Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 14731 - 14760 of 294488

Full-Text Articles in Physical Sciences and Mathematics

Benchtop-Scale High Temperature Molten Salt Electrochemical Reactors: Experimental Setup And Considerations, Haley Hoover, Ivy Wu, Oluwatamilore Olushina, Robert Bell, Kerry Rippy May 2025

Benchtop-Scale High Temperature Molten Salt Electrochemical Reactors: Experimental Setup And Considerations, Haley Hoover, Ivy Wu, Oluwatamilore Olushina, Robert Bell, Kerry Rippy

Reviews, Analyses, and Instructional Studies in Electrochemistry (RAISE)

Molten salt electrochemical reduction (MSER) is the dominant production method for aluminum and titanium, and emerging technologies for producing other commodity metals with these highly electrified techniques have demonstrated promising results. However, the scale up of MSER of materials such as iron and silicon are limited by the challenging issues of materials compatibility and impurity control. This work describes an experimental MSER setup using both chloride and carbonate salts. This setup is designed for operations outside of a glovebox, which is practical from an industrial perspective, but creates unique challenges. This work serves as a practical guide to discuss some …


Integrating A Stakeholder-Centric Approach Into Dynamic Adaptation Policy Pathways For Equitable Coastal Flood Risk Management In East Boston, Shailee M. Desai May 2025

Integrating A Stakeholder-Centric Approach Into Dynamic Adaptation Policy Pathways For Equitable Coastal Flood Risk Management In East Boston, Shailee M. Desai

Graduate Doctoral Dissertations

This research aims to illustrate a methodology incorporating diverse stakeholder values in adaptation planning to promote equitable outcomes using a hypothetical case study of the Lower Border Street area in East Boston, using the Dynamic Adaptive Policy Pathways (DAPP) framework for managing coastal flood risk. It offers three significant contributions to the field of adaptation planning: (i) It demonstrates how to integrate a stakeholder-specific assessment within the DAPP framework and illustrates individual impacts to a variety of stakeholders, including high- and low-income residents, commercial actors, government actors, and coastal landowners hoping that the planning process remains transparent and motivates local …


Investigating The Role Of Aerosols In Extreme Precipitation Events Along The Gulf Coast Of The U.S.A., Wenjia Cao May 2025

Investigating The Role Of Aerosols In Extreme Precipitation Events Along The Gulf Coast Of The U.S.A., Wenjia Cao

LSU Doctoral Dissertations

Atmospheric aerosols have been found to influence tropical cyclone (TC) and flood event development. In this study, the Weather Research and Forecasting model is applied to investigate specific microphysical impacts and aerosol sensitivity to heavy precipitation and TC events in the U.S. Gulf Coastal area. The Thompson aerosol-aware scheme with regular and adjusted aerosol concentration scenarios is used to quantify precipitation, wind field, horizontal/vertical structures, and track variations, by aerosol mixing ratio. In general, results for the three storms analyzed (the 2016 Baton Rouge, Louisiana, flood event (Chapter 2); Hurricane Harvey in 2017 (Chapter 3); and an idealized storm event …


Optimization Of Renewable Energy Systems: Comparative Analysis Of Advanced Algorithms And Photovoltaic-Electrolyzer Performance For Cost Reduction And Efficiency Enhancement, Mohamed-Amine Babay, Mustapha Adar, Ahmed Chebak, Mustapha Mabroukia May 2025

Optimization Of Renewable Energy Systems: Comparative Analysis Of Advanced Algorithms And Photovoltaic-Electrolyzer Performance For Cost Reduction And Efficiency Enhancement, Mohamed-Amine Babay, Mustapha Adar, Ahmed Chebak, Mustapha Mabroukia

Journal of Electrochemistry

The increasing demand for cost-effective and efficient renewable energy solutions presents significant optimization challenges in hybrid energy systems. This paper addresses these challenges by conducting a comparative analysis of three advanced optimization algorithms—Lévy Flight Optimization (LFO), Archimedean Optimization (AO), and Quantum Gorilla Optimization (QGO)—to minimize the Total Net Present Cost (TNPC) and Levelized Cost of Energy (LCOE) in hybrid renewable energy systems. The study integrates critical cost parameters such as Capital Expenditure (CAPEX), Operational Expenditure (OPEX), replacement costs, and salvage values into an advanced optimization framework. Three system configurations are evaluated: Wind Turbines and Fuel Cells (WT/FC), Photovoltaic Systems and …


