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Earthquake Engineering and Engineering Vibration 2023年第4期22卷 965-977页

作者： Zhang Panpan Zhang lei Zhang zhen School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan 430070China

The performance of clay-pile-pier system under earthquake shaking was comprehensively examined via three-dimensional finite element analyses,in which the complex stress-strain relationships of a clay and piled pier system were depicted by a hyperbolic-hysteretic and an equivalent elastoplastic model,*** hundred twenty ground motions with varying peak accelerations were considered,along with the variations in bridge superstructure mass and pile flexural *** comparison studies suggested that peak pile-cap acceleration and peak pile-cap velocity are the optimal ground motion intensity measures for seismic responses of the pier and the pile,***,based on two optimal ground motion intensity measures and using curvature ductility to quantify different damage states,seismic fragility analyses were *** pier generally had no evident damage except when the bridge girder mass was equal to 960 t,which seemed to be comparatively insensitive to the varying pile flexural *** comparison,the pile was found to be more vulnerable to seismic damage and its failure probabilities tended to clearly reduce with the increment of pile flexural rigidity,while the influence of the bridge girder mass was relatively minor.

关键词： clay-pile-pier system seismic fragility analysis ground motion intensity measures damage probability

On scaling invariance and type-Ⅰ singularities for the compressible Navier-Stokes equations

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Science China Mathematics 2019年第11期62卷 2271-2286页

作者： zhen lei Zhouping Xin School of Mathematical Sciences LMNS and Shanghai Key Laboratory for Contemporary Applied MathematicsFudan UniversityShanghai 200433China The Institute of Mathematical Sciences and Department of Mathematics The Chinese University of Hong KongHong KongChina

We find a new scaling invariance of the barotropic compressible Navier-Stokes equations. Then it is shown that type-Ⅰ singularities of solutions with■ can never happen at time T for all adiabatic number γ 1. Here κ > 0 does not depend on the initial *** is achieved by proving the regularity of solutions under■ This new scaling invariance also motivates us to construct an explicit type-Ⅱ blowup solution for γ > 1.

关键词： type-Ⅰ singularity compressible Navier-Stokes equations scaling invariance blowup rate

Aircraft Observations of Liquid and Ice in Midlatitude Mixed-Phase Clouds

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Advances in Atmospheric Sciences 2014年第3期31卷 604-610页

作者： ZHAO zhen lei Hengchi Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric Physics Chinese Academy of Sciences

ABSTRACT This paper reports airborne measurements of midlatitude altostratus clouds observed over zhengzhou, Henan Province, China on 3 March 2007. The case demonstrates mixed-phase conditions at altitudes from 3200 to 4600 m （0°C to -7.6°C）, with liquid water content ranging from 0.01 to 0.09 g m-3. In the observed mixed-phase cloud, liquid water content exhibited a bimodal distribution, whereas the maximum ice particle concentration was located in the middle part of the cloud. The liquid and ice particle data showed significant horizontal variability on the scale of a few hundred meters. The cloud droplet concentration varied greatly over the horizontal sampling area. There was an inverse relationship between the cloud droplet concentration and ice particle concentration. A gamma distribution provided the best description of the cloud droplet spectra. The liquid droplet distributions were found to increase in both size and concentration with altitude. It was inferred from the profile of the spectra parameters that the cloud droplet sizes tend to form a quasi-monodisperse distribution. Ice particle spectra in the cloud were fitted well by an exponential distribution. Finally, a remarkable power law relationship was found between the slope （λ） and intercept （No） parameters of the exponential size distribution.

关键词： cloud structure liquid water content droplet spectra particle measuring systems

Spectroscopic properties of Er^(3+)-doped fluoroindate glasses

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Journal of Rare Earths 2022年第7期40卷 1037-1042页

作者： zhen Liu Jiangbo She Bo peng State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision MechanicsChinese Academy of Sciences(CAS)Xi'an 710119China University of Chinese Academy of Sciences(UCAS) Beijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

The optical and thermal properties of a new class of fluoroindate glass with different erbium contents were investigated via Raman,transmission,and fluorescence spectroscopies,fluorescence decay curve analysis,and differential scanning *** strength parameters of the samples were calculated using the Judd-Ofelt *** mid-infrared luminescence properties of erbium-doped fluoroindate glasses were studied,and a strong emission at 2.7μm was *** with the traditional ZBLAN glass,this glass has excellent emission properties,especially a longer fluorescence lifetime(7.09 ms)and larger emission cross-section(6.95×10^(-21) cm^(2))at 2.7μ*** results indicate that fluoroindate glass is an attractive host for mid-infrared lasers and as a gain medium for optical amplifier applications.

