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Articles 38881 - 38910 of 294589

Full-Text Articles in Physical Sciences and Mathematics

The Library & Generative Ai, Nat Gustafson-Sundell, Mark Mccullough Aug 2023

The Library & Generative Ai, Nat Gustafson-Sundell, Mark Mccullough

Library Services Publications

A demonstration of several AI tools, including ChatGPT, ChatPDF, Consensus, and more. The focus of the session is on potential student uses of the tools and related library initiatives, so we address the limits of ChatGPT as an information source. Librarians can help students learn how to use these tools responsibly and provide leadership on campus as AI is integrated into assignments.

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The Importance Of Recruitment And Retention In Heliophysics: It's Not Just A Pipeline Problem, A. J. Halford, C. M. Bard, A. G. Burrell, R. M. Mcgranaghan, L. B. Wilson Iii, M. Jones Jr, C. Dong, L. Wang, T. I. Pulkkinen, Niescja E. Turner, M. W. Liemohn, J. Klenzing Aug 2023

The Importance Of Recruitment And Retention In Heliophysics: It's Not Just A Pipeline Problem, A. J. Halford, C. M. Bard, A. G. Burrell, R. M. Mcgranaghan, L. B. Wilson Iii, M. Jones Jr, C. Dong, L. Wang, T. I. Pulkkinen, Niescja E. Turner, M. W. Liemohn, J. Klenzing

Physics and Astronomy Faculty Research

A major obstacle in cultivating a robust Heliophysics (and broader scientific) community is the lack of diversity throughout science, technology, engineering, and mathematics (STEM) fields. For many years, this has been understood as a “leaky pipeline” analogy, in which predominately minority students initially interested in STEM gradually fall (or are pushed) out of the field on their way to a scientific research position. However, this ignores critical structural and policy issues which drive even later career Ph.D.s out of a career in Heliophysics. We identify here several systemic problems that inhibit many from participating fully in the Heliophysics community, including …

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Table Of Contents, The Editors Aug 2023

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

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Hydrodynamic Voltammetry Of Fe2+/3+ In Aqueous Deep Eutectic Solvents Towards Redox Flow Batteries, Desiree Mae Prado, Xiaochen Shen, Robert Savinell, Clemens Burda Aug 2023

Hydrodynamic Voltammetry Of Fe2+/3+ In Aqueous Deep Eutectic Solvents Towards Redox Flow Batteries, Desiree Mae Prado, Xiaochen Shen, Robert Savinell, Clemens Burda

Faculty Scholarship

Deep eutectic solvents (DESs) have recently attracted much attention as potential green electrolyte solvents for redox flow batteries. DESs are considered not only as environmentally sustainable but also economically attractive electrolytes because they can be resourced from biological feedstock (alcohols, urea, choline) and are earth-abundant and of low toxicity. Despite these advantages, DESs still have limitations in important aspects such as reactant and ion transport, which is inhibited due to hydrogen-bonding-induced viscosity. Thus, improving the transport properties of redox species in DESs is essential. In addition, we explore the quantitative addition of water to ethaline (a 1:2 choline chloride: ethylene …

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Two New Maneuvering Target Simulation Methods, Yingxuan Li, Zhongxun Wang, Yunlong Dong Aug 2023

Two New Maneuvering Target Simulation Methods, Yingxuan Li, Zhongxun Wang, Yunlong Dong

Journal of System Simulation

Abstract: To verify the performance of maneuvering target tracking algorithm, it's necessary to build a complex motion simulation model similar to the actual target motion situation. A simulation model of maneuvering target with controllable time correlation coefficient is constructed based on the idea of Singer model, and the suitability of Singer's maneuvering target tracking algorithm is verified when the time correlation coefficient does not match. Aiming at the problem that the traditional coordinated turning model only considers the change of normal acceleration, and the tangential acceleration is always assumed to be 0, which is not highly consistent with the actual …

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Phosphorus-Carrying Cascade Molecules: Inner Architecture To Biomedical Applications, Anbazhagan Thirumalai, Noureddine Elboughdiri, Karthick Harini, Koyeli Girigoswami, Agnishwar Girigoswami Aug 2023

Phosphorus-Carrying Cascade Molecules: Inner Architecture To Biomedical Applications, Anbazhagan Thirumalai, Noureddine Elboughdiri, Karthick Harini, Koyeli Girigoswami, Agnishwar Girigoswami

