Digital Commons Network^™

Experimental Investigation On Hydrogen-Rich Syngas Production Via Gasification Of Common Wood Pellet In Bangladesh: Optimization, Mathematical Modeling, And Techno-Econo-Environmental Feasibility Studies, Md Sanowar Hossain, Mujahidul Islam Riad, Showmitro Bhowmik, Barun K. Das

Research outputs 2022 to 2026

Since hydrogen produces no emissions, there is increasing interest in its production throughout the world as the need for clean and sustainable energy grows. Bangladesh has an abundance of biomass, particularly wood pellets, which presents a huge opportunity for gasification to produce hydrogen. Gasification of mahogany (Swietenia mahagoni-SM) and mango (Mangifera indica-MI) wood is performed in a downdraft gasifier to evaluate the impact of particle size, equivalence ratio, and temperature on hydrogen gas composition and gasifier performance. Under the optimal conditions determined by central composite design-response surface methodology (CCD-RSM) optimization, gasification of SM and MI wood can greatly increase hydrogen …

A Pollutant’S Tale: An Interactive Talk On The Chemistry Of The Earth’S Climate And Its Response To Pollutants, Timothy G. Harrison, Michael T. Davies-Coleman, Alison C. Rivett, M. Anwar H. Khan, Joyce D. Sewry, Magdalena Wajrak, Nicholas M. Barker, Jonny Furze, Sophie D. Franklin, Linda Sellou, Naomi K.R. Shallcross, Dudley E. Shallcross

Research outputs 2022 to 2026

A Pollutant’s Tale and its primary school version, Gases in the Air, are two talks that have been developed and modified over the last ca. 18 years, that provide audiences from approximately 4-90 years old with the background to the composition of the Earth’s lower atmosphere, the Earth’s climate, and the impact of air pollution. In this article, we describe the content of the talks and provide videos of each experiment individually as well as a recorded performance of both talks to an empty auditorium. In this article, we discuss ways that the talk can be further developed and its …

Growth, Survival, And Herbivore Browsing Preferences Of Seedlings Planted In Black Ash Stands Of Northern Michigan And Wisconsin, Seth W. Davenport

Dissertations, Master's Theses and Master's Reports

To mitigate the cascading ecosystem impacts of widespread black ash (Fraxinus nigra) mortality due to the invasive emerald ash borer (Agrilus planipennis), forested wetlands can be underplanted with seedlings of alternative species that later repopulate the vacated canopy. This study examined the survival and growth, factors influencing performance, and herbivore browsing preferences of seven non-ash species planted in northern Michigan and Wisconsin. The best performing species were river birch (Betula nigra), silver maple (Acer saccharinum), and swamp white oak (Quercus bicolor). The worst performing species was black spruce (Picea …

Dam It All: A Multi-Scalar Investigation Into The Ecological Role And Function Of Beaver Dams, Kenneth Larsen

Dissertations, Master's Theses and Master's Reports

The central theme of this dissertation is ecological scaling, which examines how small, localized features, such as beaver ponds, contribute to large-scale watershed processes and how different modeling approaches at various scales reveal distinct insights. Through a combination of probabilistic modeling and high-resolution empirical research, this work demonstrates that small ponded systems, particularly those created by beavers (Castor canadensis), serve as critical biogeochemical control points, whose contributions to sediment and nutrient dynamics have been historically underestimated.

In Chapter 1, I contextualize this research within the broader fields of freshwater ecology, watershed modeling, and ecological restoration. I introduce the …

Ecological Resources Of A Heavily Modified And Utilised Temperate Coastal Embayment: Cockburn Sound, Peter J. Mitchell, Daniel E. Yeoh, Kurt N. Krispyn, Claire N. Greenwell, Sorcha Cronin-O’Reilly, Delphine B.H. Chabanne, Glenn A. Hyndes, Danielle Johnston, David V. Fairclough, Claire Wellington, Alan Cottingham, Gary Jackson, Jeffrey V. Norriss, Matias Braccini, Hector Lozano-Montes, Chandra P. Salgado Kent, Erin Clitheroe, Alissa Tate, James W. Penn, Marion Massam, Neil R. Loneragan, James R. Tweedley

