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Propagating Characteristic of Premixed Methane-Oxygen Deflagration in the Coal Mine Lane Including a Refuge Chamber

Journal of Beijing Institute of Technology 2018年第1期27卷 109-117页

作者： Huanjuan Zhao Yiran Yan Yinghua Zhang yukun gao Mine Emergency Technology Research Center(University of Science and Technology Beijing) State Administration of Production Safety Supervision and Administration School of Civil and Resources Engineering University of Science and Technology Beijing Beijing 100083 China State Key Laboratory of High-Efficient Mining and Safety of Metal Mines ( University of Science and Technology Beijing) Ministry of Education Beijing 100083 China

In order to investigate detonation propagation and distribution problems of premixed CH_4 ＋ 2O_2 mixture around a concrete structure such as a refuge chamber,detonation experiments in one small size tube were conducted. A simulation method was developed to obtain the flow field load distribution in the coal mine lane and pressure load of each part for the refuge chamber. Firstly,a physical model of a full-size explosiontest lane was established,which included the refuge chamber. With the calculations of the exact initial detonation pressure,the propagation characteristics of CH_4 ＋ 2O_2 premixed mixture detonation in the lane was simulated. Simulation results of various parts from AUTODYN are recorded,and the shock wave arrival time and the pressure peak can be observed from the detonation pressure-time curve over the changing propagation distance. So curve differences in different locations cannot be ignored. Then by detonation experiments in the small size tube,detonation pressure-time curves and velocity were obtained. Finally the simulation waveform of variation curve agreed well with the experimental results,which validated the detonation simulation method. The difference between shockwaves of the two sensors confirmed that detonation wave changed along with distance and time. These results should be taken into serious consideration for the detonation progration and distribution problem in future researches.

关键词： mechanics of explosion detonation experiments physical model of the coal mine lane premixed methane-oxygen explosion refuge chamber

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Coal and gas outburst prevention using new high water content cement slurry for injection into the coal seam

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International Journal of Mining Science and Technology 2017年第4期27卷 669-673页

作者： Zhou Peiling Zhang Yinghua Huang Zhi'an gao yukun Wang Hui Luo Qiang State Key Laboratory of High-Efficient Mining and Safety of Metal Mines University of Science and Technology Beijing Ministry of Education

As coal and gas outburst is one of the most serious mine disasters, it is very important to at least control it if not prevent it from occurring. Injecting cement slurry or grouting into the coal seam can strengthen the seam, increase its rigidity coefficient(f), and reduce the volumetric expansion due to gas energy *** paper reports the results of laboratory experiments on cement-based high water content slurry having different water-cement ratios(W/C) to be used for coal injection. The results show that as the W/C increases, the mobility of the slurry and its setting time increase. The compressive strength and rupture strength, however, are reduced. Furthermore, high W/C grout shows early strength after 7 days, which can be 80% of its 14-day compressive strength. To achieve rapid setting and early strength, the addition of Na_2SiO_3has proven to give the best result, when the concentration of the additive is 3%. The initial and final setting times are 13 and 21 min shorter than samples without Na_2SiO_3, while the compressive strength is more than double. As a retarder, the initial setting time can be extended to 83 min when tartaric acid of 0.4% concentration is added. Through the orthogonal experiment, the optimum recipe of the new high water content slurry has been determined to be: W/C = 2, tartaric acid = 0.2%, Na_2SiO_3= 3%, and12% bentonite. Reinforcement by injection simulation experiments show that the grouting radius of the new slurry mix is 250 mm when the applied grouting pressure is 60 k Pa, 7-day rupture strength and compressive strength are 5.2 and 6.4 MPa, respectively, and are 37% and 88% higher than ordinary cement grout. It can be concluded that the newly developed slurry mix is more effective than the ordinary mix for reinforcing coal and controlling gas outburst.

关键词： Gas outburst Setting liquid Reinforce coal High-water solidified materials Rapid setting and early strength cement Retarder

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A High-OrderDiscontinuous GalerkinMethod for the Two-Dimensional Time-Domain Maxwell’s Equations on Curved Mesh

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Advances in Applied Mathematics and Mechanics 2016年第1期8卷 104-116页

作者： Hongqiang Lu Yida Xu yukun gao Wanglong Qin Qiang Sun College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

In this paper,a DG(Discontinuous Galerkin)method which has been widely employed in CFD(Computational Fluid Dynamics)is used to solve the twodimensional time-domain Maxwell’s equations for complex geometries on unstructured *** element interfaces on solid boundary are treated in both curved way and straight *** tests are performed for both benchmark problems and complex cases with varying orders on a series of grids,where the high-order convergence in accuracy can be *** the curved and the straight solid boundary implementation can give accurate RCS(Radar Cross-Section)results with sufficiently small mesh size,but the curved solid boundary implementation can significantly improve the accuracy when using relatively large mesh *** importantly,this CFD-based high-order DG method for the Maxwell’s equations is very suitable for complex geometries.

