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ISSN 1674-2850
CN 11-9150/N5
 
Current Issue
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April 15,2016
Volume 9,Issue 7
Pages -
Subject Area:Catalytic Chemistry,Analytical Chemistry,Basic Mechanics,Fluid Mechanics,Applied Mathematics,Computational Mathematics,Dynamical System,Functional Analysis
 
Title: Prepration of pyrazolone/gelatin-xanthan gum composite films and its photochromic properties
Authors: WEI Chuanbo, GUO Jixi, GUO Mingxi, JIA Dianzeng
PP: 753-758
Abstract: Novel photochromic composite films have been successfully fabricated using solid dispersion method, using gelatin-xanthan gum as substrates. The microstructure and photochromic properties of composite films were investigated by scanning electron microscope (SEM), ultraviolet-visible spectroscopy (UV-vis), fluorescence emission spectroscopy (FL) and confocal microscope Raman spectroscopy. The results showed that the organic photochromic materials can be well and uniformly dispersed into gelatin-xanthan gum sunstrate in a micron sized particle way and the photochromic phenomenon is almost not disturbed by polymer matrix.
Keywords: photochemistry; photochromism; pyrazolone; gelatin-xanthan gum; composite film
 
Title: Hydrogenation of succinic acid to γ-butyrolactone over Pd/TiO2 catalysts
Authors: YOU Chenjia, CHEN Lifang, QI Zhiwen
PP: 746-752
Abstract: In this paper, anatase TiO2 nanosheets were synthesized by solvothermal method and then highly dispersed palladium nanoparticles were loaded on the TiO2 support (Pd/TiO2) by the deposition-precipitation method. The characterization results reveal that Pd particles are highly dispersed onto the surface of TiO2 nanosheets with average size of 1.9 nm. The Pd/TiO2 catalysts were used for the selective hydrogenation of succinic acid (SUC) to γ-butyrolactone (GBL) and the calcination temperature of TiO2 and reaction time were also investigated. Pd/TiO2 (400) is an efficient catalyst for the hydrogenation of SUC to GBL, which exhibits 90% SUC conversion, 94% selectivity to GBL and 85% yield for GBL at 200℃ and 107 Pa H2 for 8 h using water as green solvent.
Keywords: catalysis chemistry; succinic acid hydrogenation; Pd nanoparticles; TiO2; γ-butyrolactone
 
Title: Preparation of Ag(I) surface imprinted polymer with nano-titanium dioxide as supporter and its applications
Authors: LIU Yanxiong, LIU Xiaolan, TAN Wenxiang, LIU Peng, CAO Qiue
PP: 739-745
Abstract: Based on the soft and hard acid and alkali theory, N-allylthiourea (NAU), which can use N as coordination atom, was selected as functional monomer for the preparation of Ag(I) ion-imprinted polymer (IIP). After the amounts of functional monomer, cross-linking agent and nano-titanium dioxide were optimized, a Ag(I) ion-imprinted polymer was obtained by surface imprinting technique with 0.1 mmol Ag(I) as template, 0.3 mmol NAU as functional monomer, 50 mg nano-titanium dioxide as supporter, and 3 mmol ethylene glycol dimethacrylate (EGDMA) as crosslinker. The adsorption capacity and imprinting factor of this IIP in 10 mL of aqueous solutions containing 50 mg/L Ag(I) were 34.16 mg/g and 1.94, respectively. The obtained IIP could be used as adsorbent for solid phase extraction of Ag(I). After the extraction conditions was optimized, the solid phase extraction based Ag(I) ion-imprinted polymers exhibited good selectivity to Ag(I) over the other metals such as Ir(IV)、Pd(II)、Ru(III)、Rh(III)、Au(III) and Cu(II). The extraction percentage for Ag(I) could reach to above 78% and those for the other metals were below 15%.
Keywords: analytical chemistry; Ag(I); ion-imprinted polymer; surface imprinting technique; nano-titanium dioxide; solid phase extraction
 
