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Mining-Induced Shear Deformation And Permeability Evolution Law Of Crushed Rock Mass In Fault Zone, Li Qiang, Ma Dan, Zhang Jixiong, Liu Yong, Hou Wentao Aug 2023

Mining-Induced Shear Deformation And Permeability Evolution Law Of Crushed Rock Mass In Fault Zone, Li Qiang, Ma Dan, Zhang Jixiong, Liu Yong, Hou Wentao

Coal Geology & Exploration

To explore the mechanism of water inrush induced by fault activation under mining, experimental studies were conducted on the shear deformation and permeability evolution of crushed rock mass in fault zone. Specifically, a set of compression-shear-seepage test system for crushed rock mass was designed according to the principle of fluid-solid coupling, with the coupling process of shear deformation and seepage realized. On this basis, the shear-seepage coupling test was carried out for the crushed rock mass under the influence of multiple factors. Thus, the influence of particle size distribution and initial porosity of crushed rock mass on porosity and permeability …

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New Faculty Guide, 2023-2024, University Of Mississippi. Provost Aug 2023

New Faculty Guide, 2023-2024, University Of Mississippi. Provost

New Faculty

No abstract provided.

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Quantification And Reduction Of Uncertainty In Seismic Resilience Assessment For A Roadway Network, Vishnupriya Jonnalagadda, Ji Yun Lee, Seyed Hooman Ghasemi Aug 2023

Quantification And Reduction Of Uncertainty In Seismic Resilience Assessment For A Roadway Network, Vishnupriya Jonnalagadda, Ji Yun Lee, Seyed Hooman Ghasemi

Henry M. Rowan College of Engineering Departmental Research

The nation’s transportation systems are complex and are some of the highest valued and largest public assets in the United States. As a result of repeated natural hazards and their significant impact on transportation functionality and the socioeconomic health of communities, transportation resilience has gained increasing attention in recent years. Previous studies on transportation resilience have heavily emphasized network functionality during and/or following a scenario hazard event by implicitly assuming that sufficient knowledge of structural capacity and environmental/service conditions is available at the time of an extreme event. However, such assumptions often fail to consider uncertainties that arise when an …

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2012 Great Day Program, State University Of New York At Geneseo Aug 2023

2012 Great Day Program, State University Of New York At Geneseo

GREAT Day Programs

SUNY Geneseo’s Sixth Annual GREAT Day.

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Stimulation Effect Of Pulsed Ultrasonic Excitation On Coal Pores With Full-Scale Pore Sizes, Lin Haifei, Qiu Yue, Han Shuangze, Gao Haidong, Yang Erhao, Wang Ruizhe, Yan Min Aug 2023

Stimulation Effect Of Pulsed Ultrasonic Excitation On Coal Pores With Full-Scale Pore Sizes, Lin Haifei, Qiu Yue, Han Shuangze, Gao Haidong, Yang Erhao, Wang Ruizhe, Yan Min

Coal Geology & Exploration

This study aims to further investigate the stimulation effect of pulsed ultrasonic excitation on coal pore structures. Using an ultrasonic excitation test system for gas-containing coals, this study conducted ultrasonic excitation tests on coals under continuous and interactive pulses with ultrasonic power of 800 W and 1000 W. Through low-pressure CO2 adsorption tests, low-temperature nitrogen adsorption tests, and the mercury injection capillary pressure (MICP) tests, this study explored the evolutionary patterns of parameters of various coal pores with full-scale pore sizes, including macropores (> 50 nm), mesopores (2‒50 nm), and micropores (< 2 nm). The test results are as follows: (1) Pulsed ultrasonic waves can expand coal pores. The pore volume of coals was primarily provided by micropores and macropores, with mesopores representing a small proportion. The specific surface area of various coal pores was in the order of micropores > mesopores > macropores. (2) Compared with those having …

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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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2023 School Of Engineering Vision Award Winners Recognized, University Of Dayton Aug 2023

2023 School Of Engineering Vision Award Winners Recognized, University Of Dayton

Blog: The Dayton Engineer

The University of Dayton School of Engineering Vision Awards recognize the innovation, creativity, entrepreneurial thinking and outstanding performance of our faculty and staff for their work as it relates to our School's values of community, innovation, excellence, and engagement and service.

