检索结果-南通市图书馆

Evaluating the stability and volumetric flowback rate of proppant packs in hydraulic fractures using the lattice Boltzmann-discrete element coupling method

引用

Journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2052-2063页

作者： Duo wang Sanbai li Rui wang Binhui li Zhejun Pan National Key Laboratory of Continental Shale Oil Northeast Petroleum UniversityDaqing163318China Institute of Unconventional Oil&Gas Northeast Petroleum UniversityDaqing163318China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen518055China National Center for Applied Mathematics Shenzhen(NCAMS) Southern University of Science and TechnologyShenzhen518055China National Key Laboratory of Continental Shale Oil Daqing Oilfield of CNPCDaqing163002China Daqing Oilfield Exploration and Development Research Institute DaqingHeilongjiang163712China

The stability and mobility of proppant packs in hydraulic fractures during hydrocarbon production are numerically investigated by the lattice Boltzmann-discrete element coupling method(LB-DEM).This study starts with a preliminary proppant settling test,from which a solid volume fraction of 0.575 is calibrated for the proppant pack in the *** the established workflow to investigate proppant flowback,a displacement is applied to the fracture surfaces to compact the generated proppant pack as well as further mimicking proppant embedment under closure *** a pressure gradient is applied to drive the fluid-particle flow,a critical aperture-to-diameter ratio of 4 is observed,above which the proppant pack would *** results also show that the volumetric proppant flowback rate increases quadratically with the fracture aperture,while a linear variation between the particle flux and the pressure gradient is exhibited for a fixed fracture *** research outcome contributes towards an improved understanding of proppant flowback in hydraulic fractures,which also supports an optimised proppant size selection for hydraulic fracturing operations.

关键词： Numerical simulation Hydraulic fracturing Proppant flowback Closure stress Particulate flow

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A single Eu^(2+)-activated high-color-rendering oxychloride white-light phosphor for white-light-emitting diodes

引用

light(Science & Applications) 2016年第1期5卷 677-685页

作者： Peng-Peng Dai Cong li Xin-Tong Zhang Jun Xu Xi Chen xiu-li wang Yan Jia Xiaojun wang Yi-Chun liu Center for Advanced Optoelectronic Functional Materials Research and Key Laboratory for UV-Emitting Materials and Technology of Ministry of EducationNortheast Normal University5268 Renmin StreetChangchun 130024China Department of Chemistry University of ZurichThe X-ray Crystallography Facility and The Linden Research GroupWinterthurerstrasse190 CH-8057 ZurichSwitzerland School of life Sciences Northeast Normal University5268 Renmin StreetChangchun 130024China Department of Physics Georgia Southern UniversityStatesboroGA 30460USA

Single-phased,high-color-rendering index(CRI)white-light phosphors are emerging as potential phosphor-converted white-light-emitting diodes(WLEDs)and as an alternative to blends of tricolor ***,it is a challenge to create a high CRI white light from a single-doped ***,we present a high CRI(Ra 591)white-light phosphor,Sr_(5)(PO_(4))_(3-x)(BO_(3))_(x)Cl:Eu^(2+),composed of Sr5(PO4)3Cl as the beginning member and Sr_(5)(BO_(3))_(3)Cl as the end *** work utilized the solid-solution method,and tunable Eu^(2+) emission was ***-tunable Eu^(2+) emissions in response to structural variation were observed in Sr_(5)(PO_(4))_(3-x)(BO_(3))_(x)Cl solid *** was further confirmed using X-ray Rietveld refinement,electron paramagnetic resonance spectroscopy,and in the photoluminescence *** color-tunable emissions included the white light that originated from the combination of the blue emission of Sr_(5)(PO_(4))_(3)Cl:Eu^(2+) and an induced Eu^(2+) yellow emission at approximately 550 nm in the solid ***,the white-light phosphors showed a greater R9590.2 under excitation at 365 *** result has rarely been reported in the literature and is greater than that of(R9514.3)commercial Y_(3)A_(l5)O_(12):Ce^(3+)-based *** findings demonstrate the great potential of Sr_(5)(PO_(4))_(3-x)(BO_(3))_(x)Cl:0.04Eu^(2+) as a white-light phosphor for near-UV phosphor-converted *** results also provide a shortcut for developing a high CRI white-light phosphor from a single Eu^(2+)-doped compound.

