Physical Sciences and Mathematics Commons^™

Orphan Basalts: Understanding The Origins Of Unassigned Eastern Oregon Basalts, Angela Rae Stetson

Dissertations and Theses

For more than a century, scientists have studied the geologic stratigraphy of eastern Oregon, which chronicles a rich history of volcanic activity spanning millions of years. Recent and ongoing geologic mapping of the northeastern Harney Basin -- along a corridor east of Highway 395 between the towns of Burns and John Day -- provides a more detailed understanding of an area originally mapped only in reconnaissance during the 1960s. At that time, geologic units were poorly delineated, often with entire quadrangles mapped as a single unit. For example, over 90% of the Calamity Butte quadrangle was previously mapped as 'Tba' …

Multi-Wavelength Study Of 1erass J085039.9−421151 With Erosita, Nustar, And X-Shooter, A. Zainab, A. Avakyan, V. Doroshenko, P. Thalhammer, E. Sokolova-Lapa, R. Ballhausen, N. Zalot, J. Stierhof, S. Hämmerich, C. M. Diez, P. Weber, T. Dauser, K. Berger, P. Kretschmar, K. Pottschmidt, Pragati Pradhan, N. Islam, C. Maitra, J.B. Coley, P. Blay, R.H.D. Corbet, R.E. Rothschild, K. Wood, A. Santangelo, U. Heber, J. Wilms

Publications

The eROSITA instrument on board Spectrum-Roentgen-Gamma (SRG) has completed four scans of the X-ray sky, leading to the detection of almost one million X-ray sources in eRASS1 alone, including multiple new X-ray binary candidates. We report on analysis of the X-ray binary 1eRASS J085039.9−421151, using a ∼55 ks long NuSTAR observation, following its detection in each eROSITA scan. An analysis of the eROSITA and NuSTAR X-ray spectra in combination with X-shooter data of the optical counterpart provide evidence of an X-ray binary with a red supergiant (RSG) companion, confirming previous results. However, we did determine a cooler spectral type for …

Stable Coronal X-Ray Emission Over 20 Yr Of Xz Tau, Steven M. Silverberg, Hans Moritz Günther, Pragati Pradhan, David A. Principe, P.C. Schneider, Scott J. Wolk

Publications

XZ Tau AB is a frequently observed binary young stellar object in the Taurus Molecular Cloud; XZ Tau B has been classified as an EXOr object. We present new Chandra/HETG-ACIS-S observations of XZ Tau AB, complemented with variability monitoring of the system with XMM-Newton, to constrain the variability of this system and identify high-resolution line diagnostics to better understand the underlying mechanisms that produce the X-rays. We observe two flares with XMM-Newton but find that outside of these flares the coronal X-ray spectrum of XZ Tau AB is consistent over 20 yr of observations. We compare the ensemble of XZ …

Fourier Analyses Of Optical Profilometry As An Inferential Measurement For Impact Coverage., Langdon Feltner, Paul Mort

15th International Conference on Shot Peening

A critical consideration in peening process design is achieving sufficient impact coverage. Conventional methods for assessing coverage rely on manual inspection, which is time-consuming and poorly suited for automated control. In this work, we investigate the use of frequency-domain analysis to quantify surface modification in peened samples using optical profilometry (OP) data. Three-dimensional surface maps of Almen strips were acquired using a high-resolution OP system and analyzed via fast Fourier transform (FFT) to compute spatial power spectral densities (PSDs). PSD maps and radially averaged profiles reveal consistent amplification of harmonic components similar to the nominal particle size, with increasing intensity …

Reduced Order Approach For Peening Stress Field Variability, Langdon Feltner, Paul Mort