Turkish Journal of Chemistry

Cascade molecules are nearly uniform-sized macromolecules of small molecules or linear polymer cores built around symmetric branching units. A wide range of biological properties can be achieved with phosphorus-containing dendrimers, depending on their terminal functions, ranging from biomaterials to imaging, drug delivery, and acting as a drug by themselves. This feature article presents significant examples of phosphorus-containing dendrimers used to develop biochips, support cell cultures, carry or deliver biomacromolecules and drugs, bioimaging, and combinational benefits. Because of the thermal stability, ferrocene function, and physical and chemical properties of phosphorus, dendrimers show greater rigidity, mobility, and strength. These dendrimers will be …

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Theoretical Analysis Of Oled Performances Of Some Aromatic Nitrogen-Containing Ligands, Mustafa Eli̇k Aug 2023

Theoretical Analysis Of Oled Performances Of Some Aromatic Nitrogen-Containing Ligands, Mustafa Eli̇k

Turkish Journal of Chemistry

It is well-known that tris(8-hydroxyquinoline) aluminum (Alq3) complex and N,N'diphenyl-N,N'-bis(3-methylphenyl)-1,1'- diphenyl-4,4'-diamine compound (TPD) are widely used as electron transfer material (ETL) and hole transfer material (HTL) in organic light emitting diode (OLED) structure, respectively. Considering the reference materials, in the present work, the OLED performances of some cyclic aromatic structures such as 4,4'azopyridine [AZPY], 4,4'-bipyridine [BIPY], 1,2-bis[4'-(4-methylphenyl)2,2':6'2' '-terpyridin6-yl]ethyne (BISTERPY), 5,5'-diamino-2,2'-bipyridine (DABP), dipyrido[3,2-a:2',3'c]phenazine (DPP), 4,7-phenanthroline (PHEN) including nitrogen atom have been theoretically analyzed. It is important to note that B3LYP/6-31G(d) and B3LYP/TZP levels of the theory were taken into account for the calculations about monomeric and dimeric structures, respectively. Additionally, the …

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Preparation And Application Of Caffeic Acid Imprinted Polymer, Şeyda Karaman Ersoy, Esma Tütem, Kevser Sözgen Başkan, Mustafa Reşat Apak Aug 2023

Preparation And Application Of Caffeic Acid Imprinted Polymer, Şeyda Karaman Ersoy, Esma Tütem, Kevser Sözgen Başkan, Mustafa Reşat Apak

Turkish Journal of Chemistry

In the present study, molecularly imprinted polymers were synthesized using caffeic acid (CA) as a template molecule and then used for the extraction of CA and chlorogenic acid (CLA) from complex matrices. Syntheses were carried out in tetrahydrofuran as porogenic solvent using 4-vinyl pyridine, methacrylic acid, acrylamide, and 1-vinyl imidazole as monomers, ethylene glycol dimethacrylate as crosslinker and 2,2'-azobisisobutyronitrile as initiator. In polymerization processes, different ratios of the template:monomer:crosslinker (T:M:CrL) were used to obtain the most suitable polymer. Caffeic acid:4-vinylpiridine:ethylene glycol dimethacrylate's 1:4:16 mole ratio of MIP was determined as the most convenient polymer for CA recognition. In addition, nonimprinted …

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In Vitro Antioxidant Activity Of Alginate Nanoparticles Encapsulating The Aqueous Extract Of Coccinia Grandis L., Walimuni Nayomi Deshani De Silva, Anoja Priyadarshani Attanayake, Liyanage Dona Ashanti Menuka Arawwawala, Desiree Nedra Karunaratne, Geethi Kaushalya Pamunuwa Aug 2023

In Vitro Antioxidant Activity Of Alginate Nanoparticles Encapsulating The Aqueous Extract Of Coccinia Grandis L., Walimuni Nayomi Deshani De Silva, Anoja Priyadarshani Attanayake, Liyanage Dona Ashanti Menuka Arawwawala, Desiree Nedra Karunaratne, Geethi Kaushalya Pamunuwa