关键词： high-color-rendering single Eu^(2+)-activated solid solution white-emitting phosphor

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A combined liouville integrable hierarchy associated with a fourth-order matrix spectral problem

引用

Communications in Theoretical Physics 2024年第7期76卷 1-8页

作者： Wen-xiu Ma Department of Mathematics Zhejiang Normal UniversityJinhua 321004China Department of Mathematics King Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Mathematics and Statistics University of South Florida TampaFL 33620-5700United States of America Material Science Innovation and Modelling Department of Mathematical SciencesNorth-West UniversityMafikeng CampusMmabatho 2735South Africa

This paper aims to propose a fourth-order matrix spectral problem involving four potentials and generate an associated liouville integrable hierarchy via the zero curvature formulation.A bi-Hamiltonian formulation is furnished by applying the trace identity and a recursion operator is explicitly worked out,which exhibits the liouville integrability of each model in the resulting *** specific examples,consisting of novel generalized combined nonlinear Schrodinger equations and modified Korteweg-de Vries equations,are given.

关键词： integrable hierarchy Hamiltonian structure zero curvature equation Lax pair matrix spectral problem

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Four-channel catalytic micro-reactor based on alumina hollow fiber membrane for efficient catalytic oxidation of CO

引用

Chinese Journal of Chemical Engineering 2024年第7期71卷 140-147页

作者： Baichuan Xu Bin wang Tao li Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 211100China

The traditional automotive catalytic converter using commercial ceramic honeycomb carriers has many problems such as high back pressure,low engine efficiency,and high usage of precious *** study proposes a four-channel catalytic micro-reactor based on alumina hollow fiber membrane,which uses phase inversion method for structural molding and *** to the advantages of its carrier,it can achieve lower ignition temperature under low noble metal *** Pd/CeO_(2) at a loading rate of 2.3%(mass),the result showed that the reaction ignition temperature is even less than 160℃,which is more than 90℃ lower than the data of commercial ceramic substrates under similar catalyst loading and airspeed *** technology in turn significantly reduces the energy consumption of the *** stability tests were conducted under constant conditions for 1000 h,which proved that this catalytic converter has high catalytic efficiency and stability,providing prospects for the design of innovative catalytic converters in the future.

关键词： Catalytic converter Precious metal catalyst Phase inversion method Hollow fiber membrane CO oxidation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Accurately tracking hypersonic gliding vehicles via an LEO mega-constellation in relay tracking mode

引用

Journal of Systems Engineering and Electronics 2024年第1期35卷 211-221页

作者： li Zhao wang Yidi ZHENG Wei College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

In order to effectively defend against the threats of the hypersonic gliding vehicles(HGVs),HGVs should be tracked as early as possible,which is beyond the capability of the ground-based *** benefited by the developing megaconstellations in low-Earth orbit,this paper proposes a relay tracking mode to track HGVs to overcome the above *** whole tracking mission is composed of several tracking intervals with the same *** each tracking interval,several appropriate satellites are dispatched to track the *** that are planned to take part in the tracking mission are selected by a new derived observability *** tracking performances of the proposed tracking mode and the other two traditional tracking modes,including the stare and track-rate modes,are compared by *** results show that the relay tracking mode can track the whole trajectory of a HGV,while the stare mode can only provide a very short tracking ***,the relay tracking mode achieve higher tracking accuracy with fewer attitude controls than the track-rate mode.

