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Home On The Range: Where Deer And Antelope Compete With Feral Horses For Limited Resources, Katelyn Davies, Hannah B. Klugman, Kathryn A. Schoenecker, David C. Stoner

All Current Publications

Given projections for continued drought conditions in the West, a better understanding of how native wildlife respond to competition with feral horses will be critical for developing effective conservation programs in the future. This fact sheet provides information on feral horses and presents study data comparing their use of water resources with that of native wildlife.

Oco-3 Meets Ecostress: Insights Into Ecosystem Diurnal Water-Use Efficiency From Co-Located Solar-Induced Fluorescence And Thermal Observations, Zoe Amie Pierrat, Thomas P. Kurosu, Abhishek Chatterjee, Joshua B. Fisher, Maggie Johnson, Le Kuai, Kanishka Mallick, Nicholas Parazoo, Benjamin Wiebe, Kerry Cawse-Nicholson

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Terrestrial ecosystem regulation of carbon and water fluxes is critical for constraining climate–biosphere feedbacks but remains poorly quantified across space and time. Here, we evaluate whether co-located observations from NASA's Orbiting Carbon Observatory-3 (OCO-3) and the ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) can reproduce ecosystem water use efficiency (WUE) dynamics observed at FLUXNET sites across temporal scales, vegetation types, climates, and drought conditions. We created the ECOCO3 data set, which harmonizes OCO-3 and ECOSTRESS observations in space and time. ECOCO3 captures broad seasonal and diurnal carbon and water flux patterns including midday drought responses. Sampling sensitivity analysis …

Characterization Of Combined Adsorption Using Fermi Levels, Molecular Dynamics, And Monte Carlo Simulations To Prevent Cu–Zn (111) Alloy Corrosion, Mushtaq Jerri Meften, Ammar Abdul Jabbar Kadhim, Mohammed Shafeeq Abed

Makara Journal of Science

Experimentally developing corrosion inhibitors requires a significant amount of money and time. In silico advancement empowers selecting inhibitor molecules based on their properties derived from theoretical studies, thereby reducing costs. Our main approaches include theoretical studies such as Fermi levels, electrostatic potential surface (EPS), Fukui indices, molecular dynamics stimulations, and Monte Carlo as indispensable tools to investigate the adsorption mechanisms of molecules 6-((5-(((3S,5R)-2-oxo-5-((2-(pyrazin-2-yloxy) thiazol-5-yl) thio) tetrahydro-2H-thiopyran-3-yl) oxy)isothia-zol-3-yl)thio) nicotinic acid (PTT), and (S)-2-((5-((6-((3-(2-thioxoethoxy)-1,2,4-thiadiazol-5-yl)thio)-1,6-dihydropyra-zin-2-yl)oxy)-1,3,4-thiadiazol-2-yl) thio) acetaldehyde (TTD) on the Cu/Zn (111) alloy. We electronically characterized PTT and TTD, which were proven effective inhibitors. Notably, all results suggested that the two exhibited high …

Increasing The Density Value Of Composite Propellant Ap/Htpb/Al For Rocket Performance Using The Sphere Packing Model, Muhammad Iqbal Alfikri, Bayu Prianto, Ariadne Lakshmidevi Juwono

Makara Journal of Science

This research employs the sphere packing volume (SPV) model to optimize the density of composite propellants thereby enhancing rocket performance. We systematically varied the diameters of spherical ammonium perchlorate (AP) particles (50 and 400 µm) and aluminum powder (Al) particles (10 and 30 µm). These particles were incorporated at an ideal AP:Al ratio of 4:1 into a matrix of hydroxyl-terminated polybutadiene and toluene diisocyanate. By adjusting the AP ratio for each Al particle size and considering theoretical and tap densities, we precisely calculated the SPV value for each composition. The composition with the highest SPV value yielded remarkable results. This …

Impact Of Disturbances On Butterfly Communities At The Forest Edge Of Bukit Mas Village, North Sumatra, Indonesia, Nurhayati Nurhayati, Mufti Petala Patria, Nurul Winarni, Fairuz Husna

