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第一性原理研究钛合金中的沉淀强化

金属学报 2024年第4期60卷 537-547页

作者：程坤陈树明曹烁刘建荣马英杰范群波程兴旺杨锐胡青苗中国科学院金属研究所师昌绪先进材料创新中心沈阳110016 中国科学技术大学材料科学与工程学院沈阳110016 北京理工大学材料学院冲击环境材料技术重点实验室北京100081

为研究合金化对沉淀强化行为的影响,采用第一性原理方法计算了二元Ti-xM(M=Al、V、Cr、Mn、Fe、Co、Ni、Zr、Nb、Mo、Ta、W)合金弹性模量随成分的变化,提出了弹性模量Mo当量概念,以高效计算复杂成分钛合金(如Ti-Al-V合金以及Ti55521)的... 详细信息

为研究合金化对沉淀强化行为的影响,采用第一性原理方法计算了二元Ti-xM(M=Al、V、Cr、Mn、Fe、Co、Ni、Zr、Nb、Mo、Ta、W)合金弹性模量随成分的变化,提出了弹性模量Mo当量概念,以高效计算复杂成分钛合金(如Ti-Al-V合金以及Ti55521)的弹性模量;结合弹性模量及Russell-Brown沉淀强化模型,研究了二元Ti-xM(M=V、Cr、Mn、Fe、Co、Ni、Nb、Mo、Ta、W)合金以及Ti55521合金中的沉淀强化。结果显示,在体积分数及沉淀相颗粒尺寸相同的情况下,Co、Fe、W、Mo、Ni、Mn沉淀强化作用较强,Cr、Nb、Ta强化作用居中,V强化作用最弱。随合金元素含量x增加,沉淀强化作用均有所增强。热机械处理Ti55521合金经短时时效后,沉淀强化作用有所减弱,但长时时效后,沉淀强化效果增强。

关键词：第一性原理钛合金弹性模量沉淀强化强度

慢性萎缩性胃炎组织病理学表现与内镜检查结果的差异性分析

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临床与病理杂志 2024年第5期44卷 674-680页

作者：贺祥凤曹烁彭依罗举长沙市中心医院老年医学科长沙410004 中南大学湘雅三医院消化内科长沙410013

目的:部分患者的组织病理学表现符合慢性萎缩性胃炎,而相应的内镜检查却没有报告慢性萎缩性胃炎。本研究拟将组织病理学表现符合萎缩和肠化生的患者作为研究的目标人群,探讨这部分人群的临床特征、病理结果与内镜检查的符合率,并对其进... 详细信息

目的:部分患者的组织病理学表现符合慢性萎缩性胃炎,而相应的内镜检查却没有报告慢性萎缩性胃炎。本研究拟将组织病理学表现符合萎缩和肠化生的患者作为研究的目标人群,探讨这部分人群的临床特征、病理结果与内镜检查的符合率,并对其进行差异性分析。方法:收集2011年1月至2020年12月在湘雅三医院和长沙市中心医院就诊的慢性萎缩性胃炎的胃镜检查和病理诊断的结果。根据病理学检查结果与内镜检查结果将患者分为相符组和不符组,比较2组临床特征、病理学检查与内镜检查的差异。结果:研究纳入病理符合慢性萎缩性胃炎患者2446例,其中男1472例(60.2%),胃窦萎缩者1829例(74.8%),伴有肠化生者1806例(73.8%)。病理学检查与内镜检查的诊断符合率为87.0%。相符组与不相符组在病变部位的分布上有差异(P<0.001)。在年龄<60岁的人群中,不相符组的年龄较相符组更年轻[分别为(47.6±8.8)和(49.9±7.2)岁,P<0.001]。结论:慢性萎缩性胃炎男性较为多见,萎缩部位主要位于胃窦,大多数患者伴有肠化生。病理学检查与内镜检查结果不相符的情况在非胃窦部位和相对年轻的患者中更为常见。

关键词：慢性萎缩性胃炎组织病理学内镜检查萎缩肠化生

A multi-wavelength study of the gravitational lens COSMOS J095930+023427

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Research in Astronomy and Astrophysics 2013年第1期13卷 15-27页

