Oil, Gas, and Energy Commons^™

Test On The Strength Of The Backfill Fine Sand Mixture Composed Of Cement-Fly Ash-Cinder, Wen Liang, Yan Changhong, Zhang Zheng, Xu Baotian, Zhang Shunjing, Zhang Dongping, Zhou Yinkang

Coal Geology & Exploration

By using orthogonal test to analyze the influence of cement content, fly ash content and cinder content, the non-confining compression strength test was carried out for the stability of large-scale landfill base structure and for the saving costs. The strength at different curing ages was analyzed by variance, and the reinforcement mechanism was also studied. The test results showed that the optimal ratio of cement stabilized soil under different factors is 20% of cement, 15% of fly ash, 10% of cinder, and the strength is the largest at this point. And the influence of cement content on the strength of …

Acoustic Emission Test Of Calcareous Sands Under Undrained Condition, Yang Chao, Wang Kai, Qiao Liping, Meng Qingshan, Wang Ren

Coal Geology & Exploration

Calcareous sand acoustic emission was tested under undrained condition to study the law of acoustic emission with different confining pressure, shear rate, initial void ratio and grading. The results showed that when the confining pressure was lower than 400 kPa, calcareous sand acoustic emission event rate increased with confining pressure. But when the confining pressure was increased to 800 kPa, calcareous sand acoustic emission event rate decreased. The test of calcareous sand was divided into particle breakage stage and particle slip stage in low shear rate. Two stages can't be distinguished clearly as the shear rate increases. Loose and dense …

Random Noise Attenuation By Eemd In Common Offset Gathers, Shi Zhanzhan, Xia Yanqing, Zhou Huailai, Chi Yuelong, Pang Su

Coal Geology & Exploration

There are two problems in the random noise attenuation in f-x domain:(1) Reflected waves as hyperbolic events in pre-stack CMP gather or shot gathers, de-noising will damage the effective wave; (2) Seismic signals are complex non-stationary signals, requiring that the de-noising method has the adaptivity. Aiming at these two problems, a random noise suppression method based on f-x EEMD was proposed. The method utilizes the reflected waves which are horizontal events in common offset gathers, satisfying the f-x domain de-noising assumption, and the good adaptability of EEMD algorithm to non-stationary signals. For each frequency …

Analysis On Influence Of Ground Transmitting Electrode On Bidirectional Em-Mwd Signal Transmission Based On Ansys, Shao Chun, Han Jian, Chu Zhiwei, Xu Lin

Coal Geology & Exploration

The grounded emitter electrode is a necessary component of the bidirectional EM-MWD signal downlink system, and its reasonable parameter setting can improve the signal downlink effect, but at present, little is known about its influence on the downlink signal. This paper is based on the bi-directional EM-MWD working mechanism, combined with the current field theory, using ANSYS finite element software, establishes a three-dimensional simulation model of bidirectional EM-MWD signals, and analyzes the emission distance, length, diameter and resistivity of the ground transmitting electrode versus the downlink signal. The simulation results show that the downlink signal reception effect is positively correlated …

Elastic Wave Prestack Reverse Time Migration On Undulating Surfac, Liu Yang, Zhao Hu, Yin Cheng, Wu Sihai, Dai Ronghuo, Di Zhixin

Coal Geology & Exploration

At present, seismic exploration is facing many challenges in the "double complex" area, especially the undulating surface make it difficult to accurately image the underground complex structures. In this paper, we have studied the elastic wave prestack reverse time migration method for undulating surface, and a simple and effective treatment method was adopted to solve the free boundary conditions of undulating surface. In addition, the storage strategy of the effective boundary was used to solve the problem of big storage of elastic wave prestack reverse time migration. The numerical experimental results also show that this method can accurately reconstruct the …

Influence Mechanism Of Hard Brittle Abrasive On The Drilling Performance Of Impregnated Diamond Bit, Wang Jialiang, Wei Wenjie, Zhang Shaohe, Peng Fenfei

Coal Geology & Exploration

In order to improve the performance of diamond bit, impregnated diamond bit was prepared by adding different mass of hard brittle abrasive into matrix and drilling performance was tested by drilling experiments. The effect of hard brittle abrasive on drilling performance was studied. The results show that adding 5.5% SiC particle had better effect and the drilling efficiency increased by 55.14% compare with common bit. The hard brittle abrasive in the matrix can improving the microstructure of bit. The hard brittle abrasive left in the down hole can improve the erosion performance of washing fluid to matrix and increase the …

