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Spatiotemporal Dynamics Of Mountain Front Recharge Flow Paths And Their Contribution To Alluvial Aquifer Water Supply, Mikaela Bollag-Miller

Graduate Student Theses, Dissertations, & Professional Papers

Mountain Front Recharge (MFR) is a critical recharge source for alluvial basin aquifers throughout the Intermountain West, yet the spatial and temporal dynamics of distinct recharge pathways remain poorly constrained. This study investigates the seasonal and spatial dynamics of MFR pathways and evaluates their impact on the Missoula Aquifer, a sole-source alluvial aquifer in western Montana, USA. MFR includes both surface-water inflows from mountain areas and Mountain Block Recharge (MBR), the groundwater contribution to the basin aquifer. A valley-scale water balance was employed to estimate first-order contributions and temporal fluctuations of MBR flow paths. A three-layer steady-state MODFLOW groundwater model …

Stakeholder Co-Design Of Sustainable Urban Pest Management Strategies, Elizabeth C. Lowe, Nathan J. Butterworth, Alexander Austin, Cameron Webb, Tanya Latty

Research outputs 2022 to 2026

The high levels of broad-spectrum insecticides used to manage invertebrates in many cities around the world has significant environmental and health impacts. Integrated pest management (IPM) is a framework for sustainable pest control practice, but uptake of IPM remains low in most cities. We used participatory action research with pest management industry stakeholders (practitioners, industry representatives, researchers and government employees) to identify key issues in urban pest management in Australia, set priorities for change and discuss collaborative solutions. Via an online survey and a face-to-face workshop, the participants identified the key themes of education and training, public awareness, environmental impacts …

Inside Out: Improving Large Model Safety, Wei Zhao

Dissertations and Theses Collection (Open Access)

While Large Language Models (LLMs) and Multimodal Large Language Models (MLLMs) are at the frontier of current advancements in artificial intelligence, demonstrating remarkable capabilities across diverse applications, there are growing concerns about their reliability and security. LLMs remain vulnerable to adversarial attacks through carefully crafted prompts that circumvent safety mechanisms, while MLLMs face additional security challenges stemming from their multimodal nature. Despite considerable efforts in reinforcement learning from human feedback (RLHF) and supervised fine-tuning, existing safeguards have proven inadequate in addressing these critical vulnerabilities. This inadequacy stems from the fact that these models are inherently blackboxes that do not provide …

Sparse Gradient Training For Recommender Systems, Yunke Qu, Liang Qu, Tong Chen, Xiangyu Zhao, Jianxin Li, Hongzhi Yin

Research outputs 2022 to 2026

Recommender systems are widely applied in numerous online platforms such as shopping and social media platforms. They typically utilize large embedding tables that map users and items to dense vectors of uniform sizes. As the number of users and items continues to grow, this design leads to significant memory consumption and computational inefficiencies. This challenge is particularly pronounced in scenarios such as federated learning, where model parameters are updated locally on edge devices with limited computational resources before being transmitted to a central server for aggregation. Numerous approaches have been proposed to address this issue, among which embedding pruning methods …

Beyond Words: A Systematic Multimodal Framework For Text, Images, And Extreme Helpfulness In Online Reviews, Alvaro J. Aguado Marin

Dissertations

Online product reviews have become increasingly multimodal, combining text with media-rich elements such as images. However, academic research has largely examined textual features in isolation, overlooking how visual content and its interaction with text shape perceived helpfulness. This dissertation addresses that gap by developing and empirically validating a comprehensive framework capturing how textual, visual, and contextual features collectively influence review evaluation. Grounded in the Elaboration Likelihood Model (ELM) and extended through the Text-Image Elaboration Likelihood Model (TI-ELM), the framework advances understanding of how consumers process content from both user- and business-generated sources. It also lays the foundation for examining emerging …

Computational Design Of Nanoporous Materials For The Adsorption Of Per- And Polyfluoroalkyl Substances, Daniel D. Mottern

Dissertations

Per- and polyfluoroalkyl substances (PFAS) are a large family of chemicals that have seen wide usage due to their fluorinated carbon backbone. The presence of strong C-F bonds in the backbone lends PFAS molecules high thermal and chemical stability, as well as strong hydrophobicity and lipophobicity. This combination of properties has led to heavy use of PFAS as surfactants, non-stick coatings, and aqueous foam forming films and flame retardants. However, these properties bring their own consequences. The high chemical and thermal stability of PFAS renders them persistent, with the C-F bonds resisting naturally occurring forms of degradation. Existing forms of …

