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Effects of sunspot cycle length and CO_2 on air temperature along Qinghai-Xizang railway and air temperature's trend prediction

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Science china Earth Sciences 2004年第z1期47卷 131-141页

作者： LI Dongliang, QUO Hui, WANG Wen & WEI LiCold & Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Science, lanzhou 730000, china department of Atmospheric Sciences,{3., lanzhou 730000, china 1. Cold & Arid Regions Environmental and Engineering Research Institute Chinese Academy of Science 730000 Lanzhou China2. Department of Atmospheric Sciences Lanzhou University 730000 Lanzhou China

There are well coherences between annual averaged air temperatures at every meteorological station along the Qinghai-Xizang railway, and its 10-year moving average correlation coefficient is 0.92. Thus, the regional averaged annual mean temperature series along the Qinghai-Xizang railway (Trw) from 193. to 2000 are constructed. The investigation is suggested that: Trw had significant responses to the 5-year lagged sunspot cycle length (SCL) and 15-year lagged concentration of atmospheric carbon dioxide (CO2), and the correlation coefficients between them are -0.76 (SCL) and 0.88 (CO2), respectively. The future SCL is predicted by the model of average generated function constructed with its main cycles of 76a, 93., 108a, 205a and 275a. The result shows that the SCL would be becoming longer in the first half of the 21st century, and then it could be becoming shorter in the second half of the 21st century. Based on the natural change of SCL and the effect of double CO2 concentration, Trw in the 21st century is forecasted. It could warm up about 0.50℃ in the first half of the 21st century compared with the last decade of last century. The mean maximum air temperature could be likely about 0.20℃ in July and from 0.40℃ to 1.10℃ in January. The annual air temperature difference would likely reduce 0.3.1.00℃. The probability of above predictions ranges from 0.64 to 0.73.

关键词： Qinghai-Xizang railway, annual mean air temperature, sunspot cycle length (SCL), atmospheric carbon dioxide concentration (CO2), prediction.

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Oxyfunctionalization of ketones bearing α-methylene group with piperidine oxoammonium *** of α-diketones from monoketones

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Chinese Journal of Chemistry 1996年第3期14卷 252-258页

作者： LIU, You-Cheng REN, Tan GUO, Qing-Xiang National Laboratory of Applied Organic Chemistry, lanzhou university,lanzhou, Gansu 730000,{3. department of modern Chemistry, university of Science and Technology of{3.,Hefei, Anhui 23.026,{3. National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000 China department of modern Chemistry University of Science and Technology of China Hefei Anhui 230026 China National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000 China National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000 China department of modern Chemistry University of Science and Technology of China Hefei Anhui 230026 China [*]Address correspondence to this author at university of Science and Technology of china.

A facile method for the title transformation is described. The reaction of 2,2,6,6-tetramethyl-4-methoxypiperidine oxoammonium chloride (1b) and ketones bearing a-methylene group in acetonitrile proceeded smoothly to give the a-oxyfunctionalized coupling products (6a-h). These coupling products decomposed upon heating in acidic medium to produce a-diketones (7a-h) in good to excellent yields.

关键词： Piperidine oxoammonium salt monoketones,α-diketones synthesis

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Effects of additives on the aggregation of surfactants: binding domination

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Chinese Journal of Chemistry 1992年第3期10卷 237-244页

作者： LEI, Xue-Gong department of Chemistry, lanzhou university, lanzhou 730000 department of Chemistry Lanzhou University Lanzhou 730000

The effects of electrolytes, alcohols, and urea on the aggregation of SDS, CTAB, and Triton X-100 at 25℃ have been investigated by fluorescence probing of pyrene. Both electrolytes and alcohols reduce the critical micelle concentration (CMC) of the ionic surfactants, while the effect of the former is more pronounced. It is shown that the effects of electrolytes mainly depend on the concentrations and especially the valence of the opposite charge ions, and only slightly depend on the same charge ions in respect of ion aggregate of micelle. The logarithm of CMC is not linearly correlated with the concentrations of the counter ion or the electrolytes. The results are rationalized in terms of Hartley's model. Propanol increases the CMC of TX-100, while electrolytes and urea do not. In all the three kinds of surfactant micelles the excitation spectrum of pyrene slightly red-shifts (ca. 4 nm) from that in water, but is not affected by the additives. The micropolarity of the environment in which pyrene molecule resides in SDS micelle decreases with the increase of the concentrations of electrolytes. This is not the case when alcohols and urea were added to SDS or to TX-100. It is suggested that the addition of electrolytes would result in more orderly orientation of SDS molecules. It is the binding strength of the counter ions that dominates the effects of additives on the aggregation of surfactants.