15th International Conference on Shot Peening

A common goal in shot peening research is to connect operational parameters to resultant residual stress fields, providing a means to control and optimize the effectiveness of surface treatment. In practice, experimental measurements of residual stresses are often averaged values over regions that are large in comparison to an impact dimple. In fact, the stochastic nature of impact locations leads to residual stress fields that are distributed. Finite element peening simulations confirm this observation. The goal of this report is to connect operational parameters to localized fluctuations in residual stress through probabilistic reasoning (Figure 1). In particular, the development of …

Synthesis And Characterization Of Fe-Zn Bimetallic Nanoparticles Via Two-Step Laser Ablation And Their Antibacterial Activity, Hudhaifa M. Mohammed, Sahar Naji Rashid

Karbala International Journal of Modern Science

In this study, Nd: YAG laser at a wavelength of (1064 nm), energies of (300 and 400 mJ), and a pulse repetition rate of (3 Hz) was used to synthesize metallic nanoparticles from iron and zinc individually using a one-step pulsed laser ablation approach, followed by the two-step synthesis of bimetallic nanoparticles. The physical properties of the synthesized nanoparticles were then investigated using UV-visible (UV-Vis), X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and energy-dispersive X-ray (EDX) techniques. The results of characterization of the obtained NPs confirmed the formation of core-shell nanocomposites, as evidenced by the increased absorbance intensity of …

Enrichment Factors And Play Fairway Mapping Of Helium In Typical Zones Of The Ordos Basin, Gao Jianrong, Tao Shizhen, Liu Xiangbai, Yang Wei, Zhao Zhenyu, Chen Xiuyan, Xu Wanglin, Zhang Chunlin, Song Wei, Chen Yue, Huang Junping, Ma Zhanrong

Coal Geology & Exploration

Background The Ordos Basin enjoys abundant natural gas resources, which generally bear helium, making this basin hold great helium resource potential. In this case, detailed exploration is essential for the future transition from natural gas-helium joint exploration to special helium exploration in the basin.Objective and Method To systematically investigate the distribution and potential of helium resources in the Ordos Basin, natural gas samples were taken from different areas of the basin for analysis and tests. To examine the primary factors controlling helium accumulation and enrichment, this study conducted a systematic analysis of the basement, sedimentary rock layers, fault systems, …

"From Global Stocktake To Global Delivery: A Policy Roadmap For Cop30 Implementation" How Can We Hold Stakeholders Accountable And Foster Global Collaboration?, Joshua Underhill

COP30

The Earth is facing a climate catastrophe. According to NASA (2024), the Earth's average surface temperature in 2024 was the warmest on record. The same article outlines that the Earth is about 1.47 degrees Celsius warmer than the preindustrial period1. A core mechanism designed to address this challenge, and other key concerns, is the Global Stocktake GST, which is a process within the Paris Agreement assessing collective progress towards key goals.

This policy paper will primarily focus on the history of the global stocktake, before delving into the future of the GST, the NDC, and global mutirao, all with the …

From Dialogue To Delivery: Engaging Non-State Actors In Gst Follow-Up, Aya Mohamed

COP30

Climate action is falling short where it matters most, on the ground, because those doing the work are often excluded from the system's tracking progress. The Global Stocktake (GST), meant to assess global climate efforts, remains focused on national governments, leaving out non-state actors (NSAs) who lead much of the real-world delivery. This exclusion stems from structural gaps in Nationally Determined Contributions (NDCs) and the lack of formal ways for NSAs to engage meaningfully. Existing tools, like voluntary platforms and consultations, are not enough, they lack enforcement and true integration. This paper proposes two practical solutions: AI-powered Nested Climate Accounting, …

Turning Ndc 3.0 Into Action: An Implementation Framework For Hard-To-Abate Sectors Decarbonization - The Brazil Case Study, Mohamed Khaled

