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Ichnofabrics and Their Environmental Interpretation from the Fluvial Deposits of the Middle Triassic Youfangzhuang Formation in Western Henan, Central China 被引量:6
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作者 Min Wang Yongan Qi +2 位作者 Da Li Mingyue Dai Yuguang Chang 《Journal of Earth Science》 SCIE CAS CSCD 2014年第4期648-661,共14页
Fluvial deposits from the Middle Triassic Youfangzhuang Formation in Henan Province, China contain a low-diversity trace fossils. Vertical dwelling burrows of opportunists dominate in active channel, whereas horizonta... Fluvial deposits from the Middle Triassic Youfangzhuang Formation in Henan Province, China contain a low-diversity trace fossils. Vertical dwelling burrows of opportunists dominate in active channel, whereas horizontal deposit-feeding, grazing, and vertical dwelling burrows occur in overbank deposits. Seven recurrent ichnofabrics were distingushed. The Palaeophycus tubularis ichnofabric pre- serves below scour interface between two fluvial cycles. The Skolithos linearis ichnofabric forms in middle to high-energy, soft substrates in the middle and upper parts of active channel deposits under semi-arid climate. The Skolithos linearis-Planolites montanus ichnofabric occurs in the sediments just a little above the Skolithos linearis ichnofabric and is formed in middle-energy, soft substrates in the up- per part of active channel deposits. The Planolites montanus ichnofabric is mostly preserved in associa- tion with medium- to thick-bedded brown-red silty mudstones or siltstones in low-energy, perennial muddy bottom ponds in overbank settings. The Taenidium barretti ichnofabric is interpreted as peri- odically exposed ephemeral ponds or low-energy distal floodplain. The Skolithos isp. ichnofabric com- monly occurs in middle to high-energy firm ground of proximal foodplain or crevasse-splay deposits. The root trace iehnofabric occurs in the crevasse splay deposits. The presence of thin palaeosols and the abundance of calcretization in mudstones indicate a seasonal climate ranging from humid to semi-arid, with high temperature, rainfall, and well-defined dry and wet seasons. 展开更多
关键词 trace fossil ICHNOFABRIC fluvial deposit environmental interpretation Middle Triassic Youfangzhuang Formation.
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Coal and gas outburst mechanism of the “Three Soft” coal seam in western Henan 被引量:10
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作者 LEI DongJi LI Chengwu +1 位作者 ZHANG Zimin ZHANG Yugui 《Mining Science and Technology》 EI CAS 2010年第5期712-717,共6页
Based on the particularities of gas outbursts,i.e.,low gas bearing capacity and low gas pressure in the "Three Soft" coal seam in western Henan,we applied the theories of plate tectonics and regional structu... Based on the particularities of gas outbursts,i.e.,low gas bearing capacity and low gas pressure in the "Three Soft" coal seam in western Henan,we applied the theories of plate tectonics and regional structural evolution to investigate the mechanism of this seam and its impact on the coal seam gas formation.Our investigation revealed that coal and gas outbursts are distributed in a strip in a NW direction,with a number of high-penetration mines scattered towards the south side and low-gas mines largely located on the north side.We analyzed the statistics of 38 gas explosions and the rock-coal sturdiness number coefficient f of 167 sampling sites in the region and found the gas outburst mechanism that features a "low indicator outburst phenomenon".The mechanism is characterized by structural coal as its core,a low gas bearing capacity,low gas pressure and sturdiness coefficient f mostly less than 0.3.Our research results provide a theoretical foundation for effective control of gas disasters. 展开更多
关键词 coal and gas outburst mechanism investigation THRESHOLD sliding structure
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Earthquake-induced Soft-sediment Deformation Structures in the Dengfeng Area,Henan Province,China:Constraints on Qinling Tectonic Evolution during the Early Cambrian 被引量:3
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作者 YANG Wentao WANG Min QI Yong'an 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第6期1835-1846,共12页
Soft-sediment deformation structures are abundant in the Cambrian Zhushadong and Mantou formations of the Dengfeng area, Henan Province, China. Soft-sediment deformation structures of the Zhushadong Formation consist ... Soft-sediment deformation structures are abundant in the Cambrian Zhushadong and Mantou formations of the Dengfeng area, Henan Province, China. Soft-sediment deformation structures of the Zhushadong Formation consist of fluidized deformation, synsedimentary faults, seismo-folds and plastic deformation; the Mantou Formation is dominated by small-scale horst faults, intruded dikes, fluidized veins, and seismo-cracks. These structures are demonstrated to be earthquake-related by analysis of trigger mechanisms, and may indicate the activity of the Qinling tectonic belt during the early Cambrian. Furthermore, the assemblages of soft-sediment deformation structures altered with time: large-scale, intense deformation in the Zhushadong Formation alters to small-scale, weak deformation in the Mantou Formation. This striking feature may have been caused by changes in hypocentral depth from deep-focus to shallow-focus earthquakes, indicating that the Qinling tectonic belt developed from the subduction of the Shangdan Ocean to the extension of the Erlangping back-arc basin. This study suggests that soft-sediment deformation structures can be used to reveal the activity of a tectonic belt, and, more importantly, changes in deformation assemblages can track the evolution of a tectonic belt. 展开更多
