242 research outputs found

    Optimization Of Palm Oil Mill Effluent Treatment By Applying RSM And ANN

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    AbstractThe optimization of the COD removal from palm oil mill effluent (POME) has done. The correlation of concentration and pH of POME, and Trans membrane pressure (TMP) of Reverse Osmosis (RO) membrane was optimized by response surface method using a second order polynomial model with Box Behken design consist of 17 runs. To determine whether the model was adequate for representing the experimental data; it was indicated by the ANNOVA table (p-value, lack of fit and R2 values).  The main factor influenced the COD removal was concentration and pH of POME.  The optimum conditions were determined from 3D response surface and 2D contour graphs i.e. 28.30% of POME concentration at pH 10.75 and TMP 0.69 kPa to yield 24.1372 mg/L of COD value. The results demonstrate that the response surface method effective to minimize the number of experiment. Keywords: POME; RO membrane; RSM; ANN; CO

    Charged-Higgs phenomenology in the Aligned two-Higgs-doublet model

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    The alignment in flavour space of the Yukawa matrices of a general two-Higgs-doublet model results in the absence of tree-level flavour-changing neutral currents. In addition to the usual fermion masses and mixings, the aligned Yukawa structure only contains three complex parameters, which are potential new sources of CP violation. For particular values of these three parameters all known specific implementations of the model based on discrete Z_2 symmetries are recovered. One of the most distinctive features of the two-Higgs-doublet model is the presence of a charged scalar. In this work, we discuss its main phenomenological consequences in flavour-changing processes at low energies and derive the corresponding constraints on the parameters of the aligned two-Higgs-doublet model.Comment: 46 pages, 19 figures. Version accepted for publication in JHEP. References added. Discussion slightly extended. Conclusions unchange

    Application of Response Surface Method in Reverse Osmosis Membrane to Optimize BOD, COD and Colour Removal from Palm Oil Mill Effluent

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    Palm oil mill effluent (POME) is typically non-biodegradable and has high concentration of organic matter that represented as COD, BOD and Colour values. The correlation of concentration and pH of POME, and Trans membrane pressure (TMP) of Reverse Osmosis (RO) membrane was optimized by response surface method using a second order polynomial model with central composite design (CCD) which is a part model of response surface method (RSM) in Design-Expert® software. The main limits that influenced the parameters removal i.e. concentration of POME, pH of solution and transmembrane pressure were empirically determined at laboratory level and successfully optimized using RSM. The best conditions were determined from 3D response surface and 2D contour graphs i.e. 10.05% of POME concentration at pH 3.0 and TMP 0.50 kPa to yield the last values of COD, BOD and Colour i.e. 24.1372 mg/L,  24.33 mg/L and 11.76 PtCo, respectively.  The results show that the response surface method effective to reduce the number of experiment

    Novel Graphene-Zinc Iron Oxide Composite to Enhance Ultrafiltration Membrane Performance for Water Treatment and Desalination

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    The main target of membrane technologies such as the Ultrafiltration (UF), Nanofiltration (NF) and Reverse osmosis (RO) is to produce better filtration and separation of organic and inorganic substance from water as well as for longer life of the membrane. The phase inversion method is a well-known method to fabricate UF, NF and RO membranes for different application. The UF membrane is widely used in separation of macromolecules from solution as pretreatment stage with higher efficiency in hybrid process. The UF membrane made by pure polymer showed low flux, which affect on process performance of separation. The Polysulphone (PSF) is the most common polymer used in UF membrane which a hydrophobic material is making its surface prone to fouling due to adsorptive mechanism. This limitation of UF membranes have been solved by blended with nanoparticles incorporated membranes which showed significant enhancement on permeability, surface hydrophilicity, mechanical properties and other properties such as the selectivity. The main objective of this study to modify of UF membrane by blended with new composite nano-material for higher rejection of salt and organic substances. The graphene-zinc iron oxide composite as new nano-material was synthesized by sol gel method at low temperature of preparation. The composite was characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) to show the structure, morphology and particle size of nanoparticles. Thermal decomposition was determined using thermogravimetric-differential scanning calorimetry (TGDSC). The results showed that cubic system of zinc iron oxide nanoparticles with 8 nm of crystal size was obtained using XRD. The morphology using TEM showed zinc iron oxide composite graphene as layer of nanoparticles with size lower than 10 nm which confirmed the XRD results. The novel synthesized of zinc iron oxide nanoparticles embedded in graphene incorporated into polysulfone (PSF) with 0.5 wt. % loading which significant impact on the UF membrane properties was investigated. The effect of composite additive on membrane properties was investigated in terms of permeability, hydrophilicity (contact angle), zeta potential, porosity and pore size. However, the membrane cross section, surface, EDX and mapping were also analyzed using FESEM include EDX analyzer. This composite incorporated PSF showed significant improvement in terms of surface hydrophilicity with reduction of about 25% (reduce contact angle from 82 to 62). This improvement confirms by increasing the zeta potential values and surface negatively charge of blended PSF with composite compared to pure PSF membrane. The permeability results showed that significant increased more than two times compared to pure PSF membrane. The phenomenon of permeability increasing was attributed to increase of porosity of blended membrane which becomes lower resistance of water permeation. Generally, the rate of pore production has been reported directly affected by rate of solvent and non-solvent exchange in phase inversion process. However, higher rejections of organic substances such as the dyes and humic acid as well as the salt such as Sodium sulfate (Na2SO4) were maintained using UF at low pressure. This enhancement affects on time and load of process especially when hybrid with Nanofiltration (NF) which can increase of membrane life and reduce of overall process cost. The results of this study will have bigger impact in the future for different application including for water treatment and desalination.qscienc

