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Synthesis,Characterization and Electromagnetic Studies on Nanocrystalline Co_(0.5)Zn_(0.5)Fe_2O_4 Synthesized by Polyacrylamide Gel

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Journal of materials Science & Technology 2008年第3期24卷 628-632页

作者： Ruiting ma yanwen TIAN Haitao ZHAO Gang ZHANG Hui ZHAO School of materials Science and Engineering Shenyang Ligong University Shenyang 110168 China School of materials and Metallurgy Northeastern University Shenyang 110004 China

Nanocrystalline Co0.5Zn0.5Fe2O4 ferrite was synthesized by polyacrylamide gel method. The electromagnetic and microwave absorption properties of the ferrite were investigated. The results indicated that calcining temperature of the ferrite had a significant influence on the effective properties of the ferrite. When the calcining temperature was 500, 600 and 700℃, the average size of particles was 10, 30 and 80 nm, respectively. The dielectric loss （ε″） and magnetic loss （μ″） of the ferrite was around 0.65 and 0.29 at 8.2 GHz, respectively. Microwave absorption properties of the ferrites were simultaneously influenced due to the strong correlation between reflection loss and electromagnetic parameters of the ferrite.

关键词： Polyacrylamide gel Nanocrystalline Co0.5Zn0.5Fe2O4 Electromagnetic properties

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Pseudoconformal equation of state in compact-star matter from topology change and hidden symmetries of QCD

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Science China(Physics,Mechanics & Astronomy) 2019年第11期62卷 87-92页

作者： yong-Liang ma Hyun k.u Lee Won-Gi Paeng mannque Rho Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China Department of Physics Hanyang UniversitySeoul 133-791Korea Rare Isotope Science Project Institute for Basic ScienceDaejeon 305-811Korea Institut de Physique Theorique CEA Saclay91191 Gif-sur-Yvette cedexFrance

We construct a new effective field theory approach to the equation of state(EoS), dubbed pseudo-confomal model 'PCM', for nuclear and compact star matter entirely in terms of effective hadron degrees of freedom. The possible transition at n ^(2-4)n0(where n0 is the normal nuclear matter density) from hadron degrees of freedom to strongly-coupled quark.degrees of freedom,giving rise to a soft-to-hard changeover in the EoS that can accommodate the massive stars observed, is effectuated by the topology change at n1/2>~ 2n0 from sk.rmions to half-sk.rmions without involving local order-parameter fields. The mechanism exploits possible emergence of hidden scale and local symmetries of QCD at high density, leading to a precocious 'pseudo-conformal'sound velocity vs2= 1/3(in unit of c = 1) for n>~ 3n0. The resulting prediction signals a drastic departure from standard nuclear many-body theory in the density regime involved in the massive stars. We suggest that the tidal deformability implemented in gravitational waves coming from coalescing neutron stars in LIGO/Virgo-type observations could pin down the location of the topology change density n1/2.

关键词： equation of state compact star tidal deformability conformal sound velocity

Three-stage Algorithm of Estimation and Fault diagnose for Closed-loop Gas Turbine Engine Systems with Unk.own Time Delay

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Three-stage Algorithm of Estimation and Fault diagnose for C...

Additive-state-decomposition-based station-k.eping control for autonomous aerial refueling

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作者： Jia Ren Hongjun ma Guanghong yang Institute of Control Theory and Navigation Technology College of Information Science and Engineering Northeastern University

ISBN: (纸本)9781467355339

This paper proposes a three-stage estimation algorithm for identification and fault diagnose of closed-loop linear systems of gas turbine engines with unk.own time delay, which can be used for estimating parameters of systems and faults. By means of calculating the ratio of data determinant, the orders of time delay and the system are simultaneously estimated in the first stage. Then a two-stage least square identification method is applied to estimating the parameters and fault of an auxiliary CARma model with time delay has been calculated. The proposed algorithm has lower computational cost and is effective for gas turbine engine systems with unk.own time delay. Finally, a numerical example of biaxial gas turbine engine system is given to shown the effectiveness of the proposed method.