关键词 soft-sediment deformation structures SEISMITES Qinling tectonic belt Cambrian Southern North China Block
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Evolution of a hydrodynamic field and its effect on hydrocarbon accumulation in the Biyang depression, Henan province 被引量:2
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作者 FU Yong DONG Qing-hong +1 位作者 BAI Zhen-rui WANG Wan-jun 《Journal of China University of Mining and Technology》 EI 2008年第4期599-605,共7页
The hydro-geologic stages in the Biyang Depression, Henan Province, were defined and factors controlling the evolution of the hydrodynamic field in this area were analyzed. The evolution of the paleo-hydrodynamic fiel... The hydro-geologic stages in the Biyang Depression, Henan Province, were defined and factors controlling the evolution of the hydrodynamic field in this area were analyzed. The evolution of the paleo-hydrodynamic field was studied by using the method of sedimentary-water-head and the changing patterns of the present hydrodynamic field as determined from measured pressure data. The results show that the evolution of the hydrodynamic field is one of inheritance and that it controls hydrocarbon accumulation. The deposition center in the southeast of the depression is always a high-value zone for water-head and a dynamic- source zone of the hydrodynamic field. The slope zone in the northwest of the depression is always a low-value zone for water-head and is the main discharge area for groundwater; this is the hydrocarbon accumulation zone. Hydrocarbon accumulation is controlled by the hydrodynamic field. The reservoir shows a ring-shaped horizontal pattern. Accumulation occurs in a pressure equilibrium zone at the frontal surface between sedimentary water and infiltrating water. The hydrocarbon accumulations occur in two vertically different discharge units, Eh31 and Eh32, under the action of overpressure. 展开更多
关键词 Biyang depression hydrodynamic field hydrocarbon accumulation pressure equilibrium zone discharge unit
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Study on Balanced Development of Industrialization,Urbanization and Agricultural Modernization in Henan Province 被引量:1
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作者 LI Hai-yu 《Asian Agricultural Research》 2012年第2期9-14,共6页
This article expounds the connotation of balanced development of " industrialization,urbanization and agricultural modernization",and points out the problems thwarting balanced development of " industri... This article expounds the connotation of balanced development of " industrialization,urbanization and agricultural modernization",and points out the problems thwarting balanced development of " industrialization,urbanization and agricultural modernization" in Henan Province as follows:the level of industrialization is not high;the general level of urbanization is low;the agricultural foundation is weak and there are many institutional barriers.The goal of balanced development of " industrialization,urbanization and agricultural modernization" in Henan Province is to take a road of industrialization and urbanization,not at the expense of agriculture and food.Based on this,the measures are put forward for balanced development of " industrialization,urbanization and agricultural modernization " in Henan Province as follows:keep to the new road of industrialization with characteristics of Henan Province,promote the development of industry and accelerate the transformation of pattern;keep to the road of new urbanization with characteristics of Henan Province,and promote the rapid change in urban development pattern;adhere to the road of agricultural modernization with characteristics of Henan Province,and promote the rapid change in pattern of agricultural development. 展开更多
关键词 Henan Province INDUSTRIALIZATION URBANIZATION Agricultural modernization Balanced development
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Evaluation of Social Vulnerability to Natural Disasters on a County Scale in Henan Province
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作者 Shanfeng HE Liping DU Xiuhua GAO 《Asian Agricultural Research》 2016年第3期27-31,35,共6页