Finite Element 2d Forward Modeling Of Dc Method With Line Source, Xie Haijun, Li Zhiqiang, Li Sheng

Coal Geology & Exploration

In direct current prospecting, the forward calculation of 3D point source is complex and the calculation quantity is large, and using the Fourier transform can converted into 2D point source, but it is more complicated than that of 2D line source. This paper is based on Matlab programming, using the first boundary condition, and gives numerical solution of two-dimensional finite element of DC method with line source, through comparing with theoretical value of homogeneous half-space, the correctness of calculation results was verified. Then the high and low resistivity geoelectric models were built, the response of single side power supply and …

The Research Progress And Work Prospect Of Special Purpose Coal, Qiao Junwei, Ning Shuzheng, Qin Yunhu, Zhang Ning, Li Congcong, Zhang Jianqiang, Wei Yingchun, Zhu Shifei, Zhu Kaijia

Coal Geology & Exploration

Based on the refined geological exploration of coal, the clean and efficient use of coal, this paper reviews the implications of scarce coal and special purpose coal in previous studies. It was pointed out that special purpose coal is based on clean and efficient use of coal for coal resources with special industrial applications. The main types of coal are liquefaction coal, gasification purpose coal, coking coal and special high-element coal. Based on the coal quality evaluation of coal and the use of coal graded quality, this paper has sorted out the key evaluation indicators and evaluation parameters of special …

Technology And Practice For Deep Cbm Fracturing In Eastern Ordos Basin, Wang Xuxing, Wang Xingzun, Guo Bumin, Yuan Zheng, Feng Qing

Coal Geology & Exploration

The resources of deep coalbed methane buried at depth of more than 1 200 m in the eastern Ordos basin are rich and the key point for further exploration and development of CBM in the future. Compared with shallow CBM fracturing, there are many challenges in deep CBM fracturing such as with high situ stress, high closure stress, breakdown pressure as well as complex mechanical parameters of rock. Combined with the existing practice of CBM fracturing, taking the deep CBM buried at depth of about 2 000 m in the eastern Ordos basin as an example, tubing+ circulating SSD +packer …

Application Of Improved Hierarchic Analytic Process In The Classification Of Mine Hydrogeological Types, Wang Tiantian, Jin Dewu, Yang Jian, Liang Xiangyang

Coal Geology & Exploration

The classification of mine hydrogeological type is an important part of mine hydrogeology work. It is of great significance to analyze water filling conditions, evaluate water hazard and guide mine water prevention work. In order to evaluate mine hydrogeological conditions, this paper introduced optimal transfer matrix to improve hierarchic analytic process, and then applied this method to classify mine hydrogeological types. Taking four pairs of active mines in Hujierte mining area of Inner Mongolia as an example, the evaluation index system for classification of mine hydrogeological types was built on the basis of analysis of the hydrogeological conditions, then theoretical …

Design And Application Of Drilling Rod Vibration Frequency Measurement System, Liu Naipeng, Hu Yule, Wang Wei

Coal Geology & Exploration

During drilling, resonance is generated when the natural frequency of the drilling rod is consistent with the external excitation frequency. This will cause fatigue-failure of the drilling rod and serious consequences. To avoid this, a drilling rod vibration measurement system based on Micro-Electro-Mechanical System was designed. This system uses the three-axis acceleration sensor to measure the acceleration of the drilling rod in three directions. The upper computer software written in LabVIEW can storage, upload, display and process data. Then the fast Fourier Transform was taken to analyze the vibration frequency of the drilling rod. Finally the system is installed on …

Elastic Mechanics Solution Of Water Proof Key Layer In Coal Seam Floor Under High Water Pressure, Wang Yan, Yao Duoxi, Lu Haifeng

Coal Geology & Exploration

Aiming at the problem of water resisting capacity of the key layer in seam floor under the action of high pressure water, the key stratum was simplified as a fixed beam. The stress and displacement were calculated by the stress function method and the semi inverse method respectively. The results of two calculations were compared with the FLAC^3D results. The results show that the stress and displacement obtained by the stress function method are more appropriate than those calculated by the FLAC^3D method. It is suggested that for elastic mechanics analytic method of the fixed beam of the …

