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Zhang M.-C.,Shaanxi Normal University | Huang-Fu G.-Q.,Weinan Normal University
Annals of Physics | Year: 2012

An anharmonic oscillatory potential is proposed in which a noncentral electric dipole is included. The pseudospin symmetry for this potential is investigated by working in a complete square integrable basis that supports a tridiagonal matrix representation of the wave operator. The resulting three-term recursion relation for the expansion coefficients of the wavefunctions (both angular and radial) are presented. The angular/radial wavefunction is written in terms of Jacobi/Laguerre polynomials. The discrete spectrum of the bound states is obtained by the diagonalization of the radial recursion relation. The algebraic properties of the energy equation are also discussed, showing the exact pseudospin symmetry. © 2011 Elsevier Inc.

Duan B.R.,Yantai University | Duan B.R.,Shanxi University | Cao Q.,Weinan Normal University
Electrochimica Acta | Year: 2012

Hierarchically porous Co 3O 4 film is prepared via a hydrothermal synthesis method based on a self-assembled monolayer polystyrene (PS) spheres template. The as-prepared Co 3O 4 film shows a two-layer structure: substructure is composed of Co 3O 4 monolayer hollow-sphere array and the superstructure consists of porous net-like Co 3O 4 nanoflakes possessing continuous mesopores ranging from 2 to 5 nm. The pseudocapacitive behavior of the hierarchically porous Co 3O 4 film is investigated by cyclic voltammograms (CV) and galvanostatic charge-discharge tests in 2 M KOH. As cathode material for supercapacitors, the hierarchically porous Co 3O 4 film exhibits noticeable pseudocapacitive properties with a capacitance of 454 F g -1 at 2 A g -1 as well as quite good cycling stability and high capacitance retention. Compared to the film prepared without template, the hierarchically porous film exhibits weaker polarization, higher capacitances and better cycling performance. The enhancement of pseudocapacitive properties are due to the hierarchically porous architecture, which provides fast ion/electron transfer and alleviates the structure degradation caused by volume expansion during the cycling process. © 2012 Elsevier Ltd. All rights reserved.

Guofu Y.,Weinan Normal University
International Journal of Advancements in Computing Technology | Year: 2012

This paper proposes a novel optimization algorithm combined the mechanism of quantum evolutionary algorithm and real-coding method, called an improved quantum particle swarm optimization algorithm (IQPSO). Like the traditional particle swarm optimization, IQPSO is also characterized by position vector and velocity vector to implement the evolution process. However, the particle of IQPSO is divided into two parts. The first part is real-valued coding; and the rest of it is quantum probability amplitude. Further, IQPSO uses quantum probability amplitude as velocity vector, and a Q-gate is applied to update the quantum probability amplitude. At the same time, a self adaptable mutation operator is used to improve the diversity of population. To demonstrate the effectiveness of IQPSO, experiments are carried out on the function optimization; and the results show that IQPSO performs well.

Xi C.,Weinan Normal University
Physica B: Condensed Matter | Year: 2013

We design and study a kind of gammadion-like chiral metamaterial (CMM), which uniaxially exhibits exceedingly strong optical activity and circular dichroism. The optical activity obtained by the proposed CMM rises to about 2280 /λ, which is much larger than that of the previously reported planar designs. Due to the giant chirality, the present CMM can realize negative refractive index easily at the resonant frequencies. The most fascinating property of the present CMM is that it can function as a 90 polarization rotator for wide incident angles, thereby holding great promise for future devices. © 2013 Elsevier B.V.

Li Y.,Weinan Normal University
International Journal of Polymeric Materials and Polymeric Biomaterials | Year: 2012

In this study, the influence of coupling agent concentration (0 and 3wt%), wood fiber content (50, 60, 70, and 80wt%), and size (40-60, 80-100, and 160-180 mesh) on the mechanical properties of wood/high-density-polyethylene (HDPE) composites (WPCs) was investigated. WPC samples were prepared with poplar wood-flour, HDPE, and polyethylene maleic anhydride copolymer (MAPE) as coupling agent. It was found that the tensile properties and the flexural properties of the composites were improved by the addition of 3wt% MAPE, and the improved interfacial adhesion was well confirmed by SEM micrographs. It was also observed that the best mechanical properties of wood/HDPE composites can be reached with larger particle size in the range studied, while too-small particle size was adverse for the mechanical properties of wood/HDPE composites. Moreover, the tensile modulus, tensile strength, and flexural strength of WPCs decreased with the increase in fiber content from 50 to 80wt%; the flexural modulus of WPCs increased with the increase in fiber content from 50 to 70wt% and then decreased as the fiber content reached 80wt%. The variances in property performance are helpful for the end-user to choose an appropriate coupling agent (MAPE) concentration, wood fiber content, and particle size based on performance needs and cost considerations. © 2012 Taylor and Francis Group, LLC.