Research outputs 2022 to 2026

Coastal environments and their associated biota provide numerous environmental, economic and societal services. Cockburn Sound, a temperate embayment on the lower west coast of Western Australia, is immensely important for the State and adjacent capital city of Perth. However, urbanisation and associated terrestrial and marine development has the potential to threaten this important ecosystem. This study collated published and unpublished data to review the current state of the ecological resources of Cockburn Sound and describe how they have changed over the past century. Post-WWII, the embayment began undergoing pronounced anthropogenic changes that limited oceanic water exchange, increased nutrient load, modified …

Natural Hydrogen Soil Gas Emissions Near Harvey, Perth Basin: A Comparative Study Of Survey Methods, Krista Davies, Peter W. Haines, Charmaine Thomas, Leon Normore

Research outputs 2022 to 2026

Quantifying natural hydrogen soil gas emissions and their controlling factors is critical for assessing hydrogen storage viability and improving exploration strategies. This study provides the first detailed comparison of hydrogen emissions near the DMP Harvey-2 well in the Perth Basin and compares the effectiveness of repeated point surveys and autonomous monitoring in capturing emission variability. Hydrogen concentrations ranged from 0 to >1000 ppm in point surveys, with transient pulses up to 598 ppm detected through continuous monitoring, indicating episodic release. Repeated point surveys successfully captured the overall range of emissions but failed to resolve dynamic processes, such as abrupt flux …

Developing A Roadmap For Green Port In Timor-Leste, Emanuel Da Silva Maia

World Maritime University Dissertations

No abstract provided.

Catalyzing Meteorological Insights With A Cost-Effective Weather Monitoring System, Ariful Alam, Sidratula Muntaha, Poonam Munshi, Israt Khan, Rakibul Islam, Jamil Bhuian, Md.Yasir Arafat, Md. Ridwanul Hasan

Journal of Environmental Science and Sustainable Development

Undoubtedly, one of the biggest alarming phenomena of this decade is the tremendous fluctuations in the weather and climate. Therefore, different types of surveys, investigations, and research are required in this regard in every region. A low-cost weather monitoring system can be implemented in every educational and research institute to collect and analyze different types of weather-related data. This study establishes the method of developing such a system and analyzing data in a simplified way which the data gathered during thunderstorms and cyclonic activity in Bangladesh. The system was designed with Proteus 8 professional software and developed by using a …

Impact Of Urban Development On Uv Exposure: A Clustering And Machine Learning Assessment, Taufik Roni Sahroni Mr., Verdi Yasin, Lulut Alfaris, Reza Ariefka, Ruben Cornelius Siagian, Mohammad Alfin Karim, Nana Rahdiana, Ade Suhara

Journal of Environmental Science and Sustainable Development

The relocation of Indonesia's capital city is anticipated to promote inclusive economic growth while embracing cultural diversity. However, this transition may affect ultraviolet (UV) radiation exposure patterns. The study investigated variations in UV exposure in the IKN region, focusing on urban development factors such as land use and population density that affect public health, sun protection, and skin cancer prevention. The research hypothesized that UV radiation is significantly correlated with these factors. UV Index data from 2010-2023, a hierarchical clustering method, identifies complex data patterns without determining the number of clusters. XGBoost, a machine learning model, was used for handling …

Multi-Sensor Data Fusion And Gis-Drastic Integration For Groundwater Vulnerability Assessment With Rainfall Consideration, Wu Jiazhe, Dai Xinrui, Su Yangcheng, Zheng Xiangtian, Bushra Ghaffar, Rabiya Nasir, Ahsan Jamil, Zeeshan Zafar, Mohammad Suhail Meer, M. Abdullah-Al-Wadud, Rahila Naseer, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