Social vulnerability evaluation is of important significance to analyzing risks of natural disasters to human society and economy. By using expert investigation and AHP method,12 indicators from four aspects( populati... Social vulnerability evaluation is of important significance to analyzing risks of natural disasters to human society and economy. By using expert investigation and AHP method,12 indicators from four aspects( population,economy,infrastructure and disaster prevention and mitigation capacity) are selected to assess social vulnerability to natural disasters on a county scale in Henan Province. The results show that the population vulnerability and economic vulnerability to natural disasters in the eastern region is generally higher than in the western region,while the areas with high infrastructure vulnerability are mainly located in the northwest; the disaster prevention and mitigation capacity in northwest is higher than in east and south,and this capacity of various districts is obviously higher than that of counties; in terms of the spatial pattern,social vulnerability to natural disasters is roughly higher in a belt from northeast to southwest,and lower on both sides of the belt. The results can provide scientific basis for disaster risk management and disaster prevention and mitigation planning in Henan Province. 展开更多
关键词 Social VULNERABILITY DISASTER prevention and mitigation ability COUNTY SCALE HENAN Province
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Study on the Spatiotemporal Pattern Evolution and Influencing Factors of Population Aging in Henan Province
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作者 LIU Dingming DU Jiusheng +1 位作者 WANG Yu YANG Junping 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第2期80-94,共15页
This study utilized census data from Henan Province for the years 2000,2010,and 2020 to investigate the spatiotemporal evolution of population aging,defined by the proportion of the population aged 65 and above.Employ... This study utilized census data from Henan Province for the years 2000,2010,and 2020 to investigate the spatiotemporal evolution of population aging,defined by the proportion of the population aged 65 and above.Employing spatial analysis techniques such as spatial autocorrelation and the standard deviation ellipse,the research mapped out the progression and distribution of aging demographics.Furthermore,the study delved into the influencing factors of aging using an optimal parameters-based geographical detector.Results indicate a deepening degree of population aging in Henan Province,transitioning from an adult type to an old type structure.There is a marked positive spatial correlation among counties,with high-value aging areas initially decreasing,then increasing,and notably spreading from the central to the central and southern regions of the province.The center of gravity for population aging,specifically around Changge City and Xuchang City,exhibits a trajectory moving southeast before shifting northwest.Factor detection reveals that in 2000,2010,and 2020,the elderly dependency ratio predominantly influences the aging trend,with explanatory powers of 88.4%,87.9%,and 90.9%,respectively.Interaction analysis indicates that the interaction between the old-child ratio and the elderly dependency ratio has a strong explanatory power for the aging patterns in Henan Province,reaching 97.3%,97.0%,and 97.4%,respectively. 展开更多
关键词 population aging spatial pattern evolution spatial autocorrelation influencing factors optimal parameters-based geographical detector
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Crystal Structure of a Ternary Copper(Ⅱ) Complex of N,N'-(p-Xylylene)dialanine Acid and 1,10-Phenanthroline
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作者 贾磊 徐君 +3 位作者 郝忠言 陈龙海 成飞翔 唐宁 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第8期1270-1274,共5页
The compound [Cu2(bpy)2(PDIAla)(H2O)2](ClO4)2·H2O(H2PDIAla = N,N'-(p-xylylene)dialanine,bipy = 2,2'-bipyridine) 1 has been synthesized and structurally determined by single-crystal X-ray diffraction... The compound [Cu2(bpy)2(PDIAla)(H2O)2](ClO4)2·H2O(H2PDIAla = N,N'-(p-xylylene)dialanine,bipy = 2,2'-bipyridine) 1 has been synthesized and structurally determined by single-crystal X-ray diffraction,elemental analyses and IR spectroscopy.The crystal belongs to the monoclinic system,space group P21 with a = 10.9772(6),b = 18.5464(9),c = 11.0790(6) ,β = 116.3110o,V = 2021.87(18) 3,Z = 2,Dc = 1.594 Mg/m3,Mr = 970.70,μ = 1.260 mm-1,F(000) = 996,λ(MoKα) = 0.71073 ,the final R = 0.0400 and wR = 0.1050 for all observed reflections.In the structure,the O(5)-H(52)…O(4) hydrogen bonding between aqua ligand and carbonyl oxygen of the H2PDIAla ligand along the c axis produce hydrogen-bonded helices which are assembled along the b axis through O(61)-H(61)…O(2) and N(6)-H(6N)…O(2) interactions to form 2-D layers that are further linked by π···π interactions between bpy ligands to yield a three-dimensional supramolecular network. 展开更多
关键词 copper(Ⅱ) complex hydrogen-bonded helices π···π interactions crystal structure
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Analysis on safety production in coal mines Henan Province
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作者 孔留安 张文勇 《Journal of Coal Science & Engineering(China)》 2006年第1期82-85,共4页
