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最子力学方面的几种实验
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《世界经济科技》 1991年第36期49-53,共5页
关键词 子力 实验 子力
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反应力应变岩石力学在工程中应用的简明论述 被引量:1
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作者 刘国霖 《三峡大学学报(自然科学版)》 CAS 2012年第6期44-47,共4页
反应力应变岩石力学,是岩石力学发展中的创新思路.地壳表层岩体在气温下降环境中会产生收缩,产生向表部的拉力,这是一反向力流,谓之反应力.它是一种匿动力,是一种暗能,在边坡区,它与岩体重力组合成向地表的水平拉张合力,并可导致节理扩... 反应力应变岩石力学,是岩石力学发展中的创新思路.地壳表层岩体在气温下降环境中会产生收缩,产生向表部的拉力,这是一反向力流,谓之反应力.它是一种匿动力,是一种暗能,在边坡区,它与岩体重力组合成向地表的水平拉张合力,并可导致节理扩张,以致产生脆弹性破裂,发生规模不等的振动,派生向外顶冲的波子力,成为重要的反应力因素.高边坡区岩体,一般处于三维受压的应力状态,但当气温剧降时,边坡区应力环境,就变为二维受压,一维受拉的拉张圆状态,甚至产生拉裂剪切的脆断破裂与灾变.高边坡区的应力态势,因气温规律性变迁与骤变,使反应力作用,呈现大、小、有、无的往复变化,所以高边坡区岩体的岩石力学特性和水力学特性,处于缓慢的累进破坏与不断劣化的衰变过程中. 展开更多
关键词 反应力应变 匿动力 暗能 拉平势场 波子力 累进衰变 拉裂脆断
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NOVEL IMMERSED BOUNDARY-LATTICE BOLTZMANN METHOD BASED ON FEEDBACK LAW 被引量:1
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作者 李秀娟 赵荣国 钟诚文 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期179-186,共8页
The lattice Boltzmann method (LBM) and the immersed boundary method (IBM) are alternative, com- putational techniques for solving complex fluid dynamics systems, and can take the place of the Navier-Stokes(N- S)... The lattice Boltzmann method (LBM) and the immersed boundary method (IBM) are alternative, com- putational techniques for solving complex fluid dynamics systems, and can take the place of the Navier-Stokes(N- S) equation. This paper proposes a novel immersed boundary-lattice Boltzmann method (IB-LBM) based on the feedback law. The method uses the immersed boundary concept in the LBM framework to capture the coupling between a body with complex geometry and a uniform fluid, Then, the flows around a stationary circular cylinder and two circular cylinders in a side by side arrangement are simulated by using the method. Results are agreed well with the benchmark data, so, the capability of the method for complex geometry is demonstrated. Different from the conventional IB-LBM, which uses the Hook's law or the direct forcing method to compute the interae- tion force, the method uses the feedback law--the feedback of velocity field and displacement information to calculate the force, thus ensuring the method has advantages of easy implementation and full parallelism. 展开更多
关键词 computational fluid dynamics lattice Boltzmann method immersed boundary method feedback law circular cylinder
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Edge enhancement of gravity anomalies and gravity gradient tensors using an improved small sub-domain filtering method 被引量:4
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作者 蒋甫玉 高丽坤 《Applied Geophysics》 SCIE CSCD 2012年第2期119-130,233,共13页
In order to enhance geological body boundary visual effects in images and improve interpretation accuracy using gravity and magnetic field data, we propose an improved small sub-domain filtering method to enhance grav... In order to enhance geological body boundary visual effects in images and improve interpretation accuracy using gravity and magnetic field data, we propose an improved small sub-domain filtering method to enhance gravity anomalies and gravity gradient tensors. We discuss the effect of Gaussian white noise on the improved small sub-domain filtering method, as well as analyze the effect of window size on geological body edge recognition at different extension directions. Model experiments show that the improved small sub-domain filtering method is less affected by noise, filter window size, and geological body edge direction so it can more accurately depict geological body edges than the conventional small sub-domain filtering method. It also shows that deeply buried body edges can be well delineated through increasing the filter window size. In application, the enhanced gravity anomalies and calculated gravity gradient tensors of the Hulin basin show that the improved small sub-domain filtering can recognize more horizontal fault locations than the conventional method. 展开更多