In many areas of the world, particularly in arid and semi-arid regions, groundwater is the primary source of fresh water, and it supplies around one-third of the world's fresh water. Agriculture is the primary economic sector on the coast in the southern district (Nowshera). More food productivity is required due to the expanding population and diminishing agricultural lands, which increases the use of chemical pesticides and fertilizers in farming. The current study was conducted in northwestern parts of Pakistan to evaluate the impacts of the frequent use of pesticides and fertilizers in agricultural fields. Nine hydrogeological parameters were considered, and …

Unfolding Cascading Impacts Of Changing South Asia Monsoon On A Hindu Kush Himalayas Basin, Surendra Maharjan, Wenzhao Li, Shahryar Fazli, Arshad Ansari, Suraj Tiwari, Roma Thakurathi, Rejoice Thomas, Hesham El-Askary

Mathematics, Physics, and Computer Science Faculty Articles and Research

Study region

Study focus

New hydrological insights for the region

Potential Health Risks From Trace Elements In Four Commercially Important Fish Species From The Gulf Of Alaska And Bering Sea Excel Data Sheet, Miranda Brohman, Dimtirios Giarikos, Amy Hirons

SECLER Data

Alaskan waters support a diverse array of fish species that are critical to apex predators and substantial commercial fisheries. Archived white lateral muscle tissue for capelin, herring, walleye pollock, and Pacific cod, from 1993 to 1996 were analyzed for 15 trace elements using induced coupled plasma mass spectrometry. This analysis serves as a proxy for assessing trace element concentrations in the Gulf of Alaska and Bering Sea. The highest concentrations of eight of the 15 elements (cadmium, chromium, cobalt, iron, manganese, selenium, vanadium, and zinc) were found in fish from the central Gulf of Alaska, while capelin showed the …

Coal Gasification Through Microbial Degradation In A Low-Pressure Co2 And H2 Environment: An Experimental Study, Jian Kuo, Fu Xuehai, Liu Mingjie, Liu Jian, Li Jin, Ru Zhongliang, Ji Xiaofeng, Wang Qiang

Coal Geology & Exploration

Objective and Methods This study aims to investigate the characteristics of CO₂ biomethanation and coal gasification through microbial degradation in a low-pressure environment. With low-rank bituminous coals (R_max = 0.67%) as fermentable substrates, this study conducted a 96-day gas production experiment through microbial fermentation in a low-pressure CO₂ and H₂ environment. Using techniques including gas chromatography, 16S rRNA gene sequencing, and low-temperature liquid nitrogen adsorption, this study delved into the intrinsic variation patterns of biogenic gas production, microbial communities, and coal structures. Results and Conclusions The results indicate that compared to conventional fermentation, the injection …

Predicted Water Yield Of Open-Pit Metal Mines Based On A Bi-Rnn And Gms Coupling Model, Zhao Yuxing, Li Xiangwen

Coal Geology & Exploration

Objective Accurately predicting water yield of mine before mining can provide directive guidance for preventing potential water hazards and ensuring safe production. Methods To enhance the prediction accuracy and stability of water yield of open-pit metal mines, for which atmospheric precipitation acts as the primary recharge source of water, this study developed a prediction model that coupled a bidirectional recurrent neural network (Bi-RNN) and the Groundwater Modeling System (GMS) software. Specifically, based on historical forecasted precipitation data provided by the Global Forecast System (GFS), the fluctuation pattern of differences between predicted forecasted and actual precipitation was analyzed. After being corrected …

An Experimental Study Of The Application Of The Spectral Acoustic Method To The Advance Detection Of Geologic Structures In Tunnelling Working Site, Zhang Jianguo, Feng Zhicheng, Wei Fengqing, Ma Ji, Zhao Kai, Wang Man, Guo Minggong, Шилов Владимир Иванович

Coal Geology & Exploration

Objective The practice of coal mine production has proved that the vast majority of coal and gas outbursts are controlled by geological structures, and mainly occur in tunnelling working site. Therefore, continuous advanced detection of geological structures is an important technical means to prevent and control coal and gas outbursts in tunnelling working site, and is of great significance to ensure safe production in mines. Methods Based on the research results of spectral acoustic method in Russia for many years, the resonance phenomenon generated at the weakened contact surface of the roof rock layer by the artificial acoustic signal excited …