关键词： Maxwell’s equations discontinuous Galerkin method curved mesh radar crosssection.

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Experimental study on methane dissolved in surfactant-alkane system

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International Journal of Mining Science and Technology 2020年第6期30卷 865-873页

作者： Zhian Huang Mingli Chen Jingjing Wang Yinghua Zhang Linghua Zhang Hui Wang yukun gao Yupeng Zhou State Key Laboratory of High-Efficient Mining and Safety of Metal Mines University of Science and Technology-BeijingMinistry of EducationBeijing 100083China Work Safety Key Lab on Prevention and Control of Gas and Roof Disasters for Southern Coal Mines Hunan University of Science and TechnologyXiangtan 411201China State Key Laboratory Cultivation Base for Gas Geology and Gas Control Henan Polytechnic UniversityJiaozuo 454000China Beijing Key Laboratory of Operation Safety of Gas Heating and Underground PipelinesBeijing Research Center of Urban System EngineeringBeijing 100035China

A surfactant-polyalkane system is investigated using chemical reagents to dissolve methane and control coal seam gas from low-energy,high-efficiency,safety,and environmental protection *** different temperatures and pressures,a high-temperature and high-pressure reactor,gas chromatograph,and other related experimental equipment were used to perform methane dissolution experiments,and a single surfactant sodium oleate(NaOA)and n-hexane demonstrated superior *** single-factor experiments of temperature,pressure,and NaOA addition were performed and fitted via a response surface *** optimal conditions for methane solubility were as follows:temperature of 34C,pressure of 4.5 MPa,NaOA addition of 85 g/L,and time of 1 *** optimal effect of the surfactant-polyalkane system in dissolving methane was achieved with 32.31 mL/100 ***,the change in the surface structure of coal before and after washing with the system was compared using scanning electron *** results indicated that the gas after washing with the surfactant-polyalkane system dissolved,and the surface pore structure of the coal ***,the specific surface area and pore size of the coal surface increased after ***,the desorption of gas from the coal surface into the system becomes easy,thereby reducing the gas content in the coal sample.

关键词： Surfactant Polyalkane solution Methane

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Interface electronic engineering of molybdenum sulfide/MXene hybrids for highly efficient biomimetic sensors

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Nano Research 2023年第1期16卷 1158-1164页

作者： Pengfei Wu Tingting You Qingyuan Ren Hongyan Xi Qingqing Liu Fengjuan Qin Hongfei Gu Yu Wang Wensheng Yan yukun gao Wenxing Chen Penggang Yin Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191China Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Shanghai Synchrotron Radiation Facility Zhangjiang LaboratoryShanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230029China

Interface regulation plays a key role in the electrochemical performance for *** controlling the interfacial interaction,the electronic structure of active species can be adjusted effectively at micro and nano-level,which results in the optimal reaction energy ***,we propose an interface electronic engineering scheme to design a strongly coupled 1T phase molybdenum sulfide(1T-MoS2)/MXene hybrids for constructing an efficient electrocatalytic biomimetic *** local electronic and atomic structures of the 1T-MoS2/Ti3C2TX are comprehensively studied by synchrotron radiation-based X-ray photoelectron spectroscopy(XPS),as well as X-ray absorption spectroscopy(XAS)at atomic *** and theoretical calculations show that there are interfacial stresses,atomic defects and adjustable bond-length between MoS2/MXene nanosheets,which can significantly promote biomolecular adsorption and rapid electron transfer to achieve excellent electrochemical activity and reaction *** 1T-MoS2/Ti3C2TX modified electrode shows ultra high sensitivity of 1.198μA/μM for dopamine detection with low limit of 0.05μ*** anticipate that the interface electronic engineering investigation could provide a basic idea for guiding the exploration of advanced biosensors with high sensitivity and low detection limit.

