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想象、叙事与文化的再发现——读《表象的叙述——新社会文化史》 被引量:1
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作者 沈洁 《学海》 CSSCI 北大核心 2006年第3期189-195,共7页
20世纪80年代以来,社会史研究无论在历史认识上还是在叙述范式上都发生了新的变化。在后现代主义以及语言学、人类学等学科的影响下,历史研究实现了“语言转向”和“文化转向”的范式转换。通过对文化事象的再发现与叙事方式的革新,历... 20世纪80年代以来,社会史研究无论在历史认识上还是在叙述范式上都发生了新的变化。在后现代主义以及语言学、人类学等学科的影响下,历史研究实现了“语言转向”和“文化转向”的范式转换。通过对文化事象的再发现与叙事方式的革新,历史学不再被当作单纯的事件排列和描述,而是在追述文化事象、文化情境的基础上实现对知识的创造。新社会文化史的兴起对于中国史学极具启发意义,而如何在中国情境中有效地内化并展开这一范式转换,同样显得十分紧迫。 展开更多
关键词 表象 叙述 《表象的叙述——新社会文化史》 文化 书评 社会史研究 叙述范式 后现代主义
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LOCALIZATION OF OBJECT (SPINE) IN MEDICAL IMAGE USING ACTIVE SHAPE MODELS 被引量:2
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作者 徐涛 蔡宇新 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期211-217,共7页
Active shape models (ASM), consisting of a shape model and a local gray-level appearance model, can be used to locate the objects in images. In original ASM scheme, the model of object′s gray-level variations is base... Active shape models (ASM), consisting of a shape model and a local gray-level appearance model, can be used to locate the objects in images. In original ASM scheme, the model of object′s gray-level variations is based on the assumption of one-dimensional sampling and searching method. In this work a new way to model the gray-level appearance of the objects is explored, using a two-dimensional sampling and searching technique in a rectangular area around each landmark of object shape. The ASM based on this improvement is compared with the original ASM on an identical medical image set for task of spine localization. Experiments demonstrate that the method produces significantly fast, effective, accurate results for spine localization in medical images. 展开更多
关键词 object localization active shape models (ASM) gray-level appearance model principal component analysis SPINE
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EXPERIMENTAL STUDY ON DARCY′S LAW IN HELE-SHAW CELLS 被引量:1
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作者 孙建红 许金造 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第2期134-139,共6页
The basic physics of unsteady Hele-Shaw flow at high Reynolds numbers is mainly studied by an experimental measurement. In order to confirm the Darcy′s law in Hele-Shaw cell, since there is an analogy between flow in... The basic physics of unsteady Hele-Shaw flow at high Reynolds numbers is mainly studied by an experimental measurement. In order to confirm the Darcy′s law in Hele-Shaw cell, since there is an analogy between flow in cells and that in porous media, progressive water waves are utilized to build an unsteady flow in a Hele-Shaw cell, and which complex wave number is measured by a wave height gauge. Meanwhile, theoretical analyses are used to compare with experimental data. Result shows Darcy′s Law is not exactly correct for unsteady Hele-Shaw flows, and it is expected to conduct a modified Darcy′s Law. 展开更多
关键词 Hele-Shaw cell surface water wave Darcy′s law
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Comparison and Analysis between Two Types of Sounding Data of China
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作者 陈哲 臧海佳 《Agricultural Science & Technology》 CAS 2009年第6期175-177,共3页
The upper air weather forecast data used in current business and research and digital data of the recently finished upper air meteorological monthly report were comparatively analyzed in complete data and quality cond... The upper air weather forecast data used in current business and research and digital data of the recently finished upper air meteorological monthly report were comparatively analyzed in complete data and quality condition of data, and sounding curve change caused by the difference of complete data was also compared, which evaluated advantages and disadvantages of two types of data. 展开更多
关键词 SOUNDING Coded messages for upper-level data Monthly tables of sounding
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Exploration of regional surface average heat flow from meteorological and geothermal series 被引量:1
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作者 刘迁迁 魏东平 +1 位作者 孙振添 张晓惠 《Applied Geophysics》 SCIE CSCD 2013年第4期496-505,513,共11页
