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Articles 57511 - 57540 of 302433

Full-Text Articles in Physical Sciences and Mathematics

Ready-To-Wear Strain Sensing Gloves For Human Motion Sensing, Sara S. Mechael, Yunyun Wu, Yiting Chen, Tricia Breen Carmichael Jun 2021

Ready-To-Wear Strain Sensing Gloves For Human Motion Sensing, Sara S. Mechael, Yunyun Wu, Yiting Chen, Tricia Breen Carmichael

Chemistry and Biochemistry Publications

Integrating soft sensors with wearable platforms is critical for sensor-based human augmentation, yet the fabrication of wearable sensors integrated into ready-to-wear platforms remains underdeveloped. Disposable gloves are an ideal substrate for wearable sensors that map hand-specific gestures. Here, we use solution-based metallization to prepare resistive sensing arrays directly on off-the-shelf nitrile butadiene rubber (NBR) gloves. The NBR glove acts as the wearable platform while its surface roughness enhances the sensitivity of the overlying sensing array. The NBR sensors have a sheet resistance of 3.1 ± 0.6 Ω/sq and a large linear working range (two linear regions ≤70%). When stretched, the …

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Feasibility Study On The Principle Of Punching-Shearing Composite Rock Fragmentation Mode Of Connecting Holes In Rock Strata, Wang Chuanliu Jun 2021

Feasibility Study On The Principle Of Punching-Shearing Composite Rock Fragmentation Mode Of Connecting Holes In Rock Strata, Wang Chuanliu

Coal Geology & Exploration

Replacing roadway with borehole is an important research direction of underground coal mine drilling technology, which has the advantages of high efficiency and low cost. However, in the construction of large diameter connecting holes in rock strata, the multi-stage reaming method has such problems as long lifting and drilling time and low efficiency of hole formation. This paper proposes the principle of punching-shearing composite rock fragmentation through structural and technological innovation without changing the configuration of drilling equipment. It is a creative combination of punching rock fragmentation of high-pressure water-impactor-inner bit rock and shearing rock fragmentation of drilling rig-drilling pipe-outer …

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Application And Development Of Permanent Magnet Torque Motor In Down-Hole Tools For Oil And Gas Drilling And Production, Li Wei, Deng Lang, Zou Xing, Xia Yang, Chen Xi Jun 2021

Application And Development Of Permanent Magnet Torque Motor In Down-Hole Tools For Oil And Gas Drilling And Production, Li Wei, Deng Lang, Zou Xing, Xia Yang, Chen Xi

Coal Geology & Exploration

Permanent magnet torque motor is a kind of a power driving device with great development potential. It has several advantages, such as high torque density, fast response speed, strong overload capacity, high efficiency and energy saving, therefore, it possesses wide application prospects in many fields in both industrial production and daily life and so on. In view of the current application overview and technical requirements of permanent magnet torque motors in oil and gas drilling and production down-hole intelligent tools, firstly, this paper briefly introduces the structure composition and working principle of permanent magnet torque motor. Then, it elaborates the …

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Effect Of Load On Adsorption Characteristics Of Remolded Coal, Dai Juhua, Wang Zhaofeng, Li Xuechen, Li Yanfei, Yue Jiwei Jun 2021

Effect Of Load On Adsorption Characteristics Of Remolded Coal, Dai Juhua, Wang Zhaofeng, Li Xuechen, Li Yanfei, Yue Jiwei

Coal Geology & Exploration

In view of the difficulty in preparing the coal with broken soft structure intact, it needs to be processed into remolded coal. In order to study the influence of suppression loads on the physical characteristics of coal, the micro-pore structure and adsorption characteristics of remolded coal under different molding loads were discussed based on the pore test experiment of low temperature liquid nitrogen and the methane adsorption experiment of high pressure capacity method. The results show that: The pore volume of micropores and pores decreases slightly with the increase of molding load, the specific surface area increases slightly with the …