Application Of Microseismic Monitoring In The Optimization Of Control Strategy For Roofs Composed Of Composite Hard Sandstone Masses, Zhang Yin, Li Jiajun, Zhao Qian, Yang Chenchen, Liu Jiaqi, Zhou Yu

Coal Geology & Exploration

Objective With a gradual increase in the coal mining depth in China, the movement of overlying thick and hard rock layers exerts increasingly complex impacts on the mine pressure. Methods In the Ordos area, the overburden of the mining face of most mines hosts composite hard sandstone masses, serving as key layers characterized by considerable thicknesses, high hardness, and close proximity. Results and Conclusions As a result, the risks of mine earthquakes and dynamic manifestation co-exist in the mining face. With the roof of mining face11-3106 in a coal mine within the Ordos mining area as the engineering background, this …

A Dc-Unet-Based Image Processing Method For Detecting Fractures Along Roadway Sections Of Coal Mines, Dong Zheng, Zhang Xuhui, Yang Wenjuan, Kang Le, Tang Duwei, Tian Chenhui

Coal Geology & Exploration

Objective Detecting fractures along roadway sections of coal mines allows for the characterization of the geologic conditions of roadways, thus providing guidance for roadway tunneling and support engineering. However, conventional image processing methods for fractures along roadway sections are susceptible to complex environments in underground coal mines, exhibiting a low fracture detection efficiency. Methods This study proposed a novel image processing method for detecting fractures along roadway sections based on a DC-UNet model. This method can be deployed on a mobile terminal and an embedded device, thereby allowing for real-time and effective detection of fractures along roadway sections and enhancing …

Development Of A Power Recovery-Based Dynamic Loading System For Full-Size Drill Rods In Coal Mines, Zhang Jing, Wang Jie

Coal Geology & Exploration

Objective This study aims to simulate the actual forces applied to drill rods during the borehole drilling for gas drainage from underground coal mines to satisfy the requirements of drill rods’ fatigue tests. Methods This study designed a dynamic loading system for full-size drill rods in coal mines. This system consists of a drill rod loading platform, a hydraulic pump unit with power recovery, and a measurement and control system, allowing for the composite loading of dynamic torque, axial force, and radial displacement on drill rods of different specifications. In this system, torque is loaded to drill rods using the …

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

Failure Depths Of Stope Floors Under Dynamic Loading Induced By Roof Breaking, Huang Qisong, Xu Bo, Feng Junjun, Lin Xiaofei, Cheng Jiulong, Peng Jun

Coal Geology & Exploration

Objective Accurately assessing the failure depths of stope floors is crucial for assessing floor water inrush risks. Conventional theoretical models for calculating the failure depths generally merely consider static loads from the support pressure and confined water's pressure in stopes, leading to large deviations between calculation results and actual situations. Therefore, constructing a more practical computational model that comprehensively considers the coupled effects of multiple force sources on the failure of deep floors can provide a scientific basis for the effective prevention and control of water hazards in deep coal seam floors. Methods Based on the dynamic elasticity theory and …

Construction And Correction Of A 3d Digital Twin For A Complex Gangue-Bearing Coal Seam, Zhang Meichen, Zhao Lijuan, Wang Yadong, Zhang Kai

Coal Geology & Exploration

Objective 3D digital twin for complex gangue-bearing coal seams are designed to achieve an information-based description of physical coal seams and faithfully map their virtual forms. digital twin is identified as a prerequisite for exploring the efficient cutting of intelligent shearers while providing an effective data guarantee for achieving unmanned mining. Methods Using data on samples from the mining face of coal seam 17 in the Yankuang Energy Group Co., Ltd. Shandong Province, this study proposed a methodology that integrates more information about the geological structural conditions of coal seams. Specifically, digital twining of iron sulfide nodules was performed using …