COP30

Brazil stands to lead an industrial transition using green hydrogen for steel production, using its renewable energy advantage to bridge the gap between pilot project success and commercial implementation. Brazil's hydrogen project—including 12 planned hubs and Vale's strategic partnerships—shows how the country can implement its NDC 3.0 commitment s into actionable steps while establishing a replicable model for developing countries. Green hydrogen emerges as a transformative solution for steel decarbonization, offering an alternative way to replace the coal pathway. Hydrogen-based direct reduction fundamentally changes steelmaking by utilizing renewable-powered electrolysis to produce hydrogen that reduces iron ore without carbon byproduct s. …

Capacity Building And Action For Climate Empowerment (Ace): A Technical Review, Salman Almudawib

COP30

Capacity Building and Action for Climate Empowerment (ACE) is a core pillar for climate change mitigation through people’s participation, education, and empowerment (UNFCCC, n.d.; Action for Climate Empowerment, 2025). This article describes technological and digital resources that support ACE, particularly in the COP30 environment. It also identifies inventive methods and the stumbling blocks alongside the best digital instruments that facilitate local-level empowerment, targeting innovation centers, AI education, indigenous knowledge systems, and the integration of policies (IFLA, 2025; Mbuvha et al., 2024). One of the key anticipated outcomes is the Baku-to-Belém Roadmap, aimed at mobilizing $1.3 trillion annually for climate action …

Carbon Metabolism And Multidrug Resistance In Bacillus Mobilis And Cupriavidus Campinensis Isolated From Cadmium-Spiked Soils, Philips O. Akinwole, Emma E.C. Jacobs '25, Nina G. Shaffer '25

Biology Faculty publications

Heavy metal contamination and antibiotic resistance are critical environmental and public health challenges, often exacerbated by co-selection pressures in polluted environments. This study identifies and characterizes Bacillus mobilis and Cupriavidus campinensis, two cadmium-tolerant bacterial species isolated from cadmium-amended soils with cadmium (Cd²⁺) concentrations exceeding those typically found in highly contaminated soils. Both species exhibited multidrug resistance and the ability to metabolize specific carbon substrates, including pyruvic acid methyl ester, itaconic acid, D-galactonic acid-γ-lactone, Tween-40, and Tween-80. These substrates enhance microbial activity and heavy metal bioavailability, supporting their potential roles in bioremediation, especially through the targeted introduction of …

Process And Mechanism Of Defluorination Using Magnesium Chloride-Modified Coal Gangue, Zhao Li, Zhou Wangxu, Zhang Qing, Xing Mingfei, Xu Feng, Kong Weifang, Liu Yifei, Qin Guangyu

Coal Geology & Exploration

Background The rapid development of industry has resulted in a yearly increase in wastewater discharge, which induces a gradually rising fluorine concentration in water. In this context, removing fluoride using natural materials and industrial waste has emerged as a popular research topic. Coal gangue, one of the largest contributors to industrial waste in China, contains substantial clay minerals, and its pore structure can be effectively improved through modification. This helps significantly enhance its adsorption performance and thus achieve efficient fluoride removal from water. Methods This study investigated coal gangue from a typical mining area of the Henan Energy and Chemical …

A Modular Casing While Drilling Rig For Large-Diameter Horizontal Boreholes For Underground Rescue, Fan Dong, Ni Xiaoyang, Mu Shuyuan, Zou Zujie, Wen Guojun, Li Yingping, Lu Feifei

Coal Geology & Exploration

Objective Operations in a narrow space pose a challenge to rescue in the case of the collapse of mine roadways or tunnels. To address this challenge, this study developed a modular rescue casing while drilling (CwD) rig system for horizontal boreholes. With the capacity for quick responses, this CwD rig was designed to enhance the rescue efficiency and safety under complex geological conditions. Methods Following the modular design concept and compact layout principle, this study optimized core components such as the power heads, feed devices, and power system. The auxiliary operation vehicle was checked against overturning through multibody dynamics (MBD) …

Structural Optimization For Transfer Chutes Based On Energy Dissipation Mechanisms Of Coal Particles, Shi Yaocheng, Zou Zujie, Wen Guojun, Cheng Siyi, Wu Laijie, Wang Yudan, Liu Pu, Chen Mengxi

