Digital Commons Network^™

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 …

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 …

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 …

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.

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.

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.

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 …

Components And Isotope Fractionation Of Deep Coalbed Methane And Their Geological Implications In The Daning-Jixian Block, Ordos Basin, Wang Chengwang, Zhang Yun, Wang Hongna, Chen Yiyu, Chen Gaojie, Wang Jun, Liu Lingqi, Li Panxue, He Hongcheng, Li Wenbiao

Coal Geology & Exploration

Objective The components of deep coalbed methane (CBM), along with its isotopic composition and fractionation patterns, hold great significance for revealing the genetic types, occurrence characteristics, flow, and production patterns of CBM. Methods This study investigated the Shanxi and Benxi formations in the Daning-Jixian block, Ordos Basin. A range of analyses and tests were conducted, including field CBM desorption experiments on coal samples from the deep parts of both formations, continuous monitoring of wellhead gas from two production wells, physical property tests on the samples, organic petrological experiments, and geochemical analysis. Furthermore, this study analyzed the components and isotopes of …

Investigating The Mechanisms Controlling Gas Flow In Coal Reservoirs Based On Multi-Scale Digital Rocks, Han Lei, Huang Dongxiang, Zhang Xiaodong, Shen Jian, Zhang Shuo, Ni Xiaoming, Liu Xiao

Coal Geology & Exploration

Background Deep coal reservoirs exhibit highly heterogeneous pore-fracture structures. However, limited by a single imaging resolution, conventional digital rock techniques struggle to characterize complex pore-fracture networks across multiple scales. This poses significant scientific challenges for the fine-scale characterization of deep coal reservoirs and the investigation of their seepage mechanisms. Methods This study investigated deep coalbed methane (CBM) reservoirs in the north-central Qinshui Basin. The pore-fracture structures of coal samples were characterized by integrating X-ray computed tomography (CT), mercury injection capillary pressure (MICP), and scanning electron microscopy (SEM). Digital rock models incorporating multi-scale pores and fractures were then constructed by integrating …

Investigating The Characteristics Of Ch4 Adsorption In Coal Reservoirs Based On Interpretable Machine Learning, Chen Ruibin, Zhou Sandong, Zhang Weixin, Yan Detian, Wang Hua

Coal Geology & Exploration

Objective Accurately predicting methane (CH₄) adsorption capacity in coal reservoirs is critical to the efficient exploration and exploitation of coalbed methane (CBM). Existing studies largely rely on experimental data from a small number of samples and theoretical adsorption models such as Langmuir. However, these studies exhibit time-consuming and laborious processes, as well as conclusions with limited generalizability, posing challenges to their widespread applications across different basins. Methods Based on 1150 sets of experimental data on CH₄ adsorption in coals, this study investigated five machine learning models, namely artificial neural network (ANN), support vector machine (SVM), K-nearest neighbor …

Mechanical Anisotropy And Depth Effects Of Deep Coal Seams, Mei Xiaofan, Wang Cong, Wang Kaifeng, Tang Shuheng, Zhang Songhang, Xi Zhaodong

Coal Geology & Exploration

Objective The mechanical properties of coal seams determine the stability, fracability, and fracturing performance of deep coal reservoirs. Since the in situ stress applied to coal increases with burial depth, deep coal differs from its shallow counterpart in damage behavior, key mechanical parameters, and failure mechanism. Furthermore, deep coal exhibits pronounced mechanical anisotropy.Methods Focusing on the No. 9 coal seam in the Linxian area along the eastern margin of the Ordos Basin, this study carried out triaxial compression tests at 60℃ under different confining pressures to determine the mechanical anisotropy of deep coal. By comparing the full stress-strain curves, …

An Improved Brittleness Characterization Method For Deep Coalbed Methane Reservoirs And Its Application To Well Logs, Huang An’Er, Gong Fei, Peng Suping, Zou Guangui, Zhang Zhaoji, Wu Yiquan, Rong Zhihong, Li Qingrun

Coal Geology & Exploration

Background Deep coalbed methane (CBM) reservoirs are characterized by high pressure, low porosity, and low permeability. Therefore, large-scale volume fracturing is required for their commercial development. As an important engineering sweet spot parameter for selecting optimal fracturing targets, the brittleness index can reflect the difficulty in generating complex fracture networks during fracturing. However, existing brittleness characterization methods are largely applicable to strata with high brittle mineral content, such as shales and sandstones, while methods for characterizing the brittleness of deep CBM reservoirs with high organic matter content and low brittle mineral content are lacking. Methods Rock physics experiments on 20 …

A Fault Identification Method For Deep Coalbed Methane Reservoirs Based On An Improved Transunet, Gao Congshun, Wu Haibo, Liu Lei, Wang Zijian, Huang Xuanyu, Jia Lilan, Xu Aiguo

Coal Geology & Exploration

Objective Small-scale faults in deep coalbed methane (CBM) reservoirs significantly affect CBM enrichment and the deployment of development wells. However, deep seismic data tend to suffer from low signal-to-noise ratios (SNRs) and poor continuity of reflection events, while conventional methods are likely to miss small-scale faults. To address these limitations, this study proposes a fault identification method based on an improved TransUNet. Methods The proposed method is developed based on the R50-ViT-B_16 TransUNet architecture. A coordinate attention (CA) module is introduced before the skip connections enter the decoder to enhance the feature representation of the locations and directional continuity of …