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Distribution And Enrichment Of Pollutants From Underground Gasification Of Bituminous Coal In Huating Mining Area, Zhu Lihui, Feng Beizhan, Hu Yongxing, Wang Mingzhong Jun 2021

Distribution And Enrichment Of Pollutants From Underground Gasification Of Bituminous Coal In Huating Mining Area, Zhu Lihui, Feng Beizhan, Hu Yongxing, Wang Mingzhong

Coal Geology & Exploration

In order to study the enrichment and distribution of pollutants from the underground gasification of bituminous coal in Huating Mining Area, and to evaluate the environmental factors of the underground gasification of bituminous coal, with an underground gasification simulation experimental platform system, this paper studies the enrichment of heavy metal pollutants in tar and gasification residues during gasification process by means of different oxygen-rich-water gasification experiments and pyrolysis experiments of coal samples in different sizes. The results show that the pyrolytic tar of bituminous coal tends to increase as its size increases, and the yield increases first and then decreases. …

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Experimental Study On Multi-Scale Pore Structure Characteristics Of Tar-Rich Coal In Yushenfu Mining Area, Shen Yanjun, Wang Xu, Zhao Chunhu, Wang Shengquan, Guo Chen, Shi Qingmin, Ma Wen Jun 2021

Experimental Study On Multi-Scale Pore Structure Characteristics Of Tar-Rich Coal In Yushenfu Mining Area, Shen Yanjun, Wang Xu, Zhao Chunhu, Wang Shengquan, Guo Chen, Shi Qingmin, Ma Wen

Coal Geology & Exploration

Extracting oil and refining gas from oil-rich coal is an important measure to make up for the shortage of oil and gas supply in China. The research on pore development characteristics and permeability of tar-rich coal will help to better develop and utilize tar-rich coal. Taking the tar-rich coal in Yushenfu mining area as the research object, this paper studies the multi-scale pore structure and the whole segment pore characterization of tar-rich coal by such methods as low-temperature liquid nitrogen adsorption, mercury intrusion porosimetry, nuclear magnetic resonance and gas permeability measurement method. Based on the test results of multi-scale pore …

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Organic Geochemistry Of The Jurassic Tar-Rich Coal In Northern Shaanxi Province, Zhang Ning, Xu Yun, Qiao Junwei, Ning Shuzheng Jun 2021

Organic Geochemistry Of The Jurassic Tar-Rich Coal In Northern Shaanxi Province, Zhang Ning, Xu Yun, Qiao Junwei, Ning Shuzheng

Coal Geology & Exploration

The organic geochemical characteristics of tar-rich coal are of great significance to study the paleosedimentary environment and evolution of coal seams. Taking coal samples from 6 main coal seams of Yan’an Formation in Northern Shaanxi Province as the research object, this paper analyses the organic geochemical characteristics of coal seams by coal quality analysis and gas chromatography-mass spectrometry. The results showed that coal samples had a high abundance of chloroform asphalt "A" and a low saturated hydrocarbon/aromatic hydrocarbon ratios, characterized by the unimodal pattern of n-alkanes and dominated by medium chainsaturated hydrocarbons. The ratios of Pr/C17, Ph/C18 …

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Analysis Of Interlayer Interference In Combined Development Of Coalbed Methane Wells And Discussion On Combined Production Methods：A Case Study Of Shoushan No.1 Coal Mine In Pingdingshan, Xu Yaobo Jun 2021

Analysis Of Interlayer Interference In Combined Development Of Coalbed Methane Wells And Discussion On Combined Production Methods：A Case Study Of Shoushan No.1 Coal Mine In Pingdingshan, Xu Yaobo

Coal Geology & Exploration

The combined development of multiple coal seams is a key technology to increase the production of single CBM wells. However, in engineering practice, most coal seams have interlayer interference problems, resulting in an insignificant increase in combined development gas production. In order to improve the gas production and development efficiency of combined development in coalbed methane wells, taking the combined production of coalbed methane in the No.4-2 coal seam and the No.2-1 coal seam of the Shoushan No.1 Coal Mine in Pingdingshan as an example, this paper analyses the influence factors and interference rules of interlayer interference, and proposes the …

