32 research outputs found

    Molecular Systematic Study Of The Genus Fagonia L. In Libya

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    Molecular analyses of ten Fagonia species grown widely in the Libyan Desert have been carried to investigate the taxonomic relationship between them and to evaluate the genetic distances among them. To achieve our aim RAPD technique carried out through six arbitrary primers. Comparing with ladder DNA marker, the obtained data were computerized and analyzed using SYSTAT program. The studied species are F. arabica L., F. bruguieri   DC, F. cretica L., F.glutinosa Delile, F. indica Burm., F. microphylla Pomel, F. sinaica Boiss, F. schweinfurthii Hadidi, F. tenuifolia Steud. and F.thebaica Boiss. The genetic variability among the ten Fagonia species estimated using the DNA protein sequencing obtained from primer 1, indicates that F. indica and F. glutinosa are very closely related while F.cretica, F.microphylla  and F.arabica related to each other and gathered together in another group. The dendrograms of the six primers via UPGMA method according to RAPD finger printing gave two clusters with homology percentage 9%. The first one has F.microphylla and F.schweinfurthii at 50% similarity index. The second cluster divided into two sub-clusters. The first one included three Fagonia species (F.cretica; F.indica and F.glutinosa). The second sub-cluster subdivided into two other sub-clusters. The first one contained F.arabica and F.bruguieri at 50% similarity index. The other sub-cluster gathered F.sinaica and F.thebaica and, both species in genetic relationship with F.tenuifolia.Molecular analyses of ten Fagonia species grown widely in the Libyan Desert have been carried to investigate the taxonomic relationship between them and to evaluate the genetic distances among them. To achieve our aim RAPD technique carried out through six arbitrary primers. Comparing with ladder DNA marker, the obtained data were computerized and analyzed using SYSTAT program. The studied species are F. arabica L., F. bruguieri   DC, F. cretica L., F.glutinosa Delile, F. indica Burm., F. microphylla Pomel, F. sinaica Boiss, F. schweinfurthii Hadidi, F. tenuifolia Steud. and F.thebaica Boiss. The genetic variability among the ten Fagonia species estimated using the DNA protein sequencing obtained from primer 1, indicates that F. indica and F. glutinosa are very closely related while F.cretica, F.microphylla  and F.arabica related to each other and gathered together in another group. The dendrograms of the six primers via UPGMA method according to RAPD finger printing gave two clusters with homology percentage 9%. The first one has F.microphylla and F.schweinfurthii at 50% similarity index. The second cluster divided into two sub-clusters. The first one included three Fagonia species (F.cretica; F.indica and F.glutinosa). The second sub-cluster subdivided into two other sub-clusters. The first one contained F.arabica and F.bruguieri at 50% similarity index. The other sub-cluster gathered F.sinaica and F.thebaica and, both species in genetic relationship with F.tenuifolia

    Computational Studies on Microreactors for the Decomposition of Formic Acid for Hydrogen Production Using Heterogeneous Catalysts

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    Sustainable alternatives to conventional fuels have emerged recently, focusing on a hydrogen-based economy. The idea of using hydrogen (H2) as an energy carrier is very promising due to its zero-emission properties. The present study investigates the formic acid (FA) decomposition for H2 generation using a commercial 5 wt.% Pd/C catalyst. Three different 2D microreactor configurations (packed bed, single membrane, and double membrane) were studied using computational fluid dynamics (CFD). Parameters such as temperature, porosity, concentration, and flow rate of reactant were investigated. The packed bed configuration resulted in high conversions, but due to catalyst poisoning by carbon monoxide (CO), the catalytic activity decreased with time. For the single and double membrane microreactors, the same trends were observed, but the double membrane microreactor showed superior performance compared with the other configurations. Conversions higher than 80% were achieved, and even though deactivation decreased the conversion after 1 h of reaction, the selective removal of CO from the system with the use of membranes lead to an increase in the conversion afterwards. These results prove that the incorporation of membranes in the system for the separation of CO is improving the efficiency of the microreactor

    Experimental and Process Modelling Investigation of the Hydrogen Generation from Formic Acid Decomposition Using a Pd/Zn Catalyst

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    The use of hydrogen as a renewable fuel has attracted great attention in recent years. The decomposition of formic acid under mild conditions was investigated using a 2%Pd6Zn4 catalyst in a batch reactor. The results showed that the conversion of formic acid increases with reaction temperature and with the formic acid concentration. A process-simulation model was developed to predict the decomposition of formic acid using 2%Pd6Zn4 in a batch reactor. The model demonstrated very good validation with the experimental work. Further comparisons between the 2%Pd6Zn4 catalyst and a commercial Pd/C catalyst were carried out. It was found that the 2%Pd6Zn4 demonstrated significantly higher conversions when compared with the commercial catalyst.The authors thank London South Bank University; School of Engineering for the PhD fund that supports the work of Sanaa Hafeez

