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Theoretical studies on Lewis acidity scale and bonding character of boron trihalides BX_3(X=F, Cl, Br, I) by DV-X_α quantum chemical approach

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Chinese Journal of Chemistry 1997年第1期15卷 17-20页

作者： CAI, Zheng-Ting LI, Ci-Rant ZHANG, Rui-Qin DENG, Cong-HaoInstitute of Theoretical Chemstry, department of Chemistry, department of {2. shandong university, jinan, shandong 2.0100, china Institute of Theoretical Chemistry Jinan Shandong 250100 China department of Chemistry shandong {2. Jinan Shandong 250100 China department of physics {2. university Jinan Shandong 250100 China

The Lewis acidity scale of boron trihalides BX3 (X=F, Cl, Br, I) and character of the boron-halogen bonds have been studied by means of DV-Xa approach. Present results show that the acid strength of boron trihalides i... 详细信息

关键词： Lewis acidity scale boron trihalides valence of boron DV-Xα quantum chemical approach

Image interpretation of weak-coupling N-mer adsorbate's STM system

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Chinese Science Bulletin 1997年第5期42卷 371-374页

作者： HUANG Xintang, Ql Shouren, LI Xinjiao and LI Yongping1 department of physics, Central{2. normal university, Wuhan 430070,{2. department of Solid State Electronics, Huazhong university of Science and Technology, Wuhan 430074,{2. 2. department of physics, university of Science and Technology of{2., Hefei 2.002.,{2. department of physics Central China Normal University Wuhan China department of Solid State Electronics Huazhong University of Science and Techndogy Wuhan China department of physics University of Science and Technology of China Hefei China

Up to now, there have been many indistinctive points in the image interpretation of scanning tunnelhng microscopy (STM) system, and the problems have attracted almost all STM scientists’ attention. In 1992. Kenkre proposed the new programme which describes the behaviour of the electrons moving in the STM tunnelling by the method of exciton dynamics, and the programme not only breaks through the restrictions of Tersoff-Hamann theory, but also can be applied conveniently to discussing the effects of the tip structure, adsorbate structure, substrate structure, temperature, tunneling voltage, and the degree of coherence of elec-

关键词： weak-coupling N-mer adsorbates STM image interpretation exciton dynamics method.

Spectral anomalies and spectral switches of partially coherent and polychromatic light diffracted at an aperture

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Science china(physics,Mechanics & Astronomy) 2004年第1期47卷 24-35页

作者： Lü Baida1, 3 & PAN Liuzhan1, 2.1. Institute of Laser physics and Chemistry, Sichuan university, Chengdu 610064,{2. 2. department of physics, Luoyang normal College, Luoyang 47102.,{2. 3. State Key Laboratory of Laser Technology, Huazhong university of Science and Technology, Wuhan 430074,{2. Correspondence should be addressed to L Baida (email: badalu@***) Received July 10, 2.03 Institute of Laser physics and Chemistry Sichuan University Chengdu China State Key Laboratory of Laser Technology Huazhong University of Science and Technology Wuhan China department of physics Luoyang Normal College Luoyang China

Based on the propagation theory of partially coherent light in the space-frequency domain, the anomalous spectral behavior and spectral switches in the far field of partially coherent and polychromatic light diffracted at an aperture are studied. It is shown that, as compared with spatially fully coherent and polychromatic light whose spectral anomalies are induced only by aperture diffraction, the spectral anomalies and spectral switches of partially coherent and polychromatic light depend on the aperture diffraction, spatial correlationβ and bandwidth of the original spectrum. Detailed numerical calculations are made to illustrate the behavior of spectral switches of partially coherent and polychromatic light, and the results for spatially fully coherent and polychromatic light are treated as a special case ofβ=1 and included in our theory.

关键词： spectral anomaly spectral switch partially coherent and polychromatic light far field aperture diffraction

Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2.molecule

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Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2. SUN Weiguo1, HOU Shilin3 & FENG Hao4 1. Institute of physics, College of Chemical Engineering, Sichuan university, Chengdu 610065,{2. 2. Institute of Theoretical physics, Xihua normal university, Nanchong 637002.{2. 3. department of physics,{2. Oceanography university, Qingdao 2.6003,{2. 4. College of physics, Sichuan university, Chengdu 610065,{2. Institute of physics College of Chemical Engineering Sichuan University Chengdu China Institute of Theoretical physics Xihua Normal University Nanchong China department of physics China Oceanography University Qingdao China College of physics Sichuan University Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2.molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

Constraints of f(R) gravity in Palatini approach with observational Hubble data

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Science china(physics,Mechanics & Astronomy) 2011年第8期54卷 1378-1383页

