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Chinese Journal of Chemistry 2002年第12期20卷 1584-1590,1463页

作者： taher Mohammad Ali Department of Chemistry Shahid Bahonar University of Kerman Kerman IRAN

Vanadium is quantitatively retained on 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP)-ammonium tetraphenylborate with microcrystalline naphthalene or by a column method in the pH range of 2.1–4.5 from a large volume of aqueous solutions of various samples. After filtration, the solid mass consisting of the vanadium complex and naphthalene was dissolved with 5 mL of dimethylformamide and the metal was determined by the third derivative spectrophotometry. Vanadium complex can alternatively be quantitatively adsorbed on ammonium tetraphenylborate-naphthalene adsorbent packed in a column and determined similarly. About 0.05 μg of vanadium can be concentrated in a column from 250 mL of aqueous sample, where its concentration is as low as 0.2 ng/mL. The interference of a large number of anions and cations has been studied and the optimized conditions developed were utilized for the determination of trace amount of vanadium in various samples.

关键词： trace vanadium determination derivative spectrophotometry 5-Br-PADAP-TPB-naphthalene

Using statistical models and GIS to delimit the groundwater recharge potential areas and to estimate the infiltration rate: A case study of Nadhour-Sisseb-El Alem Basin, Tunisia

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Journal of Arid Land 2021年第11期13卷 1122-1141页

作者： Ali SOUEI taher ZOUAGHI Georesources Laboratory Water Researches and Technologies Center(WRTC)of Borj CedriaSoliman 8020Tunisia Department of Geology FSTUniversity of Tunis El ManarTunis C P 2092Tunisia Department of Geo-Exploration Techniques Faculty of Earth SciencesKing Abdulaziz UniversityJeddah 21589Saudi Arabia

The water resources of the Nadhour-Sisseb-El Alem Basin in Tunisia exhibit semi-arid and arid climatic *** induces an excessive pumping of groundwater,which creates drops in water level ranging about 1-2 m/***,these unfavorable conditions require interventions to rationalize integrated management in decision *** aim of this study is to determine a water recharge index(WRI),delineate the potential groundwater recharge area and estimate the potential groundwater recharge rate based on the integration of statistical models resulted from remote sensing imagery,GIS digital data(e.g.,lithology,soil,runoff),measured artificial recharge data,fuzzy set theory and multi-criteria decision making(MCDM)using the analytical hierarchy process(AHP).Eight factors affecting potential groundwater recharge were determined,namely lithology,soil,slope,topography,land cover/use,runoff,drainage and *** WRI is between 1.2 and 3.1,which is classified into five classes as poor,weak,moderate,good and very good sites of potential groundwater recharge *** very good and good classes occupied respectively 27%and 44%of the study *** potential groundwater recharge rate was 43%of total *** to the results of the study,river beds are favorable sites for groundwater recharge.

关键词： potential recharge remote sensing statistical models MCDM Nadhour-Sisseb-El Alem Basin

Thermal Conductivity of Low-Density Polyethylene Foams Part Ⅱ: Deep Investigation using Response Surface Methodology

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Journal of Thermal Science 2020年第1期29卷 159-168页

作者： HASANZADEH Rezgar AZDAST taher DONIAVI Ali Department of Mechanical Engineering Urmia University

Here,we conducted a deep study on the thermal insulation performance of polymeric foams using response surface methodology(RSM).Cell size,foam density,and cell wall thickness were considered as variable *** of variance(ANOVA)tool was utilized to recognize the effective parameters on the different mechanisms of heat *** models were presented to forecast the different mechanisms of heat transfer and their validities were checked using ANOVA tool as well as compared to the thermal conductivity *** plots were used to study the interaction effect of significant *** optimization procedure was performed using *** density and cell wall thickness are effective parameters on the solid thermal conductivity whereas cell size and foam density were significant parameters on the thermal *** decreasing foam density,gaseous thermal conductivity and thermal radiation were increased and solid thermal conductivity was *** regression model predicted the overall thermal conductivity with an average error smaller than 3%.The results illuminated that the overall thermal conductivity in the optimum conditions was as small as 29 mW/mK.