Integrated Identification Of Sequence Boundary Through Outcrop, Seismic With Logging And Geochemistry: A Case Of Jurassic In Northeastern Margin Of Ordos Basin, Zhang Tianfu, Zhang Yun, Cheng Yinhang, Miao Peisen, Ao Cong, Jin Ruoshi, Duan Lianfeng, Duan Xiaolong

Coal Geology & Exploration

Jurassic strata is mainly rock series containing coal and uranium in Ordos basin. The recognition of Jurassic sequence interfaces were mainly relied on the field outcrop, logging lithology of unconformity surface or the sedimentary discontinuity. However, it is tend to experience human recognition of randomness in the sequence interfaces recognition without macroscopic characteristics. Therefore, based on routine identification work such as outcrop profile and electrical curve of nearly 1 000 boreholes, combined with vertical changes of two-dimensional seismic profile and chemical index of alteration(CIA), three long-term cycle sequence interfaces(TSB1-TSB3) and seven medium-term cycle sequence interfaces(SB1-SB7) were finally identified in Jurassic …

Response Relation Between Fracturing Curve And Reservoir Pollution Degree Of Coalbed Methane Wells, Zhuang Dengdeng, Wang Yanbin, Tao Chuanqi, Chen Yan

Coal Geology & Exploration

In order to study the relationship between response curve and the pollution degree of fractured reservoir, taking Shizhuang block in Qinshui basin as an example, wells with different sensitivity of reservoir in the block were selected, through comparison of the difference of the dropping trace characteristics after the hydraulic curve reaches the fracture pressure in the fracturing curves of fracturing operation in different wells, the response law of hydraulic dropping trace and the reservoir sensitivity was summed up. Then in the same block according to the dropping trace of the hydraulic curves, the sensibility of reservoir was judged in several …

Absorber And Window Study – Cdsexte1-X/Cdte Thin Film Solar Cells, Chih-An Hsu

USF Tampa Graduate Theses and Dissertations

CdTe an II-VI semiconductor has been a leading thin film photovoltaic material due to its near ideal bandgap and high absorption coefficient [1]. The typical thin film CdTe solar cells have been of the superstrate configuration with CdS (Eg-2.42eV) as the n-type heterojunction partner. Due to the relatively narrow bandgap of CdS, a wider bandgap n-type window layer has recently emerged as a promising substitute: alloys of MgyZn1-yO have been successfully used as the emitter or window layer. The benefits in the usage of MgyZn1-yO (MZO) are its tunable bandgap and wide optical spectrum on optoelectronic devices. Due to an …

Offshore Oil Leasing: Trump Administration’S Environmentally Dangerous Energy Policy, Carol J. Miller, Bonnie B. Persons

William & Mary Environmental Law and Policy Review

The Trump administration’s Executive orders on Promoting Energy Independence and Economic Growth (“Energy Independence Order”) and Implementing an America-First Offshore Energy Strategy (“Offshore Energy Order”) set the stage to open over 90% of the continental shelf to offshore oil drilling from 2019–2024. The Offshore Energy Order ignores the statutory requirements of the Outer Continental Shelf Lands Act (“OCSLA”) and the National Environmental Policy Act (“NEPA”) to balance energy exploration with safeguards for marine life and the environment. We analyze the lack of express authority in OCSLA for the President to rescind its protective designations, in comparison to other laws that …

Molecular Dynamics Simulation On Licl-H2o Interfacial Phenomenon For Liquid Desiccant Dehumidification, Xiaohui She, Yi Chen, Yuanhao Wang, Shifeng Wang, Yimo Luo

Faculty of Science & Technology (THEi)

In this paper, molecular dynamics simulation was conducted to analyze the air-solution interface phenomenon of LiCl-H2O for liquid desiccant air dehumidification. Density profiles of ions in liquid desiccant aqueous solutions were plotted along the z axis, and distribution preferences of ions on the air-solution interface were studied. Besides, vapor pressure profiles above the solution surface were plotted, and the saturated vapor pressure was predicted and compared with the empirical data. It was found that water density remained stable in the bulk, and there was a sharp decrease on the air-solution interface. For the ions (Li+ and Cl-), a density peak …

Stable Isotopes Of Clay Minerals From Autoclave Tests Of Oil Sands: Implications For Clay Formation During Steaming Of Alberta Clearwater Oil Sands, Shaoneng He, Fred J. Longstaffe, Zhihong Zhou