Patterns Of Llm Weaponization: A Comparative Analysis Of Exploitation Incidents Across Commercial Ai Systems, George Antoniou

Faculty and Staff Publications & Presentations

This comparative study examines patterns of Large Language Model (LLM) weaponization through systematic analysis of four major exploitation incidents spanning from 2023-2025. While existing research focuses on isolated incidents or theoretical vulnerabilities, this study provides one of the first comprehensive comparative frameworks analyzing exploitation patterns across state-sponsored cyber-espionage (Anthropic Claude incident), academic security research (GPT- 4 autonomous privilege escalation), social engineering platforms (SpearBot phishing framework), and underground criminal commoditization (WormGPT/FraudGPT ecosystem). Through comparative analysis across eight dimensions: Adversary sophistication, target selection, exploitation techniques, autonomy levels, detection evasion, attribution challenges, defensive gaps, and capability democratization, this research identifies critical cross-case patterns …

Empowering Youth In A Changing Climate: Design, Implementation, And Evaluation Of A Salt Marsh Summer Science Program, Dan Levesque

Graduate Masters Theses

Climate change presents not only environmental challenges but also emotional challenges for today’s youth. This thesis documents the design, implementation, and evaluation of a field-based summer science program aimed at empowering adolescents with coastal salt marsh ecology while addressing climate change emotions and science identity development. The program, based in a Massachusetts salt marsh, was adapted from existing public environmental curricula and guided by place- and experience-based learning principles. Over Spring and Summer 2025, 13 students (ages 13-18) participated in extra-curricular field trips, hands-on research activities, and reflective discussions about the environment and the emotions it brings forth. Pre- and …

From Enhancement To Substitution: A Strategic Provocation On Simulation-Based Sport, Grant B. Morgan, Andreas Stamatis

Journal of Applied Sport Management

Advances in artificial intelligence, large-scale machine learning, and simulation technologies are rapidly transforming how sport is played, analyzed, and consumed. To date, most scholarly and industry discussions frame these technologies as tools that enhance embodied sport by improving performance, officiating, media production, and fan engagement. This paper extends that conversation by posing a more provocative strategic question: under what conditions might simulation move from enhancement to substitution? Focusing explicitly on sport as a business and entertainment enterprise, we argue that many of sport’s core sources of cultural and economic value—uncertainty of outcome, narrative continuity, legitimacy, and collective meaning—are structurally …

Role-Playing Game Studies: A Transmedia Approach Por José Pablo Zagal, Y Sebastian Deterding, (Editores). (2018). [Reseña], Cristo Leon, Edgar Meritano

Journal of Roleplaying Studies and STEAM

"Role-Playing Game Studies: A Transmedia Approach," editado por José P. Zagal y Sebastian Deterding (2018b), es una recopilación exhaustiva del estado actual de la investigación sobre los juegos de rol a través de diversas disciplinas, culturas y medios. El libro traza la historia de los juegos de rol desde sus precursores en los juegos de guerra (wargames) hasta los juegos de mesa (Tabletop), el juego de rol en vivo (live-action role-play), y los juegos de rol contemporáneos de computadora y en línea. Cada capítulo ofrece perspectivas y hallazgos de disciplinas clave como …

Journal Of Roleplaying Studies And Steam (Jrpssteam) Vol. 4 [2025], Número 2 (Issue 2), Cristo Leon, Romano Ponce-Díaz Phd, Ivan Avila Gonzalez Phd, James Lipuma Dr., Bruce G. Bukiet, Ricardo Victoria-Uribe, Nazario Robles-Bastida, Chris Birmingham, Ximena Diaz Santillan, Edgar Francisco Vázquez Martínez He, Jorge Prieto Terrones, Juan Carlos C. González Vidal S, Edgar Meritano, Laura Magela Garcés Ramírez

Journal of Roleplaying Studies and STEAM

En una sesión de juego por medio del registro lingüístico se organiza la escena, se orienta la manera de nombrar las tareas, se distribuyen los roles actanciales, se establecen la expectativas; por lo tanto, se establece una puesta en escena. De tal forma, las prácticas lúdicas y ficcionales se configuran a partir de nuestra mirada del mundo e irremediablemente también reconfiguran esa misma mirada. El ser y el estar en un espacio es la especificidad mediática fundamental de los juegos de rol; dicho de otra manera, en los sistemas de juego de rol dentro de sus universos narrativos, en su …

