This work presents linear and nonlinear control strategies applied to a grid-connected multiple-source renewable energy system (wind and photovoltaic), in order to extract the maximum power and to ...enhance the control of the active and reactive powers. A new robust control strategy known as the active disturbance rejection control (ADRC) is proposed and applied to the hybrid renewable energy system (HRES), and it is based on the extended state observer (ESO) which allows us to estimate the internal and external disturbances such as modeling errors and parameter variations. The studied system consists of two conversion chains which are linked via a common DC bus and interconnected to the grid through a voltage source inverter (VSI); the first chain consists of a PV system and a DC-DC boost converter, and the second chain consists of a direct-driven wind turbine, permanent magnetic synchronous generator (PMSG), and of a AC/DC rectifier converter. The extraction of maximum power from the PV system and the wind energy conversion system is ensured by using the voltage based perturb and observe (VPO) and the optimal torque control (OTC) MPPT techniques, respectively. The ADRC technique is utilized to control the active and reactive powers by acting on the grid currents. In order to verify and validate the effectiveness of the proposed control strategy, a detailed model of the studied system is designed and evaluated under the MATLAB/Simulink software. The simulation results prove the effectiveness of the MPPT techniques in terms of maximum power extraction during the variation in the environmental conditions. Additionally, the regulation of active and reactive powers is ensured by ADRC, and the system is operating at a unity power factor. Moreover, it is demonstrated that the suggested strategy is efficient in terms of fast tracking and robustness to internal and external disturbances compared to the classical PI controller.
Avian influenza viruses of the H9N2 subtype continue to spread in wild birds and poultry worldwide. Infection with H9N2 avian influenza virus was detected for the first time in Morocco in January ...2016. In this study, a total of 105 organ and tracheal swab samples from 21 broiler farms in Morocco were collected from July 2016 to October 2018 for H9N2 screening. The suspicion of disease was based on severe respiratory signs such as sneezing, coughing, rales and gasping, while H9N2 virus infection was confirmed by real-time RT-PCR. Hemagglutinin (HA) genes of four isolates were amplified by conventional RT-PCR, sequenced, and aligned for phylogenetic analyses. Among the 21 flocks, 48% (10/21) were qRT-PCR positive for H9, with the cycle threshold values ranging from18.6 to 34.8. The maximum similarity in nucleotide and protein sequences (96-98%) was observed between the Moroccan viruses and an H9 virus isolated from broiler chickens in 2017 in Burkina Faso (A/chicken/BurkinaFaso/17RS93-19/2017) and from a layer chicken in the United Arab Emirates in 2015 (A/chicken/Dubai/D2506/2015). The HA genes revealed the close relationship between the four Moroccan viruses, with 97.9%-99.9% nucleotide identity. Phylogenetic analysis showed that the Moroccan viruses belonged to the G1 lineage, and likely originated from the Middle East, as previously reported in 2016.
Para desarrollar el presente trabajo se hace la descripción de un defecto anatómico de dorso nasal, secuela inmediata por resección quirúrgica de una lesión tumoral con un volumen aproximado de 5 cm. ...de diámetro, para lo cual la técnica quirúrgica planificada para su reconstrucción anatómica ha sido la utilización de un colgajo rotacional paramedial frontal; haremos una descripción de la técnica quirúrgica, las ventajas de lo escogido en comparación a otras técnicas alternativas, indicaciones y complicaciones de la técnica, resultados y seguimiento del caso. Se han descrito varias técnicas quirúrgicas para reconstruir defectos anatómicos de pirámide nasal según el sitio donde se ubique, ya que la planificación quirúrgica mucho dependerá del sitio a reconstruir y del volumen del tamaño del defecto, pudiendo utilizarse desde un cierre por primera intención, injertos libres miocutáneos o con contenido cartilaginoso, colgajos rotacionales regionales o a distancia; siendo todas técnicas debidamente descritas y desarrolladas en textos y artículos científicos referentes a la especialidad quirúrgica. Haremos la presentación del caso clínico referente a este artículo, discutiendo las diferentes alternativas de tratamiento que se pudieron haber utilizado, ventajas y desventajas de cada una de ellas en base a revisión de artículos científicos referenciales; se procederá a la presentación del caso clínico.
