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Linearity relationship between solvatochromic shifts of stilbazolium-like dyes and modified reaction field function
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作者 詹传郎 王夺元 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2000年第3期418-424,共7页
We analyzed statistically the linear correlation of the solvatochromic shifts of the stilbazolium-like dyes in the nonselected solvents with the reaction field function, L(?T) — bL(n2), and the solvent polarity param... We analyzed statistically the linear correlation of the solvatochromic shifts of the stilbazolium-like dyes in the nonselected solvents with the reaction field function, L(?T) — bL(n2), and the solvent polarity parameter, ENT respectively, and observed that there were not perfectly linearity relationships between them, so we introduced ENT into L(?T) — bL( n2) to form a new reaction field function, L(?T) — bL(n2) + g ENT called as me modified reaction field function, which can be perfectly linearly correlated with the solvatochromic shifts of the stilbazolium-like dyes in the nonselected solvents. 展开更多
关键词 Stilbazolium-like dye solvatochromic shift modified reaction field function
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Molecular properties and potential energy function model of BH under external electric field 被引量:7
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作者 伍冬兰 谭彬 +2 位作者 万慧军 张新琴 谢安东 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期194-198,共5页
Using the density functional B3P86/cc-PV5Z method, the geometric structure of BH molecule under different external electric fields is optimized, and the bond lengths, dipole moments, vibration frequencies, and other p... Using the density functional B3P86/cc-PV5Z method, the geometric structure of BH molecule under different external electric fields is optimized, and the bond lengths, dipole moments, vibration frequencies, and other physical properties parameters are obtained. On the basis of setting appropriate parameters, scanning single point energies are obtained by the same method and the potential energy curves under different external fields are also obtained. These results show that the physical property parameters and potential energy curves may change with external electric field, especially in the case of reverse direction electric field. The potential energy function without external electric field is fitted by Morse potential, and the fitting parameters are obtained which are in good agreement with experimental values. In order to obtain the critical dissociation electric parameter, the dipole approximation is adopted to construct a potential model fitting the corresponding potential energy curve of the external electric field. It is found that the fitted critical dissociation electric parameter is consistent with numerical calculation, so that the constructed model is reliable and accurate. These results will provide important theoretical and experimental reference for further studying the molecular spectrum, dynamics, and molecular cooling with Stark effect. 展开更多
关键词 BH molecule potential function model external electric field
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Nonlinear Transient Response of Functionally Graded Material Sandwich Doubly Curved Shallow Shell Using New Displacement Field 被引量:2
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作者 Z.N.Li Y.X.Hao +1 位作者 W.Zhang J.H.Zhang 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2018年第1期108-126,共19页
In this paper, the nonlinear transient dynamic response of functionally graded material (FGM) sandwich doubly curved shell with homogenous isotropic material core and functionally graded face sheet is analyzed using... In this paper, the nonlinear transient dynamic response of functionally graded material (FGM) sandwich doubly curved shell with homogenous isotropic material core and functionally graded face sheet is analyzed using a new displacement field on the basis of Reddy's third-order shear theory for the first time. The equivalent material properties for the FGM face sheet are assumed to obey the rule of simple power law function in the thickness direction. Based on Reddy's theory of higher shear deformation, a new displacement field is developed by introducing the secant function into transverse displacement. Four coupled nonlinear differential equations are obtained by applying Hamilton's principle and Galerkin method. It is assumed that the FGM sandwich doubly curved shell is subjected to step loading, air-blast loading, triangular loading, and sinusoidal loading, respectively. On the basis of double-precision variable- coefficient ordinary differential equation solver, a new program code in FORTRAN software is developed to solve the nonlinear transient dynamics of the system. The influences of core thickness, volume fraction, core-to-face sheet thickness ratio, width-to-thickness ratio and blast type on the transient response of the shell are discussed in detail through numerical simulation. 展开更多
关键词 New displacement fields functionally graded materials Sandwich doubly curvedshell Blast load Nonlinear transient response