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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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Cover And Contents Aug 2023

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.

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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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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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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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Structural Configuration Of Amorphous Silica Surface With Different Terminating Groups Using Classical And Ab Initio Molecular Dynamics, Md Azharul Islam Aug 2023

Structural Configuration Of Amorphous Silica Surface With Different Terminating Groups Using Classical And Ab Initio Molecular Dynamics, Md Azharul Islam

Student Theses and Dissertations

Silica has numerous applications across various sectors of technology, including concrete production, glass production, food additives, and semiconductor technology. The surface interaction properties of amorphous silica are crucial, yet many aspects of these interactions, particularly with passivating groups, are still not fully understood because amorphous silica’s nature is non-periodic. In this study, computational simulations are used to understand the bonding mechanism and atomic structure of the amorphous silica surfaces with different passivating groups. Amorphous silica surfaces are generated by melt-quench dynamics using classical molecular dynamics (MD). Then, subdomains of these surfaces containing an undercoordinated surface atom are selected for ab …

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Exploring Teachers’ Perceived Sense Of Efficacy On Black Student Achievement In Reading For Grades 5–8, Bryan David Lowe Aug 2023

Exploring Teachers’ Perceived Sense Of Efficacy On Black Student Achievement In Reading For Grades 5–8, Bryan David Lowe

Student Theses and Dissertations

The purpose of this study was to learn from the experiences of teachers who have had at least five Black middle school students (Grades 5–8) meet or exceed their performance level expectations on the English Language Arts TNReady assessment by identifying the factors that contributed to teachers’ sense of efficacy related to their experience. Using social cognitive theory as the theoretical framework and self-efficacy theory as a focal point, this qualitative phenomenological study examined how dimensions of teacher efficacy such as instructional strategies and teacher-student relationships, which include classroom management and student engagement practices, may provide avenues for increasing academic …

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Criticism Of Parasocial Interaction Theory In Public Relations Research: A Fan Studies Application Through Bts Army Autoethnographies And Situational Theory Of Publics, Emma Carroll Hudson Aug 2023

Criticism Of Parasocial Interaction Theory In Public Relations Research: A Fan Studies Application Through Bts Army Autoethnographies And Situational Theory Of Publics, Emma Carroll Hudson

Theses - ALL

This thesis investigates the reliability and ethics of parasocial interaction theory (PSI) for public relations (PR) practitioners to rely on when creating content or campaigns for fans. Drawing on literature from fan studies and public relations theories, this research proposes situational theory of publics as an alternative theory when researching the motivations and passions of fandom communities. The researcher employs a qualitative multimethod design that integrates individual in-depth interviews (IDIs) with PR practitioners in fan engagement specialist roles and autoethnographic essays written by BTS’ ARMY–a fandom that supports popular K-pop group Bangtan Soyeondan (BTS). The interviews and essays are coded …

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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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Urban Resistance To Occupation: An Underestimated Element Of Land Warfare, Kevin D. Stringer, Jelle J. H. Hooiveld Aug 2023

Urban Resistance To Occupation: An Underestimated Element Of Land Warfare, Kevin D. Stringer, Jelle J. H. Hooiveld

The US Army War College Quarterly: Parameters

With the world trending toward urbanization, and Russia and China acting aggressively toward Ukraine and Taiwan, respectively, the conduct of irregular warfare in built-up environments—specifically, urban resistance to occupation—merits greater study. The authors’ Dutch-language and primary source research on the Netherlands’ World War II urban resistance to German occupation makes this article unique. It provides deeper insights into the occupation experiences of a highly urbanized, densely populated country in which clandestine underground and auxiliary elements played paramount roles in resistance efforts for most of the occupation period. It also illustrates the feasibility of overt, guerrilla-based activity in urban environments during …

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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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