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lie Algebraic Structures and Integrability of long-Short Wave Equation in （2＋1）Dimensions

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Communications in Theoretical Physics 2004年第6X期42卷 821-823页

作者： ZHAOXue-Qing lüjing-Fa CollegeofPhysics NankaiUniversityTianjin300071China

The hidden symmetry and integrability of the long-short wave equation in (2+1) dimensions are considered using the prolongation approach. The internal algebraic structures and their linear spectra are derived in detai... 详细信息

关键词：逼近延长流体力学长短波交互作用偏微分双线性方程法

Orbit control strategy for lagrange point orbits based on an analytical method

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Science China(Physics,Mechanics & Astronomy) 2013年第4期56卷 830-839页

作者： lü jing lU QiShao WANG Qi School of Aeronautics Science and Engineering Beihang University

The periodic or quasi-periodic orbits around collinear lagrange points present many properties that are advantageous for space missions. These lagrange point orbits are exponentially unstable. On the basis of an analytical method, an orbit control strategy that is designed to eliminate the dominant unstable components of lagrange point orbits is developed. The proposed strategy enables the derivation of the analytical expression of nonlinear control force. The control parameter of this strategy can be arbitrarily selected provided that the parameter is considerably lower than the negative eigenvalue of motion equations, and that the energy required keeps the same order of magnitude. The periodic or quasi-periodic orbit of controlled equations remains near the periodic or quasi-periodic orbit of uncontrolled equations.

关键词： analytical method control strategy lagrange point periodic or quasi-periodic orbit

Chiral （6,3） Network Assembled by lanthanide and Changeful Dihydroxyfumaric Acid

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Chinese Journal of Chemistry 2012年第2期30卷 228-232页

作者： Zhang,Manbo lü,jing Hu,Ruixiang Key laboratory of Chemical Biology&Traditional Chinese Medicine Research(Ministry of Education) College of Chemistry and Chemical EngineeringHunan Normal UniversityChangshaHunan 410081China

A series of chiral two-dimensional lanthanide coordination polymers, [ln2（l）3（H2O）6]n·n/3H2O[ln=Nd （la, lb）, Sm （2）, Eu （3）, Tb （4）, Dy （5）, Ho （6）, Er （7）; H2l=2,2-dihydroxylmalonic acid], have been hydrothermally synthesized by using dihydroxyfumaric acid as a source of polydentate O-donor ligands. The luminescence behav- iors of 3 and 4 have been investigated, and they exhibit strong red and green fluorescence in the visible region respectively.

关键词： chiral coordination polymer lanthanide dihydroxyfumaric acid 2,2-dihydroxylmalonate

Effects of Pairing Correlations on the Korringa Relation in Doped Fullerenes

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Chinese Physics letters 1996年第11期13卷 859-862页

作者： lÜjing ZHANG li-yuan FENG Xiao-bing Department of Physics Peking UniversityBeijing 100871

An effective attractive Hubbard model is applied to explain the observed non-Korringa relation in doped fullerenes,which leads to a reduced Pauli *** results basically agree with the experiments for K_(3)C_(60),Rb_(3)C_(60) and RbCs_(2)C_(60).It implies that the pair correlation on site possibly plays an important role in the normal state for doped fullerenes.

关键词： implies attractive Hubbard

Coupling dynamic analysis of a liquid-filled spherical container subject to arbitrary excitation

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Acta Mechanica Sinica 2012年第4期28卷 1154-1162页

作者： jing lü Shimin Wang Tianshu Wang School of Aeronautics Science and Engineering Beihang University100191 BeijingChina School of Aerospace Tsinghua University100084 BeijingChina

Using spherical coordinates, the coupling nonlinear dynamic system of a liquid-filled spherical tank, which can be excited discretionarily, is deduced by the H-O varia- tional principle, and the viscous damping is introduced via the liquid dissipation function. The kinetic equations of the coupling system are deduced by the relationship between the velocity of liquid particles and the disturbed liquid surface equation. Normal differential equations are obtained through the Galerkin method. An equivalent mechanical model is developed for liquid sloshing in a spherical tank subject to arbitrary excitation. The fixed and slosh masses, as well as the spring and damping constants, are determined in such a way as to satisfy the principle of equivalence. Numerical simulations illustrate the theoretical results in this paper as well.