Theoretical Insights Into The Atomic And Electronic Structures Of Polyperyleneimide: On The Origin Of Photocatalytic Oxygen Evolution Activity, Yi-Qing Wang, Zhi Lin, Ming-Tao Li, Shao-Hua Shen May 2025

Theoretical Insights Into The Atomic And Electronic Structures Of Polyperyleneimide: On The Origin Of Photocatalytic Oxygen Evolution Activity, Yi-Qing Wang, Zhi Lin, Ming-Tao Li, Shao-Hua Shen

Journal of Electrochemistry

Polymeric perylene diimide (PDI) has been evidenced as a good candidate for photocatalytic water oxidation, yet the origin of the photocatalytic oxygen evolution activity remains unclear and needs further exploration. Herein, with crystal and atomic structures of the self-assembled PDI revealed from the X-ray diffraction pattern, the electronic structure is theoretically illustrated by the first-principles density functional theory calculations, suggesting the suitable band structure and the direct electronic transition for efficient photocatalytic oxygen evolution over PDI. It is confirmed that the carbonyl O atoms on the conjugation structure serve as the active sites for oxygen evolution reaction by the crystal …


Large-Scale Groundwater System Characterization Using Pressure Responses To Barometric Perturbations Caused By The 2022 Hunga Tonga-Hunga Ha'apai Volcanic Eruption, Anhua He, Yang Liu, Fan Zhang, Huamei Zhang, Ramesh P. Singh, Yanzhang Wang May 2025

Large-Scale Groundwater System Characterization Using Pressure Responses To Barometric Perturbations Caused By The 2022 Hunga Tonga-Hunga Ha'apai Volcanic Eruption, Anhua He, Yang Liu, Fan Zhang, Huamei Zhang, Ramesh P. Singh, Yanzhang Wang

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Hunga Tonga-Hunga Ha'apai volcanic erupted on 15 January 2022, causing Lamb waves to propagate throughout the global troposphere. However, reports on volcanic eruptions–pressure fluctuations and water level dynamics are lacking. We quantified the propagation processes of Lamb waves induced by the Tonga volcanic eruption. Barometric pressure data collected at 1-min intervals at 485 meteorological stations in China showed that the eruption induced an atmospheric pressure event with an amplitude of ∼2 hPa over an hour and a wave speed of 295 m/s. Concomitant groundwater levels were available at 338 wells to find the barometric response to the volcanic event. The …


Protein Word Detection Using Text Segmentation Techniques, Ashish V. Tendulkar, Sutanu Chakraborti, Ganesh Devi May 2025

Protein Word Detection Using Text Segmentation Techniques, Ashish V. Tendulkar, Sutanu Chakraborti, Ganesh Devi

Journal of Global Awareness

Literature in Molecular Biology is abundant with linguistic metaphors. There has been works in the past that attempt to draw parallels between linguistics and biology, driven by the fundamental premise that proteins have a language of their own. Since word detection is crucial to the decipherment of any unknown language, we attempt to establish a problem mapping from natural language text to protein sequences at the level of words. Towards this end, we explore the use of an unsupervised text segmentation algorithm for the task of extracting "biological words” from protein sequences. We demonstrate the effectiveness of using domain knowledge …


Are Cycles Of Neural Activity The Algorithm Of The Brain?, Edwin Omondi Onyango May 2025

Are Cycles Of Neural Activity The Algorithm Of The Brain?, Edwin Omondi Onyango

Computer Science Senior Theses

We propose that precisely timed neural activity cycles can serve as structural primitives for memory and computation in a system that exhibits associative learning like the brain. Inspired by biologically grounded mechanisms such as calcium-dependent plasticity, spike-timing-dependent learning, and phase-sensitive excitability, we construct a spiking neural network model in which repeated temporal coincidences drive the formation of self-sustaining activity loops. These cycles, once formed, persist as dynamic memory traces: not stored as static weights, but as reverberating patterns that replay in time when these loops are restarted. We show that noise alone fails to induce stable structure, but even sparse, …


Some Studies On Information Set Decoding Algorithms And Universal Hash Functions, Sreyosi Bhattacharyya May 2025

Some Studies On Information Set Decoding Algorithms And Universal Hash Functions, Sreyosi Bhattacharyya

