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Frontiers of Structural and Civil Engineering 2024年第1期18卷 14-29页

作者： Jing xu Xianzhi WANG Wu YAO Anna A.KULMINSKAYA Surendra p.SHAH Key Laboratory of Advanced Civil Engineering Materials(Ministry of Education) School of Materials Science and EngineeringTongji UniversityShanghai 201804China petersburg Nuclear physics institute Named by B.p.Konstantinov of National Research Centre Kurchatov InstituteGatchina 188300Russia Center for Advanced Construction Materials University of Texas at ArlingtonArlingtonTX 76019USA

Microbially induced carbonate precipitation(MICp)is a promising technique for the autonomous healing of concrete *** this study,the effect of pH on MICp was *** results indicate that the MICp process was inhibited when the pH was higher than *** vaterite and calcite were produced when the pH wasproduced when the pH was>*** concrete aggregates(RCA)coated with sodium silicate have been proposed as protective carriers for microbial healing *** the presence of the coated RCA resulted in a loss of the splitting tension strength of the concrete,the loaded healing agents were highly efficient in self-healing *** incorporated with 20%RCA loaded with healing agents exhibited the best self-healing *** the initial crack widths were between 0.3 and 0.4 mm,the 7-d mean healing rate was approximately 90%.At 28 d,the crack area filling ratio was 86.4%,while its water tightness recovery ratio was 74.4%and 29.8%,respectively,for rapid and slow *** study suggests that RCA coated with sodium silicate is an effective method for packaging microbial healing agents and has great potential for developing cost-effective self-healing concrete.

关键词： self-healing microbial-induced carbonate precipitation water uptake recycled concrete aggregate protective carrier

Quantifying the strength of magnetic fields using baryon electric charge correlation

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Nuclear Science and Techniques 2024年第8期35卷 5-8页

作者： xu‑Guang Huang physics Department and Center for particle physics and Field Theory Fudan UniversityShanghai 200433China Key Laboratory of Nuclear physics and Ion‑beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear physics National Natural Science Foundation of China and Fudan UniversityShanghai 200438China

Although heavy-ion collisions generate strong magnetic fields,their direct measurement is a challenging task.A new observable,the baryon electric charge correlation,was recently found to be sensitive to the magnetic field strength and thus could be used as a magnetometer for heavy-ion ***,this observable may shed light on the equation of state and phase structure of quantum chromodynamics(QCD)under magnetic *** and understanding the phase structure of quantum chromodynamics(QCD)is important in contemporary physics[1].

关键词： charge observable magnetic

ON THE BINDING ENERGIES OF THE NUCLEI ~6Li AND ~7Li pART Ⅰ.GENERAL FORMULATION(Contributions from institute of modern physics,Academia Sinica,No.3)

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中国物理学报 1950年第2期 445-453页

作者： KING SING-NANinstitute of modern physics, Academia Sinica

By using the nuclear potential obtained by peng and Chang as a working hypotnesis,we haveobtained the general formulae for computing the binding energies of ~6Li and ~7Li,the wave functionsbeing approximated by those ... 详细信息

关键词： Li ON THE BINDING ENERGIES OF THE NUCLEI pART AND Contributions from institute of modern physics,Academia Sinica,No.3 GENERAL FORMULATION

Nonlinear Extrapolation Estimates of π

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 91-108页

作者： Wen-qing xu Sha-sha Wang Da-chuan xu Beijing institute for Scientific and Engineering Computing Beijing University of TechnologyBeijing100124China Department of Mathematics and Statistics California State UniversityLong BeachCalifornia90840USA Department of Mathematics and physics Shijiazhuang Tiedao UniversityShijiazhuang050043China

The classical Archimedean approximation of π uses the semiperimeter or area of regular polygons inscribed in or circumscribed about a unit circle in R~2 and it is well-known that by using linear combinations of these basic estimates,modern extrapolation techniques can greatly speed up the approximation ***,when n vertices are randomly selected on the circle,the semiperimeter and area of the corresponding random inscribed and circumscribing polygons are known to converge to π almost surely as n→∞,and by further applying extrapolation processes,faster convergence rates can also be achieved through similar linear combinations of the semiperimeter and area of these random *** this paper,we further develop nonlinear extrapolation methods for approximating π through certain nonlinear functions of the semiperimeter and area of such *** focus on two types of extrapolation estimates of the forms χ_n=S_n~αA_n~β and Y_n(p)=(αS_n~p+βA_n~p)~(1/p) where α+β=1,p≠0,and Sn and An respectively represents the semiperimeter and area of a random n-gon inscribed in the unit circle in R~2,and Xn may be viewed as the limit of Y_n(p) when p→*** deriving probabilistic asymptotic expansions with carefully controlled error estimates for Xn and Y_n(p),we show that the choice α=4/3,β=-1/3 minimizes the approximation error in both cases,and their distributions are also asymptotically normal.

关键词： Archimedean polygons random polygons approximations ofπ extrapolation processes asymptotic convergence

ON THE BINDING ENERGIES OF THE NUCLEI ~6Li AND ~7Li pART Ⅱ NUMERICAL CALCULATION FOR ~6Li(Contributions from institute of modern physics, Academia Sinica,No.4)

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中国物理学报 1950年第2期 462-474页

作者： YEH LUNG-FEYinstitute of modern physics, Academia Sinica

By using the formulae obtained in part Ⅰ for the calculation of the binding energy of ~6Li,anumerical estimate is made here-the variational function being chosen rather *** resultsare in favour of the two-range nuclear potential considered previously,and indeed indicate a largerratio of the two ranges,the ratio being not smaller than three.

