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Effects of Samarium on Liver and Kidney of Rats 被引量:4
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作者 施维林 申秀英 马锡英 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第z2期415-418,共4页
Spraque-Dawley(SD)big rats with weaning weight of (195±15) g were randomly divided into 4 groups with 8 males and 8 females each group. One group drank de-ionized water served as control and also used for analysi... Spraque-Dawley(SD)big rats with weaning weight of (195±15) g were randomly divided into 4 groups with 8 males and 8 females each group. One group drank de-ionized water served as control and also used for analysis with the background. The other three groups were cultured for five months by drinking de-ionized water with 3.0, 4.5 and 6.0 mg·L-1 Sm (NO3)3, respectively. Compared with the rats in control, it is found that the organs of the treated rats are apparently pathologically changed, such as liver swell, lung intumescence, peritoneum conglutination and hardness. Especially, in the high Sm group, the pathological percentage in liver and lung is up to 30% . The pathological changes in liver and lung show that rare earth Sm does hazard biological effects to animals. With increasing Sm concentration, the weight rate of organ/body has a tendency of increasing; the activity of superoxide dismutase (SOD) in liver and kidney decreases, but the maglonydiadehyde (MDA) concentration increases, indicating the abilities of anti-oxidation and the lipid per-oxi-dation inhibition degenerate, which leads to hard pathological changes in organs. Moreover, the relative weight rate of organ/body, the activity of SOD and the MDA concentration are remarkably lager in liver than in kidney and other organs, suggesting that the biological effect of Sm on liver is the greatest and Sm has a high affinity for liver. 展开更多
关键词 SAMARIUM biology effects SOD MDA rare earths
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Decline of eucalypt trees in tablelands of New South Wales, Australia 被引量:6
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作者 ZHANG Yan-hua SUN Li-fu Ken C. Hodgkinson 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第4期306-310,共5页
Eucalyptus species are the native and major plant group in Australian landscapes. Since European settlement, eucalypt trees heavily decline in the tablelands .of New South Wales. Tree recruitment bog down and the land... Eucalyptus species are the native and major plant group in Australian landscapes. Since European settlement, eucalypt trees heavily decline in the tablelands .of New South Wales. Tree recruitment bog down and the landscape ecosystem hardly recovers to the original state. This paper introduces the history of eucalypt trees and native shrubs decline, analyzes reasons of seedling recruitment decrease in this region, such as clearing, grazing, fire, competition from exotic species, dieback, insects, drought and so on, and summarizes the probable conditions of eucalypt tree recruitment, such as suitable conditions of seedling survival, sufficient seed supply, keep from predation, suitable germination conditions, non-grazed environment, mechanical treatment, weed control, fire regime, disease control etc, lending suggests how to preserve and encourage eucalypt trees recruitment in the area. 展开更多
关键词 EUCALYPT DECLINE RECRUITMENT
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The construction of conserved quantities for linearly coupled oscillators and study of symmetries about the conserved quantities 被引量:3
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作者 楼智英 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第5期1182-1185,共4页
In this paper, the conserved quantities are constructed using two methods. The first method is by making an ansatz of the conserved quantity and then using the definition of Poisson bracket to obtain the coefficients ... In this paper, the conserved quantities are constructed using two methods. The first method is by making an ansatz of the conserved quantity and then using the definition of Poisson bracket to obtain the coefficients in the ansatz. The main procedure for the second method is given as follows. Firstly, the coupled terms in Lagrangian are eliminated by changing the coordinate scales and rotating the coordinate axes, secondly, the conserved quantities are obtain in new coordinate directly, and at last, the conserved quantities are expressed in the original coordinates by using the inverse transform of the coordinates. The Noether symmetry and Lie symmetry of the infinitesimal transformations about the conserved quantities are also studied in this paper. 展开更多
关键词 linear coupled oscillator conserved quantity Noether symmetry Lie symmetry
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The Lagrangian and the Lie symmetries of charged particle motion in homogeneous electromagnetic field 被引量:2
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作者 楼智美 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第5期891-894,共4页
