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PREPARATION AND SECOND-ORDER OPTICAL NONLINEARITY OF NOVEL PHENOXYSILICON NETWORKS BY SOL-GEL PROCESS 被引量:1
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作者 Xiao Huang Jian Wang Ling-zhi Zhang Zhi-gang Cai Zhao-xi Lianga 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2001年第1期39-44,共6页
Four phenoxysilicon networks for nonlinear optical (NLO) applications were designed and prepared by an extended sol-gel process without additional H2O and catalyst. All poled polymer network films possess high second-... Four phenoxysilicon networks for nonlinear optical (NLO) applications were designed and prepared by an extended sol-gel process without additional H2O and catalyst. All poled polymer network films possess high second-order nonlinear optical coefficients (d(33)) Of 10(-7)similar to 10(-8) esu. The investigation of NLO temporal stability at room temperature and elevated temperature (120 degreesC) indicated that these films exhibit high d(33) stability because the orientation of the chromophores are locked in the phenoxysilicon organic/inorganic networks. 展开更多
关键词 phenoxysilicon networks sol-gel process azobenzene chromophore stilbene chromophore second order optical nonlinearity
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EXISTENCE AND UNIQUENESS FOR THIRD ORDER NONLINEAR BOUNDARY VALUE PROBLEMS 被引量:5
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作者 WANG GUOCAN Department of Basic Science, Dalian Institute of Railway Technology, Dalian 116022 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 1996年第1期7-16,共10页
In this paper, the existence and uniqueness of solutions for boundary valueproblem x′′′=f(t, x, x′, x″), x(0)=A, x′(0)=B, g(x′(1), x″(1))=0 are studied byusing Volterra type operator and upper and lower soluti... In this paper, the existence and uniqueness of solutions for boundary valueproblem x′′′=f(t, x, x′, x″), x(0)=A, x′(0)=B, g(x′(1), x″(1))=0 are studied byusing Volterra type operator and upper and lower solutions. Our results improve someknown works. 展开更多
关键词 Third order nonlinear boundary value problem existence and uniqueness Volterra type operator upper and lower solutions.
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A Theoretical Study of Nonlinear Second-Order Optical Properties of Substituted Silanes 被引量:1
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作者 FENG Ji kang, WANG Hai chuan, WEI Jia you, XIAO Chang yong XU Wen guo and SUN Chia chung (Department of Chemistry and Institute of Theoretical Chemistry, Jilin University, Changchun, 130023) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1997年第1期51-60,共10页
On the basis of ZINDO method and according to the sum over states(SOS) expression, the program is devised for the calculation of nonlinear second order optical susceptibilites β ijk and studying how ... On the basis of ZINDO method and according to the sum over states(SOS) expression, the program is devised for the calculation of nonlinear second order optical susceptibilites β ijk and studying how different substituents on the phenyl ring attached to the atom silicon influence on the nonlinear second order optical properties of substituted silane series of molecules. The properties of (CH 3) 3Si? ?has been studied particularly. The effect of the length of silica chains on the calculated values has been studied too. The regularity summarized from the calculated results has been explained micromechanically. 展开更多
关键词 Substituted silanes Nonlinear second order optical susceptibility ZINDO SOS
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Travelling solitary wave solutions for the generalized Burgers-Huxley equation with nonlinear terms of any order 被引量:2
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作者 邓习军 燕子宗 韩立波 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第8期3169-3173,共5页