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Green Detection Method Of Coal Burning Area In Northern Shaanxi Based On Microbial Hydrocarbon Detection Technology, Duan Zhonghui, Ma Li, Hao Chun, Wang Lengyao, Mei Hai Jun 2021

Green Detection Method Of Coal Burning Area In Northern Shaanxi Based On Microbial Hydrocarbon Detection Technology, Duan Zhonghui, Ma Li, Hao Chun, Wang Lengyao, Mei Hai

Coal Geology & Exploration

Coal seams contain all kinds of light hydrocarbons. When coal seams are burned, the integrity of overlying strata is destroyed, which provides a good channel for hydrocarbon escape from the coal seam. This process conforms to the principle of light hydrocarbon microseepage. Then, microseepage associated microbial hydrocarbon detection technology is introduced to test its recognition ability of coal seam burning area. In Haojialiang Coal Mine of Jurassic Coalfield in northern Shaanxi, two survey lines were tested and butane bacteria was selected as microbial detection index. After microbial analysis process such as soil sampling, microbial culture, and colony count, combined with …

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Borehole-Roadway Seismic-While-Mining Tomography Using Correlation Time Difference, Wang Yunhong, Wang Baoli, Cheng Jianyuan, Cui Weixiong, Jin Dan Jun 2021

Borehole-Roadway Seismic-While-Mining Tomography Using Correlation Time Difference, Wang Yunhong, Wang Baoli, Cheng Jianyuan, Cui Weixiong, Jin Dan

Coal Geology & Exploration

Using shearer as a source, seismic-while-mining(SWM) technology has realized dynamic, accurate and green intelligent detection in fully mechanized mining faces, and can be used to detect static geological anomaly and dynamic mining geological disasters within the work face. Conventional SWM observation system has the defect of blind area. To solve this problem, a new observation system with detectors installed in both roadway and within boreholes are proposed, which effectively improved the imaging range. Based on seismic interferometry principle, using frequency domain correlation algorithm, this paper turns the SWM signal to explosive source signal, and computes the equivalent shot sets. In …

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Occurrence Characteristics And Resource Potential Evaluation Of Tar-Rich Coal For No.5-2Coal Seam In Shenfu Mining Area, Li Huabing, Yao Zheng, Li Ning, Gao Jun, Xie Qing, Wang Qiang Jun 2021

Occurrence Characteristics And Resource Potential Evaluation Of Tar-Rich Coal For No.5-2Coal Seam In Shenfu Mining Area, Li Huabing, Yao Zheng, Li Ning, Gao Jun, Xie Qing, Wang Qiang

Coal Geology & Exploration

With the promotion of clean and efficient utilization of coal and the demand for high-quality development in the middle section of the Yellow River, the transformation and upgrading of coal industry is imperative in Yulin, and the exploitation of tar-rich coal one of the important directions. By organizing and making use of mass drill data, and in combination with the minefield underground spot sampling and regional geology, tar-yield characteristics and tar-rich coal occurrence features of tar-rich coal in No.5-2 coal seam in Shenfu Mining Area are analyzed in detail. Based on analytic hierarchy process, this paper takes resource allocation, …

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Research On Wireline Sealed Coring Equipment And Technology For Coalbed Methane Content Determination, Long Weicheng, Sun Siqing Jun 2021

Research On Wireline Sealed Coring Equipment And Technology For Coalbed Methane Content Determination, Long Weicheng, Sun Siqing

Coal Geology & Exploration

Coalbed methane content is an important technical parameter for the development and utilization of coalbed methane resources and the prevention and control of mine gas. In order to solve the problem of deviation of coalbed methane content measurement results caused by inaccurate estimation of coal core loss gas volume in the process of surface well coalbed methane content determination, the wireline sealing coring device for surface well coal seam is developed, and the wireline sealing coring technology for surface well coal seam is proposed. The upper end of the coal seam wireline sealing coring device is designed with wireline fishing …