Doctoral Theses

This thesis presents some studies on Information Set Decoding algorithms and Universal Hash Functions. In the context of Information Set Decoding (ISD) the thesis studies time/memory trade-off of ISD algorithms and in the context of universal hash functions, the thesis studies design and efficient implementations of polynomial hash functions defined over prime order fields. A cornerstone of ISD algorithms is the algorithm proposed by Stern and it introduced the meet-in-the-middle collision search approach to ISD algorithms. Though this algorithm is more efficient in terms of asymptotic time complex- ity than the preceding algorithms proposed by Prange, Lee and Brickell and …


The Nitrogen-Vacancy-Nitrogen Color Center: A Ubiquitous Visible And Near-Infrared-Ii Quantum Emitter In Nitrogen-Doped Diamond, Brett C. Johnson, Mitchell O. De Vries, Alexander J. Healey, Marco Capelli, Anjay Manian, Giannis Thalassinos, Amanda N. Abraham, Harini Hapuarachchi, Tingpeng Luo, Vadym N. Mochalin, Jan Jeske, Jared H. Cole, Salvy Russo May 2025

The Nitrogen-Vacancy-Nitrogen Color Center: A Ubiquitous Visible And Near-Infrared-Ii Quantum Emitter In Nitrogen-Doped Diamond, Brett C. Johnson, Mitchell O. De Vries, Alexander J. Healey, Marco Capelli, Anjay Manian, Giannis Thalassinos, Amanda N. Abraham, Harini Hapuarachchi, Tingpeng Luo, Vadym N. Mochalin, Jan Jeske, Jared H. Cole, Salvy Russo

Chemistry Faculty Research & Creative Works

Photoluminescent defects in diamond, such as the nitrogen-vacancy (NV) color center, are at the forefront of emerging optical quantum technologies. Most emit in the visible and near-infrared spectral region below 1000 nm (NIR-I), limiting their applications in photonics, fiber communications, and biology. Here, we show that the nitrogen-vacancy-nitrogen (N2V) center, which emits in the visible and near-infrared-II (NIR-II, 1000-1700 nm), is ubiquitous in as-synthesized and processed nitrogen-doped diamond, ranging from bulk samples to nanoparticles. We demonstrate that N2V is also present in commercially available state-of-the-art NV diamond sensing chips made via chemical vapor deposition (CVD). In high-pressure high-temperature (HPHT) diamonds, …


2025 Revised Draft Final Insufficiently Reclaimed Sites Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc. May 2025

2025 Revised Draft Final Insufficiently Reclaimed Sites Quality Assurance Project Plan (Qapp), Pioneer Technical Services, Inc.

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


American Society Of Hematology/International Society On Thrombosis And Haemostasis 2024 Updated Guidelines For Treatment Of Venous Thromboembolism In Pediatric Patients, Paul Monagle, Muayad Azzam, Rachel Bercovitz, Marisol Betensky, Rukhmi Bhat, Tina Biss, Brian Branchford, Leonardo R. Brandão, Anthony K.C. Chan, Vincent E.S. Faustino, Julie Jaffray, Sophie Jones, Hassan Kawtharany, Bryce A. Kerlin, Nicole Kucine, Riten Kumar, Christoph Male, Marie Claude Pelland-Marcotte, Leslie Raffini, Chittalsinh Raulji, Sarah E. Sartain, Clifford M. Takemoto, Cristina Tarango, C. Heleen Van Ommen, Maria C. Velez, Sara K. Vesely, John Wiernikowski, Suzan Williams, Hope P. Wilson, Et Al May 2025

American Society Of Hematology/International Society On Thrombosis And Haemostasis 2024 Updated Guidelines For Treatment Of Venous Thromboembolism In Pediatric Patients, Paul Monagle, Muayad Azzam, Rachel Bercovitz, Marisol Betensky, Rukhmi Bhat, Tina Biss, Brian Branchford, Leonardo R. Brandão, Anthony K.C. Chan, Vincent E.S. Faustino, Julie Jaffray, Sophie Jones, Hassan Kawtharany, Bryce A. Kerlin, Nicole Kucine, Riten Kumar, Christoph Male, Marie Claude Pelland-Marcotte, Leslie Raffini, Chittalsinh Raulji, Sarah E. Sartain, Clifford M. Takemoto, Cristina Tarango, C. Heleen Van Ommen, Maria C. Velez, Sara K. Vesely, John Wiernikowski, Suzan Williams, Hope P. Wilson, Et Al