Influence Mechanisms Of Dynamic Metamorphism On The Evolution Of Micro/Nano Pore Structures In Tectonically Deformed Coals, Liu Hewu, Lyu Xiaoxue, Hou Chenliang, Xiong Zuopeng

Coal Geology & Exploration

Objective Micro/nano pore structures in coals act as a significant space for gas occurrence. Exploring the evolutionary mechanisms of micro/nano pore structures in tectonically deformed coals (TDCs) under the influence of dynamic metamorphism assists in gaining a deep understanding of the mechanisms underlying coal and gas outbursts. Methods Using CO₂ adsorption experiments, Fourier transform infrared (FTIR) spectroscopy, and molecular dynamics simulations, this study investigated the evolutionary characteristics and mechanisms of micro/nano pore structures in different TDCs occurring within the No.72 coal seam of the Qi’nan Coal Mine in Suzhou Province. Results and Conclusions The results indicate that with enhanced …

Mechanisms And Influential Factors Of Rock Bursts In Tunneling Roadways Of Extra-Thick Coal Seams, Peng Yujie, Wang Qiang, Cao Anye, Xue Chengchun, Lyu Guowei, Hao Qi, Liu Yaoqi, Bai Xianxi, Li Dong

Coal Geology & Exploration

Objective Rock bursts occur frequently in tunneling roadways of extra-thick coal seams, significantly constraining safe coal mining. Investigating their mechanisms and influential factors is crucial to preventing and controlling such disasters in tunneling roadways of extra-thick coal seams. Methods Focusing on the tunneling roadway of mining face 250107-1 for an extra-thick coal seam within a coal mine in Gansu Province, this study established the discriminant indices for rock burst-induced roadway instability. By simulating the energy distribution patterns of surrounding rocks in the tunneling roadway using the FLAC^3D software, this study revealed the zonal energy characteristics of the surrounding rocks …

A Calculational Model For 3d Fault Complexity Based On Curvature Analysis And Fractal Dimensions, Yan Junsheng, Liu Zaibin, Fan Tao, Yang Hui, Liu Wenming, Du Wengang, An Lin, Liu Chenguang, Wang Xiaohui

Coal Geology & Exploration

Objective and Methods Faults are identified as one of the most threatening geological structural factors among hidden disaster-causing factors in coal mines. However, the 3D quantitative assessment of them remains challenging. Considering that existing quantitative indicators fail to fully reflect fault morphologies and there is a lack of 3D methods, this study proposed a calculational model for 3D fault complexity based on curvature analysis and fractal dimensions. This model improved the morphologies of traditional measurement volumes of fractal dimensions by employing the Delaunay tetrahedralization algorithm, thus effectively reducing the invalid values in calculating the 3D fractal dimensions of faults. Moreover, …

Exploration Of The Impacts Of Cement Sheath On Casing Stress Based On The Arching Effects Of Formations, An Fengchen, Miao Zhibo, Meng Siwei, Wei Ziying, Zhang Xiao, Zeng Jiaming, Wang Xiaohua

Coal Geology & Exploration

Objective With the growth in the demand for natural oil and gas and the technological progress of their production, the oil and gas well depths have been constantly setting new records. The increase in the depth corresponds to sharply increasing in-situ stress, leading to increasingly severe damage to the casing of ultradeep oil and gas wells. To enhance the bearing capacity of the casing under high in-situ stress, high-strength casing with a large wall thickness is typically employed, a measure which has been proved, however, less effective. Methods This study established a finite element model of the casing-cement sheath-formation system …

Commingling Production Of Deep Coal-Measure Gas Through Hydraulic Fracturing: Propagation Patterns Of Induced Fractures And Their Determinants, Chen Hao, Li Guozhang, Qin Yong, Wang Jianguo, Shen Jian, Sun Yuqi, Yuan Erjun, Li Dian

