A Preliminary Study Of Coalbed Methane Adsorption At Fractal Interfaces,
2024
School of Resources and Environment, Henan Polytechnic University, Jiaozuo 454003, China; Collaborative Innovation Center for Coal Safety Production and Clean and Efficient Utilization, Jiaozuo 454003, China; Collaborative Innovation Center of Coal Seam (Shale) Gas, Central Plains Economic Zone, Jiaozuo 454003, China
A Preliminary Study Of Coalbed Methane Adsorption At Fractal Interfaces, Jin Yi, Li Yani, Song Huibo, Zhao Mengyu, Yang Yunhang, Chen Zenan
Coal Geology & Exploration
The adsorption and desorption mechanisms of coalbed methane (CBM) are foundational for revealing CBM accumulation mechanisms and achieving efficient CBM exploitation. Studies have indicated that coal reservoirs exhibit complex pore structures with fractal features, significantly influencing CBM adsorption at pore-solid interfaces. Based on a comparative analysis of several common adsorption models for gas-solid interfaces and a summary of their characteristics and applicable conditions, this study suggests that all these adsorption models still rely on the stationary assumption of adsorption selectivity for the description and application of CBM adsorption behavior at fractal interfaces while overlooking the scale invariance of the adsorption …
Dynamic Mechanisms Of Coal And Gas Outbursts Based On A Multi-Zone Combined Coal Model,
2024
School of Emergency Management and Safety Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China
Dynamic Mechanisms Of Coal And Gas Outbursts Based On A Multi-Zone Combined Coal Model, Li Feng, Wang Chenchen, Wang Bo, Jing Yadong, Yan Zhengxu, Zhang Minbo
Coal Geology & Exploration
Coal and gas outbursts (hereafter referred to as outbursts) severely affect coal mining safety. However, many scientific problems underlying the outbursts remain unsolved. To minimize the influence of anisotropy in the mechanical properties of coals on research into outbursts, this study constructed a multi-zone combined coal model. Based on the stress distribution of overlying strata and the stress wave propagation mechanisms, this study located the weak zone of coals, shrinking the research object from the outburst center to the weak zone. Given that outbursts are triggered by the disturbance of external dynamic load, this study examined the propagation patterns of …
Evolutionary Mechanisms And Models Of Strain, Porosity, And Permeability Of Compacted Broken Coals,
2024
School of Mine Safety, North China Institute of Science & Technology, Beijing 101601, China
Evolutionary Mechanisms And Models Of Strain, Porosity, And Permeability Of Compacted Broken Coals, Li Lei, Lu Shouqing, Chu Tingxiang, Zhong Xiaoxing, Liu Chongyang, Ren Ting
Coal Geology & Exploration
Residual coal areas in caving zones of goaves in coal mines serve as primary sites for low-temperature reactions between coal and oxygen. Hence, exploring the evolutionary models of the strain, porosity, and permeability of coals in these areas holds great significance for gaining a deep understanding of the spontaneous combustion process and regularity of coals. Based on the self-developed experimental device for gas seepage in compacted broken coals, this study explored the evolutionary patterns of the strain, porosity, and permeability of compacted coals with single/mixed particle sizes during gas seepage. Furthermore, this study analyzed the variations in the strain, porosity, …
Botdr-Based Horizontal Deformation Monitoring Of Section Coal Pillars,
2024
College of Energy Engineering, Xi’an University of Science and Technology, Xi’an 710054, China; Key Laboratory of Western Mine Exploitation and Hazard Prevention, Ministry of Education, Xi’an 710054, China
Botdr-Based Horizontal Deformation Monitoring Of Section Coal Pillars, Chai Jing, Hao Hongru, Yang Jianfeng, Gao Dengyan, Gao Kuiying, Chen Jianhua, Yang Lei, Liu Zeyu
Coal Geology & Exploration
To address potential safety hazards like microcrack initiation, deformation, and failure inside coal pillars, this study monitored the horizontal deformations of coal pillars using the Brillouin optical time-domain reflectometry (BOTDR)—a distributed optical fiber sensing technology. Firstly, this study established a method for converting the axial strain of optical fibers into horizontal deformations based on a theoretical analysis of the failure and bulking characteristics of coal pillars. Secondly, it determined the axial tensile response of metal-based cord-shaped sensing optical fibers by conducting laboratory tests. Then, it corrected the strain coefficient based on the deformation and failure patterns of coal pillars. Finally, …