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Experimental Study On The Influence Of Coal-Based Co2 Geological Storage On Roof Fracture Conductivity, Zhu Shiliang, Shao Liwei, Zhou Xiaozhi, Cao Yutong, Zhang Kun, Wang Jiandong Jun 2021

Experimental Study On The Influence Of Coal-Based Co2 Geological Storage On Roof Fracture Conductivity, Zhu Shiliang, Shao Liwei, Zhou Xiaozhi, Cao Yutong, Zhang Kun, Wang Jiandong

Coal Geology & Exploration

Coal-based CO2 geological storage is an important way to reduce greenhouse gas emissions, but there is also a safety risk of underground CO2 leakage. In order to evaluate the safety of coal-based CO2 geological storage, the roof samples of No.3 coal seam in Hudi Coal Mine, southern Qinshui Basin were collected, and the changes of artificial fracture morphology, whole rock mineral composition and CO2 conductivity of columnar samples in "CO2-H2O-Rock" reaction were studied by simulation experiments. The results show that calcite vein dissolution, secondary mineral filling and external effective stress jointly affect …

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Variation Law And Influencing Mechanism Of Surface Movement Parameters In Shendong Mining Area, Zhou Tingting, Su Lijuan, Liu Hui, Zhu Xiaojun Jun 2021

Variation Law And Influencing Mechanism Of Surface Movement Parameters In Shendong Mining Area, Zhou Tingting, Su Lijuan, Liu Hui, Zhu Xiaojun

Coal Geology & Exploration

The mining areas in western China generally have the characteristics of large reserves, shallow depth and simple overlying rock structure, and mining activities in such areas have a significant impact on the surface. In order to study the variation law of surface deformation and rock movement parameters in Shendong Mining Area, the dynamic deformation of the surface was studied based on the measured data of working face 22201 of Daliuta Coal Mine. Then the relationship between surface movement parameters and geological mining conditions were obtained from the measured data of 18 working faces in Shendong Mining Area, and the influence …

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Targeted Processing Method For Seismic Data Of Karst Caves And Goafs In Nanchuan Area, Meng Qingli, Ren Junxing, Yang Fan Jun 2021

Targeted Processing Method For Seismic Data Of Karst Caves And Goafs In Nanchuan Area, Meng Qingli, Ren Junxing, Yang Fan

Coal Geology & Exploration

In order to solve the problem of poor imaging effect of near surface karst cave and goaf location seismic data in seismic exploration, this paper summarizes the frequency, energy and signal-to-noise ratio characteristics of seismic data in this area using forward modeling combined with actual data analysis. On this basis, a set of corresponding processing methods are proposed, including micro log constrained tomography static correction, weak signal extraction and compensation, pre-stack five dimensional data regularization and structure constrained grid tomography velocity modeling. Through the application in Nanchuan area, the signal-to-noise ratio and wave group continuity of seismic data are obviously …

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The Development Of A Single-Component Non-Cable Seismograph In Underground Coal Mines, Li Yuan Jun 2021

The Development Of A Single-Component Non-Cable Seismograph In Underground Coal Mines, Li Yuan

Coal Geology & Exploration

In-seam wave seismic exploration, featured in wide detection range and high accuracy, plays an increasingly important role in the refined exploration of coal geological structures. However, most seismic exploration equipment is bulky, with a large number of cables are laid in construction, leading to low efficiency and high construction cost. This seriously restricts the development of high-precision in-seam wave seismic exploration technology in underground coal mines. Based on the design concept of nodal seismograph, the moving coil geophone is integrated into a complete cavity with the acquisition and control circuit, the time precision keeping circuit and the power supply circuit. …

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The Application Of Pneumatic Directional Drilling Technology In Gas Pre-Drainage Of Strips In Soft Coal Seams, Zhang Jie Jun 2021

The Application Of Pneumatic Directional Drilling Technology In Gas Pre-Drainage Of Strips In Soft Coal Seams, Zhang Jie

