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Synthesis and spectroscopic characterization of fluorescent solid rare-earth complexes with hydroxamic acids

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Rare Metals 2002年第3期21卷 163-169页

作者： LI Yangsheng and LI FanFaculty of Chemistry and Materials Science, nanchang university, nanchang 200437, China Faculty of Chemistry and Materials Science Nanchang University Nanchang 330047

The complexes RE_2(DHYA)_3 centre dot nH_2O in the title bar were synthesizedthrough some reactions of trivalent rare-earth ions. In the process of synthesis, dihydroxamicacids were taken as ligands while the alcohol was taken as a solvent. The ligands includedadipylhydroxamic acid (ADHA), p-phthalichydroxamic acid (PPHA), oxalohydroxamic acid (OXHA),butadihydroxamic acid (BDHA), o-phthalichydroxamic acid (OPHA), benzoylhydroxamic acid (BHA), *** at 25 deg C, the molar conductances in various modes are 13.00-21.05 S centre dot cm^2centre dot mol^(-1), which shows that rare-earth complexes are nonelectrolytes and the hydroxaminogroups of the complexes have taken part in bonding. Infrared spectra, ultraviolet spectra, nuclearmagnetic resonance (~1HNMR) spectra, and fluorescence spectra were used to investigate thecomplexes. Experiments have proved that the complexes of En^(3+)and Tb^(3+) with aromatic hydroxamicacids have good fluorescent characteristics.

关键词： hydroxamic acid complex rare earth

Optimized third-order force-gradient symplectic algorithms

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Science China(Physics,Mechanics & Astronomy) 2010年第9期53卷 1600-1609页

作者： LI Rong & WU Xin School of Science,nanchang university,nanchang 330031,China School of Science Nanchang University Nanchang China

With the natural splitting of a Hamiltonian system into kinetic energy and potential energy,we construct two new optimal thirdorder force-gradient symplectic algorithms in each of which the norm of fourth-order truncation errors is *** are both not explicitly superior to their no-optimal counterparts in the numerical stability and the topology structure-preserving,but they are in the accuracy of energy on classical problems and in one of the energy eigenvalues for one-dimensional time-independent Schrdinger *** particular,they are much better than the optimal third-order non-gradient symplectic *** also have an advantage over the fourth-order non-gradient symplectic integrator.

关键词： symplectic integrators symplectic scheme-shooting method celestial mechanics time-independent Schrdinger equation energy eigenvalues numerical stability bisection method topological structure

New concurrent digital signature scheme based on the computational Diffie-Hellman problem

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The Journal of China Universities of Posts and Telecommunications 2010年第6期17卷 89-94,100页

作者： QIN Wen,ZHOU Nan-run Department of Electronic Information Engineering,nanchang university,nanchang 330031,China Department of Electronic Information Engineering Nanchang University Nanchang 330031 China

Based on strong designated verifiers signatures,a new fair concurrent signature scheme is proposed. Compared with the previous concurrent signature schemes,even if a keystone must be chosen by the initial signer,the matching signer will easily get the keystone through an extraction algorithm. Due to the property of strong designate verifying,the initial signer couldn＇t make use of the keystone prepared carefully to deceive the matching signer. Then the matching signer is able to participate actively the signature scheme. Besides,there aren＇t bilinear operations in the keystone algorithm to deliver the keystone efficiently. Therefore the efficiency of our signature scheme is also improved.

关键词： designated verifiers signature fairness concurrent signature information security

A NEW TURBULENCE MODULATION IN SECOND-ORDER MOMENT TWO-PHASE MODEL AND ITS APPLICATION TO HORIZONTAL CHANNEL

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Journal of Hydrodynamics 2008年第3期20卷 331-338页

作者： ZENG Zhuo-xiong Aeronautic and Mechanical Engineering College Nanchang Hangkong University Nanchang 330063 China

A new second-order moment two- phase turbulence model accounting for particle wake effect was established and used to simulate gas-particle flow in a horizontal channel for different values of wall roughness. The results show that compared with the model without considering the particle wake effect, the present model gives simulation results agreeing much better with the experimental results for the gas turbulence modulation, but the predicted results for particle motion with the two kinds of models are quite close.

关键词： gas-particle flows turbulence modification numerical simulation

SECOND-ORDER MOMENT TWO-PHASE TURBULENCE MODEL ACCOUNTING FOR TURBULENCE MODULATION IN SWIRLING SUDDEN-EXPANSION CHAMBER

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Journal of Hydrodynamics 2008年第1期20卷 54-59页

作者： ZENG Zhuo-xiong Aeronautic and Mechanical Engineering College Nanchang Hangkong University Nanchang 330063 China

A semi-empirical turbulence enhancement model accounting for the particle-wake effect was incorporated into the second-order moment two-phase turbulence model and employed to simulate gas-particle flows in a swirling sudden-expansion chamber. The simulated results for two-phases mean velocities and fluctuation velocities coincide well with the experiment ones, which demonstrates that this model, in comparison with the turbulence model not accounting for the wake effect, leads to higher calculating accuracy.

