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New Positive and Negative Hierarchies of Integrable Differential-Difference Equations and Conservation Laws

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Communications in Theoretical Physics 2009年第1期51卷 17-22页

作者： LI Xin-Yue zhao qiu-Lan College of Science Shandong University of Science and Technology Qingdao 266510 China

Two hierarchies of nonlinear integrable positive and negative lattice equations are derived from a discrete spectrak problem. The two lattice hierarchies are proved to have discrete zero curvature representations associated with a discrete spectral problem, which also shows that the positive and negative hierarchies correspond to positive and negative power expansions of Lax operators with respect to the spectral parameter, respectively. Moreover, the integrable lattice models in the positive hierarchy are of polynomial type, and the integrable lattice models in the negative hierarchy are of rational type. Further, we construct infinite conservation laws about the positive hierarchy.

关键词： discrete zero curvature equations Liouville integrability discrete Hamiltonian structure conservation laws

Synthesis and Crystal Structure of a New Complex [CuL(Phen)]·NO_3

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1343-1346页

作者： qiu Xiao-Hang zhao Jun TONG Xiao-Lan Department of Chemistry Nankai University Tianjin 300071 China

A new mononuclear copper（Ⅱ） complex [CuL（Phen）]-NO3 （L - 2-{2-[（3,5-dibro- mosalicylidene）amino]ethyl }- 1 H- 1,3-benzimidazole, Phen = 1,10-phenanthroline） has been synthesized and its crystal structure was determined by X-ray diffraction method. It crystallizes in monoclinic, space group C2/c with a = 24.966（7）, b = 15.673（4）, c = 16.600（5） A,β = 123.981（4）°, C28H20Br2CuN604, Mr = 727.86, V = 5386（2） A^3, Z = 8, Dc = 1.795 g/cm^3,μ（MoKα = 3.826 mm^-1, F（000） = 2888, the final R = 0.0508 and wR = 0.1024 for 5440 independent reflections with Rint = 0.1134. The title compound is composed of [CuL（Phen）]＋ cation and NO3^- anion. The coordination geometry around copper atom is a highly distorted trigonal bipyramid consisting of one benzimidazole nitrogen atom, one phenolato oxygen atom and one phenanthroline nitrogen atom on the equatorial plane together with one imine nitrogen atom and one phenanthroline nitrogen atom occupying the axial positions. The hydrogen bonding and π-π stacking interactions link the copper complex molecules into a 3-D supramolecular structure.

关键词： crystal structure copper complex 1,10-phenanthroline hydrogen bonds

Distribution of Welding Residual Stress of Mixed Steel U-Rib-Stiffened Plates

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Transactions of Tianjin University 2018年第5期24卷 489-500页

作者： qiu zhao Zhansheng Zhai Yu Nie College of Civil Engineering Fuzhou University

To analyze the effects of width and thickness of each composition element of mixed steel U-rib-stiffened plates on the welding residual stress distribution, the distribution of the U-rib and the plate residual stress was calculated using a simplified calculation method. The method involved welding the mixed steel U-rib-stiffened plates for a structure with different sizes and different strength ratios of U-rib to plate. Based on a welding residual stress numerical simulation method validated by the blind hole method test, the distribution law of the mixed steel U-rib stiffened plate was studied. The results showed that the change of plate width has little impact on the welding residual stress and that the ratio of the thicknesses of the plate to U-rib stiffeners, the thickness of the plate, and the thickness of the U-rib has a great influence on the distribution of the welding residual stress. The thickness of plate and steel strength also greatly influenced the distribution width of the residual tensile stress. While analyzing the compression capacity of U-rib-stiffened plates, the simplified distribution of welding residual stress was used.

