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Relationship Between Differential Interference Angle and Parameter of Experiment in Molecular Beam

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Communications in Theoretical Physics 2006年第2X期46卷 294-296页

作者： li yong-qing li Jian MA Feng-Cai Department of Physics Liaoning University Shenyang 110036 China

Collisional quantum interference （CQI） was observed in the intramolecular rotational energy transfer in the experiment of the static cell, and the integral interference angles were measured. To observe more precise information, the experiment in the molecular beam should be taken,from which the relationship between the differential interference angle and the scattering angle can be obtained. In this paper, the theoretical model of CQI is described in an atom-diatom system in the condition of the molecular beam, based on the first-Born approximation of time-dependent perturbation theory, taking into accounts the long-range interaction potential. The method of observing and measuring correctly the differential interference angle is presented. The changing tendency of the differential interference angle with the impact parameter and relative velocity is discussed. The changing tendencies of the differential interference angle with the parameter of experiment in the molecular beam, including the impact parameter and the velocity are discussed. This theoretical model is important to understand or perform the experiment in the molecular beam.

关键词： differential interference angle quantum interference rotational energy transfer

Small World Properties Generated by a New Algorithm Under Same Degree of All Nodes

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Communications in Theoretical Physics 2006年第5期45卷 950-954页

作者： li yong FANG Jin-qing liU Qiang liANG yong China Institute of Atomic Energy P.O. Box 275-81 Beijing 102413 China

Based on the model of the same degree of all nodes we proposed before, a new algorithm, the so-called “spread all over vertices” （SAV） algorithm, is proposed for generating small-world properties from a regular ring lattices. During randomly rewiring connections the SAV is used to keep the unchanged number of links. Comparing the SAV algorithm with the Watts-Strogatz model and the “spread all over boundaries” algorithm, three methods can have the same topological properties of the small world networks. These results offer diverse formation of small world networks. It is helpful to the research of some applications for dynamics of mutual oscillator inside nodes and interacting automata associated with networks.

关键词： small world network the same degree of all nodes in the network “spread all over vertices”algorithm average shortest path length average clustering coefficient

Two new glycosides from the seeds of Cassia obtusifolia

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Chinese Chemical Letters 2009年第9期20卷 1097-1099页

作者： Cun Zhang Gui liu li yong qing Xiao li li Zhen Pang Institute of Traditional Chinese Materia Madica Chinese Academy of Chinese Medical Sciences Beijing 100700 China

Two new glycosides, nor-rubrofusadn-6-O-β-D-（6＇-O-acetyl）glucopyranoside （1） and 1-desmethylaurantio-obtusin-2-O-β-D- glucopyranoside （2） were isolated from the seeds of Cassia obtusifolia and their structures were established by chemical and spectral evidences. 2009 yong qing Xiao. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Cassia obtusifolia Nor-rubrofusarin-6-O-β-D-(6'-O-acetyl)glucopyranoside 1-Desmethylaurantio-obtusin-2-O-β-D-glucopyranoside

Excited State Properties of Fluorine-Substituted Hexabenzocoronene： A Quantum-Chemical Characterization

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Communications in Theoretical Physics 2006年第2X期46卷 229-232页

作者： li Yuan-Zuo SUN Yu li yong-qing MA Feng-Cai Department of Physics Liaoning University Shenyang 110036 China

The first fluorine-substituted hexabenzocoronene has been synthesized and its electronic structure and optical properties have been reported [Q. Zhang, et al., Org. Lett. 7 （2005） 5019]. In this letter, the electronic structure and excited state properties of the fluorine-substituted hexabenzocoronene are studied with quantum chemistry method as well as the transition and the charge difference densities. The transition densities show the orientations and strength of the dipole moments and the charge difference densities reveal the orientation and results of the intramolecular charge transfer. The calculated transition energies and oscillator strengths are consistent with the experimental data, and the theoretical results of transition and charge difference densities are valuable to understanding the excited state properties of the fluorine-substituted hexabenzocoronene.

关键词： intramolecular charge transfer fluorine-substituted hexabenzocoronene transition densities charge difference densities

Collisional Quantum Interference on Rotational Energy Transfer： Relation Between Integral Interference Angle and Rotational Quantum Number in Na2（A^1∑u^＋,ν=8～b^3∏0u,ν=14）-Na System

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Communications in Theoretical Physics 2006年第1X期46卷 123-129页

作者： WANG Wei-li SONG Peng li yong-qing MIAO Gang MA Feng-Cai School of Science Liaoning Technical University Fuxin 123000 China Dalian Institute of Chemical Physics the Chinese Academy of Sciences Dalian 16023 China Department of Physics Liaoning University Shenyang 110036 China

Collisional quantum interference （CQI） on rotational energy transfer was observed in Na2（A^1∑u^＋,ν=8～b^3∏0u,ν=14） system in collision with Na [Chem. Phys. Lett. 318 （2000） 107], and the degree of the interference was measured. The integral interference angle was obtaJned through theoretical calculation. We will research the factors that have effect on collisional quantum interference on rotational energy transfer in Na2（A^1∑u^＋,ν=8～b^3∏0u,ν=14）-Na system. Basing on the time-dependent first order Born approximation, and taking into account the anlsotroplc Lennard Jones interaction potentials and ＂straight-line＂ trajectory approximation, we obtain the factors that have effect on CQI in Na2-Na system, and obtain the relation between the integral interference angle and rotational quantum number.

