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Plasma Science and Technology 2024年第4期26卷 156-161页

作者：姚远杨曜提昂宋扬张家敏王琰张耀刘海庆揭银先 Institute of Plasma Physics Chinese Academy of SciencesHefei 230031People’s Republic of China Anhui Electrical Engineering Professional Technique College Hefei 230022People’s Republic of China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601People’s Republic of China

Electron density in fusion plasma is usually diagnosed using laser-aided interferometers. The phase difference signal obtained after phase demodulation is wrapped, which is also called a fringe jump. A method has been developed to unwrap the phase difference signal in real time using FPGA, specifically designed to handle fringe jumps in the hydrogen cyanide(HCN) laser interferometer on the EAST superconducting tokamak. This method is designed for a phase demodulator using the fast Fourier transform(FFT) method at the front end. The method is better adapted for hardware implementation compared to complex mathematical analysis algorithms, such as field programmable gate array(FPGA). It has been applied to process the phase measurement results of the HCN laser interferometer on EAST in real time. Electron density results show good confidence in the fringe jump unwrapping method. Further possible application in other laser interferometers, such as the POlarimeter-INTerferometer(POINT)system on EAST tokamak is also discussed.

关键词： electron density laser-aided interferometer fringe jump unwrapping FPGA EAST

Numerical simulation of the three-dimensional flow-path in a ram-rotor

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航空动力学报 2010年第6期25卷 1358-1365页

作者： HAN Ji-ang zhong Jing-jun YAN hong-ming Marine Engineering College Dalian Maritime UniversityDalian 116026China School of Energy Science and Engineering Harbin institute of TechnologyHarbin 150001China

A kind of three-dimensional flow-path of the ram-rotor was designed in this paper according to the design method of the typical supersonic intake of aircraft and missiles,especially the design method of the compression ramp,the throat and the subsonic *** design Mach number of the flow-path was based on the averaged relative Mach number,regardless of the change of incoming Mach number along radial direction of the ***,the flowfield of the designed flow-path was simulated numerically with computational fluid dynamics software at design *** purpose of simulation was to obtain the details of the flowfield,including the structure of the shock wave system,position of flow separation zone,and so *** performance of the ram-rotor was also *** numerical results show the structure of the shock wave system in the flow-path is similar to that in the supersonic *** improve the overall performance of the ram-rotor,the reasonable compromise between the total pressure ratio and the isentropic adiabatic efficiency should be *** structure optimization of the flow-path and the configuration of the shock wave system have great influence on the performance of the ram-rotor.

关键词： ram-rotor flow-path supersonic intake numerical simulation design point

Influence of angiotensin II on α₁-Adrenergic Receptors Function in Rat Aorta and Expression in Vascular Smooth Muscle Cells

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Journal of Biosciences and Medicines 2024年第4期12卷 123-134页

作者： Itzell Alejandrina Gallardo-Ortíz Juan Pablo de Jesús Benítez-Garrido Santiago C. Sigrist-Flores Juan Javier López-Guerrero Enrique hong Rafael Villalobos-Molina Unidad de Biomedicina Facultad de Estudios Superiores Iztacala Universidad Nacional Aut&#243noma de M&#233xico Tlalnepantla M&#233xico Carrera de Enfermerí a Facultad de Estudios Superiores Iztacala Universidad Nacional Aut&#243noma de M&#233xico Tlalnepantla M&#233xico Departamento de Farmacobiologí a Centro de Investigaci&#243n and de Estudios Avanzados-IPN Ciudad de M&#233xico M&#233xico Carrera de Mé dico Cirujano Facultad de Estudios Superiores Iztacala Universidad Nacional Aut&#243noma de M&#233xico Tlalnepantla M&#233xico

angiotensin II (ang II) is the main mediator of the Renin-angiotensin-System acting on AT1 and other AT receptors. It is regarded as a pleiotropic agent that induces many actions, including functioning as a growth factor, and as a contractile hormone, among others. The aim of this work was to examine the impact of ang II on the expression and function of α1-adrenergic receptors (α1-ARs) in cultured rat aorta, and aorta-derived smooth muscle cells. Isolated Wistar rat aorta was incubated for 24 h in DMEM at 37˚C, then subjected to isometric tension and to the action of added norepinephrine, in concentration-response curves. ang II was added (1 × 10−5 M), and in some experiments, 5-Methylurapidil (α1A-AR antagonist), AH11110A (α1B-AR antagonist), or BMY-7378 (α1D-AR antagonist), were used to identify the α1-AR involved in the response. Desensitization of the contractile response to norepinephrine was observed due to incubation time, and by the ang II action. α1D-AR was protected from desensitization by BMY-7378;while RS-100329 and prazosin partially mitigated desensitization. In another set of experiments, isolated aorta-derived smooth muscle cells were exposed to ang II and α1-ARs proteins were evaluated. α1D-AR increased at 30 and 60 min post ang II exposure, the α1A-AR diminished from 1 to 4 h, while α1B-AR remained unchanged over 24 h of ang II exposure. ang II induced an increase of α1D-AR at short times, and BMY-7378 protected α1D-AR from desensitization.