关键词： Optical materials Spectroscopic properties Luminescence Fluoroindate glasses Rare earths

Delineation of fatty acid metabolism in gastric cancer:Therapeutic implications

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World Journal of Clinical Cases 2023年第20期11卷 4800-4813页

作者： Yu Fu Bin Wang peng Fu lei Zhang Yi Bao zhen-zhen Gao Department of General Practice Medicine The Second affiliated hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina Department of Orthopeadic Oncology The Second Affiliated Hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina Department of Clinical Oncology The Second affiliated hospital of Jiaxing UniversityJiaxing 314000Zhejiang ProvinceChina

BACKGROUND The prognosis of gastric cancer is extremely *** reprogramming involving lipids has been associated with cancer occurrence and *** To illustrate fatty acid metabolic mechanisms in gastric cancer,detect core genes,develop a prognostic model,and provide treatment *** Raw data from The Cancer Genome Atlas and Gene Expression Omnibus databases were collected and *** expressed fatty acid metabolism genes were identified and incorporated into a risk model based on least absolute shrinkage and selection operator regression ***,patients from The Cancer Genome Atlas were assigned to high-and low-risk cohorts according to the mean value of the risk score as the threshold,which was verified in the Gene Expression Omnibus *** between chemotherapeutic sensitivity and tumor microenvironment features were *** An integrated evaluation was performed in this *** acid metabolismrelated genes were used to construct the risk *** classified into the high-risk cohort were considered to be resistant to chemotherapy based on results of the“pRRophetic”R *** in the high-risk cohort were associated with type Ⅰ/Ⅱ interferon activation,increased inflammation level,immune cell infiltration,and tumor immune dysfunction based on the exclusion algorithm,indicating the potential benefit of immunotherapy in these *** We constructed a fatty acid-related risk score model to assess the comprehensive fatty acid features in gastric cancer and validated its vital role in prognosis,chemotherapy sensitivity,and immunotherapy.

关键词： Stomach neoplasms Fatty acids Metabolism Risk assessment Immunotherapy

Ferromagnetic and ferroelectric two-dimensional materials for memory application

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Nano Research 2021年第6期14卷 1802-1813页

作者： zhen Liu Longjiang Deng Bo peng National Engineering Research Center of Electromagnetic Radiation Control Materials School of Electronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu611731China Key Laboratory of Multi-spectral Absorbing Materials and Structures of Ministry of Education University of Electronic Science and Technology of ChinaChengdu611731China State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu611731China

The discoveries of ferromagnetic and ferroelectric two-dimensional(2D)materials have dramatically inspired intense interests due to their potential in the field of spintronic and nonvolatile *** review focuses on the latest 2D ferromagnetic and ferroelectric materials that have been most recently studied,including insulating ferromagnetic,metallic ferromagnetic,antiferromagnetic and ferroelectric 2D *** fundamental properties that lead to the long-range magnetic orders of 2D materials are *** low Curie temperature(Tc)and instability in 2D systems limits their use in practical applications,and several strategies to address this constraint are proposed,such as gating and composition stoichiometry.A van der Waals(vdW)heterostructure comprising 2D ferromagnetic and ferroelectric materials will open a door to exploring exotic physical phenomena and achieve multifunctional or nonvolatile devices.

关键词： two-dimensional(2D)materials ferromagnetic ferroelectric heterostructure nonvolatile memory

On Li-Yau Heat Kernel Estimate

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Acta Mathematica Sinica,English Series 2021年第8期37卷 1205-1218页

作者： Lu LI zhen lei ZHANG School of Mathematics Capital Normal UniversityBeijing 100048P.R.China

We present some improvements of the Li-Yau heat kernel estimate on a Riemannian manifold with Ricci curvature bounded *** a consequence we prove a gradient estimate to the heat kernel with an optimal leading term.