Turkish Journal of Chemistry

Bioactive compounds in medicinal plants are more susceptible to preventing oxidative stress. Encapsulation of herbal extracts has empowered the properties and characteristics of bioactive compounds. Nanoencapsulation allows the enhancement of the stability of extracts and targeted drug delivery. The present study aims to determine the antioxidant activity of alginate nanoparticles encapsulating the aqueous extract of Coccinia grandis L. (Family: Cucurbitaceae). The aqueous extract of C. grandis (AqCG) was prepared by using ultrasonication (40 ° C, 20 min, 40 kHz) followed by refluxing (2½ h). The prepared AqCG (1-5 mg/mL) encapsulated alginate nanoparticles were synthesized by ionic gelation with the addition …

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Effects Of Zsm-5 Zeolite On Pyrolysis Of Polystyrene: From Stabilizing To Catalyzing, Qing Yuan Ma, Zhen Huang, Xuan Ren, Jia Jia Zhao, Fu Chen, Li Jun Teng Aug 2023

Effects Of Zsm-5 Zeolite On Pyrolysis Of Polystyrene: From Stabilizing To Catalyzing, Qing Yuan Ma, Zhen Huang, Xuan Ren, Jia Jia Zhao, Fu Chen, Li Jun Teng

Turkish Journal of Chemistry

Nonisothermal pyrolysis measurements of polystyrene (PS)/ZSM-5 zeolite hybrids are conducted in N2 and thermogravimetric results have been kinetically analyzed with different isoconversional methods. Experimental results show that the addition of 5 and 10 wt.% ZSM-5 zeolite has increased the initial pyrolysis temperature of PS while the addition of 20 and 30 wt.% ZSM-5 zeolite can significantly decrease the initial pyrolysis temperature of PS. Elevated activation energy is resulted by adding low zeolite amount whereas reduced activation energy is obtained by adding high ZSM-5 amounts. The effect of zeolite ZSM-5 on PS pyrolysis can thus be observed to transfer from stabilizing …

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Synthesis And Characterization Of Anderson-Evans Type Polyoxometalates, Antibacterial Properties, Hülya Avci Özbek Aug 2023

Synthesis And Characterization Of Anderson-Evans Type Polyoxometalates, Antibacterial Properties, Hülya Avci Özbek

Turkish Journal of Chemistry

In the present work, the new aluminium-substituted polyoxometalates of the Anderson-Evans type have been prepared and structurally defined by the reaction of aluminium (III) chloride hexahydrate and sodium tungstate dihydrate/sodium molybdate dihydrate in an aqueous basic medium. Elemental analysis, FT-IR, TGA, 1H NMR, and 31P NMR analysis revealed that these polyoxometalates had the following formula: [Ph4 P]3 [Al(OH)6 Mo6 O18]·4H2 O 1, [Ph4 P]3 [Al(OH)6 W6 O18]·4H2 O 2, [C7 H10N]3 [Al(OH)6 Mo6 O18]·4H2 O 3, [C7 H10N]3 [Al(OH)6 W6 O18]·4H2 O 4. The compounds 1 and 2 show promising antibacterial activity against gram-positive Staphylcoccus aureus ATCC 25923 and gram-negative …

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Polymer Architecture Effect On Rheology And Segmental Dynamics In Poly (Methyl Methacrylate)-Silica Nanocomposite Melts, Saeid Darvishi, Erkan Şenses Aug 2023

Polymer Architecture Effect On Rheology And Segmental Dynamics In Poly (Methyl Methacrylate)-Silica Nanocomposite Melts, Saeid Darvishi, Erkan Şenses

Turkish Journal of Chemistry

Architecturally different polymer chains lead to fundamentally different rheological responses and internal dynamics, which can be utilized to rationalize advanced thermoplastic nanocomposites with tunable mechanical behavior. In this work, three model poly (methyl methacrylate) (PMMA) polymers with linear, bottlebrush, and star architectures with the same total molar mass were investigated in their neat form, and nanocomposites with well-dispersed silica nanoparticles using rheology and broadband dielectric spectroscopy (BDS). The master curves of the dynamic moduli obtained by time-temperature superposition (TTS) over the entire range from the Rouse regime to the terminal flow and a sequence of significantly different relaxation modes were …

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Synthesizinge A Novel Zr2al-Gns Max Phase Ceramic With Superior Electrical Properties Using Pressureless Sintering Technique, Dumooa R. Hussein, Khalid K. Abbas, Ahmed M.H. Abdulkadhim Al-Ghaban Aug 2023

Synthesizinge A Novel Zr2al-Gns Max Phase Ceramic With Superior Electrical Properties Using Pressureless Sintering Technique, Dumooa R. Hussein, Khalid K. Abbas, Ahmed M.H. Abdulkadhim Al-Ghaban