Coal Geology & Exploration

Objective The commingling production of coal-measure gas represents a pivotal approach to enhancing the single-well production of unconventional gas in China. However, coal-measure gas reservoirs exhibit distinctly different material compositions and physical properties, leading to uncertainty of the propagation modes and developmental degrees of fractures in different reservoirs during the hydraulic fracturing of coal-measure gas reservoirs subjected to commingling production. Therefore, effectively coordinating the stimulation of multiple reservoirs for multi-gas commingling production is crucial for minimizing production costs and maximizing production capacity. Methods This study investigated the Linxing block along the northeastern margin of the Ordos Basin as an example …

Application Of D-Insar In Monitoring The Impacts Of Shaft Grouting On Surface And Building Deformations, Liu Hui, Lu Rumeng, Su Lijuan, Cheng Shiguang, Zhang Pengfei, Cheng Hua

Coal Geology & Exploration

Objective In coal mining engineering, damaged well walls pose a threat to the safety of production facilities and mines. Comprehensively monitoring the impacts of shaft grouting on the deformations of mine surface plants and surface buildings is critical for ensuring the safe production of mines. Methods This study investigated a coal mine in the mining area within northern Anhui Province. Using the 15 scenes of Sentinel-1A image data covering the coal mine and the differential interferometric synthetic aperture radar (D-InSAR) technology, this study comprehensively monitored the subsidence of mine surface plants and surface buildings before and after shaft grouting, obtaining …

Fracture Structure Of The Overburden In The Layered Mining Of Extremely Thick Coal Seams: Developmental Patterns Of Caving Zones And Hydraulically Conductive Fracture Zones And Fracture Characteristics, Zhang Xin, Chen Youkuo, Meng Hailun, Qin Qifa, Cheng Xianggang, Huang Rongjie, Dong Hairui, Sun Wenbin, Qiao Wei

Coal Geology & Exploration

Objective The Zhunnan Coalfield, a coalfield on the southern margin of the Junggar Basin in Xinjiang, boasts abundant coal resources. However, water hazards in mines severely constrain the safe and efficient coal production in the coalfield. Since hydraulically conductive fractures in roofs serve as primary hydraulically conductive channels formed in the mining of the mining face, it is particularly crucial to investigate the developmental patterns of these fractures during the layered mining of extremely thick coal seams. Methods This study explored the (9-15)08 mining face of the Liuhuanggou Coal Mine in Xinjiang. Using ground exploration holes and borehole televiewers, this …

Hydrochemical Characteristics And Component Sources Of Water In Underground Reservoirs In The Daliuta Coal Mine, Zhang Haitao, Jiang Binbin, Zhang Haiqin, Li Peng, Wu Min, Hao Jingwei, Hu Yutian

Coal Geology & Exploration

Objective Underground reservoirs in coal mines are capable of storing and purifying mine water. A deep understanding of the hydrochemical characteristics and formation mechanisms of water in underground reservoirs is identified as an important prerequisite for large-scale development of technologies for mine water treatment. Methods This study investigated the underground reservoirs in the Daliuta Coal Mine within the Shendong area by testing and analyzing their influent and effluent water samples. Using methods such as the ion ratio method, multivariate statistical analyses (e.g., correlation analysis and principal component analysis (PCA)), and the positive matrix factorization (PMF) model, this study delved into …

Microscopic Fracture Characterization And Permeability Evolutionary Patterns Of Granites Under Cyclic Thermal Shock, He Jiangfu, Ren Chengcheng, He Kun, Yu Qihang, Li Xinru, Deng Xu

Coal Geology & Exploration

Objective This study aims to reveal the microscopic damage characteristics and permeability evolutionary patterns of high-temperature granite reservoirs fractured under cyclic thermal shock produced by low-temperature fluids like drilling fluids and circulating heat recovery media in the exploitation process of the enhanced geothermal systems (EGSs). Methods Using experiments on the fracturing characteristics of high-temperature granites under the conditions of varying cooling methods, numbers of thermal shock cycles, and cooling temperatures, this study determined microstructural characteristic parameters such as compressional wave (P-wave) velocity, pore volumetric fraction, and fractal dimension of granites across a temperature range of 25 to 700 ℃ under …