关键词： Parameter estimation Fault diagnose Unk.own time delay RELS algorithm

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Science China(Information Sciences) 2021年第11期64卷 240-242页

作者： Jinrui REN Quan QUAN Haibiao ma k.i-yuan CAI School of Automation Science and Electrical Engineering Beihang University

Dear editor,Aerial refueling(AR) is an effective method of increasing the endurance and range of aircraft by refueling them in flight [1, 2]. Station-k.eping control is the basis of autonomous aerial refueling(AAR). The station-k.eping control for AAR is a difficult task.for two main reasons. First,the receiver is disturbed by the atmospheric turbulence and the wak. vortex of the tank.r. Secondly, owing to the fuel injection in the refueling process, the mass and the center of mass of the receiver will change.

关键词： Aerial refueling station k.eping two-degree-of-freedom additive state decomposition varying mass

miR-152在结直肠癌组织中的表达及其与预后的关系

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中华肿瘤杂志 2016年第10期38卷 763-766页

作者：汪毅袁伟马肖马洁国家癌症中心中国医学科学院北京协和医学院肿瘤医院VIP病房 100021 国家癌症中心中国医学科学院北京协和医学院肿瘤医院分子肿瘤学国家重点实验室 100021

目的探讨结直肠癌及癌旁组织中miR-152的表达水平及其与结直肠癌术后患者预后的关系。方法采用实时荧光定量PCR法检测202例结直肠癌及癌旁组织中miR-152的表达水平，采用Cox比例风险模型分析miR-152的表达水平与结直肠癌患者预后的关系... 详细信息

目的探讨结直肠癌及癌旁组织中miR-152的表达水平及其与结直肠癌术后患者预后的关系。方法采用实时荧光定量PCR法检测202例结直肠癌及癌旁组织中miR-152的表达水平，采用Cox比例风险模型分析miR-152的表达水平与结直肠癌患者预后的关系。结果miR-152在结直肠癌及癌旁组织巾的相对表达水平分别为2．109±0．217和15．860±6．647，差异有统计学意义（P〈0．001）．miR-152在有、无淋巴结转移的结直肠癌组织中的相对表达水平分别为2．582±0．344和1．640±0．258．差异有统计学意义（P=0．001）。miR-152在Ⅰ～Ⅱ期、Ⅲ期和Ⅳ期结直肠癌组织中的相对表达水平分别为1．640±0．258、2．187±0．361和4．403±0．877，差异有统计学意义（P〈0．05）。单因素Cox回归分析显示，分化程度、淋巴结转移情况、TNM分期和miR-152的表达水平与结直肠癌术后患者的预后均有关（均P〈0．05）。多因素Cox回归分析显示，分化程度和TNM分期为影响结直肠癌患者预后的独立因素（均P〈0．001）。miR-152高表达与结直肠癌患者的不良预后有关（P〈0．05）。结论miR-152在结直肠癌组织中的表达水平低于相应的癌旁组织，miR-152表达水平与结直肠癌患者的淋巴结转移和TNM分期有关。miR-152有可能作为提示结直肠癌患者预后的潜在标志物。

关键词：微RNAs 结直肠肿瘤肿瘤分期肿瘤转移预后

Surface composites fabricated by vacuum infiltration casting technique

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Journal of University of Science and Technology Beijing 2005年第5期12卷 455-459页

作者： Guirong yang yuan Hao Wenming Song Jinjun Lii ying ma State k.y Laboratory for New Nonferrous Metal materials School of Materials Science and Engineering Lanzhou University of Technology Lanzhou730050 China Laboratory of Solid Lubrication Lanzhou Institute of Chinese Academy of Sciences Lanzhou 730000 China

Alumina （Al2O3） particles reinforced copper matrix surface composites were fabricated on the bronze substrate using the vacuum infiltration casting technique. Three cases were obtained in the vacuum infiltration casting technique： no infiltration, partial infiltration and full infiltration （the thick.ess of preforms do not exceed 3.5mm）. The reason of no infiltration is that the vacuum degree is not enough so that the force acting on the liquid metal is lower than the resistance due to the surface tension. Partial infiltration is because of somewhat lower vacuum degree and pouring temperature. Full desired infiltration is on account of suitable infiltration casting conditions, such as vacuum degree, pouring temperature, grain size and preheating temperature of the preform. The most important factor of affecting formation of surface composites is the vacuum degree, then pouring temperature and particle size. The infiltration mechanism was discussed on the bases of different processing conditions. The surface composite up to 3.5 mm in thick.ess with uniformly distributed Al2O3 particles could be fabricated via the vacuum infiltration casting technique.