关键词： angiotensin II α1D-AR α1-AR Expression Rat aorta Smooth Muscle Cells

双层单原子催化剂用于促进高活性和选择性电催化硝酸盐还原制氨

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物理化学学报 2024年第6期40卷 60-62页

作者：于镜坤雍雪曹昂卢思宇郑州大学化学学院绿色催化中心郑州450001 Department of Chemistry University of SheffieldSheffieldS37HFUK Department of Physics Technical University of DenmarkKongens Lyngby 2800Denmar

高效、高选择性的单原子催化剂(SACs)在电催化硝酸盐还原制氨过程中具有重要作用。然而,由于中间体、金属活性中心和配位环境之间复杂的竞争性电子相互作用,仍然面临挑战。本研究采用密度泛函理论(DFT)计算,对27种SACs以及双层SACs(BSA... 详细信息

高效、高选择性的单原子催化剂(SACs)在电催化硝酸盐还原制氨过程中具有重要作用。然而,由于中间体、金属活性中心和配位环境之间复杂的竞争性电子相互作用,仍然面临挑战。本研究采用密度泛函理论(DFT)计算,对27种SACs以及双层SACs(BSACs)进行了系统研究,通过轴向d-d轨道杂化提高了从SACs到BSACs的电催化硝酸盐还原反应(NO_(3)RR)的活性和选择性。考虑到可能的O端、N端、NO端和NO二聚体途径,计算结果显示,在单层SACs中,Ti-Pc和V-Pc分别具有优异的极限电位(U_(L)),分别为-0.24和-0.48V。形成能、溶解势以及从头算分子动力学结果表明,在反应条件下,这些催化剂非常稳定。在这些单层TM-Pc中,它们的d带能级和占据数受到d_(xz)/d^(yz)和p_(z)轨道杂化的影响。其轴向d_(z^(2))轨道的可用性通过形成d_(z^(2))-d_(z^(2))相互作用来进一步调整d带和反应性。在此基础上,以Ti-Pc和V-Pc为底物,通过形成轴向d-d轨道杂化来构建BSACs,为调节NO_(3)RR催化性能提供了一种独特的新途径。重要的是,我们发现d带中心(εd)、d_(xz)+d_(yz)轨道的占据数和U_(L)之间存在二维火山关系,用于描述它们的NO_(3)RR催化性能。最佳的BSACs应该同时具备适当的ε_(d)和d_(xz)+d_(yz)占用数。Ti-Mo和Ti-Ta被确定为出色的NO_(3)RR催化剂,其U_(L)均降低至-0.13 V。而d_(z^(2))-d_(z^(2))轨道之间的杂化则增强了双层金属之间的电荷转移和结构稳定性。缺乏相邻的金属位点将导致生成NO_(2)、NO和N_(2)的能垒较高,从而抑制副产物生成。最终,本研究揭示了在SACs和BSACs上对硝酸盐还原进行合理优化的方法,可为改进电催化剂的设计提供指导。

关键词：硝酸盐还原第一性原理计算单原子催化剂双层单原子催化剂轴向轨道杂化

Bound states in the continuum based on the total internal reflection of Bloch waves

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National Science Review 2023年第1期10卷 178-186页

作者： Peng Hu Chongwu Xie Qianju Song ang Chen hong Xiang Dezhuan Han Jian zi College of Physics Chongqing University State Key Laboratory of Surface Physics Key Laboratory of Microand Nano-Photonic Structures (Ministry of Education) and Department of Physics Fudan University Chongqing Key Laboratory for Strongly Coupled Physics

A photonic-crystal slab can support bound states in the continuum(BICs) that have infinite lifetimes but are embedded into the continuous spectrum of optical modes in free *** formation of BICs re quires a total internal reflection(TIR) condition at both interfaces between the slab and the free ***,we show that the TIR of Bloch waves can be directly obtained based on the generalized Fresnel equations *** each of these Bloch waves picks up a phase with integer multiples of 2π for traveling a round trip,light can be perfectly guided in the slab,namely forming a BIC.A BIC solver with low computational complexity and fast convergence speed is developed,which can also work efficiently at high frequencies beyond the diffraction limit where multiple radiation channels *** examples of multi-channel BICs are shown and their topological nature in momentum space is also *** can be attributed to the coincidence of the topological charges of far-field radiations from different radiation *** concept of the generalized TIR and the TIR-based BIC solver developed offer highly effective approaches for explorations of BICs that could have many potential applications in guided-wave optics and enhanced light-matter interactions.