Electrochemical Characterization And Modulation Of Biological Processes, Yue-Qi Li, Wei-Hua Huang, De-Chen Jiang, Bao-Hong Liu, Bin Su, Yang Tian, Jing-Juan Xu, Ping Yu, Feng Zhao, Huang-Xian Ju, Jing-Hong Li

Journal of Electrochemistry

Electrochemical processes lie at the core of biological function, governing energy transduction, metabolic flux, and molecular signaling. Recent advances in electrochemical science now allow these processes to be probed and controlled with unprecedented spatial, temporal, and chemical resolution. In this review, we present an integrated framework that progresses from fundamental mechanisms to analytical technologies and functional modulation. We begin by outlining electron transfer pathways in mitochondrial respiration, microbial extracellular electron transfer, and DNA- and protein-based charge conduction, followed by the principles of photon-electron conversion in photosynthesis and the central role of redox equilibrium in coordinating cellular responses. We then highlight …

Review Of Video Steganography By Using Deep Learning Methods: Datasets, Techniques, And Evaluations, Noor Fahem Sahib, Soukaena Hassan Hashem, Ekhlas Falih Naser

Journal of Soft Computing and Computer Applications

The growing prevalence of cyber threats, including fraud and attacks, has intensified the demand for secure methods of safeguarding confidential information exchanged between users. As telecommunications increasingly rely on multimedia data, video steganography has become a prominent technique to address these concerns. By embedding sensitive data within video files, this approach enhances protection against unauthorized access and common internet-based attacks, offering a robust layer of security in an era of escalating digital risks. With the introduction of Deep Learning (DL) steganography methods recently, video steganography can be defined as a rapidly developing subject within information security. This study provides a …

Hate Speech Detection Using Optimized Feature Representation Via Spiral-Grey Wolf Optimizer-Based Machine Learning Approaches, Noor S. Farhan, Matheel E. Abdulmunim, Hasanen S. Abdullah

Journal of Soft Computing and Computer Applications

Hate speech detection is crucial as social media diversifies. This research present a lightweight, scalable system using traditional machine learning methods along with a new approach called Spiral-Grey Wolf Optimizer (S-GWO).

S-GWO effectively selects key features that consider both meaning and content from the Term Frequency Inverse Document Frequency (TF-IDF) space, leading to high-quality representation without excessive computing power.

The propoused system was tested on Arabic and another English datasets using six machine learning methods: SVM, RF, LR, KNN, NB, and SGD. It achieved 92% accuracy and F1 score on the Arabic dataset, while reaching 100% accuracy on the English …

(R2164) The Nature Of The Big Bang Singularity In Inhomogeneous Szekeres Cosmological Frameworks, Ahmed M. Al-Haysah, Abdul-Majeed Al-Izeri

Applications and Applied Mathematics: An International Journal (AAM)

Without killing vector fields, the Szekeres metric is an explicit example of an anisotropic and inhomogeneous solution to the Einstein equations. The inhomogeneous Szekeres cosmological models (ISCM) within the Big Bang singularity (BBS) are obtained. This indicates that the Szekeres solution represents a more general class of exact solutions. It is known to exhibit axial symmetry. We investigate a Big Bang theory of the cosmos, which unexpectedly predicts that the universe started at the so-called BBS a finite length of time ago. A growing number of astrophysical researchers are using inhomogeneous extensions of the Friedmann-Lemaitre-Robertson-Walker (FLRW) solution and, by extension, …

Novel Spectrophotometric Method For The Determination Of Paclitaxel Through Complex Formation With Osmium, Basima A.A.Saleem, Salim A. Mohammed, Amer Th. Al-Taee

Turkish Journal of Chemistry

Paclitaxel (Pac) is an important anticancer bioactive compound, and the availability of an accurate and robust analytical method for its quantification is of utmost importance. In this investigation, a novel, direct, and reliable spectrophotometric method has been proposed for the estimation of Pac via a complex formation reaction with osmium (Os). The method was based on the reaction of Pac with Os tetroxide, which produced a yellowish-brown complex. The resulting complex is soluble in water and displays a maximum absorption peak at 482 nm. The reaction conditions, including reactant concentration, pH, temperature, and reaction time, were optimized to obtain the …