Se presenta el tratamiento de una sinusitis maxilar más pólipos intra maxilares de una paciente femenina de 39 años, causados por una comunicación oroantral pos extracción de órgano dental 1.6., en ...el que se utilizó el abordaje cuadrangular combinado con antrostomía lateral intranasal como alternativa para el manejo de patologías del seno maxilar, proporcionando ventajas sobre el abordaje clásico Caldwell Luc, con una mejor visibilidad del interior del seno maxilar, fácil manejo y eliminación de los tejidos patológicos y la posibilidad de reconstrucción del defecto óseo realizado.
Virusi ptičje gripe H9N2 nastavljaju se širiti u peradi i divljih ptica širom svijeta. Infekcija niskopatogenim virusom influence H9N2 prvi je put otkrivena u Maroku u siječnju 2016. godine. U ovom ...je istraživanju za probir na H9N2 prikupljeno ukupno 105 organa i obrisaka iz dušnika s 21 farme brojlera od srpnja 2016. do listopada 2018. iz različitih regija Maroka. Sumnja na bolest temeljila se na teškim respiracijskim znakovima kao što su kihanje, kašljanje, hropanje i hripanje, a infekcija virusom H9N2 potvrđena je PCR-om obrnute transkripcije u stvarnom vremenu. Sekvencije gena za hemaglutinin (HA) od četiri izolata amplificirane su pomoću RT-PCR qRT-PCR poravnane za filogenetsku i analizu sličnosti aminokiselina. Od 21 uzorka jata 48 % (10/21) bilo je pozitivno na H9 s pragom broja ciklusa u rasponu od 18,6 do 34,8. Maksimalna sličnost u nukleotidnim i proteinskim sekvencijama (96 -98 %) uočena je između marokanskih virusa i virusa H9 izoliranih iz brojlerskih pilića u 2017. u Burkini Faso (A/piletina/BurkinaFaso/17RS93-19) i od kokošjeg pileta u Ujedinjenim Arapskim Emiratima u 2015. (A/piletina/ Dubai/D2506/2015). HA geni otkrili su blisku vezu između četiriju virusa, s 97,9 % -99,9 % nukleotidnog identiteta. Filogenetska analiza pokazala je da marokanski virusi pripadaju lozi G1 i vjerojatno potječu s Bliskog istoka, kao što je objavljeno 2016. godine.
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•The clays' high efficiency favors the adsorption of toxic dyes and heavy metals.•Different methods of modifying the surface functions of natural clays affect their adsorption ...capacities remarkably.•Understanding the adsorption mechanism of emerging pollutants on the surface of clay materials is crucial.•The economic and environmental benefits of clays, as well as their ability to regenerate, indicate that they could be industrially exploitable.
The adsorption process is one of the most cost-effective methods for eliminating various types of pollutants from water. Clay minerals can be converted into biosorbents for environmental remediation. This literature review summarizes the different types of natural clays, their crystal structures, classifications, physical and chemical properties, and industrial applications. Also the main results of recent studies on the process and mechanism of adsorption on natural clay materials to eliminate heavy metals and highly emerging toxic dyes. The Langmuir and Freundlich models are the most commonly used isotherms in most previous studies. In addition, the adsorption kinetics of the majority of dyes and heavy metals using natural clays are based on the pseudo-second-order model. High adsorption capacities of 909.09 mg g−1 for synthetic dyes and 179 mg g−1 for heavy metals were observed. This review article suggests that clays can be modified by various methods to improve their adsorption efficiencies by increasing their specific surface areas. The clays' low cost and ability to regenerate show that these materials are environmentally friendly and beneficial for industrial ecology.