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Numerical modeling calculation for the spatial distribution characteristics of horizontal field transfer functions
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作者 龚绍京 陈化然 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2001年第6期676-684,共9页
Applying 3-dimension finite difference method, the distribution characteristics of horizontal field transfer functions for rectangular conductor have been computed, and the law of distribution for Re-part and Im-part ... Applying 3-dimension finite difference method, the distribution characteristics of horizontal field transfer functions for rectangular conductor have been computed, and the law of distribution for Re-part and Im-part has been given. The influences of source field period, the conductivity, the buried depth and the length of the conductor on the transfer functions were studied. The extrema of transfer functions appear at the center, the four corners and around the edges of conductor, and move with the edges. This feature demonstrates that around the edges are best places for transfer functions' observation. 展开更多
关键词 numerical modeling 3-D finite difference method horizontal field transfer function spatial distribution characteristics
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The Analytical Potential Energy Function of NH Radical Molecule in External Electric Field 被引量:5
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作者 伍冬兰 谭彬 +2 位作者 万慧军 谢安东 丁大军 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期34-37,共4页
The geometric structures of an Nit radical in different external electric fields are optimized by using the density functional B3P86/cc-PVSZ method, and the bond lengths, dipole moments, vibration frequencies and IR s... The geometric structures of an Nit radical in different external electric fields are optimized by using the density functional B3P86/cc-PVSZ method, and the bond lengths, dipole moments, vibration frequencies and IR spectrum are obtained. The potential energy curves are gained by the CCSD (T) method with the same basis set. These results indicate that the physical property parameters and potential energy curves may change with the external electric field, especially in the reverse direction electric field. The potential energy function of zero field is fitted by the Morse potential, and the fitting parameters are in good accordance with the experimental data. The potential energy functions of different external electric fields are fitted adopting the constructed potential model. The fitted critical dissociation electric parameters are shown to be consistent with the numerical calculation, and the relative errors are only 0.27% and 6.61%, hence the constructed model is reliable and accurate. The present results provide an important reference for further study of the molecular spectrum, dynamics and molecular cooling with Stark effect. 展开更多
关键词 The Analytical Potential Energy function of NH Radical Molecule in External Electric field NH
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A FUNCTION MINIMIZATION CALCULATION OF CYCLONE 10 MAGNETIC FIELDS
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作者 S.Zaremba 王良明 《Nuclear Science and Techniques》 SCIE CAS CSCD 1991年第3期129-134,共6页
By app(?)ing function minimization calculation method, two function expressions are used to simulate the magnetic field measured for cyclotron Cyclone 10 in azimuth and radius The numerical fitting curves are consiste... By app(?)ing function minimization calculation method, two function expressions are used to simulate the magnetic field measured for cyclotron Cyclone 10 in azimuth and radius The numerical fitting curves are consistent with magnetic field measured. In most pl(?)es, the accuracies are several thousandth, except those errors to be pointed out in paper. 展开更多
关键词 function MINIMIZATION CALCULATION MINUIT program Periodic function SEEKING REMAINDER function Fringing field function simulation
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Stress Field Analyses of Functionally Gradient Ceramic Tool by FEM
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作者 Ning FAN , Xing AI and Jun ZHAO Department of Mechanical Engineering, Shandong University,Jinan 250061, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第4期466-468,共3页
The cutting properties of the functionally gradient ceramic cutting tools relate closely to the gradient distribution. A cutting model of the functionally gradient ceramic tool is firstly designed in the present paper... The cutting properties of the functionally gradient ceramic cutting tools relate closely to the gradient distribution. A cutting model of the functionally gradient ceramic tool is firstly designed in the present paper. The optimum of gradient distribution is obtained by way of the FEM analyses. 展开更多
关键词 Stress field Analyses of functionally Gradient Ceramic Tool by FEM TOOL
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A NEW METHOD FOR SOLVING DYADIC GREEN'S FUNCTION OF ELECTROMAGNETIC FIELD
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作者 宋文淼 《Journal of Electronics(China)》 1990年第2期122-134,共13页