作者： shuo cao Giovanni Covone Maurizio Paolillo Zong-Hong Zhu Department of Astronomy Beijing Normal University Dipartimento di Scienze Fisiche Universita` di Napoli "Federico II" Complesso Universitario di Monte S.Angelo INFN Sezione di NapoliComplesso Universitario di Monte S.Angelo

We present a multi-wavelength study of the gravitational lens COSMOS J095930＋023427 （Zl = 0.892）, together with the associated galaxy group along the line of sight located at z 0.7, and the lensed background galaxy. The source redshift is currently unknown, but estimated to be at zs ~ 2. This analysis is based on publicly available HST, Subaru and Chandra imaging data, as well as VLT spectroscopy. The lensing system is an early-type galaxy showing a strong [OII] emission line, and pro- duces four bright images of the distant background source. It has an Einstein radius of 0.79＂, about four times larger than the effective radius. We perform a lensing anal- ysis using both a singular isothermal ellipsoid and a peudo-isothermal elliptical mass distribution for the lensing galaxy, and find that the final results on the total mass, the dark matter （DM） fraction within the Einstein radius and the external shear due to a foreground galaxy group are robust with respect to the choice of the parametric model and the source redshift （yet unknown）. We measure the luminous mass from the pho- tometric data, and find the DM fraction within the Einstein radius fDM to be between 0.71 ~ 0.13 and 0.79 ~ 0.15, depending on the unknown source redshift. Meanwhile, the non-null external shear found in our lensing models supports the presence and structure of a galaxy group at z ~ 0.7, and an independent measurement of the 0.5- 2 keV X-ray luminosity within 20＂ around the X-ray centroid provides a group mass of M = （3 - 10） x 1013 Mo, in good agreement with the previous estimate derived through weak lensing analysis. Finally, by inverting the HST/ACS/814 image with the lensing equation, we obtain the reconstructed image of the magnified source galaxy, which has a scale of about 3.3 kpc at z~ = 2 （2.7 kpc at zs = 4） and the typical disturbed disk-like appearance observed in low-mass star-forming galaxies at z ~ 3. However, deep, spatially resolved spectroscopic data for similar lensed sour

关键词： galaxies: individual (COSMOS J095930+023427) -- gravitational lens-ing -- dark matter

Multiple measurements of quasars acting as standard probes: Model independent calibration and exploring the dark energy equation of states

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Science China(Physics,Mechanics & Astronomy) 2021年第5期64卷 97-109页

作者： XiaoGang Zheng shuo cao Marek Biesiada XiaoLei Li TongHua Liu YuTing Liu School of Eletrical and Electronic Engineering Wuhan Polytechnic UniversitWuhan 430023China Department of Astronomy Beiing Normnal UniversityBeijing 100875China National Centre for Nuclear Research Warsaw 02-093Poland College of Physics Hebei Normal UniversiryShijiazhuang 050024China

Recently, two classes of quasar samples were identified, which are promising as new cosmological probes extending to higher redshifts. The first sample uses the nonlinear relation between the ultraviolet and X-ray luminosities of quasars to derive luminosity distances, whereas the linear sizes of compact radio quasars in the second sample can serve as standardized rulers, providing angular-diameter distances. In this study, under the assumption of a flat universe, we refreshed the calibration of multiple measurements of high-redshift quasars(in the framework of a cosmological-model-independent method with the newest Hubble parameters data). Furthermore, we placed constraints on four models that characterize the cosmic equation of state(w). The obtained results show that:(1) the two quasar samples could provide promising complementary probes at much higher redshifts,whereas compact radio quasars perform better than ultraviolet and X-ray quasars at the current observational level;(2) strong degeneracy between the cosmic equation of state(w) and Hubble constant(H0) is revealed, which highlights the importance of independent determination of H0 from time-delay measurements of strongly lensed quasars;(3) together with other standard ruler probes, such as baryon acoustic oscillation distance measurements, the combined QSO+BAO measurements are consistent with the standard ΛCDM model at a constant equation of state w =-1;(4) ranking the cosmological models, the polynomial parametrization gives a rather good fit among the four cosmic-equation-of-state models, whereas the Jassal-Bagla-Padmanabhan(JBP) parametrization is substantially penalized by the Akaike Information Criterion and Bayesian Information Criterion.