In this paper, the travelling wave solutions for the generalized Burgers-Huxley equation with nonlinear terms of any order are studied. By using the first integral method, which is based on the divisor theorem, some e... In this paper, the travelling wave solutions for the generalized Burgers-Huxley equation with nonlinear terms of any order are studied. By using the first integral method, which is based on the divisor theorem, some exact explicit travelling solitary wave solutions for the above equation are obtained. As a result, some minor errors and some known results in the previousl literature are clarified and improved. 展开更多
关键词 travelling wave solutions first integral method generalized Burgers-Huxley equation with nonlinear terms of any order
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OSCILLATION CRITERIA FOR SECOND ORDER NONLINEAR DIFFERENTIAL EQUATION WITH DAMPING 被引量:1
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作者 罗辉 庄容坤 +3 位作者 郭兴明Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 P.R.China 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第4期441-448,共8页
By the generalized Riccati transformation and the integral averaging technique, some sufficient conditions of oscillation of the solutions for second order nonlinear differential equations with damping were discussed.... By the generalized Riccati transformation and the integral averaging technique, some sufficient conditions of oscillation of the solutions for second order nonlinear differential equations with damping were discussed.Some sufficient oscillation criteria for previous equations were built up.Some oscillation criteria have been expanded and strengthened in some other known results. 展开更多
关键词 second order nonlinear differential equation with damping OSCILLATION Riccati transformation integral averaging technique
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A New Generalized Riccati Equation Rational Expansion Method to Generalized Burgers-Fisher Equation with Nonlinear Terms of Any Order 被引量:2
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作者 ZHANG Xiao-Ling WANG Jing ZHANG Hong-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期779-786,共8页
In this paper, based on a new more general ansitz, a new algebraic method, named generalized Riccati equation rational expansion method, is devised for constructing travelling wave solutions for nonlinear evolution eq... In this paper, based on a new more general ansitz, a new algebraic method, named generalized Riccati equation rational expansion method, is devised for constructing travelling wave solutions for nonlinear evolution equations with nonlinear terms of any order. Compared with most existing tanh methods for finding travelling wave solutions, the proposed method not only recovers the results by most known algebraic methods, but also provides new and more general solutions. We choose the generalized Burgers-Fisher equation with nonlinear terms of any order to illustrate our method. As a result, we obtain several new kinds of exact solutions for the equation. This approach can also be applied to other nonlinear evolution equations with nonlinear terms of any order. 展开更多
关键词 generalized Riccati equation rational expansion method generalized Burgers-Fisher equation with nonlinear terms of any order symbolic computation
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ON THE BOUNDEDNESS AND THE STABILITY PROPERTIES OF SOLUTION OF CERTAIN FOURTH ORDER DIFFERENTIAL EQUATIONS 被引量:1
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作者 俞元洪 陈文灯 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1990年第9期881-887,共7页
This paper investigates equation (1) in twocases:(i)P=0, (ii)P satisfies|P (i,x,y,z,w)<(A+|y|+|z|+|w|)q(t).whereq(t) is a nonnegative function of t. For case (i) the asymptotic stability in the large of the trivial... This paper investigates equation (1) in twocases:(i)P=0, (ii)P satisfies|P (i,x,y,z,w)<(A+|y|+|z|+|w|)q(t).whereq(t) is a nonnegative function of t. For case (i) the asymptotic stability in the large of the trivial solution x=0 is investigated and for case (ii) the boundedness result is obtained for solutions of equation (1). These results improve and include several well-known results. 展开更多
关键词 nonlinear differential equations of the four order BOUNDEDNESS stability
