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Load distribution in inner anchor segment of prestressed cable with time

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Load distribution in inner anchor segment of prestressed cab...

Experimental study of corner separation and unsteady characteristics in linear compressor cascades with and without sweeping jet actuator

Harmonising Rock Engineering and the Environment—12th IsRM International Congress on Rock Mechanics

作者： F.Jing w.s.li C.H.Chen & Y.K.liu Key Laboratory of Geotechnical Mechanics and Engineering of Ministry of water Resources Yangtze River scientific Research Institute wuhan China

＜正＞1 INTRODUCTION Because prestressed cables can fully take advantage of the self-supporting ability of rock mass and the self-strength of steel,adjust the self-strength of rock mass,reduce the material consumption and the construction cost estimate,and can also guarantee the safe and stability of engineering and construction, it has been widely applied in almost geotechnicals（Cheng et al.,1994）.But because of the high cost and difficulty of in-site experiment for the prestressed cables,the design and

关键词： rock mass rock support bolts and anchors case studies monitoring

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Propulsion and Power Research 2024年第3期13卷 360-374页

作者： s.w.Chen w.H.li C.Xu Q.H.Meng school of Energy science and Engineering Harbin Institute of TechnologyHarbinHeilongjiang 150001China AVIC shenyang Aircraft Design and Research Institute Shenyang 110035China

sweeping jet actuator(sJA)has been widely applied for activeflow control in *** this paper,the sJA character in compressor cascade and its performance for separation control in innerflows are ***-averaged and transientflowfield measurement,together with visualization methods are *** is found that endwall effects are important for both sJA behaviors and sJA performance for separation control in compressor *** is a maximum of 12.7%total pressure loss reduction with sJA placed near the separation position,close to the endwall and under *** characteristic frequencies in theflowfield contribute to the capture of influence regions of vortices and excitation *** concentrated shedding vortices and sJA jets impact region helped to judge that sJA energizes low momentumfluids in a large region and matches the high loss core *** be concrete,theflow separation control mechanism of sJA lies on the interruption of the blade suction surface boundary layer development and the restriction of the lifting of the boundary layer from end-wall towards blade suction surface.

关键词： Compressor cascade Activeflow control sweeping jet actuator Corner separation Oilflow visualization

Effect of Eu3+,Bi3+,and li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： s.w.wi Y.s.Lee Department of Physics and Integrative Institute of Basic sciences Soongsil University

we investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and li+.Our results indicate that li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of li + Photoluminescence sensitizer Rare earths

Tribological behavior of lubricant-impregnated porous polyimide

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Friction 2024年第4期12卷 711-725页

作者： Jinbang li Ningning ZHOU Janet s.s.wONG school of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211China Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms Beijing Institute of Control EngineeringBeijing 100029China Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK

Porous materials impregnated with lubricants can be used in conditions where limited lubricant is *** this work,three porous polyimides(PPI)with different densities were ***(PAO)impregnated PPI(iPPI)discs were rubbed against steel and sapphire *** operando observations of the iPPI-sapphire contacts show that oil is released under an applied load,forming a meniscus around *** at the outlet is created at high sliding *** amount of released oil increases with increasing PPI *** moduli,E*,estimated based on the actual contact size show that trapped oil in iPPIs contributes to load *** higher speeds,tribological rehydration of the contact occurs in low density iPPI,with that E*rises with *** high density PPIs,high speeds give a constantly high E*which is limited by the viscoelastic properties of the PPI network and possibly the rate of oil *** of iPPI-steel contacts is governed by the mechanical properties of the PPI,the flow of the lubricant,and the roughness of the PPI *** low-and medium-density(highly porous,high roughness)PPIs,large amount of oil is released,and lubrication is mainly via lubricant restricted in the contact in the pores and possibly tribological *** high density(low porosity)PPI,with lower roughness,hydrodynamic lubrication is achieved which gives the lowest *** results show that polymeric porous materials for effective lubrication require the optimization of its surface roughness,stiffness,oil flow,and oil retentions.

关键词： polyimide porous material friction mechanism polymer limited lubrication

Vampyroteuthis pseudoinfernalis ***.:the second extant widespread deep sea squid species of Vampyromorpha(Cephalopoda:Coleoidea)

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Zoological systematics 2024年第3期49卷 246-257页

作者： Dajun Qiu Bilin liu Yupei Guo wijesooriya A.s.w.Lakmini Yehui Tan Gang li Zhixin Ke Kaizhi li liangmin Huang CAs Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China University of Chinese Academy of sciences Beijing 100049China College of Marine sciences Shanghai Ocean UniversityShanghai 200090China

The vampire squid,Vampyroteuthis infernalis Chun,1903,is currently the only extant species in the family Vampyroteuthidae Chun,***,specimens from the Gulf of Guinea,Africa,and California suggested the possibility of additional ***,we report the second species of Vampyroteuthis,collected from the south China sea,China,which differs from *** by its tail shape,lower beak,photophores position,and the phylogenetic analysis of mitochondrial COI and nuclear large subunit ribosomal DNA(LsU)sequences:*** present by the lacking of the tail,photophores located approximately one-third of the points between the fins and end,and the lower beak with a broad,short wing;*** Qiu,liu&Huang,*** by an acuate tail,a pair of photophores located at the midpoints between the fins and tail,and a lower beak with a broad,elongate wing.