Based on the rigorous situation of safety production in coal mines, the paper analyzed the statistical data of recent accidents indexes in Henan's coal mines. Using investigation and comparison analysis methods, a... Based on the rigorous situation of safety production in coal mines, the paper analyzed the statistical data of recent accidents indexes in Henan's coal mines. Using investigation and comparison analysis methods, a specified analysis on mining conditions,technical facility level, safety input and vocational quality of workers in Henan's coal mines was conducted. The result indicates that there have been existing such main safety production problems as weak safety management, low-level facilities, inadequate safety input and poor vocational quality and so on. Finally it proposes such reference solutions as to establish and perfect coal mining supervision and management system, to increase safety investment into techniques and facilities and to strengthen workers' safety education and introduction of more high-level professional talents. 展开更多
关键词 coal mine safety safety management safety input
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Study on Carbon Emission Driving Factors and Low-carbon Policy of Transportation Industry in Henan Province
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作者 LIU Zhan-yu SUN Xia-ling 《International Journal of Plant Engineering and Management》 2018年第1期32-37,共6页
The transportation industry is the basic industry of national economic development. At the same time, it is the only industry in China that has continuously increased CO2 emissions, and the high energy consumption pro... The transportation industry is the basic industry of national economic development. At the same time, it is the only industry in China that has continuously increased CO2 emissions, and the high energy consumption problems have not been solved. Henan province, as a major energy consumption province, it is urgent to improve the supply quality of transportation industry. The paper uses the IPCC calculation method for carbon emission to calculate the CO2 emissions of transportation industry in Henan province from 2004 to 2014. Then, this paper uses the LMDI method to decompose the CO2 emission in the transportation industry and give the proposal to reduce the CO2 emission according to the CO2 emission drivers. 展开更多
关键词 transportation industry CO2 emissions driving factors low-carbon policy
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Towards carbon neutrality: A comprehensive study on the utilization and resource recovery of coal-based solid wastes 被引量:2
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作者 Zhiguo Zhang Cui Xu +1 位作者 Gan Cheng Ee Von Lau 《International Journal of Coal Science & Technology》 2025年第3期1-24,共24页
Coal-based soild wastes(CBSWs)are industrial byproducts that can be harmful to the environment.The exploitation and utilization of CBsWs offer societal advantages such as resource conservation,pollution reduction,and ... Coal-based soild wastes(CBSWs)are industrial byproducts that can be harmful to the environment.The exploitation and utilization of CBsWs offer societal advantages such as resource conservation,pollution reduction,and cost-effective production.However,environmentally sustainable management remains a worldwide challenge due to the substantial production volume and limited disposal capacity of CBSWs.The physicochemical properties and utilization of CBSWs are summarized,including fly ash,coal gangue and coal gasification slag.It also presents the current global applications status of CBSWs resources and examines market supply and demand.Subsequently,the paper provides an overview of studies on ways to utilise CBSWs,highlighting the primary avenues of CBSWs resource utilization which are mainly from the fields of chemical materials,metallurgy and agriculture.Furthermore,a comparative evaluation of the various methods for CBSWs resource recovery is conducted,outlining their respective advantages and disadvantages.The future development of CBSWs recycling processes is also discussed.The review concludes that while there is a growing need for attention in CBSWs recycling,its utilization will involve a combination of both large-scale treatment and refinement processes.The paper aims to offer references and insights for the effective utilization and environmental protection of CBSWs.Future direction will focus on the collaborative utilization of CBSWs,emphasizing on the combination of large-scale and high-value utilization.In addition,there is a need to establish a comprehensive database based on on-site production practices,explore on-site solutions to reduce transportation costs,and improve physicochemical properties during the production process. 展开更多
关键词 Coal-based solid wastes(CBSWs) High-value utilization Carbon neutrality MATERIALS
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Investigation on coal damage and fracture extension law of liquid nitrogen injection pre-cooling and fracturing under true triaxial stress 被引量:1
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作者 Botao Li Haifei Lin +7 位作者 Jianping Wei Hongtu Zhang Shugang Li Zongyong Wei Lei Qin Pei Wang Rongwei Luo Zeran Liu 《International Journal of Mining Science and Technology》 2025年第2期213-229,共17页