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ON THE BOUNDEDNESS AND THE STABILITY RESULTS FOR THE SOLUTION OF CERTAIN FOURTH ORDER DIFFERENTIAL EQUATIONS VIA THE INTRINSIC METHOD 被引量:1
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作者 Cemil TUNC Aydin TIRYAKI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1996年第11期1039-1049,共11页
In this paper, we first present constructing a Lyapunov function for (1. 1) and then we show the asymptotic stability in the large of the trivial solution x=0 for case p≡ 0,and the boundedness result of the sol... In this paper, we first present constructing a Lyapunov function for (1. 1) and then we show the asymptotic stability in the large of the trivial solution x=0 for case p≡ 0,and the boundedness result of the solutions of (1 .1 ) for case p≠0. These results improve sveral well-known results. 展开更多
关键词 nonlinear differential equations of the fourth order Lyapunovfunction STABILITY BOUNDEDNESS intrinsic method
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Nonlinear profile order for three-dimensional hybrid radial acquisition applied to self-gated free-breathing cardiac cine MRI
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作者 Yanchun Zhu Pascal Spincemaille +5 位作者 Jing Liu Shuo Li Thanh D Nguyen Martin R Prince Yaoqin Xie Yi Wang 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第1期568-573,共6页
This paper presents a nonlinear profile order scheme for three-dimensional(3D) hybrid radial acquisition applied to self-gated, free-breathing cardiac cine magnetic resonance imaging(MRI). In self-gated, free-brea... This paper presents a nonlinear profile order scheme for three-dimensional(3D) hybrid radial acquisition applied to self-gated, free-breathing cardiac cine magnetic resonance imaging(MRI). In self-gated, free-breathing cardiac cine MRI,respiratory and cardiac motions are unpredictable during acquisition, especially for retrospective reconstruction. Therefore,the non-uniformity of the k-space distribution is an issue of great concern during retrospective self-gated reconstruction. A nonlinear profile order with varying azimuthal increments was provided and compared with the existing golden ratio-based profile order. Optimal parameter values for the nonlinear formula were chosen based on simulations. The two profile orders were compared in terms of the k-space distribution and phantom and human image results. An approximately uniform distribution was obtained based on the nonlinear profile order for persons with various heart rates and breathing patterns.The nonlinear profile order provides more stable profile distributions and fewer streaking artifacts in phantom images. In a comparison of human cardiac cine images, the nonlinear profile order provided results comparable to those provided by the golden ratio-based profile order, and the images were suitable for diagnosis. In conclusion, the nonlinear profile order scheme was demonstrated to be insensitive to various motion patterns and more useful for retrospective reconstruction. 展开更多
关键词 nonlinear profile order hybrid radial SELF-GATING cardiac cine MRI
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THE SYNTHESIS OF NEW POLED CROSSLINKED POLYMETHACRYLATES AND THEIR SECOND ORDER NONLINEAR OPTICAL PROPERTIES
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作者 颜星中 陈用烈 +3 位作者 梁兆熙 蔡志岗 杨佩青 罗挺 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1996年第4期346-354,共9页
Films were prepared from mixtures of copolymers of 4-nitro-4'-[N-methylacryloyloxyethyl, N'-ethyl] amino azobenzene with glycidyl methacrylate (chromophore content: 6 mol%) and copolymers containing anhydride ... Films were prepared from mixtures of copolymers of 4-nitro-4'-[N-methylacryloyloxyethyl, N'-ethyl] amino azobenzene with glycidyl methacrylate (chromophore content: 6 mol%) and copolymers containing anhydride units, which was obtained by the reaction of 4-nitro-4'-[N-hydroxyethyl, N'-ethyl] amino azobenzene with polymethacryloyl chloride (chromophore content: 25 mol %). During thermal poling process the anhydride reacts with the epoxy group and the resulting crosslinked network structure will stabilize the second harmonic generation in the poled film. The second harmonic generation of the poled film shows a maximum with the variation of composition this is presumed to be due to the effects of the increasing of concentration, orientation order as well as orientation stability of chromophore groups during crosslinking. 展开更多