Title: Fluidization of LiF powders with additive particles
Authors: XIA Wei, ZHONG Huangliang, YANG Xiushan, KONG Xingjian, ZHANG Zhiye, WANG Xinlong
PP: 731-738
Abstract: Considering the particle characteristic of LiF, this paper proposed a method to improve the fluidization quality of LiF powders through adding the coarse particle. Experiment investigation on the fluidization characteristic of LiF powders by adding different barite sands (particles sizes were 150-180 μm, 180-250 μm and 250-380 μm; weight ratio were 30%, 50%, 60% and 70%) was conducted in the self-build fluidized bed equipment. The results showed that single component LiF powders (average particle diameter 16 μm) couldn’t achieve good dispersion fluidization effects, and the phenomenon of plunger, channeling and agglomeration would easily occur in the reaction process. However, single component barite (particles size 150-380 μm) had a good state of fluidization. Fluidization qualities of LiF powders were better with the addition of coarse particles in the binary mixed system of LiF powders and barite sands. LiF powders achieved incipient fluidization when the amount of added barite sands up. Good particulate fluidization of LiF powders can be achieved when the additive proportion of barite sands was 60%. LiF powders can achieve the best particulate fluidization when particle size of barite sands is 180-250 μm with the same additive proportion. Aggregating mechanism of LiF powders was analyzed on the basis of experimental research. Calculation results revealed that fluidized agglomeration sizes of LiF powders were much smaller after adding barite sands, which could be attribuite to the broken and cut effect of coarse particles for LiF powders. The average fluidized agglomeration size of single LiF powders was 1 646 μm. However, the average of fluidized agglomeration size of the binary mixed system with 40% LiF powders and 60% barite sands (particles diameter 180-250 μm) was 299 μm. Both the experiment and calculation results exhibited that adding barite particles is an effective method for improving the fluidized quality of LiF powders.
Keywords: inorganic chemistry; agglomerate model; fluidization; powders
 
Title: Stability analysis of rigid-liquid-flexible coupling dynamics of spacecraft systems by using the energy-Casimir method
Authors: YAN Yulong, YUE Baozeng, LIU Feng
PP: 718-730
Abstract: The coupling spacecraft stability analysis plays an important role in the study of dynamics and control of spacecraft. The stability of liquid filled spacecraft with flexible appendage was researched by using energy-Casimir method. Liquid sloshing dynamics was simplified by spring-mass model, and flexible appendage was modeled as a linear shearing beam. Rigid-liquid-flexible coupling dynamics of spacecraft was built. The energy function and the Casimir function were derived by analyzing the energy function of a rigid body, liquid sloshing and a flexible appendage. The nonlinear stability condition of coupled spacecraft system was derived by computing the first and second variation of Casimir function which we added to the energy function. The stable and unstable regions of the parameter space were given in the final section with numerical computation. Related results showed that the inertia matrix, the length of shearing beam, the spacecraft spinning rate, and the filled ratio of liquid fuel tank have strong influence on the stability of coupled spacecraft system.
Keywords: basic mechanics; nonlinear stability; energy-Casimir method; liquid sloshing
 
Title: Multiscale simulation of indenter size effect of nanoindentation in single crystal materials
Authors: YANG Zengjie, WANG Zhenqing
PP: 711-717
Abstract: In order to study the size effect in nano indentation, this paper adopts separate quasi-particle multiscale method to study the nano-indentation problem of single crystal material, such as copper, aluminum and silver. The simulation results show that for the different widths, the displacement-response curves of three materials show a distinct difference. For the greater width indenter, the load-displacement curve in elastic stage has a bigger curve slope, a larger load critical corresponding to plastic deformation, a larger critical displacement of indenter, and a later time appearing the dislocation nucleation. After the plastic deformation occurs, the load value will begin to decrease, and the dislocation nucleation appears in the material. The load-displacement curve for the single copper and aluminum only has a reduction process, while shows a multiple fluctuation for the single silver.
Keywords: solid mechanics; multiscale simulation; single-crystal copper; nanoindentation; size defect
 