To more accurately describe the coal damage and fracture evolution law during liquid nitrogen(LN_(2))fracturing under true triaxial stress,a thermal-hydraulic-mechanical-damage(THMD)coupling model for LN_(2) fracturin... To more accurately describe the coal damage and fracture evolution law during liquid nitrogen(LN_(2))fracturing under true triaxial stress,a thermal-hydraulic-mechanical-damage(THMD)coupling model for LN_(2) fracturing coal was developed,considering the coal heterogeneity and thermophysical parameters of nitrogen.The accuracy and applicability of model were verified by comparing with LN_(2) injection pre-cooling and fracturing experimental data.The effects of different pre-cooling times and horizontal stress ratios on coal damage evolution,permeability,temperature distribution,and fracture characteristics were analyzed.The results show that the permeability and damage of the coal increase exponentially,while the temperature decreases exponentially during the fracturing process.As the pre-cooling time increases,the damage range of the coal expands,and the fracture propagation becomes more pronounced.The initiation pressure and rupture pressure decrease and tend to stabilize with longer precooling times.As the horizontal stress ratio increases,fractures preferentially extend along the direction of maximum horizontal principal stress,leading to a significant decrease in both initiation and rupture pressures.At a horizontal stress ratio of 3,the initiation pressure drops by 48.07%,and the rupture pressure decreases by 41.36%.The results provide a theoretical basis for optimizing LN_(2) fracturing techniques and improving coal seam modification. 展开更多
关键词 Liquid nitrogen fracturing Thermal–hydraulic-mechanical-damage coupling Heterogeneous coal True triaxial stress Fracture morphology
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Hydraulic fracture propagation in soft coal composite reservoirs:Mechanical responses and energy dissipation mechanisms 被引量:1
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作者 Aitao Zhou Yizheng He +3 位作者 Kai Wang Bo Li Yida Wang Yuexin Yang 《International Journal of Mining Science and Technology》 2025年第4期573-588,共16页
The hydraulic fractures induced in soft coal composite reservoirs have complex extension and energy evolution characteristics.In this study,the mechanism whereby gas outbursts can be eliminated by hydraulic fracturing... The hydraulic fractures induced in soft coal composite reservoirs have complex extension and energy evolution characteristics.In this study,the mechanism whereby gas outbursts can be eliminated by hydraulic fracturing was revealed.The combined fracturing process of a coal seam and its roof under different in situ stress and fracture spacing conditions was analysed through true triaxial physical tests and numerical simulations.The results showed that the pre-fracturing of the roof had a pressure relief effect on the coal seam,and the secondary pressure relief of the coal seam could be completed at a lower fracture initiation pressure.To ensure the continued presence of the stress shadow effect in actual projects,the fracture spacing should be maintained within the critical range influencing the fracture extension.If the vertical stress is high,a call on increasing the fracture spacing can be taken;otherwise,it must be reduced.In the early phase of fracturing,energy is mostly concentrated at the tip and surface of the fracture;however,the proportion of surface energy for subsequent fracturing is gradually reduced,and the energy is mostly used to open the formation and work on the surrounding matrix.Hydraulic fracturing creates new fractures to interconnect originally heterogeneously distributed gas zones,enabling the entire coal seam to first establish interconnected pressure equilibration,then undergo gradientcontrolled depressurization.Hydraulic fracturing can homogenize the stress field and gas pressure field in the original coal seam via communication pressure equalization and reduction decompression,reduce the elastic and extension energies,increase the minimum failure energy required for instability;and realize the elimination of gas outbursts.Our findings provide some theoretical support for the efficient development of coalbed methane and the prevention and control of dynamic gas disasters in coal mines. 展开更多
关键词 Coal-rock complex Soft coal seams Hydraulic fracturing Energy evolution Eliminating gas outburst
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Time effect of elastic energy release of surrounding rock and evaluation method of reasonable advancing speed 被引量:1
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作者 Ruifu Yuan Qi Ma +3 位作者 Qunlei Zhang Chun Feng Chunfu Wei Yan Gao 《International Journal of Coal Science & Technology》 2025年第1期113-124,共12页
To reveal the rock burst mechanism,the stress and failure characteristics of coal-rock strata under different advancing speeds of mining working face were explored by theoretical analysis,simulation,and engineering mo... To reveal the rock burst mechanism,the stress and failure characteristics of coal-rock strata under different advancing speeds of mining working face were explored by theoretical analysis,simulation,and engineering monitoring.The relationship between energy accumulation and release was analyzed,and a reasonable mining speed according to specific projects was recommended.The theoretical analysis shows that as the mining speed increases from 4 to 15 m/d,the rheological coefficient of coal mass ranges from 0.9 to 0.4,and the elastic energy of coal mass accumulation varies from 100 to 900 kJ.Based on the simulation,there is a critical advancing speed,the