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Generation of sodium hypochlorite (NaOCl) from sodium chloride solution using C/PbO_2 and Pb/PbO_2 electrodes

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International Journal of Minerals,Metallurgy and Materials 2012年第6期19卷 561-566页

作者： nasser Abu Ghalwa Hassan Tamos Mohamed ElAskalni Abed Rhman El Agha Chemistry Department Al-Azhar University of GazaP.O.Box 1277Palestine

Two modified electrodes （Pb/PbO2 and C/PbO2） were prepared by electrodepositing a lead oxide layer on lead and carbon sub- strates. These modified electrodes were used as anodes for the generation of sodium hypochlorite （NaOC1） from sodium chloride solution. Different operating conditions and factors affecting the treatment process of NaOC1 generation, including current density, pH values, con- ductive electrolytes, and electrolysis time, were studied and optimized. By comparison the C/PbO2 electrode shows a higher efficiency than the Pb/PbO2 electrode for the generation of NaOC1.

关键词： sodium hypochlorite sodium chloride lead oxide electrodeposition electrodes

Characterizing Spatial Variability of Soil Textural Fractions and Fractal Parameters Derived from Particle Size Distributions

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Pedosphere 2019年第2期29卷 224-234页

作者： Meysam MOHAMMADI Mahmoud SHABANPOUR Mohammad Hossein MOHAMMADI nasser DAVATGAR Department of Soil Science Faculty of Agriculture University of Guilan Department of Soil Science Faculty of Agricultural Engineering and Technology University of Tehran Department of Soil Science Research Institute of Soil and Water

Soil particle size distribution(PSD) is a fundamental physical property affecting other soil properties. Characterizing spatial variability of soil texture is very important in environmental research. The objectives of this work were: 1) to partition PSD of 75 soil samples, collected from a flat field in the University of Guilan, Iran, into two scaling domains using a piecewise fractal model to evaluate the relationships between fractal dimensions of scaling domains and soil clay, silt, and sand fractions and 2) to assess the potential of fractal parameters as an index used in a geostatistical approach reflecting the spatial variability of soil texture. Features of PSD of soil samples were studied using fractal geometry, and geostatistical techniques were used to characterize the spatial variability of fractal and soil textural parameters. There were two scaling domains for the PSD of soil samples. The fractal dimensions of these two scaling domains(D_1 and D_2) were then used to characterize different ranges of soil particle sizes and their relationships to the soil textural parameters. There was a positive correlation between D_1 and clay content(R^2= 0.924), a negative correlation between D_1 and silt content(R^2= 0.801), and a negative correlation between D_2 and sand content(R^2= 0.913). The geometric mean diameter of soil particles had a negative correlation with D_1(R^2= 0.569) and D_2(R^2= 0.682). Semivariograms of fractal dimensions and soil textural parameters were calculated and the maps of spatial variation of D_1 and D_2 and soil PSD parameters were provided using ordinary kriging. The results showed that there were also spatial correlations between D_1 and D_2 and particle size *** to the semivariogram models and validation parameters, the fractal parameters had powerful spatial structure and could better describe the spatial variability of soil texture.

关键词： fractal dimension geometric mean diameter geostatistical approach physical property semivariogram model statistical correlation

Effect of the degree of template removal from mesoporous silicate materials on their adsorption of heavy oil from aqueous solution

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Frontiers of Chemical Science and Engineering 2014年第4期8卷 488-497页

作者： Farouq TWAIQ M.S. nasser Sagheer A. ONAIZI Faculty of Engineering Computing and Science Swinbume University of Technology Kuching 93350 Malaysia Gas Processing Center College of Engineering Qatar University Doha P. O. Box 2713 Qatar School of Chemical Engineering and Advanced Materials Newcastle University Singapore 599489 Singapore School of Chemical Engineering and Advanced Materials Newcastle University Newcastle upon Tyne NE1 7RU UK

The key aim of this study is to evaluate the adsorption of heavy oil from aqueous solutions with different oil contents over mesoporous silicate materials having different surfactant template contents. The meso- porous silicate materials have been synthesized from tetraethylorthosilicate as a silica precursor and cetyltri- methylammonium bromide as a template using the sol-gel technique. Four samples were prepared by （1） totally removing the template using the calcination process, （2） partially removing the template via ethanol extraction, （3） partially removing the template via water extraction, and （4） keeping the template as synthesized, respectively. These four samples have been characterized using X-ray diffraction, nitrogen adsorption, thermal gravimetric ana- lysis and Fourier transformed infrared. The effect of the degree of template removal of these mesoporous materials for the oil removal has been investigated. The oil removal is inversely proportional to the surfactant content in the mesoporous material, being highest for the calcined sample but lowest for the as-synthesized sample. The kinetic of oil adsorption over the calcined material has been also studied and the data obtained fit well a second-order model.