关键词： Steel bridge Welding residual stress Simplifi ed calculation method U-rib stiff ened plate Finite element method

Sodium Enrichment in Yellow Supergiants:a Perspective from the Uncertainties of Reaction Rates

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Chinese Journal of Astronomy and Astrophysics 2008年第6期8卷 700-706页

作者： Lei zhao qiu-He Peng Xin-Lian Luo Department of Astronomy Nanjing University Nanjing 210093 China

Sodium overabundance in yellow supergiants has stumped people for more than 20 years. The purpose of this paper is to explore this problem from the perspective of nuclear physics. We investigate carefully the CNO and NeNa cycles that are responsible for sodium production. We investigate some key reactions in the appropriate network. We show whether and how the sodium output can be affected by the rate uncertainties in these reactions. In this way, we evaluate if a reaction is important enough to deserve a better determination of its rate in terrestrial laboratories.

关键词： nuclear reactions nucleosynthesis stars: abundances supergiants

Numerical simulation of preparation of ultrafine cerium oxides using jet-flow pyrolysis

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Rare Metals 2019年第12期38卷 1160-1168页

作者： Chao Lv Ting-An Zhang Zhi-He Dou qiu-Yue zhao Key Laboratory of Ecological Metallurgy of Multi-metal Intergrown Ores of Ministry of Education Special Metallurgy and Process Engineering InstituteNortheastern UniversityShenyang 110819China School of Control Engineering Northeastern University at QinhuangdaoQinhuangdao 066004China

Ultrafine rare-earth oxides(REOs) are widely applied in all fields of daily life,but the conventional preparation methods are limited by a long procedure,low efficiency and severe environmental *** team has independently developed a jet pyrolysis reactor for the preparation of ultrafine cerium oxides,and this process has theoretical significance and practical application *** this study,gas-solid pyrolysis reactions inside the jet-flow pyrolysis reactor were numerically *** performed a coupling computation of the combustion,phase transformation and gas-solid reaction on Fluent and userdefined *** characterized the flows of different phases as well as the compositions and distributive laws of the reactants/products in the *** gas-phase inlet velocity and dynamic pressure/additional pressure were related by a quadratic *** velocity at the throat inlet changed the most,and the outlet velocity was very *** CeO2 concentrations were obviously *** study enriches theories of jet-flow pyrolysis and theoretically underlies the optimization and popularization of self-developed pyrolysis reactors.

关键词： Jet-flow Pyrolysis Reactor Cerium oxides Numerical simulation

Early expression of surfactant proteins D in Fusarium solani infected rat cornea

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International Journal of Ophthalmology(English edition) 2012年第3期5卷 297-300页

作者： Cheng-Ye Che, Gui-qiu zhao Department of Ophthalmology the Affiliated Hospital of Qingdao University Qingdao 266003 Shandong Province China Binzhou Hubin Eye Hospital Binzhou 256600 Shandong Province China

AIM: To investigate the early expression of surfactant proteins D(SP-D) in Fusarium solani infected rat cornea. METHODS: Wistar rats were divided into group A, B and C randomly. The right eyes were chosen as the experiment one. Group A was control group. Group B was not inoculated with Fusarium solani. Group C was taken as fusarium solani keratitis model. Five rats in group B and C were executed randomly at 6, 12, 24, 48 and 96 hours respectively after the experimental model being established. The expression of SP-D was assessed through immunohistochemistry and reverse transcription polyrnerase chain reaction(RT-PCR). RESULTS: RT-PCR detected that the SP-D mRNA expression was low in the corneal of normal rats and group B. The expression of fungal infected cornea increased gradually and reached the peak at 24 hours in group C. The synchronous expression of group B and C were in significant difference (P<0.01). Immunohistochemisty discovered the protein of SP-D expression was increased gradually from 12 hours and reached the peak at 48 hours in group C. The synchronous expression of group B and C were also in significant difference (P<0.01). CONCLUSION: There exists SP-D in rat corneal tissue and the expression is significantly increased at the early period of fusarium solani infected cornea. SP-D may play a role in the early innate immunity response of the corneal resistance to Fusarium solani infection.