关键词： CMC binding domination Effects of additives on the aggregation of surfactants

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Robustness and breakup of the spiral wave in a two-dimensional lattice network of neurons

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Science china(phys.cs,Mechanics & Astronomy) 2010年第4期53卷 672-679页

作者： MA Jun 1,2, TANG Jun 2 , ZHANG AiHua 3.& JIA Ya 2 1 department of phys.cs, lanzhou university of Technology, {3. 73.050, china 2 department of phys.cs, Central china Normal university, Wuhan 43.079, china 3.College of Electrical and Information Engineering, lanzhou university of Technology, {3. 73.050, china 1. department of phys.cs Lanzhou University of Technology Lanzhou 730050 China2. Department of Physics Central China Normal University Wuhan 430079 China3. College of Electrical and Information Engineering Lanzhou University of Technology Lanzhou 730050 China

The robustness and breakup of spiral wave in a two-dimensional lattice networks of neurons are investigated. The effect of small- world type connection is often simplified with local regular connection and the long-range connection with certain probability. The network effect on the development of spiral wave can be better described by local regular connection and changeable long-range connection probability than fixed long-range connection probability because the long-range probability could be changeable in realistic biological system. The effect from the changeable probability for long-range connection is simplified by multiplicative noise. At first, a stable rotating spiral wave is developed by using appropriate initial values, parameters and no-flux boundary conditions, and then the effect of networks is investigated. Extensive numerical studies show that spiral wave keeps its alive and robust when the intensity of multiplicative noise is below a certain threshold, otherwise, the breakup of spiral wave occurs. A statistical factor of synchronization in two-dimensional array is defined to study the phase transition of spiral wave by checking the membrane potentials of all neurons corresponding to the critical parameters(the intensity of noise or forcing current)in the curve for factor of synchronization. The Hindmarsh-Rose model is investigated, the Hodgkin-Huxley neuron model in the presence of the channel noise is also studied to check the model independence of our conclusions. And it is found that breakup of spiral wave is easier to be induced by the multiplicative noise in presence of channel noise.

关键词： spiral wave factor of synchronization breakup multiplicative noise robustness

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X-ray spectra induced by slow highly charged Ar^(q+) ions in collision with Nb surface

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Science china(phys.cs,Mechanics & Astronomy) 2008年第10期51卷 1463-1469页

作者： YANG ZhiHu1, CUI Ying2, CHEN XiMeng2, SONG ZhangYong1, SHAO JianXiong2, RUAN FangFang1, ZHANG HongQiang2, DU Juan2, LIU YuWen2, GAO ZhiMing2, ZHANG XiaoAn3. ZHU KeXin1, YU DeYang1 & CAI XiaoHong1 1 Institute of modern phys.cs, Chinese Academy of Sciences, lanzhou 730000,{3. 2 department of modern phys.cs, lanzhou university, lanzhou 730000,{3. 3.department of phys.cs, Xianyang Normal College, Xianyang 712000,{3. 1. Institute of modern phys.cs Chinese Academy of Sciences Lanzhou 730000 China 2. department of modern phys.cs Lanzhou University Lanzhou 730000 China 3. department of phys.cs Xianyang Normal College Xianyang 712000 China

The X-ray spectra of Nb surface induced by Arq+ (q =16,17) ions with the energy range from 10 to 20 keV/q were studied by the optical spectrum technology. The experimental results indicate that the multi-electron excitation occurred as a highly charged Ar16+ ion was neutralized below the metal surface. The K shell electron of Ar16+ was excited and then de-excited cascadly to emit K X-ray. The intensity of the X-ray emitted from K shell of the hollow Ar atom decreased with the increase of projectile kinetic energy. The intensity of the X-ray emitted from L shell of the target atom Nb increased with the increase of projectile kinetic energy. The X-ray yield of Ar17+ is three magnitude orders larger than that of Ar16+.

关键词： highly charged ion hollow atom multi-electron X-ray

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A NONLINEAR GALERKIN METHOD WITH VARIABLEMODES FOR KURAMOTO-SIVASHINSKY EQUATION

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Journal of Computational Mathematics 1999年第3期17卷 243-256页

作者： Yu-jiang wu(Depadrtment of Mathematics, Shanghai university, Jiadiap Shanghai 201800, china department of Mathematics,{3., lanzhou 750000, china) 上海大学数学系上海

This article proposes a kind of nonlinear Galerkin methods with variable modes for the long-term integration of Kuramoto-Sivashinsky equation. It consists of finding an appropriate or best number of modes in the correction of the method. Convergence results and error estimates are derived for this method. Numerical examples show also the efficiency and advantage of our method over the usual nonlinear Galerkin method and the classical Galerkin method.