A new method for solving electromagnetic field boundary value problem is given.Byusing this method,the boundary value problem of the vector wave equation can be transformedinto the independent boundary value problem o... A new method for solving electromagnetic field boundary value problem is given.Byusing this method,the boundary value problem of the vector wave equation can be transformedinto the independent boundary value problem of scalar wave equations and the two additionalvector differential operations.All the dyadic Green’s functions got by eigenfunction expansionof the dyadic Green’s function can be got by this method easily and some of the dyadic Green’sfunctions for complex systems which are very difficult to get by the ordinary method have beengot by this new method.The dyadic Green’s function for a dielectric loaded cavity is one of thegiven examples. 展开更多
关键词 DYADIC Green’s function ROTATIONAL field Irrotational field VECTOR wave function
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Construction Theory of Function on Local Fields 被引量:1
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作者 Weiyi Su 《Analysis in Theory and Applications》 CSCD 2015年第1期25-44,共20页
We establish the construction theory of function based upon a local field Kp as underlying space. By virture of the concept of pseudo-differential operator, we introduce "fractal calculus" (or, p-type calculus, or,... We establish the construction theory of function based upon a local field Kp as underlying space. By virture of the concept of pseudo-differential operator, we introduce "fractal calculus" (or, p-type calculus, or, Gibbs-Butzer calculus). Then, show the Jackson direct approximation theorems, Bermstein inverse approximation theorems and the equivalent approximation theorems for compact group D(C Kp) and locally compact group Kp^+-(= Kp), so that the foundation of construction theory of function on local fields is established. Moreover, the Jackson type, Bernstein type, and equivalent approximation theorems on the HOlder-type space C^σ(Kp), σ 〉0, are proved; then the equivalent approximation theorem on Sobolev-type space Wr(Kp), σ≥0, 1≤r 〈∞, is shown. 展开更多
关键词 Construction theory of function local field fractal calculus approximation theorem HOlder-type space.
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Proteins as functional interlayer in organic field-effect transistor 被引量:1
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作者 Wei-Hong Zhang Bo-Jing Jiang Peng Yang 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第8期1339-1344,1469,共6页
The paper summarizes and discusses the recent advances of proteins as functional interlayers in organic field-effect transistors(OFETs).Specific focus is given on the proteins integrated into the device structure,ei... The paper summarizes and discusses the recent advances of proteins as functional interlayers in organic field-effect transistors(OFETs).Specific focus is given on the proteins integrated into the device structure,either to act as dielectric materials or to perform as the functional interlayer between the dielectric and the organic semiconductor(OSC).The main emphasis is give to the location and the specific effect of protein layers in the structure of OFETs.Besides,the possibility of amyloid serving as useful building blocks for OFET is discussed. 展开更多
关键词 PROTEIN functional interlayer Organic field-effect transistors Dielectric materials Organic semiconductor
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The anomalous reactions of the geomagnetic horizontal field transfer functions before Tangshan earthquake
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作者 龚绍京 陈化然 +2 位作者 张翠芬 杨程君 马淑芹 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第1期60-69,共10页
We have collected the data of variometers in period from 1972 through 1984 at Changli and Baijiatuan stations. The results calculated from 19 groups of data show: 1) There are no significant anomalies of A... We have collected the data of variometers in period from 1972 through 1984 at Changli and Baijiatuan stations. The results calculated from 19 groups of data show: 1) There are no significant anomalies of A, B at Baijiatuan and that of B at Changli, but there are evident anomalous changes for A u, A v at Changli station. This result basically agrees to the a, b calculated using the method of measuring magnetograms, which demonstrates that the anomalies limited in the aftershock area and its neighbouring regions. 2) There are some changes of the inter station transfer functions of C u, C v, F u, F v before Tangshan earthquake, and the changes of the image parts C v, F v are more obvious, which is in agreement with the research results for Hualian earthquake. However, according to the results of Carlisle M =5.0 earthquake by Beamish(1982), the real parts F u, C u change more significantly. 展开更多
关键词 horizontal field inter station transfer functions underground electric structure abnormal field normal field
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A New Approach for Segregation Control in Alloys by High Magnetic Field Gradients and Its Application in Functional Materials
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作者 LIU Tie WANG Qiang +3 位作者 LIU Yin GAO Peng-fei LOU Chang-sheng HE Ji-cheng 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2012年第S1期291-296,共6页