Makara Journal of Science

Biotic homogenization can negatively impact ecosystem function and stability, reducing species diversity and interac-tions. Although deforestation has declined in Gunung Leuser National Park since 2011, associated pressures still operate at various places within the park, possibly leading to biotic homogenization. This study looked into the differences in butterfly diversity under three habitat types to understand their responses to various levels of disturbance, including en-vironmental factors. This research was carried out in September 2023 at the forest edge of the Bukit Mas Village, North Sumatra. We used the Point Count method; observations were made twice in the morning (08.00–12.00 h) and …

Lignin Valorization To Phenolic Compounds Over Metal Oxide-Modified Hierarchical Zsm-5 Zeolites Derived From Indonesian Minerals, Arnia Putri Pratama, Iman Abdullah, Yuni Krisyuningsih Krisnandi

Makara Journal of Science

Lignin, a key component of lignocellulosic biomass, offers significant potential as a renewable raw material for the sustainable production of aromatic chemicals. To investigate its heterogeneous catalytic depolymerization, benzyl phenyl ether (BPE) was used as a model compound. Hierarchical ZSM-5 catalysts were synthesized and modified with metal oxides (NiO and CuO). Belitung kaolin and Bayat natural zeolite, natural minerals from Indonesia, were used as silica and alumina sources to synthesize hierarchical ZSM-5 zeolite (labeled as ZSM-5N), which was compared with hierarchical ZSM-5 synthesized using pro-analysis precursors (labeled as ZSM-5S). Comprehensive physicochemical characterization using FTIR, XRD, BET, XRF, SEM-EDX, and NH₃-TPD …

Dense Platinum Nanoparticles Confined In Mn-N-C Nanocages For Robust Heavy-Duty Pemfcs, Lei Zhao, Zhen-Min Cao, Jia-Yu Zuo, Ming-Liang Yang, Hong-Yan Qiao, Jun-Song Chen, Rui Wu

Journal of Electrochemistry

High-loading Pt cathodes are essential for heavy-duty proton exchange membrane fuel cells but suffer from a critical tradeoff between ionomer sulfonate poisoning and nanoparticle instability. Herein, we report a spatial confinement strategy to encapsulate dense Pt nanoparticles (~51.8 wt%) within Mn/N-co-doped mesoporous carbon nanocages (denoted as Pt-MnNC). This architecture excludes bulky ionomers to create an ionomer-shielded environment against sulfonate poisoning, while Mn-N_x-mediated strong metal-support interactions anchor the Pt nanoparticles to prevent agglomeration and further boost durability. In the 5 × 5 cm² membrane electrode assembly tests, the Pt-MnNC catalyst delivers an exceptional power density of 1.26 W·cm …

Engineering Small-Sized Cations With Strong Solvation For High-Voltage Supercapacitors, Tong Huo, Pan Liu, Hao Chen, Peng Zhang, Zhen-Lei Chen, Guo-Fu Sun, Zhi-Qiang Shi, Jing Wang

Journal of Electrochemistry

Supercapacitors (SCs) have attracted much attention in the field of energy storage due to their high power density and long cycle life. However, their relatively low energy density limits their application in a wider range of fields. Methods to increase energy density include enhancing specific capacitance and extending operating voltage window. Herein, we report a novel electrolyte salt, tetramethylammonium bis(fluorosulfonyl)imide (TMA-FSI), the resulting electrolyte formed with propylene carbonate (PC), designated as TMF, exhibited a wide electrochemical stability window (ESW) of 5.09 V. On the one hand, we found that the small size of TMA⁺ enables it to enter the …

Evaluating Peak Metamorphic Conditions Of The Kyanite-Bearing Rocks At Willis Mountain, Virginia, Usa, Emma J. Hunt, Peter Horvath, Connor R. Gregory, Jade D. Sabillon, Ethan H. Watson

Earth and Environmental Sciences Publications

Willis Mountain, near Dillwyn in central Virginia, is the world’s largest kyanite deposit located in the Chopawamsic Fm. of the Piedmont province. However, little is known about the temperature and pressure conditions under which the kyanite deposit and its surrounding rocks formed, compared with similar-aged rocks in the Blue Ridge province to the southwest. Willis Mountain is composed of kyanite-bearing muscovite schists to kyanite quartzites which contain up to 55% kyanite. The following methods were used to evaluate the metamorphic conditions, with multiple calibrations for each: phase equilibrium modelling; trace element thermometry (titanium in quartz and zirconium in rutile); garnet-biotite …