We attempt to compute the Surface Average Heat Flow (SAHF) from long-term temperature observations of one hundred seventy-seven observational points at the depths of 0.8, 1.6, and 3.2 m, which were relatively evenly... We attempt to compute the Surface Average Heat Flow (SAHF) from long-term temperature observations of one hundred seventy-seven observational points at the depths of 0.8, 1.6, and 3.2 m, which were relatively evenly distributed in China's Mainland. We first employ Fourier transformation to remove the influence of atmospheric temperature variations from the observation series, which are classified into the type of the steady-state temperature monotonously increasing with depth (type I) and other three types. Then we compare our results obtained from the data of type I, of which the values are thought to equal to those of the mean borehole heat flow, with those obtained from traditional heat flow observations mainly distributed in North China Craton. In computations of the SAHF at the observation stations, we deduce the thermal diffusivity and volumetric specific heat of the soil by employing harmonic solutions of the heat conduction equation for the same moisture group as the first step, and then we determine the SAHF using Fourier's law. Our results indicate that the SAHF derived from shallow earth geothermal data can reflect the heat flow field to a large extent. 展开更多
关键词 Meteorological and geothermal series Surface average heat flow Heat flow Soil thermal diffusivity Soil volumetric specific heat
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REPRESENTATION PROPERTIES OF ABSTRACT DEFAULT REASONING FRAMEWORKS
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作者 曹子宁 毛宇光 石纯一 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第3期214-221,共8页
presented The conceptions of abstract default reasoning frameworks (ADRFs) and D-consequence relations are Based on representation properties of D-consequence relations, it proves that any cumulative nonmonotonic co... presented The conceptions of abstract default reasoning frameworks (ADRFs) and D-consequence relations are Based on representation properties of D-consequence relations, it proves that any cumulative nonmonotonic consequence relation with the connective-free form can be represented by ADRFs. 展开更多
关键词 abstract default reasoning framework representation property nonmonotonie reasoning
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Effect of Quantum Fluctuation on Two-Dimensional Spatially Anisotropic Heisenberg Antiferromagnet with Integer Spin 被引量:1
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作者 JI An-Chun TIAN Guang-Shan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6期1137-1146,共10页
In the present paper, we calculate the Gaussian correction to the critical value J^c⊥ caused by quantum spin fluctuation in a two-dimensional spatially anisotropic Heisenberg antiferromagnet with integer spin S. Prev... In the present paper, we calculate the Gaussian correction to the critical value J^c⊥ caused by quantum spin fluctuation in a two-dimensional spatially anisotropic Heisenberg antiferromagnet with integer spin S. Previously, some authors computed this quantity by the mean-field theory based on the Sehwinger boson representation of spin operators. However, for S = 1, their result is much less than the one derived by numerical calculations. By taking the effect of quantum spin fluctuation into consideration, we are able to produce a greatly improved result. 展开更多
关键词 spatially anisotropic Heisenberg model functional integration Schwinger boson representation
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ADSORPTION OF PHENOL AND Pb^(2+) FROM AQUEOUS SOLUTIONS BY A NEW DI-FUNCTION ADSORBENT WITH SULFHYDRYL GROUPS 被引量:3
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作者 WANG Jinnan LI Aimin +1 位作者 ZHANG Bo ZHANG Quanxing 《Chinese Journal of Reactive Polymers》 2007年第1期46-54,共9页
A new di-function adsorbent (JN-3) was prepared by sulfhydryl modified. Comparing with Amberlite XAD-4 and NDA-150, the equilibrium adsorption for phenol on the JN-3 from aqueous solutions was tested, perfect adsorpti... A new di-function adsorbent (JN-3) was prepared by sulfhydryl modified. Comparing with Amberlite XAD-4 and NDA-150, the equilibrium adsorption for phenol on the JN-3 from aqueous solutions was tested, perfect adsorption capacity was shown. Pb2+ can be also removed by JN-3 because of the chelate interaction between sulfhydryl groups and metal ions. This adsorbent could be used in removal of combine pollutants such as phenolic compounds and heavy metal ions from waste streams. 展开更多
关键词 SULFHYDRYL Di-function resin PHENOL Pb2^+ Adsorption.
