检索结果-南通市图书馆

Experimental study on proppant-carrying migration and settlement of slickwater in narrow plate fractures based on PIV / PTV

引用

PETROLEUM 2024年第3期10卷 494-510页

作者： Zhang, Tao Tang, Tang Guo, Jianchun zhou, hangyu Liu, Yuxuan Zhang, Yifan Zeng, Xianjin Southwest Petr Univ State Key Lab Oil & Gas Reservoir Geol & Exploitat Chengdu 610500 Peoples R China CNOOC Ltd Hainan Branch Haikou 570300 Hainan Peoples R China

Hydraulic fracturing is the primary method used for oilfield stimulation, and the migration and settlement pattern of proppant plays a crucial role in the formation of high conductivity propping fractures in the reservoir. This study summarizes two growth modes of sand dune: the 'overall longitudinal growth' mode and the 'push growth along fracture length direction' mode. To investigate these modes, a twophase velocity test is conducted using PIV, and the exposure difference is utilized to separate the tracer and track the single-phase velocity. By analyzing the slickwater flow field and proppant velocity field, the micro-motion mechanism behind the two dune growth modes is quantitatively examined. The results indicate that mode 1 growth of the sand dune occurs when a pump with a large mesh number, high polymer viscosity, and large displacement is used. On the other hand, mode 2 growth is observed when a pump with a small mesh number, low polymer viscosity, and small displacement is employed. It is important to note that there is no clear boundary for the migration and sedimentation mode of proppant, as they can transition into each other under certain conditions. These modes only exist during specific stages of sand dune growth. In the case of the 'backflow' pattern, the settlement of proppant is primarily influenced by the vortex structure of slickwater. Conversely, in the 'direct' pattern, the proppant is propelled forward by the drag of the fluid and settles due to its own gravity. Once the proppant placement reaches equilibrium, the direction of proppant velocity follows a normal distribution within 0 degrees. This approach establishes a connection between the overall placement of the sand dune and the microscopic movement of the proppant and slickwater. Optimizing construction parameters during fracturing construction can enhance the effectiveness of distal proppant placement in fractures. (c) 2023 Southwest Petroleum University. Publishing services by Elsevie

关键词： Slickwater fracturing Proppant transport Multiphase flow PIV/PTV HYDRAULIC FRACTURES PARTICLE IMAGE TRANSPORT FLOW GAS OPTIMIZATION SIMULATION TURBULENCE PLACEMENT DYNAMICS

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

天然油松叶-枝-根氮磷含量随降水和温度的变化规律

引用

北京林业大学学报 2024年第1期46卷 44-54页

作者：周航宇付琪瑶梁婉婷宋沼鹏侯继华北京林业大学生态与自然保护学院北京100083

【目的】对油松叶、枝、根的氮、磷含量随水热变化的响应规律进行研究,有助于加深对我国暖温带地区森林植物应对气候变化策略的认识。【方法】本文基于生态化学计量学理论,在我国天然油松林主要分布区选择7个代表性样点,对优势种油松叶... 详细信息

【目的】对油松叶、枝、根的氮、磷含量随水热变化的响应规律进行研究,有助于加深对我国暖温带地区森林植物应对气候变化策略的认识。【方法】本文基于生态化学计量学理论,在我国天然油松林主要分布区选择7个代表性样点,对优势种油松叶、枝、根的氮、磷含量进行定量分析。【结果】(1)油松叶、枝、根器官间氮、磷含量存在显著差异,叶的氮、磷含量均高于枝和根的氮、磷含量,其中当年生叶、当年生枝的氮、磷含量高于多年生叶、多年生枝的氮、磷含量。吸收根氮、磷含量高于次生根氮、磷含量。当年生叶、当年生枝的氮磷比低于多年生叶、多年生枝的氮磷比,次生根氮磷比高于吸收根氮磷比。(2)油松叶、枝、根的氮、磷含量的变异程度存在差异,整体变异系数范围为12.3%~44.4%,其中吸收根磷含量的变异系数最大,多年生叶氮含量的变异系数最小。(3)油松不同器官的氮磷化学计量特征随环境变化的响应存在差异,油松多年生叶氮含量、多年生及当年生枝氮、磷含量随降水量的增加呈显著下降的趋势。多年生及当年生叶磷含量、枝磷含量均随温度的升高呈显著上升的趋势。多年生及当年生叶氮磷比、枝氮磷比随温度的升高呈显著下降的趋势。次生根磷含量随温度的升高呈显著上升的趋势,次生根氮磷比随温度升高呈显著下降的趋势。【结论】降水、温度对我国天然油松林优势物种油松叶、枝、根的氮磷化学计量特征有显著影响,不同器官应对这两个环境因子的响应趋势及适应机制不同。