Li Y.,Weinan Normal University
International Journal of Adhesion and Adhesives | Year: 2014

The acetylation of eucalyptus wood fibers (WFs) was conducted in 50%/50% (v/v) of acetic acid and acetic anhydride catalyzed by sulfuric acid at 60 C for 2 h. Twenty one percent weight percent gain (WPG) level was achieved. Then the contact angles of three probe liquids on the surface of unacetylated and acetylated eucalyptus WFs were tested by the capillary rise method, and the surface free energies of unacetylated and acetylated eucalyptus WFs and their dispersion and polar components were calculated according to the method suggested by Owens-Wendt-Kaelble. The results show that the surface free energy of unacetylated eucalyptus WFs is 24.7 mJ/m2, and its corresponding dispersion and polar components are 14.8 mJ/m2 and 9.9 mJ/m 2, respectively. However, the surface free energy of acetylated eucalyptus WFs is 38.3 mJ/m2 which is higher than the surface free energy of PP (29.4 mJ/m2), and its corresponding dispersion and polar components are 35.6 mJ/m2 and 2.7 mJ/m2, respectively. So it is possible for the spreading of PP on the surface of acetylated eucalyptus WFs and forming a good interfacial adhesion between acetylated eucalyptus WFs and PP. The better interfacial compatibility between acetylated eucalyptus WFs and PP was corroborated by the scanning electron microscopy (SEM) micrographs. © 2014 Elsevier Ltd.

The objective of this study was to investigate the incorporation of poplar wood fibers both with and without a novel coupling agent, alkyl ketene dimer (AKD), on the mechanical properties of wood fiber/polypropylene (PP) composites. The resulting properties were compared to those obtained with the most commonly used coupling agent, maleic anhydride grafted PP (MAPP). Tensile and impact strengths of the composites decreased with increasing poplar wood fibers content. Tensile modulus of the composites increased by the incorporation of the wood fibers content up to 70. wt% but further increment in the wood fibers decreased the tensile modulus. At the constant content of poplar wood fibers (70. wt%), the tensile strength determined for the coupled composites with 5% AKD increased by 41% in comparison with the non-coupled composites while the tensile modulus increased by 45%, the impact strength of the coupled composites increased by 38%. The performance of 5% AKD on the mechanical properties of the composites is a little better than 3% MAPP. The good performance of 5% AKD is attributed to the enhanced compatibility between the poplar wood fibers and the polymer matrix. The increase in mechanical properties of the composites demonstrated that AKD is an effective coupling agent for wood fiber/PP composites. © 2014 Elsevier Ltd.

Wang J.-X.,Weinan Normal University
Guangzi Xuebao/Acta Photonica Sinica | Year: 2014

The atom fidelity and degree of entanglement were calculated in the system consisting of M two-level atoms and M multi-mode fields by use of complete quantum theory and number computing method. Through number computing and analyzing, it was found that the atom fidelity and the atom entangled degree present always oscillatory with opposite in phase if initial atoms are in separate state, and both of their frequency gradually increase with the intensity of light field increasing. The atom fidelity tends to 0 and degree of entanglement tends to 1 under strongly coupling between atoms and light fields. The small fidelity is disadvantage of information transfer but high-fidelity atom information transfer can still obtained by controlling appropriately interaction time.

Zhang H.,Weinan Normal University
Energy Procedia | Year: 2011

With an escalating conflict between economic growth and environment, eco-industrial parks' evaluation gradually becomes a hot topic in the academic field. On the basis of previous research, this article built up the evaluation index system of the Eco-Industrial Parks, Then evaluated the project by using the fuzzy analytic hierarchy integrated evaluation method. © 2011 Published by Elsevier Ltd.

Cao Q.,Weinan Normal University
Journal of Molecular Modeling | Year: 2013

Dinitroamino benzene derivatives are designed and studied in detail with quantum chemistry method. The molecular theory density, heats of formation, bond dissociation energies, impact sensitive and detonation performance are investigated at DFT-B3LYP/6-311G**level. The results of detonation performance indicated most of the compounds have better detonation velocity and pressure than RDX and HMX. The N-N bond can be regard as the trigger bond in explosive reaction, and the bond dissociation energies of trigger bond are almost not affected by the position and number of substituent group. The impact sensitive are calculated by two different theory methods. It is found that the compounds, which can become candidates of high energy materials, have smaller H50 values than RDX and HMX. It is hoped that this work can provide some basis information for further theory and experiment studies of benzene derivatives. © 2013 Springer-Verlag Berlin Heidelberg.

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