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Exact solutions for nonlinear partial fractional differential equations

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Chinese Physics B 2012年第11期21卷 32-38页

作者： Khaled A.Gepreel Saleh Omran Mathematics Department Faculty of ScienceZagazig University Mathematics Department Faculty of ScienceTaif University Mathematics Department Faculty of scienceSouth Valley University

′In this article, we use the fractional complex transformation to convert nonlinear partial fractional differential equations to nonlinear ordinary differential equations. We use the improved （G′/G）-expansion function method to calculate the exact solutions to the time- and space-fractional derivative foam drainage equation and the time- and space-fractional derivative nonlinear KdV equation. This method is efficient and powerful for solving wide classes of nonlinear evolution fractional order equations.

关键词： fractional calculus complex transformation modified Riemann-Liouville derivative im- proved (G′/G)-expansion function method

Sonochemical synthesis and characterization of uniform lanthanide orthophosphate(LnPO_4, Ln=La and Ce) nanorods

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Rare Metals 2015年第5期34卷 301-307页

作者： Anukorn Phuruangrat Titipun Thongtem Somchai Thongtem Department of Materials science and Technology Faculty of Science Prince of Songkla University Department of Chemistry Faculty of Science Chiang Mai University Department of Physics and Materials science Faculty of Science Chiang Mai University

Uniform lanthanide orthophosphate （LnPO4, Ln = La and Ce） nanorods were successfully synthesized by a simple ultrasonic irradiation method using lanthanide nitrate salt （Ln（NO3）3-6H2O, Ln = La and Ce） and sodium phosphate （Na3PO4） in aqueous solutions with the pH of 1-3. The products were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, high-resolution transmission electron microscopy （HRTEM）, Fourier transform infrared spectrometer （FT-IR）, and UV-visible （UV-Vis） spectroscopy. In this research, the products are nanorods of monoclinic LaPO4 and hexagonal CePOa structures and the vibration modes of PO4^3-, including the strong peaks at 227 nm for LaPO4, and at 225 and 278 nm for CePO4.

关键词： Ultrasonic Lanthanide orthophosphate Nanorods irradiation

Adsorption-oxidation of hydrogen sulfide on Fe/walnut-shell activated carbon surface modified by NH_3-plasma

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Journal of Environmental sciences 2018年第2期30卷 216-226页

作者： Ping Ning Sijian Liu Chi Wang Kai Li Xin Sun Lihong Tang Gui Liu faculty of Environmental science and Engineering Kunming University of Science and Technology faculty of Chemical Engineering Kunming University of Science and Technology

Walnut-shell activated carbon（WSAC） supported ferric oxide was modified by non-thermal plasma（NTP）, and the removal efficiency for hydrogen sulfide over Fe/WSAC modified by dielectric barrier discharge（DBD） was significantly promoted. The sample modified for10 min and 6.8 k V output（30 V input voltage） maintained 100% H2 S conversion over a long reaction time of 390 min. The surface properties of adsorbents modified by NTP under different conditions were evaluated by the methods of X-ray photoelectron spectroscopy（XPS）, Brunauer–Emmett–Teller（BET） analysis and in-situ Fourier transform infrared spectroscopy（FTIR）, to help understand the effect of the NTP treatment. NTP treatment enhanced the adsorption capacity of Fe/WSAC, which could due to the formation of micro-pores with sizes of0.4, 0.5 and 0.75 nm. XPS revealed that chemisorbed oxygen changed into lattice oxygen after NTP treatment, and lattice oxygen is beneficial for H2 S oxidation. From the in-situ FTIR result,transformation of the reaction path on Fe/WSAC was observed after NTP modification. The research results indicate that NTP is an effective method to improve the surface properties of the Fe/WSAC catalyst for H2 S adsorption-oxidation.

关键词： Dielectric barrier discharge Non-thermal plasma Surface modification Hydrogen sulfide Fe/walnut-shell activated carbon(Fe/WSAC)

Thermomechanical Analysis of (Cu_(0.5)Tl_(0.5))-1223 Substituted by Pr and La

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Journal of Materials science & Technology 2012年第2期28卷 169-176页

作者： A.I.Abou Aly R.Awad I.H.Ibrahim M.Kamal M.Anas Physics Department Faculty of ScienceAlexandria University Physics Department Faculty of ScienceMansoura University

The thermomechanical analysis （TMA） of Cu0.5T10.5Ba2Ca2-xRxCu30110-δ, where R=Pr and La, with 0.0〈x〈0.15, was carried out in temperature range from 450 to 1145 K. The samples were prepared by singlestep solid state reaction technique. The prepared samples were characterized by X-ray diffraction （XRD） and scanning electron microscopy （SEM）. The superconductivity of the prepared samples was investigated by electrical resistivity measurement. The results showed that low substitution content enhanced the （Cu0.5Tlo.5）- 1223 phase formation, while the higher substitution content degraded this phase. The higher superconducting transition temperatures Tc were found to be 114 K and 109 K at x= 0.025 for Pr- and La-substitutions, respectively. The average linear thermal expansion coefficient increased as x increased, while the shrinkage temperature decreased as x increased. Those results were emphasized by porosity and Vickers microhardness calculations. Debye temperature 0D was calculated from the linear thermal expansion coefficient data and correlated to Tc to estimate the electron-phonon coupling λep.