关键词：油松叶-枝-根氮、磷化学计量气候因子土壤因子

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

深层页岩压裂多级裂缝内支撑剂运移与分布规律

引用

天然气工业 2024年第7期44卷 1-11页

作者：郭建春唐堂张涛周航宇刘彧轩李明峰杨若愚油气藏地质与开发全国重点实验室·西南石油大学中国石油西南油气田公司页岩气研究院中国石油西南油气田公司勘探事业部

深层页岩天然裂缝与层理缝发育,经体积改造后易形成“主缝+支缝+次微缝”的多级裂缝结构,但受高垂向应力和高水平应力差条件的影响,深层页岩压裂裂缝开度极窄且主次缝开度差异较大。为了明确多级裂缝内支撑剂运移机制与分布规律,搭建了... 详细信息

深层页岩天然裂缝与层理缝发育,经体积改造后易形成“主缝+支缝+次微缝”的多级裂缝结构,但受高垂向应力和高水平应力差条件的影响,深层页岩压裂裂缝开度极窄且主次缝开度差异较大。为了明确多级裂缝内支撑剂运移机制与分布规律,搭建了大型可视化支撑剂输送实验系统,研究了泵注排量、液体黏度、支撑剂粒径、支撑剂浓度、裂缝特征参数对支撑剂运移与分布的影响规律,最后基于水电相似原理计算了裂缝整体导流能力并开展了评价分析。研究结果表明:①缝内支撑剂存在多种堆积模式,其形成由流体对支撑剂的携带能力决定;②支撑剂分流效率受多种因素影响,增大排量与减小支撑剂粒径均可提高分流效率;③多级裂缝内,增大排量与压裂液黏度均在一定程度上改善了支撑剂非均匀分布,但裂缝导流能力表现为先增大后减小;④综合支撑剂分流结果与多级裂缝内支撑剂分布规律,推荐坚持“大排量+低黏度”泵注思想,以保证大粒径支撑剂占比,适当混合小粒径支撑剂,构建“近井区高导流+远井区有支撑”的高导流裂缝体。结论认为,基于含多级裂缝的大型可视化支撑剂输送实验系统,全面系统研究了不同条件下多级裂缝内支撑剂运移与堆积的模式,研究成果可为深层页岩压裂泵注工艺参数设计与优化提供理论支撑。

关键词：深层页岩体积压裂多级裂缝水平裂缝支撑剂运移缝内分布室内实验系统

来源：

维普期刊数据库博看期刊

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

阻燃聚合物电解质高稳定锂负极界面研究进展

引用

中国安全生产科学技术 2024年第8期20卷 13-18页

作者：周航宇高尚高嘉良曹轩康荣学中国安全生产科学研究院北京100012 应急管理部国家安全科学与工程研究院北京100012

为高效发挥阻燃聚合物电解质所具备的轻质、柔性、固-固界面相容性好等优势,推动电化学能源存储体系向安全可靠的全固态转型,基于锂离子(Li^(+))配位团簇结构复杂等特点,分析分子间通过竞争作用调控阻燃聚合物电解质衍生的固体电解质界... 详细信息

为高效发挥阻燃聚合物电解质所具备的轻质、柔性、固-固界面相容性好等优势,推动电化学能源存储体系向安全可靠的全固态转型,基于锂离子(Li^(+))配位团簇结构复杂等特点,分析分子间通过竞争作用调控阻燃聚合物电解质衍生的固体电解质界面膜(SEI)所面临的挑战,综述国内外阻燃聚合物电解质高稳定性界面构筑、锂离子配位结构设计、离子输运机制、界面热稳定性等方面的研究进展,预测聚合物电解质内部分子间作用主导调控的Li^(+)配位结构在提高锂金属-电解质稳定性领域的应用前景,展望未来全固态锂金属电池中阻燃聚合物电解质的研究发展方向。研究结果表明:调控Li^(+)配位团簇结构是提高锂金属负极/阻燃聚合物电解质界面稳定性的关键。研究结果可为全固态锂金属电池实际应用提供界面设计参考。

关键词：阻燃聚合物电解质固体电解质界面锂负极配位结构全固态锂金属电池

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

Observation of Magnetic Dipole Forbidden Transitions in LHD and Its Application to Burning Plasma Diagnostics

引用

Plasma Science and Technology 2010年第3期12卷 341-347页

作者： Shigeru MORITA Motoshi GOTO Ryuji KATAI Chunfeng DONG Hiroyuki SAKAUE hangyu zhou National Institute for Fusion Science Institute of Laser Engineering Osaka University Graduate University for Advanced Studies