Coal Geology & Exploration

It is costly and inefficient to drill through floor tunnel to eliminate outburst in soft coal roadway strip in Huaibei Mining Area. The bedding pneumatic directional borehole technology can accurately control the borehole trajectory in the strip coal seam according to the design, and realize the outburst elimination of the strip coal roadway through drilling gas extraction. Based on soft coal seam characteristics of the Huaibei Mining Area, the coal lane stripes drainage of gas in the directional hole design, selection of pneumatic directional drilling equipment, directional bore blastholes and shield technology, the evaluation of extraction effect are studied. The …

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Odu Professor Examines An Overlooked Source Of Coastal Water Quality, Tiffany Whitfield Jun 2021

Odu Professor Examines An Overlooked Source Of Coastal Water Quality, Tiffany Whitfield

News Items

No abstract provided.

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Table Of Contents, The Editors Jun 2021

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

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Analysis On The Deployment Of Mining Research Supported By The Grant Program Of Deep Resources Exploration And Mining, Fan Jun, Zhang Jialin, Qin Yuan, Wang Hao, Gao Yanan, Pei Yongzhi Jun 2021

Analysis On The Deployment Of Mining Research Supported By The Grant Program Of Deep Resources Exploration And Mining, Fan Jun, Zhang Jialin, Qin Yuan, Wang Hao, Gao Yanan, Pei Yongzhi

Coal Geology & Exploration

The Deep Resources Exploration and Mining(DREAM) grant program, within the framework of The National Key Research and Development Program grants, is a pillar to implement China’s science and technology strategy in the area of deep resources exploitation. To tackle the insufficient of theories and technologies for the 1000-meter-deep mining, a section of mining, covering the research of basic theories, general technologies and application demonstration, was arranged in the layout of DREAM under the principle of "whole chain design, integrated implementation". In the aspect of basic research, DREAM mainly focused on the deep rock mechanics and mining theory, such as the …

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Research On Green Coal Mining Strategy In Hedong Coalfield Based On Resource And Geological Environment Characteristic, Liu Hanbin, Cheng Fangqin Jun 2021

Research On Green Coal Mining Strategy In Hedong Coalfield Based On Resource And Geological Environment Characteristic, Liu Hanbin, Cheng Fangqin

Coal Geology & Exploration

Hedong Coalfield is located in the Loess Plateau of western Shanxi province at the western foot of the Lvliang Mountains in the middle reaches of the Yellow River. It is an important coking coal producing area, with severe soil erosion, fragile ecological environment, frequent occurrence of geological disasters and karst spring distribution in China. Through the analysis of resource and geological environment characteristics of Hedong Coalfield, it is found that the scarce coking coal reserves in Liliu mining area in the middle of the coalfield account for 70.8% of the total reserves. But its development intensity is higher than the …

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Occurrence Characteristics Of Carboniferous-Permian Tar-Rich Coal And Its Influencing Factors In Northern Shaanxi, Yao Zheng, Luo Qianzhou, Li Ning, Li Huabing, Wang Qiang, Gao Jun Jun 2021

Occurrence Characteristics Of Carboniferous-Permian Tar-Rich Coal And Its Influencing Factors In Northern Shaanxi, Yao Zheng, Luo Qianzhou, Li Ning, Li Huabing, Wang Qiang, Gao Jun

Coal Geology & Exploration

The rational development of tar-rich coal is of great significance to promote clean and efficient utilization of coal, improve the independent guarantee ability of oil and gas, and achieve carbon emission peak and carbon neutrality. In order to find out the occurrence characteristics of tar-rich coal in the typical mining areas of Carboniferous-Permian coalfield in Northern Shaanxi, based on coal exploration data and sample test results, this paper compares the tar yield of mineable coal seams, summarizes the spatial-temporal distribution rules of tar-rich coal, and discusses the occurrence influential factors. The results show that the average tar yield of mineable …