Synthesis, Characterization, Antimicrobial, Antioxidant, And Antiinflammatory Evaluation And Molecular Docking Studies Of N-((2-Hydroxy-3-(2-(Substitutedbenzylidene)Hydrazine-1-Carbonyl)Naphthalen-1-Yl)(3-Nitrophenyl/3,4-Dimethoxyphenyl)Methyl)Acetamide Derivatives, Shikha Kamboj, Alka Yadav, Samridhi Thakral, Rekha Tanwar, Sunil Kumar, Vikramjeet Singh

Turkish Journal of Chemistry

Hydrazone chemistry has become important and plays a key role in the development of organic compounds. Hydrazones can be useful pharmacophores for creating novel derivatives, owing to their broad range of activities. In this study, a series of N-((2-hydroxy-3-(2-(substitutedbenzylidene)hydrazine-1-carbonyl)naphthalen-1-yl)(3-nitro-phenyl/3,4-dimethoxyphenyl)methyl)acetamide derivatives were prepared, characterized by FTIR, 1H-NMR, 13C-NMR, and mass spectroscopy, and evaluated for their antimicrobial, antiinflammatory, and antioxidant activities along with in silico studies. The substituted derivatives were synthesized by the reaction of acetonitrile, chlorosulphonic acid, and substituted benzaldehyde with the hydrazones. The antimicrobial evaluation showed that compound 3i had more antimicrobial potential than the other tested molecules. Compound 3j …

Enhancing Analytical Performance Of Tyrosinase-Based Sensors With Nanoparticles For Detection Of Isoproterenol, Aysel Oktay, Sevi̇nç Kurbanoğlu, Gülsüm Gündoğdu, Cem Bülent Üstündağ, Frieder W. Scheller, Aysu Yarman

Turkish Journal of Chemistry

In this work, electrochemical biosensors utilizing tyrosinase (Tyr) for the detection of the nonselective beta-adrenergic agonist isoproterenol (ISO) are presented. Three different configurations for immobilizing Tyr on a graphite electrode (GE) are compared: (1) GE modified with poly(diallyldimethylammonium chloride) (PDADMAC), PDADMAC/Tyr/GE; (2) PDADMAC combined with iridium nanoparticles (IrNPs) in a stepwise preparation, resulting in PDADMAC/IrNPs/Tyr/GE; and (3) a composite of PDADMAC and IrNPs mixed with Tyr at a 1:1 (v:v), forming PDADMAC/(IrNPs-Tyr)/GE. Surface morphology was characterized using scanning electron microscopy (SEM). Cyclic voltammetry (CV) and amperometry were applied to characterize the biosensor’s performance. Within the linear range of 5 μM …

Synthesis Of Biogenic Silver Nanoparticles From Apricot Kernel Extracts For The Colorimetric Determination Of Gold, Ayça Gi̇rgi̇n, Hi̇lal Akbiyik, Buse Tuğba Zaman, Omid Nejati, Ayça Bal Öztürk, Gülten Çeti̇n, Sezgi̇n Bakirdere

Turkish Journal of Chemistry

Gold is abundant in nature, however, precise and reliable analytical methods for its detection are required stemming from its increasing prevalence in environmental, biological, and industrial systems, as well as the growing interest in understanding its function in living organisms and its effects on human health. This study investigates the use of biogenically synthesized silver nanoparticles (AgNPs) for the preconcentration and determination of gold ions prior to determination by UV-Vis spectrophotometry. AgNPs were synthesized by reducing silver nitrate through the use of an apricot kernel extract as both reducer and stabilizer agent. The colloidal yellowish AgNPs interacted with gold ions, …

Efficient Recovery Of Y3+ From Aqueous Media Using Mdlm Technique:Transport Behavior And Kinetic Modeling, Volkan Demi̇rel, Ramazan Donat, Hacer Şensöz

Turkish Journal of Chemistry

This study investigates the extraction behavior of Y³⁺ ions using a Multi-Dropped Liquid Membrane (MDLM) system that employs di(2-ethylhexyl) phosphoric acid (D₂EHPA) as the carrier ligand. The focus is on the system’s ability to transport ions between aqueous phases selectively. The extracted complex was analyzed spectrophotometrically via ultraviolet–visible (UV–Vis) measurements after complexation with 0.05% Arsenazo III. The aim of this study was to determine the influence of the optimum D₂EHPA carrier concentration, together with the pH and temperature conditions of the donor and acceptor phases, on the system’s extraction performance. Accordingly, a series of extraction experiments was performed at different …