作者： ZHAI ZhongXu & LIU WenBiao department of physics, Institute of Theoretical physics, Beijing normal university, Beijing 100875, china department of physics Institute of Theoretical Physics Beijing Normal University Beijing China

We use the newly released observational H(z) data (OHD), the Cosmic Microwave Background (CMB) shift parameter, and the Baryon Acoustic Oscillation (BAO) measurements data to constrain cosmological parameters of f(R) gravity in Palatini formalism in which the f(R) form is defined as f(R) = R β/Rn. Under the assumption of a spatially flat FRW universe, we get the best fitting results of the free parameters (Ωm0, n). In the calculation, we marginalize the likelihood function over H0 by integrating the probability density P ∝ e-χ2.2.to obtain the best fitting results and the confidence regions in the Ωm0-n plane. The constraints results of (Ωm0, n) = (0.33, 0.41) by OHD only and (Ωm0, n) = (0.2., 0.08) by the combination of OHD+CMB+BAO both indicate that the universe goes through three last phases, i.e., radiation dominated, matter-dominated, and late time accelerated expansion without introduction of dark energy.

关键词： f(R) gravity OHD CMB BAO accelerating expansion dark energy

Optimal reactions for the synthesis of superheavy nucleus ^(2.0)Hs

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Science china(physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3 & BAO Jingdong1,2.1. Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing normal university, Beijing 100875,{2. 2. physics department, Beijing normal university, Beijing 100875,{2. 3.{2. Institute of Atomic Energy, Beijing 102.13,{2. Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing China china Institute of Atomic Energy Beijing China physics department Beijing Normal University Beijing China

The superheavy nucleus 2.0Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 2.8Cm(2.Mg,4n)2.0Hs, 2.4Pu(30Si,4n)2.0Hs, 2.8U(36S,4n)2.0Hs and 2.6Ra(48Ca,4n)2.0Hs using a two-parameter Smoluchowski equation. It is found from our results that 2.6Ra(48Ca,4n)2.0Hs and 2.8U(36S,4n)2.0Hs are two optimal reactions for the synthesis of the superheavy nucleus 2.0Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

The Research of Scattering Cross-Section and Energy-Extraction in FEL

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Chinese Journal of Lasers 1995年第1期B4卷 25-29页

作者： ZHU Jiaqing (department of physics,Central{2. normal university,Wuhan,430070,china) Central china normal Univ Wuhan China

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关键词： free-electron laser scattering cross-section

Codimension 3 nonresonant bifurcations of homoclinic orbits with two inclination flips

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Science china Mathematics 2005年第2期48卷 248-260页

作者： SHUI Shuliang & ZHU Deming College of Mathematics and physics, Zhejiang normal {2., Jinhua 32.004, china department of Mathematics, East china normal {2., Shanghai 2.0062. china College of Mathematics and physics Zhejiang Normal University Jinhua China department of Mathematics East China Normal University Shanghai China

Homoclinic bifurcations in four-dimensional vector fields are investigated by setting up a local coordinate near a homoclinic orbit. This homoclinic orbit is principal but its stable and unstable foliations take inclination flip. The existence, nonexistence, and uniqueness of the 1-homoclinic orbit and 1-periodic orbit are studied. The existence of the two-fold 1-periodic orbit and three-fold 1 -periodic orbit are also obtained. It is indicated that the number of periodic orbits bifurcated from this kind of homoclinic orbits depends heavily on the strength of the inclination flip.

关键词： bifurcation, homoclinic orbit, non-resonance, inclination flip, 1-periodic orbit.

Output Rate of Atomic Four-Wave Mixing in Two-Component Bose-Einstein Condensate

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Communications in Theoretical physics 2004年第5期41卷 695-698页

作者： LI Jia-Hua~1 LI Wei-Bing~1 PENG Ju-Cun~2.1 department of physics,Huazhong {2. of Science and Technology,Wuhan 430074,china2.department of physics,Xiaogan normal {2.,Xiaogan 432.00,china department of physics Huazhong University of Science and Technology Wuhan 430074 China department of physics Xiaogan Normal University Xiaogan 432100 China

In this letter,following the proposal of Heurich et al.[***.A63(2.01)033605],we analyze anddiscuss output rate of atomic four-wave mixing in the two-component Bose-Einstein condensate under the condition ofthe steady *** results show that the magnitude of the signal beam increases with the increase of the intensityof the probe beam,up to a saturated value,then it decreases as the probe beam *** influence of theinteraction range on the signal beam is also *** particular,it is worth while pointing out that in contrast tothe previous solutions,our obtained analytical solutions are of very simple and explicit forms,which open the door forfurther investigating the related physical mechanisms.

关键词： atomic four-wave mixing steady state Bose-Einstein condensate