Turkish Journal of Chemistry

A unique Zr2 Al-GNS MAX phase ceramic supported nanographene sheet was prepared using a cost-effective pressureless sintering technique under relatively low temperature. An experimental investigation was conducted to explore the lattice parameters using different temperatures, such as 1000, 1150, and 1300 °C. To characterize the crystal structure of the MAX phase ceramic, X-ray diffraction, field emission scanning electron microscopy imaging, energy-dispersive X-ray spectroscopy (EDX), high-resolution transmission electron microscopy (HRTEM), and selected area diffraction (SAED) were utilized. The results revealed that the pressureless sintering technique was successfully utilized to synthesize the Zr2 Al-GNS MAX phase ceramic under 1150 °C with a …

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Electronic Structures And Dielectric Function Of (5, 5) Cnt-C2h4o System: A First-Principles Study On The Detection Capability Of Cnt For Gas Sensing Applications, Alvanh Alem Pido, Art Anthony Munio Aug 2023

Electronic Structures And Dielectric Function Of (5, 5) Cnt-C2h4o System: A First-Principles Study On The Detection Capability Of Cnt For Gas Sensing Applications, Alvanh Alem Pido, Art Anthony Munio

Turkish Journal of Chemistry

Carbon nanotubes (CNTs) are known to have a wide range of applications in various fields of discipline. In this research, the ability of metallic armchair (5, 5) CNT to detect acetaldehyde (C2 H4 O) was investigated using first-principles density functional theory (DFT) as implemented in Quantum ESPRESSO with the Generalized Gradient Approximation (GGA). Accordingly, it was found that C2 H4 O preserved the metallic behavior of the CNT. However, some bands are found to have overlapped in both the valence and conduction regions of the electronic structures of the resulting system that are mainly caused by the p orbitals of …

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Waste Jean Derived Self N-Containing Activated Carbon As A Potential Electrode Material For Supercapacitors, Yavuz Gökçe Aug 2023

Waste Jean Derived Self N-Containing Activated Carbon As A Potential Electrode Material For Supercapacitors, Yavuz Gökçe

Turkish Journal of Chemistry

The rapid rise of the world population increases the annual amount of waste textile products. Textile products create a significant amount of CO2 , water, and chemical footprints during production. Therefore, the reusability of textile products has an important environmental and economic impact. Waste denim was used in this study to produce activated carbon (AC) samples as the alternative substance for supercapacitor electrodes. Characterisation studies showed that AC samples contain nitrogen originating from the elastane in the denim structure. Electrochemical characterisation tests proved the pseudocapacitive behaviour of the denim-derived AC due to the nitrogen content. Specific capacitance values observed for …

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Acid-Base Potentiometric Titration Using A Stainless Steel Electrode Without Oxidative Treatment, Javier E. Vilasó-Cadre, Daniel Benítez-Fernández, Ilse A. López-Álvarez, F. Yuliana Tovar-Vázquez, María A. Arada-Pérez, Iván A. Reyes-Domínguez Aug 2023

Acid-Base Potentiometric Titration Using A Stainless Steel Electrode Without Oxidative Treatment, Javier E. Vilasó-Cadre, Daniel Benítez-Fernández, Ilse A. López-Álvarez, F. Yuliana Tovar-Vázquez, María A. Arada-Pérez, Iván A. Reyes-Domínguez

Turkish Journal of Chemistry

An AISI 304 stainless steel laminar electrode without oxidative treatment was investigated for the potentiometric titration of hydrochloric acid with sodium hydroxide. The proposed electrode was obtained from metalworking cuttings. Scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray fluorescence spectroscopy and X-ray diffraction were used to study the surface morphology and chemical composition of the electrode. The electrode showed a sensitivity of 59.18 ± 0.37 mV/pH, which was reproducible under intermediate conditions. Potentiometric titration showed a curve with deviations from pH 9.5 with respect to the glass electrode. However, this did not affect the quantification as the jumps of the …

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Framing And Intentionality In Artificial Intelligence Poetry, Alyson Elaine Marie Nichols Aug 2023

Framing And Intentionality In Artificial Intelligence Poetry, Alyson Elaine Marie Nichols