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Numerical Convergence of the Sinc Discrete Variable Representation for Solving Molecular Vibrational States with a Conical Intersection in Adiabatic Representation
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作者 Hai-mei Shi Guang-hai Guo Zhi-gang Sun 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2019年第3期333-342,I0001-I0002,共12页
Within the Born-Oppenheimer(BO)approximation,nuclear motions of a molecule are often envisioned to occur on an adiabatic potential energy surface(PES).However,this single PES picture should be reconsidered if a conica... Within the Born-Oppenheimer(BO)approximation,nuclear motions of a molecule are often envisioned to occur on an adiabatic potential energy surface(PES).However,this single PES picture should be reconsidered if a conical intersection(CI)is present,although the energy is well below the CI.The presence of the CI results in two additional terms in the nuclear Hamiltonian in the adiabatic presentation,i.e.,the diagonal BO correction(DBOC)and the geometric phase(GP),which are divergent at the CI.At the same time,there are cusps in the adiabatic PESs.Thus usually it is regarded that there is numerical difficulty in a quantum dynamics calculation for treating CI in the adiabatic representation.A popular numerical method in nuclear quantum dynamics calculations is the Sinc discrete variable representation(DVR)method.We examine the numerical accuracy of the Sinc DVR method for solving the Schrodinger equation of a two dimensional model of two electronic states with a CI in both the adiabatic and diabatic representation.The results suggest that the Sinc DVR method is capable of giving reliable results in the adiabatic representation with usual density of the grid points,without special treatment of the divergence of the DBOC and the GP.The numerical uncertainty is not worse than that after the introduction of an arbitrary vector potential for accounting the GP,whose accurate form usually is not easy to obtain. 展开更多
关键词 Discrete variable representation Conical intersection Adiabatic and diabatic representaton Geometric phase
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An Observational Study of Typhoon Imbudo in 2003 被引量:1
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作者 LI Qingqing FU Gang +2 位作者 GUO Jingtian YANG Yuqiang DUAN Yihong 《Journal of Ocean University of China》 SCIE CAS 2005年第4期391-397,共7页
Typhoon Imbudo was a super-typhoon over the northwestern Pacific in 2003. It caused tremendous damage when it made landfalls in the Philippines and China. This paper documents observational analyses of Typhoon Imbudo ... Typhoon Imbudo was a super-typhoon over the northwestern Pacific in 2003. It caused tremendous damage when it made landfalls in the Philippines and China. This paper documents observational analyses of Typhoon Imbudo during its landfall in China. All available observations are used to study its motion, intensity changes, convection, structure and precipitation. Best-track data indicate that Imbudo moved west-northwestward until 1800 UTC 23 July and then turned northwestward. FNL (final) analysis data show that the motion of Imbudo is dominated by changes of the subtropical high. At Imbudo's mature stage, the minimum sea level pressure dropped to 910 hPa and the maximum sustained winds were as high as 67 m s 1, which is the intensity of a super-typhoon. The surface wind field exhibited asymmetric characteristics. Polar-orbiting satellite imagery also manifested convective asymmetry before Imbudo made landfall in China. Analyzed the vertical wind shear, it is shown that the convection has a downshear-left pattern. All kinds of precipitation data were used to identify the asymmetric characteristic of the rainfall associated with the Imbudo. The maximum rainfalls were located in the southern boundary area between Guangxi and Guangdong. However, the lack of in situ observations limited further analyses of this typhoon. 展开更多
关键词 Typhoon Imbudo surface winds satellite imagery asymmetric convection downshear-left convective pattern asymmetric rainfall
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Complex-Variable Fokker-Planck Equation Solved in Entangled State Representation
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作者 唐绪兵 范洪义 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第6期1049-1052,共4页
We lind that the Fokker-Planck equation in complex variables can be conveniently solved in the context of bipartite entangled state representation and its relationship with SU(2) Lie algebraic generators' new reali... We lind that the Fokker-Planck equation in complex variables can be conveniently solved in the context of bipartite entangled state representation and its relationship with SU(2) Lie algebraic generators' new realization {(1/4)[(Q1 - Q2)^2 + (P1+ P2)^2], (1/4)[(Q1 +Q2)^2+ (P1 - P2)^2], and -(i/2)(Q1P2 + Q2P1)}, the quadratic combination of canonical operators. 展开更多
关键词 Fokker Planck equation entangled state representation SU(2) Lie algebra
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EXPERIMENTAL RESEARCH ON EFFECTS OF INITIAL JOINTS ON SURFACE DISPLACEMENT DUE TO COAL MINING 被引量:4
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作者 谢和平 于广明 +1 位作者 杨伦 周宏伟 《Journal of Coal Science & Engineering(China)》 1999年第1期16-23,共8页
