previously Restored Foredune Site In Humboldt Coastal Nature Center, Lucas Benjamin Griffin, Haylee Lynn Kimball, Maya Contreras, Ava Christenson Jan 2026

Removal And Monitoring Of Ammophila Arenaria In A Previously Restored Foredune Site In Humboldt Coastal Nature Center, Lucas Benjamin Griffin, Haylee Lynn Kimball, Maya Contreras, Ava Christenson

Environmental Science & Management Senior Capstones

Coastal dunes are important ecosystems that provide vital habitat for rare and endangered species as well as vital ecosystem services. However, since the late nineteenth century, coastal dune ecosystems have been invaded and altered by Ammophila arenaria, which is a beach grass species native to Europe. The dunes within the Humboldt Coastal Nature Center are one such example of this. This property is currently managed by the non-profit organization Friends of the Dunes, which has been working to restore the dunes' ecology and topography. Our project focuses on the monitoring and maintenance of a 2021 restoration project within a 17,794 …


Woody Ryno Farms Native Prairie Plant Restoration & Invasive Management Conservation Management Report, Jezebel Kenny, Rowan Haeger, Ian Mendonca, Annika Weihl Jan 2026

Woody Ryno Farms Native Prairie Plant Restoration & Invasive Management Conservation Management Report, Jezebel Kenny, Rowan Haeger, Ian Mendonca, Annika Weihl

Environmental Science & Management Senior Capstones

Coastal prairies are biodiverse and sensitive landscapes that support a variety of grassland species in mediterranean climates. Hedgerows may act as a natural barrier for coastal prairies or agricultural regions, aiding in natural protection and support for biodiversity. Humboldt County, California, hosts a number of agricultural regions, including Woody Ryno Farms, a small-scale agricultural operation, on the edge of Dows Prairie near the coast of Mckinleyville. This project aims to continue restoration activity being conducted on the site, helping to increase native biodiversity and agricultural productivity. Project objectives include conducting a plant assessment, applying treatments to individual plants where necessary, …


Data-Driven Methodologies For Mapping Cultural Heritage: The Case Of The National Coal Heritage Area, West Virginia, Usa, Hossain Mohammad Nahyan Jan 2026

Data-Driven Methodologies For Mapping Cultural Heritage: The Case Of The National Coal Heritage Area, West Virginia, Usa, Hossain Mohammad Nahyan

Graduate Theses, Dissertations, and Problem Reports (ETD)

The objective of this dissertation was to develop a comprehensive, data-driven spatial framework for characterizing the complex cultural landscape of the National Coal Heritage Area (NCHA) in West Virginia. By transitioning away from traditional, heuristic spatial mapping, this research integrates advanced spatial statistics, machine learning, and GIS-based methodologies to objectively quantify the physical, visual, and cultural dimensions of the post-mining environment. The research is structured around three interconnected empirical studies, each addressing a specific scale of the Landscape Character Assessment (LCA) framework to support heritage conservation and sustainable spatial planning. The first paper focused on landform classification, developing an automated …