Coal Geology & Exploration

Objective Bulk material transport in emergency rescue scenarios and coal transportation poses stringent demands for the structural performance of transfer chutes. Given this, from the perspective of the energy dissipation mechanisms of particles, this study proposed structural optimization methods for transfer chutes based on the regulation of particle energy dissipation. Methods An experiment–simulation integrated analysis framework was established. Using this framework, this study systematically simulated the impact process of particles between two-stage walls I and Ⅱ using the discrete element method (DEM), highlighting the coupling mechanisms among velocity fluctuations, stress distribution, and energy transformation pathways. Based on the results, this …

A Simulation And Experimental Study Of Bottomhole Flow Field In A Large-Diameter Rescue Borehole, Zhao Yan, Liu Songhe, Hao Shijun, Zhao Jiangpeng, Li Peishu, Wang Xuebo, Yu Yongping, Gao Ke, Dong Bo, Zhang Bo

Coal Geology & Exploration

Objective In mine rescue, reaming using a large-diameter down-the-hole (DTH) hammer faces is challenged by complex bottomhole flow fields and difficult slag discharge. This study aims to address these challenges. Methods To reveal the influence patterns of drilling parameters on the bottomhole flow field and slag discharge efficiency, this study determined the optimal drilling parameter combination. Then, using the computational fluid dynamics (CFD)-discrete phase model (DPM) method, this study established a numerical model for the slag discharge and bottomhole flow field during the reverse circulation drilling using a DTH hammer. Relying on this model, this study analyzed the variation patterns …

Constructions Of Compact Dupin Hypersurfaces With Non-Constant Lie Curvatures, Thomas E. Cecil

Mathematics and Computer Science Department Faculty Scholarship

A hypersurface M in the unit sphere Sⁿ ⊂ Rⁿ⁺¹ is Dupin if along each curvature surface of M, the corresponding principal curvature is constant. If the number g of distinct principal curvatures is constant on M, then M is called proper Dupin. In this expository paper, we give a detailed description of two important types of constructions of compact proper Dupin hypersurfaces in Sⁿ. One construction was published in 1989 by Pinkall and Thorbergsson [35], and the second was published in 1989 by Miyaoka and Ozawa [26]. Both types of examples have the …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Injection-Production Process Parameters Of Well Group Configurations For Autothermic Pyrolysis In Situ Conversion Of Oil Shale, Zeng Yijian, Zhu Chaofan, Li Yanwei, Shui Haoche, Guo Wei

Coal Geology & Exploration

Background A well group acts as a multi-well synergistic unit, and its configuration directly determines both the selection of optimal injection–production process and the utilization efficiency of stratigraphic conditions, ultimately affecting the overall performance of resource recovery. Methods Using numerical simulations, this study assessed the performance of autothermic pyrolysis in situ conversion (ATS) under three vertical well group configurations: one injection well and one production well (1I1P), one injection well surrounded by four production wells (1I4P), and one injection well surrounded by six production wells (1I6P). Furthermore, it revealed the synergistic mechanisms between well group configuration and energy efficiency. Results …

Attenuation Characteristics And Wave Impedance Inversion Of Depth-Domain Nonstationary Seismic Data, Ma Ming, Ma Feng

Coal Geology & Exploration

Background The efficient application of depth migration methods has enabled the extensive implementation of depth-domain seismic data interpretation. Previous studies on the impacts of time-to-depth conversion and velocity models merely determine that an increase in depth corresponds to reduced dominant wavenumber of seismic waves and waveform stretching, without considering the changes in amplitude and phase. Objective This study aims to accurately characterize the waveforms of nonstationary seismic signals in the depth domain and enhance the impedance inversion accuracy. Methods First, based on energy dissipation and frequency dispersion effects during the propagation of seismic waves, this study investigated the complex mapping …