iteration numbers of simulation are less than 15,000 per mining 10 m coal seam,the overburden structure is obvious,the abutment pressure in coal mass is large,and the accumulated energy is large,which is easy to cause strong rock burst.When the iteration number is greater than 15,000,the static force of coal mass increases slightly,but there is no obvious rock burst.Based on engineering monitoring,the mining speed of a mine is less than 8 m/d,and the periodic weighting distance is about 17 m;as the mining speed is greater than 10 m/d,and the periodic weighting distance is greater than 20 m;as the mining speed is 3-8 m/d,and the range of high stress in surrounding rock is 48 m;as the advancing speed is 8-12 m/d,and the high-stress range in surrounding rock is 80 m.Moreover,as the mining speed is less than 8 cut cycles,the micro seismic energy is less than 10,000 J;as the mining speed is 12 cut cycles,the microseismic energy is about 20,000 J.In summary,the advancing speed is positively correlated with the micro seismic event;as the mining speed increases,the accumulated elastic energy of surrounding rock is greater,which is easy to cause rock burst.The comprehensive analysis indicates the daily advance speed of the mine is not more than 12 cut cycles. 展开更多
关键词 Mining speed Rock burst Engineering analysis Simulation Coal-rock stress
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Effectively enhanced catalytic effect of sulfur doped Ti_(3)C_(2)on the kinetics and cyclic stability of hydrogen storage in MgH_(2) 被引量:1
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作者 Zhenluo Yuan Xiuxiu Zhang +7 位作者 Yitian Wu Shuyan Guan Shiqian Zhao Liqiang Ji Qiuming Peng Shumin Han Yanping Fan Baozhong Liu 《Journal of Magnesium and Alloys》 2025年第4期1843-1853,共11页
Designing catalysts with high catalytic activity and stability is the key to achieve the commercial application of MgH_(2).Herein,the sulfur doped Ti_(3)C_(2)(S-Ti_(3)C_(2))was successfully prepared by heat treatment ... Designing catalysts with high catalytic activity and stability is the key to achieve the commercial application of MgH_(2).Herein,the sulfur doped Ti_(3)C_(2)(S-Ti_(3)C_(2))was successfully prepared by heat treatment of Ti_(3)C_(2)MXene under Ar/H_(2)S atmosphere to facilitate the hydrogen release and uptake from MgH_(2).The S-Ti_(3)C_(2)exhibited pleasant catalytic effect on the hydriding/dehydriding kinetics and cyclic stability of MgH_(2).The addition of 5 wt%S-Ti_(3)C_(2)into MgH_(2)resulted in a reduction of 114℃in the starting dehydriding temperature compared to pure MgH_(2).MgH_(2)+5 wt%S-Ti_(3)C_(2)sample could quickly release 6.6 wt%hydrogen in 17 min at 220℃,and 6.8 wt%H_(2)was absorbed in 25 min at 200℃.Cyclic testing revealed that MgH_(2)+5 wt%S-Ti_(3)C_(2)system achieved a reversible hydrogen capacity of 6.5 wt%.Characterization analysis demonstrated that Ti-species(Ti0,Ti^(2+),Ti-S,and Ti^(3+))as active species significantly lowered the dehydrogenation temperature and promoted the re-/dehydrogenation kinetics of MgH_(2),and sulfur doping can effectively improve the stability of Ti0 and Ti^(3+),contributing to the improvement of cyclic stability of MgH_(2).This study provides strategy for the construction of catalysts for hydrogen storage materials. 展开更多
关键词 Hydrogen storage MgH_(2) KINETICS Cyclic stability
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Evolution law of pulsating seepage and thermal deformation by injecting high-temperature steam into coal for thermal coalbed methane recovery
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作者 Zhiqiang Li Junliang Li +7 位作者 Jinsheng Chen Ali Karrech Ningchao Zhang Ju Chang Kaiqi Jin Yangyang Yu Hongbin Wang Aijie Wang 《Deep Underground Science and Engineering》 2025年第1期119-131,共13页
Chinese coal reservoirs are characterized by low pressure and low permeability,which need to be enhanced so as to increase production.However,conventional methods for permeability enhancement can only increase the per... Chinese coal reservoirs are characterized by low pressure and low permeability,which need to be enhanced so as to increase production.However,conventional methods for permeability enhancement can only increase the permeability in fractures,but not the ultra-low permeability in coal matrices.Attempts to enhance such impermeable structures lead to rapid attenuation of gas production,especially in the late stage of gas extraction.Thermal stimulation by injecting high-temperature steam is a promising method to increase gas production.The critical scientific challenges that still hinder its widespread application are related to the evolution law of permeability of high-temperature steam in coal and the thermal deformation of coal.In this study,an experimental approach is developed to explore the high-temperature steam seepage coupled with the thermal deformation in coal under triaxial stress.The tests were conducted using cylindrical coal specimens of?50 mm×100 mm.The permeability and thermal strain in coal were investigated when high-temperature steam was injected at151.11,183.20,213.65,and 239.76°C.The experimental results reveal for the first time that as the amount of injected fluid increases,the steam permeability shows periodic pulsation changes.This paper