关键词： bound states in the continuum total internal reflection Bloch waves generalized Fresnel equations topological charges

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基于宽度自编码网络的单分类集成算法

信号处理 2024年第4期40卷 776-788页

作者：施一帆陈宇昂曾焕强杨楷翔华侨大学工学院福建泉州362021 华南理工大学计算机科学与工程学院广东广州510006 计算机软件新技术国家重点实验室江苏南京210023

异常检测是模式识别领域的经典研究,然而在极端类别不平衡场景下,异常样本匮乏,训练数据仅包含正常样本,传统异常检测方法难以适用。因此,单分类算法逐渐受到关注,它只使用目标类样本构建决策边界,实现对非目标类样本的识别。目前单分... 详细信息

异常检测是模式识别领域的经典研究,然而在极端类别不平衡场景下,异常样本匮乏,训练数据仅包含正常样本,传统异常检测方法难以适用。因此,单分类算法逐渐受到关注,它只使用目标类样本构建决策边界,实现对非目标类样本的识别。目前单分类算法已经取得了显著进展,然而也存在一些局限性:(1)原始特征空间容易受噪声特征干扰;(2)单模型的单分类算法难以从多个特征空间学习更全面的决策边界;(3)缺少对先前模型的欠拟合样本进行针对性学习。为了解决这些问题,本文提出了基于宽度自编码网络的单分类集成算法(Ensemble One-class Classification Based on BLS-Autoencoder,EOC-BLSAE)。首先,本文设计了一种单分类宽度自编码网络模型(One-class BLS-Autoencoder,OC-BLSAE),它能高效学习原始特征空间到重构特征空间的非线性映射关系,利用重构误差构建决策边界;接着,本文设计了单分类Boosting策略,通过最小化全局重构损失,迭代学习欠拟合样本,从而多角度构建OC-BLSAE模型,并自适应评估模型的可靠性;最终,加权集成多个OC-BLSAE模型,有效提升整体算法准确性和鲁棒性。在实验中,本文在16个不同规模的单分类任务上进行参数实验、对比实验和消融实验,结果表明所提算法参数选择较为灵活,算法各模块能够相互协同,有效提升单分类任务的准确性和鲁棒性,整体性能超过前沿单分类方法。

关键词：单分类异常检测宽度学习系统集成学习

基于多位移光谱遥感图像的空间引力模型亚像元定位

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哈尔滨工程大学学报 2024年第6期45卷 1179-1186页

作者：王鹏严昂陈永康赵春雷石立新中国测绘科学研究院测绘科学与地球空间信息技术自然资源部重点实验室北京100039 湖南省国土资源规划院自然资源部南方丘陵区自然资源监测监管重点实验室湖南长沙410114 南京航空航天大学电子信息工程学院江苏南京211106 河北省气象科学研究所河北省气象与生态环境重点实验室河北石家庄050022

目前基于多位移光谱遥感图像的亚像元定位方法通常很少考虑点扩散函数效应影响,本文提出了一种基于多位移光谱遥感图像的空间引力模型亚像元定位方法。为了生成粗糙丰度图像,首先对多个多位移光谱遥感图像进行解混;在点扩散函数效应被... 详细信息

目前基于多位移光谱遥感图像的亚像元定位方法通常很少考虑点扩散函数效应影响,本文提出了一种基于多位移光谱遥感图像的空间引力模型亚像元定位方法。为了生成粗糙丰度图像,首先对多个多位移光谱遥感图像进行解混;在点扩散函数效应被考虑的前提下,对粗糙丰度图像实施面积到点的克里插值处理,然后通过理想方波滤波进行滤波,最终获得改进后的粗糙丰度图像;利用空间引力模型对改进后的粗糙丰度图像进行上采样,从而得到上采样丰度图像,再对上采样丰度图像执行整合处理,以生成精细丰度图像;在完成上述所有图像处理步骤后,最终通过应用类别分配方法,将类别标签分发给各个亚像元,以此获得精确的定位结果。在2组实验数据集上的实验结果表明:本文提出的方法比现有的亚像元定位方法获得了更好的定位效果。