Carbon Microspheres In Natural Coke: Optical Microscopic Characteristics And Their Origin And Implications,
2024
School of Resources and Environment Engineering, Anhui University, Hefei 230601, China
Carbon Microspheres In Natural Coke: Optical Microscopic Characteristics And Their Origin And Implications, An Yanfei, Chen Kaixin, Wang Yaqiao, Cheng Shuo, Huang Jian, He Shuyang, Wang Shengjian
Coal Geology & Exploration
Carbon microspheres (CMs) in natural coke are formed when coal seams undergo magma-induced rapid thermal metamorphism. Analyzing the origin of the optical microscopic characteristics of CMs assists in gaining deep insights into the rapid thermal carbonization and metamorphism of coals. This study examined the natural coke samples rich in CMs from Shitai Coal Mine in Huaibei, Anhui Province. Using experiments like high-resolution reflected polarized light microscopy and scanning electron microscopy (SEM), this study characterized the particle sizes, distribution, optical microscopic characteristics, and ultramicrofabrics of CMs in natural coke, revealing the origin and thermal evolution implications of their optical anisotropy. The …
Technologies For Water Hazard Prevention And Control In Burnt Rock Aquifers Within Concealed Burnt Areas,
2024
CCTEG Xi’an Research Institute (Group) Co., Ltd., Xi’an 710077, China; School of Resources and Geociences, China University of Mining and Technology, Xuzhou 221116, China
Technologies For Water Hazard Prevention And Control In Burnt Rock Aquifers Within Concealed Burnt Areas, Wang Hai
Coal Geology & Exploration
Burnt rocks are extensively distributed in northwestern China, featuring well-developed pores and fractures and abundant water, emerging as primary aquifers in this region. The burnt rocks in concealed burnt areas in this region show inconspicuous surface remains, complicating their identification. Penetrating burnt rock aquifers in coal mining will lead to water hazard and destroy water resources in these aquifers. To prevent and control water hazard in burnt rocks within concealed burnt areas and preserve water resources in burnt rock aquifers, this study analyzed the distributions of burnt rocks in China and the effects of water in them on coal mining. …
Water Inrush Mechanism And Water-Conducting Fractured Zone’ Developmental Patterns Of A Typical Ultra-Thick Coal Seam In The Huanglong Coalfield During Fully Mechanized Mining,
2024
School of Resources and Geosciences, China University of Mining and Technology, Xuzhou 221116, China; Shaanxi 194 Coal Geological Co., Ltd., Tongchuan 727000, China
Water Inrush Mechanism And Water-Conducting Fractured Zone’ Developmental Patterns Of A Typical Ultra-Thick Coal Seam In The Huanglong Coalfield During Fully Mechanized Mining, Yan Heping, Li Wenping, Duan Zhonghui, Yang Yugui
Coal Geology & Exploration
The mining of thick coal seams in the Huanglong Jurassic coalfield has led to the formation of high water-conducting fractured zones, which are prone to connect the extremely thick sandstone aquifers of the overlying Cretaceous Luohe Formation. Qinggangping Coal Mine in the coalfield exhibits the typical characteristics of pulsed water inrushes during coal mining, posing a severe threat to safe mining. This study investigated the fully mechanized mining face 42105 in Qinggangping Coal Mine. Using 3DEC discrete element simulation, flushing fluid leakage in boreholes, integrated geophysical exploration, and borehole TV, this study examined the developmental patterns of the water-conducting fractured …
Research On Digital Twin-Driven Tracking, Positioning And Collision Detection Method Of Excavating And Anchoring Equipment,
2024
College of Mechanical Engineering, Xi’an University of Science and Technology, Xi’an 710054, China; Shaanxi Key Laboratory of Mine Electromechanical Equipment Intelligent Detection and Control, Xi’an 710054, China
Research On Digital Twin-Driven Tracking, Positioning And Collision Detection Method Of Excavating And Anchoring Equipment, Yang Wenjuan, Zhao Dian, Zhang Xuhui, Chen Xin, Zheng Xili, Liu Yanhui, Zhang Ran, Wan Jicheng