关键词： target tracking mega-constellation hypersonic gliding vehicle(HGV) sensor selection observability analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Constructing long-cycling crystalline C_(3)N_(4)-based carbonaceous anodes for sodium-ion battery via N configuration control

引用

Carbon Energy 2024年第1期6卷 159-171页

作者： Ying wang Hongguan li Shuanlong Di Boyin Zhai Ping Niu Antonios Kelarakis Shulan wang li li School of Metallurgy Northeastern UniversityShenyangLiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyangLiaoningChina Department of Chemistry College of ScienceNortheastern UniversityShenyangLiaoningChina School of Natural Sciences UCLan Research Centre for Smart MaterialsUniversity of Central LancashirePrestonUK Foshan Graduate School of Innovation Northeastern UniversityFoshanGuangdongChina

Carbon nitrides with two-dimensional layered structures and high theoretical capacities are attractive as anode materials for sodium-ion batteries while their low crystallinity and insufficient structural stability strongly restrict their practical *** carbon nitrides with conductive carbon may relieve these ***,little is known about the influence of nitrogen(N)configurations on the interactions between carbon and C_(3)N_(4),which is fundamentally critical for guiding the precise design of advanced C_(3)N_(4)-related ***,highly crystalline C_(3)N_(4)(poly(triazine imide),PTI)based all-carbon composites were developed by molten salt *** importantly,the vital role of pyrrolic-N for enhancing charge transfer and boosting Na+storage of C_(3)N_(4)-based composites,which was confirmed by both theoretical and experimental evidence,was spot-highlighted for the first *** elaborately controlling the salt composition,the composite with high pyrrolic-N and minimized graphitic-N content was *** from the formation of highly crystalline PTI and electrochemically favorable pyrrolic-N configurations,the composite delivered an unusual reverse growth and record-level cycling stability even after 5000 cycles along with high reversible capacity and outstanding full-cell capacity *** work broadens the energy storage applications of C_(3)N_(4) and provides new prospects for the design of advanced all-carbon electrodes.

关键词： anode highly crystalline C_(3)N_(4) N configuration sodium-ion batteries ultra-long cyclic stability

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Crack propagation and damage evolution of metallic cylindrical shells under internal explosive loading

引用

DEFENCE TECHNOLOGY 2024年第9期39卷 133-146页

作者： Luo, Yusong li, Weibing li, Junbao li, Wenbin wang, Xiaoming Nanjing Univ Sci & Technol ZNDY Ministerial Key Lab Nanjing 210094 Peoples R China

This paper investigates the three-dimensional crack propagation and damage evolution process of metallic column shells under internal explosive loading. The calibration of four typical failure parameters for 40CrMnSiB steel was conducted through experiments and subsequently applied to simulations. The numerical simulation results employing the four failure criteria were compared with the differences and similarities observed in freeze-recovery tests and ultra-high-speed tests. This analysis addressed the critical issue of determining failure criteria for the fracture of a metal shell under internal explosive loads. Building upon this foundation, the damage parameter Dc, linked to the cumulative crack density, was defined based on the evolution characteristics of a substantial number of cracks. The relationship between the damage parameter and crack velocity over time was established, and the influence of the internal central pressure on the damage parameter and crack velocity was investigated. Variations in the fracture modes were found under different failure criteria, with the principal strain failure criterion proving to be the most effective for simulating 3D crack propagation in a pure shear fracture mode. Through statistical analysis of the shell penetration fracture radius data, it was determined that the fracture radius remained essentially constant during the crack evolution process and could be considered a constant. The propagation velocity of axial cracks ranged between 5300 m/s and 12600 m/s, surpassing the Rayleigh wave velocity of the shell material and decreasing linearly with time. The increase in shell damage exhibited an initial rapid phase, followed by deceleration, demonstrating accelerated damage during the propagation stage of the blast wave and decelerated damage after the arrival of the rarefaction wave. This study provides an effective approach for investigating crack propagation and damage evolution. The derived crack propagation and damag

关键词： Internal explosive loading Failure criterion Crack propagation Damage evolution Freeze-recovery test INTERMEDIATE PHASE SHEAR-BAND STEEL FRAGMENTATION DEFORMATION MECHANISM

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Vision-based survey method for extraordinary loads on buildings

