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Analysis of mechanical strengths of extreme line casing joint considering geometric, material, and contact nonlinearities

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Petroleum Science 2024年第3期21卷 1992-2004页

作者： ji-Yun Zhang Chi Peng jian-Hong Fu Quan cao Yu Su jian-Yun Pang Zi-Qiang Yu Petroleum Engineering School Southwest Petroleum UniversityChengdu610500SichuanChina Engineering Technology Research Institute of CNPC Southwest Oil and Gas Field Company Chengdu610017SichuanChina

To address the challenges associated with difficult casing running,limited annular space,and poor cementing quality in the completion of ultra-deep wells,the extreme line casing offers an effective solution over conventional ***,due to its smaller size,the joint strength of extreme line casing is reduced,which may cause failure when running in the *** address this issue,this study focuses on the CST-ZTΦ139.7 mm×7.72 mm extreme line casing and employs the elastic-plastic mechanics to establish a comprehensive analysis of the casing joint,taking into account the influence of geometric and material nonlinearities.A finite element model is developed to analyze the forces and deformations of the extreme line casing joint under axial tension and external collapse *** model investigates the stress distribution of each thread tooth subjected to various tensile forces and external ***,the tensile strength and crushing strength of the extreme line casing joint are determined through both analytical and experimental *** findings reveal that,under axial tensile load,the bearing surface of each thread tooth experiences uneven stress,with relatively high equivalent stress at the root of each thread *** end thread teeth are valuable spots for *** is observed that the critical fracture axial load of thread decreases linearly with the increase of thread tooth *** external pressure,the circumferential stress is highest at the small end of the external thread,leading to yield *** tensile strength of the joint obtained from the finite element model exhibits a relative error of less than 7%compared to the analytical and experimental values,proving the reliability of the finite element *** tensile strength of the joint is 3091.9 k ***,in terms of anti-collapse capability,the joints demonstrate higher resistance to collapse compared to the casing body,which is consistent with the test resul

关键词： Extreme line casing Elastic-plastic mechanics Finite element analysis Tensile strength Collapse strength

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应用层组播稳定性提高技术综述

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计算机学报 2009年第3期32卷 576-590页

作者：苏金树曹继军张博锋国防科学技术大学计算机学院长沙410073

互联网上组通信应用的日益普及和传统IP组播发展面临的困境导致应用层组播逐步受到广泛关注.将组播功能从路由器迁移到主机能够有效解决许多与IP组播相关的问题,但同时也带来一些新的挑战,如应用层组播稳定性问题.文中概述了应用层组播... 详细信息

互联网上组通信应用的日益普及和传统IP组播发展面临的困境导致应用层组播逐步受到广泛关注.将组播功能从路由器迁移到主机能够有效解决许多与IP组播相关的问题,但同时也带来一些新的挑战,如应用层组播稳定性问题.文中概述了应用层组播的数据传输模型、组播树构造算法和协议性能评价标准,阐述了应用层组播稳定性问题产生的原因,提出了衡量应用层组播稳定性的标准,分析了影响应用层组播稳定性的因素,根据影响因素将应用层组播稳定性提高技术分类为降低节点离开事件发生频率的方法、缩小节点离开事件影响范围的方法以及缩短节点离开事件发生后组播树恢复时间的方法,并介绍了各种应用层组播稳定性提高技术,展望了该领域未来的研究工作.

关键词：组播应用层组播稳定性影响因素综述

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The dynamics beamline at SSRF

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Nuclear Science and Techniques 2024年第9期35卷 56-67页

作者： Zhen Liu Li-Hua Wang Yong jiang Ya-jun Tong Hua-Chun Zhu Te ji Min Chen Zheng jiang Xiang-jun Wei Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201204China ShanghaiTech University Shanghai 201210China

The dynamics beamline(D-Line),which combines synchrotron radiation infrared spectroscopy(SR-IR)and energy-disper-sive X-ray absorption spectroscopy(ED-XAS),is the first beamline in the world to realize concurrent ED-XAS and SR-IR measurements at the same sample position on a millisecond time-resolved *** combined technique is effective for investigating rapid structural changes in atoms,electrons,and molecules in complicated disorder systems,such as those used in physics,chemistry,materials science,and extreme ***,ED-XAS and SR-IR can be used independently in the two branches of the *** ED-XAS branch is the first ED-XAS beamline in China,which uses a tapered undulator light source and can achieve approximately 2.5×10^(12)photons/s·300 eV BW@7.2 keV at the sample *** exchange-able polychromator operating in the Bragg-reflection or Laue-transmission configuration is used in different energy ranges to satisfy the requirements for beam size and energy *** focused beam size is approximately 3.5μm(H)×21.5μm(V),and the X-ray energy range is 5–25 *** one-and two-dimensional position-sensitive detectors with frame rates of up to 400 kHz enables time resolutions of tens of microseconds to be *** distinctive techniques,such as the concurrent measurement of in situ ED-XAS and infrared spectroscopy,time-resolved ED-XAS,high-pressure ED-XAS,XMCD,and pump-probe ED-XAS,can be applied to achieve different scientific goals.