关键词 second order nonlinear optics poled polymers Disperse Red 1 methacrylate copolymers
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SECOND ORDER NONLINEAR OPTICAL PROPERTIES OF DICYANOPYRAZINES
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作者 Cheng YE Zhi Ming FENG Yah Jun CHEN Jia Fu WANG Hai Ou DONG (Institute of Chemistry, Academia Sinica, Beijing 100080) Dept. of Chemistry, Branch Campus of Peking University. 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第10期765-768,共4页
Second order nonlinear optical active 2,3-dichloro-5,6-dicyanopyrazine (DCDCP) and its monoamine-substituted derivatives had been synthesized. Their facile synthesis, high melt point, high incidence af substantial SHG... Second order nonlinear optical active 2,3-dichloro-5,6-dicyanopyrazine (DCDCP) and its monoamine-substituted derivatives had been synthesized. Their facile synthesis, high melt point, high incidence af substantial SHG activity and increased transparency inthe blue and near infrared make this class compounds appealling for further investigation. 展开更多
关键词 SHG SECOND order NONLINEAR OPTICAL PROPERTIES OF DICYANOPYRAZINES NLO
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Crystal Structure and Third order Nonlinear Optical Properties of cis-Configuration Biferrocene Trinuclear Complexes
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作者 WU Jie-ying TIAN Yu-peng +1 位作者 XIE Fu-xin NI Shi-sheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1999年第3期218-225,共8页
The syntheses and characterization of novel biferrocene trinuclear complexes of Schiff base ligand, S methyl N (ferrocenyl 1 methyl methylidene)dithiocarbazate [hereafter abbreviated as HL (1)], are described. The X r... The syntheses and characterization of novel biferrocene trinuclear complexes of Schiff base ligand, S methyl N (ferrocenyl 1 methyl methylidene)dithiocarbazate [hereafter abbreviated as HL (1)], are described. The X ray diffraction studies have established the structures of PdL 2 (3) and CuL 2 (4). The geometry of Pd(Ⅱ) in (3) is close to a square plane and in the novel cis configuration the two ferrocene moieties are in cis configuration, while that of Cu(Ⅱ) in (4) is close to a tetrahedral configuration. The electrochemical measurements suggested that the square planar configuration of Ni(Ⅱ) and Pd(Ⅱ) moieties can effectively transmit the redox effects of the ferrocene moieties, while the tetrahedral configuration of the Cu(Ⅱ) complex can not transmit the redox effects. The degenerate four wave mixing (DFWM) measurements showed that the complexes exhibit obviously nonlinear optical (NLO) response. The magnitude of their third order NLO susceptibility can be explained by their structure and electrochemical properties. 展开更多
关键词 ELECTROCHEMISTRY cis Configuration biferrocene Third order nonlinear optical property
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THE GLOBAL SOLUTIONS FOR A FOURTH ORDER NONLINEAR SCHRaINGER EQUATION
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作者 冯学尚 《Acta Mathematica Scientia》 SCIE CSCD 1995年第2期196-206,共11页
Is this Paper, the global existence of smooth solutions to the Antial value problem for the fourth order nonlinear Schrodinger equation in the Lax hierarchy of the nonlinear fSchrodinger equation(NLS equation) is esta... Is this Paper, the global existence of smooth solutions to the Antial value problem for the fourth order nonlinear Schrodinger equation in the Lax hierarchy of the nonlinear fSchrodinger equation(NLS equation) is established by using the so-called continuation method and delicate a priori estimate. In addition, the asylnptotic properties of the solutions as|×|+∞ are discussed. 展开更多
关键词 Forth order nonlinear schrodinger equation Initial value problem Global existence Asymptotic behavior.