Title: Influence of convection term coefficient of Navier-Stokes equations on turbulent properties
Authors: YANG Yuyao
PP: 702-710
Abstract: In order to study the universality of Kolmogorov constant and turbulent dissipation constant, basing on Navier-Stokes (N-S) equations with modified convection term coefficient, using the pseudo-spectral method, a direct numerical simulation (DNS) was carried out. How the modified convection term coefficient will change the Kolmogorov constant, turbulent dissipation constant as well as other proprieties of homogeneous isotropic incompressible flow such as spatial intermittency was investigated. A deterministic forcing scheme was applied on large scales to keep the statistical steady state of the turbulence. Simulation results show that convection term coefficient will change the Kolmogorov constant and turbulent dissipation constant but turbulence properties as spatial intermittency only depends on the separation degree between integral and Kolmogorov scales.
Keywords: fluid mechanics; turbulence theory; direct numerical simulation; incompressible homogenous isotropic turbulence; nonlinear intensity
 
Title: Research on the wave-maker boundary condition of the GN models in shallow water
Authors: ZHAO Binbin, DUAN Wenyang
PP: 695-701
Abstract: A new wave-maker boundary condition based on the stream function wave theory is presented in the GN wave theory. The least square method is used to calculate the wave function theory of convection velocity fitted according to the theory of GN velocity assumption, necessary velocity coefficient was obtained numerically using GN wave theory. In the case of strong nonlinear conditions (first order cnoidal wave theory cannot give accurate results), the proposed wave-maker boundary condition based on the results of the stream function wave theory is strongly advised. In addition, it is suggested to use the GN-3 theory instead of the GN-1 theory when simulating strong nonlinear shallow water wave.
Keywords: fluid mechanics; GN wave model; cnoidal waves; least square method; GN-3 model
 
Title: High pressure Raman study of p-terphenyl
Authors: LIU Chunyu, MA Zhiwei, ZHOU Mi
PP: 688-694
Abstract: High pressure Raman spectra of p-terphenyl have been measured up to 5 GPa. We analyze the Raman active change of different molecular point group symmetry using group theory, and obtain p-terphenyl molecular structure change from a twist C2 to planar D2h symmetry point group through the disappearing of Raman modes. A phase transition of p-terphenyl is obtained based on the frequency-pressure relationship at around 1.3 GPa, and a new method to identify the molecular planar structure is proposed based on phenyl ring stretching vibration of p-terphenyl, which can provide an evidence of pressure-induce structure change of conjugated polyphenyl.
Keywords: optics; p-terphenyl; phase transition; high pressure; Raman spectroscopy
 
Title: Eigenvalues and eigenstates of the evolution operator of quantum walks on cycles
Authors: LI Yingtian, XU Xinping
PP: 683-687
Abstract: We investigate the eigenvalues and eigenstates of the evolution operator of the discrete-time quantum random walk on the cycles. Using the Chebyshev polynomial method, we derive exact analytical expression of the eigenvalues and eigenstates of the evolution operator for the first time. It is found that the eigenvalues of the evolution operator are closely related to the Chebyshev polynomial of the first kind, the eigenstates of the evolution operator are closely related to the Bloch function in condensed matter physics. Our results provide important information to analyze the dynamical properties of discrete-time quantum random walk.
Keywords: theoretical physics; statistical physics and complex system; random walk; quantum random walk; complex network
 