关键词： ED-XAS SR-IR Time-resolved D-line SSRF

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Pillar effect induced by ultrahigh phosphorous/nitrogen doping enables graphene/MXene film with excellent cycling stability for alkali metal ion storage

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Journal of Energy Chemistry 2024年第6期93卷 146-156,I0004页

作者： Meng Qin Yiwei Yao junjie Mao Chi Chen Kai Zhu Guiling Wang Dianxue cao jun Yan Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001HeilongjiangChina Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials and Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen 361021FujianChina

Graphene's large theoretical surface area and high conductivity make it an attractive anode material for potassium-ion batteries(PIBs).However,its practical application is hindered by small interlayer distance and long ion transfer ***,this paper aims to address the issue by introducing MXene through a simple and scalable method for assembling graphene and realizing ultrahigh P doping *** findings reveal that MXene and P-C bonds have a "pillar effect" on the structure of graphene,and the P-C bond plays a primary *** addition,N/P co-doping introduces abundant defects,providing more active sites for K^(+) storage and facilitating K^(+) *** expected,the developed ultrahigh phosphorous/nitrogen co-doped flexible reduced graphene oxide/MXene(NPrGM) electrode exhibits remarkable reversible discharge capacity(554 mA hg^(-1) at 0.05 A g^(-1)),impressive rate capability(178 mA h g^(-1) at 2 A g^(-1)),and robust cyclic stability(0.0005% decay per cycle after 10,000 cycles at 2 A g^(-1)).Furthermore,the assembled activated carbon‖NPrGM potassium-ion hybrid capacitor(PIHC) can deliver an impressive energy density of 131 W h kg^(-1) and stable cycling performance with 98.1% capacitance retention after5000 cycles at 1 A g^(-1).Such a new strategy will effectively promote the practical application of graphene materials in PIBs/PIHCs and open new avenues for the scalable development of flexible films based on two-dimensional materials for potential applications in energy storage,thermal interface,and electromagnetic shielding.

关键词： Graphene MXene Phosphorous doping Pillar effect Potassium-ion batteries

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Magnetic NiFe_(2)O_(4)@FeNi_(3)core-shell nanospheres derived from FeNi-LDH precursor anchoring on rGO nanosheets for enhanced electromagnetic wave absorption

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Journal of Materials Science & Technology 2024年第4期171卷 101-114页

作者： Kunyao cao Yuan Fang Shuai Wang Yue Zhang jiayue Wen jun Chen Rui Zhao Weidong Xue School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 610054China

Graphene has been extensively utilized in the domain of electromagnetic wave(EMW)absorption ma-terials because of its excellent electrical ***,the inferior impedance matching per-formance and the single loss mechanism vastly restrict the ***,it’s an effective strat-egy to solve these issues by introducing magnetic ***,layer double hydroxide(LDH)is an appropriate template to obtain magnetic component *** that ferromagnetic met-als such as Fe,Co,Ni,and their corresponding metal oxides are usually treated as magnetic compo-nents which are promising candidates for EMW absorption ***,in this work,a FeNi-layered double hydroxide-reduced graphene oxide(FeNi-LDH-rGO)aerogel was synthesized through a series of processes such as electrostatic self-assembly,hydrothermal,freeze-drying,and *** magnetic NiFe_(2)O_(4)@FeNi_(3)core-shell nanospheres were obtained from FeNi-LDH precursor,anchoring on rGO nanosheets after the annealing ***,the effects of different mass ratios of LDH to GO as well as different annealing temperatures of LDH-rGO aerogel on the EMW absorption prop-erty and impedance matching performance were *** a consequence,the fabricated ultralight 600LDH-rGO 2:1 aerogel shows a broad effective absorption bandwidth(EAB)of 7.04 GHz at a thickness of 2.3 mm with a low filling content of only 6 wt%and a low density of 4.4 mg/cm^(3).In conclusion,the synthetic LDH-rGO aerogels offer an effective strategy for preparing EMW absorption materials that own three-dimensional porous network structure and unique magnetic NiFe_(2)O_(4)@FeNi_(3)core-shell struc-ture nanospheres.