School of Medicine Faculty Publications

Background: The American Society of Hematology (ASH) guidelines on treatment of pediatric venous thromboembolism (VTE) were published in 2018. In the last 6 years, there has been a 10-fold increase in the number of children involved in VTE treatment trials. Objective: The ASH Committee on Quality and Guidelines agreed to update the pediatric guidelines in conjunction with the International Society on Thrombosis and Haemostasis (ISTH). These ASH/ISTH evidence-based guidelines are intended to support patients, clinicians, and other health care professionals in the management of pediatric patients with VTE. Methods: ASH/ISTH formed a multidisciplinary guideline panel to minimize potential bias from …


Soil Geochemistry Characteristics Of Bimodal-Mafic Type Vms Deposits In The Central Pontides: Importance Of Data Investigation In Exploration And Following Discovery, Buğra Çavdar, Kurtuluş Günay May 2025

Soil Geochemistry Characteristics Of Bimodal-Mafic Type Vms Deposits In The Central Pontides: Importance Of Data Investigation In Exploration And Following Discovery, Buğra Çavdar, Kurtuluş Günay

Turkish Journal of Earth Sciences

Çangaldağ Metamorphic Complex is defined with low grade metamorphic equivalents of mafic to felsic intrusive and extrusives, clastics and volcanoclastics. The Au-Cu-Zn Say Yayla (deeply-seated; West Zone) and the Au-dominant Büyük Hill (gossan related; East Zone) deposits are classified as bimodal-mafic type VMS in that complex and they are hosted in the metafelsic ensimatic arc volcanics. These were investigated by soil samples developed over each mineralization to examine the soil characteristics with different textural features. A total of 274 soil samples were collected and they have been geochemically analysed and examined using various statistical methods. The results reveal that both …


Integrated Geochemical, Geoelectrical, And Uav-Based Methods For Analyzing The Güzelyalı Landslide (Çanakkale, Türkiye), Oya Erenoğlu, Emi̇n Ulugergerli̇, R. Cüneyt Erenoğlu, Abdullah Akbaş, Ahmet Evren Ergi̇nal May 2025

Integrated Geochemical, Geoelectrical, And Uav-Based Methods For Analyzing The Güzelyalı Landslide (Çanakkale, Türkiye), Oya Erenoğlu, Emi̇n Ulugergerli̇, R. Cüneyt Erenoğlu, Abdullah Akbaş, Ahmet Evren Ergi̇nal

Turkish Journal of Earth Sciences

The number of reactivations increased in the Güzelyalı-Erenköy landslide area after 2013 in Çanakkale, Türkiye, where historical landslide activity has been recorded since 1875. This area is home to numerous summer residences and experiences ongoing slow-moving landslide activity along a 400-m-long slope, extending from the heavily trafficked Çanakkale-İzmir highway to the coastline. In this study, the nature of the reactivations was evaluated by considering the conditioning and triggering factors that contributed to the landslide. The evaluation was based on geochemical analyses, field observations, geoelectric measurements, and unmanned aerial vehicle (UAV) data. The results revealed that the sliding occurred along a …


Apatite Chemistry From The Xv Ioa Deposit, The Bafq–Saqand Metallogenic Province (Bsmp), Central Iran: Constrains On The Genesis Of Ioa Deposits, Sakine Amraei, Majid Ghasemi Siani, Mohammad Yazdi, Liang Qiu, Chang–Zhi Wu, Minghua Ren, Shahrokh Rajabpour May 2025

Apatite Chemistry From The Xv Ioa Deposit, The Bafq–Saqand Metallogenic Province (Bsmp), Central Iran: Constrains On The Genesis Of Ioa Deposits, Sakine Amraei, Majid Ghasemi Siani, Mohammad Yazdi, Liang Qiu, Chang–Zhi Wu, Minghua Ren, Shahrokh Rajabpour

Turkish Journal of Earth Sciences

In this study, we present petrographical and microanalytical (EPMA, LA–ICP–MS) results of apatites associated with Fe–Ti±P mineralization in the XV deposit in the BSMP. Apatite is predominantly observed as subhedral to euhedral, homogeneous grains, with no zoning or inclusions. Geochemically, apatite is fluorapatite of magmatic origin, with Cl/OH and Cl/F ratios of <0.05 and 0.01 to 0.07, respectively. Apatites from XV and other IOA deposits in the BSMP display a high F/Cl ratio, which is likely the main characteristic of IOA–type deposits such as the Kiruna-type deposit. Apatites from both rock types (gabbro and pyroxenite) exhibit similar rare earth elements (REEs) and multitrace element patterns, indicative of a shared origin. The highly light rare earth elements (LREEs)–enriched pattern in chondrite–normalized fractionation trends, along with positive Eu and slight negative Ce anomalies, as well the high (La/Sm)N and (La/Yb)N ratios of XV apatite, further corroborates the magmatic genesis of fluorapatite. The Eu/Eu* and Ce/Ce* ratios in XV rocks imply a high oxidation condition, as well as other IOA deposits in BSMP. The sulfur content is less than 1 wt% and shows a positive correlation with SiO2, implying coupled dissolution–reprecipitation of primary fluorapatite. Considering the geological setting of XV and other IOA deposits in the BSMP, the parental magma(s) appear to have originated from oxidizing Fe-Ti±P-rich magma(s), likely formed within an extensional postcollisional setting, influenced by the Proto–Tethys and Central Iranian Microcontinent (CIMC) convergence events.