Efficient Acidic H2O2 Electrosynthesis Over Co Atoms Anchored On Nitrogen-Doped Hierarchical Porous Carbon, Xiao Huang, Zi-Hao Zhan, Hao-Xu Niu, Guan-Yu Luo, Jin-Tao Huang, Bo-Xuan Jin, De-Li Wang

Journal of Electrochemistry

The two-electron oxygen reduction reaction (2e⁻ ORR) presents a promising route for the on-site production of hydrogen peroxide (H₂O₂), offering a green alternative to energy-consuming anthraquinone process. However, the high selectivity toward the competing 4e⁻ ORR over the desired 2e⁻ pathway leads to low Faradaic efficiency for H₂O₂, posing a critical challenge in catalyst design. In this work, a nitrogen-doped hollow hierarchical porous carbon with anchored Co atoms (CoN/HPC) was constructed for high-performance H₂O₂ production. The as-prepared Co-N/HPC catalyst showed excellent 2e⁻ ORR performance, achieving …

Generalized Apostol-Bernoulli Functions And The Evaluation Of Character Sums, Brad Isaacson

Publications and Research

We introduce two types of generalized Apostol–Bernoulli functions attached to Dirichlet characters and express them by generalized Apostol–Bernoulli numbers. As a corollary, we obtain formulas expressing two families of character sums by generalized Apostol–Bernoulli numbers. These sums are twisted generalizations of sums introduced and studied by Arakawa, Berndt, Ibukiyama, Kaneko, Kim, Ramanujan, and Zaharescu in the context of modular forms and theta function identities.

Geotechnical Enhancement Of Noncohesive Coal Mine Overburden Using Microbially Induced Calcite Precipitation And Fly Ash Stabilization For Sustainable Pavement Applications, Atul Gautam, Laxmikant Yadu

Journal of Sustainable Mining

The majority of the waste generated from opencast mining, termed as overburden (OB), is dumped adjacent to the mine boundary and poses long-term stability issues. Various studies have been carried out to assess the risk of dump slope failure, and treatment strategies have been accordingly recommended to strengthen this OB dump. However, scant works are reported to sustainably utilize this OB for construction works. This study aims to quantify the performance of stabilized noncohesive coal mine OB collected from Gondegaon opencast mine (OCM) in India. Stabilization was achieved using two techniques, namely microbially induced calcite precipitation (MICP) through Sporosarcina pasteurii …

Re: Approval Letter For The Butte Priority Soils Operable Unit Draft Final Reclamation Improvement Field Sampling And Investigation Plan: Bres No. 135 – Washoe Sampling Works, Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Approval Letter For The Butte Priority Soils Operable Unit Draft Final Reclamation Improvement Field Sampling And Investigation Plan: Bres No. 105 – Lizzie Shaft, Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Evaluating Atmospheric Nox In The Marine Boundary Layer Near Tampa Bay, Ben Lloyd '25, Anson Kirsch, Samuel Irvine, Yasin Elshorbany, James Ivey

Student Research

Nitrogen oxides (NOX), including nitric oxide (NO) and nitrogen dioxide (NO₂), are atmospheric constituents that can contribute to nitrate deposition in seawater. Since nitrate availability can influence marine ecosystems, understanding atmospheric nitrogen inputs is important for characterizing nitrogen cycling in coastal environments. This dataset contains atmospheric NO and NO₂ measurements collected from July 5–6, 2023, in the marine boundary layer near Tampa Bay, Florida, at the University of South Florida St. Petersburg campus using a Teledyne T200UP Analyzer.