关键词：遥感图像高光谱图像亚像元定位点扩散函数空间引力模型多位移光谱遥感图像

Refining constitutive relation by integration of finite element simulations and Gleeble experiments

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Journal of Materials Science & Technology 2019年第6期35卷 1039-1043页

作者： D.J. Yu D.S. Xu H. W ang z.B. zhao G.z. Wei R. Yang College of Sciences Northeastern University Shenyang 110004 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Thermo-mechanical coupled finite element calculations were carried out to simulate the Gleeble compression of the samples of a titanium alloy(Ti60), and the results are analyzed and compared with the actual compression tests conducted on a Gleeble 3800 thermo-mechanical simulator. The changes in temperature, stress and strain distribution in the samples and the source of error on the constitutive relations from Gleeble hot compression test were analyzed in detail. Both simulations and experiments showed that the temperature distribution in the specimen is not uniform during hot compression, resulting in significant deformation inhomogeneity and non-ignorable error in the flow stress strain relation,invalidating the uniform strain assumption commonly assumed when extracting the constitutive relation from Gleeble tests. Based on the finite element simulations with iterative corrections, we propose a scheme to refine the constitutive relations from Gleeble tests.

关键词： Titanium alloy Constitutive relation Finite element Compression Temperature distribution

Gradient Structured Copper by Rotationally Accelerated Shot Peening

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Journal of Materials Science & Technology 2017年第7期33卷 758-761页

作者： X.Wang Y.S.Li Q.z.ang Y.H.zhao Y.T.zhu Nano Structural Materials Center School of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China School of Mechanical Engineering Nanjing University of Science and Technology Nanjing 210094 China Department of Materials Science and Engineering North Carolina State University Raleigh NC 27695 USA

A new technology-rotationally accelerated shot peening（RASP）, was developed to prepare gradient structured materials. By using centrifugal acceleration principle and large steel balls, the RASP technology can produce much higher impact energy compared to conventional shot peening. As a proof-of-concept demonstration, the RASP was utilized to refine the surface layer in pure copper（Cu） with an average grain size of 85 nm. The grain size increases largely from surface downwards the bulk, forming an800 ？m thick gradient-structured surface layer and consequently a micro-hardness gradient. The difference between the RASP technology and other established techniques in preparing gradient structured materials is discussed. The RASP technology exhibits a promoting future for large-scale manufacturing of gradient materials.

关键词： Microstructure Rotationally accelerated shot peening Gradient structure Hardness Copper

STCF conceptual design report (Volume 1): Physics & detector

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Frontiers of physics 2024年第1期19卷 1-154页