    Effects of prebiotic (lactoferrin) and diclazuril on broiler chickens experimentally infected with Eimeria tenella

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    IntroductionAvian coccidiosis presents a significant challenge to the poultry industry in Egypt, highlighting the urgent need for validating new drug targets offering promising prospects for the development of advanced anticoccidials. Although numerous reports highlight the activity of lactoferrin (LF) against various microorganisms, its potential against Eimeria has not been explored. The present study evaluated the potential anticoccidial effect of LF and diclazuril in broiler chickens experimentally infected with Eimeria tenella.MethodsA total of 100 one-day-old broiler chicks were divided into five equal groups (20 each) as follows: Group 1 (G1) served as the normal healthy control group, Group 2 (G2) consisted of chickens infected with 1 × 105 sporulated E. tenella oocysts at 14 days of age, Group 3 (G3) comprised infected chickens treated with diclazuril (0.5 mL/L in drinking water) for 3 days successively, Group 4 (G4) included infected chickens treated with LF (at a dose of 250 mg/kg of diet) from one day of age until the end of the study, and Group 5 (G5) comprised infected chickens treated with both LF and diclazuril.ResultsThe positive control group (G2) experienced significant reductions in body weight (BW), BW gain, serum glucose, lipase, amylase, total antioxidant capacity, several hematological indices, and total proteins, along with alterations in various antioxidant enzymes. Conversely, serum levels of aspartate aminotransferase (AST), Alanine aminotransferase (ALT), Alkaline phosphatases (ALP), urea, creatinine, nitric oxide, mean corpuscular volume (MCV), White blood cells (WBCs), heterophils, alpha 2, beta 1, and liver contents of malondialdehyde were elevated in this group. Moreover, higher oocyst counts and lesion scores, along with histopathological alterations, were observed in G2. Remarkably, treatment with diclazuril and/or LF demonstrated potent antioxidant and anticoccidial effects, resulting in reduced shedding of oocysts, lesion scores, and lymphocytic infiltrates in the cecum. Additionally, these treatments improved the antioxidant and immune systems in chickens and restored all histopathological changes reported in the infected non-treated group (G2).ConclusionThis study offers novel perspectives on the potential anticoccidial effects of the combination of LF and diclazuril in broiler chickens infected with E. tenella, highlighting the potential synergistic actions of LF in treating poultry coccidiosis

    Selective catalytic deoxygenation of palm oil to produce green diesel over Ni catalysts supported on ZrO2 and CeO2–ZrO2: Experimental and process simulation modelling studies

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    The selective deoxygenation of palm oil to produce green diesel has been investigated over Ni catalysts supported on ZrO2 (Ni/Zr) and CeO2–ZrO2 (Ni/CeZr) supports. The modification of the support with CeO2 acted to improve the Ni dispersion and oxygen lability of the catalyst, while reducing the overall surface acidity. The Ni/CeZr catalyst exhibited higher triglyceride (TG) conversion and yield for the desirable C15–C18 hydrocarbons, as well as improved stability compared to the unmodified Ni/Zr catalyst, with TG conversion and C15–C18 yield remaining above 85% and 80% respectively during 20 h of continuous operation at 300 oC. The high C17 yields also revealed the dominance of the deCOx (decarbonylation/decarboxylation) pathway. A fully comprehensive process simulation model has been developed to validate the experimental findings in this study, and a very good validation with the experimental data has been demonstrated. The model was then further utilised to investigate the effects of temperature, H2 partial pressure, H2/oil feed ratio and LHSV. The model predicted that maximum triglyceride conversion was attainable at reaction conditions of 300 °C temperature, 30 bar H2 partial pressure, H2/oil of 1000 cm3/cm3 feed ratio and 1.2 h−1 LHSV.MAG and NDC gratefully acknowledge that this researched was co-financed by Greece and the European Union (European Social Fund-ESF) through the Operational Programme “Human Resources Development, Education and Lifelong Learning” (MIS-5050170). KP and SA acknowledge the financial support from the Abu Dhabi Department of Education and Knowledge through the grant AARE-2019-233 and the support from Khalifa University through the grant RC2-2018-024. VS acknowledges the ICTS ELECMI-LMA for offering access to their instruments and expertise.Peer reviewe

    Dual application of entomopathogenic nematodes and fungi on immune and antioxidant enzymes of the greater wax moth, Galleria mellonella L.