关键词： gas-particle flows turbulence modulation particle wake effect

A SECOND-ORDER MOMENT TURBULENCE MODEL FOR POWER LAW FLUID WITH PARTICLES

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Journal of Hydrodynamics 2007年第5期19卷 607-612页

作者： ZENG Zhuo-xiong PAN Yang ZHONG Chun QIU Guo-bin Aeronautic and Mechanical Engineering College Nanchang Hangkong University Nanchang 330063 China School of Civil Engineering and Architecture East China Jiaotong University Nanchang 330013 China

The USM-θ model of power law fluid for dense two-phase turbulent flow was developed, which combines the unified second-order moment model for two-phase turbulence with the particle kinetic theory for the inter-particle collision. This model was used to simulate the turbulent flow of power law fluid single-phase in pipe. It is shown that the USM- θ model has better prediction result than the κf -κf - κ- εp -θ model. The USM-O model was then used to simulate the dense two-phase turbulent up flow of power law fluid with particles. With the increase of the flow exponent, the velocities of power law fluid and particles increase near the pipe centre. Comparison between the two-phase flow of power law fluid-particle and of liquid-particle indicates that the axial fluctuation velocity of fluid phase and particle phase in liquid-particle two-phase flow is smaller than that in the power law fluid two-phase flow, but the two-phase velocities of power law fluid-particle and liquid-particle are close to each other.

关键词： power law fluid two-phase flow second-ordermoment turbulence model

Empirical study on entropy models of cellular manufacturing systems

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Progress in Natural Science:Materials International 2009年第3期19卷 389-395页

作者： Zhifeng Zhang a,b,*, Renbin Xiao a a CAD Center, Huazhong university of Science and Technology, Wuhan 430074, China b Economics and Management School of nanchang, Hangkong university, nanchang 330063, China CAD Center Huazhong University of Science and Technology Wuhan 430074 China Economics and Management School of nanchang Hangkong University Nanchang 330063 China

From the theoretical point of view, the states of manufacturing resources can be monitored and assessed through the amount of infor- mation needed to describe their technological structure and operational state. The amount of information needed to describe cellular manufacturing systems is investigated by two measures: the structural entropy and the operational entropy. Based on the Shannon entropy, the models of the structural entropy and the operational entropy of cellular manufacturing systems are developed, and the cog- nizance of the states of manufacturing resources is also illustrated. Scheduling is introduced to measure the entropy models of cellular manufacturing systems, and the feasible concepts of maximum schedule horizon and schedule adherence are advanced to quantitatively evaluate the effectiveness of schedules. Finally, an example is used to demonstrate the validity of the proposed methodology.

关键词： Cellular manufacturing systems Structural entropy Operational entropy Scheduling

PRE-IMAGE ENTROPY OF NONAUTONOMOUS DYNAMICAL SYSTEMS

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Journal of Systems Science & Complexity 2008年第3期21卷 441-445页

作者： Xianjiu HUANG Xi WEN Fanping ZENG Department of Mathematics Nanchang University Nanchang 330031 China Department of Computer Nanchang University Nanchang 330031 China Department of Mathematics Liuzhou Theachers College Liuzhou 545004 China

The authors define and study topological pre-image entropy for the non-autonomous discrete dynamical systems given by a sequence {fi}i=1^∞ of continuous self-maps of a compact topological space. The basic properties and the invariant with respect to equiconjugacy of pre-image entropy for the non-autonomous discrete dynamical systems are obtained.

关键词： Equiconjugacy non-autonomous pre-image entropy sequence of continuous self-maps

Phosphorus forms and distribution in the sediments of Poyang Lake,China

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International Journal of Sediment Research 2011年第2期26卷 230-238页

作者： XIANG Su-lin and ZHOU Wen-bin 1 Lecturer,Key Lab of Poyang Lake Ecology and Bio-resource Utilization,Ministry of Education,nanchang university,nanchang 330047,China and Department of Environmental Engineering,East China JiaoTong university,nanchang 330013,China, 2 Prof,Key Lab of Poyang Lake Ecology and Bio-resource Utilization,Ministry of Education,nanchang university,nanchang 330047,China Lecturer Key Lab of Poyang Lake Ecology and Bio-resource Utilization Ministry of Education Nanchang University Nanchang 330047 China and Department of Environmental Engineering East China JiaoTong University Nanchang 330013 China Prof. Key Lab of Poyang Lake Ecology and Bio-resource Utilization Ministry of Education Nanchang University Nanchang 330047 China

The forms and distribution of phosphorus in the sediments of Poyang Lake were studied using chemical extraction methods to understand the potential release and adsorption of *** results showed that phosphorus in the sediments mainly consisted of inorganic phosphorous species, including iron bound phosphorus,calcium bound phosphorus,aluminium bound phosphorus and dissolved phosphorus,as well as organic phosphorous *** spatial distribution of phosphorus species in surface sediments showed a decreasing trend from the outlet to the entrance of Poyang *** content of total phosphorus in the surface sediments ranged from 688.29 to 825.36 mg/kg, and inorganic phosphorous was the major phosphorus *** bound phosphorus was the dominant form of inorganic phosphorous,accounting for greater than 40%of the total phosphorus, while calcium bound phosphorus and aluminium bound phosphorus accounted for more than 20%, and dissolved phosphorus accounted for less than 5%.The content of organic phosphorus in surface sediments was lower,accounting for less than 15%.Total phosphorus was positively correlated with iron bound phosphorus,aluminium bound phosphorus,calcium bound phosphorus and organic phosphorous,while organic phosphorous was positively correlated with iron bound phosphorus and aluminium bound phosphorus,but only weakly related to calcium bound *** all six sites, the contents of total phosphorus and phosphorus forms in the core sediments obviously decreased with depth,while they were significantly enriched in the surface *** total phosphorus and phosphorus forms contents were significantly higher in the upper layers and had a tendency to decrease toward the bottom of the core,regardless of the phosphorus *** addition,the average contents of total phosphorus and various phosphorus forms decreased rapidly with sediment depth from 0-20 cm,and then decreased slightly from 20-30 cm.

关键词： Poyang Lake Phosphorus forms Distribution characteristics Sediment