关键词： thermal insulation polymer foams response surface methodology

On Network Designs with Coding Error Detection and Correction Application

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Computers, Materials & Continua 2021年第6期67卷 3401-3418页

作者： Mahmoud Higazy taher A.Nofal Department of Mathematics and Statistics College of ScienceTaif UniversityTaif21944Saudi Arabia Department of Physics and Engineering Mathematics Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

The detection of error and its correction is an important area of mathematics that is vastly constructed in all communication ***,combinatorial design theory has several applications like detecting or correcting errors in communication ***(graph)designs(GDs)are introduced as a generalization of the symmetric balanced incomplete block designs(BIBDs)that are utilized directly in the above mentioned *** networks(graphs)have been represented by vectors whose entries are the labels of the vertices related to the lengths of edges linked to ***,a general method is proposed and applied to construct new networks *** method of networks representation has simplified the method of constructing the network *** this paper,a novel representation of networks is introduced and used as a technique of constructing the group generated network designs of the complete bipartite networks and certain circulants.A technique of constructing the group generated network designs of the circulants is given with group generated graph designs(GDs)of certain *** addition,the GDs are transformed into an incidence matrices,the rows and the columns of these matrices can be both viewed as a binary nonlinear code.A novel coding error detection and correction application is proposed and examined.

关键词： Network decomposition network designs network edge covering circulant graphs

A hybrid evolutionary algorithm for distribution feeder reconfiguration

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Science China(Technological Sciences) 2010年第4期53卷 950-959页

作者： taher NIKNAM Ehsan AZAD FARSANI Electronic and Electrical Department Shiraz University of Technology

This paper presents a new method to reduce the distribution system loss by feeder *** new method combines self-adaptive particle swarm optimization(SAPSO) with shuffled frog-leaping algorithm(SFLA) in an attempt to find the global optimal solutions for the distribution feeder reconfiguration(DFR).In PSO algorithm,appropriate adjustment of the parameters is cumbersome and usually requires a lot of time and ***,a self-adaptive framework is proposed to improve the robustness of *** SAPSO the learning factors of PSO coevolve with the *** is combined with the SAPSO algorithm to improve its *** proposed algorithm is tested on two distribution test *** results of simulation show that the proposed algorithm is very powerful and guarantees to obtain the global optimization in minimum time.

关键词： self-adaptive particle swarm optimization(SAPSO) discrete particle swarm optimization(DPSO) binary particle swarm optimization(BPSO) shuffled frog-leaping algorithm(SFLA) evolutionary algorithms(EA) distribution feeder reconfiguration(DFR)

Low-temperature electrochemical synthesis and characterization of ultrafine Y(OH)_3 and Y_2O_3 nanoparticles

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Journal of Rare Earths 2012年第3期30卷 236-240页

作者： Mustafa AGHAZADEH taher YOUSEFI Mehdi GHAEMI Laser and Optic Research School NSTRI P.O. Box 11365-8486 Tehran Iran Material Research School NSTRI P.O. Box 14395-836 Tehran Iran Department of Chemistry Science Faculty Golestan University P.O. Box 49138-15739 Gorgan Iran

Ultrafine Y（OH）3 nanoparticles were successfully deposited from an additive-free 0.005 mol/L YCl3 low-temperature bath on the steel cathode at the current density of 0.5 mA/cm2 and bath temperature of 10 oC. Heat treatment of the prepared Y（OH）3 nanoparticles at 600 oC in air led to the formation of Y2O3 nanoparticles. Thermal behavior and phase transformation during the heat treatment of Y（OH）3 were investigated by differential scanning calorimetry （DSC） and thermogramimetric analysis （TGA）. The morphologies, crystal structures and compositions of the prepared materials were examined by means of scanning and transmission electron microscopy （SEM and TEM） as well as X-ray diffraction （XRD） and FT-IR spectroscopy. The results showed that the prepared Y（OH）3 nanoparticles was essentially amorphous and composed of well dispersed ultrafine particles with size of 4 nm. After heat treatment, the obtained oxide product was well crystallized cubic phase of Y2O3 nanoparticles with the grain size of around 5 nm. It was concluded that low-temperature cathodic electrodeposition offered a facile and feasible way for preparation of ultrafine Y（OH）3 and Y2O3 nanoparticles.