Coal Geology & Exploration
The automation of excavating and anchoring operation is critical for intelligent excavation of coal mine roadway. Aiming at the challenges of relative pose measurement and collision detection during the alternating operation of the current excavating and anchoring equipment, a digital twin-driven tracking, positioning and collision detection method was proposed. Firstly, in order to overcome the influence of low illumination, high dust and complex background interference in the underground excavating face, the multi-point infrared LED target is taken as the information source, the infrared LED feature point image is collected by industrial camera, the center of the spot is extracted using …
Weight And Resistance Reduction Mechanism Of Drilling Rods For Drilling In Soft Coal Seam And Its Application,
2024
School of Energy Science and Engineering, Henan Polytechnic University, Jiaozuo 454003, China; State Collaborative Innovation Center of Coal Work Safety and Clean-Efficiency Utilization, Jiaozuo 454003, China
Weight And Resistance Reduction Mechanism Of Drilling Rods For Drilling In Soft Coal Seam And Its Application, Wang Yonglong, Guo Jiakuan, Yu Zaijiang, Du Kang, Sun Yuning
Coal Geology & Exploration
Gas drainage boreholes during construction is a necessary means to control gas hazards. In response to the issues such as high drilling resistance, low drilling efficiency, and high labor intensity caused by the significant self-weight of the drilling rod in drilling into the soft coal seams, a research approach of reducing the self-weight and lowering the drilling resistance by optimizing the drilling rod structure was proposed. Thus, a four-winged concave grooved drilling rod was designed to address both of its advancing resistance and rotating torque losses. Meanwhile, a drilling resistance model for the drilling rod was established. On this basis, …
Intelligent Identification Method Of Drilling Fluid Rheological Parameters Based On Machine Learning,
2024
Faculty of Engineering, China University of Geosciences, Wuhan 430074, China
Intelligent Identification Method Of Drilling Fluid Rheological Parameters Based On Machine Learning, Liu Changye, Yang Xianyu, Cai Jihua, Wang Ren, Wang Jianlong, Dai Fanfei, Guo Wanyang, Jiang Guoshe, Feng Yang
Coal Geology & Exploration
The rheology of drilling fluid, which characterizes its flow and deformation, is vital for transporting and suspending rock cuttings as well as for enhancing the drilling rate. Precise control of drilling fluid rheological parameters is essential to ensure borehole cleanliness and efficient drilling. This paper proposes an intelligent identification method for drilling fluid rheological parameters based on Convolutional Neural Networks (CNNs). The method employs magnetic stirring to generate stable images of drilling fluid flow, uses various data augmentation methods to increase the number of images and create a database, thereby enhancing the model’s robustness and generalization capabilities. The AlexNet CNN …
Synthesis Of Geopolymer Using Coal Fly Ash And Corn Stover,
2024
Louisiana Tech University
Synthesis Of Geopolymer Using Coal Fly Ash And Corn Stover, Anu Paneru
Master's Theses
The development of each nation is dependent on its infrastructure, and nations are competing with others in infrastructure, especially in the construction of roadways, since they play a vital role in the economic and social development of the nation. The conventional materials used for road construction are cement and asphalt, which pose significant environmental challenges. This thesis explores the potential of fly ash (FA) and corn stover (CS) in synthesizing geopolymer, as an alternative material for the construction of roads. The study examines the impact of FA and CS percentages and the particle sizes of CS on the compressive strength, …
Extended Producer Responsibility: Successes, Failures, And The Future Of Oregon Recycling,
2024
Portland State University
Extended Producer Responsibility: Successes, Failures, And The Future Of Oregon Recycling, Zoe Vandal
University Honors Theses