Analysis Of The Connotation Of Hidden Disaster-Causing Factors In Coal Mines And The Key Points Of Their Reconnaissance, Lian Huiqing, Wang Xu, Yin Shangxian, Xia Xiangxue, Cao Min, Li Qixing, Wu Xiaoming, Zhang Bin, Wang Yangyu, Zhang Qing, Wang Guo’An

Coal Geology & Exploration

Background To systematically normalize the reconnaissance of hidden disaster-causing factors in coal mines, the National Mine Safety Administration issued the Specification for General Survey of Hidden Disaster-causing Factors in Mine in 2024. Nevertheless, coal mining enterprises still face a range of notable issues in reconnaissance of hidden disaster-causing factors, including ambiguous connotations of the factors, broad scopes of reconnaissance, unclear implementation stages, a disjunction between explorations and reconnaissance, and improper conclusion descriptions. These problems severely restrict scientific and operational reconnaissance.Methods This study reviews the history of research on the reconnaissance of hidden disaster-causing factors, presents a summary of significant …

Molecular Simulations Of Selective Adsorption Of Lithium In The No.6 Coal Seam, Junggar Coalfield, Zhang Junshuang, Sun Beilei, Zhang Bin, Liu Chao

Coal Geology & Exploration

Objective With the discovery of metal deposits in coal-bearing strata, the distribution and occurrence patterns of lithium in coals have attracted much attention. However, its partitioning mode between organic structures and minerals in coals remains poorly understood.Methods This study investigated typical coals with a high lithium content in the Junggar Coalfield in Inner Mongolia. By integrating multiple simulation methods, including quantum mechanics, Monte Carlo simulation, and molecular dynamics, this study established the structural models of organic matter and inorganic minerals, as well as a visualized lithium-coal molecular structure model. Accordingly, it investigated the preferential adsorption sites on both organic …

Molecular Simulation Of Adsorption And Diffusion Behaviors Of High-Concentration Helium In Salt Cavern Storage Reservoirs, Chen Zeya, Wanyan Qiqi, Liu Mancang, Liu Xiaoqiang, Chen Jianfa, Li Kang, Wu Jianan, You Bing

Coal Geology & Exploration

Background Artificial salt cavern underground helium storage is the optimal approach for achieving long-term, large-scale strategic helium storage and represents an essential solution for establishing an autonomous, controllable helium supply system. The core challenge currently constraining China’s development of salt cavern underground helium storage facilities lies in the sealing capacity of salt rock against high-concentration helium (helium volume fraction ≥70%). Methods Molecular dynamics simulation was used in this study, a composite model of salt rock slit pore and channel pore was constructed to reveal the influences of temperature-pressure conditions, helium concentration, and pore fluid properties on the occurrence state and …

Source And Primary Factors Controlling Differential Enrichment For Helium In The Dongping Gas Field, Qaidam Basin, Xu Zhusong, Li Jian, Wang Xiaobo, Cui Huiying, Xia Yutian, Tian Jixian, Li Wanting, Chen Dawei

Coal Geology & Exploration

Background In recent years, promising helium-rich natural gas shows have been discovered in the Dongping gas field. However, the helium resources in the gas field exhibit lateral heterogeneity and vertical differential accumulation in multiple sequences, which restrict the further exploration of these resources. Methods By analyzing the lateral and vertical distribution characteristics of helium in the Dongping gas field, this study explored its origin and sources, analyzed the differences in geological backgrounds between helium-rich and helium-deficient gas reservoirs, and systematically summarized the differential enrichment pattern across different blocks within the Dongping gas field.Results and Conclusions In the Dongping gas …

Water Filling Intensity Assessment Of A Coal Seam Roof In The Dahaize Coal Mine, Northern Ordos Basin, Liu Xi, Ding Xiang, Huang Haiyu, Li Zhaoyang, Li Zhe, Zheng Sheng