关键词： Y(OH)3 Y2O3 cathodic electrodeposition heat treatment nanoparticles rare earths

Intraspinal transplantation of motoneuron-like cell combined with delivery of polymer-based glial cell line-derived neurotrophic factor for repair of spinal cord contusion injury

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Neural Regeneration Research 2014年第10期9卷 1003-1013页

作者： Alireza Abdanipour Taki Tiraihi taher taheri Shefa Neuroscience Research Center at Khatam Al-Anbia Hospital

To evaluate the effects of glial cell line-derived neurotrophic factor transplantation combined with adipose-derived stem cells-transdifferentiated motoneuron delivery on spinal cord con-tusion injury, we developed rat models of spinal cord contusion injury, 7 days later, injected adipose-derived stem cells-transdifferentiated motoneurons into the epicenter, rostral and caudal regions of the impact site and simultaneously transplanted glial cell line-derived neuro-trophic factor-gelfoam complex into the myelin sheath. Motoneuron-like cell transplantation combined with glial cell line-derived neurotrophic factor delivery reduced cavity formations and increased cell density in the transplantation site. The combined therapy exhibited superior promoting effects on recovery of motor function to transplantation of glial cell line-derived neurotrophic factor, adipose-derived stem cells or motoneurons alone. These ifndings suggest that motoneuron-like cell transplantation combined with glial cell line-derived neurotrophic factor delivery holds a great promise for repair of spinal cord injury.

关键词： nerve regeneration spinal cord injury adipose-derived stem cells glial cell line-derived neurotrophic factor motoneurons cell transplantation neurotrophic factor spinal cord contusion injury neural regeneration

OSCILLATION CRITERIA FOR SECOND ORDER NONLINEAR DYNAMIC EQUATIONS WITH p-LAPLACIAN AND DAMPING

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Acta Mathematica Scientia 2013年第4期33卷 975-988页

作者： taher S.HASSAN Qingkai KONG Department of Mathematics Faculty of Science Mansoura University Department of Mathematics Northern Illinois University

This paper concerns the oscillation of solutions of the second order nonlinear dynamic equation with p-Laplacian and damping（r（t）φ（x^△（t））^△＋p（t）φα（x^△α（t）＋q（t）f（xδ（t））=0on a time scale T which is unbounded above. Sign changes are allowed for the coefficient functions r, p and q. Several examples are given to illustrate the main results.

关键词： oscillation dynamic equations time scales

An efficient hybrid evolutionary optimization algorithm based on PSO and SA for clustering

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第4期10卷 512-519页

作者： taher NIKNAM Babak AMIRI Javad OLAMAEI Ali AREFI Electronic and Electrical Engineering Department Shiraz University of TechnologyShirazIran Information Technology Department Islamic Azad University-Fars Science and Research BranchShiraz Iran Technical Engineering Department Islamic Azad University-South Tehran BranchTehran Iran Power Engineering Group Department of Electrical and Computer Engineering Tarbiat Modares UniversityTehran Iran

The K-means algorithm is one of the most popular techniques in clustering. Nevertheless, the performance of the Kmeans algorithm depends highly on initial cluster centers and converges to local minima. This paper proposes a hybrid evolutionary programming based clustering algorithm, called PSO-SA, by combining particle swarm optimization (PSO) and simulated annealing (SA). The basic idea is to search around the global solution by SA and to increase the information exchange among particles using a mutation operator to escape local optima. Three datasets, Iris, Wisconsin Breast Cancer, and Ripley's Glass, have been considered to show the effectiveness of the proposed clustering algorithm in providing optimal clusters. The simulation results show that the PSO-SA clustering algorithm not only has a better response but also converges more quickly than the K-means, PSO, and SA algorithms.

关键词： Simulated annealing (SA) Data clustering Hybrid evolutionary optimization algorithm K-means clustering Parti-cle swarm optimization (PSO)

Synthesis of Gd_2O_3 nanoparticles:using bulk Gd_2O_3 powders as precursor

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Rare Metals 2015年第8期34卷 540-545页

作者： taher Yousefi Meisam Torab-Mostaedi Mostafa Ghasemi Amir Ghadirifar Nuclear Fuel Cycle Research School Nuclear Science andTechnology Research Institute

Gd2O3nanoparticles were synthesized from the commercial bulk Gd2O3 powders via a simple electrochemical method. The synthesized powders were characterized by means of X-ray powder diffraction(XRD),scanning electron microscopy(SEM), transmission electron microscopy(TEM) and Fourier transform infrared(FTIR) spectroscopy. The effects of solution p H on the morphological features of the sample were studied. The strategy developed in this study offers significant advantages for the synthesis of Gd2O3 nanoparticles from the bulk Gd2O3 powders compared with the conventional routes. From SEM observations, the size of the Gd2O3 nanoparticles is estimated to be significantly smaller than70 nm.

关键词： Gd2O3 Nanoparticles Electro-deposition Nanostructu