关键词： MXene molybdenum sulfide interface electronic effect biomimetic sensor X-ray absorption spectroscopy

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Peroxidase-like single Fe atoms anchored on Ti_(3)C_(2)T_(x)MXene as surface enhanced Raman scattering substrate for the simultaneous discrimination of multiple antioxidants

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Nano Research 2023年第7期16卷 10053-10060页

作者： Hongyan Xi Hongfei Gu Yurui Han Tingting You Pengfei Wu Qingqing Liu Lirong Zheng Shuhu Liu Qiang Fu Wenxing Chen yukun gao Yuting Wang Penggang Yin Key Laboratory of Bio-inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191China Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Department of Chemical Physics School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026China Institute of High Energy Physics Chinese Academy of ScienceBeijing 100029China School of Future Technology University of Science and Technology of ChinaHefei 230026China

Single-atom nanozymes(SAzymes)are emerging as promising alternatives to mimic natural enzyme,which is due to high atomic utilization efficiency,well-defined geometric,and unique electronic ***,Fe single atoms supported on Ti_(3)C_(2)T_(x)(Fe-SA/Ti_(3)C_(2)T_(x))with intrinsic peroxidase activity is developed,further constructing a sensitive Raman sensor array for sensing of five ***-SA/Ti_(3)C_(2)T_(x)shows excellent peroxidase-like performance in catalyzing the oxidation of 3,3',5,5'-tetramethylbenzidine(TMB)with colorimetric reactions.X-ray adsorption fine structure(XAFS)reveals that the electron transport between the Ti_(3)C_(2)T_(x)and Fe atoms occurs along Fe-O-Ti ligands,meanwhile the density functional theory(DFT)calculations confirm the spontaneous dissociation of H_(2)O_(2)and the formation of OH ***,the peroxidase-like Fe-SA/Ti_(3)C_(2)T_(x)was used as surface enhanced Raman scattering(SERS)substrate of oxidized TMB(TMB+)and achieved satisfied signal amplification *** the blocking effects of free radical reactions,one-off identification of 5 antioxidants,including ascorbic acid(AA),uric acid(UA),glutathione(GSH),melatonin(Mel),and tea polyphenols(TPP),could be realized with this high identifiable catalytic *** principle could realize 100%distinguish accuracy combined with linear discriminant analysis(LDA)and heat map data analysis.A wide detection concentration ranges from 10^(-8)to 10^(-3)M for five antioxidants was also achieved.

关键词： single atom catalyst Ti_(3)C_(2)T_(x)MXene atomic interface site surface enhanced Raman scattering(SERS) antioxidants

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A GPU-Accelerated Discontinuous Galerkin Method for Solving Two-Dimensional Laminar Flows

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Transactions of Nanjing University of Aeronautics and Astronautics 2022年第4期39卷 450-466页

作者： gao Huanqin CHEN Hongquan ZHANG Jiale XU Shengguan gao yukun Key Laboratory of Non-steady Aerodynamics and Flow Control of MIIT College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China School of Mechanical Engineering Anhui University of TechnologyMaanshan 243002P.R.China

A graphics processing unit(GPU)-accelerated discontinuous Galerkin(DG)method is presented for solving two-dimensional laminar *** DG method is ported from central processing unit to GPU in a way of achieving GPU speedup through programming under the compute unified device architecture(CUDA)*** CUDA kernel subroutines are designed to meet with the requirement of high order computing of DG *** corresponding data structures are constructed in component-wised manners and the thread hierarchy is manipulated in cell-wised or edge-wised manners associated with related integrals involved in solving laminar Navier-Stokes equations,in which the inviscid and viscous flux terms are computed by the local lax-Friedrichs scheme and the second scheme of Bassi&Rebay,respectively.A strong stability preserving Runge-Kutta scheme is then used for time marching of numerical *** resulting GPU-accelerated DG method is first validated by the traditional Couette flow problems with different mesh sizes associated with different orders of approximation,which shows that the orders of convergence,as expected,can be *** numerical simulations of the typical flows over a circular cylinder or a NACA 0012 airfoil are then carried out,and the results are further compared with the analytical solutions or available experimental and numerical values reported in the literature,as well as with a performance analysis of the developed code in terms of GPU *** shows that the costs of computing time of the presented test cases are significantly reduced without losing accuracy,while impressive speedups up to 69.7 times are achieved by the present method in comparison to its CPU counterpart.