Coal Geology & Exploration

Background Assessing water filling intensity in coal seam floors lays a foundation for the prevention and control of water hazards in mines. However, in the Jurassic coalfield in the northern Ordos Basin, complex hydrogeological structures and sedimentary heterogeneity pose severe challenges to traditional evaluation methods. Methods This study investigated the water hazard characteristics in the superimposed aquifers of the Jurassic Yan’an and Zhiluo formations in the Dahaize Coal Mine in northern Shaanxi. The purpose is to establish a zoning and assessment system of water filling intensity that is suitable for continental sedimentary settings and to provide a scientific basis for …

Solutions For Linear Fractional Differential Equations With Multiple Constraints Using Fractional B-Poly Bases, Md. Habibur Rahman, Muhammad I. Bhatti, Nicholas Dimakis

Physics & Astronomy Faculty Publications

This study presents an innovative numerical method for solving linear fractional differential equations (LFDEs) using modified Bernstein polynomial bases. The proposed approach effectively addresses the challenges posed by the nonlocal nature of fractional derivatives, providing a robust framework for handling multiple initial and boundary value constraints. By integrating the LFDEs and approximating the solutions with modified fractional-order Bernstein polynomials, we derive operational matrices to solve the resulting system numerically. The method’s accuracy is validated through several examples, showing excellent agreement between numerical and exact solutions. Comparative analysis with existing data further confirms the reliability of the approach, with absolute errors …

Re: Butte Priority Soils Operable Unit (Bpsou) Final Insufficiently Reclaimed Sites Field Sampling Plan (Fsp): Bres No. 26 – Cripple Dump, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Standing Waves Of Schrödinger Equation With Constant Magnetic Field And Combined Power Nonlinearities, Zhaosheng Feng, Yu Su

School of Mathematical & Statistical Sciences Faculty Publications

We study standing waves of the Schrödinger equation with constant magnetic field and combined power nonlinearities, which describes a single non-relativistic quantum particle in the presence of an electromagnetic field. We develop the local minima geometry method to establish the existence, estimates and mass collapse results for this equation, which generalize exiting results in the literature.

Characteristics And Formation Processes Of Helium-Bearing Gas Reservoirs In Deep Strata In The Xujiaweizi Fault Depression, Songliao Basin, Ren Jiahao, He Yanxin, Tian Wei, Wang Lei

Coal Geology & Exploration

Objective and Method The Xujiaweizi Fault Depression in the Songliao Basin contains multiple helium-bearing gas fields. However, the assessment methods for helium resources and helium accumulation patterns in the fault depression are yet to be determined. Using 3D seismic data and logs from 24 wells, this study optimized the helium resource assessment method based on natural gamma-ray spectral logging. Using the optimized method, this study quantitatively assessed the helium-generating potential and theoretical helium production of crust-derived helium in deep strata in the Xujiaweizi Fault Depression. By combining the geochemical characteristics of the helium-bearing gas reservoirs and the simulation results of …

Diagnosis, Prevention, And Control Of Liquid Accumulation In Horizontal Wellbores For Deep Coalbed Methane: A Case Study Of The Daning-Jixian Block Along The Eastern Margin Of The Ordos Basin, Zeng Wenting, Wang Zhiming, Zhang Lei, Tian Zhida, Zhen Huaibin, Dai Anna, Zeng Quanshu, Sui Tianyang

Coal Geology & Exploration

Objective The Daning-Jixian block on the eastern margin of the Ordos Basin has achieved large-scale production of deep coalbed methane (CBM), with nearly 150 horizontal wells having been put into production. However, with a gradual decrease in formation energy during CBM production, gas wells exhibit declining liquid-carrying capacity. Consequently, liquid accumulation in wellbores has become a major factor affecting deep CBM production. Recovery of deep CBM shows the coexistence of free and desorbed gases, accompanied by significantly varying gas/liquid ratios. Moreover, gas production channels and techniques vary in different production stages. Hence, there is an urgent need to develop a …