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Improved Reliability Analysis Method Based on the Failure Assessment Diagram

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Chinese Journal of Mechanical Engineering 2012年第4期25卷 832-837页

作者： ZHOU yu ZHANG Zheng zhong Qunpeng School of Material Science and Engineering Beihang University Beijing 100191 China

With the uncertainties related to operating conditions,in-service non-destructive testing（NDT） measurements and material properties considered in the structural integrity assessment,probabilistic analysis based on the failure assessment diagram（FAD） approach has recently become an important ***,the point density revealing the probabilistic distribution characteristics of the assessment points is usually *** obtain more detailed and direct knowledge from the reliability analysis,an improved probabilistic fracture mechanics（PFM） assessment method is *** integrating 2D kernel density estimation（KDE） technology into the traditional probabilistic assessment,the probabilistic density of the randomly distributed assessment points is visualized in the assessment ***,a modified interval sensitivity analysis is implemented and compared with probabilistic sensitivity *** improved reliability analysis method is applied to the assessment of a high pressure pipe containing an axial internal semi-elliptical surface *** results indicate that these two methods can give consistent sensitivities of input parameters,but the interval sensitivity analysis is computationally more ***,the point density distribution and its contour are plotted in the FAD,thereby better revealing the characteristics of PFM *** study provides a powerful tool for the reliability analysis of critical structures.

关键词： reliability analysis failure assessment diagram probabilistic fracture mechanics kernel density estimation sensitivity analysis

Petroleum systems in the Damintun Depression, Liaohe Oilfield

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1864-1871页

作者： ZHENG Li-hui XING yu-zhong School of Energy Resources China University of Geosciences Beijing 100083 China International Research Center Beijing China National Petroleum Corporation （CNPC） Beijing 100083 China

There are two different types of oils—high-wax oil and normal oil—found in the Damintun Depression of Liaohe Oilfield after several years of exploration and development, but their distributions and origins had confused the explorers in the oilfield. The introduction of petroleum-system concept shifts the view of geoscientists from geology and geophysics to oil, gas and their related source rocks. After detailed study, two petroleum systems have been identified in the Damintun Depression: (1) the ES42-Ar buried hill petroleum system (called the high-wax oil petroleum system) and (2) the ES41+ES34-ES4 and ES3 petroleum system (called the normal oil petroleum system). Based on the detailed analysis of the basic components, and all the geological processes required to create these elements of the two petroleum systems, it is put forward that targets for future exploration should include the area near Dongshenpu-Xinglongpu and the area near the Anfutun Sag. This provides scientific basis and has theoretical and practical meaning for the exploration and development.

关键词： Petroleum system Source rock Geochemical characteristics Hydrocarbon migration

Interior non-uniformity of acoustically excited oscillating gas bubbles

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Journal of Hydrodynamics 2019年第4期31卷 725-732页

作者： yu-ning Zhang Xiao-fei Li zhong-yu Guo Key Laboratory of Condition Monitoring and Control for Power Plant Equipment (Ministry of Education) School of Energy Power and Mechanical Engineering North China Electric Power University Beijing 102206 China Key Labor at oiy of Fluid and Power Machinery Ministry of Education Xihua IJnivarsily Chengdu 610039 China College of Mechanical and Transportation Engineering China University of Petroleum-Beijing Beijing 102249 China Beijing Key Laboratory of Process Fluid Filtration and Separation China University of Petroleum-Beijing Beijing 102249 China

In the present paper, the interior non-uniformity of oscillating gas bubbles in liquids under an acoustic field is theoretically investigated, as well as the temperature non-uniformity in the surrounding liquid. The pressure, the density and the temperature inside the gas bubbles are quantitatively predicted for a wide range of bubble Mach numbers. It is shown that the bubble interior non-uniformity increases significantly with the increase of the bubble Mach number. In the case of a large Mach number, the values of aforementioned paramount parameters at the bubble center are significantly larger than those at the bubble interface. Except for a very thin layer close to the bubble interface, the effects of the temperature non-uniformity in the bulk liquid could be safely ignored.

关键词： Cavitation gas bubbles acoustic field radial oscillation non-uniformity Mach number

WORMHOLE AND THE DIMENSIONALITY OF SPACETIME IN EINSTEIN-GAUGE THEORIES

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Chinese Physics Letters 1990年第6期7卷 248-251页

作者： LI Xinzhou zhong yu East China Institute for Theoretical Physics Shanghai 200237 East China University of Chemical Technology Shanghai200237

The wormhole effect is discussed in the d-dimensional Einstein-Yang-Mills *** show that the peak of the probability function leads to the explanation of the spontaneous compactification down to a four-dimensional spacetime and vanishing four-dimensional cosmological constant,i.e.,the observable spacetime must be four-dimensional and flat.