First Record Of Scyphocrinoids In Türkiye And Recognition Of The Silurian/Devonian Boundary Interval (Halevikdere Section, Eastern Taurides), Eberhard Schindler, Reimund Haude, Mehmet Namik Yalçin, Rainer Brocke, Ati̇ke Nazi̇k, Emine Şeker Zor, Volker Wilde, Achim Wehrmann May 2025

First Record Of Scyphocrinoids In Türkiye And Recognition Of The Silurian/Devonian Boundary Interval (Halevikdere Section, Eastern Taurides), Eberhard Schindler, Reimund Haude, Mehmet Namik Yalçin, Rainer Brocke, Ati̇ke Nazi̇k, Emine Şeker Zor, Volker Wilde, Achim Wehrmann

Turkish Journal of Earth Sciences

During the Silurian/Devonian (S/D) boundary interval, scyphocrinoids (Crinoidea, Echinodermata) flourished on a global scale. The first record of scyphocrinoids from Türkiye, especially represented by their bulbuous loboliths, is now described from the Halevikdere Section in the Eastern Taurides. The Devonian part of the section is more than 1300 m thick and covers a time span from the S/D boundary interval to the Late Devonian (Famennian). It consists mainly of fine-grained to sandy siliciclastics, event-driven conglomerates/fanglomerates and biogenic carbonates deposited in deep shelf to shallow-water coastal settings. The S/D boundary interval was measured and studied in great detail. The dominant lithology …


The Quaternary Fluvial-Lacustrine System In The Akarçay Basin (Sw Anatolia): Depositional Environments And Paleoclimatic Interpretation, Koray Aktürk, Sevi̇nç Kapan May 2025

The Quaternary Fluvial-Lacustrine System In The Akarçay Basin (Sw Anatolia): Depositional Environments And Paleoclimatic Interpretation, Koray Aktürk, Sevi̇nç Kapan

Turkish Journal of Earth Sciences

The Akarçay Closed Basin, located in southwest Anatolia, contains deformed formations and the drying Akşehir and Eber lakes. This study aimed to interpret the paleoenvironmental and paleoclimatic conditions of the Akşehir and Eber lakes, which are reported to have been connected during the Pleistocene. Based on sedimentological and mineralogical data, three different depositional subenvironments were defined, corresponding to the formation and development stages of the lake. Sedimentary facies analysis of the Pleistocene deposits in the basin revealed the following facies associations, listed from bottom to top: 1) an alluvial fan and fluvial facies association, representing the formation stage of the …


Formation Of Holocene Paleosols In A Relict Sand Dune Sequence At Kıyıköy, Türkiye, Ahmet Evren Ergi̇nal, Mustafa Bozcu, Nuretti̇n Yakupoğlu, Abdullah Akbaş, Hakan Kaya, İsmai̇l Onur Tunç May 2025

Formation Of Holocene Paleosols In A Relict Sand Dune Sequence At Kıyıköy, Türkiye, Ahmet Evren Ergi̇nal, Mustafa Bozcu, Nuretti̇n Yakupoğlu, Abdullah Akbaş, Hakan Kaya, İsmai̇l Onur Tunç

Turkish Journal of Earth Sciences

The paleoclimatic indicators from a relict dune and paleosol sequence observed south of Kıyıköy Port, NW Türkiye, provide insights into the variable paleoclimatic conditions in the western Black Sea coastal zone over the last 4700 yrs BP. The relict dune- paleosol sequence consists of reddish-brown coarse sands with abundant shells and overlying paleosol. Radiocarbon dating of Donax trunculus shells collected from the lowest part of the relict dune revealed the onset of sand deposition 4689 ± 123 yrs ago. The dark-colored paleosol layer, with an Rb/Sr ratio of 0.008, yielded an age of 287 ± 32 yrs cal BP. These …


