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An algebraic invariant for Jordan automorphisms on B(H):The set of idempotents

International technology and Innovation Conference 2006

作者： LEI Weining LI Renxing SHEN Laidi Institute of Mechanical & Electrical Engineering jiangshu teachers university of technology Changzhou 213001 China

＜正＞Electroforming is the precision manufacturing process in which a metallic part is produced in an electrolytic bath by the electrodeposition of metal onto a cathode mandrel. Improvement of the electrodeposit properties has been paid to considerable attention during the last decade. In this paper, a new method was developed to synthesize bulk nanocrystalline（NC） nickel. The high frequency pulse current and high deposit current density were employed to increase the deposit cathodic overpotential and the nucleation rate. With increasing peak current density, the deposit grain sizes was decreased markedly, e.g. average grain sizes ranging from 200 nm to 50 nm were determined when the peak current density varied from 60 A dm-2 to 300 A dm-2 at the on-time of 10 μs and the off-time of 90 μs. The effect of the grain sizes on the mechanical properties was discussed for room and a medium temperature. It was found that the properties of the electrodeposited nickel such as micro-hardness, yield stress （at room temperature and 473 K） were improved substantially with the decrease in the grain size. A deviation of yield stress from Hall-Petch relationship for nc nickel was observed when the grain sizes were decreased to less than 70 nm at room temperature. A low yield stress value of nc nickel was obtained at a temperature of 673 K as a result of its thermodynamic instability.

关键词： Nanocrystalline pulse electrodeposition electrodeposit mechanical properties.

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Science China Mathematics 2005年第12期48卷 1585-1596页

作者： CUI Jianlian & HOU Jinchuan Department of Mathematical Science, Tsinghua university, Beijing 100084, China Department of Applied Mathematics, Taiyuan university of technology, Taiyuan 030024, China Department of Mathematics, Shanxi teachers university, Linfen 041004, China Department of Mathematical Science Tsinghua University Beijing 100084 China Department of Applied Mathematics Taiyuan University of Technology Taiyuan 030024 China Department of Mathematics Shanxi Teachers University Linfen 041004 China

Let H be an infinite dimensional complex Hilbert space. Denote by B(H) the algebra of all bounded linear operators on H, and by I(H) the set of all idempo-tents in B(H). Suppose that Φ is a surjective map from B(H) onto itself. If for every λ ∈ {-1,1,2,3,1/2,1/3} and A, B ∈ B(H), A - λB ∈ I(H) (?) Φ(A) - λΦ(B) ∈ I(H), then Φ is a Jordan ring automorphism, i.e. there exists a continuous invertible linear or conjugate linear operator T on H such that Φ(A) = TAT-1 for all A ∈ B(H), or Φ(A) = TA*T-1 for all A ∈ B(H); if, in addition, A-iB ∈ I(H) (?) Φ(A) -ιΦ(B) ∈ I(H), here ι is the imaginary unit, then Φ is either an automorphism or an anti-automorphism.

关键词： Hilbert space operators,Jordan automorphisms,idempotents.

ON THE LINEAR APPROXIMATION OPERATOR WHICH HAS ALGEBRAIC PRECISION OF POINTED ORDER

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Analysis in Theory and Applications 1993年第3期9卷 89-95页

作者： Di Jizheng (Shanxi teachers’ university,China) Department of Mathematics Shanxi Teachers’ University Linfen Shanxi PRC

In this paper,we construct an operator which has algebraic precision of pointed order and approximates to fC[0,1]uniformly on[0,1].

关键词： Linear Operator Linear Approximation Rational Fraction Type Operator Definite Answer

Decentralized H-infinity state feedback control for discrete-time singular large-scale systems

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控制理论与应用（英文版） 2010年第2期8卷 200-204页

作者： Songlin WO 1 , Yun ZOU 2 , Shengyuan XU 2 (1.School of Electrical and Information Engineering, Jiangsu teachers university of technology, Changzhou Jiangsu 213001, China 2.School of Automation, Nanjing university of Science and technology, Nanjing Jiangsu 210094, China) School of Electrical and Information Engineering Jiangsu Teachers University of Technology Changzhou Jiangsu China School of Automation Nanjing University of Science and Technology Nanjing Jiangsu China

The decentralized H-infinity control problem for discrete-time singular large-scale systems is considered. Based on the bounded real lemma of discrete-time singular systems, a sufficient condition for the existence of decentralized H-infinity controller for discrete-time singular large-scale systems is presented in terms of the solvability to a certain system of linear matrix inequalities by linear matrix inequality (LMI) approach, and the feasible solutions to the system of LMIs provide a parameterized representation of a set of decentralized H-infinity controller. The given example shows the application of the method.