关键词： theory SPACE dimensional

Synthesis and Crystal Structure of the Complex [Zn(DBSHSH)(py)_2]

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1347-1350页

作者： DING yu ZHANG zhong-Hai yu Guo-Feng Department of Chemistry Xiaogan University Xiaogan Hubei 432000 China

The title complex, C24H18Br2N4ZnO3, has been prepared and characterized by X- ray diffraction analysis. It crystallizes in the triclinic system, space group PI^- with α = 0.89000（11）, b = 1.22172（14）, c= 1.31342（16）nm, a = 101.696（2）, β = 103.519（2）, γ = 110.744（2）°, V= 1.2329（3） nm^3, Z = 2, Mr = 635.61, F（000） = 628, Dc= 1.712 g/cm^3 and μ（MoKa） = 4.270 mm^-1. The structure was refined to the final R = 0.0524 and wR = 0.1239 for 2763 observed reflections with I 〉 2σ（ I）. The X-ray crystal structure analysis revealed that the center zinc（Ⅱ） is bonded with two oxygen and one nitrogen atoms from a tridentate ligand 3,5-dibromo-salicylaldehyde salicyloylhydrazone （DBSHSH） and two nitrogen atoms from two solvent pyridine molecules to form a distorted five-coordinate trigonal bipyramid. The intramolecular hydrogen bonds in the crystal structure play an important role in the title complex＇s thermostability.

关键词： 3,5-dibromo-salicylaldehyde salicyloylhydrazone [Zn(DBSHSH)(py)2] crystal structure

Towards precise synthesis of functional polymers by iterative electropolymerization

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Science China Chemistry 2020年第9期63卷 1175-1176页

作者： Kun Tang yu-Wu zhong Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of PhotochemistryCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

The controllable synthesis of polymers and macromolecules with precise structures is one of the biggest challenges in polymer chemistry[1].Although polymers with welldefined architectures and compositions could now be prepared by various living polymerization techniques[1],it remains elusive to produce macromolecular materials with precise controls of monomer sequences and easy purification procedures.

关键词： precise polymerization synthesis

Influence of Mass-Loss on the Orbit of Comet Shoemaker-Levy 9

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Chinese Physics Letters 1996年第6期13卷 477-480页

作者： yu Li-zhong ZHENG Xue-tang Department of Applied Physics Nanjing University of Science and TechnologyNanjing 210094

Using the Jeans problem and the Fermi problem of two bodies with variable masses,the influence of solar and cometary mass-loss on the orbit of comet Shoemaker-Levy 9(SL9)is discussed in this *** is shown that solar and cometary mass-loss both will cause the secular and periodic terms in the semimajor axis a of comet *** influence of solar mass-loss on the orbit of comet SL9 is very small and it may be *** the influence of mass-loss of comet SL9 itself on its orbit is large and it may cause the secular variation in a to be about l04 km every *** cometary mass-loss will obviously influence the time and place of the comet SL9 crashing into Jupiter.

关键词： comet Jupiter mass

Analytical and numerical study of chirped optical solitons in a spatially inhomogeneous polynomial law fiber with parity-time symmetry potential

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Communications in Theoretical Physics 2023年第2期75卷 28-38页

作者： yu zhong Houria Triki Qin Zhou Research Group of Nonlinear Optical Science and Technology School of Mathematical and Physical SciencesWuhan Textile UniversityWuhan 430200China Radiation Physics Laboratory Department of PhysicsFaculty of SciencesBadji Mokhtar UniversityP.O.Box 1223000 AnnabaAlgeria State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200China

This work studies the dynamical transmission of chirped optical solitons in a spatially inhomogeneous nonlinear fiber with cubic-quintic-septic nonlinearity,weak nonlocal nonlinearity,self-frequency shift and parity-time(PT)symmetry potential.A generalized variable-coefficient nonlinear Schr?dinger equation that models the dynamical evolution of solitons has been investigated by the analytical method of similarity transformation and the numerical mixed method of split-step Fourier method and Runge–Kutta *** analytical self-similar bright and kink solitons,as well as their associated frequency chirps,are derived for the first *** found that the amplitude of the bright and kink solitons can be controlled by adjusting the imaginary part of the PT-symmetric ***,the influence of the initial chirp parameter on the soliton pulse widths is quantitatively *** is worth emphasizing that we could control the chirp whether it is linear or nonlinear by adjusting optical fiber *** simulation results of bright and kink solitons fit perfectly with the analytical ones,and the stabilities of these soliton solutions against noises are checked by numerical simulation.

关键词： solitons symmetry inhomogeneous

Accumulated damage process of thermal sprayed coating under rolling contact by acoustic emission technique

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Frontiers of Mechanical Engineering 2016年第3期11卷 227-232页

作者： Jia XU Zhen-yu ZHOU zhong-yu PIAO Key Laboratory of Special Purpose Equipment and Advanced Processing Technology (Zhejiang University of Technology) Ministry ofEducation and Zhejiang Province Hangzhou 310014 China Key Laboratory of Special Purpose Equipment and Advanced Processing Technology (Zhejiang University of Technology) Ministry ofEducation and Zhejiang Province Hangzhou 310014 China The StateKey Laboratory of Fluid Power Transmission and Control Hangzhou310027 China

The accumulated damage process of rolling contact fatigue （RCF） of plasma-sprayed coatings was investigated. The influences of surface roughness, loading condition, and stress cycle frequency on the accumulated damage status of the coatings were discussed. A ball-on- disc machine was employed to conduct RCF experiments. Acoustic emission （AE） technique was introduced to monitor thc RCF process of the coatings. AE signal characteristics were investigated to reveal the accumulated damage process. Result showed that the polished coating would resist the asperity contact and remit accumulated damage. The RCF lifetime would then extend. Heavy load would aggravate the accumulated damage status and induce surface fracture. Wear became the main failure mode that reduced the RCF lifetime. Frequent stress cycle would aggravate the accumulated damage status and induce interface fracture. Fatigue then became the main failure mode that also reduced the RCF lifetime.

关键词： accumulated damage spray coating rolling contact fatigue acoustic emission