关键词： rotational energy transfer interference angle rotational quantum number

Further Study of A-Related Quantum Interference of H-State Diatomic on Collision-Induced Rotational Energy Transfer

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Communications in Theoretical Physics 2005年第2X期44卷 347-352页

作者： li yong-qing SONG Peng CHEN Yue-Hui WANG Wei-li MA Feng-Cai Department of Physics Liaoning University Shenyang 110036 China

In our previous theoretical studies [Meng-Tao Sun, yong-qing Lee, and Feng-Cai Ma, Chem. ***. 371 （2003） 342], we have reported the quantum interference on collision-induced rotational energy transfer on CO （A ^1 Π,v = 3） with inert gases, which originates from the difference between the two A-related collision potential energy surfaces. The interference angle, which measures the degree of coherence, is presented in this paper. Based on the time-dependent first order Born approximation, taking into account the anisotropic Lennard-Jones interaction potentials, the relation of the interference angle with the factors, including experimental temperature, partner, and rotational quantum number, are obtained. The changing tendencies with them are discussed. This theoretical model is important to understanding and performing this kind of experiment.

关键词： quantum interference rotational energy transfer interference angle

Bilateral bidirectional superior cavopulmonary shunt is more beneficial in medium and long term clinical outcomes than unilateral shunt

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Chinese Medical Journal 2009年第2期122卷 129-135页

作者： XU Yao-qiang liU Ying-long LU Xiao-dong li yong-qing YU Cun-tao Pediatric Cardiac Center Cardiovascular Institute and Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China

Background The present study was aimed to compare the effects of bilateral and unilateral bidirectional superior cavopulmonary shunt （b-BDG and u-BDG） on pulmonary artery growth and clinical outcomes. Methods The 51 subjects enrolled in this study were divided into two groups： those receiving b-BDG （n=21） and those receiving u-BDG （n=30）. Clinical records were reviewed retrospectively at a mean of 43.3 months after BDG procedures. Chi square and t-tests were performed to analyze the data. Results Left and right pulmonary artery diameters increased 27%-37% in both groups. The pulmonary artery index increased 37.2% after b-BDG and 27.0% after u-BDG, b-BDG patients experienced a significant decrease in mean hemoglobin concentration and hematocrit value, and a correlated change in postoperative diameter of left pulmonary artery （LPA） and pulmonary artery index （y=0.2719, x=-1.8278; R=0.564, P=-0.008）. The change ratio of hemoglobin and postoperative LPA were also correlated in b-BDG patients （y= -0.0522x ＋ 0.3539; R=-0.479, P=-0.028）. Only one b-BDG patient versus twelve u-BDG patients needed total cavopulmonary connections 31.8 months after BDG surgery （P=-0.0074）. Moreover, only one （4.8%） b-BDG patient but eight u-BDG patients （26.7%） developed pulmonary arteriovenous malformations. Conclusions b-BDG increases bilateral pulmonary blood flow and promotes growth of bilateral pulmonary arteries, with preferable physiological outcomes to u-BDG. Results may imply that subsequent Fontan repair may not always be needed. Chin Med J 2009; 122（2）： 129-135

关键词： cavopulmonary shunts congenital heart defects cyanosis heart bypass, right pulmonary artery, hypoplasia

A new phenanthraquinone from the roots of Peucedanum praeruptorum

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Chinese Chemical Letters 2010年第7期21卷 816-817页

作者： Cun Zhang li li yong qing Xiao Wen li Xiao Jie Yin Guo Fang Tian Dong Dong Chen Yun Wang Institute of Chinese Materia Madica China Academy of Traditional Chinese MedicineBeijing 100700China

A new compound,9,10-dihydrophenanthrinic acid,9,10-dione-3,4-methylenedioxy-8-methoxy（1） was isolated from the roots of Peucedanum praeruptorum Dunn on the basis of spectral evidences.

关键词： Peucedanum praeruptorum 9 10-Phenanthraquinone 9 10-Dihydrophenanthrinic acid 9 10-Dione-3 4-methylenedioxy-8-methoxy

Influence of pressure disturbance wave on dynamic response characteristics of liquid film seal for multiphase pump

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Petroleum Science 2024年第3期21卷 2048-2065页

作者： qing-Ping li Jin-Ya Zhang Jia-Xiang Zhang yong-Xue Zhang CNOOC Research Institute Company limited Beijing100028China State Key Laboratory of Natural Gas Hydrate Beijing100028China College of Mechanical and Transportation Engineering China University of PetroleumBeijing2249China

Slug flow or high GVF(Gas Volume Fraction)conditions can cause pressure disturbance waves and alternating loads at the boundary of mechanical seals for multiphase pumps,endangering the safety of multiphase pump *** mechanical seal model is simplified by using periodic boundary conditions and numerical calculations are carried out based on the Zwart-Gerber-Belamri cavitation ***(User Define Function)programs such as structural dynamics equations,alternating load equations,and pressure disturbance equations are embedded in numerical calculations,and the dynamic response characteristics of mechanical seal are studied using layered dynamic mesh *** results show that when the pressure disturbance occurs at the inlet,as the amplitude and period of the disturbance increase,the film thickness gradually *** the fundamental reason for the hysteresis of the film thickness change is that the pressure in the high-pressure area cannot be restored in a timely *** maximum value of leakage and the minimum value of axial velocity are independent of the disturbance period and determined by the disturbance *** mutual interference between enhanced waves does not have a significant impact on the film thickness,while the front wave in the attenuated wave has a promoting effect on the subsequent film thickness changes,and the fluctuation of the liquid film cavitation rate and axial velocity under the attenuated wave condition deviates from the initial *** with pressure disturbance conditions,alternating load conditions have a more significant impact on film thickness and *** actual operation,it is necessary to avoid alternating load conditions in multiphase pump mechanical seals.

关键词： Multiphase pump liquid film seal Pressure disturbance wave Dynamic response characteristics