Surface displacement caused by underground coal mining is influenced by many factors such as the depth and thickness of the coal seam and joints in overburben rocks. Extensive efforts have been devoted to the ground s... Surface displacement caused by underground coal mining is influenced by many factors such as the depth and thickness of the coal seam and joints in overburben rocks. Extensive efforts have been devoted to the ground surface displacement. Nevertheless, the joints have not been taken into consideration for a long time. In fact, there exist numerous joints and cracks in rocks.As a result, the joints in overburden rocks have to be taken into account. The joints in rocks can be treated as initial damage theoretically. In this paper, two kinds of physical model, one containing no initial joints and anotber containing some initial joints, are employed to systematically investigate effecs of initial joints on surface subsidence. Moreover, within the framework of damage mechanics, the statistical relationships between the characteristic value for surface displacement and damage variable are obtained. 展开更多
关键词 jointed rocks mining subsidence damage variable
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Some New Properties of Wigner Function Studied in Entangled State Representation
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作者 范洪义 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第8期241-243,共3页
Based on the Wigner operator in the entangled state representation we study some new important propertiesof Wigner function for bipartite entangled systems,such as size of an entangled state,upper bound of Wigner func... Based on the Wigner operator in the entangled state representation we study some new important propertiesof Wigner function for bipartite entangled systems,such as size of an entangled state,upper bound of Wigner functions,etc.These discussions demonstrate the beauty and elegance of the entangled state representation. 展开更多
关键词 Wigner function entangled state representation Wigner operator
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Quantum Mechanical Correspondence of Poisson Integral Formula
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作者 范洪义 姜年权 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第2期217-220,共4页
In this paper we set up quantum mechanical correspondence of the Poisson integral formula.We show that Poisson kernel function existing in the transformation between the continuum entangled state representation and it... In this paper we set up quantum mechanical correspondence of the Poisson integral formula.We show that Poisson kernel function existing in the transformation between the continuum entangled state representation and its induced state,i.e.the number-difference-correlated amplitude entangled state representation. 展开更多
关键词 Poisson integral formula entangled state representation quantum mechanical correspondence
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New Formulation of Weyl Quantization Scheme in Coherent State Representation
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作者 刘堂昆 范洪义 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第1期38-40,共3页
By virtue of the technique of integration within an ordered product of operators we present a new formulation of the Weyl quantization scheme in the coherent state representation, which not only brings convenience for... By virtue of the technique of integration within an ordered product of operators we present a new formulation of the Weyl quantization scheme in the coherent state representation, which not only brings convenience for calculating the Weyl correspondence of normally ordered operators, but also directly leads us to find both the coherent state representation and the Weyl ordering representation of the Wigner operator. 展开更多
关键词 coherent state representation Weyl rule Wigger operator
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Optical Operator Method in Two-Mode Case and Entangled Fresnel Operator's Decomposition
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作者 马善钧 胡利云 范洪义 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第5期907-912,共6页
Based on the entangled Fresnel operator (EFO) proposed in [Commun. Theor. Phys. 46 (2006) 559], the optical operator method studied by the IWOP technique (Ma et al., Commun. Theor. Phys. 49 (2008) 1295) is ext... Based on the entangled Fresnel operator (EFO) proposed in [Commun. Theor. Phys. 46 (2006) 559], the optical operator method studied by the IWOP technique (Ma et al., Commun. Theor. Phys. 49 (2008) 1295) is extended to the two-mode case, which gives the decomposition of the entangled Fresnel operator, corresponding to the decomposition of ray transfer matrix [A, B, C, D]. The EFO can unify those optical operators in two-mode case. Various decompositions of EFO into the exponential canonical operators are obtained. The entangled state representation is useful in the research. 展开更多
关键词 optical operator method entangled Fresnel operator IWOP technique
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Generalized Wigner Operator and Bivariate Normal Distribution in p-q Phase Space
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作者 FAN Hong-Yi WANG Tong-Tong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第12期1299-1302,共4页