关键词 Small sub-domain filter gravity gradient tensor edge enhancement gravity anomaly
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HIV-1蛋白酶的质子化状态 被引量:1
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作者 洪正平 王秀娥 《原子与分子物理学报》 CAS CSCD 北大核心 2011年第3期577-580,共4页
将分子动力学模拟和分子力学-泊松/波耳兹曼方法相结合,研究在HIV蛋白酶和抑制剂ABT-538的复合物中的不同质子化位置.结果表明:不同的质子化状态对蛋白酶的温度因子、蛋白酶和抑制剂的结合自由能及氢键都有很大影响.用分子力学-泊松/波... 将分子动力学模拟和分子力学-泊松/波耳兹曼方法相结合,研究在HIV蛋白酶和抑制剂ABT-538的复合物中的不同质子化位置.结果表明:不同的质子化状态对蛋白酶的温度因子、蛋白酶和抑制剂的结合自由能及氢键都有很大影响.用分子力学-泊松/波耳兹曼方法计算显示:在B链中,25号天冬氨酸OD1氧原子被质子化的结合自由能最强,计算得到的温度因子和实验值比较吻合.另外,由氢键分析看出:在此质子化状态中,药物和蛋白酶、药物和W301水分子、W301水分子和蛋白酶形成的氢键在整个动力学模拟过程中最稳定. 展开更多
关键词 质子化 分子动力学 子力学-泊松/耳兹曼表面积方法 HIV蛋白酶 氢键
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Parseval Theory of Complex Wavelet Transform for Wavelet Family Including Rotational Parameters 被引量:1
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作者 ZHOU Nan-Run JIA Fang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第9期598-602,共5页
A rotational parameter Rθ has been introduced to complex wavelet transform (CWT). The rotational CWT (RCWT) corresponds to a matrix element 〈φ|U2(θ;μ;κ)[F〉 in the context of quantum mechanics, where U2(... A rotational parameter Rθ has been introduced to complex wavelet transform (CWT). The rotational CWT (RCWT) corresponds to a matrix element 〈φ|U2(θ;μ;κ)[F〉 in the context of quantum mechanics, where U2(θ;μ;κ) is a two-mode rotational displacing-squeezing operator in the 〈η| representation. Based on this, the Parseval theorem and the inversion formula of RCWT have been proved. The concise proof not only manifestly shows the merit of Dirac's representation theory but also leads to a new orthogonal property of complex mother wavelets in parameter space. 展开更多
关键词 complex wavelet transform representation theory quantum mechanics
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Side lobes of wavelets impact identification of thin sand bodies 被引量:7
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作者 Huang Junbin Gao Lijun Gao Yong 《Applied Geophysics》 SCIE CSCD 2007年第2期111-117,共7页
Recently, we found that side lobes of wavelets have a large impact on the identification of thin sand reservoirs when studying some gas fields in a basin in Northwest China. Reflections from the top of the H Formation... Recently, we found that side lobes of wavelets have a large impact on the identification of thin sand reservoirs when studying some gas fields in a basin in Northwest China. Reflections from the top of the H Formation, in which there are gas-bearing thin sand bodies, have the main wavelet lobe between two weak peak side lobes. The lower one always mixes with another peak reflected from the top of a thin sand reservoir. That makes it difficult to identify the sand reservoir. In order to solve this, many forward models were set up using typical well logs. 2D synthetic profiles were produced using Ricker wavelets to study the relationships between the effects of wavelet side lobes and thin sand position and frequency and between amplitude and the thin sand body. We developed the following conclusions: First, it is easier to identify thin sands in a shallower position. Second, a good way to tell sand body reflections from side lobes is by comparing profiles with different frequency windows. Third, it is helpful and effective to describe sand extent using amplitude attributes. 展开更多
关键词 wavelet side lobe Ricker wavelet RESOLUTION AMPLITUDE thin sand body.