作者： M.Achasov X.C.Ai L.P.An R.Aliberti Q.An X.z.Bai Y.Bai O.Bakina A.Barnyakov V.Blinov V.Bobrovnikov D.Bodrov A.Bogomyagkov A.Bondar I.Boyko z.H.Bu F.M.Cai H.Cai J.J.Cao Q.H.Cao X.Cao z.Cao Q.Chang K.T.Chao D.Y.Chen H.Chen H.X.Chen J.F.Chen K.Chen L.L.Chen P.Chen S.L.Chen S.M.Chen S.Chen S.P.Chen W.Chen X.Chen X.F.Chen X.R.Chen Y.Chen Y.Q.Chen H.Y.Cheng J.Cheng S.Cheng T.G.Cheng J.P.Dai L.Y.Dai X.C.Dai D.Dedovich A.Denig I.Denisenko J.M.Dias D.z.Ding L.Y.Dong W.H.Dong V.Druzhinin D.S.Du Y.J.Du z.G.Du L.M.Duan D.Epifanov Y.L.Fan S.S.Fang z.J.Fang G.Fedotovich C.Q.Feng X.Feng Y.T.Feng J.L.Fu J.Gao Y.N.Gao P.S.Ge C.Q.Geng L.S.Geng A.Gilman L.Gong T.Gong B.Gou W.Gradl J.L.Gu A.Guevara L.C.Gui A.Q.Guo F.K.Guo J.C.Guo J.Guo Y.P.Guo z.H.Guo A.Guskov K.L.Han L.Han M.Han X.Q.Hao J.B.He S.Q.He X.G.He Y.L.He z.B.He z.X.Heng B.L.Hou T.J.Hou Y.R.Hou C.Y.Hu H.M.Hu K.Hu R.J.Hu W.H.Hu X.H.Hu Y.C.Hu J.Hua G.S.Huang J.S.Huang M.Huang Q.Y.Huang W.Q.Huang X.T.Huang X.J.Huang Y.B.Huang Y.S.Huang N.Hüsken V.Ivanov Q.P.Ji J.J.Jia S.Jia z.K.Jia H.B.Jiang J.Jiang S.z.Jiang J.B.Jiao z.Jiao H.J.Jing X.L.Kang X.S.Kang B.C.Ke M.Kenzie A.Khoukaz I.Koop E.Kravchenko A.Kuzmin Y.Lei E.Levichev C.H.Li C.Li D.Y.Li F.Li G.Li G.Li H.B.Li H.Li H.N.Li H.J.Li H.L.Li J.M.Li J.Li L.Li L.Li L.Y.Li N.Li P.R.Li R.H.Li S.Li T.Li W.J.Li X.Li X.H.Li X.Q.Li X.H.Li Y.Li Y.Y.Li z.J.Li H.Liang J.H.Liang Y.T.Liang G.R.Liao L.z.Liao Y.Liao C.X.Lin D.X.Lin X.S.Lin B.J.Liu C.W.Liu D.Liu F.Liu G.M.Liu H.B.Liu J.Liu J.J.Liu J.B.Liu K.Liu K.Y.Liu K.Liu L.Liu Q.Liu S.B.Liu T.Liu X.Liu Y.W.Liu Y.Liu Y.L.Liu z.Q.Liu z.Y.Liu z.W.Liu I.Logashenko Y.Long C.G.Lu J.X.Lu N.Lu Q.F.Lü Y.Lu Y.Lu z.Lu P.Lukin F.J.Luo T.Luo X.F.Luo Y.H.Luo H.J.Lyu X.R.Lyu J.P.Ma P.Ma Y.Ma Y.M.Ma F.Maas S.Malde D.Matvienko z.X.Meng R.Mitchell A.Nefediev Y.Nefedov S.L.Olsen Q.Ouyang P.Pakhlov G.Pakhlova X.Pan Y.Pan E.Passemar Y.P.Pei H.P.Peng L.Peng X.Y.Peng X.J.Peng K.Peters S.Pivovarov E.Pyata B.B.Qi Y.Q.Qi W.B.Qian Y.Qian C.F.Qiao J.J.Qin J.J.Qin L.Q.Qin X.S.Qin T.L.Qiu J.Rademacker C.F.Redmer H.Y.Sang Anhui University Hefei 230039China Beihang University Beijing 100191China Budker Institute of Nuclear Physics Novosibirsk 630090Russia CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Cavendish Laboratory University of CambridgeJJ Thomson AveCambridge CB30HEUnited Kingdom Central China Normal University Wuhan 430079China Central South University Changsha 410083China China University of Geosciences Wuhan 430074China China University of Mining and Technology Xuzhou 221116China École Polytechnique Fédérale de Lausanne(EPFL) LausanneSwitzerland Fudan University Shanghai 200433China Goethe University Frankfurt D-60325 Frankfurt am MainGermany Guangxi Normal University Guilin 541004China Guangxi Uninversity Nanning 530004China Hangzhou Institute for Advanced Study UCASHangzhou 310024China Hebei Normal University Shijiazhuang 050024China Hebei University Baoding 071002China Hefei University of Technology Hefei 230601China Helmholtz Institute Mainz Staudinger Weg 18D-55099 MainzGermany Henan Normal University Xinxiang 453007China Henan University Kaifeng 475004China High Energy Physics Center Chung-Ang UniversitySeoul 06974Korea Higher School of Economy 11 Pokrovsky Bulvar Moscow 109028Russia Huangshan University Huangshan 245000China Hubei University of Automotive Technology Shiyan 442002China Hunan Normal University Changsha 410081China Hunan University of Science and Technology Xiangtan 411201China Hunan University Changsha 410082China Indiana University BloomingtonIndiana 47405USA Inner Mongolia University Hohhot 010021China Institute of Advanced Science Facilities Shenzhen 518107China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Institute of Physics Academia SinicaTaipeiTaiwan 11529China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China Jilin University Changch

The superτ-charm facility(STCF)is an electron–positron collider proposed by the Chinese particle physics *** is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5×10^(35) cm^(–2)·s^(–1) or *** STCF will produce a data sample about a factor of 100 larger than that of the presentτ-charm factory—the BEPCII,providing a unique platform for exploring the asymmetry of matter-antimatter(charge-parity violation),in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions,as well as searching for exotic hadrons and physics beyond the Standard *** STCF project in China is under development with an extensive R&D *** document presents the physics opportunities at the STCF,describes conceptual designs of the STCF detector system,and discusses future plans for detector R&D and physics case studies.

关键词： electron–positron collider tau-charm region high luminosity STCF detector conceptual design