The dataset provides observations of atmospheric nitrogen oxide concentrations that can be compared with measurements of nitrate in rainwater and seawater to …

Re: Approval Letter For The Butte Priority Soils Operable Unit Draft Final Reclamation Improvement Field Sampling And Investigation Plan: Bres No. 46 – Missoula Mine, Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Approval Letter For The Butte Priority Soils Operable Unit Draft Final Insufficiently Reclaimed Sites Field Sampling And Investigation Plan: Bres No. 11 – Magna Charta Lessee Dumps, Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Approval Letter For The Butte Priority Soils Operable Unit Draft Final Insufficiently Reclaimed Sites Field Sampling And Investigation Plan: Bres No. 1503 – Hornet Addition, Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Re: Approval Letter For The Butte Priority Soils Operable Unit Draft Final Reclamation Improvement Field Sampling And Investigation Plan: Bres No. 129 – Heaney Dump, Molly Roby

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

Ai In Higher Education: Some Notes From The Front, Debra Rienstra

University Faculty Publications and Creative Works

We’re four weeks into the semester now. This past summer, our university unveiled a campus-wide AI policy that exhorts students and faculty to use discernment and tries to lay out some rules about security. Meanwhile, we have purchased a campus-wide subscription to an AI aggregator tool now available to all students, faculty, and staff (in part, from what I understand, as an attempt to effect some boundaries). And then, in the news, all this hand-wringing over the end of humanity, etc., on the one hand and techno-utopian promises on the other.

When Three Points Aren't Enough: Parameter Estimation In Newton's Law Of Cooling, Alberto A. Condori, Cara D. Brooks, Madeline R. Goldberg

CODEE Journal

We begin with a paradoxical three-point problem where the standard parameter estimation formula fails because temperature data must satisfy a concavity condition reflecting Newton's Law of Cooling's exponential structure. Although a closed-form solution for A exists for equally-spaced measurements, high sensitivity to error motivates the use of overdetermined systems with many measurements. The "profiling over A" technique transforms this three-parameter nonlinear problem into a sequence of simple linear regressions, providing computational efficiency and conceptual transparency. This approach can be generalized to many parameter estimation problems in science and engineering, making it a valuable tool for undergraduates interested in applied mathematics. …

Powers' Conjecture On The Third Largest Eigenvalue Of A Graph, Kevin Schmidt

Master's Theses

In 1989, David Powers conjectured that for any connected graph G on n vertices, the k-th largest eigenvalue of the adjacency matrix satisfies λk(G) ≤ ⌊n/k⌋ for every 1 ≤ k ≤ n/2. The conjecture has since been resolved case by case, in the sharper form λk(G) ≤ n/k − 1: the case k = 1 is classical, k = 2 was settled independently by Hong and by Powers in 1988, and k ≥ 4 was shown to fail by Nikiforov and Linz. This thesis surveys the resolution of the remaining case, k = 3, achieved in March 2026 by …

Complementary Thermodynamic Mechanisms Of Boron And Carbon Segregation At Grain Boundaries In Nickel Alloys, Tyler D. Dolezal, Rodrigo Freitas, Ju Li

Faculty Publications

Grain boundary stabilization by light interstitials is central to the performance of Ni-based superalloys, yet the thermodynamic mechanisms governing their interactions with substitutional chemistry remain poorly resolved. Here, we use hybrid Monte Carlo molecular dynamics simulations to quantify how boron and carbon modify the thermodynamic, structural, and chemical ordering of grain boundaries in Ni-Cr alloys. By analyzing interfacial state variables, site-resolved segregation spectra, local chemical ordering, and structural evolution, we show that boron and carbon stabilize grain boundaries through complementary pathways. Carbon drives saturation-controlled stabilization by recruiting Cr and conditioning boundary chemistry, while suppressing temperature-driven structural transformations of the boundary. …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Unique Connotation Of Geological-Engineering Dual Sweet Spot Evaluation For Effective Coalbed Methane Exploitation, Luo Pingya, Zhu Suyang

Coal Geology & Exploration

Objective In China, the exploitation of deep and shallow coalbed methane (CBM) still relies on the evaluation approach oriented to the geological-engineering dual sweet spots of unconventional hydrocarbons. However, exemplary CBM production technologies delivered unsatisfactory performance in other blocks and failed to find wide application even in zones with overlapping geological and engineering sweet spots. This issue represents the principal theoretical and technical challenge confronting the comprehensive development of the CBM industry in China. Methods This study aims to elucidate the causes of this issue and provide corresponding solutions, as well as clarifying the conditions for the effective linkage between …

Exploration And Prospects Of Engineering Technologies For Deep Coal Seam Development Based On The Well Factory Mode, Gao Deli, Dong Xuelin, Bi Yansen