    Improved properties and salt rejection of polysulfone membrane by incorporation of hydrophilic cobalt-doped ZnO nanoparticles

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    In this study, the nanoparticles (NPs) of ZnO and Co2+ ions doped ZnO (doped ZnO) were incorporated into a matrix of polysulfone (PSf) membranes to enhance their surface properties prepared using a simple wet phase inversion technique. The hybrid PSf membranes were fabricated with 0.5 wt. % of ZnO and doped ZnO NPs. These membranes were characterized using XRD, TGA, FESEM-EDX, and salt rejection performance. The hydrophilicity of PSf membranes was improved by adding of ZnO and doped ZnO NPs which showed a decrease in contact angle values from 82° to 62° with an increased flux with water. Among the prepared membranes, doped ZnO NPs showed the highest salt rejection for both sodium chloride (NaCl) and sodium sulfate (Na2SO4) compared to pure PSf and PSf with ZnO NPs which confirm the improvement contact angle and water permeability. Overall, the results of this study showed that embedding a small amount of Co2+ ions doped ZnO NPs with PSf has significant potential to be applied in industrial-scale membrane applications.Scopu

    Adsorption of 4-Nitrophenol onto Iron Oxide Bentonite Nanocomposite: Process Optimization, Kinetics, Isotherms and Mechanism

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    Despite its importance in chemical industry, 4-Nitrophenol (4-NP) is a persistent organic pollutant that has serious effects on the ecosystem. In the present study, Box–Behnken design in response surface methodology was used to optimize the adsorption process parameters for the maximum 4-NP removal at 30 ℃ using Fe3O4/Bt NC. The regression model results suggested that the optimum adsorbent dosage, initial concentration, pH and contact time were 0.3182 g, 85 mg/L, 11 and 137.2 min, respectively. The regression model showed an optimum removal of 100%, while 99.5% removal was obtained from batch experiments at the optimum conditions suggested by the regression model, which confirm the model validity. The adsorption data best fitted to Freundlich isotherm model and Pseudo second-order kinetic model suggesting the existence of physical and chemical interaction between the fabricated composite and 4-NP. FTIR analysis suggested that the adsorption mechanism included an electrostatic attraction and the formation of new chemical bonds. Obtained results suggest that Fe3O4/Bt NC can be an effective adsorbent for complete 4-NP removal at the indicated optimum conditions.This research was made possible by an NPRP Grant # 10-0127-170270 from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors. The author Dina Ewis acknowledged the financial support of QNRF through the Graduate Sponsorship Research Award (GSRA) number GSRA#6-2-0516-19029.Scopu

    Annulatascus nilensis sp. nov., a new freshwater ascomycete from the River Nile, Egypt

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    Annulatascus nilensis sp. nov., from freshwater habitats in Egypt, is described, illustrated and compared to other species in the genus. Phylogenetic analyses of its LSU rDNA sequence with similar fungi placed the new species in the genus Annulatascus (Annulatascaceae, Sordariomycetidae incertae sedis). Annulatascus nilensis is characterized by immersed ascomata with an ascomatal neck oriented horizontally to the substrate surface, asci with a long, narrow stalk and massive bipartite apical ring, and 5–11-septate, hyaline ascospores surrounded by a large irregular, granular sheath that is not seen in water

    The effects of diets enriched in omega-3 polyunsaturated fatty acids on systemic vaccinia virus infection

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    Omega-3 polyunsaturated fatty acids (PUFA, n-3 fatty acids), the key components of fish and flaxseed oils, are increasingly consumed by the public because of their potential health benefits and are available by prescription for hypertriglyceridemia. However, numerous studies have shown that these compounds are immunoregulatory and immunosuppressive and thus may increase susceptibility to infection. In this study, we tested the effects of the amount of fat and the types of fatty acid in the diet on infection by vaccinia virus, an acute infection that begins in the respiratory tract and spreads by viremia to internal organs. Male C57Bl6 mice (~5 week old) were fed for 3 weeks prior to infection and continuing during infection and recovery one of the following: 1) a normal low fat (13% kcal) diet, 2) a low fat diet containing n-3 PUFAs, 3) a high fat (41% kcal) diet rich in n-3 PUFAs, 4) a high fat n-6 PUFA diet, or 5) a high fat monounsaturated diet. We found no statistically significant differences in the susceptibility of mice to viral infection, morbidity, viral organ titers, recovery time, or mortality with these diets, indicating that, over this approximately 6-week time period, dietary fats did not substantially affect responses to poxviral infection
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