We introduce a kind of generalized Wigner operator,whose normally ordered form can lead to the bivariatenormal distribution in p-q phase space.While this bivariate normal distribution corresponds to the pure vacuum st... We introduce a kind of generalized Wigner operator,whose normally ordered form can lead to the bivariatenormal distribution in p-q phase space.While this bivariate normal distribution corresponds to the pure vacuum state inthe generalized Wigner function phase space,it corresponds to a mixed state in the usual Wigner function phase space. 展开更多
关键词 bivariate normal distribution generalized Wigner operator
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Mapped Finite Element Discrete Variable Representation
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作者 De-quan Yu Shu-lin Cong +1 位作者 Dong H. Zhang Zhi-gang Sun 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第6期755-764,I0005,共11页
Efficient numerical solver for the SchrSdinger equation is very important in physics and chemistry. The finite element discrete variable representation (FE-DVR) was first proposed by Rescigno and Mc-Curdy [Phys. Rev... Efficient numerical solver for the SchrSdinger equation is very important in physics and chemistry. The finite element discrete variable representation (FE-DVR) was first proposed by Rescigno and Mc-Curdy [Phys. Rev. A 62, 032706 (2000)] for solving quantum-mechanical scattering problems. In this work, an FE-DVR method in a mapped coordinate was proposed to improve the efficiency of the original FE-DVR method. For numerical demonstration, the proposed approach is applied for solving the electronic eigenfunctions and eigenvalues of the hydrogen atom and vibrational states of the electronic state 3E+ of the Cs2 molecule which has long-range interaction potential. The numerical results indicate that the numerical efficiency of the original FE-DVR has been improved much using our proposed mapped coordinate scheme. 展开更多
关键词 Discrete variable representation Mapped Fourier method Ultra-cold atomic photoassociation Schrodinger equation solver Singularity of Coulomb potential
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Contemporary Chinese Calligraphy Between Tradition and Innovation 被引量:2
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作者 Adriana Iezzi 《Journal of Literature and Art Studies》 2013年第3期158-179,共22页
Since the mid-1980s Chinese calligraphy art has undergone a radical change and has opened itself to experimentation. A vivid debate on CCC (Contemporary Chinese Calligraphy) (Zhongguo xiandai shufa) is involving a... Since the mid-1980s Chinese calligraphy art has undergone a radical change and has opened itself to experimentation. A vivid debate on CCC (Contemporary Chinese Calligraphy) (Zhongguo xiandai shufa) is involving art critics in China nowadays. WANG Dongling and the modernists think that, despite many changes and influences, we can still refer to the traditional calligraphic lexicon to describe the calligraphic production of contemporary Chinese art. They still remain deeply rooted in the signified system of Chinese writing, even if they break with the strict rules of Chinese classical aesthetic (contamination of Western elements and focus on the stylistic exploration). WANG Nanming and the Avant-garde think that "contemporary calligraphy is not calligraphy yet": It is "anti-calligraphy", annihilates Chinese tradition, rejects the use of legible characters, experiments with new languages and new media within the idiom of international contemporary art. The result is the creation of works of art that could be assimilated to Abstract art, Abstract expressionism, Conceptual art, Performance art, Contemporary dance, Multimedia art, and even Street art. This paper aims at showing how still valid and extremely productive are both these two theoretical and creative/practical approaches to Chinese calligraphy in China nowadays. They turned the art of calligraphy into a medium for global comprehension and communication. 展开更多
关键词 CCC (Contemporary Chinese Calligraphy) MODERNISM AVANT-GARDE WANG Dongling WANG Nanming
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Theoretical Study on the Rotational Spectra of Ar-D232S Complex
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作者 Jin-ping Lei Yan-zi Zhou Dai-qian Xie 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第6期656-660,I0003,共6页
We report a theoretical study on the rotational spectra of Ar-D232S. The intermolecular po- tential energy surface was transformed from our latest ab initio three-dimensional potential of Ar-H232S. The rotational ener... We report a theoretical study on the rotational spectra of Ar-D232S. The intermolecular po- tential energy surface was transformed from our latest ab initio three-dimensional potential of Ar-H232S. The rotational energy levels and wavefunctions of the complex were calcu- lated by using the radial discrete variable representation/angular finite basis representation method and the Lanczos algorithm. The calculated rotational transition frequencies and structural parameters were found to be in good agreement with the available experimental values. 展开更多
关键词 Rotational spectrum Van der Waals complex Molecular structure
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