Magnetic dipole forbidden （M1） transition was studied in large helical device （LHD） and F-, Si- and Ti-like M1 transitions are successfully observed for highly ionized Ar, Kr, Mo and Xe ions. The wavelengths measured in visible range for the heavy elements, which are carefully determined with extremely small uncertainties of 0.02 - 0.05 A as a standard wavelength of usual electric dipole （El） plasma emissions, are compared with theoretical predictions. The result shows a good agreement with recent Hatree-Fock calculation including semi-empirical adjustment. The M1 intensity for the F-like ions is examined by analyzing the intensity ratio of M1 to El. Density dependence of the ratio is experimentally verified by comparing with collisional- radiative model calculation on level population. The M1/E1 line ratio for the F-like ions is applied to the α （He^2＋） particle diagnostics in ITER, in which a steady-state operation of burning plasmas based on D-T fusion reaction is expected with α particle heating. Unfortunately, the present estimation suggests a negative result for the α particle measurement because the ratio is largely enhanced by the collisional excitation with bulk ions due to high ion temperature of ITER of 10 keV as assumed and the resultant effect of the collisional excitation with α particles becomes less. Meanwhile, the M1 transition, in particular, Ti-like WLIII （W^52＋） transition （3627 A） emitted in visible range, is very useful for diagnostics of the impurity behavior and the core plasma parameters in ITER.

关键词： magnetic dipole transition, α particle ITER

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

Regulating the growth of lithium dendrite by coating an ultra-thin layer of gold on separator for improving the fast-charging ability of graphite anode

引用

Journal of Energy Chemistry 2022年第4期31卷 467-473页

作者： Shuaishuai Yan Xiaoxia Chen Pan zhou Peican Wang hangyu zhou Weili Zhang Yingchun Xia Kai Liu The State Key Laboratory of Chemical Engineering Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

With the ever-growing application of lithium-ion batteries(LIBs), their fast-charging technology has attracted great interests of scientists. However, growth of lithium dendrites during fast charge of the bat teries with high energy density may pose great threats to the operation and cause serious safety issues Herein, we prepared a functional separator with an ultra-thin(20 nm) layer of Au nanoparticles deposited by evaporation coating method which could regulate growth direction and morphology of the lithium dendrites, owing to nearly zero overpotential of lithium meal nucleation on lithiated Au. Once the Li den drites are about to form on the graphite anode during fast charging(or lithiation), they plate predomi nantly on the Au deposited separator rather than on the graphite. Such selective deposition does no compromise the electrochemical performance of batteries under normal cycling. More importantly, i enables the better cycling stability of batteries at fast charge condition. The Li/Graphite cells with Au nanoparticles coated separator could cycle stably with a high areal capacity retention of 90.5% over 95 cycles at the current density of 0.72 m A cm^(-2). The functional separator provides an effective strategy to adjust lithium plating position at fast charge to ensure high safety of batteries without a compromise on the energy density of LIBs.

关键词： Fast-charging Functional separator Lithium-ion batteries Dendrites Safety

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

海空跨域航行器研究现状及关键力学问题

引用

力学与实践 2024年第4期46卷 683-688页

作者：周航宇魏照宇祝发勋胡卫强上海交通大学海洋学院上海200240 海军工程大学兵器工程学院武汉430034

海空跨域航行器作为一种新兴运载器,具备空中飞行、水下航行及多次主动出入水能力,能够在潜艇作战、通信中继、海洋遥感等军事及民事领域发挥独特作用,受到了各个领域研究学者的广泛关注。本文梳理了海空跨域航行器样机类型及技术路线,... 详细信息

海空跨域航行器作为一种新兴运载器,具备空中飞行、水下航行及多次主动出入水能力,能够在潜艇作战、通信中继、海洋遥感等军事及民事领域发挥独特作用,受到了各个领域研究学者的广泛关注。本文梳理了海空跨域航行器样机类型及技术路线,认为目前跨域航行器的研究重8混合翼型,重点问题应该在出入水和水下航行过程中。本文提出了一些针对性解决方案,涵盖了跨域航行器的近海面稳定性研究、快速出入水轨迹及载荷研究、水下航行力学研究等,为未来的发展和实际应用提供了有力指导。