关键词： Nuclear gene mitochondrial COI phylogeny morphology south China sea

Editorial for the special Issue on Emerging Technology and Advanced Application of Nondestructive Detection for Power Equipment

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Chinese Journal of Electrical Engineering 2024年第1期10卷 1-2页

作者： li J. Mei H. li s. Tianjin University China Tsinghua shenzhen International Graduate school China Lanzhou Jiaotong University China

The rapid development of clean and renewable energy technologies represented by wind and solar energy,as well as the continuous growth of load demand,have put forward higher requirements for the safe operation of the power *** performance of power equipment based on traditional dielectric materials is often limited by various defects generated during molding,transportation,assembly,and operation,which cannot meet the reliability requirements of power systems in the new *** detection is an essential technical method in industrial development,which can detect and evaluate the defect and damage status of in-service equipment,key components,and materials without damaging the object.

关键词： service Application operation

superplasticity of fine-grained Mg-10li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.T.Jeong s.w.Lee w.J.Kim Department of Materials science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy superplasticity severe plastic deformation Grain size Grain growth

Accuracy comparison and improvement for state of health estimation of lithium-ion battery based on random partial recharges and feature engineering

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Journal of Energy Chemistry 2024年第5期92卷 591-604页

作者： Xingjun li Dan Yu søren Byg Vilsen Daniel Ioan stroe Department of Energy Aalborg UniversityAalborg 9220Denmark Department of Mathematical sciences Aalborg UniversityAalborg 9220Denmark walker Department of Mechanical Engineering The University of Texas at AustinAustinTX 78712USA

state of health(sOH)estimation of e-mobilities operated in real and dynamic conditions is essential and *** of existing estimations are based on a fixed constant current charging and discharging aging profiles,which overlooked the fact that the charging and discharging profiles are random and not complete in real *** work investigates the influence of feature engineering on the accuracy of different machine learning(ML)-based sOH estimations acting on different recharging sub-profiles where a realistic battery mission profile is *** features were extracted from the battery partial recharging profiles,considering different factors such as starting voltage values,charge amount,and charging sliding ***,features were selected based on a feature selection pipeline consisting of filtering and supervised ML-based subset *** linear regression(MLR),Gaussian process regression(GPR),and support vector regression(sVR)were applied to estimate sOH,and root mean square error(RMsE)was used to evaluate and compare the estimation *** results showed that the feature selection pipeline can improve sOH estimation accuracy by 55.05%,2.57%,and 2.82%for MLR,GPR and sVR *** was demonstrated that the estimation based on partial charging profiles with lower starting voltage,large charge,and large sliding window size is more likely to achieve higher *** work hopes to give some insights into the supervised ML-based feature engineering acting on random partial recharges on sOH estimation performance and tries to fill the gap of effective sOH estimation between theoretical study and real dynamic application.

关键词： Feature engineering Dynamic forklift aging profile state of health comparison Machine learning lithium-ion batteries

Probing the Bardeen-Kiselev black hole with the cosmological constant caused by Einstein equations coupled with nonlinear electrodynamics using quasinormal modes and greybody bounds

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Communications in Theoretical Physics 2024年第6期76卷 102-119页

作者： s R wu B Q wang Z w Long College of Physics Guizhou UniversityGuiyang 550025China College Pharmacy Guizhou University of Traditional Chinese MedicineGuiyang 550025China

In this work,we investigate a static and spherically symmetric Bardeen-Kiselev black hole(BH)with the cosmological constant,which is a solution of the Einstein-non-linear Maxwell field *** compute the quasinormal frequencies for the Bardeen-Kiselev BH with the cosmological constant due to electromagnetic and gravitational *** varying the BH parameters,we discuss the behavior of both real and imaginary parts of the BH quasinormal frequencies and compare these frequencies with the Reissner-Nordström-de sitter BH surrounded by quintessence(RN-dsQ).Interestingly,it is shown that the responses of the Bardeen-Kiselev BH with the cosmological constant and the RN-dsQ under electromagnetic perturbations are different when the charge parameter q,the state parameter w and the normalization factor c are varied;however,for the gravitational perturbations,the responses of the Bardeen-Kiselev BH with the cosmological constant and the RN-dsQ are different only when the charge parameter q is ***,compared with the gravitational perturbations,the electromagnetic perturbations can be used to understand nonlinear and linear electromagnetic fields in curved spacetime *** interesting observation is that,due to the presence of Kiselev quintessence,the electromagnetic perturbations around the Bardeen-Kiselev BH with the cosmological constant damps faster and oscillates slowly;for the gravitational perturbations,the quasinormal mode decays slowly and oscillates *** also study the reflection and transmission coefficients along with the absorption cross section in the Bardeen-Kiselev BH with the cosmological constant;it is shown that the transmission coefficients will increase due to the presence of Kiselev quintessence.

关键词： quasinormal modes greybody factors Bardeen-Kiselev black hole with cosmological constant