introduces and explains the main traits of this discovery that may shed more light on the seepage phenomenon.When the injected steam temperature increases,the amplitude of pulsating permeability decreases,whereas the frequency increases;meanwhile,the period becomes shorter,the pulsation peak appears earlier,and the stabilization time becomes longer.The average peak permeability shows a“U-shaped”trend,decreasing first and then increasing as the steam temperature increases.Meanwhile,with the extension of steam injection time,the axial,radial,and volumetric strains of coal show a stage-wise expansion characteristic at different temperatures of steam injection,except for the radial strains at 151.11°C.A two-phase flow theory of gas–liquid is adopted to elucidate the mechanism of pulsating seepage of steam.Moreover,the influencing mechanism of inward and outward thermal expansion on the permeability of coal is interpreted.The results presented in this paper provide new insight into the feasibility of thermal gas recovery by steam injection. 展开更多
关键词 coalbed methane PERMEABILITY PULSATION STEAM thermal deformation two-phase flow
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FSS-YOLO:The Lightweight Drill Pipe Detection Method Based on YOLOv8n-obb
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作者 Mingyang Zhao Xiaojun Li +1 位作者 Miao Li Bangbang Mu 《Computers, Materials & Continua》 2025年第8期2827-2846,共20页
The control of gas extraction in coal mines relies on the effectiveness of gas extraction.The main method of gas extraction is to drive drill pipes into the coal seam through a drilling rig and use technologies such a... The control of gas extraction in coal mines relies on the effectiveness of gas extraction.The main method of gas extraction is to drive drill pipes into the coal seam through a drilling rig and use technologies such as hydraulic fracturing to pre-extract gas in the drill holes.Therefore,the real-time detection of the drill pipe status is closely related to the effectiveness of gas extraction.To achieve fast and accurate identification of drill pipes,we propose FSSYOLO,which is a lightweight drill pipe detection method based on YOLOv8n-obb.This method first introduces the FasterBlock module into the C2f module of YOLOv8n-obb to reduce the number of model parameters and decrease the computational cost of the model and redundant feature maps.Next,the SimAM attention mechanism is added to the backbone network to enhance the weight of important features in the feature map and improve the model’s feature extraction capability.In addition,using shared convolution to optimize the detection head,not only lightens the detection head but also enhances its ability to learn features of different scales,improving the model’s generalization ability.Finally,the FSS-YOLO algorithm is validated on the self-built dataset.The results show that compared with the original algorithm,FSS-YOLO achieves improvements of 5.1%in mAP50 and 11.5%in Recall,reduces the number of parameters by 45.8%,and achieves an inference speed of 27.8 ms/frame on Jetson Orin NX.Additionally,the visual detection results for different scenarios demonstrate that the improved YOLOv8n-obb algorithm has promising application prospects. 展开更多
关键词 Gas extraction YOLOv8n-obb SimAM shared Conv coal mine intelligent coal mine
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Sequence stratigraphy and sedimentary evolution from Late Cretaceous to Quaternary in the Romney 3D seismic area,deep-water Taranaki Basin(New Zealand)
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作者 Guang-Xu Wang Wei Wu +4 位作者 Quan Li Wei-Qing Liu Yong-Sheng Zhou Shi-Qin Liang Ya-Ping Sui 《Petroleum Science》 2025年第5期1854-1875,共22页
The study of sequence stratigraphy often focuses on shallow marine and shelf-edge regions,while research on deep-sea stratigraphic sequences remains relatively weak.This study,based on highresolution 3D seismic data a... The study of sequence stratigraphy often focuses on shallow marine and shelf-edge regions,while research on deep-sea stratigraphic sequences remains relatively weak.This study,based on highresolution 3D seismic data and drilling information,utilized sequence stratigraphy and seismic sedimentology as guidelines,and employed seismic interpretation methods to performed a division of deepsea stratigraphic sequences within the Romney 3D seismic survey area in the deep-water Taranaki Basin,New Zealand.Furthermore,it analyzed the characteristics of typical depositional systems and their associated controlling factors.The findings are as follows:(1)Based on seismic reflection termination relationships and seismic facies characteristics,four second-order sequence boundaries and nine thirdorder sequence boundaries were identified,resulting in the delineation of three second-order sequences and twelve third-order sequences in the basin.(2)Five seismic facies were recognized,corresponding to five typical sedimentary bodies:mass transport deposits(MTDs),deep-water channel,levee deposits,deltaic deposits,and pelagic deposits.However,due to the relatively thin sedimentary thickness of carbonate sediments,the seismic facies characteristics of carbonate sediments cannot be discerned in seismic data,but can be identified based on well data.Deltaic sediments mainly developed during the rift stage of the basin,while carbonate sediments formed during the transition from a passive to an active margin.Deep-water channel and levee deposits and MTDs emerged during the active margin stage,while pelagic deposits are ubiquitous in marine environments.