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Wellbore Cleaning Degree and Hydraulic Extension in Shale Oil Horizontal Wells

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Fluid Dynamics & materials Processing 2024年第3期20卷 661-670页

作者： Xin ai mian Chen College of Petroleum Engineering China University of Petroleum(Beijing)BeijingChina Daqing Oil Field Company Limited DaqingChina

The efficient development and exploitation of shale oil depends on long-distance horizontal wells. As the degreeof cleaning of the wellbore plays a key role in these processes, in this study, this problem is investigated experimentallyby focusing on the dimensionless cuttings bed height. A method is proposed to calculate the horizontalwellhydraulic extension taking into account the influence of the wellbore cleaning degree on the wellborepressure distribution and assess the effect of a variety of factors such as the bottom hole pressure, the circulatingpressure drop, the drilling pump performance and the formation properties. The analysis shows that the hydraulicextension of horizontal wells decreases with an increase in the cuttings bed height, and the higher the displacementof drilling fluid, the faster the hydraulic extension declines. The annular pressure drop of the horizontalsection increases with the increase of the cuttings bed height, resulting in a higher bottom-hole pressure. Severalarguments are provided to guide the safe drilling of shale oil horizontal wells and overcome the limits of currenttechnological approaches.

关键词： Shale oil horizontal well hydraulic extension wellbore cleaning degree pressure distribution mechanism analysis

Nanoscale Reorganization of Glutamate Receptors Underlies Synaptic Plasticity and Pathology

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Neuroscience Bulletin 2024年第6期40卷 840-844页

作者： Jia-Hui Chen ai-Hui Tang Hefei National Laboratory for Physical Sciences at the microscale CAS Key Laboratory of Brain Function and DiseaseNeurodegenerative Disorder Research Center and Biomedical Sciences and Health Laboratory of Anhui ProvinceUniversity of Science and Technology of ChinaHefei230027China Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefei230088China

Excitatory synapses serve as the primary sites for information transmission between neurons in the *** work over the past decades has identified and revealed multiple compositions and functions of the synaptic proteome in the postsynaptic density(PSD),including receptors,scaffold proteins,and signaling molecules,which work together to ensure stable and effective synaptic transmission.

关键词： Receptor scale Glutamate

Preparation of Polyurea Elastomer with Flame Retardant, Insulation and Thermal Conductivity Properties

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Journal of Wuhan University of Technology(materials Science) 2024年第3期39卷 781-789页

作者：方今 DONG Yang LU Shangkai LIU Junbang ai Lianghui 刘平 State Key Laboratory of Luminescent materials and Devices Research Institute of Materials ScienceSouth China University of TechnologyGuangzhou 510640China

By using 6,6-((sulfonylbis(4,1-phenylene)bis(azanediyl))bis(thiophen-2-ylm-ethylene))bis6H-di-benzo[c,e][1,2]oxaphosphinine 6-oxide(DOPO-N)as phosphorus-nitrogen flame retardant,the polyurea(PUA)with flame retardant properties(PUA/DOPO-N)was *** addition,organically modified montmorillonite(OmmT)and magnesium hydroxide(mH)were used as co-effectors respectively,and the flame retardant PUA(PUA/DOPO-N/OmmT and PUA/DOPO-N/mH)were also *** properties,flame retardant properties,flame retardant mechanism and mechanical properties of PUA/DOPO-N,PUA/DOPO-N/OmmT and PUA/DOPO-N/mH were investigated by thermogravimetric(TG)analysis,limiting oxygen index(LOI),UL 94,cone calorimeter test,scanning electron microscopy(SEm),and tensile *** results show that the LOI value of PUA/20%DOPO-N,PUA/18%DOPO-N/2%OmmT and PUA/15%DOPO-N/5%mH are 27.1%,27.7%,and 28.3%,respectively,and UL 94 V-0 rating is *** with PUA,the peak heat release rate(pk-HRR),total heat release(THR)and average effective heat combustion(av-EHC)of PUA/20%DOPO-N,PUA/18%DOPO-N/2%OmmT and PUA/15%DOPO-N/5%mH decrease *** results indicate that the residual chars of PUA/20%DOPO-N,PUA/18%DOPO-N/2%OmmT and PUA/15%DOPO-N/5%mH are completer and more *** complex of DOPO-N/OmmT and DOPO-N/mH have synergistic flame *** mechanical properties of PUA can be improved by the addition of DOPO-N,DOPO-N/OmmT and DOPO-N/mH,*** insulation performance test shows that the volume resistivity of PUA/20%DOPO-N is 6.25×10^(16)Ω.***,by using modified boron nitride(mBN)as heat dissipating material,the complex of PUA/mBN was prepared,and the thermal conductivity of PUA/mBN was *** thermal conductivity of PUA/8%mBN complex coating at room temperature is 0.166 W/(m·K),which is a 163%improvement over pure PUA.