关键词： dark energy experiments dark energy theory quasars

Double Update Intelligent Strategy for Permanent Magnet Synchronous Motor Parameter Identification

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Computers, Materials & Continua 2023年第2期74卷 3391-3404页

作者： Shuai Zhou Dazhi Wang Mingtian Du Ye Li shuo cao School of Information Science and Engineering Northeastern UniversityShenyang110819China Department of Mechanical Engineering The University of MelbourneVictoria3010Australia College of Information Engineering Shenyang Polytechnic CollegeShenyang110045China

The parameters of permanent magnet synchronous motor(PMSM)affect the performance of vector control servo *** of the complexity of nonlinear model of PMSM,it is very difficult to identify the parameters of *** at the problems of large amount of data calculation,low identification accuracy and poor robustness in the process of multi parameter identification of permanent magnet synchronous motor,this paper proposes a weighted differential evolutionary particle swarm optimization algorithm based on double update *** introducing adaptive judgment factor to control the proportion of weighted difference evolution(WDE)algorithm and particle swarm optimization(PSO)algorithm in each iteration process,and consider using PSO algorithm or WDE algorithm to update individuals according to the probability *** individuals obtained from WDE operation are used to guide the individual evolution process in PSO operation through the information *** proposed WDEPSO algorithm can ensure the diversity and effectiveness of the individual evolution of the *** algorithm is applied to parameter identification of PMSMdrive *** simulation results show that the proposed algorithm has better convergence performance and has strong robustness,parameter identification of permanent magnet synchronous motor based on proposed method does not need to rely on more data sheet on the motor design value,can motor stator resistance identification at the same time,the rotor flux linkage,d/q-axis inductance and electrical parameters,and can effectively track the parameters value.

关键词： PMSM parameter identification WDE PSO WDEPSO

Relativistic motion on Gaussian quantum steering for two-mode localized Gaussian states

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Chinese Physics B 2022年第5期31卷 189-196页

作者： Xiao-Long Gong shuo cao Yue Fang Tong-Hua Liu School of Physics and Optoelectronic Yangtze UniversityJingzhou 434023China Department of Astronomy Beijing Normal UniversityBeijing 100875China Advanced Institute of Natural Sciences Beijing Normal University at ZhuhaiZhuhai 519087China

Realistic quantum systems always exhibit gravitational and relativistic *** this paper,we investigate the properties of Gaussian steering and its asymmetry by the localized two-mode Gaussian quantum states,instead of the traditional single-mode approximation method in the relativistic *** find that the one-side Gaussian quantum steering will monotonically decrease with increasing observers of ***,our results also reveal the interesting behavior of the Gaussian steering asymmetry,which increases for a specific range of accelerated parameter and then gradually approaches to a finite *** finding is well consistent and explained by the well-known Unruh effect,which could significantly destroy the one-side Gaussian quantum ***,our results could also be applied to the dynamical studies of Gaussian steering between the Earth and satellites,since the effects of acceleration are equal to the effects of gravity according to the equivalence principle.

关键词： relativistic quantum information quantum nonlocality Unruh effect

开展可见光—红外线—太赫兹波成像系列实验培养解决真实问题人才

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物理与工程 2024年第2期34卷 110-114页

作者：曹硕孔令茹杜增李永庆辽宁大学物理学院辽宁沈阳110036

物理学的研究成果有力推动了三次工业革命的发展。进入新世纪以来,量子计算、低维物理、量子探测等现代物理研究成果正在促进第四次工业革命暨工业4.0向纵深发展。笔者在大学物理实验中规划布局多层次物理实验题目,以开展可见光-红外线... 详细信息

