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Effect of yttrium and manganese addition on catalytic soot combustion activity and anti-high-temperature stability of CeO_(2) catalyst

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Journal of Rare Earths 2024年第2期42卷 334-344,I0004页

作者： Yi zhu xingyu Liu Wei Shi Jia Li Changbing Ye Ruimei Fang Huifeng zhu Shanhu Chen Li Lan College of Chemistry Biology and Environment Yuxi Normal UniversityYuxi 653100China Institute of Biology and Environmental Engineering Yuxi Normal UniversityYuxi 653100China College of Environment and Resources Chongqing Technology and Business UniversityChongqing 400067China College of Chemistry and Chemical Engineering Jiangxi Science and Technology Normal UniversityNanchang 330013China College of Materials and Mechatronics Jiangxi Science and Technology Normal UniversityNanchang 330013China

In order to analyze the influence of the addition of yttrium and manganese on the soot combustion performance and high temperature stability of CeO_(2) catalyst,a series of Y/Mn-modified CeO_(2) catalysts were prepared.The effects of structural properties,textural properties,oxygen vacancies,Ce^(3+),surface adsorbed oxygen species,reduction properties and desorption properties of oxygen species on the activity were analyzed by various characterization methods.The results of the activity test show that the addition of manganese is beneficial to enhancement of the activity,while the addition of yttrium increases the amount of reactive oxygen species,but decreases the activity.After aging at 700℃,the activity of the CeMn catalyst decreases most sharply,while the catalytic activity of the CeY catalyst can be maintained to a certain extent.Interestingly,the addition of yttrium and manganese at the same time can stabilize the activity.The fundamental reason is that yttrium and manganese move to the surface of the solid solution after aging,which increases the reduction performance of the catalyst,thus contributing to the increase of activity.Although the activity of CeYMn catalyst decreases after aging at 800℃,it is still higher than that of other catalysts aged at 700℃.

关键词： CeO_(2)catalyst Soot catalytic combustion Diesel pollution control Rare earths High temperature stability Low temperature reduction performance

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A Symmetric-Actuating Linear Piezoceramic Ultrasonic Motor Capable of Producing a Scissoring Effect

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Research 2024年第1期2023卷 571-581页

作者： Zhanmiao Li xingyu Yi Rongqi zhu Zhonghui Yu Xiaoting Yuan MohammadJavad PourhosseiniAsl Shuxiang Dong School of Materials Science and Engineering Peking UniversityBeijing 100871China College of Mechatronics and Control Engineering and Institute for Advanced StudyShenzhen UniversityShenzhen 518051China

Conventionally,to produce a linear motion,one motor’s stator is employed to drive one runner moving forward or backward.So far,there is almost no report of one electromechanical motor or piezoelectric ultrasonic motor that can directly generate two symmetrical linear motions,while this function is desired for precise scissoring and grasping in the minimally invasive surgery field.Herein,we report a brandnew symmetric-actuating linear piezoceramic ultrasonic motor capable of generating symmetrical linear motions of two outputs directly without additional mechanical transmission mechanisms.The key component of the motor is an(2×3)arrayed piezoceramic bar stator operating in the coupled resonant mode of the first longitudinal(L_(1))and third bending(B_(3))modes,leading to symmetric elliptical vibration trajectories at its two ends.A pair of microsurgical scissors is used as the end-effector,demonstrating a very promising future for high-precision microsurgical operations.

