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Simultaneous extraction and preconcentration of copper,silver and palladium with modified alumina and their determination by electrothermal atomic absorption spectrometry

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Chinese Chemical Letters 2014年第4期25卷 649-654页

作者： Mohammad Ali taher Zahra Daliri Hamid Fazelirad Department of Chemistry Shahid Bahonar University of Kerman Department of Polymer Science and Research BranchIslamic Azad University Young Researchers Society Shahid Bahonar University of Kerman

In the present work, an easy solid phase extraction method using alumina modified with polyethylenimine as a new adsorbent was applied to the simultaneous extraction of copper, silver, and palladium ions prior to their determination with electrothermal atomic absorption spectrometry. The analytical procedure involved the complex formation of these cations with polyethylenimine as a chelating agent in buffer media of pH 7.0. Under the optimum conditions, a preconcentration factor of 200, 150, and 200, precision of ~5.4%, ＋4.7%, and ＋5.2% and linear calibration ranges of 15.0-140, 4.0-93, and 7.5-125 ng/L （in original solution） for Cu, Ag, and Pd were obtained, respectively. Also detection limits of 3.9,1.1, and 2.0 ng/L were obtained for Cu, Ag, and Pd, respectively. The proposed method was applied to the determination of copper, silver, and palladium in some real samples with satisfactory results.

关键词： Polyethylenimine Solid phase extraction Copper Silver Palladium Electrothermal atomic absorptionspectrometry

Influence of mulching and tree shelters on 4-year survival and growth of zeen oak (Quercus canariensis) seedlings

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Journal of Forestry Research 2019年第1期30卷 129-141页

作者： taher Mechergui Marta Pardos Douglass F.Jacobs Facultédes Sciences de Bizerte Laboratoire des Ressources Sylvo-Pastorales (Institut Sylvo-Pastoral de Tabarka) Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria (INIA) Centro de Investigacion Forestal Department of Forestry and Natural Resources Hardwood Tree Improvement and Regeneration Center Purdue University

We assessed the effect of mulching and tree shelters on the establishment and early growth of zeen oak(Quercus canariensis Willd.) during the first 4 years after planting in Northwestern Tunisia. Five mulch types(Italian Stone Pine(Pinus pinea L.), Lentisk(Pistacia lentiscus L.),and a combination of Italian Stone Pine and Lentisk(organic mulches), gravel(inorganic mulch) and control), and three tree shelter types(non-vented and vented tree shelters, and control) were tested. An increase in the number of internodes occurred under the gravel mulch, while a reduction in survival was found for the lentisk mulch. Tree shelters had no effect on survival, but increased mean height growth and reduced mean diameter growth during the 4 years(excepting a non-significant effect for vented tree shelter at year four). Comparison of the annual shoots and growth units(GU) between sheltered and unsheltered plants according to year of formation revealed two growth phases. In first phase, shoots were totally or partially inside the shelters; mean length of annual shoots and GU were greater for sheltered plants. The second phase was characterized by shoots emerging from shelters; mean length of annual shoots and GU were similar for all plants, with or without tree shelters. Results suggest that the use of tree shelters, particularly vented shelters, could contribute to the improvement of the artificial regeneration of zeen *** use of mulching alone or in combination with tree shelters did not improve zeen oak performance in the field.

关键词： Zeen oak Mulching Tree shelters Plantation Survival rate Growth

Duffing Oscillator’s Vibration Control under Resonance with a Negative Velocity Feedback Control and Time Delay

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Sound & Vibration 2021年第3期55卷 191-201页

作者： Y.A.Amer taher A.Bahnasy Department of Mathematics Faculty of ScienceZagazig UniversityZagazigEgypt Department of Engineering Physics and Mathematics Faculty of EngineeringTanta UniversityTantaEgypt

An externally excited Duffing oscillator under feedback control is discussed and analyzed under the worst resonance *** time scales method is applied for this system to find analytic solution with the existence and nonexistence of the time delay on control *** appropriate stability analysis is also performed and appropriate choices for the feedback gains and the time delay are found in order to reduce the amplitude *** response curves are involved to show and compare controller *** addition,analytic solutions are compared with numerical approximation solutions using Rung-Kutta method of fourth order.