Student Theses and Dissertations

As natural language generation expands, increasing attention has been paid to neural networks and other machine learning techniques. This study offers a cheaper, simpler approach in the field of poetry generation. The Empath system uses a random-grammar model to constrain creativity with syntactical rules in order to produce novel and valuable poetry after the style of Emily Dickinson. It pays specific attention to using related words to create a sense of coherence and implements a framing system to prove that its creative choices are intentional. A survey of 118 students and teachers at Arkansas State University shows that Empath’s products …

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Euler's Infinite Product Formula Of Sine, Sarah Joy Kinnison Aug 2023

Euler's Infinite Product Formula Of Sine, Sarah Joy Kinnison

Student Theses and Dissertations

Euler’s infinite product formula of sine is a classical math problem that was discovered by Euler in 1748 and is still generating interest and being researched by mathematicians today. The goal of this research is to analyze current published proofs for the formula and find those proofs that are most accessible to upper level undergraduate math students. Three different proofs are found to be suitable for our purpose, and two these proofs are modified so that they are easier to understand. Some well-known applications of the Euler’s formula are the Basel problem and Bernoulli numbers.

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The Potential Use Of Madtom Catfishes (Ictaluridae: Noturus) As Conservation Tools For Headwater Streams Of The Southeastern United, Brittany Latrice Mccall Aug 2023

The Potential Use Of Madtom Catfishes (Ictaluridae: Noturus) As Conservation Tools For Headwater Streams Of The Southeastern United, Brittany Latrice Mccall

Student Theses and Dissertations

Freshwater ecosystems are among the most modified and threatened environments, with increased anthropogenic activities causing habitat degradation, alteration to environmental function and structure, overexploitation of resources, and widespread distribution of non-native species leading to loss of biodiversity. A common conservation management strategy is to create protective areas that encompass the distribution of at-risk species. The objective of protected areas is to address issues that have been cited as the three primary threats to freshwater environments: land-use disturbances, altered hydrology, and introduction of non-native species. There are many methods to delineate protected areas including the use of surrogate species, a management …

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Evaluation Of Site-Specific, Zone Management In Northeast Arkansas Cotton, Nelson Ray Benson Aug 2023

Evaluation Of Site-Specific, Zone Management In Northeast Arkansas Cotton, Nelson Ray Benson

Student Theses and Dissertations

Temporal and spatial variations in crop performance are common in agricultural production fields in northeastern Arkansas. With the alluvial soils of the Mississippi Delta region, within-field soil texture can range from coarse sand to heavy clay. Such variability influences chemical and physical soil properties that affect yield potential of the region’s commercial cropping systems. With advances in precision management, delineating large commercial fields into zones of homogenous production potential could increase profitability and improve efficiency. Standardized criteria for defining homogeneity within potential delineation zones have not been developed or field-tested in the region, which includes Mississippi County, Arkansas, the largest …

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R&D And Experimental Research Of Pressure-Preserved Triggering Device For Horizontal Pressure-Preserved Coring In Coal Mines, Huang Wei, Chen Ling, Li Jianan, Fan Dong, Yang Mingqing, Liu Guikang, Xu Qing, Ma Changliang Aug 2023

R&D And Experimental Research Of Pressure-Preserved Triggering Device For Horizontal Pressure-Preserved Coring In Coal Mines, Huang Wei, Chen Ling, Li Jianan, Fan Dong, Yang Mingqing, Liu Guikang, Xu Qing, Ma Changliang

Coal Geology & Exploration

Gas content is an important evaluation index of safe coal mining, as well as the exploitation and utilization of coalbed methane resources. Pressure-preserved coring is an effective way to improve the measurement accuracy of gas content in coal seams. Aiming at the special operating conditions of horizontal pressure-preserved coring in coal mines and based on the principle and technology of pressure- and gas-preserved coring in coal mines, this study developed a pressure-preserved triggering device and systematically designed the key components of the device, such as the sealing and pressure-preserved unit, the hydraulic drive module, and the salvager-unstuck mechanism between the …

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Principle And Technology Of In-Situ Magnetically Controlled Multidirectional Pressure-Preserved Coring In The Coal Mine, Liu Guikang, Li Cong, You Zhenxi, Hu Yunqi, Huang Wei, Wang Ruize, Xu Meng Aug 2023

Principle And Technology Of In-Situ Magnetically Controlled Multidirectional Pressure-Preserved Coring In The Coal Mine, Liu Guikang, Li Cong, You Zhenxi, Hu Yunqi, Huang Wei, Wang Ruize, Xu Meng

