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Effect of grain structure on fatigue crack propagation behavior of Al-Cu-Li alloys

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Journal of Materials Science & Technology 2023年第17期148卷 75-89页

作者： Dingding Lu ben lin Tianle Liu Sanxi Deng Youjie Guo Jinfeng Li Danyang Liu School of Materials Science and Engineering Central South UniversityChangsha 410083China China Academy of Launch Vehicle Technology Beijing 100076China State Key Laboratory of Nonferrous Metals and Processes GRINM Group Co.LTD.Beijing 100088China Key Laboratory of Nonferrous Metal Materials Science and Engineering Ministry of EducationChangsha 410083China

Recrystallization behavior during optimized heat treatments provides a potential to obtain desirable grain structure,which significantly improves the mechanical properties of aluminum *** influence of grain structures on fatigue crack propagation(FCP)behaviors of Al-Cu-Li alloy with hot-rolled(HR)and cold-rolled(CR)was *** boundaries have a significant impact on small crack growth rates,which is reflected in the pronounced fluctuation of fatigue crack growth of HR specimens after solution ***,the specific cellular structure within grains can improve the deformation capacity of alloys due to their accommodation of plastic deformation,which contributes to the lower fatigue crack growth rates and higher threshold values in HR *** intragranular deflection also decelerates the FCP rate and occurs in these regions of large grain without subgrain *** occurs in the CR specimens,resulting in small anisotropy on the fatigue resistance for the different orientations in the Paris stage due to the recrystallization *** cracks can be deflected and tend to propagate along the grain boundaries when it goes into the grain with a relatively low Schmidt factor value.

关键词： Al-Cu-Li alloy Fatigue crack propagation Grain structure Microcrack

Research on the principle of space high-precision temperature control system of liquid crystals based Stokes polarimeter

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Research in Astronomy and Astrophysics 2021年第1期21卷 97-104页

作者： Xin-Wei Zhang Yang Zhang Jia-ben lin Jun-Feng Hou Yuan-Yong Deng Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of SciencesBeijing100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 101408China

The magnetic field is one of the most important parameters in solar physics,and a polarimeter is the key device to measure the solar magnetic *** crystals based Stokes polarimeter is a novel technology,and will be applied for magnetic field measurement in the first space-based solar observatory satellite developed by China,Advanced Space-based Solar ***,the liquid crystals based Stokes polarimeter in space is not a mature ***,it is of great scientific significance to study the control method and characteristics of the *** retardation produced by a liquid crystal variable retarder is sensitive to the temperature,and the retardation changes 0.09°per 0.10℃.The error in polarization measurement caused by this change is 0.016,which affects the accuracy of magnetic field *** order to ensure the stability of its performance,this paper proposes a high-precision temperature control system for liquid crystals based Stokes polarimeter in *** order to optimize the structure design and temperature control system,the temperature field of liquid crystals based Stokes polarimeter is analyzed by the finite element method,and the influence of light on the temperature field of the liquid crystal variable retarder is analyzed *** analyzing the principle of highprecision temperature measurement in space,a high-precision temperature measurement circuit based on integrated operational amplifier,programmable amplifier and 12 bit A/D is designed,and a high-precision space temperature control system is developed by applying the integral separation PI temperature control algorithm and PWM driving heating *** experimental results show that the effect of temperature control is accurate and stable,whenever the liquid crystals based Stokes polarimeter is either in the air or *** temperature stability is within±0.0150℃,which demonstrates greatly improved stability for the liquid crystals based Stokes polarim

关键词： liquid crystals based Stokes polarimeter high-precision temperature measurement space high-precision temperature control temperature field analysis PID control

Evolution of isolated G-band bright points: size, intensity and velocity

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Research in Astronomy and Astrophysics 2014年第6期14卷 741-752页

作者： Yun-Fei Yang Jia-ben lin Song Feng Kai-Fan Ji Hui Deng Feng Wang Faculty of Information Engineering and Automation/Yunnan Key Laboratory of Computer Technology Application Kunming University of Science and Technology Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Key Laboratory of Modern Astronomy and Astrophysics Nanjing University Ministry of Education

We study the evolution pattern of isolated G-band bright points （GBPs） in terms of their size, intensity and velocity. Using a high resolution image sequence taken with the Hinode/Solar Optical Telescope （SOT）, we detect GBPs in each image by the Laplacian and Morphological Dilation algorithm, and track their evolutions by a 26-adjacent method in a three-dimensional space-time cube. For quantifying the evolution, we propose a quantification method based on lifetime normalization which aligns the different lifetimes to common stages. The quantification results show that, on average, the diameter of isolated GBPs changes from 166 to 173 km, then down to 165 km; the maximum intensity contrast changes from 1.012 to 1.027, then down to 1.011; however, the velocity changes from 1.709 to 1.593 km s-1, then up to 1.703 km s-i. The results indicate that the evolution follows a pattern such that the GBP is small, faint and fast-moving at the birth stage, becomes big, bright and slow-moving at the middle stage, then gets small, faint and fast-moving at the decay stage until disappearance. Although the differences are very small, a two-sample t-test is used to demonstrate there are significant differences in means between the distri- butions of the different stages. Furthermore, we quantify the relationship between the lifetimes of GBPs and their properties. It is found that there are positive correlations between the lifetimes and their sizes and intensities with correlation coefficients of 0.83 and 0.65, respectively; however, there is a negative correlation between the life- times and velocities with a correlation coefficient of-0.49. In summary, the longer the GBP persists, the bigger, brighter and slower it will be.