关键词： Non-linear dynamical system multiple time scales method active feedback controller time delay

Vitamin B12: An efficient type catalyst for the one-pot synthesis of 3,4,5-trisubstituted furan-2(5H)-ones and N-aryl-3-aminodihydropyrrol-2-one-4-carboxylates

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Chinese Chemical Letters 2016年第1期27卷 66-70页

作者： Mehrnoosh Kangani Malek-taher Maghsoodlou Nourallah Hazeri Department of Chemistry Faculty of Sciences University of Sistan and Baluchestan

Vitamin B12 was applied as catalyst for the one-pot three-component synthesis of 3,4,5-trisubstituted furan-2（5H）-ones from the condensation between aldehydes, amines and dialkylacetylendicarboxylates at ambient temperature in Et OH. In addition, N-aryl-3-aminodihydropyrrol-2-one-4-carboxylates were synthesised using mentioned catalyst at ambient temperature in Et OH from condensation between formaldehyde, amines, and dialkylacetylenedicarboxylates. This methodology has number of advantages such as： use of green and nonhazardous catalyst, clean work up, short reaction times,high yields and no need to column chromatography.

关键词： Vitamin B12 3,4,5-Trisubstituted furan-2(5H)-ones N-aryl-3-aminodihydropyrrol-2-one-4- carboxylates

FORCED OSCILLATION OF SECOND ORDER DIFFERENTIAL EQUATIONS WITH MIXED NONLINEARITIES

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Acta Mathematica Scientia 2011年第2期31卷 613-626页

作者： taher S. Hassan Lynn Erbe Allan Peterson Department of Mathematics Faculty of Science Mansoura University Department of Mathematics University of Nebraska-Lincoln

This article is concerned with the oscillation of the forced second order differ- ential equation with mixed nonlinearities（a（t）（x＇（t））γ）＇＋po（t）xγ（go（t））＋n∑t=1pi（t）｜x（gi（t））｜αi sgn x（gi（t））=e（t）,where γ is a quotient of odd positive integers αi〉0,i=1,2 ……n,a,e,and pi ∈ C（[0,∞）R）,a（t）〉0,gi：R→R are positive continuous functions on R with lim gi （t）=∞,i=0,1,……,n. Our results generalize and improve the results in a recent article by Sun and Wong[29].

关键词： Oscillation functional differentail equations second order

Swarm-Based Extreme Learning Machine Models for Global Optimization

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Computers, Materials & Continua 2022年第3期70卷 6339-6363页

作者： Mustafa Abdul Salam Ahmad taher Azar Rana Hussien Artificial Intelligence Department Faculty of Computers and Artificial IntelligenceBenha UniversityBenha13518Egypt Scientific Computing Department Faculty of Computers and Artificial IntelligenceBenha UniversityBenha13518Egypt

Extreme Learning Machine(ELM)is popular in batch learning,sequential learning,and progressive learning,due to its speed,easy integration,and generalization ***,Traditional ELM cannot train massive data rapidly and efficiently due to its memory residence,high time and space *** ELM,the hidden layer typically necessitates a huge number of ***,there is no certainty that the arrangement of weights and biases within the hidden layer is *** solve this problem,the traditional ELM has been hybridized with swarm intelligence optimization *** paper displays five proposed hybrid Algorithms“Salp Swarm Algorithm(SSA-ELM),Grasshopper Algorithm(GOA-ELM),Grey Wolf Algorithm(GWO-ELM),Whale optimizationAlgorithm(WOA-ELM)andMoth Flame Optimization(MFO-ELM)”.These five optimizers are hybridized with standard ELM methodology for resolving the tumor type classification using gene expression *** proposed models applied to the predication of electricity loading data,that describes the energy use of a single residence over a fouryear *** the hidden layer,Swarm algorithms are used to pick a smaller number of nodes to speed up the execution of *** best weights and preferences were calculated by these algorithms for the hidden *** results demonstrated that the proposed MFO-ELM achieved 98.13%accuracy and this is the highest model in accuracy in tumor type classification gene expression *** in predication,the proposed GOA-ELM achieved 0.397which is least RMSE compared to the other models.