关键词：海空跨域航行器分类出入水水下航行力学

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

Recovery and Genetic Characterization of a West Nile Virus Isolate from China

引用

Virologica Sinica 2021年第1期36卷 113-121页

作者： Yan Guo Hongjiang Wang Songtao Xu hangyu zhou Chao zhou Shihong Fu Mengli Cheng Fan Li Yongqiang Deng Xiaofeng Li Huanyu Wang Cheng-Feng Qin Department of Virology State Key Laboratory of Pathogen and BiosecurityBeijing Institute of Microbiology and EpidemiologyAcademy of Military Medical Sciences(AMMS)Beijing 100071China PLA Strategic Support Force Characteristic Medical Center Beijing 100071China Department of Arbovirus NHC Key Laboratory of BiosafetyNational Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China State Key Laboratory for Infectious Disease Prevention and Control Chinese Center for Disease Control and PreventionBeijing 102206China Suzhou Institute of System Medicine Chinese Academy of Medical Sciences and Peking Union Medical CollegeSuzhou 215000China Department of Immunology Key Laboratory of Immune Microenvironment and DiseaseNanjing Medical UniversityNanjing 211166China

West Nile virus(WNV)is an important neurotropic flavivirus that is widely distributed *** strain XJ11129 was first isolated in Xinjiang,China,and its genetic and biological characteristics remain largely *** this study,phylogenetic and sequence analyses revealed that XJ11129 belongs to lineage 1 a and shares high genetic identity with the highly pathogenic strain ***,the full-length genomic c DNA of XJ11129 was amplified and assembled using a modified Gibson assembly(GA)*** virus(named r XJ11129)was successfully rescued in days following this *** with other wild-type WNV isolates,r XJ11129 exhibited virulence indistinguishable from that of the NY99 strain in *** summary,the genomic and virulence phenotypes of r XJ11129 were characterized in vivo and in vitro,and these data will improve the understanding of the spread and pathogenesis of this reemerging virus.

关键词： WNV isolates from China Phylogenetic analysis GA method Biological characteristic

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

Large spin Hall effect and tunneling magnetoresistance in iridium-based magnetic tunnel junctions

引用

Science China(Physics,Mechanics & Astronomy) 2020年第1期63卷 86-92页

作者： JiaQi zhou Hang Yu zhou Arnaud Boumel WeiSheng Zhaop Fert Beijing Institute BDBCSchool of MicroelectronicsBeihang UniversityBeijing 100191China Centre de Nanosciences et de Nanotechnologies CNRSUniversite Paris-SudUniversite Paris-SaclayPalaiseau 91120France

Magnetic tunnel junctions(MTJs)switched by spin-orbit torque(SOT)have attracted substantial interest owing to their advantages of ultrahigh speed and prolonged *** field-free magnetization switching and high tunneling magnetoresistance(TMR)are critical for the practical application of SOT magnetic random access memory(MRAM).In this work,we propose an MTJ structure based on an iridium(Ir)bottom *** metal is a desirable candidate for field-free SOT switching owing to its strong intrinsic spin Hall conductivity(SHC),which can be enhanced via ***,we study TMR in Ir-based MTJs with symmetric and asymmetric ***-based MTJs exhibit large TMR,which can be further enhanced by heavy metal symmetry owing to the resonant tunneling *** comprehensive investigations illustrate that Ir-based MTJs are promising candidates for realizing SOT switching and high TMR.

关键词： magnetic tunnel junction spin Hall effect tunneling magnetoresistance

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

Optimal Configuration of Fault Location Measurement Points in DC Distribution Networks Based on Improved Particle Swarm Optimization Algorithm

引用

Energy Engineering 2024年第6期121卷 1535-1555页

作者： Huanan Yu hangyu Li He Wang Shiqiang Li Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology Ministry of EducationNortheast Electric Power UniversityJilin132012China

The escalating deployment of distributed power sources and random loads in DC distribution networks hasamplified the potential consequences of faults if left uncontrolled. To expedite the process of achieving an optimalconfiguration of measurement points, this paper presents an optimal configuration scheme for fault locationmeasurement points in DC distribution networks based on an improved particle swarm optimization ***, a measurement point distribution optimization model is formulated, leveraging compressive *** model aims to achieve the minimum number of measurement points while attaining the best compressivesensing reconstruction effect. It incorporates constraints from the compressive sensing algorithm and networkwide viewability. Subsequently, the traditional particle swarm algorithm is enhanced by utilizing the Haltonsequence for population initialization, generating uniformly distributed individuals. This enhancement reducesindividual search blindness and overlap probability, thereby promoting population diversity. Furthermore, anadaptive t-distribution perturbation strategy is introduced during the particle update process to enhance the globalsearch capability and search speed. The established model for the optimal configuration of measurement points issolved, and the results demonstrate the efficacy and practicality of the proposed method. The optimal configurationreduces the number of measurement points, enhances localization accuracy, and improves the convergence speedof the algorithm. These findings validate the effectiveness and utility of the proposed approach.

关键词： Optimal allocation improved particle swarm algorithm fault location compressed sensing DC distribution network

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

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：