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Application of Bipartite Entangled States to Quantum Mechanical Version of Complex Wavelet Transforms 被引量:1
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作者 FAN Hong-Yi LU Hai-Liang XU Xue-Fen 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第4期609-613,共5页
We introduce the bipartite entangled states to present a quantum mechanical version of complex wavelet transform. Using the technique of integral within an ordered product of operators we show that the complex wavelet... We introduce the bipartite entangled states to present a quantum mechanical version of complex wavelet transform. Using the technique of integral within an ordered product of operators we show that the complex wavelet transform can be studied in terms of various quantum state vectors in two-mode Fock space. In this way the creterion for mother wavelet can be examined quantum-mechanically and therefore more deeply. 展开更多
关键词 entangled states complex wavelet transform
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Fractional Fourier Transformation for Quantum Mechanical Wave Functions Studied by Virtue of IWOP Technique 被引量:1
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作者 FANHong-YI FANYue 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第4期417-420,共4页
Starting from the optical fractional Fourier transform (FFT) and using the technique of integration withinan ordered product of operators we establish a formalism of FFT for quantum mechanical wave functions. In doing... Starting from the optical fractional Fourier transform (FFT) and using the technique of integration withinan ordered product of operators we establish a formalism of FFT for quantum mechanical wave functions. In doing so, theessence of FFT can be seen more clearly, and the FFT of some wave functions can be derived more directly and concisely.We also point out that different FFT integral kernels correspond to different quantum mechanical representations. Theyare generalized FFT. The relationship between the FFT and the rotated Wigner operator is studied by virtue of theWeyl ordered form of the Wigner operator. 展开更多
关键词 fractional Fourier transformation IWOP technique Weyl ordering
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Bond interface crack propagation of fresh foundation concrete and rock under blasting load 被引量:1
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作者 WU Liang LU Wen-bo ZHONG Dong-wang 《Journal of Coal Science & Engineering(China)》 2009年第1期61-65,共5页
According to concrete age, the dynamic stress intensity factors of bond interface crack of concrete-rock was calculated. Result shows that the propagation of concreteinterface crack is mainly caused by tensile stress ... According to concrete age, the dynamic stress intensity factors of bond interface crack of concrete-rock was calculated. Result shows that the propagation of concreteinterface crack is mainly caused by tensile stress and shear stress for stress wave reflection. With the growth of concrete age, interface crack fracture toughness increases, and itscapacity of resisting blasting load strengthens. Therefore, blasting vibration should bestrictly controlled for fresh concrete. 展开更多
关键词 fresh concrete dynamic stress intensity factors numerical calculation
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Conformal Wavelet Finite-difference Time-domain Algorithm for Analysis of Milimeter Wave Attenuation on Coplanar Waveguide
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作者 DAI Hong-quan CHEN Hai-yan 《Semiconductor Photonics and Technology》 CAS 2007年第3期206-209,共4页
Addressed is the calculation of millimeter wave attenuation on coplanar waveguide(CPW). A novel conformal wavelet finite-difference time-domain(CWFDTD) algorithm is proposed with emphasis on its application in calcula... Addressed is the calculation of millimeter wave attenuation on coplanar waveguide(CPW). A novel conformal wavelet finite-difference time-domain(CWFDTD) algorithm is proposed with emphasis on its application in calculation of millimeter wave attenuation on CPW, which is the combination of conformal algorithm dealing with the deformed cell with Wavelet-FDTD using multi-resolution analysis(MRA). Derived is the difference formulation for multi-resolution time domain(MRTD) based on Daubechies wavelets, and also given is the stability conditions for wavelet-FDTD algorithm. To validate its accuracy and efficiency, this novel method is applied to calculate the millimeter wave attenuation on lithium niobate CPW. Numerical results demonstrate that this new CWFDTD algorithm has the same accuracy with the conformal finite-difference time-domain(CFDTD) and conformal finite-difference time-domain based on alternating-direction implicit method(ADI-CFDTD), but saves computational time and computer memory. 展开更多
关键词 millimeter wave attenuation conformal wavelet FDTD algorithm multi-resolution analysis multi-resolution time domain coplanar waveguide
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ULTRASONIC INPUT OUTPUT CHARACTERISTICS FOR TRANSMITTING AND RECEIVING CONTACT TYPE TRANSDUCERS COUPLED TO A TIMOSHENKO BEAM
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作者 Liu Tierang Department of Aircraft Engineering,NUAA29 Yudao Street, Nanjing 210016, P. R. China) 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第1期49-56,共8页