关键词： Li AND Academia Sinica,No.4 NUMERICAL CALCULATION FOR ON THE BINDING ENERGIES OF THE NUCLEI pART

Transverse mode-coupling instability with longitudinal impedance

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Nuclear Science and Techniques 2024年第6期35卷 40-53页

作者： Hai-Sheng xu Chun-Tao Lin Na Wang Jing-Ye xu Yuan Zhang Key Laboratory of particle Acceleration physics and Technology Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China institute of Advanced Science Facilities Shenzhen 518107GuangdongChina

Transverse mode-coupling instability(TMCI)is a dangerous transverse single-bunch instability that can lead to severe par-ticle *** mechanism of TMCI can be explained by the coupling of transverse coherent oscillation modes owing to the transverse short-range wakefield(i.e.,the transverse broadband impedance).Recent studies on future circular colliders,e.g.,FCC-ee,showed that the threshold of TMCI decreased significantly when both longitudinal and transverse impedances were *** performed computations for the circular electron-positron collider(CEpC)and observed a similar *** studies on the influence of longitudinal impedance on the TMCI threshold were *** concluded that the imaginary part of the longitudinal impedance,which caused a reduction in the incoherent synchrotron tune,was the primary reason for the reduction in the TMCI ***,the real part of the longitudinal impedance assists in increasing the TMCI threshold.

关键词： Transverse mode-coupling instability Longitudinal impedance

Frequency-domain analysis of fluid-structure interaction in aircraft hydraulic pipeline systems: numerical and experimental studies

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Journal of Zhejiang University-Science A(Applied physics & Engineering) 2024年第8期25卷 605-617页

作者： Yang DENG Zongxia JIAO Yuanzhi xu School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China Research institute for Frontier Science Beihang UniversityBeijing 100191China Key Laboratory of Advanced Airborne Systems Beihang UniversityBeijing 100191China Ningbo institute of Technology Beihang UniversityNingbo 315800China Tianmushan Laboratory Hangzhou 310023China

The fluid-structure interaction(FSI)in aircraft hydraulic pipeline systems is of great concern because of the damage it *** accurately predict the vibration characteristic of long hydraulic pipelines with curved segments,we studied the frequency-domain modeling and solution method for FSI in these pipeline *** partial differential equations(pDEs)are utilized to model the pipeline FSI,considering both frequency-dependent friction and bending-flexibility *** address the numerical instability encountered by the traditional transfer matrix method(TMM)in solving relatively complex pipelines,an improved TMM is proposed for solving the pDEs in the frequency domain,based on the matrix-stacking strategy and matrix representation of boundary *** proposed FSI model and improved solution method are validated by numerical cases and *** experimental rig of a practical hydraulic system,consisting of an aircraft engine-driven pump,a Z-shaped aero-hydraulic pipeline,and a throttle valve,was constructed for *** magnitude ratio of acceleration to pressure is introduced to evaluate the theoretical and experimental results,which indicate that the proposed model and solution method are effective in practical *** methodology presented in this paper can be used as an efficient approach for the vibrational design of aircraft hydraulic pipeline systems.

关键词： Fluid-structure interaction(FSI) Frequency-domain analysis Aircraft hydraulic pipeline pipeline vibration Transfer matrix method(TMM)

Discovery of partial Differential Equations from Highly Noisy and Sparse Data with physics-Informed Information Criterion

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Research 2024年第1期2023卷 247-259页

作者： Hao xu Junsheng Zeng Dongxiao Zhang BIC-ESAT EREand SKLTCSCollege of EngineeringPeking UniversityBeijing 100871P.R.China institute of Applied physics and Computational Mathematics Beijing 100088P.R.China Eastern institute for Advanced Study Eastern Institute of TechnologyNingbo 315200ZhejiangP.R.China National Center for Applied Mathematics Shenzhen(NCAMS) Southern University of Science and TechnologyShenzhen 518055GuangdongP.R.China Department of Mathematics and Theories Peng Cheng LaboratoryShenzhen 518000GuangdongP.R.China

Data-driven discovery of partial differential equations(pDEs)has recently made tremendous progress,and many canonical pDEs have been discovered successfully for proof of ***,determining the most proper pDE without prior references remains challenging in terms of practical *** this work,a physics-informed information criterion(pIC)is proposed to measure the parsimony and precision of the discovered pDE *** proposed pIC achieves satisfactory robustness to highly noisy and sparse data on 7 canonical pDEs from different physical scenes,which confirms its ability to handle difficult *** pIC is also employed to discover unrevealed macroscale governing equations from microscopic simulation data in an actual physical *** results show that the discovered macroscale pDE is precise and parsimonious and satisfies underlying symmetries,which facilitates understanding and simulation of the physical *** proposition of the pIC enables practical applications of pDE discovery in discovering unrevealed governing equations in broader physical scenes.

关键词： process canonical proof

A high power MOpA free-electron laser with narrowline-width

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Nuclear Science and Techniques 1999年第3期10卷 165-167页

作者： SHU Xiaojian (institute of modern physics, Fudan University, Shanghai 200433 institute of Applied physics and Computational Mathematics, Beijing 100088) 复旦大学物理系上海

A new kind of MOpA configuration to obtain a high power free-electron laser with very narrow line-width that can satisfy the requirements of some applications such as the laser isotope separation has been proposed, wh... 详细信息

关键词：自由电子激光器线宽窄功率大