关键词： adsorption heavy oil mesoporous silicatematerial kinetics template removal

Comparative studies on numerical sensitivity of different scenarios of enhanced oil recovery by water-alternating-gas(CO_(2))injection

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Petroleum Research 2023年第4期8卷 505-513页

作者： Saddam Mohammed Mohammed nasser Achinta Bera Vivek Ramalingam School of Energy Technology Pandit Deendayal Energy UniversityGandhinagarGujarat382007India

Enhanced oil recovery by CO_(2) injection technology(CO_(2)-EOR)plays a crucial role in enhancing oil production and the permanent sequestration of anthropogenic CO_(2) in depleted oil ***,the availability of CO_(2) in oil field locations and its mobility in contrast with reservoir fluids are prime challenges in CO_(2)-*** cost of CO_(2) and its availability at the oil fields has prompted investigations on efficient injection of CO_(2) at the fields to achieve the best sweep efficiency *** strategies such as water-alternating-gas(WAG),simultaneous vertical and horizontal WAG,simultaneous water injection into the aquifer and vertical WAG,water and gas injection simultaneously but separately(SS-WAG),and water and gas injection simultaneously but not separately(SNS-WAG)play a significant role,as well as the purity of CO_(2).In this work,the significance of the above criteria was investigated indi-vidually and in *** coupled sequence of injection rate,soaking time,WAG ratio,and purity of injected CO_(2) for enhancement of oil production were delineated.A realistic reservoir simulation model conceptualizing the CO_(2)-EOR system with five spot injection patterns was developed by the company *** history-matched model that was developed was used to investigate the sensitivity of the coupled effects to the criteria listed above on oil *** investigations quantitatively emphasized that purity and soaking time of CO_(2) have an inverse effect in the oil production rate and that SNS-WAG resulted in a better oil production rate than SS-WAG.

关键词： Water-alternating-gas Enhanced oil recovery Sensitivityanalysis Modelingand simulation Simultaneouslybut not separately water-alternating-gas(SS-WAG) Simultaneously pressure maintenance and WAG

NON-EXISTENCE FOR FRACTIONALLY DAMPED FRACTIONAL DIFFERENTIAL PROBLEMS

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Acta Mathematica Scientia 2017年第1期37卷 119-130页

作者： Mohnmmed D,KASSIM Khaled M.FURATI nasser-eddine TATAR Department of Mathematics and Statistics King Fahd University of Petroleum and MineralsDhahran31261Saudi Arabia

In this paper, we are concerned with a fractional differential inequality containing a lower order fractional derivative and a polynomial source term in the right hand side. A non-existence of non-trivial global solutions result is proved in an appropriate space by means of the test-function method. The range of blow up is found to depend only on the lower order derivative. This is in line with the well-known fact for an internally weakly damped wave equation that solutions will converge to solutions of the parabolic part.

关键词： nonexistence global solution fractional differential equation Riemann-Liouvillefractional integral and fractional derivative

Simultaneous knowledge-based identification and optimization of PHEV fuel economy using hyper-level Pareto-based chaotic Lamarckian immune algorithm, MSBA and fuzzy programming

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International Journal of Intelligent Computing and Cybernetics 2015年第1期8卷 2-27页

作者： Ahmad Mozaffari nasser L.Azad Alireza Fathi Systems Design Engineering Department University of WaterlooWaterlooCanada Department of Mechanical Engineering Babol University of TechnologyBabolIran

Purpose–The purpose of this paper is to probe the potentials of computational intelligence(CI)and bio-inspired computational tools for designing a hybrid framework which can simultaneously design an identifier to capture the underlying knowledge regarding a given plug-in hybrid electric vehicle’s(PHEVs)fuel cost and optimize its fuel consumption ***,the current investigation aims at elaborating the effectiveness of Pareto-based multiobjective programming for coping with the difficulties associated with such a tedious automotive engineering ***/methodology/approach–The hybrid intelligent tool is implemented in two different *** hyper-level algorithm is a Pareto-based memetic algorithm,known as the chaos-enhanced Lamarckian immune algorithm(CLIA),with three different objective *** a hyper-level supervisor,CLIA tries to design a fast and accurate identifier which,at the same time,can handle the effects of uncertainty as well as use this identifier to find the optimum design parameters of PHEV for improving the fuel ***–Based on the conducted numerical simulations,a set of interesting points are ***,it is observed that CI techniques provide us with a comprehensive tool capable of simultaneous identification/optimization of the PHEV operating *** is concluded that considering fuzzy polynomial programming enables us to not only design a proper identifier but also helps us capturing the undesired effects of uncertainty and measurement noises associated with the collected ***/value–To the best knowledge of the authors,this is the first attempt at implementing a comprehensive hybrid intelligent tool which can use a set of experimental data representing the behavior of PHEVs as the input and yields the optimized values of PHEV design parameters as the output.