In this paper, a constant of motion of charged particle motion in homogeneous electromagnetic field is derived from Newton's equations and the characteristics of partial differential equation, the related Lagrangian ... In this paper, a constant of motion of charged particle motion in homogeneous electromagnetic field is derived from Newton's equations and the characteristics of partial differential equation, the related Lagrangian is also given by means of the obtained constant of motion. By discussing the Lie symmetry for this classical system, this paper obtains the general expression of the conserved quantity, It is shown that the conserved quantity is the same as the constant of motion in essence, 展开更多
关键词 constant of motion LAGRANGIAN Lie symmetry conserved quantity
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KUHN-TUCKER CONDITION AND WOLFE DUALITY OF PREINVEX SET-VALUED OPTIMIZATION 被引量:2
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作者 盛宝怀 刘三阳 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第12期1655-1664,共10页
The optimality Kuhn-Tucker condition and the wolfe duality for the preinvex set-valued optimization are investigated. Firstly, the concepts of alpha-order G-invex set and the alpha-order S-preinvex set-valued function... The optimality Kuhn-Tucker condition and the wolfe duality for the preinvex set-valued optimization are investigated. Firstly, the concepts of alpha-order G-invex set and the alpha-order S-preinvex set-valued function were introduced, from which the properties of the corresponding contingent cone and the alpha-order contingent derivative were studied. Finally, the optimality Kuhn-Tucker condition and the Wolfe duality theorem for the alpha-order S-preinvex set-valued optimization were presented with the help of the alpha-order contingent derivative. 展开更多
关键词 preinvex set-valued function contingent epiderivatives optimality conditions DUALITY
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Off-axial elliptical cosine-Gaussian beams and their propagation properties 被引量:1
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作者 吕章德 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第5期1320-1326,共7页
In this paper, a new kind of light beam called off-axial elliptical cosine-Gaussian beam (ECosGBs) is defined by using the tensor method. An analytical propagation expression for the ECosGBs passing through axially ... In this paper, a new kind of light beam called off-axial elliptical cosine-Gaussian beam (ECosGBs) is defined by using the tensor method. An analytical propagation expression for the ECosGBs passing through axially nonsymmetrical optical systems is derived by using vector integration. The intensity distributions of ECosGBs on the input plane, on the output plane with the equivalent Fresnel number being equal to 0.1 and on the focal plane are respectively illustrated for the propagation properties. The results indicate that an ECosGB is eventually transformed into an elliptical cosh- Gaussian beam. In other words, ECosGBs and cosh-Gaussian beams act in a reciprocal manner after propagation. 展开更多
关键词 elliptical cosine-Gaussian beams nonsymmetrical optical systems diffraction integral
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Influence of Samarium on Learning and Memory Function of Rats
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作者 施维林 申秀英 马锡英 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第z2期419-422,共4页
Sixty-four Spraque-Dawley (SD) big rats with weaning weight of (195 qqqqqq 15) g were randomly divided into 4 groups with 8 males and 8 females each group. One group drunk with de-ionized water served as control and w... Sixty-four Spraque-Dawley (SD) big rats with weaning weight of (195 qqqqqq 15) g were randomly divided into 4 groups with 8 males and 8 females each group. One group drunk with de-ionized water served as control and was also used for analysis of the background. The other three groups rats were raised by de-ionized water containing low, middle and high concentrations of Sm for four months, then learning and memory tests were carried out in Y-electric maze. Compared with the control rats, the learning and memory of rats in low and middle groups shows a deterioration trend, exhibiting the function degradation of rats' brain. It may results from the rare earth elements through blood-brain barrier affecting the normal physiological functions of rats' brain. In addition, the activity of superoxide dismutase (SOD) in rals' brain tie-creases , while the content of malondialdehyde (MDA.) concentration increases. The decreased SOD activity and the increased MDA mean the degeneration the ability of anti-oxidation in rats' brain, which are accordance with the degradation of learning and memory function of rats in low and middle Sm groups. 展开更多
关键词 SAMARIUM learning-memory SOD MDA rare earth element
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APPLICATIONS OF THE BERNSTEIN-DURRMEYER OPERATORS IN ESTIMATING THE NORM OF MERCER KERNEL MATRICES 被引量:2
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作者 Chunping Zhang Baohuai Sheng Zhixiang Chen 《Analysis in Theory and Applications》 2008年第1期74-86,共13页
The paper is related to the norm estimate of Mercer kernel matrices. The lower and upper bound estimates of Rayleigh entropy numbers for some Mercer kernel matrices on [0, 1] × [0, 1] based on the Bernstein-Durrm... The paper is related to the norm estimate of Mercer kernel matrices. The lower and upper bound estimates of Rayleigh entropy numbers for some Mercer kernel matrices on [0, 1] × [0, 1] based on the Bernstein-Durrmeyer operator kernel are obtained, with which and the approximation property of the Bernstein-Durrmeyer operator the lower and upper bounds of the Rayleigh entropy number and the l2 -norm for general Mercer kernel matrices on [0, 1] x [0, 1] are provided. 展开更多