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Gas Drainage Borehole Completion Technology Of Directional Long Hole Drilling With Negative Angle, Ma Zan, Chen Dongdong, Xie Hengxing, Chen Tianzhu, Wang Bin, Jia Bingyi Jun 2021

Gas Drainage Borehole Completion Technology Of Directional Long Hole Drilling With Negative Angle, Ma Zan, Chen Dongdong, Xie Hengxing, Chen Tianzhu, Wang Bin, Jia Bingyi

Coal Geology & Exploration

Pre-drainage of coal seam gas with directional long boreholes is an effective technical means to achieve advanced control of coal mine gas area. Affected by mining deployment, negative-angle boreholes(downward holes) are widely used in production. Medium-hard coal seams have good porosity and usually do not require hole protection. However, the existing conventional methods can not effectively solve the problem of water accumulation in negative angle long boreholes. This paper takes the downward long boreholes in the No. 9 medium-hard coal seam of Longfeng Coal Mine in Guizhou as the research object. Two sets of directional long boreholes are constructed in …

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The Concealed Small Faults Detection Based On Gas Drainage Boreholes Along And Cross The Coal Seam, Xue Honglai, Wen Zhe Jun 2021

The Concealed Small Faults Detection Based On Gas Drainage Boreholes Along And Cross The Coal Seam, Xue Honglai, Wen Zhe

Coal Geology & Exploration

The faults have great influence on coal and gas outburst disasters, and accurate detection of faults location is very important to prevent such disasters. At present, large number of gas drainage boreholes were drilled in coal mines, but the geological information contained in these boreholes is not fully paid attention to, thus the method to detect concealed faults by gas-drainage boreholes was proposed. In this paper, by establishing a mathematical model for fault detection based on gas drainage drilling, a three-dimensional coordinate of fault planes and coal seam floors is calculated, and basic parameters such as fault location, drop, attitude …

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Quantitative Study Of 3d Numerical Simulation On Optimizing Borehole Layout Spacing Of Gas Drainage, Chen Yuexia, Chu Tingxiang, Chen Peng, Tang Yang Jun 2021

Quantitative Study Of 3d Numerical Simulation On Optimizing Borehole Layout Spacing Of Gas Drainage, Chen Yuexia, Chu Tingxiang, Chen Peng, Tang Yang

Coal Geology & Exploration

In order to optimize the spacing of boreholes and realize efficient drainage, based on the fluid solid coupling model, a three-dimensional geometric model was established to make it closer to the field reality, the gas drainage processes of a coal mine with different borehole spacing were simulated using COMSOL software. The results show that: the effective drainage area was visualized by the three-dimensional diagram of the isobaric surface with gas pressure of 0.74 MPa, and the influence of borehole spacing on the extraction efficiency was discussed. The results show that: the effective extraction radius is about 1.5 m during gas …

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An Advanced Co2 Gas-Phase Fracturing Technology For Efficient Methane Drainage, Outburst Prevention And Excavation In Outburst Coal Seam, Yang Baige, Zhang Junsheng, Linghu Jianshe, Cao Yunxing Jun 2021

An Advanced Co2 Gas-Phase Fracturing Technology For Efficient Methane Drainage, Outburst Prevention And Excavation In Outburst Coal Seam, Yang Baige, Zhang Junsheng, Linghu Jianshe, Cao Yunxing

Coal Geology & Exploration

Coal and gas outburst in coal mines is a serious disaster in China. Although the disaster has been reduced significantly over the past 10 years, vicious accidents still occure, causing serious losses to the lives of miners and the safety of coal mines. The current applied technologies for outburst prevention and control include hydraulic fracturing, hydraulic slitting, hydraulic flushing, deep hole blasting, intensive drilling, etc., which have solved the outburst problem and safe excavation in some degrees. Nevertheless, the above-mentioned technologies could not solve the problems of safety excavation in the high gas content and low permeability outburst coal seams. …

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The Origin Of Coal Measure Breccia In Jinggong No.3 Coal Mine, Pingshuo, Shanxi, Shi Yanqiang Jun 2021