Bioorganometallic Tagging Of N-Acetylhistamine With An Fe(Co)₃ Unit: Synthesis, X-Ray Structure, And Protonation Behavior, Salah Merniz, Louiza Himed, Rofia Djerri, Belkis Akachat

Turkish Journal of Chemistry

This study highlights the potential of organometallic carbonyl complexes as selective markers for biomolecules, enabling sensitive infrared (IR) detection. The regio- and stereoselective coupling of N-acetylhistamine, a histidine analogue, with the precursor complex 1 [Fe(CO)₃(1,4-η⁵-N-pyridiniocyclohexa-1,3-diene)] BF₄ affords the labeled complex 3 [Fe(CO)₃(1,4-η⁵-N-acetylhistaminocyclohexa-1,3-diene)]. X-ray diffraction (XRD) confirms the exo stereochemistry and reveals a rigid, well-defined architecture. IR and 1H nuclear magnetic resonance spectroscopic studies combined with IR-monitored acid–base titration demonstrate the complex’s stability in aqueous media between pH 5 and 8, alongside a modest increase in basicity relative to the free ligand. These findings establish the Fe(CO)₃ moiety as a robust …

A Method For Advance Detection Of Underground Concealed Water Hazards In Coal Mines Based On Borehole Transient Electromagnetic Method And Vector Synthesis, Fan Tao, Hao Yue, Li Ping, Zhao Rui, Liu Zaibin, Ma Liang, Li Peng, Yan Junsheng

Coal Geology & Exploration

Background The advance detection of underground concealed water hazards in coal mines is crucial to ensuring the safe and efficient roadway tunneling. The borehole transient electromagnetic (TEM) method allows for long-distance advance detection. However, due to the limitation of the spatial structure of boreholes, currently available techniques can only effectively identify low-resistivity anomalies (e.g., water-bearing structures) in the radial direction, leaving blind areas in the primary tunneling direction (i.e., the axial direction of boreholes). Objective and Method To address this challenge, this study proposed a method for the advance detection of concealed water hazards in the axial direction of boreholes …

Investigating Surface-Borehole Transient Electromagnetic Responses From Veined Orebodies Considering Induced Polarization Effects, Li Jianhui, Wang Yao, Wang Wenchuang, Xie Shaojian, Zhu Siwei

Coal Geology & Exploration

Objective The observational data derived using the surface-borehole transient electromagnetic (TEM) method tend to feature complex curve morphologies, a problem posing significant challenges to data processing and interpretation. This study aims to ascertain the mechanisms behind the generation of such complex responses using forward modeling.Methods Using the vector finite element-based spectral method and the Cole-Cole model, this study developed a 3D forward modeling technique incorporating the induced polarization (IP) effect. By constructing a typical theoretical model of low-resistivity veined orebodies, it systematically analyzed the electromotive force (EMF) responses excited by transmitter loops at different orientations. Results and Conclusions The …

Performance And Migration Path Tracing Of Magnetic Grouts For Fractured Rock Masses, Shang Hongbo, Wang Hao, Wang Xiaodong, Qiao Wei, Wang Tiantian, Sun Junqing, Sun Jie

Coal Geology & Exploration

Objective For coal mining areas in the middle reaches of the Yellow River basin, sealing mining-induced fractures via grouting serves as an effective approach to preventing water inrushes from coal seam roofs while also protecting groundwater resources. However, accurately identifying the migration paths of grouts remains a bottleneck for the further application of grouting modification technology to fractured rock masses. Methods This study investigated a coal mine threatened by both water inrushes from the coal seam roof and a short supply of water resources within the Jurassic coalfield in the middle reaches of the Yellow River basin, focusing on the …

Application Of Long-Distance Tunneling And Detection For Advance Detection In Excavation Using Shield Tunneling Machines, Chen Chao, Li Ping, Li Wei, Wei Rong

Coal Geology & Exploration

Objective and Method During the rapid excavation process using shield tunneling machines in coal mines, the advance detection of concealed geological anomalies encounters challenges of limited space and insufficient accuracy. To overcome these issues, this study investigated highly-located drainage roadway 3211 in the Tiandi Wangpo Coal Mine in Jincheng City, Shanxi Province using the long-distance tunneling and detection technology, the core of which is long directional boreholes combined with comprehensive borehole geophysical prospecting. This roadway is located in the roof of the No.3 coal seam, and it is necessary to conduct shield construction in the stable sandstone layer located from …