关键词： polyurea organic flame retardant inorganic flame retardant synergistic flame retardancy insulation thermal conductivity

Numerical analysis of wind effects on aerodynamic characteristics of a ducted fan

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Chinese Journal of Aeronautics 2024年第5期37卷 263-280页

作者： Yiwei LUO Tianfu ai Yuhang HE Bin XU Yuping QIAN Yangjun ZHANG State Key Laboratory of Intelligent Green Vehicle and mobility School of Vehicle and MobilityTsinghua UniversityBeijing 100084China Key Laboratory of Conveyance and Equipment ministry of Education East China Jiaotong UniversityNanchang 330013China Vehicle Research Center School of Mechanical EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

Ducted fans have been extensively used in Unmanned Aerial Vehicles(UAVs)for a variety of missions because of high efficiency,high safety and low ***,as a kind of typical meteorological condition,brings significant aerodynamic interference to the ducted fan,which seriously threatens flight stability and *** this work,the numerical simulation with the Unsteady Reynolds Averaged Navier-Stokes(URANS)method and the sliding mesh technique is performed to evaluate the steady wind *** results show that the wind will lead to serious unsteady effects in the flow field,and the thrust fluctuates at the blade passing frequency of 200 *** the wind speed increases,the rotor thrust increases,the duct thrust decreases,and the total thrust changes *** instability may occur when the wind speed exceeds 8 m/*** the angle of low-speed wind increases,the rotor thrust changes little,the duct thrust increases,and the total thrust *** addition,we figure out that cases with the same crosswind ratio are similar in results,and increasing the rotating speed or fan radius is beneficial to performance improvement in *** findings are essential to the ducted fan design and UAV flight control design for stable and safe operations in wind conditions.

关键词： Unmanned Aerial Vehicle(UAV) Ducted fan Wind effect Thrust fluctuations Computational Fluid Dynamics(CFD)

Fast efficient photon deceleration in plasmas by using two laser pulses at different frequencies

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matter and Radiation at Extremes 2024年第3期9卷 11-18页

作者： Y.X.Wang X.L.Zhu S.m.Weng P.Li X.F.Li H.ai H.R.Pan Z.m.Sheng Key Laboratory for Laser Plasmas(moe) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Collaborative Innovation Center of IFSA Shanghai Jiao Tong UniversityShanghai 200240China Research Center of Laser Fusion of China Academy of Engineering Physics MianyangSichuan 621900China State key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China Tsung-dao Lee Institute Shanghai Jiao Tong UniversityShanghai 200240China

The generation of ultrashort high-power light sources in the mid-infrared(mid-IR)to terahertz(THz)range is of interest for applications in a number of fields,from fundamental research to biology and *** conventional laser technology,photon deceleration in plasma wakes provides an alternative approach to the generation of ultrashort mid-IR or THz ***,we present a photon deceleration scheme for the efficient generation of ultrashort mid-IR or THz pulses by using an intense driver laser pulse with a relatively short wavelength and a signal laser pulse with a relatively long *** signal pulse trails the driver pulse with an appropriate time delay such that it sits at the front of the second wake bubble that is driven by the driver *** to its relatively long wavelength,the signal pulse will be subjected to a large gradient of the refractive index in the plasma wake ***,the photon deceleration in the plasma wake becomes faster and more efficient for signal pulses with longer *** greatly enhances the capacity and efficiency of photon deceleration in the generation of ultrashort high-power light sources in the long-wavelength IR and THz spectral ranges.