关键词： Electrostatic self-assembly Electromagnetic wave absorption LDH-rGO aerogel Layered double hydroxide Reduced graphene oxide NiFe_(2)O_(4)@FeNi_(3)core-shell structure

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Preparation and properties of high-energy-density aluminum/boroncontaining gelled fuels

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Chinese Journal of Chemical Engineering 2024年第1期65卷 230-242页

作者： Yi Chen Kang Xue Yang Liu Lun Pan Xiangwen Zhang ji-jun Zou Key Laboratory for Green Chemical Technology of the Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Collaborative Innovative Center of Chemical Science and Engineering(Tianjin) Tianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China Zhejiang Institute of Tianjin University Ningbo 315201China

Energetic nanofluid fuel has caught the attention of the field of aerospace liquid propellant for its high energy density(HED), but it suffers from the inevitable solid-liquid phase separation problem. To resolve this problem, herein we synthesized the high-Al-/B-containing(up to 30%(mass)) HED gelled fuels, with low-molecular-mass organic gellant Z, which show high net heat of combustion(NHOC), density, storage stability, and thixotropic properties. The characterizations indicate that the application of energetic particles to the gelled fuels obviously destroys their fibrous network structures but can provide the new particle-gellant gelation microstructures, resulting in the comparable stability between 1.0%(mass) Z/JP-10 + 30%(mass) Al or B and pure JP-10 gelled fuel. Moreover, the gelled fuels with high-content Al or B exhibit high shear-thinning property, recovery capability, and mechanical strength, which are favorable for their storage and utilization. Importantly, the prepared 1.0%(mass) Z/JP-10 + 30%(mass) B(or 1.0%(mass) Z/JP-10 + 30%(mass) Al) shows the density and NHOC 1.27 times(1.30) and 1.43 times(1.21)higher than pure JP-10, respectively. This work provides a facile and valid approach to the manufacturing of HED gelled fuels with high content of energetic particles for gel propellants.

关键词： Gelled fuels Energetic aluminum/boron Low-molecular-mass organic gellant Fuel property

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Eosinophils promote CD8+ T cell memory generation to potentiate anti-bacterial immunity

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Signal Transduction and Targeted Therapy 2024年第3期9卷 1230-1243页

作者： jun Zhou jiaqi Liu Bingjing Wang Nan Li Juan Liu Yanmei Han Xuetao cao Institute of Immunology Zhejiang University School of MedicineHangzhou 310058China National Key Laboratory of Immunity and Inflammation Institute of ImmunologyNaval Medical UniversityShanghai 200433China Department of Immunology Center for ImmunotherapyInstitute of Basic Medical SciencesPeking Union Medical CollegeChinese Academy of Medical SciencesBeijing 100005China Institute of Immunology College of Life SciencesNankai UniversityTianjin 300071China

Memory CD8+T cell generation is crucial for pathogen elimination and effective vaccination against *** cellular and molecular circuitry that underlies the generation of memory CD8+T cells remains *** can modulate inflammatory allergic responses and interact with lymphocytes to regulate their functions in immune *** we report that eosinophils are required for the generation of memory CD8+T cells by inhibiting CD8+T cell ***-deficient mice display significantly impaired memory CD8+T cell response and weakened resistance against Listeria monocytogenes(L.m.)***,eosinophils secrete interleukin-4(IL-4)to inhibit JNK/Caspase-3 dependent apoptosis of CD8+T cells upon *** in ***,active eosinophils are recruited into the spleen and secrete more IL-4 to suppress CD8+T cell apoptosis during early stage of *** in *** transfer of wild-type(WT)eosinophils but not IL-4-deficient eosinophils into eosinophil-deficient mice could rescue the impaired CD8+T cell memory ***,our findings suggest that eosinophil-derived IL-4 promotes the generation of CD8+T cell memory and enhances immune defense against *** study reveals a new adjuvant role of eosinophils in memory T cell generation and provides clues for enhancing the vaccine potency via targeting eosinophils and related cytokines.

关键词： impaired immunity spleen

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Melatonin and dopamine alleviate waterlogging stress in apples by recruiting beneficial endophytes to enhance physiological resilience

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Journal of Integrative Agriculture 2024年第7期23卷 2270-2291页

作者： Yang cao Peihua Du Yuwei Shang jiahao ji Leiqing Tan Xue Zhang jizhong Xu Bowen Liang College of Horticulture Hebei Agricultural UniversityBaoding 071001China