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Oscillation Theorems for Second Order Damped Nonlinear Differential Equations
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作者 HEWan-sheng LIWan-tong 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2005年第1期1-9,共9页
Several oscillation criteria are given for the second order nonlinear differential equation with damped term of the form [α(t)(y'(t))σ]' +p(t)(y'(t))σ+ q(t)f(y(t)) = 0, where α∈C(R, (0,∞)), p(t) and ... Several oscillation criteria are given for the second order nonlinear differential equation with damped term of the form [α(t)(y'(t))σ]' +p(t)(y'(t))σ+ q(t)f(y(t)) = 0, where α∈C(R, (0,∞)), p(t) and q(t) are allowed to change sign on [t0, ∞), and f∈C1 (R, R) such that xf(x) > 0 for x ≠0. Our results improve and extend some known oscillation criteria. Examples are inserted to illustrate our results. 展开更多
关键词 OSCILLATION second order nonlinear differential equation DAMPING
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Stabilizing controller design for nonlinear fractional order systems with time varying delays
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作者 AZIZI Abdollah FOROUZANFAR Mehdi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2021年第3期681-689,共9页
To deal with stabilizing of nonlinear affine fractional order systems subject to time varying delays,two methods for finding an appropriate pseudo state feedback controller are discussed.In the first method,using the ... To deal with stabilizing of nonlinear affine fractional order systems subject to time varying delays,two methods for finding an appropriate pseudo state feedback controller are discussed.In the first method,using the Mittag-Lefler function,Laplace transform and Gronwall inequality,a linear stabilizing controller is derived,which uses the fractional order of the delayed system and the upper bound of system nonlinear functions.In the second method,at first a sufficient stability condition for the delayed system is given in the form of a simple linear matrix inequality(LMI)which can easily be solved.Then,on the basis of this result,a stabilizing pseudo-state feedback controller is designed in which the controller gain matrix is easily computed by solving an LMI in terms of delay bounds.Simulation results show the effectiveness of the proposed methods. 展开更多
关键词 fractional order nonlinear system time varying delay state feedback control linear matrix inequality(LMI) stabilizing
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OSCILLATION THEOREMS FOR SECOND ORDER NONLINEAR DIFFERENTIAL EQUATIONS WITH DAMPING
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作者 陈伯山 《Acta Mathematica Scientia》 SCIE CSCD 1991年第4期409-416,共8页
Some new oscillation theorems are established for the second order nonlinear differential equations with damping of the form where p(t) and q(t) are allowed to change sign on [t0,∞).
关键词 OSCILLATION THEOREMS FOR SECOND order NONLINEAR DIFFERENTIAL EQUATIONS WITH DAMPING
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Synthesis and Characterization of Nonlinear Optical Material of Substituted Diacetylenes with Azophenyl Group and Pyrimidine Ring
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作者 王江洪 余从煊 沈玉全 《Journal of Beijing Institute of Technology》 EI CAS 1996年第2期129+123-129,共8页
?-(2-methylthio -4 -methyl -5 -pyrimidinyl)-2. 4 - pentadiyn- 1 -ol- (4- N. N-dimethylamino-azobenzene -4' -sulfonate) (PDABS - 1 ). ②5 -(2 -methylthio -4 -methyl -5-pyrimidinyl)- 2.4 -pentadiyn- 1 -ol - (azobenz... ?-(2-methylthio -4 -methyl -5 -pyrimidinyl)-2. 4 - pentadiyn- 1 -ol- (4- N. N-dimethylamino-azobenzene -4' -sulfonate) (PDABS - 1 ). ②5 -(2 -methylthio -4 -methyl -5-pyrimidinyl)- 2.4 -pentadiyn- 1 -ol - (azobenzene - 4 -sulfonate) (PDABS -2 ). ③2. 4 -hexadiyn - 1 -ol-6- (4 - N, N-dimethylamino-azobenzene-4'-sulfonate) (HDABS - 1 ), ④2. 4 -hexadiyn - 1-ol -6 - (azobenzene4-sulfonate) (HDABS-2), the four new compounds are synthesize. The structures of the new compounds have been demonstrdted by elemental analysis. IR(KBr). 1H-NMR (CD3CO/TMS),MS. Their X(3), d33. βμ and the fabrication of their polarization orientated thin film also have ben reported in this paper. 展开更多
关键词 azophenyl PYRIMIDINE DIACETYLENE third order nonlinearity
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Asymptotic Calculation of the Wave Trough Exceedance Probabilities in A Nonlinear Sea 被引量:1
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作者 WANG Ying-guang 《China Ocean Engineering》 SCIE EI CSCD 2018年第2期189-195,共7页