关键词： laser ultrashort photon

A Novel Divide and Conquer Solution for Long-term Video Salient Object Detection

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machine Intelligence Research 2024年第4期21卷 684-703页

作者： Yun-Xiao Li Cheng-Li-Zhao Chen Shuai Li ai-min Hao Hong Qin State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijing 100191China College of Computer Science and Technology China University of Petroleum(East China)Qingdao 266580China Department of Computer Science Stony Brook UniversityNew York 11794USA

Recently,a new research trend in our video salient object detection(VSOD)research community has focused on enhancing the detection results via model self-fine-tuning using sparsely mined high-quality keyframes from the given *** such a learning scheme is generally effective,it has a critical limitation,i.e.,the model learned on sparse frames only possesses weak generalization *** situation could become worse on“long”videos since they tend to have intensive scene ***,in such videos,the keyframe information from a longer time span is less relevant to the previous,which could also cause learning conflict and deteriorate the model ***,the learning scheme is usually incapable of handling complex pattern *** solve this problem,we propose a divide-and-conquer framework,which can convert a complex problem domain into multiple simple ***,we devise a novel background consistency analysis(BCA)which effectively divides the mined frames into disjoint *** for each group,we assign an individual deep model on it to capture its key attribute during the fine-tuning *** the testing phase,we design a model-matching strategy,which could dynamically select the best-matched model from those fine-tuned ones to handle the given testing *** experiments show that our method can adapt severe background appearance variation coupling with object movement and obtain robust saliency detection compared with the previous scheme and the state-of-the-art methods.

关键词： Video salient object detection background consistency analysis weakly supervised learning long-term information background shift.

Interactions between myoblasts and macrophages under high glucose milieus result in inflammatory response and impaired insulin sensitivity

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World Journal of Diabetes 2024年第7期15卷 1589-1602页

作者： Wei Luo Yue Zhou Li-Ying Wang Lei ai Department of Sports and Health Sciences Nanjing Sport InstituteNanjing 210014Jiangsu ProvinceChina Department of Exercise Physiology Beijing Sport UniversityBeijing 100084China Department of Sports Physiology Research Jiangsu Research Institute of Sports ScienceNanjing 210033Jiangsu ProvinceChina

BACKGROUND Skeletal muscle handles about 80% of insulin-stimulated glucose uptake and become the major organ occurring insulin resistance(IR).many studies have confirmed the interactions between macrophages and skeletal muscle regulated the inflammation and regeneration of skeletal ***,despite of the decades of research,whether macrophages infiltration and polarization in skeletal muscle under high glucose(HG)milieus results in the development of IR is yet to be elucidated.C2C12 myoblasts are well-established and excellent model to study myogenic regulation and its responses to *** exploration of macrophages'role in myoblasts IR and the dynamics of their infiltration and polarization is *** To evaluate interactions between myoblasts and macrophages under HG,and its effects on inflammation and IR in skeletal *** We detected the polarization status of macrophages infiltrated to skeletal muscles of IR mice by hematoxylin and eosin and immunohistochemical ***,we developed an in vitro co-culture system to study the interactions between myoblasts and macrophages under HG *** effects of myoblasts on macrophages were explored through morphological observation,CCK-8 assay,Flow Cytometry,and enzyme-linked immunosorbent *** mediation of macrophages to myogenesis and insulin sensitivity were detected by morphological observation,CCK-8 assay,Immunofluorescence,and 2-NBDG *** The F4/80 and co-localization of F4/80 and CD86 increased,and the myofiber size decreased in IR group(Pmpared to mc group,F4/80+CD86+CD206-cells,tumor necrosis factor-α(TNFα),inerleukin-1β(IL-1β)and IL-6 decreased,and IL-10 increased in mcm group(P0.8).In mcm+HG group,F4/80+CD86+CD206-cells,monocyte chemoattractant protein 1,TNFα,IL-1βand IL-6 were increased,and F4/80+CD206+CD86-cells and IL-10 were decreased compared with mc+HG group and mcm group(P0.8).Compered to m group,myotube area,myotube n