关键词： field symmetric backward

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Free-standingβ-Ta_(2)O_(5)/SWCNTs composite film for high-rate Li-ion storage

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Science China(Technological Sciences) 2024年第2期67卷 616-626页

作者： WU ZhiMin LIU JiaJia HE xingyu BIAN Jing zhu XianJun CHEN JianMei LI JianMin College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology) Nanjing Universityof Posts and TelecommunicationsNanjing 210023China Department of Pathology College of Medicine University of CincinnatiCincinnatiOH 45267USA

The rapid development of portable and wearable electronic devices is responding to the urgent demand for high-efficiency flexible energy storage devices.Flexible supercapacitors,showing long cycle life,high power density,and good safety,are considered ideal candidates.Nevertheless,the relatively low energy density restricts their practical applications.With a large dielectric constant of 18-46,Ta_(2)O_(5)-based materials typically exhibit excellent electron-binding ability,which is critical for enhancing the energy density of supercapacitors.In this work,the free-standingβ-Ta_(2)O_(5)/single-walled carbon nanotubes(SWCNTs)composite film was prepared,with a highβ-Ta_(2)O_(5)loading of over 70%.By anchoringβ-Ta_(2)O_(5)nanoparticles onto the surface of SWCNTs,the system’s flexibility and conductivity were significantly enhanced,which also facilitated the intercalation electrodynamics of metal cations.As a result,the flexibleβ-Ta_(2)O_(5)/SWCNTs film exhibits excellent Li-ion storage performance,with a high volumetric specific capacitance of 392.3 F cm^(-3)at the scan rate of 10 mV s^(-1)and 198.9 F cm^(-3)at 500 mV s^(-1).In addition,the asymmetric device,assembled by theβ-Ta_(2)O_(5)/SWCNTs and activated carbon films,shows a high energy density of 45.5 Wh kg^(-1)at the power density of 10.8 kW kg^(-1).This technique opens up a new avenue for improving the energy density and rate performance of flexible supercapacitors.

关键词： pseudocapacitor Li-ion storage β-Ta_(2)O_(5)/SWCNTs film flexible device high-rate capability

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Pseudomonas aeruginosa regulator PvrA binds simultaneously to multiple pseudo-palindromic sites for efficient transcription activation

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Science China(Life Sciences) 2024年第5期67卷 900-912页

作者： Yibo zhu Bingnan Luo xingyu Mou Yingjie Song Yonghong Zhou Yongbo Luo Bo Sun Youfu Luo Hong Tang Zhaoming Su Rui Bao Center of Infectious Diseases Division of Infectious Diseases in State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengdu 610041China Department of Geriatrics and National Clinical Research Center for Geriatrics West China HospitalSichuan UniversityChengdu 610041China Key Laboratory of Biodiversity and Environment on the Qinghai-Tibetan Plateau Ministry of EducationSchool of Ecology and EnvironmentTibet UniversityLhasa 850000China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China College of Life Science Sichuan Normal UniversityChengdu 610101China Accurate Biotechnology(Hunan)Co. LtdChangsha 410006China

Tetracycline repressor(TetR)family regulators(TFRs)are the largest group of DNA-binding transcription factors and are widely distributed in bacteria and archaea.TFRs play vital roles in controlling the expression of various genes and regulating diverse physiological processes.Recently,a TFR protein Pseudomonas virulence regulator A(PvrA),was identified from Pseudomonas aeruginosa as the transcriptional activator of genes involved in fatty acid utilization and bacterial virulence.Here,we show that PvrA can simultaneously bind to multiple pseudo-palindromic sites and upregulate the expression levels of target genes.Cryo-electron microscopy(cryo-EM)analysis indicates the simultaneous DNA recognition mechanism of PvrA and suggests that the bound DNA fragments consist of a distorted B-DNA double helix.The crystal structure and functional analysis of PvrA reveal a hinge region that secures the correct domain motion for recognition of the promiscuous promoter.Additionally,our results showed that mutations disrupting the regulatory hinge region have differential effects on biofilm formation and pyocyanin biosynthesis,resulting in attenuated bacterial virulence.Collectively,these findings will improve the understanding of the relationship between the structure and function of the TetR family and provide new insights into the mechanism of regulation of P.aeruginosa virulence.