The Origin Of Coal Measure Breccia In Jinggong No.3 Coal Mine, Pingshuo, Shanxi, Shi Yanqiang

Coal Geology & Exploration

The genesis and occurrence of coal measure breccia in Jinggong No.3 Coal Mine of Pingshuo are special and closely related to the coal seams. Through core observation of supplementary drilling, combined with regional geology and analysis of previous drilling data, the composition, structure and structural characteristics of breccia in the study area are described in detail, and the horizon, thickness and distribution of breccia are delineated. It is found that the composition of breccia in Jinggong No.3 Coal Mine of Pingshuo is complex, and the size of breccia is different. The maximum diameter of mudstone is more than 1.20 m, …

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Hydrate Reservoir Physical Properties Response And High-Pressure Gas-Water Reverse Penetration During Deepwater Oil And Gas Cementing, Zheng Mingming, Wang Xiaoyu, Zhou Kerui, Wang Kai, Wang Zhilin, Dong Gang, Wei Meng, Liu Tianle, Jia Dongyan Jun 2021

Hydrate Reservoir Physical Properties Response And High-Pressure Gas-Water Reverse Penetration During Deepwater Oil And Gas Cementing, Zheng Mingming, Wang Xiaoyu, Zhou Kerui, Wang Kai, Wang Zhilin, Dong Gang, Wei Meng, Liu Tianle, Jia Dongyan

Coal Geology & Exploration

Well cementing is an important stage during the process of energy extraction. When deep-water oil and gas cementing encounters hydrate formations, the hydration heat of cementing slurry will cause hydrate decomposition in the reservoir near the borehole wall and reverse penetration of high-pressure gas-water. To reduce and avoid the adverse effects of hydrate decomposition, it is critical to clarify the physical response of hydrate reservoirs and the law of high-pressure gas-water reverse penetration under different cementing conditions. In this paper, a two-dimensional cementing numerical model is established according to the SH2 exploration well of GMGS-1 project in Shenhu area in …

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Water Inrush Mechanism Of Thick Alluvium Aquifer With High Pressure Based On The “Bidirectional Fractures” Model In Huainan And Huaibei Mining Area, Liu Qimeng, Liu Yu, Xie Zhigang, Bai Hanying, Fu Xiang, Miao Changjun Jun 2021

Water Inrush Mechanism Of Thick Alluvium Aquifer With High Pressure Based On The “Bidirectional Fractures” Model In Huainan And Huaibei Mining Area, Liu Qimeng, Liu Yu, Xie Zhigang, Bai Hanying, Fu Xiang, Miao Changjun

Coal Geology & Exploration

The coal reserves under Quaternary thick alluvium with high pressure are huge in Huainan and Huaibei Mining Areas. In the process of increasing the upper limit mining near the alluvium, water inrush accidents often occur. However, it is difficult to reasonably explain the mechanism of such accidents by using the traditional aupper three zonesa theory. In this paper, the hydrogeological and engineering geological conditions of thick alluvium with high pressure are analyzed, and the abidirectional fracturesa model is established. Laboratory experiment, numerical simulation, theoretical analysis, and engineering application inspection are used to study the development law of downward infiltration zone …

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Surface Subsidence Control Technology Of Multi-Bed Separation Grouting, Ma Hewen Jun 2021

Surface Subsidence Control Technology Of Multi-Bed Separation Grouting, Ma Hewen

Coal Geology & Exploration

In order to enhance the injection ratio to meet the surface subsidence controlling requirements without obvious thick-and-hard strata in overburden for generating large-scale bed separation, the multi-bed separation grouting method is proposed in this paper. The scale model test is used to study the spatiotemporal evolution of overburden due to multi-bed separation grouting. The field measurements is proven that multi-bed separation grouting can successfully mitigate overburden failure and subsidence by increasing the boreholes number, and multi-bed separation grouting has successfully applied in Huaibei mining area. Filling masses with different diffusion radii are commonly formed in the different bed separation, which …

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