Coal Geology & Exploration

Background Given China's energy and mineral resource endowment, the efficient and green development and utilization of deep coal resources are expected to become a significant strategic option for facilitating the country's green energy transition and achieving its goals of peak carbon dioxide emissions and carbon neutrality. This significant demand may be satisfied through development using a structurally complex well factory mode. Method This study introduces the basic concept of a three-dimensional, multi-functional, and precisely controllable underground structurally complex well factory, designed for the efficient and green development of unconventional energy and mineral resources. It then discusses the well factory engineering …

Differential Accumulation Of Coalbed Methane In Medium- To Low-Rank Coal Seams In A Strongly Compressional Tectonic Setting In The Tarim Basin, Liu Honglin, Wang Hongyan, Wang Haichao, Deng Ze

Coal Geology & Exploration

Background The Tarim Basin contains abundant coal and coalbed methane (CBM) resources. However, the geological accumulation patterns of CBM in the basin remain poorly understood. This leads to a relative lack of targeted technologies for the exploration and development of both deep coal reservoirs and steeply dipping coal seams, further rendering it challenging to achieve breakthroughs in CBM development in the basin. Methods Based on test data from 92 coal samples, data on the drilling and production tests of more than 10 exploration wells, and 3D seismic interpretation results, this study systematically investigated the distribution of coal-bearing strata, as well …

Variable-Temperature And Variable-Pressure Adsorption Characteristics Of Deep Coalbed Methane And Their Implications, Jiang Wenping, Sun Siqing, Jin Xianglan, Tian Bofan, Tian Xinjuan

Coal Geology & Exploration

Background Investigating the adsorption characteristics of coalbed methane (CBM) helps bridge key geological information concerning deep CBM, including occurrence state, free gas proportion, and gas-bearing properties, with the gas production potential and commercial exploitation of CBM wells. Such investigation represents a key component of the evaluation, exploration, and exploitation of CBM reservoirs. Methods Using deep coal samples collected from three representative regions, this study designed high-temperature and high-pressure methane isothermal adsorption experiments, together with variable-temperature and variable-pressure methane adsorption experiments, using nuclear magnetic resonance (NMR). The adsorption characteristics of the coal samples derived using the different experimental methods were subsequently …

Occurrence Pattern Of Adsorbed And Free Gas In Deep Coal Seams Under The Control Of Pore Structure: A Case Study Of The No. 8 Coal Seam In The Daning-Jixian Block Along The Eastern Margin Of The Ordos Basin, Bian Liheng, Shen Jian, Shi Rui, Zhang Wei, Ma Zhuang, Liang Xuemin, Dong Jiying, Zhu Peipei, Ma Tianyu

Coal Geology & Exploration

Background Deep coalbed methane (CBM) holds an important strategic position in China's unconventional natural gas system. However, concerning deep CBM occurrence, there remains a lack of systematic quantitative understanding of the underlying mechanisms and the controlling effects of pore structure. Methods This study investigated high-rank coal samples collected at a burial depth of approximately 2000 m from the No. 8 coal seam in the Daning-Jixian block along the eastern margin of the Ordos Basin. Using multiscale pore characterization techniques, including low-temperature liquid nitrogen adsorption, high-pressure mercury injection, and low-temperature CO₂ adsorption, the full-scale pore size distribution of the coal …

Controlling Effects Of Ash Yield On The Adsorption-Desorption Behavior And Production Potential Of Methane In Deep Coal Reservoirs, Huang Daojun, Liu Xinshe, Chen Shida, Sun Wen, Jiao Pengshuai, Wang Huaichang

Coal Geology & Exploration

Objective The lithotype and quality characteristics of coals significantly affect the reservoir permeability and production potential of coalbed methane (CBM). However, there remains a lack of clear understanding of the controlling effects of ash yield on the gas-bearing properties and methane adsorption-desorption behavior of coal seams under comparable thermal maturity. Focusing on coal samples obtained through continuous sealed coring from the No. 8 coal seam in well M172 in the east-central part of the Ordos Basin, this study aims to clarify the impacts of ash yield on the pore structure, adsorption capacity, desorption process, and resource recoverability. This effort is …