关键词 Mercer kernel matrix Rayleigh entropy number Bernstein-Durrmeyer operator
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AN APPLICATION OF BERNSTEIN-DURRMEYER OPERATORS 被引量:2
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作者 Baohuai Sheng Chunping Zhang 《Analysis in Theory and Applications》 2007年第1期16-25,共10页
In the present paper, we find that the Bernstein-Durrmeyer operators, besides their better applications in approximation theory and some other fields, are good tools in constructing translation network. With the help ... In the present paper, we find that the Bernstein-Durrmeyer operators, besides their better applications in approximation theory and some other fields, are good tools in constructing translation network. With the help of the de la Vallée properties of the Bernstein-Durrmeyer operators a sequence of translation network operators is constructed and its degree of approximation is dealt. 展开更多
关键词 Bernstein-Durrmeyer operator translation network APPROXIMATION
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Direct method of finding first integral of two-dimensional autonomous systems in polar coordinates 被引量:1
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作者 楼智美 汪文珑 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第5期895-898,共4页
A direct method to find the first integral for two-dimensional autonomous system in polar coordinates is suggested. It is shown that if the equation of motion expressed by differential 1-forms for a given autonomous H... A direct method to find the first integral for two-dimensional autonomous system in polar coordinates is suggested. It is shown that if the equation of motion expressed by differential 1-forms for a given autonomous Hamiltonian system is multiplied by a set of multiplicative functions, then the general expression of the first integral can be obtained, An example is given to illustrate the application of the results. 展开更多
关键词 direct method autonomous systems first integral polar coordinates
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Projection type neural network and its convergence analysis 被引量:1
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作者 Youmei LI Feilong CAO 《控制理论与应用(英文版)》 EI 2006年第3期286-290,共5页
Projection type neural network for optimization problems has advantages over other networks for fewer parameters , low searching space dimension and simple structure. In this paper, by properly constructing a Lyapunov... Projection type neural network for optimization problems has advantages over other networks for fewer parameters , low searching space dimension and simple structure. In this paper, by properly constructing a Lyapunov energy function, we have proven the global convergence of this network when being used to optimize a continuously differentiable convex function defined on a closed convex set. The result settles the extensive applicability of the network. Several numerical examples are given to verify the efficiency of the network. 展开更多
关键词 Neural network Convex programming Global convergence Equilibrium points
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A Bilinear Backlund Transformation and Lax Pair for a (1+1)-Dimensional Differential-Difference sine-Gordon Equation 被引量:1
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作者 QIAN Xian-Min Hon-Wah Tam 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第3X期487-490,共4页
In this paper, we obtain a 1+1 dimensional integrable differential-difference model for the sine-Gordon equation by Hirota's discretization method. A bilinear Backlund transformation and the associated Lax pair are ... In this paper, we obtain a 1+1 dimensional integrable differential-difference model for the sine-Gordon equation by Hirota's discretization method. A bilinear Backlund transformation and the associated Lax pair are also proposed/or this model. 展开更多
关键词 sine-Gordon equation Hirota's discretization method Backlund transformation Lax pair
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Immune Genetic Learning of Fuzzy Cognitive Map 被引量:1
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作者 林春梅 何跃 汤兵勇 《Journal of Donghua University(English Edition)》 EI CAS 2006年第6期10-14,24,共6页
This paper presents a hybrid methodology of automatically constructing fuzzy cognitive map (FCM). The method uses immune genetic algorithm to learn the connection matrix of FCM. In the algorithm, the DNA coding method... This paper presents a hybrid methodology of automatically constructing fuzzy cognitive map (FCM). The method uses immune genetic algorithm to learn the connection matrix of FCM. In the algorithm, the DNA coding method is used and an immune operator based on immune mechanism is constructed. The characteristics of the system and the experts' knowledge are abstracted as vaccine for restraining the degenerative phenomena during evolution so as to improve the algorithmic efficiency. Finally, an illustrative example is provided, and its results suggest that the method is capable of automatically generating FCM model. 展开更多
关键词 FCM IMMUNE DNA coding genetic algorithm system modeling.