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    Abstract Pathogenicity and immunity effects of both the entomopathogenic nematode, (Heterorhabditis zealandica) and the entomopathogenic fungus (Beauveria bassiana) on the last larval instar of the greater wax moth, Galleria mellonella L. (Lepidoptera: Pyralidae), were investigated. Both pathogens were either applied separately or in a combination. The fungus was inoculated first, followed by the nematode on time manner 0, 2, 4, and 6 days. LC50 values for both pathogens were calculated and then used for determination of the changes in immune response-mediated phenoloxidase (PO) and detoxifying enzymes glutathione S-transferase (GST) and non-specific esterase (EST) activities. The results indicated that a positive correlation was found between pathogen concentration and host mortality percentage. LC50 values were 6.49 IJs/larva for H. zealandica and 3.1 × 102 conidia/ml for B. bassiana. Synergistic interactions were found in all combined applications. The degree of synergism increased (reaching 100% mortality), when the nematode was applied 2 days post-fungal infection. PO activity increased significantly (p < 0.05) in a time-dependent manner post-B. bassiana infection. In contrary, the combination of H. zealandica + B. bassiana or H. zealandica alone produced a significant suppressive effect on PO activity over time. GST activity increased significantly (p < 0.05) in 36 h, then decreased at 48 h post-combined application, while the fungal infection enhanced significantly GST activity in time-dependent manner than the control and other treatments. EST activity increased significantly (p < 0.05) in both combined application and the single nematode infection than the single fungal infection, which increased during the initial period only. The increased mortality rates and suppression of phenoloxidase and glutathione S-transferase enzymes, following the combined application suggests a strong synergistic effect between both pathogens. It could be concluded that the tested combined pathogens are compatible element for integrated pest management

    Fuel production using membrane reactors: a review

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    Population growth has led to higher consumption of fossil fuel, and subsequently to a major increase of greenhouse gases emissions to the atmosphere, thus inducing global warming. Fossil fuel supplies are depleting, and the price of these fuels is increasing. Moreover, there are concerns about related emissions of toxic pollutants such as sulphur dioxide and aromatic hydrocarbons. Here, we review alternative fuel technologies. We focus on how membrane reactors improve the existing production processes of renewable fuels. Advantages and environmental benefits of membrane reactors are compared to the conventional techniques. Membrane reactors have been applied successfully to improve biodiesel, hydrogen and Fischer–Tropsch synthesis. Membranes help the conversion of products, whilst shifting the equilibrium of the reaction and reducing undesired by-products. Membrane reactors also overcome immiscibility issues that hinder conventional reactor processes. Overall, membrane reactors reduce cost and energy needed for the treatment of wastewater from fuel production.Funding text The authors would like to thank London South Bank University, School of Engineering, for the PhD funding support

    Recent progress on sonochemical production for the synthesis of efficient photocatalysts and the impact of reactor design

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    Sonochemical-assisted synthesis has flourished recently for the design of photocatalysts. The main power used is ultrasound that allows the nanomaterials shape and size modification and control. This review highlights the effect in formation mechanism by ultrasound application and the most common photocatalysts that were prepared via sonochemical techniques. Moreover, the challenge for the suitable reactor design for the synthesis of materials or for their photocatalytic evaluation is discussed since the most prominent reactor systems, batch, and continuous flow, has both advantages and drawbacks. This work summarises the significance of sonochemical synthesis for photocatalytic materials as a green technology that needs to be further investigated for the preparation of new materials and the scale up of developed reactor systems to meet industrial needs

    Modelling of packed bed and coated wall microreactors for methanol steam reforming for hydrogen production

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    A Computational Fluid Dynamics (CFD) study has been conducted to assess the performance of packed bed and coated wall microreactors for the steam reforming of methanol with a CuO/ZnO/Al2O3 based catalyst (BASF F3-01). The results obtained were compared to experimental data from the literature to assess the validity and robustness of the models, and a good validation has been obtained. The performance of the packed bed and coated wall microreactors is similar at a constant reforming temperature. It was found that methanol conversion is enhanced with increasing temperature, residence time, steam to methanol ratio, and catalyst coating thickness. Furthermore, internal and external mass transfer phenomena were investigated using the models, and it was found that there were no internal and external mass transfer resistances for this reactor configuration. Further studies demonstrated that larger catalyst pellet sizes led to the presence of internal mass transfer resistance, which in turn causes lower methanol conversions. The CFD models have exhibited a sound agreement with the experimental data, hence they can be used to predict the steam reforming of methanol in microreactors

    Computational fluid dynamics (CFD) and reaction modelling study of bio-oil catalytic hydrodeoxygenation in microreactors

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    A computational fluid dynamics (CFD) model was derived and validated in order to investigate the hydrodeoxygenation reaction of 4-propylguaiacol, which is a lignin-derived compound present in bio-oil. A 2-D packed bed microreactor was simulated using a pre-sulphided NiMo/Al2O3 solid catalyst in isothermal operation. A pseudo-homogeneous model was first created to validate the experimental results from the literature. Various operational parameters were investigated and validated with experimental data, such as temperature, pressure and liquid flow rate, and it was found that the CFD findings were in very good agreement with the results from the literature. The model was then upgraded to that of a detailed multiphase configuration, and phenomena such as internal and external mass transfer limitations were investigated, as well as reactant concentrations on the rate of 4-propylguaiacol. Both models were in agreement with the experimental data, and therefore confirm their ability for applications related to the prediction of the behaviour of bio-oil compound hydrodeoxygenation
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