(3)The uplift of New Zealand's interior and climate-driven erosion caused the resurgence of clastic sediments,which began to be transported to the deep sea,the seafloor topography would directly affect the movement path of sediment gravity flow,and sediment supply can affect the development and evolution of sedimentary systems.(4)Event deposits boundaries,such as erosional scour surfaces formed by channels and unconformities created by MTDs,can serve as boundaries for the division of deep-water stratigraphic sequences.This study proposes a method for delineating deep-water stratigraphic sequences using event deposits,particularly suitable under conditions where the influence of relative sea-level changes on deep-water deposits is relatively weak.This research not only enhances the understanding of deep-water depositional sequences but also provides a reference for studies on the evolution of deep-water deposition and its controlling factors in research areas with similar geological backgrounds worldwide. 展开更多
关键词 Sequence stratigraphy Seismicfacies Sedimentary systemevolution Genesismechanism Sedimentsupply Deep-water Taranaki Basin
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Stress Waves Propagation Along the Frictional Interface with a Micro-contact
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作者 Lingyan Shen Yonggui Liu +2 位作者 Keyan Li Xiaofei Ji Xiangyu Jin 《Acta Mechanica Solida Sinica》 2025年第1期152-165,共14页
The stress wave profile at the frictional interface is crucial for investigating the frictional process.This study modeled a brittle material interface with a micro-contact to analyze the fine stress wave structure as... The stress wave profile at the frictional interface is crucial for investigating the frictional process.This study modeled a brittle material interface with a micro-contact to analyze the fine stress wave structure associated with frictional slip.Employing the finite element simulation alongside the related wave theory and experiments,two new wave structures were indentified:A Mach cone symmetric to the frictional interface associated with incident plane wave propagation,and a new plane longitudinal wave generated across the entire frictional interface at the moment when the incident wave began to propagate.The time and space of its appearance implies that the overall response of the frictional interface precedes the local wave response of the medium.Consequently,a model involving characteristic line theory and the idea of Green’s function has been proposed for its occurrence.The analysis results show that these two new wave phenomena are independent of the fracture of micro-contacts at the interface;instead,the frictional interface effect may be responsible for the generation of such new wave structures.The measured wave profiles provide a proof for the existence of the new wave structures.These results display new wave phenomena,and suggest a wave profile for investigating the dynamic mechanical properties of the frictional interface. 展开更多
关键词 Frictional interface Mach cone New wave Interaction FRACTURE
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Community Perception of Amenities in Tourism-oriented Traditional Villages
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作者 LI Luna YAN Haiyan 《Journal of Landscape Research》 2025年第3期77-80,共4页
Exploring the creation of comfortable objects in traditional tourism villages from the perspective of tourists can help reveal the essence of these amenities.Taking Yidoushui Ancient Village in Jiaozuo City,Henan Prov... Exploring the creation of comfortable objects in traditional tourism villages from the perspective of tourists can help reveal the essence of these amenities.Taking Yidoushui Ancient Village in Jiaozuo City,Henan Province as an example,this study applied the five-element theory of rural amenities to the research on the tourism-oriented traditional villages.With the help of text analysis tools and field investigations,it identified the objects,indicators,and elements of amenities in Yidoushui Ancient Village.Based on this framework,a survey questionnaire was designed for field research,followed by data analysis.The results indicated that tourists primarily focused on ecological amenities in traditional tourism villages;overall,visitors exhibited relative high perception and positive evaluation of the amenities;there were significant differences in the impact of different amenities indicators on tourist experience,and multiple indicators of ecological amenities showed significantly positive correlation with tourists’mood,satisfaction,and revisit intention,making them core factors in enhancing tourist experience.Cultural amenities significantly improved mood and satisfaction,but showed no significant effect on revisit intention. 展开更多
关键词 Rural amenities Rural tourism Yidoushui Village Rural development Tourist perception
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