关键词： (Cu0.5Tl0.5)-1223 Thermomechanical analysis Thermal expansion coefficient Debye temperature

Group solution for an unsteady non-Newtonian Hiemenz flow with variable fluid properties and suction/injection

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Chinese Physics B 2014年第9期23卷 43-53页

作者： H.M.El-Hawary Mostafa A.A.Mahmoud Reda G.Abdel-Rahman Abeer S.Elfeshawey Department of Mathematics Faculty of ScienceAssuit University Department of Mathematics Faculty of ScienceBenha University

The theoretic transformation group approach is applied to address the problem of unsteady boundary layer flow of a non-Newtonian fluid near a stagnation point with variable viscosity and thermal conductivity. The application of a two- parameter group method reduces the number of independent variables by two, and consequently the governing partial differential equations with the boundary conditions transformed into a system of ordinary differential equations with the appropriate corresponding conditions. Two systems of ordinary differential equations have been solved numerically using a fourth-order Runge-Kutta algorithm with a shooting technique. The effects of various parameters governing the problem are investigated.

关键词： non-Newtonian fluid stagnation point two-parameter group method variable viscosity

Developed mathematical technique for fractional stochastic point kinetics model in nuclear reactor dynamics

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Nuclear science and Techniques 2018年第9期29卷 197-213页

作者： Ahmed E.Aboanber Abdallah A.Nahla Adel M.Edress Department of Mathematics Faculty of Science Taibah University Department of Mathematics Faculty of Science Tanta University

Fractional stochastic kinetics equations have proven to be valuable tools for the point reactor kinetics model, where the nuclear reactions are not fully described by deterministic relations. A fractional stochastic model for the point kinetics system with multi-group of precursors,including the effect of temperature feedback, has been developed and analyzed. A major mathematical and inflexible scheme to the point kinetics model is obtained by merging the fractional and stochastic technique. A novel split-step method including mathematical tools of the Laplace transforms, Mittage–Leffler function, eigenvalues of the coefficient matrix, and its corresponding eigenvectors have been used for the fractional stochastic matrix differential equation. The validity of the proposed technique has been demonstrated via calculations of the mean and standard deviation of neutrons and precursor populations for various reactivities: step, ramp, sinusoidal, and temperature reactivity feedback. The results of the proposed method agree well with the conventional one of the deterministic point kinetics equations.

关键词： Ito stochastic point kinetics equations Temperature feedback effects Wiener process Fractional calculus Mittage–Leffler function

A promising approach for quantifying focal stroke modeling and assessing stroke progression:optical resolution photoacoustic microscopy photothrombosis

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Neural Regeneration Research 2025年第7期20卷 2029-2037页

作者： Xiao Liang Xingping Quan Xiaorui Geng Yujing Huang Yonghua Zhao Lei Xi Zhen Yuan Ping Wang Bin Liu faculty of Health sciences University of MacaoMacao Special Administrative RegionChina Center for Cognitive and Brain sciences University of MacaoMacao Special Administrative RegionChina Department of Biomedical Engineering Southern University of Science and TechnologyShenzhenGuangdong ProvinceChina State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipaMacao Special Administrative RegionChina Department of Emergency Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral ***,these methods often require complex systems and the effect of age on cerebral embolism has not been adequately studied,although ischemic stroke is strongly *** this study,we propose an optical-resolution photoacoustic microscopy-based visualized photothrombosis methodology to create and monitor ischemic stroke in mice simultaneously using a 532 nm pulsed *** observed the molding process in mice of different ages and presented age-dependent vascular embolism ***,we integrated optical coherence tomography angiography to investigate age-associated trends in cerebrovascular variability following a *** imaging data and quantitative analyses underscore the differential cerebrovascular responses to stroke in mice of different ages,thereby highlighting the technique's potential for evaluating cerebrovascular health and unraveling age-related mechanisms involved in ischemic strokes.

关键词： age-dependent cerebral cortex ischemic stroke mouse model optical coherence tomography angiography photoacoustic microscopy photothrombosis vascular imaging

Locally Enhanced Flow and Electric Fields Through a Tip Effect for Efficient Flow‑Electrode Capacitive Deionization

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Nano-Micro Letters 2025年第2期17卷 1-17页

作者： Ziquan Wang Xiangfeng Chen Yuan Zhang Jie Ma Zhiqun Lin Amor Abdelkader Maria‑Magdalena Titirici Libo Deng College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060People’s Republic of China Research Center for Environmental Functional Materials College of Environmental Science and EngineeringTongji University1239 Siping RoadShanghai 200092People’s Republic of China Department of Chemical and Biomolecular Engineering National University of SingaporeSingapore 117585Singapore Department of Engineering Faculty of Science and TechnologyBournemouth UniversityTalbot CampusFern BarrowPooleEngland BH125BBUK Institut de Chimie de Nice UniversitéCôte d’AzurUMR CNRS 727228 Av.Valrose06108 NiceFrance Department of Chemical Engineering Imperial College LondonSouth Kensington CampusExhibition RdLondon SW72AZUK

Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of ***,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current ***,a new tip-array current collector(designated as T-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport *** effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal *** the voltage increased from 1.0 to 1.5 and 2.0 V,the T-CC-based FCDI system(T-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current ***,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for T-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current ***,a salt removal efficiency of 99.89%was achieved with T-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability.

关键词： Flow-electrode Capacitive deionization Current collector Tip effect Desalination

Noise composed of multiplication of two dichotomous noises

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Chinese Physics B 2008年第6期17卷 1990-1997页

作者：李静辉 faculty of science Ningbo University

In this paper, we introduce a noise which is composed of multiplication of two dichotomous noises, and derive the probability density and the statistical properties of this noise. The obtained results can help study the resonant activation phenomenon, the phenomenon of stochastic resonance, the transport of particles, and the nonequilibrium （phase） transition for the systems driven by this noise.

关键词： Dichotomous noise probability density statistical properties