Earth Sciences Publications

In an effort to evaluate mineral-water isotopic exchange during cyclic steam stimulation (CSS), solutions and<2 μm berthierine-dominated solids from the Clearwater Formation oil sands of Alberta, Canada were analyzed for stable isotope compositions before and after reaction in autoclaves for 1008 h at 250 °C. There was no significant change in solution δ¹⁸O and δ²H, which is consistent with the high water/mineral ratio used in the experiments. The solids showed a marked decrease in both δ¹⁸O and δ²H following the experiments. Pre-run solids have δ¹⁸O of +9.5 to +12.9‰and …

A Coupled Modeling Framework For Allocation Design In Land-Use And Land-Cover Changes To Optimize Biofuel Feedstock Production, Ana C. Cram

Open Access Theses & Dissertations

Environmental awareness has increased the demand for renewable energy. Notably, the production of biofuels from feedstock is gaining interest as a viable measure to reduce fossil fuels consumption. Nevertheless, it is crucial to identify the trade-offs between bioenergy crop cultivation and the environmental impact on land, water, and atmosphere.

Intensifying biofuel cultivation trigger effects associated with Land Use and Land-use-change, which are complex to assess. While hydrological models had been used to investigate the environmental impacts of land-use changes on water and soil quality, their quantitative assessment is often incomplete. Changes in land use and agricultural activities also contribute to …

Ua66/7/3 Ogden College Of Science & Engineering Chemistry Centers & Laboratories, Wku Archives

WKU Archives Collection Inventories

Records created by and about Chemistry centers and laboratories.

Fundamental Insights On The Electrolysis Of Co2 Using Solid Oxide Electrolysis Cells, Juliana Silva Alves Carneiro

Wayne State University Dissertations

The work reported in this thesis focused on providing a fundamental understanding, at the molecular level, required to guide the effective design of electrocatalysts towards a superior reaction kinetics on the electrode of solid oxide electrolysis cells SOECs devices (SOECs) during the CO2 electrolysis. High temperature SOECs are electrochemical energy conversion technologies, that have emerged as promising alternatives to mitigate environmental issues associated with combustion-based technologies, such as the rising atmospheric CO2 levels. The conversion of excess CO2 into high-energy molecules, such as CO can be efficiently achieved through the use of SOEC – which facilitates the electrochemical reduction of …

Strategies For Small Energy Consulting Business Survivability, Scholastica Nwabueze

Walden Dissertations and Doctoral Studies

Small businesses are critical to economic development. Small businesses create job opportunities and training and innovative products and services, but they encounter significant challenges and many fail in the first 7 years due to lack of sustainable strategies. The purpose of this single case study was to explore strategies owners used to sustain small energy consulting businesses for longer than 7 years. The population in this study consisted of 5 senior executives of a small energy consulting firm in the Washington, DC, metropolitan area. The conceptual framework for the study was the transformational leadership theory that deals with vision and …

Success Factors For Power Project Development Businesses In Sub-Saharan Africa, Kodjo Galevissi Afidegnon

Walden Dissertations and Doctoral Studies

Despite the financing gap in the sub-Saharan Africa power sector, private investors struggle to capitalize on the opportunity because of the high failure rate of power project development companies. Using the conceptual framework of the behavioral finance theory, this multiple case study was conducted to explore the strategies used by executives of 4 companies in sub-Saharan Africa who successfully developed power projects within the last 5 years. Data were collected from semistructured interviews and a review of government and institutions' websites. Yin's 5-phased cycle for analyzing case studies provided the guidelines for data analysis. Three themes emerged from data analysis: …

Potential Solar Consumers' Understanding Of Energy Policy Development In Hawai‘I, Kristin Li Mcgill

Walden Dissertations and Doctoral Studies

Hawai‘i has implemented renewable energy goals that assume continued investments by solar consumers who seem unaware of their role in the policy's success. Without the renewable resource generation that will come from these investments, the state will be unable to achieve its energy mandate. Using Sabatier and Jenkins-Smith's advocacy coalition framework and Ajzen's theory of planned behavior as the foundation, the purpose of this study was to better understand the perspectives of potential solar consumers on the Island of O‘ahu regarding the state's renewable portfolio standards, their level of knowledge regarding consumer impact on this policy, and their perceptions of …