In this study,the effects of high magnetic field gradients on the segregation of alloying elements,crystallized phases,and particles in alloys during solidification process and corresponding microstructures were discu... In this study,the effects of high magnetic field gradients on the segregation of alloying elements,crystallized phases,and particles in alloys during solidification process and corresponding microstructures were discussed.It was confirmed that applying an external high magnetic field gradient during solidification process is an effective processing route for controlling segregation in alloys and then fabricating functional materials which have special mierostruetures and properties.Such controlling and fabrication were realized by controlling the migration of the alloying elements, crystallized phases,and particles in the liquid matrix on the basis of the Lorentz and magnetic forces. 展开更多
关键词 high magnetic field gradient SEGREGATION functional material Lorentz force magnetic force
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NONLINEAR TRANSIENT RESPONSE OF FUNCTIONALLY GRADED SHALLOW SPHERICAL SHELLS SUBJECTED TO MECHANICAL LOAD AND UNSTEADY TEMPERATURE FIELD 被引量:2
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作者 Yiming Fu Sumin Hu Yiqi Mao 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2014年第5期496-508,共13页
This paper is concerned with the transient deformation of functionally graded (FG) shallow spherical shells subjected to time-dependent thermomechanical load. Based on Timoshenko- Mindlin hypothesis and yon Karman n... This paper is concerned with the transient deformation of functionally graded (FG) shallow spherical shells subjected to time-dependent thermomechanical load. Based on Timoshenko- Mindlin hypothesis and yon Karman nonlinear theory, a set of nonlinear governing equations of motion for FG shallow spherical shells in regard to transverse shear deformation and all the inertia terms are established using Hamilton's principle. The collocation point method and Newmark- beta scheme in conjunction with the finite difference method are adopted to solve the governing equations of motion and the unsteady heat conduction equation numerically. In the numerical examples, the transient deflection and stresses of FG shallow spherical shells with various material properties under different loading conditions are presented. 展开更多
关键词 functionally graded materials unsteady temperature field transient deflection andstresses
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Flood Reduction Function of Paddy Rice Fields under Different Water Saving Irrigation Techniques 被引量:1
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作者 Joko Sujono 《Journal of Water Resource and Protection》 2010年第6期555-559,共5页
This study is conducted to investigate the function of paddy fields for flood reduction under different water saving irrigation techniques. A daily water balance component data including rainfall, percolation, and ove... This study is conducted to investigate the function of paddy fields for flood reduction under different water saving irrigation techniques. A daily water balance component data including rainfall, percolation, and overflow through the paddy field levee were collected from experimental paddy rice fields during rainy season cultivation. Results show that paddy field was very effective in flood reduction. More than 40% of rainfall could be stored in the paddy fields. However, the effectiveness of paddy fields in flood reduction was highly depends on the WSI technique used. Semi dry cultivation technique was the most effective one in terms of flood reduction. It retained the rainfall up to 55.7% (365 mm) of the total rainfall (636 mm) without reducing the yield. In terms of flood volume reduction, the alternate wetting and drying performed similarly with traditional continuous flooding, i.e., 37.2% and 40.8%, respectively. 展开更多
关键词 FLOOD REDUCTION function Water SAVING IRRIGATION PADDY field
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CHAINS OF FUNCTION SPACES OVER EUCLIDIAN SPACES AND LOCAL FIELDS
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作者 Zhaoxi Wang 《Analysis in Theory and Applications》 2009年第1期92-100,共9页
The Lipschitz class Lip(K, α) on a local field K is defined in [10], and an equivalent relationship between the Ho¨lder type space Cα(K)[9] and Lip(K,α) is given. In this note, we give a 'chain of function... The Lipschitz class Lip(K, α) on a local field K is defined in [10], and an equivalent relationship between the Ho¨lder type space Cα(K)[9] and Lip(K,α) is given. In this note, we give a 'chain of function spaces' over Euclidian space by defining higher order continuous modulus in R, and point out that there is no need of higher order continuous modulus for describing the chain of function spaces over local fields. 展开更多
关键词 local field Lipschitz class function space morder continuous modulus morder Lipschitz class
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Semi-supervised classification based on Markov Random Field and Robust Error Function
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作者 LIN Qing SHAN Ping-ping +1 位作者 WANG Shi-tong ZHAN Yong-zhao 《通讯和计算机(中英文版)》 2009年第4期1-5,共5页