关键词： Artificial immune system Fuzzy logic Knowledge acquisition Function approximation System identification Evolutionary computation

Evaluation of urea breath test as a diagnostic tool for Helicobacter pylori infection in adult dyspeptic patients

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World Journal of Gastroenterology 2024年第17期30卷 2302-2307页

作者： Zeinab Nabil Ahmed Said Asmaa Mohamed El-nasser Department of Medical Microbiology&Immunology Faculty of Medicine for Girls Al-Azhar UniversityNasr City 11754CairoEgypt

In this editorial,we discuss the article in the World Journal of *** article conducts a meta-analysis of the diagnostic accuracy of the urea breath test(UBT),a non-invasive method for detecting Helicobacter pylori(***)infection in *** is based on radionuclide-labeled *** methods,both invasive and non-invasive,are available for diagnosing *** infection,inclu-ding endoscopy with biopsy,serology for immunoglobulin titers,stool antigen analysis,and *** guidelines recommend UBTs as the primary choice for diagnosing *** infection and for reexamining after eradication *** is used to be the first choice non-invasive test due to their high accuracy,specificity,rapid results,and ***,its performance remains unaffected by the distribution of *** in the stomach,allowing a high flow of patients to be *** its widespread use,the performance characteristics of UBT have been inconsistently described and remain incompletely *** are two UBTs available with Food and Drug Administration approval:The 13C and 14C *** tests are affordable and can provide real-time *** may prefer the 13C test because it is non-radioactive,compared to 14C which uses a radioactive isotope,especially in young children and pregnant *** there was heterogeneity among the studies regarding the diagnostic accuracy of both UBTs,13C-UBT consistently outperforms the *** makes the 13C-UBT the preferred diagnostic ***,the provided findings of the meta-analysis emphasize the significance of precise considerations when choosing urea dosage,assessment timing,and measurement techniques for both the 13C-UBT and 14C-UBT,to enhance diagnostic precision.

关键词： Helicobacter pylori Urea breath test Diagnosis Diagnostic test accuracy Meta-analysis

Auto-regressive multiple-valued logic neurons with sequential Chua’s oscillator back-propagation learning for online prediction and synchronization of chaotic trajectories

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International Journal of Intelligent Computing and Cybernetics 2015年第2期8卷 102-138页

Purpose–The purpose of this paper is to examine the structural and computational potentials of a powerful class of neural networks(NNs),called multiple-valued logic neural networks(MVLNN),for predicting the behavior of phenomenological systems with highly nonlinear *** are constructed based on the integration of a number of neurons working based on the principle of multiple-valued *** possess some particular features,namely complex-valued weights,input,and outputs coded by kth roots of unity,and a continuous activation as a mean for transferring numbers from complex spaces to trigonometric spaces,which distinguish them from most of the existing ***/methodology/approach–The presented study can be categorized into three *** the first part,the authors attempt at providing the mathematical formulations required for the implementation of ARX-based MVLNN(AMVLNN).In this context,it is indicated that how the concept of ARX can be used to revise the structure of MVLNN for online ***,the stepwise formulation for the simulation of Chua’s oscillatory map and multiple-valued logic-based BP are *** an analysis,some interesting characteristics of the Chua’s map,including a number of possible attractors of the state and sequences generated as a function of time,are ***–Based on a throughout simulation as well as a comprehensive numerical comparative study,some important features of AMVLNN are *** simulation results indicate that AMVLNN can be employed as a tool for the online identification of highly nonlinear dynamic ***,the results show the compatibility of the Chua’s oscillatory system with BP for an effective tuning of the synaptic *** results also unveil the potentials of AMVLNN as a fast,robust,and efficient control-oriented model at the heart of NMPC control ***/value–This study presents two innovative ***,the structure of MVLNN is mo

关键词： Real-time systems Learning Networked control Neural nets Chaotic systems Model predictive control

A Note on the Generalized and Universal Associated Legendre Equations

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Communications in Theoretical Physics 2018年第7期69卷 19-24页

作者： Keegan L.A.Kirk Kyle R.Bryenton nasser Saad School of Mathematical & Computational Sciences University of Prince Edward Island

A class of second-order differential equations commonly arising in physics applications are considered,and their explicit hypergeometric solutions are provided. Further, the relationship with the Generalized and Universal Associated Legendre Equations are examined and established. The hypergeometric solutions, presented in this work,will promote future investigations of their mathematical properties and applications to problems in theoretical physics.

关键词： universal associated Legendre polynomials generalized associated Legendre equation hypergeo-metric series exact solutions