Acousto ultrasonic input output characteristics for transmitting and receiving contact type transducers coupled to a Timoshenko beam waveguide are considered. By means of a multiple integral transform method and co... Acousto ultrasonic input output characteristics for transmitting and receiving contact type transducers coupled to a Timoshenko beam waveguide are considered. By means of a multiple integral transform method and contour integration technique, the spectral response of the normal contact force between the receiving transducer and the wave guide, due to an arbitrary input pulse excited by the transmitting transducer, is expressed as a form of explicitly physical interpretations. Time histories of the response are then obtained through the inversion of the spectra by a fast Fourier transform (FFT) method. Finally, some numerical results are presented in diagrams, from which the effects on the mass of the receiver, the distance between the two transducers, and the input pulse width on the output are discussed. From the numerical calculation and the nature of the whole analysis it is shown that the analytical method presented in this paper is not only effective but also extendible to the more general cases. 展开更多
关键词 stress wave ULTRASONIC transducers stress wave factor material evaluation
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Elliptic Equation and Its Direct Applications to Nonlinear Wave Equations
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作者 FUZun-Tao CHENZhe +1 位作者 LIUShi-Da LIUShi-Kuo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第5期675-680,共6页
Elliptic equation is taken as an ansatz and applied to solve nonlinear wave equations directly. More kinds of solutions are directly obtained, such as rational solutions, solitary wave solutions, periodic wave solutio... Elliptic equation is taken as an ansatz and applied to solve nonlinear wave equations directly. More kinds of solutions are directly obtained, such as rational solutions, solitary wave solutions, periodic wave solutions and so on.It is shown that this method is more powerful in giving more kinds of solutions, so it can be taken as a generalized method. 展开更多
关键词 elliptic equation Jacobi elliptic function nonlinear equation periodic wave solution
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Effects of Extension and Overlap of Wavefunctions on Plasmon Modes in Symmetric Double—Quantum—Well Structures
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作者 LIUXin-Hai WANGXue-Hua 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第2期227-230,共4页
We investigate the effects of extension and overlap of wavefunctions on the dispersion relations of plasmon modes in symmetric double-quantum-well structures. We compare the approximate results in two-dimensional laye... We investigate the effects of extension and overlap of wavefunctions on the dispersion relations of plasmon modes in symmetric double-quantum-well structures. We compare the approximate results in two-dimensional layer-gas (2DLG) model with the exact ones where the extension and overlap of the wavefunctions are included. Our numerical results show that the 2DLG model is a good approximation only in the wide barrier case in the long wavelength limit. When the barrier is thin, the extension and overlap of the wavefunctions cannot be neglected. We also show that the long wavelength gap of the inter-subband mode is proportional to the energy difference between the ground and the first excited energy levels. 展开更多
关键词 quantum wells collective excitations PLASMONS
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A Kind of Three-Mode Entangled States of Continuum Variables Generated by Beam Splitter and Parametric Down-Conversion Amplifier
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作者 JIANGNian-Quan FANHong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期208-212,共5页
In 3-mode Fock space we find a new tripartite entangled state |α,γ 】 λ,which make up a new quantum mechanical representation. The state |α,γ 】 λ, can be generated byusing the setup composing of a beam splitter... In 3-mode Fock space we find a new tripartite entangled state |α,γ 】 λ,which make up a new quantum mechanical representation. The state |α,γ 】 λ, can be generated byusing the setup composing of a beam splitter and a parametric down-conversion amplifier. Applicationof the state is briefly discussed. 展开更多
关键词 tripartite entangled state beam splitter parametric down-conversionamplifier
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Effects of heavy ions on kinetic Alfven waves
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作者 YANGLei WUDe-Jin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第2期325-332,共8页
Kinetic Alfven Wave (KAW) is one of the low-frequency electromagnetic fluctuations that are identified extensively in space plasmas by in situ observations of satellites and has been an interesting topic for discussio... Kinetic Alfven Wave (KAW) is one of the low-frequency electromagnetic fluctuations that are identified extensively in space plasmas by in situ observations of satellites and has been an interesting topic for discussion widely in the fields of laboratory, space, and astrophysical plasmas because of its potential importance in plasma particle energization. Some satellite observations show that the number density ratio of the oxygen ions to the ambient plasma is 30% similar to 50%, sometimes, even as high as 80%. In this paper, effects of heavy ion species on KAWs are studied in a low-beta plasma. The results show that heavy ions not only considerably reduce the propagation speed of KAWs, but also remarkably influence the parallel component of perturbed electric field of KAWs (to the ambient magnetic field). The ratio of parallel to perpendicular components of perturbed field decreases (or increases) with the heavy ion abundance for KAWs dominated by the electron inertial length (or by ion acoustic gyroradius). In particular, the resonant condition of KAWs with thermal electrons is modified by the heavy ion species. 展开更多
关键词 space plasma heavy ions kinetic Alfven wave dispersion relation
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Non-adiabatic Couplings Induced Complex-Forming Mechanism in H+MgH^(+)→Mg^(+)+H_(2) Reaction