关键词 半管理 MARKOV随机场 误差函数 能量函数
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Method of lines for temperature field of functionally graded materials 被引量:1
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作者 戴耀 孙琦 +2 位作者 郝贵祥 燕秀发 李永东 《Journal of Central South University》 SCIE EI CAS 2005年第S2期230-232,共3页
The finite element method (FEM) and the boundary element method (BEM) are often adopted. However, they are not convenient to spatially vary thermal properties of functionally graded material (FGM). Therefore, the meth... The finite element method (FEM) and the boundary element method (BEM) are often adopted. However, they are not convenient to spatially vary thermal properties of functionally graded material (FGM). Therefore, the method of lines (MOL) is introduced to solve the temperature field of FGM. The basic idea of the method is to semi-discretize the governing equation into a system of ordinary differential equations (ODEs) defined on discrete lines by means of the finite difference method. The temperature field of FGM can be obtained by solving the ODEs. The functions of thermal properties are directly embodied in these equations and these properties are not discretized in the domain. Thus, difficulty of FEM and BEM is overcome by the method. As a numerical example, the temperature field of a plane problem is analyzed for FGMs through varying thermal conductivity coefficient by the MOL. 展开更多
关键词 functionally GRADED MATERIALS METHOD of LINES TEMPERATURE field
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Effect of gradient magnetic field on physiochemistry functions of rice seedlings
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《Chinese Rice Research Newsletter》 1999年第1期10-10,共1页
Rice varieties Handao 2,Zhongbai 4,Han-jingzi,and Akihikari were treated with gradi-ent magnetic fileld to study the effect of gradi-ent field on rice.The magnetic field was madeup of 12 plots magnetic plates arranged... Rice varieties Handao 2,Zhongbai 4,Han-jingzi,and Akihikari were treated with gradi-ent magnetic fileld to study the effect of gradi-ent field on rice.The magnetic field was madeup of 12 plots magnetic plates arranged in eachother south and north pole.The magneticstrength was 0-40 mT.Each four varieties wasput under the magnetic plate 15 cm away,andwent through the magnetic field with the speedof 20 cm/s.The same varieties without thetreatment were used as CK.Both of the seedswere soaked in water for 48 h in room temper-ature,and then sprouted on the porcelain platewith absorbed water paper.When the 展开更多
关键词 Effect of gradient magnetic field on physiochemistry functions of rice seedlings
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Heun Functions Describing Fermions Evolving in Parallel Electric and Magnetic Fields
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作者 MARINA-AURA Dariescu CIPRIAN Dariescu 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第7期21-24,共4页
The present work deals with the behavior of fermions moving in a static magnetic induction and a time-harmonic electric field, both oriented along Oz. For the ultra-relativistic particles described by a Heun double co... The present work deals with the behavior of fermions moving in a static magnetic induction and a time-harmonic electric field, both oriented along Oz. For the ultra-relativistic particles described by a Heun double confluent equation, we derive the corresponding wave functions and the conserved current density components. 展开更多
关键词 exp Heun functions Describing Fermions Evolving in Parallel Electric and Magnetic fields
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Higher-order crack tip fields for functionally graded material plate with transverse shear deformation
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作者 Dianhui HOU Xiao CHONG +1 位作者 Guixiang HAO Yao DAI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2016年第6期695-706,共12页
The crack tip fields are investigated for a cracked functionally graded material (FGM) plate by Reissner's linear plate theory with the consideration of the transverse shear deformation generated by bending. The el... The crack tip fields are investigated for a cracked functionally graded material (FGM) plate by Reissner's linear plate theory with the consideration of the transverse shear deformation generated by bending. The elastic modulus and Poisson's ratio of the functionally graded plates are assumed to vary continuously through the coordinate y, according to a linear law and a constant, respectively. The governing equations, i.e., the 6th-order partial differential equations with variable coefficients, are derived in the polar coordinate system based on Reissner's plate theory. Furthermore, the generalized displacements are treated in a separation-of-variable form, and the higher-order crack tip fields of the cracked FGM plate are obtained by the eigen-expansion method. It is found that the analytic solutions degenerate to the corresponding fields of the isotropic homogeneous plate with Reissner's effect when the in-homogeneity parameter approaches zero. 展开更多
关键词 crack tip field Reissner's effect PLATE functionally graded material (FGM) eigen-expansion method
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