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The optimum design of the pressure control spring of the relief valve based on neural networks 被引量:1
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作者 傅晓锦 《Journal of Coal Science & Engineering(China)》 2006年第1期119-123,共5页
Based on the traditional optimization methods about the pressure control spring of the relief valve and combined with the advantages of neural network, this paper put forward the optimization method with many paramete... Based on the traditional optimization methods about the pressure control spring of the relief valve and combined with the advantages of neural network, this paper put forward the optimization method with many parameters and a lot of constraints based on neural network. The object function of optimization is transformed into the energy function of the neural network and the mathematical model of neural network optimization about the pressure control spring of the relief valve is set up in this method which also puts for ward its own algorithm. An example of application shows that network convergence gets stable state of minimization object function E, and object function converges to the utmost minimum point with steady function, then best solution is gained, which makes the design plan better. The algorithm of solution for the problem is effective about the optimum design of the pressure control spring and improves the performance target. 展开更多
关键词 SPRING neural networks optimal design relief valve
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APPLICATIONS OF BERNSTEIN-DURRMEYER OPERATORS IN ESTIMATING THE COVERING NUMBER 被引量:1
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作者 Chunping Zhang Jianli Wang Baohuai Sheng 《Analysis in Theory and Applications》 2010年第2期186-200,共15页
The paper deals with estimates of the covering number for some Mercer kernel Hilbert space with Bernstein-Durrmeyer operators. We first give estimates of l2- norm of Mercer kernel matrices reproducing by the kernelsK... The paper deals with estimates of the covering number for some Mercer kernel Hilbert space with Bernstein-Durrmeyer operators. We first give estimates of l2- norm of Mercer kernel matrices reproducing by the kernelsK(α,β)(x,y):=∑∞k=0 Ck(α,β)(x)Qk(α,β)(y),where Qk(α,β) (x) are the Jacobi polynomials of order k on (0, 1 ), Ck(α,β) 〉 0 are real numbers, and from which give the lower and upper bounds of the covering number for some particular reproducing kernel Hilbert space reproduced by Kα,β (x, y). 展开更多
关键词 Mercer kernel matrix covering number Bernstein-Durrmeyer operator
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Normality Criteria for Families of Holomorphic Functions 被引量:2
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作者 王建平 《Northeastern Mathematical Journal》 CSCD 2003年第3期267-272,共6页
Let f be a holomorphic function on a domain D (?) C, and let a be a finite complex number. We denote by Ef(α) = {z∈ D : f(z) = a, ignoring multiplicity} the set of all distinct α-points of f. Let F be a family of h... Let f be a holomorphic function on a domain D (?) C, and let a be a finite complex number. We denote by Ef(α) = {z∈ D : f(z) = a, ignoring multiplicity} the set of all distinct α-points of f. Let F be a family of holomorphic functions on D. If there exist three finite values a, b(≠ 0, a) and c(≠0) such that for every f ∈ F, Ef(0) (?) Ef'(a) and Ef'(b)(?) Ef(c), then F is a normal family on D. 展开更多
关键词 meromorphic function holomorphic function normal family
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Effects of Subchronic Samarium Exposure on Testicle Tissue of Mice
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作者 Can Yaping Shen Xiuying +1 位作者 Xu Xiaolu Chen Yongyi 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第2期I0002-I0002,共1页
