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San copolymer membranes with ion exchangers for Cu(Ⅱ)removal from synthetic wastewater by electrodialysis

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Journal of Environmental Sciences 2015年第9期27卷 27-37页

作者： Simona Caprarescu Mihai Cosmin Corobea Violeta Purcar Catalin ilie Spataru Raluca Ianchis Gabriel Vasilievici Zina Vuluga "Politehnica"University of Bucharest Faculty of Applied Chemistry and Materials Science Department of Inorganic ChemistryPhysical Chemistry and ElectrochemistryCalea Grivitei no.132 010737 Bucharest Romania National Research and Development Institute for Chemistry and Petrochemistry-ICECHIM Polymer DepartmentSplaiul Independenteino.202 060021 Bucharest Romania

Heterogeneous membranes were obtained by using styrene-acrylonitrile copolymer（SAN）blends with low content of ion-exchanger particles（5 wt.%）. The membranes obtained by phase inversion were used for the removal of copper ions from synthetic wastewater solutions by electrodialytic separation. The electrodialysis was conducted in a three cell unit, without electrolyte recirculation. The process, under potentiostatic or galvanostatic control, was followed by p H and conductivity measurements in the solution. The electrodialytic performance,evaluated in terms of extraction removal degree（rd） of copper ions, was better under potentiostatic control then by the galvanostatic one and the highest（over 70%） was attained at8 V. The membrane efficiency at small ion-exchanger load was explained by the migration of resin particles toward the pores surface during the phase inversion. The prepared membranes were characterized by various techniques i.e. optical microscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis and differential thermal analysis and contact angle measurements.

关键词： SAN copolymer Membrane Ion exchange Copper ions Electrodialysis Wastewater treatment

Satellite Communications Integration with Terrestrial Networks

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China Communications 2018年第8期15卷 22-38页

作者： Adam Kapovits Marius-lulian Corici ilie-Daniel Gheorghe-Pop Anastasius Gavras Frank Burkhardt Thomas Schlichter Stefan Covaci Eurescom GmbH Heidelberg 69123Germany Fraunhofer Institute for Open Communication Systems FOKUS Berlin 10589Germany Fraunhofer Institute for Integrated Circuits IIS Erlangen 91058Germany Technische Universitat Berlin Berlin 10623Germany

In this paper we evaluate the feasibility of seamless and efficient integration of terrestrial communication systems with satellite networks. This aspect is considered by standardisation bodies such as ETSI [1], 5 G-PPP [2] and 3 GPP [3]. A comprehensive system is designed and implemented in an emulation prototype, including standard 3 GPP LTE core network functionality [4] with its different layers: networking, data forwarding, control, management and monitoring and is validated through performance measurements. This work is a technical feasibility study of extending terrestrial communication systems with satellite networks as backhaul, increasing the energy efficiency, network robustness during natural disasters as well as being an alternative for peak-time data forwarding of the terrestrial communication services. Due to its global coverage property, terrestrial-satellite integration provides an obvious extension of communication services towards isolated and remote areas and an alternative for rural or highly distributed/highly mobile enterprise networks.

关键词： network convergence application sector requirements experimental validation

Urban avifauna distribution explained by road noise in an Eastern European city

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Avian Research 2022年第4期13卷 445-453页

作者： Alfred-Stefan Cicort-Lucaciu Hanem-Vera Keshta Paula-Vanda Popovici David Munkacsi ilie-Catalin Telcean Carmen Gache Department of Biology Faculty of Informatics and SciencesUniversity of Oradea1 Universitații Str.410087OradeaBihor CountyRomania Independent Researcher 2 Alexandru Roman Str.415200BeiușBihor CountyRomania “înv.Galgau Iosif”Secondary School 61 Pagaia417063Boianu MareBihor CountyRomania “Miskolczy Karoly”Secondary School 197 Mișca417183ChișlazBihor CountyRomania “Kazinczy Ferenc”Secondary School 602 Simian417545SimianBihor CountyRomania “Toldy”Secondary School 26 Sannicolau de Munte417441SacuieniBihor CountyRomania “Mihail Eminescu”National College 18 Roman Ciorogariu Str.410017OradeaBihor CountyRomania Technological High School No.1 48 de Jos Str.Cadea417436SacuieniBihor CountyRomania Department of Biology Faculty of Biology“Alexandru Ioan Cuza”University11A Bd.Carol I Str.700505IașiIași CountyRomania