关键词： liquid-filled spherical tank. Coupling nonlinear system Arbitrary excitation Equivalent mechanical model Spherical coordinates

The intra-day optical monitoring of Bl lacerate object 1ES 1218+304 at its highest X-ray flux level

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Research in Astronomy and Astrophysics 2021年第8期21卷 135-140页

作者： Si-Si Sun Hua-li li Xing Yang jing lü Da-Wei Xu jing Wang Guangxi Key laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China Key laboratory of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100101China

We here report a monitor of the Bl lac object 1 ES 1218+304 in both B-and R-bands by the GWAC-F60 A telescope in eight nights,when it was triggered to be at its highest X-ray flux in history by the VERITAS Observatory and Swift *** ANOVA and χ^(2)-test enable us to clearly reveal an intraday variability in optical wavelengths in seven out of the eight nights.A bluer-when-brighter chromatic relationship has been clearly identified in five out of the eight nights,which can be well explained by the shock-in-jet *** addition,a quasi-periodic oscillation phenomenon in both bands could be tentatively identified in the first night.A positive delay between the two bands has been revealed in three out of the eight nights,and a negative one in the other *** identified minimum time delay enables us to estimate the MBH=2.8 × 10^(7) M_(⊙) that is invalid.

关键词： Bl lacertae objects:general Bl lacertae objects:individual(1ES1218+304) galaxies:active method:statistical

Cobalt catalysts for Fischer–Tropsch synthesis： The effect of support,precipitant and pH value

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Chinese Journal of Chemical Engineering 2018年第4期26卷 747-752页

作者： zhenhua li mengyao si li xin renjie liu runxue liu jing lü Key lab for Green Chemical Technology of Ministry of Education School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

In this report,Co-based catalysts supported on ZnO,Al_2O_3 and ZrO_2 as well as the ZrO_2 derived from different precipitants and different pH values were prepared by co-precipitation *** catalytic Fischer–Tropsch synthesis(FTS)performance was investigated in a fixed-bed *** results revealed that Co catalyst supported on ZrO_2 exhibited better FTS catalytic performance than that supported on ZnO or Al_2O_*** the Co/ZrO_2catalyst,different precipitants showed the following an activity order of NaOH>Na_2CO_3>NH_4OH,and the best pH value is *** catalysts were characterized by N_2adsorption–desorption,XRF,XRD,H_2-TPR,H_2-TPD and *** was found that the main factor affecting the CO conversion of the catalyst was the amounts of low-temperature active adsorption ***,the selectivity of C_5^+hydrocarbons had a positive relationship with the peak temperature of the weak hydrogen adsorption *** higher the peak temperature,the higher the C_5^+selectivity is.

关键词： Fischer–Tropsch synthesis Co-precipitation Carbon monoxide Hydrogenation ZrO2

Extending the correlation of l_R-l_X to gamma-ray bursts

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Research in Astronomy and Astrophysics 2015年第5期15卷 617-622页

作者： jing l jing-Wen Xing Yuan-Chuan Zou Wei-Hua lei Qing-Wen Wu Ding-Xiong Wang GXU-NAOC Center for Astrophysics and Space Sciences Department of PhysicsGuangxi University Guangxi Key laboratory for Relativistic Astrophysics School of Physics Huazhong University of Science and Technology

The well-known correlation between radio luminosity （lR） and X-ray luminosity （lx）, lR/lX 10^-5, holds for a variety of objects, such as active galactic nuclei, Galactic black holes, solar flares and cool stars. Here we extend the relation to gamma-ray bursts （GRBs） and find that the GRBs also obey a similar lR - lX relation, with a slightly different slope of lR ∝ lX^1.1. This relation implies that the explosions that occur on different scales may have a common underlying origin.

关键词： gamma-ray bursts general -- quasars general -- stars black holes

Real atom economy and its application for evaluation the green degree of a process

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Frontiers of Chemical Science and Engineering 2011年第3期5卷 349-354页

作者： Weihan WANG jing lÜ li ZHANG Zhenhua lI Key laboratory for Green Chemical Technology School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Green chemistry has attracted more attention in the past *** the 12 principles of green chemistry,only atom economy and E factor can be expressed quantitatively to depict the impact of a chemical process to *** economy was thought better than the traditional yield for evaluating the atom efficiency of raw *** it is not enough to reﬂect the conversion degree of raw *** this paper,we proposed the concept of real atom economy(RAE)as a *** could combine the above two factors together to better express the green degree of a *** further suggested an equation to correlate E factor with *** concept of RAE is proved to be helpful for estimating an environmentally benign process.

关键词： green chemistry real atom economy E factor atom economy yield