Extended Producer Responsibility (EPR) is a waste management program used globally to improve the recovery, recycling, and management of solid waste materials. There are three types of EPR programs defined by their target materials: electronic and electrical waste (WEEE) EPR, hazardous waste EPR, and packaging EPR. Europe has implemented all three types with relative success. The US has implemented WEEE EPR and hazardous waste EPR and is currently in the process of implementing packaging EPR on a state scale in Oregon, California, Colorado, Maine, and Maryland with 10 more bills being introduced in 2024 alone. Oregon's EPR program will be …
Exploring Microplastic Concentrations And The Sedimentology Of San Diego's Offshore Benthic Environments,
2024
University of San Diego
Exploring Microplastic Concentrations And The Sedimentology Of San Diego's Offshore Benthic Environments, Rachel Sarner
Theses
Marine pollution studies are showing infiltration of plastic debris in remote parts of oceans including the deep sea. Microplastics (MPs) are being discovered not only in the ocean’s water column but also benthic sediments reaching thousands of meters in depth. This is the first study to analyze MP concentrations in conjunction with sedimentary characteristics from varying deep-sea environments (coastal, deep ocean, offshore terrace) in the Southern California Continental Borderland (CCB). Our goal for this study was to observe how the concentration and type (morphology, color, size) of microplastics varied with distance from shore, with water depth, and between different submarine …
Progress And Challenges Of Sustainable Development Goals (Sdgs) In The World And In China,
2024
Key Laboratory of Regional and Urban Ecological Security, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
Progress And Challenges Of Sustainable Development Goals (Sdgs) In The World And In China, Bojie Fu, Junze Zhang
Bulletin of Chinese Academy of Sciences (Chinese Version)
Achieving the 17 Sustainable Development Goals (SDGs) adopted by United Nations is a critical task for countries around the world from 2016 to 2030. Yet, recent assessments indicate that progress on half of the SDGs has stagnated or even regressed, and that most goals are unlikely to be met by 2030. This study reviews the progress globally and in China towards achieving the 17 SDGs, and summarizes five key challenges that are impinging their realization: 1) the data gaps and insufficient monitoring capacity, 2) the high complexity of interlinkages among the SDGs, 3) the influence of regional disparities and negative …
Some Reflections On Developing Trend Of Gravimetry In China,
2024
State Key Laboratory of Geodesy and Earth's Dynamics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430077, China
College of Earth and Planetary Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
Some Reflections On Developing Trend Of Gravimetry In China, Heping Sun
Bulletin of Chinese Academy of Sciences (Chinese Version)
With the development of modern science and technology, gravimetry is growing vigorously and is increasingly becoming an interdisciplinary subject that is closely related to many others such as geology, fundamental physics, geodynamics, hydrology, oceanography, and astronomy. It is now a key subject in giving service to demands in national strategy and fundamental researches in geoscience such as fiducial surveying and mapping, resource exploration, military security, and hazard monitoring. Therefore, owning the core gravimetric techniques is one of the pivots which reflect national core competitiveness. This study first briefly overviews the history and actuality of the growth of gravimetry subject in …
Evaluating The Impact Of Wildfires On Mixed Conifer Forest Regeneration And The Effectiveness Of Usfs Management Strategies On Restoring Ecosystem Services,
2024
University of San Francisco
Evaluating The Impact Of Wildfires On Mixed Conifer Forest Regeneration And The Effectiveness Of Usfs Management Strategies On Restoring Ecosystem Services, Wyatt Farino
Master's Projects and Capstones
Wildfires are increasing in frequency, duration, and severity across Western North America. 20,438,720 acres (20.1%) of California has burned at least once since 2010. Projections suggest a statewide increase in burned area between 36% and 74% by 2085, with some forested areas in Northern California exceeding 100% in all modeled scenarios. Fire regimes have deviated far from their historical norm, significantly increasing the risk of type conversion from forest to other ecosystems. Californians rely on the myriad of ecosystem services produced by these forests to meet their basic needs. Access to these fundamental services will be severely reduced if appropriate …