In Eastern Europe,efforts are being made for road infrastructure development,as this area has not yet reached the level of that in the *** noise negatively affects birds,especially in urban ***,seven green spaces from an Eastern European city were monitored,which were selected according to the urbanization gradient and the hydrographic peculiarities of the *** correlation between species richness and human population density,urban mobility,or road noise was *** three factors together explained over 99%of species richness distribution in habitats and during study *** noise was the strongest predictor and the most negative influencer of bird *** correlations were higher when we also considered the variability of species in habitats over time,instead of the total species richness of a habitat,as it expresses more accurately the impact of noise on the presence of *** presence of species has decreased from one habitat to another along the urbanization gradient,from the edge of the city to the center,both in the case of terrestrial and aquatic green *** most central park differed significantly from the other terrestrial green spaces in the *** the same time,no significant differences were registered between the aquatic habitats or the rest of the terrestrial *** ideal mitigation measure in this case would be that there are no roads in the immediate vicinity of green ***,if this is not possible(as in the case of all the existing green spaces in a city),we discuss/recommend placing noise barriers at the edge of green spaces or high-speed roads.

关键词： Road noise Urban green spaces Urbanization gradient

Reducing Stochastic Discrete Models of Biochemical Networks

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Applied Mathematics 2021年第5期12卷 449-469页

作者： Samaneh Gholami Silvana ilie Department of Mathematics Ryerson University Toronto Canada

Biochemical systems have numerous practical applications, in particular to the study of critical intracellular processes. Frequently, biochemical kinetic models depict cellular processes as systems of chemical reactions. Many biological processes in a cell are inherently stochastic, due to the existence of some low molecular amounts. These stochastic fluctuations may have a great effect on the biochemical system’s behaviour. In such cases, stochastic models are necessary to accurately describe the system’s dynamics. Biochemical systems at the cellular level may entail many species or reactions and their mathematical models may be non-linear and with multiple scales in time. In this work, we provide a numerical technique for simplifying stochastic discrete models of well-stirred biochemical systems, which ensures that the main properties of the original system are preserved. The proposed technique employs sensitivity analysis and requires solving an optimization problem. The numerical tests on several models of practical interest show that our model reduction strategy performs very well.

关键词： Stochastic Simulation Algorithm Stochastic Biochemical Kinetics Sensitivity Analysis Model Reduction Methods

Effective Finite-Difference Techniques for Estimating Sensitivities for Stochastic Biochemical Systems

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Applied Mathematics 2022年第11期13卷 878-895页

作者： Fauzia Jabeen Silvana ilie Department of Mathematics Ryerson University Toronto Canada

Cellular environments are in essence stochastic, owing to the random character of the biochemical reaction events in a single cell. Stochastic fluctuations may substantially contribute to the dynamics of systems with small copy numbers of some biochemical species. Then, stochastic models are indispensable for properly portraying the behaviour of the system. Sensitivity analysis is one of the central tools for studying stochastic models of cellular dynamics. Here, we propose some finite-difference strategies for estimating parametric sensitivities of higher-order moments of the system state for stochastic discrete biochemical kinetic models. To reduce the variance of the sensitivity estimator, we employ various coupling techniques. The advantages of the proposed methods are illustrated in several models of biochemical systems of practical relevance.

关键词： Stochastic Simulation Algorithm Stochastic Biochemical Kinetics Sensitivity Analysis

A Modified Inhomogeneous Stochastic Simulation Algorithm to Model Reactive Boundary Conditions

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Journal of Applied Mathematics and Physics 2021年第8期9卷 1870-1882页

作者： A. Sayyidmousavi S. ilie Department of Mathematics Ryerson University Toronto Canada

The present study proposes a stochastic simulation scheme to model reactive boundaries through a position jump process which can be readily implemented into the Inhomogeneous Stochastic Simulation Algorithm by modifying the propensity of the diffusive jump over the reactive boundary. As compared to the literature, the present approach does not require any correction factors for the propensity. Also, the current expression relaxes the constraint on the compartment size allowing the problem to be solved with a coarser grid and therefore saves considerable computational cost. The modified algorithm is then applied to simulate three reaction-diffusion systems with reactive boundaries.