A Method For Interpretating Acoustic Reflection Imaging Logging Data Of Fractured-Vuggy Reservoirs Based On Their Theoretical Response Characteristics, Huang Ruokun, Jiang Kai, Wu Xingneng, Ma Kunyu, Su Yuanda, Wang Bing, Chen Xu

Coal Geology & Exploration

Objective During the exploration and development of fractured-vuggy carbonate reservoirs, acoustic reflection imaging logging technology enables the detection of fractured-vuggy bodies around wells. However, this technology suffers from unclear response characteristics and a strong multiplicity of solutions. Focusing on the Tarim Oilfield, this study aims to establish a tailored interpretation method by integrating geological and geophysical characteristics. The purpose is to enhance the identification accuracy and reliability of fractured-vuggy bodies in these reservoirs. Methods Based on the distribution characteristics of fractured-vuggy carbonate reservoirs in the Tarim Oilfield, this study established the numerical simulation models of three typical fractured-vuggy bodies: inter-breccia …

Co2-Water Displacement Characteristics Of Saturated Sandstones With Different Pore Structures, Liu Ting, Li Jinglin, Li Yi, Dan Wendong, Diao Yujie, Ma Xin

Coal Geology & Exploration

Objective The pore structures of clastics play a crucial role in assessing the potential of saline aquifers for geologic CO₂ sequestration. Current studies on pore structures during CO₂ sequestration focus primarily on artificial cores. However, compared to artificial cores, natural cores feature more complex pore size distributions and stronger heterogeneity. Methods This study examined a natural core from deep reservoirs in the Ordos Basin and two artificial cores with different porosities through CO₂-water displacement experiments under water-saturated conditions. Using a nuclear magnetic resonance (NMR) analysis and imaging system for multiphase fluid displacement, this study analyzed the …

Multi-Field Coupling-Based Numerical Simulations Of Co2 Storage In Saline Aquifers: A Case Study Of The Dingji Coal Mine, Huainan Mining Area, Li Dianshang, Zheng Sijian, Liao Qingfa, Miao Wei, Tian Yuchen, Zhang Helong, Liu Yanzhi, Liu Shiqi

Coal Geology & Exploration

Background Saline aquifers are characterized by extensive distribution, abundant reserves, and substantial potential for CO₂ storage, establishing them as the most promising geological media for carbon capture, utilization, and storage (CCUS). CO₂ storage in saline aquifers plays a crucial role in mitigating the greenhouse effect and achieving the goals of peak carbon dioxide emissions and carbon neutrality. Thoroughly investigating CO₂ storage in deep saline aquifers within the Huainan mining area helps alleviate the regional pressure of carbon emission reduction while also providing important support for expanding the technical pathways of CCUS and promoting its engineering applications. Methods …

Environmental Risk Assessment Of Co2 Storage Combined With The Overlying Coal Mining, Gu Leiyu, Li Wenhui, Huang Wei, Zhou Quanchao, Zhu Yalong, Li Xiaying, Liu Guizhen, Li Qi

Coal Geology & Exploration

Objective Carbon capture, utilization, and storage (CCUS) technology serves as a key method for carbon neutrality. However, large-scale engineering applications of CCUS are still confronted with serious challenges of environmental risks. Therefore, systematic environmental risk assessment plays an essential role in ensuring the environmental safety and social acceptability of CO₂ geological storage projects. Methods Targeting the CO₂ geological storage project combined with overlying coal mining in Zhengning County, Gansu Province, this study performed the environmental risk assessment of CO₂ leakage based on the requirements of the Technical Guideline on Environmental Risk Assessment for Carbon Dioxide Capture, Utilization, …

Physical Simulation Experiments On 4d Visualization Of Dynamic Methane Diffusion And Adsorption In Low-Porosity And Low-Permeability Coals, Liu Tong, Jiao Baizhuo, Lin Baiquan, Sang Shuxun, Yang Wei, Liu Shiqi, Liu Ting, Li He, Yang Mingxing

Coal Geology & Exploration

Objective and Method The diffusivity of methane (CH₄) in coal seams significantly influences the surface extraction of coalbed methane (CBM) and underground gas drainage. However, the visualized characterization of the diffusion and migration processes of CH₄ in coals remains challenging. To address this issue, this study systematically demonstrated the similarity between krypton (Kr) and CH₄ in their adsorption and diffusion behavior in coals. Utilizing Kr—a gas with high X-ray attenuation—as a tracer substitute for CH₄, this study achieved the transparent observation of the dynamic gas migration process in low-porosity, low-permeability, and heterogeneous coals using …