Title: Illiquidity, investor sentiment and stock pricing: the empirical analysis based on panel data
Authors: FU Guorong, HUANG Wei
PP: 676-682
Abstract: In this paper, skewness, illiquidity cost and investor sentiment factors are built based on the trading data of Shanghai A-share from January 2007 to December 2014 and illiquid cost and turnover rate are taken as measure of liquidity. Considering the rigorous and impractical assumption of traditional capital asset pricing model (CAPM) theory, a panel data regression model incorporating above factors is established. The results show that illiquidity cost and investor sentiment have significant impact on the asset pricing process by empirical test, hence reveal the existence of illiquidity compensation as well as vast noise traders in Chinese stock market. Meanwhile, the results show that system risk factor and skewness factor have no explanatory power in asset returns and the traditional capital asset pricing model doesn’t comply in Chinese stock market.
Keywords: financial mathematics; panel data regression model; capital asset pricing model; illiquidity cost; investor sentiment; skewness
 
Title: A kind of parallel difference method with high precision for the payment of dividend option pricing model
Authors: ZHAO Weijuan, YANG Xiaozhong, WU Lifei
PP: 662-675
Abstract: This paper is given the alternating three points group explicit (AGE-3) difference method for the payment of dividend option pricing model. On the basis of the improved Saul’yev asymmetric difference scheme, three points group explicit (GE-3) difference scheme for the model is constructed increasing with an implicit point, then constructs the AGE-3 difference method for the model. Theoretical analysis and numerical experiment demonstrate that AGE-3 difference method of the model is unconditional stable and the calculation results more precise than solution of the alternating group explicit (AGE). Numerical experiment also shows that the computing speed of AGE-3 scheme is close to AGE scheme, about 1/2 times faster than the improved Saul’yev asymmetric difference scheme, which confirms the parallel computation method of AGE-3 difference scheme given by this paper is effective and practical.
Keywords: financial mathematics; payment of dividend option pricing model; alternating three points group explicit scheme; parallel computing; numerical experiment
 
Title: Stability and bifurcation analysis of the time-delay HTLV-I
Authors: YANG Jihua, ZHANG Erli, LIU Mei
PP: 650-661
Abstract: The local stability of the equilibrium is discussed by analyzing the characteristic equation of the linearized system of original system at the equilibrium. The regions of linear stability of equilibrium are given, it is found that Hopf bifurcation and Hopf-zero bifurcation exist when the delay passes through a sequence of critical values and the chaos occurs when delay increase further. Then, using the center manifold theorem and the Hassard normal form method, the explicit formulas for determining the direction and stability of the Hopf bifurcation are determined. Finally, numerical simulations are carried out for supporting the analytic results.
Keywords: applied mathematics; stability; Hopf bifurcation; Hopf-zero bifurcation; chaos
 
Title: Analysis of the circle of Willis chaotic system based on pharmaceuticals
Authors: SUN Menghan, XIAO Jian, DONG Hailiang, ZHANG Xiaoqing
PP: 640-649
Abstract: A new model of the circle of Willis chaotic system is constructed through the introduction of antihypertensive drugs’ inspirit function. Phase portraits indicate that the system contains the chaotic attractor. The chaotic complex dynamic characteristics of the new system are analyzed, including the existence of chaotic attractor, the Lyapunov exponents and the Poincaré section. The influence of each parameter of the new Willis chaotic system on the system is investigated based on the numerical simulation. Finally, the effective control of antihypertensive drugs for cerebral aneurysm is investigated by the analysis of the phase portraits and Poincaré section.
Keywords: operational research; cerebral aneurysm; dynamic analysis; Lyapunov exponents; antihypertensive drug
 
Title: Spectral radius of fractional integral operators and its applications
Authors: FENG Yuqiang, ZHU Xing, WANG Weimin
PP: 633-639
Abstract: In this paper, properties of fractional integral operators are discussed. Gelfand formula and Stirling formula are used to calculate the fractional integral spectral radius in two cases. Then, the obtained conclusions are applied to investigate the solvability of fractional differential equations and the proof of a new fractional Gronwall tye inequality.
Keywords: functional analysis; fractional integral operators; spectral radius; Gelfand formula; Stirling formula