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A novel 2D-GO@WS2 electrochemical platform for the determination of thiram fungicide

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Journal of Environmental Sciences 2024年第2期136卷 226-236页

作者： Khouloud Abid Daniela Iannazzo Consuelo Celesti Amani Khaskhoussi Antonino Foti ramzi maalej Pietro Giuseppe Gucciardi Giovanni Neri Department of Engineering University of MessinaC.da Di DioI-98166 MessinaItaly INSTM Research Unity of MessinaItaly Laboratory of Dielectric and Photonic Materials Faculty of Sciences of SfaxSfaxUniversitySfax 3018Tunisia CNR IPCF Istituto per i Processi Chimico-Fisici viale F.Stagno D’Alcontres 37I-98156 MessinaItaly

In this paper,the determination of Thiram fungicide by a novel modified screen-printed carbon electrode(SPCE)fabricated modifying the working electrode(WE)with 2D-GO/WS2nanohybrid composites,is *** electron microscopy(SEM),Raman spectroscopy,and fluorescence analysis(PL)were used to reveal the morphological and microstructural characteristics of the 2D-GO/WS2 nanohybrids with different graphene oxide:tungsten disulphide(GO:WS_(2))*** characterization demonstrated that the 2D-WS2/GO nanohybrids having a GO:WS_(2)ratio=2:1 shows the highest electrocatalytic activity towards oxidation of *** developed sensor permits the quantification of Thiram in the linear range 0.083-0.33μM with a limit of detection(LOD)of 0.02μM,which is below the legal limits for this fungicide in drinking water or foods.

关键词： WS_(2)nanosheets Graphene Oxide(GO) Electrochemical sensor Fungicides Thiram

Judd-Ofelt parameters of the up-conversion phosphors： Er3＋ doped BaGd2ZnO5/PMMA and NaYF4/PMMA

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Journal of Rare Earths 2017年第10期35卷 964-969页

作者：胡番柳欣然陈荣荣刘延洲麦耀华 ramzi maalej 杨艳民 College of Physics Science and Technology Hebei University Baoding 071002 China College of Life Science Hebei University Baoding 071002 China Laboratoire Georessourees Materiaux Environnement et Changements Globaux Faculty of Sciences of Sfax Sfax University 3018 Sfax Tunisia

We proposed a new approach to determination of Judd-Ofelt intensity parameters of Er^（3＋） doped phosphors via their absorption spectra. To validate this approach, JO parameters of Er^（3＋） doped Ba BaGd_2ZnO_5/PMMA and NaYF_4/PMMA composites were calculated and in a good agreement with the other glass and crystal. The spontaneous radiative transition probability, branching ratio, and radiative lifetime of the optical transitions were calculated by using the Judd-Ofelt theory. Intense near-infrared emission at 1553 nm was observed under 980 nm laser diode excitation at room temperature. The samples possessing high full-width at half-maximum reach 85 nm have potential application in broadband optical amplifier.

关键词： Judd-Ofelt intensity parameters PMMA absorption cross sections near-infrared rare earths

Nonlinear unknown input observer using mean value theorem and genetic algorithm

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International Journal of Modeling, Simulation, and Scientific Computing 2019年第2期10卷 42-63页

作者： ramzi Ben Messaoud Laboratoire de Nanomateriaux et des Systemes Pour les Energies Renouvelables Centre de Recherches et des Technologies de l’Energie BP.95 Hammam Lif 2050Tunisia

In this note,we consider a new unknown input observer design for nonlinear *** main idea consists in determining the estimation error and mean value theorem parameters(β)to introduce them into proposed observer *** process is designed on the basis of mean value theorem and genetic *** stability study relies on the use of a classical quadratic Lyapunov *** observer’s gains are determined *** the validation of theoretical development proposed in this paper,we consider two practical realizations that deals with the secure communication problem.

关键词： Genetic algorithm unknown input observer nonlinear system mean value theorem state estimation

Local nonlinear unknown input observer

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控制理论与应用（英文版） 2013年第3期11卷 517-520页

作者： ramzi Ben MESSAOUD Mekki KSOURI Department of Electrical Engineering National Engineering School of TunisBox 37 1002 Tunis Tunisia

This paper proposes a new nonlinear unknown input observer. The observer design approach utilizes the first order Taylor expansion. The observer gains are then obtained by a systematic method. In this paper, we added some improvements to this method. The developed approach also can enable observer design for a large class of differentiable nonlinear systems. The necessary and sufficient conditions for the existence of the observer are given. A numerical example is given to illustrate the attractiveness and the simplicity of the new design procedure.