To study the toxicity of samarium nitrate on male mice's testicle tissue, samarium nitrate was administrated to mice at different doses(0, 5, 50, 500, 2000 mg·L^-1) for 3 months. The biochemical index and path... To study the toxicity of samarium nitrate on male mice's testicle tissue, samarium nitrate was administrated to mice at different doses(0, 5, 50, 500, 2000 mg·L^-1) for 3 months. The biochemical index and pathological changes were observed. The results show that the construction of testicle, especially in sperms and testis intersitium are broken. LDH enzyme activity in 2000 mg·L^-1 and LDH-X enzyme activity in 500 and 2000 mg·L^- 1dose groups are inhibited obviously. SDH enzyme activity in 50, 500 and 2000 mg·L^-1 dose groups are lower than that in control group, but T-GT enzyme activity is unacted on Sm. With increase of samarium concentration, Na^+K^+-ATP, Mg^2+-ATP enzyme activity tend to "promote weakly and inhibited strongly", while Ca^2+-ATPase decrease largely. Subchronic samarium exposure has definite toxicity to gonad of mice. 展开更多
关键词 SAMARIUM MICE TESTIS biochemical index HISTOPATHOLOGY rare reaths
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UNIQUENESS OF DIFFERENCE POLYNOMIALS OF MEROMORPHIC FUNCTIONS
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作者 刘永 祁晓光 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期444-452,共9页
In this article, we investigate the uniqueness problems of difference polynomials of meromorphic functions and obtain some results which can be viewed as discrete analogues of the results given by Shibazaki. Some exam... In this article, we investigate the uniqueness problems of difference polynomials of meromorphic functions and obtain some results which can be viewed as discrete analogues of the results given by Shibazaki. Some examples are given to show the results in this article are best possible. 展开更多
关键词 Meromorphic functions difference polynomials UNIQUENESS finite order
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Optically induced phase transition of excitons in coupled quantum dots
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作者 陈子栋 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期1084-1087,共4页
The weak classical light excitations in many semiconductor quantum dots have been chosen as important solid- state quantum systems for processing quantum information and implementing quantum computing. For strong clas... The weak classical light excitations in many semiconductor quantum dots have been chosen as important solid- state quantum systems for processing quantum information and implementing quantum computing. For strong classical light we predict theoretically a novel phase transition as a function of magnitude of this classical light from the deformed to the normal phases in resonance ease, and the essential features of criticality such as the scaling behaviour, critical exponent and universality are also present in this paper. 展开更多
关键词 phase transition UNIVERSALITY excitation in quantum dot
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Peculiar Quantum Phase Transitions and Hidden Supersymmetry in a Lipkin-Meshkov-Glick Model
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作者 CHEN Gang LIANG Jiu-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第5期881-884,共4页
In this paper we theoretically report an unconventional quantum phase transition of a simple Lipkin- Meshkow-Glick model: an interacting collective spin system without external magnetic field. It is shown that this m... In this paper we theoretically report an unconventional quantum phase transition of a simple Lipkin- Meshkow-Glick model: an interacting collective spin system without external magnetic field. It is shown that this model with integer-spin can exhibit a flrst-order quantum phase transition between different disordered phases, and more intriguingly, possesses a hidden supersymmetry at the critical point. However, for half-integer spin we predict another flrst-order quantum phase transition between two different long-range-ordered phases with a vanishing energy gap, which is induced by the destructive topological quantum interference between the intanton and anti-instanton tunneling paths and accompanies spontaneously breaking of supersymmetry at the same critical point. We also show that, when the total spin-value varies from half-integer to integer this model can exhibit an abrupt variation of Berry phase from π to zero. 展开更多
关键词 Lipkin-Meshkov-Glick model quantum phase transition supersylnmetry
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