关键词： alumina vacuum infiltration casting surface composite preform

Thermodynamic analysis and preparation of β-SiC/ZrO_2 composites

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International Journal of Minerals,Metallurgy and materials 2009年第5期16卷 581-585页

作者： Bei-yue ma Jing-k.n yu Qiang Zhu yong Sun School of materials and Metallurgy Northeastern University Shenyang 110004 China

A predominance area diagram for the Zr-Si-C-O system at 1773 k.was plotted according to correlative thermodynamic data. β-SiC/ZrO2 composites were prepared based on the phase diagram by carbothermal reduction of zircon （ZrSiO4） in argon atmosphere. Zircon and carbon black.were mixed according to the C/ZrSiO4 mass ratio of 0.2, and with 0, 1wt% and 2wt% extra addition of La2O3. Phase evolution of the mixture was investigated at 1723-1803 k.by X-ray powder diffraction, and the microstructure of the product prepared at 1803 k.for 4 h was examined by scanning electronic microscope. The results show that the decomposition of ZrSiO4 and the formation of β-SIC can be promoted by increasing the heating temperature and adding La2O3. The β-SiC/ZrO2 composites can be prepared at 1803 k.for 4 h in a mixture of zircon, carbon black.and La2O3, and the contents of β-SIC and m-ZrO2 in the product sample with 2wt% La2O3 reach the highest values of 10.8wt% and 89.2wt%, respectively. The crystal size of the products is about 200 nm.

关键词： composites silicon carbide zirconium dioxide carbothermal reduction thermodynamic analysis

A quantum‐lik. approach for text generation from k.owledge graphs

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CAAI Transactions on Intelligence Technology 2023年第4期8卷 1455-1463页

作者： Jia Zhu Xiaodong ma Zhihao Lin Pasquale De Meo k.y Laboratory of Intelligent Education Technology and Application of Zhejiang Province Zhejiang Normal UniversityJinhuaChina School of Computer Science South China Normal UniversityGuangzhouChina DICAM Department University of MessinaMessinaItaly

Recent text generation methods frequently learn node representations from graph‐based data via global or local aggregation,such as k.owledge *** all nodes are connected directly,node global representation encoding enables direct communication between two distant nodes while disregarding graph *** local representation encoding,which captures the graph structure,considers the connections between nearby nodes but misses out onlong‐range relations.A quantum‐lik. approach to learning bettercontextualised node embeddings is proposed using a fusion model that combines both encoding *** methods significantly improve on two graph‐to‐text datasets compared to state‐of‐the‐art models in various experiments.

关键词： data mining k.owledge‐based vision machine learning natural language processing text analysis

Effects of Pressure during Preparation on the Grain Orientation of Ruddlesden-Popper Structured BaLa_2Ti_3O_(10) Ceramic

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Journal of materials Science & Technology 2014年第5期30卷 455-458页

作者： Xizhong Wang Lei Guo Hongbo Guo Guohui ma Shengk.i Gong School of materials Science and Engineering Beihang University Beijing k.y Laboratory for Advanced Functional material and Thin Film Technology Beihang University

As potential thermal barrier coating （TBC） materials, Ruddlesden-Popper structured BaLn2Ti3010 （Ln = rare earth） compounds possess excellent phase stability and desirable thermo-physical properties as well as interesting anisotropic structure. In this paper, the effects of pressure during BaLa2Ti3010 （BLT） bulk.preparation on the grain orientation were investigated. BLT grains exhibited lamellar structure, but the grain orientation depended strongly on the existence of pressure during bulk.preparation. When pressure was applied, BLT grains preferentially grew along pressing direction, leading to formation of the texture parallel to pressing direction, but BLT grain orientation became relatively random when pressure was absent. However, in the small scale area, BLT grains grew preferentially along c-axis with independence on pressure during preparation. Pressure affected BLT grain orientation at the rapid growth stage according to the grain growth model of BLT.

关键词： Thermal barrier coating (TBC) Ceramics Pressure Grain growth