关键词： techniques: image processing -- Sun: photosphere -- methods: dataanalysis -- methods: statistical

AN ELECTROCHEMICALLY PREPARED SKY-BLUE LIGHT EMITTING ETHER FUNCTIONALIZED POLYFLUORENE AS CHEMOSENSOR FOR METAL IONS

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Chinese Journal of Polymer Science 2013年第11期31卷 1579-1589页

作者： Wei Liu 孙明亮 Qian Liu ben-lin He Hong-lun Ge Miao Sun Qin-jie Zhang 王玮 Institute of Material Science and Engineering Ocean University of China

Synthesis and electrochemical polymerization of 9,9-bis（2-（2-（2-methoxy ethoxy）ethoxy）ethyl）-fluorene （EO-F） into poly[9,9-bis（2-（2-（2-methoxy ethoxy）ethoxy）ethyl）-fluorene] （EO-PF） films are reported. The boron trifluoride diethyl etherate electrolyte enables facile preparation of EO-PF films at lower potential compared to LiCIOa/MeCN and the electrochemical polymerizations are discussed. The EO-PF shows good electrochemical behavior and can be dissolved in solvents such as DMSO and THF. The solubility of EO-PF in THF is 2 ***-1 and the number average molecular weight is 35300 with a polydispersity index of 1.65. The side chains on C9 position of the monomer maintain unchanged aRer electrooxidation into corresponding polymer. The EO-PF dissolved in THF under 365 nm ultraviolet light is sky blue light emitting with the Commission Internationale de L＇Eclairage-CIE coordinates of （0.19, 0.15）. The electropolymerized EO-PF is used for the first time in chemosensing metal ions, demonstrating fluorescence quenching for Mn2＋ and Fe3＋ while fluorescence enhancement for Cr6＋ ions.

关键词： 9,9-Bis(2-(2-(2-methoxyethoxy)ethoxy)ethyl)-fluorene Boron trifluoride diethyl etherate Chemosensoryresponse Electrochemical polymerization.

Field validation of imaging an adjacent borehole using scattered P-waves

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Petroleum Science 2020年第5期17卷 1272-1280页

作者： Jian-lin ben Wen-Xiao Qiao Xiao-Hua Che Xiao-Dong Ju Jun-Qiang Lu Bai-Yong Men State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China Key Laboratory of Earth Prospecting and Information Technology Beijing 102249China

Acoustic waves enter a rock formation from a borehole and are reflected or scattered upon encountering a geologic ***,we obtain the structure location represented by the azimuth and distance from the borehole using the acoustic reflection or *** acoustic measurements with the azimuthal resolution are realized using an azimuthal acoustic receiver sonde composed of several arcuate phased array *** sensors distributed evenly across the arcuate phased array receiver can record acoustic waves independently;this allows us to adopt the beamforming *** use a supporting logging tool to conduct the downhole test in two adjacent fluid-filled boreholes,for validating the evaluation of the geologic structure using scattered *** test results show the multi-azimuth images of the target borehole and the azimuthal variation in scattering ***,we obtain the precise location of the target ***,the measured values of the target borehole are consistent with the actual values,indicating that we can accurately evaluate a near-borehole geologic structure with scattered P-waves.

关键词： Acoustic logging Acoustic imaging Scattering exploration Beamforming

Lossless Compression Method for the Magnetic and Helioseismic Imager(MHI)Payload

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Research in Astronomy and Astrophysics 2024年第4期24卷 214-221页

作者： Li-Yue Tong Jia-ben lin Yuan-Yong Deng Kai-Fan Ji Jun-Feng Hou Quan Wang Xiao Yang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Key Laboratory of Solar Activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Yunnan Observatories Chinese Academy of SciencesKunming 650216China

The Solar Polar-orbit Observatory(SPO),proposed by Chinese scientists,is designed to observe the solar polar regions in an unprecedented way with a spacecraft traveling in a large solar inclination angle and a small ***,one of the most significant challenges lies in ultra-long-distance data transmission,particularly for the Magnetic and Helioseismic Imager(MHI),which is the most important payload and generates the largest volume of data in *** this paper,we propose a tailored lossless data compression method based on the measurement mode and characteristics of MHI *** background out of the solar disk is removed to decrease the pixel number of an image under *** predictive coding methods are combined to eliminate the redundancy utilizing the correlation(space,spectrum,and polarization)in data set,improving the compression *** results demonstrate that our method achieves an average compression ratio of *** compression time is also less than the general observation *** method exhibits strong feasibility and can be easily adapted to MHI.