关键词： Discrete-time singular large-scale system Linear matrix inequality (LMI) Decentralized H-infinity control

Internal noise stochastic resonance in CO oxidation on nm-sized palladium particles

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Science China Chemistry 2005年第5期48卷 395-401页

作者： GONG Yubing1,2, HOU Zhonghuai1 & XIN Houwen1 1. Department of Chemical Physics, university of Science and technology of China, Hefei 230026, China 2. Department of Physics, Yantai teachers university, Yantai 264025, China Department of Chemical Physics University of Science and Technology of China Hefei China Department of Physics Yantai Teachers University Yantai China

Based on a stochastic mesoscopic model, the influence of internal noise on the oscillatory kinetics of the catalytic oxidation of CO on nm-sized palladium particles is studied, using the chemical Langevin equations, Poisson approximation algorithm, and exact stochastic simulation algorithm. The reaction rate oscillations are of stochastic nature due to considerable internal noise in such mesoscopic systems. It is found that the performance of the stochastic oscillations undergoes a maximum with the variation of internal noise level for a given CO partial pressure, which demonstrates the occurrence of internal noise stochastic resonance. This phe-nomenon implies that optimal internal noise would favor the reaction rate oscillation of CO oxi-dation on nm particles. Such a phenomenon is robust to the change of external parameters, such as CO pressures.

关键词： nanometer-sized palladium particles, surface catalytic CO oxidation, internal noise, stochastic resonance, chemical Langevin equation.

Stochastic resonance in surface catalytic oxidation of carbon monoxide induced by colored noise

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Science China Chemistry 2004年第2期47卷 106-112页

The dynamical behavior of surface catalytic oxidation reaction of Pt(110)/CO+O2 modulated by colored noise, under the condition of specific temperature, has been investigated when the partial pressure of CO gas is near the supercritical Hopf bifurcation point. By computer simulation the oscillation and stochastic resonance induced by colored noise are observed. The influences of the intensity and correlation time of colored noise on stochastic resonance are discussed. The range of sensitivity of the system to the environmental fluctuation is analyzed.

关键词： colored noise, stochastic resonance, surface catalytic reaction of Pt(110)/CO+O2, supercritical Hopf bifurcation, signal-to-noise ratio (SNR).

Controllability for a Class of Singular Systems

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Controllability for a Class of Singular Systems

A Facile Synthesis of Cerium Phosphate Nanofiber by Solution-solid Method

第三十届中国控制会议

作者： WANG jiangshu,LIU Feng School of Mathematics and Physics,Jiangsu teachers university of technology,Changzhou 213001,P.R.China

＜正＞Controllability is a basic problem of modern control *** of singular system is one of difficult *** intrigued many of expert and *** this paper,suppose that the system is regular,branch the system into two subsystems of quick and slow,discuss their *** necessary and sufficient conditions concerning the controllability of singular systems are given by a *** an illustrative example is given.

关键词： Singular systems Controllability Modulus of impulse

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Journal of Materials Science & technology 2010年第1期26卷 45-48页

作者： Mingyun Guan, Jianhua Sun,Tongming Shang, Quanfa Zhou,Jianting Han and Aiqin Ji Jiangsu Key Laboratory of Precious Metals Chemistry, School of Chemistry and Engineering, Jiangsu teachers university of technology, Changzhou 213001, China Jiangsu Key Laboratory of Precious Metals Chemistry School of Chemistry and Engineering Jiangsu Teachers University of Technology

A solution-solid method is developed to construct cerium phosphate （CePO4） nanofibers. Tetraphosphoric acid formed the condensed linear polyphosphate （PnO3n＋1）^（n＋2）- before reacting with cerium carbonate （Ce2（CO3）3） powder, which was favourable for one dimensional CePO4 nanofibers forming. The growth mechanism was proposed based on solution-solid process. CePOa nanofibers display strong UV luminescence emission and weak blue emission.

关键词： Cerium phosphate Nanofiber Nanostructure Solution-solid method

Electronic Structure of New Superconducting Perovskite MgCNi3

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Journal of Materials Science & technology 2004年第2期20卷 203-205页

作者： Li CHEN, Hua LI and Liangmo MEIPhysics and Microelectronic School, Shandong university, Jinan 250100, China Department of Physics, Linyi teachers university, Shandong 276005, China Phys. and Microelectron. Sch. Shandong Univ. Ji'nan 250100 China Dept. of Phys. Linyi Teachers Univ. Linyi 276005 China

The electronic structures of new superconducting perovskite MgCNi3 and related compounds MgCNi2T (T=Co, Fe, and Cu) have been studied using MS-Xa method. In MgCNi3, the main peak of density of states is located below the Fermi level and dominated by Ni d. From the results of total energy calculations, it was found that the number of Ni valence electron decreases faster for the Fe-doped case than that for the Co-doped case. The valence state of Ni changes from +1.43 in MgCNi2Co to +3.02 in MgCNi2Fe. It was confirmed that Co and Fe dopants in MgCNi3 behave as a source of d-band holes and the suppression of superconductivity occurs faster for the Fe-doped case than that for the Co-doped case. In order to explain the fact that Co and Fe dopants in MgCNi3 behave as a source of d-band holes rather than magnetic scattering centers that quench superconductivity, we have also investigated the effects of electron (Cu) doping on the superconductivity and found that both electron (Cu) doping and hole (Co, Fe) doping quench superconductivity exist. Comparing with the hole (Co) doping, there was no much difference between Cu and Co doping. This suggests that Co and Fe doping do not act as magnetic impurity.

关键词： Electronic structure Superconductivity Density of states