This paper concerns the calculation of the wave trough exceedance probabilities in a nonlinear sea. The calculations have been carried out by incorporating a second order nonlinear wave model into an asymptotic method... This paper concerns the calculation of the wave trough exceedance probabilities in a nonlinear sea. The calculations have been carried out by incorporating a second order nonlinear wave model into an asymptotic method. This is a new approach for the calculation of the wave trough exceedance probabilities, and, as all of the calculations are performed in the probability domain, avoids the need for long time-domain simulations. The proposed asymptotic method has been applied to calculate the wave trough depth exceedance probabilities of a sea state with the surface elevation data measured at the coast of Yura in the Japan Sea. It is demonstrated that the proposed new method can offer better predictions than the theoretical Rayleigh wave trough depth distribution model. The calculated results by using the proposed new method have been further compared with those obtained by using the Arhan and Plaisted nonlinear distribution model and the Toffoli et al.’s wave trough depth distribution model, and its accuracy has been once again substantiated. The research findings obtained from this study demonstrate that the proposed asymptotic method can be readily utilized in the process of designing various kinds of ocean engineering structures. 展开更多
关键词 wave trough depth second order nonlinear wave model asymptotic method measured data
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Relationship between Dislocation Density in P91 Steel and Its Nonlinear Ultrasonic Parameter 被引量:3
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作者 Ye-qing CAI Jin-zhong SUN +2 位作者 Cheng-jie LIU Shi-wei MA Xi-cheng WEI 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2015年第11期1024-1030,共7页
P91 steel is an important bearing material used in nuclear power plants. The study of its mechanical degradation behavior is important for ensuring safe operation. The relationship between the dislocation density of P... P91 steel is an important bearing material used in nuclear power plants. The study of its mechanical degradation behavior is important for ensuring safe operation. The relationship between the dislocation density of P91 steel under different strains and the corresponding nonlinear ultrasonic parameter β was studied. The dislocation density of strained samples was estimated by X-ray diffraction. Nonlinear ultrasonic testing was conducted to evaluate β, showing that this value increased with increasing dislocation density induced by different tensile elongations. It was shown that the ultrasonic secondharmonic generation technique can effectively evaluate the degradation behavior of metallic materials, and the prediction of the residual life of bearing parts in service can be made based on β and the dislocation density. 展开更多
关键词 dislocation density P91 steel nonlinear ultrasonic second order harmonic
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Density Functional Studies on Isonicotinato Lead(II) Complex [Pb(C_5H_4NCOO)_2] 被引量:1
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作者 ZHAO Pu-Su JIAN Fang-Fang +1 位作者 LI Chun-Lei ZHENG Jian 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第6期657-662,共6页
The title compound of isonicotinato lead(Ⅱ) [Pb(C5H4NCOO)2] has been optimized at B3LYP/LANL2DZ level of theory and calculated results show that the lead(Ⅱ) ion adopts 4-coordinate geometry. Atomic charge dist... The title compound of isonicotinato lead(Ⅱ) [Pb(C5H4NCOO)2] has been optimized at B3LYP/LANL2DZ level of theory and calculated results show that the lead(Ⅱ) ion adopts 4-coordinate geometry. Atomic charge distributions indicate that during forming the title compound, each isonicotinic acid ion transfers -0.452 e to lead(Ⅱ) ion. The electronic spectra calculations show that there exist two absorption bands and the electronic transitions are mainly derived from the contribution of intraligand π→π^* transition and ligand-to-metal charge transfer (LMCT) transition. The thermodynamic properties of the title compound at different temperatures have been calculated and corresponding relations between property and temperature have also been obtained. The calculation of the second order optical nonlinearity was carried out, and the molecular hyperpolarizability was 3.62365^*10^-30 esu. 展开更多
关键词 isonicotinato lead(Ⅱ) complex density functional theory electronic spectra thermal property analysis the second order optical nonlinearity
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