关键词： macrophages phenotype myoblasts Cross-talk Glucose toxicity Chronic inflammation Insulin sensitivity

mitigating Straggler Effect in Federated Learning Based on Reconfigurable Intelligent Surface over Internet of Vehicles

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China Communications 2024年第8期21卷 62-78页

作者： Li Zejun Wu Hao Lu Yunlong Dai Yueyue ai Bo School of Electronic and Information Engineering Beijing Jiaotong UniversityBeijing 100044China Frontiers Science Center for Smart High-Speed Railway System Beijing 100044China Beijing Engineering Research Center of High-Speed Railway Broadband mobile Communications Beijing 100044China Research Center of 6G mobile Communications School of Cyber Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

To protect vehicular privacy and speed up the execution of tasks,federated learning is introduced in the Internet of Vehicles(IoV)where users execute model training locally and upload local models to the base station without massive raw data ***,heterogeneous computing and communication resources of vehicles cause straggler effect which weakens the reliability of federated *** out vehicles with limited resources confines the training *** a result,the accuracy and applicability of federated learning models will be *** mitigate the straggler effect and improve performance of federated learning,we propose a reconfigurable intelligent surface(RIS)-assisted federated learning framework to enhance the communication reliability for parameter transmission in the ***,we optimize the phase shift of RIS to achieve a more reliable communication *** addition,we define vehicular competence to measure both vehicular trustworthiness and *** on the vehicular competence,the straggler effect is mitigated where training tasks of computing stragglers are offloaded to surrounding vehicles with high *** experiment results verify that our proposed framework can improve the reliability of federated learning in terms of computing and communication in the IoV.

关键词： reliable federated learning RIS straggler effect vehicular competence

High temperature polyimide nanocomposites containing twodimensional nanofillers for improved thermal stability and capacitive energy storage performance

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Nano Research 2024年第8期17卷 7746-7755页

作者： Ding ai Yuting Han Zongliang Xie Xi Pang Yuan Chang He Li Chenglong Wu Yonghong Cheng Guanglei Wu State Key Laboratory of Electrical Insulation and Power Equipment School of Electrical EngineeringXi’an Jiaotong UniversityXi’an 710049China Institute of materials for Energy and Environment State Key Laboratory of Bio-Fibers and Eco-TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China

Future electronic devices toward high integration and miniaturization demand reliable operation of dielectric materials at high electric fields and elevated ***,the electrical deterioration caused by Joule heat generation remains a persistent challenge to ***,the solution-processed polyimide(PI)nanocomposites with unique two-dimensional(2D)alumina nanoplates are *** improvements in the breakdown strength,charge–discharge efficiency and discharged energy density at elevated temperatures have been demonstrated in the composites,owing to simultaneously suppressed conduction loss and increased thermal conductivity upon the incorporation of 2D Al2O3 nanofillers possessing excellent dielectric insulation and thermophysical *** predominance of Al2O3 nanoplates in enhancing thermal stability and high-temperature capacitive performance over nanoparticles and nanowires is validated experimentally and is further rationalized via finite element ***,the Al2O3 nanoplates filled PI nanocomposite exhibits a hightemperature capability up to 200℃and remarkable efficiency(e.g.≥95%at 200 mV/m)over a wide temperature range,which outperforms commercial dielectric polymers and rivals the state-of-the-art polyimide nanocomposites.

关键词： capacitors polymer nanocomposites high temperature energy storage thermal stability