关键词： keratitis Fusarium solani surfactant protein D innate immune

Effect of Climate Variability and Human Activities on Runoff in the Jinghe River Basin, Northwest China

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Journal of Mountain Science 2015年第2期12卷 358-367页

作者： YAO Jun-qiang zhao qiu-dong LIU Zhi-hui School of Resources and Environment Science Key Laboratory of Oasis Ecology of Ministry of Education Xinjiang University Xinjiang Climate Center Xinjiang Meteorological Administration Institute of Desert Meteorology China Meteorological Administration Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Institute of Arid Ecology and Environment Xinjiang University

Much attention has recently been focused on the effects of climate variability and human activities on the runoff. In this study, we analyzed 56-yr(1957–2012) runoff change and patterns in the Jinghe River Basin(JRB) in the arid region of northwest China. The nonparametric Mann–Kendall test and the precipitation-runoff double cumulative curve(PRDCC) were used to identify change trend and abrupt change points in the annual runoff. It was found that the runoff in the JRB has periodically fluctuated in the past 56 yr. Abrupt change point in annual runoff was identified in the JRB, which occurred in the years around 1964 and 1996 dividing the long-term hydrologic series into a natural period(1957 – 1964) and a climate and man-induced period(1965 – 1996 and 1997 – 2012). In the 1965 – 1996 period, human activities were the main factor that decreased runoff with contribution of 88.9%, while climate variability only accounted for 11.1%. However,the impact of climate variability has been increased from 11.1% to 47.5% during 1997 – 2012, showing that runoff in JRB is more sensitive to climate variability during global warming. This study distinguishes theeffect of climate variability from human activities on runoff, which can do duty for a reference for regional water resources assessment and management.

关键词： Water resource Runoff Climate variability Precipitation Jinghe River Basin

Numerical simulation:preparation of La_2O_3 in a jet pyrolysis reactor

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Rare Metals 2015年第8期34卷 600-606页

作者： Chao Lv Zi-Mu Zhang qiu-Yue zhao Zhi-He Dou Ting-An Zhang Hong-Liang zhao Key Laboratory of Ecological Utilization of Multi-metal Intergrown Ores of Ministry of Education School of Materials and Metallurgy Northeastern University Department of Mathematics Northeast Petroleum University at Qinhuangdao

Based on the technique for preparing La Cl3 via direct pyrolysis of rare earth chloride solution, a jet pyrolysis reactor was designed and the intra-reactor temperature and chemical reactions were numerically simulated using computational fluid dynamics(CFD) *** results show that the flow rate variation at the fuel inlet does not largely affect the temperature in the reactor, while the increase in external pressure at the material inlet rapidly decreases the average temperature, Venturi temperature, and outlet temperature. The CH4 and O2inside the reactor are combusted completely, and when the material inlet pressure is \90 Pa, the La Cl3 is fully pyrogenated. The contents of CO2, La2O3, and HCl fluctuate near the Venturi tube and finally stabilize. La2O3 content at the outlet is in a top-to-bottom gradient.

关键词： Jet-flow Pyrolysis Chemical reaction Numerical sim

SNR-based weighted cooperative spectrum sensing in cognitive radio networks

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The Journal of China Universities of Posts and Telecommunications 2010年第2期17卷 1-7页

作者： WU Su-wen ZHU Jin-kang qiu Ling zhao Ming Department of Electronic Engineering and Information Science University of Science and Technology of China Hefei 230027 China

Cooperative spectrum sensing （CSS） is an approach to confront fading environment. However, in conventional cooperative spectrum sensing （CCSS）, the difference among the secondary users （SUs） is ignored when SUs suffer from different fading. In this article, a signal-to-noise ratio （SNR）-based weighted spectrum sensing scheme is proposed to improve the sensing performance. The sensing performance of the weighted spectrum sensing scheme is then derived. Considering the minor contribution of the SUs with small weighted factor, a selective CSS scheme is proposed, where SUs with low SNR are not selected into cooperative spectrum sensing. The simulation results conftrm the analytical results. And the performance of weighted scheme is better than that of conventional schemes. In the case where the SNR of SUs are randomly distributed, the performance of selective scheme is almost the same as the weighted scheme while the number of cooperative SUs is reduced to save the consumption of system resource in cooperation with little additional complexity.

关键词： cooperative spectrum sensing SNR-based weighted secondary users