关键词： Unknown inputs observers Stability Nonlinear systems Robust and state estimation

A Partitioning Methodology That Optimizes the Communication Cost for Reconfigurable Computing Systems

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International Journal of Automation and computing 2012年第3期9卷 280-287页

作者： ramzi Ayadi Bouraoui Ouni Abdellatif Mtibaa Laboratory of Electronics and Microelectronics Faculty of Science of Monastir University of Monastir Department of Electrical Engineering National Engineering School of Monastir University of Monastir

This paper focuses on the design process for reconfigurable architecture. Our contribution focuses on introducing a new temporal partitioning algorithm. Our algorithm is based on typical mathematic flow to solve the temporal partitioning problem. This algorithm optimizes the transfer of data required between design partitions and the reconfiguration overhead. Results show that our algorithm considerably decreases the communication cost and the latency compared with other well known algorithms.

关键词： Temporal partitioning data flow graph communication cost reconfigurable computing systems field-programmable gate array (FPGA)

LMI solutions for H-two and H-infinity decentralized controllers applied to an aerothermic process

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控制理论与应用（英文版） 2013年第2期11卷 247-254页

作者： Najib BENNIS Mustapha ramzi Mohamed HALOUA Hussein YOULAL ENSET de Rabat Avenue de l'Arme'e Royale Madinat Al Irfane 10100 B. P. 6207 Rabat-InstitutsMorocco LASTIMI EST de sale' Universite' Mohamed V Agdal Avenue Prince sidi Mohammed B.P 227 Sale' Me'dinaMorocco EMI Avenue IbnSina B. P. 765 Agdal RabatMorocco UFR Automatique et Technologies de l'Information Faculte' des Sciences de Rabat Avenue Ibn Batouta B. P. 1014 RabatMorocco

In this paper, we present a linear matrix inequality （LMI）-based solution to implement H-two and H- infinity decentralized robust control strategies. Appropriate parametrization of optimal H-two and H-infinity controllers is used. The general formulation of the decentralized control design leads to the optimal determination of both the state feedback gains and the observer gains of the decentralized controllers. This formulation is two folds： first, a centralized controller is obtained, and then, a simplified decentralized solution is derived by optimizing only the observer gains. The mathematical determination of these gains is formulated as an LMI optimization problem that can be easily solved using LMI solvers. As an experimental evaluation of these controllers, a real time application to an aerothermic process is carried out. A continuous-time model of the process obtained with a suitable direct continuous-time identification approach is elaborated. Results illustrating the real performance obtained from the H-two and H-infinity decentralized controllers are di^cu^ge.d and comnare, d with th~ ce^ntraliTed nn^g

关键词： Parametrization approach Decentralized control H-two/H-infinity control Parameters optimization Lin-ear matrix inequality (LMI) Subspace identification Aerothermic process

Experimental evaluation of eco-friendly flocculants prepared from date palm rachis

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Journal of Environmental Sciences 2010年第10期22卷 1539-1543页

作者： ramzi Khiari Sonia Dridi-Dhaouadi Chadlia Aguir Mohamed Farouk Mhenni Research Unity of Applied Chemistry & Environment Department of Chemistry

Sodium carboxymethylcellulose （CMCNa） is an anionic water soluble polyelectrolyte widely used in many industrial sectors including food, textiles, papers, adhesives, paints, pharmaceuticals, cosmetics and mineral processing. CMCNa was produced by chemical modification of cellulose, and represents many advantages： natural, renewable, non-toxic and biodegradable. In this study, different kinds of CMCNa, prepared from an agricultural waste date palm rachis, were tested as eco-friendly flocculants for drinking water treatment and their performances as flocculants in turbidity removal enhancement were assessed. The prepared materials were characterized by the degree of substitution （DS） and polymerisation （DP）. The study of the effect of some experimental parameters on the coagulation-flocculation performance, using the prepared materials combined with aluminium sulphate （as coagulant）, showed that the best conditions for turbidity treatment were given for pH 8, coagulant dose 20 mg/L, flocculant concentration of 100 mg/L and stirring velocity （during the flocculation step） of 30 r/min. Under the optimum conditions, the turbidity removal using CMCNa, prepared from raw material, was about 95%. A comparison study between the flocculation performance of a commercial anionic flocculant （A100PWG： polyacrylamide） and that of the prepared CMCNa showed that the performance of the waste-based flocculant with a DS of 1.17 and a DP of 480 was 10% better than that achieved by the commercial one.