Melatonin and dopamine can potentially prevent waterlogging stress in *** current study investigated the mechanism by which melatonin and dopamine alleviate apple waterlogging *** study demonstrated that melatonin and dopamine alleviated waterlogging by removing reactive oxygen species(ROS),and that the nitric oxide(NO)content and nitrate reductase(NR)activity were significantly *** and dopamine were also found to recruit different candidate beneficial endophytes(melatonin:Novosphingobium,Propionivibrio,and Cellvibrio;dopamine:Hydrogenophaga,Simplicispira,Methyloversatilis,Candidatus_Kaiserbacteria,and Humicola),and these endophytes were significantly and positively correlated with plant *** analyses showed that melatonin and dopamine significantly affected the endophytic bacterial and fungal communities under waterlogging *** metabolomic results showed that melatonin and dopamine led to waterlogging resistance by upregulating the abundance of beneficial substances such as amino acids,flavonoids,coumarins,and organic *** addition,melatonin and dopamine regulated the physicochemical properties of the soil,which altered the endophyte community and affected plant *** co-occurrence network demonstrated close and complex relationships among endophytes,metabolites,soil,and the *** results demonstrate that melatonin and dopamine alleviate waterlogging stress in apples by recruiting beneficial endophytes to enhance physiological *** study provides new insights into how melatonin and dopamine alleviate stress and a theoretical basis for synergistic beneficial microbial resistance to waterlogging stress.

关键词： dopamine endophytes Malus hupehensis melatonin metabolomics waterlogging

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Integrated assessment of yield,nitrogen use efficiency and ecosystem economic benefits of use of controlled-release and common urea in ratoon rice production

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Journal of Integrative Agriculture 2024年第9期23卷 3186-3199页

作者： Zijuan Ding Ren Hu Yuxian cao jintao Li Dakang Xiao jun Hou Xuexia Wang College of Agriculture Yangtze University/MARA Key Laboratory of Sustainable Crop Production in the Middle Reaches of the Yangtze River(Co-construction by Ministry and Province)Jingzhou 434025China College of Life Science Yangtze UniversityJingzhou 434025China Institute of Plant Nutrition Resources and EnvironmentBeijing Agricultural Forestry Academy SciencesBeijing 100097China

Controlled-release urea(CRU)is commonly used to improve the crop yield and nitrogen use efficiency(NUE).However,few studies have investigated the effects of CRU in the ratoon rice *** rice is the practice of obtaining a second harvest from tillers originating from the stubble of the previously harvested main *** this study,a 2-year field experiment using a randomized complete block design was conducted to determine the effects of CRU on the yield,NUE,and economic benefits of ratoon rice,including the main crop,to provide a theoretical basis for fertilization of ratoon *** experiment included four treatments:(i)no N fertilizer(CK);(ii)traditional practice with 5 applications of urea applied at different crop growth stages by surface broadcasting(FFP);(iii)one-time basal application of CRU(BF1);and(iv)one-time basal application of CRU combined with common urea(BF2).The BF1 and BF2 treatments significantly increased the main crop yield by 17.47 and 15.99%in 2019,and by 17.91 and 16.44%in 2020,respectively,compared with FFP *** BF2 treatment achieved similar yield of the ratoon crop to the FFP treatment,whereas the BF1 treatment significantly increased the yield of the ratoon crop by 14.81%in 2019 and 12.21%in 2020 compared with the FFP *** BF1 and BF2 treatments significantly improved the 2-year apparent N recovery efficiency,agronomic NUE,and partial factor productivity of applied N by 11.47-16.66,27.31-44.49,and 9.23-15.60%,respectively,compared with FFP *** BF1 and BF2 treatments reduced the chalky rice rate and chalkiness of main and ratoon crops relative to the FFP ***,emergy analysis showed that the production efficiency of the BF treatments was higher than that of the FFP *** BF treatments reduced labor input due to reduced fertilization times and improved the economic benefits of ratoon *** with the FFP treatment,the BF1 and BF2 treatments increased the net income by 14.21-16

关键词： ratoon rice controlled-release urea yield nitrogen use efficiency economic benefit

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代理型应用层组播体系结构研究

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计算机科学 2009年第5期36卷 45-50页

作者：曹继军苏金树国防科技大学计算机学院长沙410073

组通信技术是未来互联网应用的关键支撑技术。目前,应用层组播是组通信技术研究中的热点,而代理型应用层组播体系结构已成为组播体系结构研究的重要方向之一。首先概述和比较了IP组播、主机型应用层组播和代理型应用层组播3种组播体系结... 详细信息

组通信技术是未来互联网应用的关键支撑技术。目前,应用层组播是组通信技术研究中的热点,而代理型应用层组播体系结构已成为组播体系结构研究的重要方向之一。首先概述和比较了IP组播、主机型应用层组播和代理型应用层组播3种组播体系结构,接着重点研究和分析了代理型应用层组播体系结构的研究现状。以此为基础,进一步总结了代理型应用层组播体系结构设计中需要考虑的基本问题,并针对现有体系结构的不足,探讨了设计新的代理型应用层组播体系结构中值得关注的问题。最后对未来工作进行了展望。

关键词： IP组播应用层组播主机型代理型组播体系结构

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