关键词： Kuramoto-Sivaskinsky equation nonlinear Galerkin method approximation convergence

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POSITIVE　SOLUTIONS　FOR　DIRICHLET　PROBLEMS　OF　SINGULAR　SEMILINEAR　ELLIPTIC　EQUATIONS

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Systems Science and Mathematical Sciences 1995年第3期8卷 203-208页

作者： CUI Shangbin(department of Mathematics, lanzhou university, lanzhou 730000,{3.) 兰州大学数学系甘肃兰州

ＰＯＳＩＴＩＶＥＳＯＬＵＴＩＯＮＳＦＯＲＤＩＲＩＣＨＬＥＴＰＲＯＢＬＥＭＳＯＦＳＩＮＧＵＬＡＲＳＥＭＩＬＩＮＥＡＲＥＬＬＩＰＴＩＣＥＱＵＡＴＩＯＮＳ￥ＣＵＩＳｈａｎｇｂｉｎ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉ... 详细信息

ＰＯＳＩＴＩＶＥＳＯＬＵＴＩＯＮＳＦＯＲＤＩＲＩＣＨＬＥＴＰＲＯＢＬＥＭＳＯＦＳＩＮＧＵＬＡＲＳＥＭＩＬＩＮＥＡＲＥＬＬＩＰＴＩＣＥＱＵＡＴＩＯＮＳ￥ＣＵＩＳｈａｎｇｂｉｎ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＬａｎｚｈｏｕＵｎｉｖｅｒｓ...

关键词： Singular semilinear elliptic equation Dirichlet problem positive solution.

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The Regularity of Lagrangians f(x,ξ) = |ξ|^(α(x)) with Holder Exponents α(x)

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Acta Mathematica Sinica,English Series 1996年第3期12卷 254-261页

作者： Fan Xianling, department of Mathematics lanzhou university lanzhou, {3. china department of Mathematics lanzhou university lanzhou 730000 China

In this paper the regularity of the Lagrangians f（x,ζ）=|ζ|α（x）（11 α（x） α2α（x） is regular. This result gives a negative answer to a conjecture of V. Zhikov.

关键词： Lagrangians Integrals Sobolev spaces Regularity

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THE CLAR FORMULAS OF REGULAR t-TIER STRIP BENZENOID SYSTEMS

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Systems Science and Mathematical Sciences 1995年第4期8卷 327-337页

作者： ZHANG Heping(department of Mathematics,lanzhou university,lanzhou 730000,china) 兰州大学数学系甘肃兰州

ＴＨＥＣＬＡＲＦＯＲＭＵＬＡＳＯＦＲＥＧＵＬＡＲｔ－ＴＩＥＲＳＴＲＩＰＢＥＮＺＥＮＯＩＤＳＹＳＴＥＭＳＴＨＥＣＬＡＲＦＯＲＭＵＬＡＳＯＦＲＥＧＵＬＡＲｔ－ＴＩＥＲＳＴＲＩＰＢＥＮＺＥＮＯＩＤＳＹＳＴＥＭＳ￥ＺＨＡＮＧ... 详细信息

ＴＨＥＣＬＡＲＦＯＲＭＵＬＡＳＯＦＲＥＧＵＬＡＲｔ－ＴＩＥＲＳＴＲＩＰＢＥＮＺＥＮＯＩＤＳＹＳＴＥＭＳＴＨＥＣＬＡＲＦＯＲＭＵＬＡＳＯＦＲＥＧＵＬＡＲｔ－ＴＩＥＲＳＴＲＩＰＢＥＮＺＥＮＯＩＤＳＹＳＴＥＭＳ￥ＺＨＡＮＧＨｅｐｉｎｇ（Ｄｅｐａｒｔｍｅｎｔ...

关键词： Benzenoid system perfect matching Clar formula.

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Synthesis and Characterization of New Schiff Base and Polyoxa-azaCryptands and Their Rare Earth Cryptates with [1+1] Condensation and Reduction Methods

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Chinese Chemical Letters 1999年第12期10卷 995-998页

作者： Zhen MA Ru Dong YANG Lan YAN(department of Chemistry, lanzhou university, lanzhou, Gansu {3.) lanzhou Univ Dept Chem Lanzhou 730000 Peoples R China

The Schiff base cryptand and its cryptates were synthesized with the methods of [1+1] condensation of trialdehyde and tris(2-aminoethyl)amine and obtained in 60-65%, 5-25% and 70-80% yields respectively with or without some rare earth elements as templates. The polyoxa-aza cryptand was produced in 72% and 60-70% yields with reduction of Schiff base and its cryptates respectively.

关键词： Schiff base polyoxa-aza cryptand rare earth condensation

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