关键词： carboxymethylcellulose flocculants date palm rachis flocculation process

Comparative study of natural chemical for enhanced oil recovery: Focus on extraction and adsorption at quartz sand surface

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Petroleum 2023年第1期9卷 83-93页

作者： Azza Hashim Abbas ramzi A.Abd Alsaheb Jaafar Kamil Abdullah School of Mining and Geosciences Nazarbayev UniversityKazakhstan Al-khwarizmi College of Engineering University of BaghdadIraq Basrah University College of Science and Technology Iraq

In chemical enhanced oil recovery(CEOR),it is very important to utilize the excessive usage of chemicals.A great opportunity lies in adopting natural surfactants,since it is cheaper,ecosystem friendly,and less toxic than their counterpart synthetic *** the availability of natural surfactant sources,it is yet very early to decide on their ***,this research focuses on natural-saponin extracted from different raw materials available in the Middle East and their interaction with quartz-sand.A special focus was given to the adsorption isotherm models to describe the interaction with the reservoir *** raw materials were investigated are fenugreek,sugar beet leaves and *** main extraction method employed was the chemical extraction using the *** study used Uv–vis spectrometer to investigate the micellization behaviour and the consequent adsorption on *** presence of triterpenoid saponin is found dominant in all the sample,the intensity and purity differed according to the raw material *** critical micelle concentration(CMC)was at a close range of 4–5.5 wt%in all the *** highest adsorption was obtained by sugar beet leaves which is 192 g/*** is 25%and 37%higher than the Fenugreek and chickpeas,*** the salinity resulted in adsorption reduction between 2%and 56%.For the adsorption isotherms,it showed good agreement with the Langmuir model *** remarkable finding is that the sugar beet leaves heterogeneous model seems to be valid by Frendluich and Halsey isotherms.

关键词： Natural surfactants Quartz Adsorption isotherm Salinity Fenugreek Sugar beet leaves Chickpeas

Effect of β-blocker therapy in diabetic patients with stable coronary heart disease: a meta-analysis

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Journal of Geriatric Cardiology 2019年第3期16卷 291-297页

作者： Aaqib H Malik Suchith Shetty Kausik Kar ramzi El Accaoui Department of Medicine Westchester Medical Center and New York Medical CollegeValhallaNYUSA Division of Cardiology Department of MedicineUniversity of Iowa Health CareCarver College of MedicineIowaUSA

Background β-blocker (BB) therapy is a cornerstone for the treatment of coronary heart disease (CHD).The evidence of the benefit from long-term BB therapy in diabetic patients with stable CHD is *** meta-analysis summarizes the evidence relating to the BB therapy in diabetic patients with stable *** A meta-analysis was performed according to PRISMA and MOOSE guidelines for reporting of systematic reviews of observational ***,Embase,and Cochrane central were searched and two authors independently screened studies for *** quality of studies was assessed with the Newcastle Ottawa *** primary outcome of interest was all-cause mortality,cardiovascular (CV) mortality and major adverse cardiovascular events (MACE) in diabetic patients with and without BB therapy.A generic inverse variance model was used to pool odds ratio or hazards ratio from included studies to calculate the overall effect *** significance threshold was set at P-value < *** was assessed by *** Four non-randomized studies with 9515 participants were selected for the *** studies were post-hoc analyses of randomized controlled trials,and one article was an analysis of a nationally representative *** a fixed effects model,BB therapy in diabetic patients with stable CHD was found to be associated with increased risk of CV mortality,and MACE (27% and 32% respectively;P-value < 0.05) and was not associated with a reduction in all-cause mortality (HR 1.12;95% CI: 0.94–1.33;P-value = 0.22).Conclusion BB therapy in diabetic patients with stable CHD appears to be linked to higher *** randomized trials are needed in this population to confirm these findings.

关键词： β-blockers Cardiovascular mortality Diabetes MACE