U-Pb Calcite Geochronology, Epr, Geochemistry, And C-O-Sr Isotopes Of Africanomarbles In The Seferihisar (İzmir, Türkiye) U-Pb Calcite Geochronology, Epr, Geochemistry, And C-O-Sr Isotopes Of Africano Marbles In The Seferihisar (İzmir, Türkiye), Fatma Şi̇şman Tükel, Namik Aysal, İpek Deni̇z Yildirim, Marcel Guillong, Tonguç Uysal, Si̇nan Öngen, Emre Erdem May 2025

U-Pb Calcite Geochronology, Epr, Geochemistry, And C-O-Sr Isotopes Of Africanomarbles In The Seferihisar (İzmir, Türkiye) U-Pb Calcite Geochronology, Epr, Geochemistry, And C-O-Sr Isotopes Of Africano Marbles In The Seferihisar (İzmir, Türkiye), Fatma Şi̇şman Tükel, Namik Aysal, İpek Deni̇z Yildirim, Marcel Guillong, Tonguç Uysal, Si̇nan Öngen, Emre Erdem

Turkish Journal of Earth Sciences

The Africano marbles (Africano Verde and Bigio Africano) extracted from the region of Sığacık (ancient Teos) region and its surroundings were widely used and even traded in construction and decorative items throughout the Roman period due to their brecciated and colourful appearance. There are two different types of Africano marble, the first consisting of marble breccias embedded in a dark matrix. In this type, the marble breccias show micritic, microsparitic, and sometimes sparitic textures formed by coarse-grained calcite, while the dark matrix consists of chlorite and/or serpentine minerals. The second type is Bigio Africano, which consists of grey-blue homogeneous limestones, …


Math 115: College Algebra Instructor Guide, Seth Lehman May 2025

Math 115: College Algebra Instructor Guide, Seth Lehman

Open Educational Resources

OER instructor guide for Math 115, College Algebra, Queens College


Wildlife Road Mortalities During Covid-19 Pandemic-Related Lockdown In South Texas: A Comparative Survey, Bradley Evan Beer, Kevin W. Ryer, Md Saydur Rahman, John H. Young Jr., Richard J. Kline May 2025

Wildlife Road Mortalities During Covid-19 Pandemic-Related Lockdown In South Texas: A Comparative Survey, Bradley Evan Beer, Kevin W. Ryer, Md Saydur Rahman, John H. Young Jr., Richard J. Kline

School of Earth, Environmental, & Marine Sciences Faculty Publications

Mortalities of wildlife caused by collisions with vehicles along roads are increasing in prevalence, threatening the existence of various species and populations. The COVID-19 pandemic-related lockdown provided an opportunity to gain a better understanding of how wildlife vehicle mortality occurrences change in response to anthropogenic variables and how varying survey methods influence obtaining mortality data. In this study, data were collected in three observation periods: pre-lockdown (PreL), during lockdown (DL), and post-lockdown (PostL) in south Texas. There were 194 wildlife mortalities recorded during weeks 4–27 of 2020. Results of this study showed that road mortality survey counts did not change …


Calculating Moment Magnitude Using The Coda Calibration Technique To Update The Earthquake Catalog Of Iraq (1900-2021), Muntadher Al-Kaabi May 2025

Calculating Moment Magnitude Using The Coda Calibration Technique To Update The Earthquake Catalog Of Iraq (1900-2021), Muntadher Al-Kaabi

Theses and Dissertations

The first comprehensive earthquake catalog for Iraq based on moment magnitude (Mw) ‎was compiled by Onur et al. (2017). It spanned the period from 1900 until the end of ‎‎2009, covered the region between 26°–40° N latitudes and 36°–51° E longitudes, and ‎included more than 18,000 earthquakes, of which roughly 4,000 are of Mw 4.0 or larger. ‎With the ongoing efforts of updating the probabilistic seismic hazard assessment ‎‎(PSHA) and the Iraqi building code, the need for an updated earthquake catalog for Iraq ‎in terms of moment magnitude (Mw) has been raised. Robust estimation of moment ‎magnitude (Mw) can be …


Mechanisms And Collaborative Prevention And Control Techniques For Various Disasters In Coal Seam Roofs, Zheng Kaige, Zhang Jian, Sun Siqing, Chen Dongdong, Wang Zeyang May 2025