物理学的研究成果有力推动了三次工业革命的发展。进入新世纪以来,量子计算、低维物理、量子探测等现代物理研究成果正在促进第四次工业革命暨工业4.0向纵深发展。笔者在大学物理实验中规划布局多层次物理实验题目,以开展可见光-红外线-太赫兹波探测与成像系列实验为例,介绍了学生深刻理解不同波段的电磁波在新旧产业领域应用性的异同。这一教学模式有利于学生掌握近现代物理成果与实验综合技能,培养他们成为解决新产业领域面临的真实问题的新理工科人才,从容面对新技术革命与职业选择。

关键词：多层次物理实验三次工业革命工业4.0 可见光—红外线—太赫兹波成像

Three-Dimensional Analytical Modeling of Axial-Flux Permanent Magnet Drivers

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Computers, Materials & Continua 2023年第4期75卷 259-276页

作者： Wenhui Li Dazhi Wang shuo cao Deshan Kong Sihan Wang Zhong Hua Northeastern University Shenyang110819China Shenyang Polytechnic College Shenyang110819China

In this paper, the axial-flux permanent magnet driver is modeledand analyzed in a simple and novel way under three-dimensional cylindricalcoordinates. The inherent three-dimensional characteristics of the deviceare comprehensively considered, and the governing equations are solved bysimplifying the boundary conditions. The axial magnetization of the sectorshapedpermanent magnets is accurately described in an algebraic form bythe parameters, which makes the physical meaning more explicit than thepurely mathematical expression in general series forms. The parameters of theBessel function are determined simply and the magnetic field distribution ofpermanent magnets and the air-gap is solved. Furthermore, the field solutionsare completely analytical, which provides convenience and satisfactoryaccuracy for modeling a series of electromagnetic performance parameters,such as the axial electromagnetic force density, axial electromagnetic force,and electromagnetic torque. The correctness and accuracy of the analyticalmodels are fully verified by three-dimensional finite element simulations and a15 kW prototype and the results of calculations, simulations, and experimentsunder three methods are highly consistent. The influence of several designparameters on magnetic field distribution and performance is studied and *** results indicate that the modeling method proposed in this papercan calculate the magnetic field distribution and performance accurately andrapidly, which affords an important reference for the design and optimizationof axial-flux permanent magnet drivers.

关键词： Three-dimensional analytical modeling cylindrical coordinates magnetic field distribution parameter sensitivity analysis performance measurement

Comparison of cosmological models using standard rulers and candles

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Research in Astronomy and Astrophysics 2016年第5期16卷 125-134页

作者： Xiao-Lei Li shuo cao Xiao-Gang Zheng Song Li Marek Biesiada Department of Astronomy Beiiing Normal UniversityBeijing 100875China Department of Physics Capital Normal UniversityBeijing 100048China Department of Astrophysics and Cosmology Institute of PhysicsUniversity of SilesiaUniwersytecka 440-007KatowicePoland

In this paper, we used standard rulers and standard candles （separately and jointly） to explore five popular dark energy models under the assumption of the spatial flatness of the Universe. As standard rulers, we used a data set comprised of 118 galactic scale strong lensing systems （individual standard rulers if properly calibrated for the mass density profile） combined with BAO diagnostics （statistical standard ruler）. Type Ia supernovae served as standard candles. Unlike most previous statistical studies involving strong lensing systems, we relaxed the assumption of a singular isothermal sphere （SIS） in favor of its generalization： the power-law mass density profile. Therefore, along with cosmological model parameters, we fitted the power law index and its first derivative with respect to the redshift （thus allowing for mass density profile evolution）. It turned out that the best fitted ~/parameters are in agreement with each other, irrespective of the cosmological model considered. This demonstrates that galactic strong lensing systems may provide a complementary probe to test the properties of dark energy. The fits for cosmological model parameters which we obtained are in agreement with alternative studies performed by other researchers. Because standard rulers and standard candles have different parameter degeneracies, a combination of stan- dard rulers and standard candles gives much more restrictive results for cosmological parameters. Finally, we attempted an analysis based on model selection using information theoretic criteria （AIC and BIC）. Our results support the claim that the cosmological constant model is still best and there is no （at least statistical） reason to prefer any other more complex model.

关键词： (cosmology:) dark energy -- cosmology: observations -- (cosmology:) cosmological param-eters