关键词： discontinuous Galerkin GPU compute unified device architecture(CUDA) Navier-Stokes equation laminar flows

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Diversity of depositional architecture and sandbody distribution of sublacustrine fans during forced regression: A case study of Paleogene Middle Sha 3 Member in Dongying Sag, Bohai Bay Basin, East China

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Petroleum Exploration and Development 2023年第4期50卷 894-908页

作者： WU Qianran XIAN Benzhong gao Xianzhi TIAN Rongheng ZHANG Haozhe LIU Jianping gao yukun WANG Pengyu State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China School of Petroleum Engineering Chongqing University of Science and TechnologyChongqing 401331China

Currently, the differences in gravity flow deposits within different systems tracts in continental lacustrine basins are not clear. Taking the middle submember of the third member of Paleogene Shahejie Formation(Sha 3 Member) in the Shishen 100 area of the Dongying Sag in the Bohai Bay Basin as an example, the depositional architecture of sublacustrine fans during forced regression and the impact of the fourth-order base-level changes on their growth were investigated using cores, well logs and 3D seismic data. Sublacustrine fans were mainly caused by hyperpycnal flow during the fourth-order base-level rise, while the proportion of slump-induced sublacustrine fans gradually increased during the late fourth-order base-level fall. From rising to falling of the fourth-order base-level, the extension distance of channels inside hyperpycnal-fed sublacustrine fans reduced progressively, resulting in the transformation in their morphology from a significantly channelized fan to a skirt-like fan. Furthermore, the depositional architecture of distributary channel complexes in sublacustrine fans changed from vertical aggradation to lateral migration, and the lateral size of individual channel steadily decreased. The lobe complex's architectural patterns evolved from compensational stacking of lateral migration to aggradational stacking, and the lateral size of individual lobe steadily grew. This study deepens the understanding of depositional features of gravity flow in high-frequency sequence stratigraphy and provides a geological foundation for the fine development of sublacustrine fan reservoirs.

关键词： Bohai Bay Basin Dongying Sag Paleogene Shahejie Formation sublacustrine fan hyperpycnal flow gravity flow base-level depositional architecture

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求解三维麦克斯韦方程的时域无网格算法研究

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电波科学学报 2015年第2期30卷 257-263页

作者：高煜堃陈红全南京航空航天大学航空宇航学院江苏南京210016

发展了用于求解三维麦克斯韦方程的时域无网格算法.算法基于生成的无网格点云,通过泰勒级数展开结合加权最小二乘逼近计算点云中心点上的空间导数,并构造近似黎曼解处理空间离散涉及的通量运算;空间离散后的半离散方程则采用四步RungeKu... 详细信息

发展了用于求解三维麦克斯韦方程的时域无网格算法.算法基于生成的无网格点云,通过泰勒级数展开结合加权最小二乘逼近计算点云中心点上的空间导数,并构造近似黎曼解处理空间离散涉及的通量运算;空间离散后的半离散方程则采用四步RungeKutta格式推进求解.结合求解三维麦克斯韦方程,给出了时域无网格算法的具体实施过程,并基于发展的算法,成功地模拟出金属球、立方体及进气道模型等三维散射目标的电磁散射场,获得的雷达散射截面能与理论解、矩量法或精确控制法等结果吻合.

关键词：时域无网格算法麦克斯韦方程点云加权最小二乘三维

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手机信令数据在职住空间、出行行为和交通碳排放研究中的应用进展与前景

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热带地理 2024年第5期44卷 877-890页

作者：高瑜堃赵鹏军北京大学城市与环境学院北京100871 北京大学深圳研究生院城市规划与设计学院广东深圳518055

手机信令数据具有覆盖范围广、获取成本低、时空精度较高、稳定实时追踪等优势,能够有效识别大规模人群的空间活动和出行特征,已成为应用最广泛的交通大数据类型之一。文章在手机信令数据的分类和特征基础上,总结了其在职住空间关系和... 详细信息

手机信令数据具有覆盖范围广、获取成本低、时空精度较高、稳定实时追踪等优势,能够有效识别大规模人群的空间活动和出行特征,已成为应用最广泛的交通大数据类型之一。文章在手机信令数据的分类和特征基础上,总结了其在职住空间关系和交通出行行为研究中的技术应用,随后结合上述应用成果和已有文献对其在交通碳排放研究中的应用潜力和场景进行了探讨,最后总结了手机信令数据在职住空间、出行行为和交通碳排放研究中的应用框架、应用机遇与挑战以及未来研究内容与技术创新方向。目前,手机信令数据在职住空间领域中的应用包括职住地识别、职住关系和通勤网络特征及其影响因素解析,在出行行为领域中的应用包括驻留-出行识别、出行方式和路径识别,以及人群移动普适规律解析。以上技术应用能够有效服务交通碳排放领域研究,为交通碳排放测算以及城市空间结构、居民出行行为对交通碳排放的影响研究奠定了基础。未来,相关研究应进一步关注长时序动态追踪、大范围对比分析以及人口和交通新现象研究,并注重多源数据的融合、传统方法与机器学习的结合以及数字孪生模型的构建。

关键词：手机信令数据职住空间关系交通出行行为交通碳排放

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