关键词： Reactive Boundary Stochastic Simulation Algorithm Reaction-Diffusion Systems

Simplifying Stochastic Mathematical Models of Biochemical Systems

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Applied Mathematics 2013年第1期4卷 248-256页

作者： Silvana ilie Samaneh Gholami Department of Mathematics Ryerson University Toronto Canada

Stochastic modeling of biochemical reactions taking place at the cellular level has become the subject of intense research in recent years. Molecular interactions in a single cell exhibit random fluctuations. These fluctuations may be significant when small populations of some reacting species are present and then a stochastic description of the cellular dynamics is required. Often, the biochemically reacting systems encountered in applications consist of many species interacting through many reaction channels. Also, the dynamics of such systems is typically non-linear and presents multiple time-scales. Consequently, the stochastic mathematical models of biochemical systems can be quite complex and their analysis challenging. In this paper, we present a method to reduce a stochastic continuous model of well-stirred biochemical systems, the Chemical Langevin Equation, while preserving the overall behavior of the system. Several tests of our method on models of practical interest gave excellent results.

关键词： Stochastic Modeling Sensitivity Analysis Model Reduction Techniques Chemical Langevin Equation

Automatic Simulation of the Chemical Langevin Equation

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Applied Mathematics 2013年第1期4卷 235-241页

作者： Silvana ilie Monjur Morshed Department of Mathematics Ryerson University Toronto Canada

Biochemical systems have important practical applications, in particular to understanding critical intra-cellular processes. Often biochemical kinetic models represent cellular processes as systems of chemical reactions, traditionally modeled by the deterministic reaction rate equations. In the cellular environment, many biological processes are inherently stochastic. The stochastic fluctuations due to the presence of some low molecular populations may have a great impact on the biochemical system behavior. Then, stochastic models are required for an accurate description of the system dynamics. An important stochastic model of biochemical kinetics is the Chemical Langevin Equation. In this work, we provide a numerical method for approximating the solution of the Chemical Langevin Equation, namely the derivative-free Milstein scheme. The method is compared with the widely used strategy for this class of problems, the Milstein method. As opposed to the Milstein scheme, the proposed strategy has the advantage that it does not require the calculation of exact derivatives, while having the same strong order of accuracy as the Milstein scheme. Therefore it may be used for an automatic simulation of the numerical solution of the Chemical Langevin Equation. The tests on several models of practical interest show that our method performs very well.

关键词： Stochastic Biochemical Kinetics Chemical Langevin Equation Derivative-Free Milstein Method

Invariant subspaces,exact solutions and stability analysis of nonlinear water wave equations

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Journal of Ocean Engineering and Science 2020年第1期5卷 35-40页

作者： K.Hosseini M.Inc M.Shafiee M.ilie A.Shafaroody A.Yusuf M.Bayram Department of Mathematics Rasht BranchIslamic Azad UniversityRashtIran Department of Mathematics Science FacultyFirat University23119 ElazigTurkey Young Researchers and Elite Club Rasht BranchIslamic Azad UniversityRashtIran Department of Mathematics Federal University Dutse7156 JigawaNigeria Department of Computer Engineering Istanbul Gelisim UniversityIstanbulTurkey

The key purpose of the present research is to derive the exact solutions of nonlinear water wave equations(NLWWEs)in oceans through the invariant subspace scheme(ISS).In this respect,the NLWWEs which describe specific nonlinear waves are converted to a number of systems of ordinary differential equations(ODEs)such that the resulting systems can be efficiently handled by computer algebra *** an accomplishment,the performance of the well-designed ISS in extracting a group of exact solutions is formally *** the end,the stability analysis for the NLWWE is investigated through the linear stability scheme.

关键词： Nonlinear water wave equations Invariant subspace scheme Exact solutions Stability analysis.