Coal Geology & Exploration

Obtaining the in-situ physical and mechanical parameters of coal-rock mass is the primary task for the development of deep coal resource. Accurate measurement of the in-situ parameters of gas is the basic guarantee to realize the safe mining of coal. In view of the technical challenges of inaccurate measurement of in-situ gas parameters in coal mine, the idea of multi-directional pressure-preserved coring technology based on magnetic force control was proposed with consideration to the technical characteristics of coring in underground coal mines. Specifically, a self-triggered magnetically controlled pressure-preserved controller was designed based on the characteristics of the composite magnetic field. …

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Simulation Optimization And Applications Of Pressure-Preserved Triggering Device For Coring In Deep Coal Mines, Shi Xiaojun, Li Minghui, Liu Guikang, You Zhenxi, Guo Lihua, Hou Lele, Zhao Xiang Aug 2023

Simulation Optimization And Applications Of Pressure-Preserved Triggering Device For Coring In Deep Coal Mines, Shi Xiaojun, Li Minghui, Liu Guikang, You Zhenxi, Guo Lihua, Hou Lele, Zhao Xiang

Coal Geology & Exploration

The pressure-preserved controller is the core component of pressure- and gas-preserved coring equipment used in deep coal mines. Its pressure-preserved capability and sealing performance are the key to pressure- and gas-preserved coring technology. Given that the existing pressure-preserved controller exhibits low initial sealing specific pressure and poor sealing performance when its initial sealing force is provided only by gravity, this study innovatively designed a pressure-preserved triggering device for coring, aiming to provide initial sealing specific pressure required for the sealing of the pressure-preserved controller. Then, this study conducted numerical simulations of the operating process of the triggering device using the …

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Development Of Self-Locking Transfer Mechanism For Coal Samples From Pressure-Preserved Coring In Deep Mining, Zhu Pengfei, Li Jianan, Li Ju, Fu Chenghang, Ye Banghua Aug 2023

Development Of Self-Locking Transfer Mechanism For Coal Samples From Pressure-Preserved Coring In Deep Mining, Zhu Pengfei, Li Jianan, Li Ju, Fu Chenghang, Ye Banghua

Coal Geology & Exploration

Pressure-preserved coring technology can directly store the collected deep coal samples at the bottom of the hole, so as to minimize the gas loss during the coring process. Besides, pressure transfer and testing of the pressure-preserved rock core is a technical prerequisite for the accurate determination of gas content. Then, how to achieve the precise docking from pressure-preserved coring to pressure transfer and testing has become a key technical difficulty that needs to be overcome urgently. Therefore, the research was carried out around the self-locking transfer mechanism, which is the core component of the docking transfer between the pressure-preserved coring …

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Closure Trajectory Model Of Pressure-Preserved Controller For Coring In Coal Seam Surface Well, Guo Da, Zhang Yiwei, Wang Dingming, Fang Xin, Yang Bengao, Guo Lihua, Hou Lele, Zhao Xiang Aug 2023

Closure Trajectory Model Of Pressure-Preserved Controller For Coring In Coal Seam Surface Well, Guo Da, Zhang Yiwei, Wang Dingming, Fang Xin, Yang Bengao, Guo Lihua, Hou Lele, Zhao Xiang

Coal Geology & Exploration

The traditional method of coal exploration is to obtain coal samples using an open coring tool and estimate the gas loss through theoretical calculations. However, the measured gas content of these coal samples is generally low, significantly impeding the development and utilization of coalbed methane and compromising the safety of coal mining operations. To meet the demands of deep coal exploration, an innovative pressure-preserved coring tool was specifically designed for the coal seam surface wells. This tool has a total length of 6.7 m and can extract a 3 m long pressure-preserved coal core sample at a single time. In …

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Fractal Theory-Based Permeability Model Of Fracture Networks In Coals, Xia Binwei, Liao Chuanbin, Luo Yafei, Ji Kainan Aug 2023

Fractal Theory-Based Permeability Model Of Fracture Networks In Coals, Xia Binwei, Liao Chuanbin, Luo Yafei, Ji Kainan