关键词： Pseudomonas aeruginosa transcription regulator TetR protein-structure virulence

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An Energy Stable SPH Method for Incompressible Fluid Flow

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Advances in Applied Mathematics and Mechanics 2022年第5期14卷 1201-1224页

作者： xingyu zhu Shuyu Sun Jisheng Kou Computational Transport Phenomena Laboratory Division of Physical Science and EngineeringKing Abdullah University of Science and TechnologyThuwal 23955-6900Saudi Arabia School of Civil Engineering Shaoxing UniversityShaoxing 312000ZhejiangChina School of Mathematics and Statistics Hubei Engineering UniversityXiaogan 432000HubeiChina

In this paper,a novel unconditionally energy stable Smoothed Particle Hydrodynamics(SPH)method is proposed and implemented for incompressible fluid flows.In this method,we apply operator splitting to break the momentum equation into equations involving the non-pressure term and pressure term separately.The idea behind the splitting is to simplify the calculation while still maintaining energy stability,and the resulted algorithm,a type of improved pressure correction scheme,is both efficient and energy stable.We show in detail that energy stability is preserved at each full-time step,ensuring unconditionally numerical stability.Numerical examples are presented and compared to the analytical solutions,suggesting that the proposed method has better accuracy and stability.Moreover,we observe that if we are interested in steady-state solutions only,our method has good performance as it can achieve the steady-state solutions rapidly and accurately.

关键词： Particle method Smoothed Particle Hydrodynamics(SPH)method incompressible fluid flow energy stability numerical stability

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Automatic Sensing and Detection for Subway Tunnel Pathologies

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Journal of World Architecture 2024年第1期8卷 54-62页

作者： xingyu Wang Zhengkun zhu School of Geomatics and Urban Spatial Informatics Beijing University of Civil Engineering and ArchitectureBeijing 102616China

Subway tunnels often suffer from surface pathologies such as cracks,corrosion,fractures,peeling,water and sand infiltration,and sudden hazards caused by foreign object intrusions.Installing a mobile visual pathology sensing system at the front end of operating trains is a critical measure to ensure subway safety.Taking leakage as the typical pathology,a tunnel pathology automatic visual detection method based on Deeplabv3+(ASTPDS)was proposed to achieve automatic and high-precision detection and pixel-level morphology extraction of pathologies.Compared with similar methods,this approach showed significant advantages and achieved a detection accuracy of 93.12%,surpassing FCN and U-Net.Moreover,it also exceeded the recall rates for detecting leaks of FCN and U-Net by 8.33%and 8.19%,respectively.

关键词： Visual detection Neural network Health monitoring Image segmentation Water leakage Subway tunnel.

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Beyond 600G fiber-THz wireless seamless integration system employing cascaded MIMO equalizers

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Science China Technological Sciences 2024年第7期67卷 2274-2276页

作者： DING JunJie TONG WeiDong LI XinTong ZHANG Zheng ZHANG Jiao CAI YuanCheng LEI MingZheng HUA BingChang CHEN xingyu YU JianJun zhu Min Purple Mountain Laboratories National Mobile Communications Research Laboratory Southeast University Fudan University

Terahertz(THz)-wave communication, with sufficient spectrum resources(0.3 THz～10 THz), can meet the needs of future 6G large-capacity mobile communication services[1-9]. Recently, the seamless integration of existing...

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基于复合神经网络的多源气动数据建模

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西北工业大学学报 2024年第2期42卷 328-334页

作者：朱星谕梅立泉西安交通大学数学与统计学院陕西西安710049

将深度学习方法应用至气动数据建模,能够解决传统建模方法效率低、代价高的问题,具有重要的现实意义。基于复合神经网络模型对多源气动数据进行学习,利用低精度数据辅助高精度数据进行预测。与不同网络模型进行对比,验证了文中提出的复... 详细信息

将深度学习方法应用至气动数据建模,能够解决传统建模方法效率低、代价高的问题,具有重要的现实意义。基于复合神经网络模型对多源气动数据进行学习,利用低精度数据辅助高精度数据进行预测。与不同网络模型进行对比,验证了文中提出的复合神经网络在气动数据建模中表现优良,且泛化能力较好。