关键词： methods:data analysis techniques:image processing Sun:magnetic fields Sun:photosphere

Characterizing motion types of G-band bright points in the quiet Sun

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Research in Astronomy and Astrophysics 2015年第4期15卷 569-582页

作者： Yun-Fei Yang Hui-Xue Qu Kai-Fan Ji Song Feng Hui Deng Jia-ben lin Feng Wang Faculty of Information Engineering and Automation / Yunnan Key Laboratory of Computer Technology Application Kunming University of Science and Technology Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of Sciences Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityMinistry of Education Yunnan Observatories Chinese Academy of Sciences

We study the motion of G-band bright points （GBPs） in the quiet Sun to obtain the characteristics of different motion types. A high resolution image sequence taken with the Hinode/Solar Optical Telescope （SOT） is used, and GBPs are automat- ically tracked by segmenting 3D evolutional structures in a space-time cube. After putting the GBPs that do not move during their lifetimes aside, the non-stationary GBPs are categorized into three types based on an index of their motion type. Most GBPs that move in straight or nearly straight lines are categorized as a straight mo- tion type, a few moving in rotary paths into rotary motion, and the others fall into a motion type we called erratic. The mean horizontal velocities are 2.18±0.08 km s-1, 1.63±0.09km s^-1 and 1.33±0.07 km s^-1 for straight, erratic and rotary motion types, respectively. We find that a GBP drifts at a higher and constant velocity during its whole life if it moves in a straight line. However, it has a lower and variational velocity if it moves on a rotary path. The diffusive process is ballistic-, super- and sub-diffusion for straight, erratic and rotary motion types, respectively. The corresponding diffusion index （γ） and coefficients （K） are 2.13±0.09 and 850±37km^2 s^-1, 1.82±0.07 and 331 ±24 km^2 s^-1, and 0.73±0.19 and 13±9 km^2 s^-1. In terms of direction of motion, it is homogeneous and isotropic, and usually persists between neighboring frames, no matter what motion type a GBP is classified as.

关键词： techniques: image processing -- Sun: photosphere -- methods: dataanalysis -- methods: statistical

Exposure to PM2.5 Enhances the PI3K/AKT Signaling and Malignancy of ERα Expression-dependent Non-small Cell Lung Carcinoma

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Biomedical and Environmental Sciences 2021年第4期34卷 319-323页

作者： TIAN Lei LI Ying LIU Huan Liang LAI Wen Qing SHI Yue LIU Xiao Hua XI Zhu Ge lin ben Cheng Tianjin Institute of Environmental and Operational Medicine Tianjin 300050China The Third Surgical Department of Breast Cancer Tianjin Medical University Cancer Institute and HospitalTianjin 300070China

Atmospheric particulate matter(PM)2.5 is a major carcinogen and is associated with an increased risk of developing various cancers and pulmonary fibrous diseases[1-2].Non-small cell lung cancer(NSCLC)is the major type of lung cancer with high morbidity and mortality *** studies report that the incidence of NSCLC,particularly adenocarcinoma,significantly differs with the gender[3].Female patients with NSCLC have unique epidemiologic characteristics,imaging profiles,clinical manifestations,and pathological characteristics[4].

关键词： PI3K/AKT NSCLC ERα

Chiral Pair Density Waves with Residual Fermi Arcs in RbV_(3)Sb_(5)

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Chinese Physics Letters 2024年第9期41卷 88-92页

作者： Xiao-Yu Yan Hanbin Deng Tianyu Yang Guowei Liu Wei Song Hu Miao Zhijun Tu Hechang Lei Shuo Wang ben-Chuan lin Hailang Qin Jia-Xin Yin Department of Physics Southern University of Science and TechnologyShenzhen 518055China Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTennessee 37831USA Beijing Key Laboratory of Optoelectronic Functional Materials MicroNano Devices Department of PhysicsRenmin University of ChinaBeijing 100872China Key Laboratory of Quantum State Construction and Manipulation(Ministry of Education) Renmin University of ChinaBeijing 100872China Shenzhen Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Guangdong Provincial Key Laboratory of Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area Shenzhen 518055China

The chiral 2×2 charge order has been reported and confirmed in the kagome superconductor RbV_(3)Sb_(5),while its interplay with superconductivity remains elusive owing to its lowest superconducting transition temperature Tc of about 0.85K in the AV_(3)Sb_(5) family(A=K,Rb,Cs)that severely challenges electronic spectroscopic ***,utilizing dilution-refrigerator-based scanning tunneling microscopy down to 30 mK,we observe chiral 2×2 pair density waves with residual Fermi arcs in RbV_(3)Sb_(5).We find a superconducting gap of 150 μeV with substantial residual in-gap *** spatial distribution of this gap exhibits chiral 2×2 modulations,signaling a chiral pair density wave(PDW).Our quasi-particle interference imaging of the zero-energy residual states further reveals arc-like *** discuss the relation of the gap modulations with the residual Fermi arcs under the space-momentum correspondence between PDW and Bogoliubov Fermi states.

关键词： Fermi chiral utilizing