The challenge of the scientific community is to synthesize innovative, low-cost, and environmentally friendly membrane materials for the treatment of industrial wastewater. The objective of this work ...is the elaboration and characterization of a new flat ceramic membrane based on a natural Moroccan phengite clay by the paste casting method for microfiltration applications. The ceramic membrane was sintered from 850 °C to 1150 °C for 2 hours. The optimal membrane sintered at 1050 °C has a porosity of 34.5%, an average pore diameter of 3.9 μm, water permeability of 43.50 L/h m2 bar, mechanical strength of 26.7 MPa, and excellent chemical corrosion resistance in acidic and basic media. The performance of the optimal membrane was evaluated by frontal microfiltration of the pre-treated real wastewater (RWW3) from a local clothes washing. The obtained results show that the removal percentage of electrical conductivity, total dissolved solids, and suspended matter is 66.2%, 71.8%, and 100% respectively. The cost of preparing the ceramic membrane was estimated at 3.5 $/m2, which is cheaper compared to those commercially available. The high regeneration efficiency showed that demineralized water was able to adequately clean the fouled microfiltration membrane by 82%. The obtained filtration results are very promising and could allow the use of the membrane prepared from a locally available material as an alternative process in the treatment of various sources of industrial wastewater.
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The present research work revolves around the evaluation of the elimination of the cationic dye methylene blue (MB) from an aqueous solution by the exploitation of natural clay (TMG) from South-East ...Morocco. Several physicochemical techniques were used to characterize our TMG adsorbate, namely, X-ray diffraction, Fourier transform infrared absorption spectroscopy, differential thermal analysis, thermal gravimetric analysis, and zero charge point (pHpzc). The morphological properties and elemental composition of our material were identified using scanning electron microscopy coupled with an energy-dispersive X-ray spectrometer. The batch technique was used under different operating conditions to produce quantitative adsorption, namely, the amount of adsorbent, dye concentration, contact time, pH, and solution temperature. The maximum adsorption capacity of MB on TMG was 81.185 mg g
for a concentration of 100 mg L
MB at pH
= 6.43 (no initial adjustment of the pH-value was performed), temperature 293 K, and 1 g L
adsorbent. The adsorption data were examined by Langmuir, Freundlich, and Temkin isotherms. The Langmuir isotherm provides the best correlation with the experimental data, and the pseudo-second-order kinetic model is more appropriate for the adsorption of the MB dye. The thermodynamic study of MB adsorption indicates that the process is physical, endothermic, and spontaneous. The Box-Behnken method was applied to identify the optimal conditions for MB removal in the design of batch experiments. The parameters examined result in >99% removal. The TMG material's regeneration cycles and low cost ($0.393 per gram) show that it is both environmentally friendly and very effective for dye removal in the various textile sectors.
Wastewater textile dye treatment is a challenge that requires the development of eco-friendly technology to avoid the alarming problems associated with water scarcity and health-environment. This ...study investigated the potential of phengite clay as naturally low-cost abundant clay from Tamgroute, Morocco (TMG) that was activated with a 0.1M NaOH base (TMGB) after calcination at 850°C for 3 hours (TMGC) before its application in the Congo red (CR) anionic dye from the aqueous solution. The effect of various key operational parameters: adsorbent dose, contact time, dye concentration, pH, temperature, and the effect of salts, was studied by a series of adsorption experiments in a batch system, which affected the adsorption performance of TMG, TMGC, and TMGB for CR dye removal. In addition, the properties of adsorption kinetics, isotherms, and thermodynamics were also studied. Experimental results showed that optimal adsorption occurred at an acidic pH. At a CR concentration of 100 mg L-1, equilibrium elimination rates were 68%, 38%, and 92% for TMG, TMGC, and TMGB, respectively. The adsorption process is rapid, follows pseudo-second-order kinetics, and is best described by a Temkin and Langmuir isotherm. The thermodynamic parameters indicated that the adsorption of CR onto TMGB is endothermic and spontaneous. The experimental values of CR adsorption on TMGB are consistent with the predictions of the response surface methodology. These led to a maximum removal rate of 99.97% under the following conditions: pH =2, TMGB dose of 7g L-1, and CR concentration of 50 mg L-1. The adsorbent TMGB's relatively low preparation cost of around $2.629 g-1 and its ability to regenerate in more than 6 thermal calcination cycles with a CR removal rate of around 56.98%, stimulate its use for textile effluent treatment on a pilot industrial scale.
•Sodium hydroxide-treated phengite clay (TMGB) adsorbs Congo red dye efficiently.•The adsorption rate exceeded 92% after Box Behnken design optimization.•TMBG-CR adsorption mechanism dominated by electrostatic interactions per FTIR.•TMGB is non-toxic, low-cost ($2.629/g), eco-friendly and over 6 regeneration cycles.
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