Mechanisms And Collaborative Prevention And Control Techniques For Various Disasters In Coal Seam Roofs, Zheng Kaige, Zhang Jian, Sun Siqing, Chen Dongdong, Wang Zeyang

Coal Geology & Exploration

Objective The multistage sedimentary and tectonic evolution of coal seams in China has led to the formation of environments with the coexistence of multiple disasters including gas outbursts, water inrushes, and rock bursts. To address the chain evolution of these disasters induced by the coupling of high in situ stress, high water pressure, and intense mining under the condition of deep coal mining, this study systematically investigated the coupling mechanisms and collaborative prevention and control techniques of multiple dynamic disasters in coal seam roofs. Methods Based on the regional tectonic characteristics and the delineation of coal-bearing tectonic units, this study …


Mechanisms And Equation Improvement For Gas Seepage In Coal Seams Around Boreholes Subjected To High-Pressure Co2 Foam Fracturing, Pang Mingkun, Zhang Tianyu, Pan Hongyu, Song Xianfeng, Wu Shan, Zhang Tianjun May 2025

Mechanisms And Equation Improvement For Gas Seepage In Coal Seams Around Boreholes Subjected To High-Pressure Co2 Foam Fracturing, Pang Mingkun, Zhang Tianyu, Pan Hongyu, Song Xianfeng, Wu Shan, Zhang Tianjun

Coal Geology & Exploration

Objective The special low-porosity, low-permeability structures of high-gas-content coal seams restrict efficient gas drainage. To address this issue, this study accurately determined the seepage parameters of annularly fractured coals around boreholes subjected to CO2 foam fracturing to enhance both the design accuracy of boreholes for gas pre-drainage from coal seams and gas drainage efficiency. Methods Using an independently developed apparatus for gas seepage experiments on fractured coals around boreholes, this study investigated the coals with pores and fractures distributed in an annular pattern around boreholes from the perspective of varying initial pore structures. Specifically, this study analyzed the evolutionary …


Dominant Geological And Engineering Factors Controlling The Productivity Of Horizontal Wells For Deep Coalbed Methane In The Southern Shenfu Block, Guo Guangshan, Liu Yancheng, Zhao Gang, Chen Zhaohui, Li Chen, Kang Lifang, Wang Yuchuan, Wang Jianan May 2025

Dominant Geological And Engineering Factors Controlling The Productivity Of Horizontal Wells For Deep Coalbed Methane In The Southern Shenfu Block, Guo Guangshan, Liu Yancheng, Zhao Gang, Chen Zhaohui, Li Chen, Kang Lifang, Wang Yuchuan, Wang Jianan

Coal Geology & Exploration

Objective The southern Shenfu block along the eastern margin of the Ordos Basin hosts one of the rare gas fields with reserves of over 100 billion cubic meters (bcm) in China, serving as a pilot demonstration area for the exploration and production of deep coalbed methane (CBM) conducted by the China National Offshore Oil Corporation (CNOOC). In this block, the gas production of horizontal wells is 2-10 times that of vertical wells. However, the horizontal wells are challenged by significantly different and rapidly declining gas production. Determining dominant factors controlling the productivity of horizontal wells for deep CBM is the …


Impacts Of The Hydrochemical Characteristics Of Coal Seam Water On The Structures And Metabolic Functions Of Microbial Communities, Wang Gaohao, Duan Shengjie, Wang Bei, Niu Guobin, Liang Yongping, Yu Feilong, Ma Kai, Zhao Weizhong May 2025

Impacts Of The Hydrochemical Characteristics Of Coal Seam Water On The Structures And Metabolic Functions Of Microbial Communities, Wang Gaohao, Duan Shengjie, Wang Bei, Niu Guobin, Liang Yongping, Yu Feilong, Ma Kai, Zhao Weizhong

Coal Geology & Exploration

Background The core of coalbed methane (CBM) bioengineering is to inject bio-fracturing fluids rich in efficient methanogenic bacteria into coal reservoirs to promote the conversion of coals to methane. However, the relationships of the hydrochemical characteristics of coal seam water with the structures and metabolic functions of microbial communities remain unclear. Methods This study investigated coal seam water from 12 typical mining areas in Ningxia. Based on microbial classification and sequencing, as well as statistical analysis, this study explored the relationships of pH, anions, cations, and chemical oxygen demand (COD) of coal seam water with the structures and metabolic functions …