Assessing The Use Of Regenerative Agriculture In California Almonds As Climate Change Resilience,
2024
University of San Francisco
Assessing The Use Of Regenerative Agriculture In California Almonds As Climate Change Resilience, Skyler M. Seamons
Master's Projects and Capstones
The agriculture sector is responsible for 10% of the United States’ greenhouse gas emissions. In turn, anthropogenic climate change threatens crops. With its Mediterranean climate, California is the country’s largest agricultural-producing state. Many California crops are at risk due to increasing temperatures and changed precipitation patterns. This paper investigates regenerative farming techniques as a tool to protect California crops from a changing climate. Almonds are used as a case study to analyze the soil management practices, finances, and policies underlying regenerative agriculture in California. A literature review and comparative analysis are used to compare regenerative and conventional soil management practices …
Elevating Urban Landscapes: How Green Roofs Enhance Biodiversity And Address Climate Change In California,
2024
University of San Francisco
Elevating Urban Landscapes: How Green Roofs Enhance Biodiversity And Address Climate Change In California, Jeffrey R. Beaudoin
Master's Projects and Capstones
Green roofs are increasingly valued for mitigating the Urban Heat Island effect, providing thermal comfort amidst rising temperatures of climate change, enhancing hydrological properties, and improving urban biodiversity. In this report, I explore the environmental benefits and practical challenges of green roofs, with a specific focus on California. My study evaluates the effectiveness of green roofs in enhancing environmental sustainability using a weighted rating system. I categorize the benefits of green roofs into key areas: thermal performance, stormwater management, ecological support, mental health benefits, noise reduction, air quality improvement, and water quality enhancement. Green roofs have shown the potential for …
Using Virtual Power Plants To Advance Decarbonization And Energy Equity In California,
2024
University of San Francisco
Using Virtual Power Plants To Advance Decarbonization And Energy Equity In California, Cheri Tsoi Yu Tse
Master's Theses
To achieve 60% renewable electricity generation by 2030 and 100% zero-carbon electricity by 2045, California must rapidly electrify and decarbonize all sectors while ensuring grid stability to avoid power outages. Virtual power plants (VPPs) are an emerging solution that can help increase the percentage of renewable energy on California’s electrical grid. This research examined how VPPs can advance decarbonization, grid stability, and energy equity in California. The report begins by clarifying the definitions and components of a VPP, finding the crucial interactions among distributed energy resources (DERs), management systems, and prosumers (energy consumers who both produce and consume electricity). Next, …
Conceptualising And Enacting Pathways To Transformative Climate Justice: Examples From The Philippines,
2024
The University of Sydney
Conceptualising And Enacting Pathways To Transformative Climate Justice: Examples From The Philippines, Justin See, Anne Shangrila Fuentes, Emma Porio, Brooke Wilmsen
Sociology & Anthropology Department Faculty Publications
Scholarship on climate change adaptation is increasingly moving from incremental responses to climate injustice towards transformative approaches that deliberately change systems to achieve just and equitable outcomes. A transformative understanding of climate justice is relatively new and evidence of how this could be achieved is in its infancy. In this paper, we conceptualise transformative climate justice as comprised of three subcomponents: (1) inclusive justice (seeking to ensure that no one, especially the most vulnerable, is left behind), (2) epistemological justice (drawing upon diverse knowledges and worldviews), and (3) restorative justice (healing and restoration of communities and the environment). We then …