Retention Strategies For Oil And Gas Industry Managers, Faye Gerard

Walden Dissertations and Doctoral Studies

The turnover cost of specialized employees in the oil and gas industry can exceed 400% of an employee's annual salary. The purpose of this multiple case study was to explore successful strategies that oil and gas company managers used to retain specialized employees. The specific population for the study was 8 managers from 4 oil and gas companies in a metropolitan city in the southern United States, which included 5 hiring managers and 3 engineering managers who had demonstrated success in retaining specialized employees. The conceptual lens used in this research study was the job embeddedness theory. Study data were …

Thermostable Phytase In Feed And Fuel Industries, Ushasree Mrudula Vasudevan, Amit Jaiswal, Shyam Krishna, Ashok Pandey

Articles

Phytase with wide ranging biochemical properties has long been utilized in a multitude of industries, even so, thermostability plays a crucial factor in choosing the right phytase in a few of the sectors. Mesophilic phytases are not considered to be a viable option in the feed industry owing to its limited stability in the required feed processing temperature. In the recent past, inclusion of thermostable phytase in fuel ethanol production from starch based raw material has been demonstrated with economic benefits. Therefore, considerable emphasis has been placed on using complementary approaches such as mining of extremophilic microbial wealth, encapsulation and …

Transmission Electron Microscopy Analysis Of Silicon-Doped Beta-Gallium Oxide Films Grown By Pulsed Laser Deposition, Cynthia Thomason Bowers

Browse all Theses and Dissertations

Due to the large band gap of β-Ga2O3 and recent improvements toward high quality native substrates and the ability to shallow dope epitaxial β-Ga2O3 it is an attractive material for applications in power electronic devices. Such devices require advances in the areas of thin film growth and carrier concentration control to deliver high mobility films appropriate for the device structures. Transmission electron microscopy (TEM) analysis can provide information concerning doping, crystal structure, and internal strain which will be valuable to assess the role of defects and impurities on the transport properties for feedback to optimize the bulk and epitaxial growth …

Energy Efficiency And Fatigue Failure On Gears And Bearings For Processing Rebar Steel, Jesus Gabriel Garcia

Open Access Theses & Dissertations

Steel industry is a major emitter of air pollutants, a leading industrial consumer of water, a minor source of contaminated liquids, a massive producer of solid waste, and a significant source of CO2. The objective on this thesis work is to minimize the greenhouse gas emissions when processing steel. Gears and bearings were evaluated based on their performance when exposed to cyclic stresses. The importance for having a proper set up on rolling mills to increase efficiency for processing rebar steel has been detailed on paper. In contrast, mechanical vibration has been measured on gears and bearings to determine efficiency …

Stratigraphic And Structural Characterization And Evolution Of Exposed Megaflaps Flanking Salt Diapirs, Cora Evelyn Gannaway Dalton

Open Access Theses & Dissertations

A Neoproterozoic salt system exposed in the Willouran Ranges of South Australia and a Mesozoic salt system in the south-central Pyrenees of Spain provide natural laboratories to investigate the stratigraphic and structural development of megaflaps flanking salt diapirs. Megaflaps are near-vertical to overturned, deep minibasin stratal panels that extend far up the flanks of steep diapirs or their equivalent welds. Megaflaps can form by halokinetic drape-folding, contraction, or a combination of these processes. The existing models of megaflap development are based primarily on seismic data, well penetrations, cross-section restorations, and numerical and analog modeling. Investigation of the sedimentology, stratigraphy, and …

A Study Of Solvent Effects On The Ground And Excited States Of Endohedral Tri-Scandium Nitride C80 Fullerene Coupled With Zinc Phthalocyanine And Metal-Free Phthalocyanine Using Dft-Pcm Method, Timilsina Prasad Timlsina

Open Access Theses & Dissertations

The photovoltaic active materials composed of endohedral metafullerene and phthalocyanine derivatives are known as excellent electron donor-acceptor pairs. The tri-metallic nitride endohedral C80 fullerene exhibits high absorption coefficients in the visible region of the spectrum and has similar electron-accepting abilities as that of C60 fullerene, which can allow for higher efficiencies in OPV devices. In this study, we examine the effect of solvent on the charge transfer excitation energies of Sc3N@C80-ZnPc and Sc3N@C80-H2Pc donor-acceptor molecular complexes. Three different solvents with different polarity - water, toluene, and acetone are used. The solvent is modeled as a polarizable continuum as implemented in …