引用

Frontiers of Structural and Civil Engineering 2024年第6期18卷 815-831页

作者： Yang li Jun CHEN Pengcheng wang College of Civil Engineering Tongji UniversityShanghai 200092China China United Engineering Co.Ltd. Hangzhou 310052China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China Shanghai Key Laboratory of Engineering Structure Safety Shanghai Research Institute of Building Sciences Co.Ltd.Shanghai 200032China

The statistical modeling of extraordinary loads on buildings has been stagnant for decades due to the laborious and error-prone nature of existing survey methods,such as questionnaires and verbal *** study proposes a new vision-based survey method for collecting extraordinary load data by automatically analyzing surveillance *** this purpose,a crowd head tracking framework is developed that integrates crowd head detection and reidentification models based on convolutional neural networks to obtain head trajectories of the crowd in the survey *** crowd head trajectories are then analyzed to extract crowd quantity and velocities,which are the essential factors for extraordinary *** survey areas with frequent crowd movements during temporary events,the equivalent dynamic load factor can be further estimated using crowd velocity to consider dynamic effects.A crowd quantity investigation experiment and a crowd walking experiment are conducted to validate the proposed survey *** experimental results prove that the proposed survey method is effective and accurate in collecting load data and reasonable in considering dynamic effects during extraordinary *** proposed survey method is easy to deploy and has the potential to collect substantial and reliable extraordinary load data for determining design load on buildings.

关键词： load survey extraordinary load live load object detection multiple-object tracking

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Understanding Human and Machine Interaction from Decision Perspective: An Empirical Study Based on the Game of Go

引用

Journal of Systems Science & Complexity 2024年第2期37卷 647-667页

作者： ZHAO Ping li Xuerong wang Shouyang Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100190China

The authors aim to interpret human and AI interactions from the decision *** authors decompose the interaction analysis into the following main components in the context of interactions:Individual behavior patterns,interaction relationships,and comprehensive *** authors interpret intertemporal decisions from a physical perspective and employ cross-discipline concepts and methodologies to extract the behavior characteristics of players in the empirical case *** the individual behavior patterns,the authors find that human players prefer short-term periods to AI in *** interaction relationship analysis reveals a dynamic relationship between possible short-term co-movement and nearly counter-movement in the long *** authors apply principal component analysis to descriptive indicators and discover a regular decision *** main behavior pattern of players in the game of Go is switching between careful and daring *** differences in the decision hierarchies imply a discrepancy of patience between humans and AI.

关键词： Coherence analysis decision hierarchy machine behaviour multitaper spectral analysis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Experimental study on combustion characteristics of supersonic combustor based on alternating-wedge strut

引用

Chinese Journal of Aeronautics 2024年第5期37卷 214-227页

作者： Jie li Wenyan SONG Yuhang wang School of Power Energy Northwestern Polytechnical UniversityXi’an 710129China

Acetone Planar Lase-Induced Fluorescence(PliF)and OH-PliF were employed to capture the fuel distribution and OH distribution downstream for the supersonic combustor based on the alternating-wedge *** combustion establishment process and combustion mode in the combustor under different fuel injection methods and different equivalence ratios were *** with the kerosene-PliF and OH-PliF results in the cavity combustor,a comparative analysis was conducted to understand the combustion characteristics and combustion modes between the alternating-wedge strut-based combustor and the cavity-based *** results show that the combustor is in weak combustion mode in the case of low equivalence ratio,and the combustor is in intensive combustion mode in the case of high equivalence *** lower limit of the equivalence ratio of the combustor to maintain the intensive combustion mode varies based on different fuel injection *** OH distribution under reacting condition has a strong correlation with the fuel distribution under non-reacting *** OH fluorescence signal near the injector is weaker when the fuel distribution is more *** injector position located at the base of the strut rear has better mixing performance,enabling the combustor to be in intensive combustion mode at a lower equivalence *** combustion reaction in the alternating-wedge strut-based combustor is not necessarily dominated by mass transfer due to the mixing enhancement and premixed zone downstream of strut,while the combustion reaction process in the cavity-based combustor is mainly influenced by mass transfer.

关键词： Supersonic combustor Alternating-wedge strut Cavity PliF Fuel injection Fuel distribution Combustion characteristics Combustion mode

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：