Coal Geology & Exploration

Fractures in coal reservoirs, which act as the major seepage pathways for coalbed methane (CBM), determine the permeability and CBM productivity of coal reservoirs. Research on the relationships between fracture structures and reservoir permeability is of great theoretical and practical significance for the accurate prediction of CBM productivity. Based on the classical cubic law-based permeability model, as well as the fractal theory, fracture network structures, and effective stress, this study built a permeability model containing complex bending fractures, which was then combined with the S & D (Shi-Durucan) model to build the permeability model of fractured coals under the action …

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A Method For Classification Of Surrounding Rock Based On The Excavatability Performance And Adaptability Of Tunnel Boring Machines And Its Applications, Liu Jiawei, Zhang Sheng, Chen Zhao, Yang Zhanbiao, Ji Panjun, Wei Yonghui Aug 2023

A Method For Classification Of Surrounding Rock Based On The Excavatability Performance And Adaptability Of Tunnel Boring Machines And Its Applications, Liu Jiawei, Zhang Sheng, Chen Zhao, Yang Zhanbiao, Ji Panjun, Wei Yonghui

Coal Geology & Exploration

The varying geological conditions of the surrounding rocks of coal mine roadways influence the wide application of full-face rock tunnel boring machines (TBMs). Therefore, accurately assessing the excavatability of rock masses in coal mines and the rock adaptability of TBMs is crucial for the efficient operation of TBMs. Based on the evaluation results of the parameters and excavatability of rock masses, this study built a classification model for rock mass excavatability using the technique for order preference by similarity to ideal solution (TOPSIS). Furthermore, combining the correlation analysis between the [BQ] values of different geological conditions and the utilization ratio …

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Drillability And Mechanical Parameters Of Laser Hot Cracking Sandstones, Yang Lei, Yang Bengao, Liu Junjun, Zhou Xuemin, Xie Jing, Wang Chen, Guo Chenchen, Gao Mingzhong Aug 2023

Drillability And Mechanical Parameters Of Laser Hot Cracking Sandstones, Yang Lei, Yang Bengao, Liu Junjun, Zhou Xuemin, Xie Jing, Wang Chen, Guo Chenchen, Gao Mingzhong

Coal Geology & Exploration

Over recent years, shallow coal resources that can be easily mined have been gradually exhausted. As a result, conventional drilling techniques tend to face challenges such as low rock-breaking efficiency, high drilling costs, and environmental pollution in the exploration and exploitation of deep coal resources. Therefore, there is an urgent need to introduce a new auxiliary rock-breaking technique for drilling. Focusing on the new laser-assisted rock-breaking technology, this study systematically conducted mechanical and drillability tests on sandstones after laser irradiation for different durations, aiming to explore the temporal and spatial evolution of the temperature field of hard sandstones, the propagation …

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Physical And Mechanical Properties Of Thermal Insulation Materials For In-Situ Temperature-Preserved Coring Of Deep Rocks, Xue Shouning, He Zhiqiang, Li Cong, Yu Bo, Lu Xuelian, Liu Wenyue, Yang Jianping, Wei Zijie Aug 2023

Physical And Mechanical Properties Of Thermal Insulation Materials For In-Situ Temperature-Preserved Coring Of Deep Rocks, Xue Shouning, He Zhiqiang, Li Cong, Yu Bo, Lu Xuelian, Liu Wenyue, Yang Jianping, Wei Zijie

Coal Geology & Exploration

High temperature affects deep coal mining and other engineering activities. However, conventional coring methods for terrestrial hard rocks lack temperature-preserved measures, ignoring the effects of temperature on the physical and mechanical properties of rocks. Consequently, the parameters obtained are subjected to distortion, affecting the safe and efficient mining of resources such as deep coals. To make breakthroughs in the development of in-situ temperature-preserved coring technologies for deep rocks, this study proposed using the hollow glass microsphere/epoxy resin (HGM/EP) as thermal insulation materials and the physical and mechanical properties. The results are as follows: (1) With an increase in the HGM …

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Butte Priority Soils Operable Unit (Bpsou) Final Insufficiently Reclaimed (Ir) Sites – Field Sampling Plan (Fsp) Butte Remediation Evaluation System (Bres) No. 31 Waste Dump #5, Mike Mcanulty Aug 2023

Butte Priority Soils Operable Unit (Bpsou) Final Insufficiently Reclaimed (Ir) Sites – Field Sampling Plan (Fsp) Butte Remediation Evaluation System (Bres) No. 31 Waste Dump #5, Mike Mcanulty

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.

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