关键词： Extreme learning machine salp swarm optimization algorithm grasshopper optimization algorithm grey wolf optimization algorithm moth flame optimization algorithm bio-inspired optimization classification model and whale optimization algorithm

Facile synthesis, morphology and structure of Dy_2O_3 nanoparticles through electrochemical precipitation

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Rare Metals 2016年第8期35卷 637-642页

作者： taher Yousefi Meisam Torab-Mostaedi Abolfazl Aghaei Hossein Ghasemi-Mobtaker Nuclear Fuel Cycle Research School Nuclear Science and Technology Research Institute

The aim of this research was to introduce a new, facile and simple method for synthesis of Dy203 nanostructures at room temperature. For the first time, galvanostatic electrodeposition was used to synthesize Dy203 particles, and the influence of the current density on the structure and morphology of the product was studied. The samples were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM） and Brunauer-Emmett-Teller （BET）. The results show that the current density has little effect on the chemical composi- tion but great effect on the structure and morphology of the samples. The average size of the particles decreases as the applied current density increases. The grain size of as- prepared samples decreases from 500 to 70 nm when the current density increases from 0.5 to 6.0 ***-a. To obtain oxide product, the as-prepared samples were heat- treated at 1,000 ℃. The results show that the heat-treated samples have smaller particles. The XRD results show that the similar patterns are observed in the samples synthesized at different current densities, and the only difference from the JCPDS card is the ratio of peak intensities. With the increase in the current density, a decrease in the current efficiency is observed.

关键词： Dy203 Nanoparticle Electrodeposition Nanostructures Rare earth

Wavelet based approximations in the optimal control of parabolic problems

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控制理论与应用（英文版） 2013年第1期11卷 103-107页

作者： taher ABUALRUB Ibrahim SADEK Farah EL NACHAR Department of Mathematics and Statistics American University of Sharjah

We consider optimal control of a bilinear parabolic equation. The determination of such control requires to minimize a given energy performance measure. The performance measure of the system is taken as a combination of its modified total energy and the penalty term describing the approach used in the control process. Using an appropriate transformation modal expansion, the optimal control of a distributed parameter system （DPS） is simplified into the optimal control of a bilinear time-varying lumped parameter system （LPS）. A computational efficient formulation to evaluate the optimal trajectory and control of the system is determined. It is based on the parametrization of the state and control variables by using finite wavelets. Numerical examples are provided to demonstrate the applicability and the efficiency of the proposed method and the results are quite satisfactory.

关键词： Bilinear system Parabolic equation Optimal control CAS wavelets

Autoantibody profiles in autoimmune hepatitis and chronic hepatitis C identifies similarities in patients with severe disease

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World Journal of Gastroenterology 2017年第8期23卷 1345-1352页

作者： Kawa Amin Aram H Rasool Ali Hattem Taha AM Al-Karboly taher E taher Jonas Bystrom Department of Medical Science Respiratory Medicine and AllergologyClinical Chemistry and Asthma Research CentreUppsala University and University Hospital Department of Microbiology/Immunology School of MedicineUniversity of Sulaimani Laboratory Department General Hospital of Derbandixan Department of Community Health Sulaimani Polytechnic University Department of Medicine School of MedicineFaculty of Medical SciencesUniversity of Sulaimani Experimental Medicine and Rheumatology William Harvey Research InstituteBarts and the LondonQueen MaryUniversity of London

To determine how the auto-antibodies (Abs) profiles overlap in chronic hepatitis C infection (CHC) and autoimmune hepatitis (AIH) and correlate to liver *** of antinuclear Ab, smooth muscle antibody (SMA) and liver/kidney microsomal-1 (LKM-1) Ab and markers of liver damage were determined in the sera of 50 patients with CHC infection, 20 AIH patients and 20 healthy controls using enzyme linked immunosorbent assay and other immune *** found that AIH patients had more severe liver disease as determined by elevation of total IgG, alkaline phosphatase, total serum bilirubin and serum transaminases and significantly higher prevalence of the three non-organ-specific autoantibodies (auto-Abs) than CHC patients. Antinuclear Ab, SMA and LKM-1 Ab were also present in 36% of CHC patients and related to disease severity. CHC cases positive for auto-Abs were directly comparable to AIH in respect of most markers of liver damage and total IgG. These cases had longer disease duration compared with auto-Ab negative cases, but there was no difference in gender, age or viral load. KLM-1+ Ab CHC cases showed best overlap with ***-Ab levels in CHC may be important markers of disease severity and positive cases have a disease similar to AIH. Auto-Abs might have a pathogenic role as indicated by elevated markers of liver damage. Future studies will unravel any novel associations between these two diseases, whether genetic or other.

关键词： Autoantibody Inflammatory diseases Immune system Hepatitis C virus Smooth muscle antibody Liver/kidney microsomal-1 autoantibody Anti-nuclear antibody