关键词： Heat kernel Li-Yau estimate gradient estimate

A beam flexure-based nanopositioning stage supporting laser direct-write nanofabrication

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Science China(Physics,Mechanics & Astronomy) 2016年第8期59卷 50-55页

作者： zhen Zhang peng Wang peng Yan YingChun Guan State Key Laboratory of Tribology and Institute of Manufacturing Engineering Department of Mechanical EngineeringTsinghua University Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control Tsinghua University State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University Key Laboratory of High-efficiency and Clean Mechanical Manufacture Ministry of Education School of Mechanical EngineeringShandong University School of Automation Science and Electrical Engineering Beihang University School of Mechanical Engineering and Automation Beihang University

A nanopositioning system of both millimetric stroke and nanometric tracking accuracy is a key component for nanofabrication in many applications. In this paper, a novel bi-axial beam-flexure nano servo stage is proposed to support a direct writing system for femtosecond laser nanofabrication. The important features of the stage lie in: a mirror symmetric instead of rotational symmetric configuration is adopted to restrict cross axis coupling, and a novel Z-shaped guidance module is proposed to achieve relative large linear stiffness range, in addition a redundant constraints module is introduced to increase off-axis stiffness of the stage. Mechanical analysis and system identification are provided, with which a feedback control algorithm demonstrates the tracking capability for laser fabrication purposes. Based on the fabricated XY nano-stage, real time control and measurements are deployed, demonstrating the millimetric operating workspace and 77.8 nm(RMS) error of tracking a circular trajectory.

关键词： laser nanofabrication direct writing servo and control system

Van der Waals two-color infrared photodetector

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Light(Science & Applications) 2022年第2期11卷 179-187页

作者： Peisong Wu lei Ye lei Tong peng Wang Yang Wang Hailu Wang Haonan Ge zhen Wang Yue Gu Kun Zhang Yiye Yu Meng peng Fang Wang Min Huang peng Zhou Weida Hu State Key Laboratory of Infrared Physics Shanghai Institute of Technical PhysicsChinese Academy of SciencesShanghai 200083China University of Chinese Academy of Sciences Beijing 100049China Hubei Yangtze Memory Labs School of Optical and Electronic Information and Wuhan National Laboratory for OptoelectronicsHuazhong University of Science and TechnologyWuhanHubei 430205China State Key Laboratory of ASIC and Systems School of MicroelectronicsFudan UniversityShanghai 200433China

With the increasing demand for multispectral information acquisition,infrared multispectral imaging technology that is inexpensive and can be miniaturized and integrated into other devices has received extensive ***,the widespread usage of such photodetectors is still limited by the high cost of epitaxial semiconductors and complex cryogenic cooling ***,we demonstrate a noncooled two-color infrared photodetector that can provide temporal-spatial coexisting spectral blackbody detection at both near-infrared and mid-infrared *** photodetector consists of vertically stacked back-to-back diode *** two-color signals can be effectively separated to achieve ultralow crosstalk of~0.05%by controlling the built-in electric field depending on the intermediate layer,which acts as an electron-collecting layer and hole-blocking *** impressive performance of the two-color photodetector is verified by the specific detectivity(D^(*))of 6.4×10^(9)cm Hz^(1/2)W^(−1)at 3.5μm and room temperature,as well as the promising NIR/MWIR two-color infrared imaging and absolute temperature detection.

关键词： photodetector spectral absolute

短波长X射线衍射技术及在环境工程中的应用展望

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装备环境工程 2017年第6期14卷 43-48页

作者：郑林窦世涛张津肖勇何长光朱蕾彭正坤张鹏程封先河中国兵器工业第五九研究所重庆400039 北京科技大学材料科学与工程学院北京100083 中国工程物理研究院材料研究所四川绵阳621700

介绍了短波长特征X射线衍射无损检测分析原理和方法,无损地测定了预拉伸铝板、高强钢孔挤压件、铝合金搅拌摩擦焊接件等材料部件的内部残余应力、内部物相、内部织构及其分布,并分析讨论了测试结果。该仪器具有体积小,投资少、使用维护... 详细信息

介绍了短波长特征X射线衍射无损检测分析原理和方法,无损地测定了预拉伸铝板、高强钢孔挤压件、铝合金搅拌摩擦焊接件等材料部件的内部残余应力、内部物相、内部织构及其分布,并分析讨论了测试结果。该仪器具有体积小,投资少、使用维护方便等优势,展望了该无损检测分析技术在装备环境工程中的应用前景。

关键词：短波长特征X射线衍射内部残余应力内部织构内部物相环境试验