Construction And Application Of A Model For Drainage Via Directional Boreholes Against Water Hazards In Deep Vertical Shafts, Zhao Chunhu, Zhu Mingcheng, Ji Yadong, Wang Shidong, Zhang Wenzhong, Zhu Kaipeng, Liu Yingfeng, Shang Hongbo, Li Chaofeng, Fan Min, Li Kai May 2025

Construction And Application Of A Model For Drainage Via Directional Boreholes Against Water Hazards In Deep Vertical Shafts, Zhao Chunhu, Zhu Mingcheng, Ji Yadong, Wang Shidong, Zhang Wenzhong, Zhu Kaipeng, Liu Yingfeng, Shang Hongbo, Li Chaofeng, Fan Min, Li Kai

Coal Geology & Exploration

Background Vertical shafts are typically employed in the deep mining areas of Jurassic coalfields in western China. However, the direct exposure of extremely thick Cretaceous aquifers frequently leads to significant water inflow in shafts. Meanwhile, the continuous sand-carrying water inflow and scouring in vertical shafts pose serious safety hazards to the overall quality of shaft walls. Methods In underground water exploration and discharge boreholes, water outlets are below the floors of aquifers to be drained. This allows unpowered water discharge. In other words, water can flow out naturally. By fully leveraging this advantage, combined with the favorable condition of spatial …


Diffusion Mechanisms Of Power-Law Grouts In Water-Rich Sand Layers During Permeation Grouting, Xie Bao, Cheng Hua, Wang Xuesong, Li Mingjing, Liu Xiangyang, Han Xueyu May 2025

Diffusion Mechanisms Of Power-Law Grouts In Water-Rich Sand Layers During Permeation Grouting, Xie Bao, Cheng Hua, Wang Xuesong, Li Mingjing, Liu Xiangyang, Han Xueyu

Coal Geology & Exploration

Objective This study aims to clarify the spherical diffusion patterns of power-law grouts in water-rich sand layers during permeation grouting and their influential factors. To this end, permeation grouting experiments were conducted to gain insights into the quantitative impacts of varying grouting parameters on grout diffusion.Methods Using model experiments on spherical diffusion during permeation grouting, this study analyzed the macroscopic diffusion morphologies and microscopic infilling effects of grouts, as well as the trends of permeation and soil pressures during grouting. Then, based on the spherical diffusion equations for permeation grouting that consider multi-effect coupling, this study analyzed the factors …


A Phase Transition-Induced Fracturing Permeability Enhancement Technology Using Carbon Dioxide Capsules For Low-Permeability Coal Seams And Its Application, Li Mao, Fan Xinchuan, Fu Hui May 2025

A Phase Transition-Induced Fracturing Permeability Enhancement Technology Using Carbon Dioxide Capsules For Low-Permeability Coal Seams And Its Application, Li Mao, Fan Xinchuan, Fu Hui

Coal Geology & Exploration

Objective and Methods To address engineering challenges like high gas content, high pressure, and low drainage efficiency in the mining of low-permeability coal seams, this study developed a phase transition-induced fracturing and permeability enhancement technology using carbon dioxide (CO2) capsules for low-permeability coal seams. This technology leverages the feature that CO2 transitions into the supercritical state under high pressure. A capsule encapsulating critical CO2 is placed into a conduit, which is then placed within a coal seam. Subsequently, phase transition-induced blasting is triggered using a heating blasting start device. Consequently, liquid CO2 vaporizes rapidly and …


Assessing The Potential And Suitability Of Geothermal Resources Using Monte Carlo Simulation And Game-Based Combination Weighting Method, He Yixiang, Ding Pengpeng, Liu Shaohua, Wang Mingzhu, Zhu Lei May 2025

Assessing The Potential And Suitability Of Geothermal Resources Using Monte Carlo Simulation And Game-Based Combination Weighting Method, He Yixiang, Ding Pengpeng, Liu Shaohua, Wang Mingzhu, Zhu Lei

Coal Geology & Exploration

Background Geothermal energy in porous sandstone reservoirs is recognized as stable, efficient clean energy. However, these reservoirs feature heterogeneity and exploration uncertainty, posing serious challenges to probabilistic resource assessment and the identification of suitability for resource development.Methods This study investigated the geothermal resources in the Guantao Formation within the northwest Shandong plain. Using the volumetric method and Monte Carlo simulation, this study assessed the uncertainty of the resource potential. Then, considering the characteristics of geothermal resources, the attributes of geological structures, and the social economy, this study developed a multi-dimensional evaluation index system for the suitability of sandstone geothermal …