关键词：气动数据建模深度神经网络复合神经网络

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A model test on an open-cut tunnel structure under the effect of a stick-slip normal fault

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Railway Sciences 2022年第2期1卷 169-192页

作者： Zhiqiang Zhang xingyu zhu Ronghua Wei School of Civil Engineering Southwest Jiaotong UniversityChengduChina Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengduChina

Purpose–Large displacement misalignment under the action of active faults can cause complex threedimensional deformation in subway tunnels,resulting in severe damage,distortion and misalignment.There is no developed system of fortification and related codes to follow.There are scientific problems and technical challenges in this field that have never been encountered in past research and practices.Design/methodology/approach–This paper adopted a self-designed large-scale active fault dislocation simulation loading system to conduct a similar model test of the tunnel under active fault dislocation based on the open-cut tunnel project of the Urumqi Rail Transit Line 2,which passes through the Jiujiawan normal fault.The test simulated the subway tunnel passing through the normal fault,which is inclined at 608.This research compared and analyzed the differences in mechanical behavior between two types of lining section:the opencut double-line box tunnel and the modified double-line box arch tunnel.The structural response and failure characteristics of the open-cut segmented lining of the tunnel under the stick-slip part of the normal fault were studied.Findings–The results indicated that the double-line box arch tunnel improved the shear and longitudinal bending performance.Longitudinal cracks were mainly distributed in the baseplate,wall foot and arch foot,and the crack position was basically consistent with the longitudinal distribution of surrounding rock pressure.This indicated that the longitudinal cracks were due to the large local load of the cross-section of the structure,leading to an excessive local bending moment of the structure,which resulted in large eccentric failure of the lining and formation of longitudinal cracks.Compared with the ordinary box section tunnel,the improved double-line box arch tunnel significantly reduced the destroyed and damage areas of the hanging wall and footwall.The damage area and crack length were reduced by 39 and 59.3%,respectively.This indicates that the improved double-li

关键词： Normal fault Stick-slip Open-cut tunnel Model test Failure characteristics

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Observational evidences of wave excitation and inverse cascade in a distant Earth foreshock region

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Science China Earth Sciences 2019年第4期62卷 619-630页

作者： Jiansen HE Die DUAN xingyu zhu Limei YAN Linghua WANG School of Earth and Space Sciences Peking University Key Laboratory of Earth and Planetary Physics Institute of Geology and Geophysics Chinese Academy of Sciences

The foreshock with nascent plasma turbulence is regarded as a fascinating region to understand basic plasma physical processes, e.g., wave-particle interactions as well as wave-wave couplings. Although there have been plenty of intensive studies on this topic, some key clues about the physical processes still lack observations. A relatively comprehensive case study with some new observations is presented in this work based on the WIND spacecraft observations. In this case, upstream energetic protons were drifting at tens of Alfvén speed with respect to the background plasma protons. When looking at the magnetic wave activities, we find the co-existence of high-frequency(0.1-0.5 Hz) large-amplitude right-hand polarized(RHP) waves and lowfrequency(0.02-0.1 Hz) small-amplitude left-hand polarized(LHP) waves in the spacecraft(SC) frame. The observed anticorrelation between magnetic and velocity fluctuations along with the sunward magnetic field direction indicates that the lowfrequency LHP waves in the SC frame are in fact the sunward upstream RHP Alfvénic waves in the solar wind frame. This new observation corroborates the applicability of theories about plasma non-resonance instability and inverse cascade to the foreshock region, where the downstream high-frequency RHP parent waves are excited by the upstream energetic protons through non-resonance instability and the low-frequency RHP daughter waves are generated by the parent waves due to nonlinear parametric instability. Furthermore, enhanced downstream energetic proton fluxes are inferred to result from scattering of the upstream protons by the nascent turbulent fluctuations. Therefore, some critical clues about the newborn turbulence in the foreshock are provided in this work.

关键词： Solar wind Foreshock Wave-particle interaction Parametric instability

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