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作者 Bayaer Buren Ye Mao +1 位作者 Zijiang Yang Maodu Chen 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第2期345-352,I0003,共9页
A chemical process may involve multiple adiabatic electronic states, and non-adiabatic couplings play an important role in the reaction mechanism. In this work, the effect of non-adiabatic couplings in the H+MgH;→Mg;... A chemical process may involve multiple adiabatic electronic states, and non-adiabatic couplings play an important role in the reaction mechanism. In this work, the effect of non-adiabatic couplings in the H+MgH;→Mg;+H;reaction are studied using the time-dependent wave packet method and trajectory surface hopping method. The calculated results show that the reaction follows a direct abstraction process when the non-adiabatic couplings are neglected. However, when non-adiabatic couplings are included in the calculations, a longlived excited state complex(MgH_(2)+)*can be formed during the reaction. These direct and complex-forming reaction pathways are revealed by trajectory surface hopping calculations.The non-adiabatic couplings induced complex-forming mechanism not only increases the reactivity but also has significant effect on the product vibrational state distribution. 展开更多
关键词 Quantum dynamics Non-adiabaitc reaction Wave packet method
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Dynamics and Manipulation for Gap Solitons in Bose-Einstein Condensates under Optical Lattice and Harmonic Potentials
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作者 宗丰德 黎菁 宋昌盛 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第8期273-280,共8页
By means of an extended variational approach,we study dynamics for gap solitons in a repulsive interactionBose-Einstein condensate under both a harmonic and an optical lattice confinement.The simplified analytic theor... By means of an extended variational approach,we study dynamics for gap solitons in a repulsive interactionBose-Einstein condensate under both a harmonic and an optical lattice confinement.The simplified analytic theorygives the critical strength ratio of harmonic to optical lattice necessary to support multiple stable lattice sites for thecondensate.Moreover,we use numerical experiments to guide and manipulate the gap solitons to an arbitrary positionvia a time-dependent potential.All predictions of the extended variational approach are reasonably close to results ofthe simulations.In particular,the variational model helps capture the composition relationship between the variationsof chirp and amplitude. 展开更多
关键词 Bose-Einstein condensate Gross-Pitaevskii equations extended variational approach gap soli-tons MANIPULATION
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Study on Excess Thermodynamic Parameters and Theoretical Estimation of Ultrasonic Velocity Using Scaled Particle Theory in Binary Liquid Mixtures of 2-Methyl-2-propanol and Nitriles at Different Temperatures 被引量:2
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作者 K. Rajagopal S. Chenthilnath 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第5期804-816,共13页
Density, ρ, ultrasonic speed, u, and viscosity, η, of binary mixtures of 2-methyl-2-propanol (2M2P) with acetonitrile (AN), propionitrile (PN) and butyronitrile (BN) including those of pure liquids are measured over... Density, ρ, ultrasonic speed, u, and viscosity, η, of binary mixtures of 2-methyl-2-propanol (2M2P) with acetonitrile (AN), propionitrile (PN) and butyronitrile (BN) including those of pure liquids are measured over the entire composition range at temperatures 298.15, 303.15 and 308.15 K. From these experimental data, the excess available volume, E a V , excess free volume, E f V , excess isothermal compressibility, E T β , excess thermal expansion coefficient, E α , and excess internal pressure, E i π , are calculated. The variation of these properties with composition and temperature are discussed in terms of molecular interactions between unlike molecules of the mixtures. It is found that the values of E a V , E f V , E T β and E α are positive and those of E i π are negative for all the mixtures at each temperature studied, indicating the presence of weak interactions between 2M2P and AN/PN/BN molecules. The variations of E a V , E f V , E T β , E α and E i π values with composition indicate that the interactions in these mixtures follow the order: AN<PN<BN, i.e., the 2M2P-nitrile interaction decreases with the increase of alkyl chain length in these nitrile molecules. In addition, the theoretical ultrasonic velocity is calculated using the scaled particle theory and compared with the experimental values. 展开更多
关键词 2-methyl-2-propanol homologous nitriles excess properties molecular interactions scaled particle theory
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New Exact Solutions to NLS Equation and Coupled NLS Equations
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作者 FUZun-Tao LIUShi-Da LIUShi-Kuo 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第2期189-194,共6页
A transformation is introduced on the basis of the projective Riccati equations, and it is applied as an intermediate in expansion method to solve nonlinear Schrǒdinger (NLS) equation and coupled NLS equations. Manyk... A transformation is introduced on the basis of the projective Riccati equations, and it is applied as an intermediate in expansion method to solve nonlinear Schrǒdinger (NLS) equation and coupled NLS equations. Manykinds of envelope travelling wave solutions including envelope solitary wave solution are obtained, in which some arefound for the first time. 展开更多
关键词 projective Riccati equations NLS equation envelope travelling wave solution envelope solitary wave solution
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