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1.
Heliyon ; 9(10): e20911, 2023 Oct.
Article En | MEDLINE | ID: mdl-37928395

The impact of activation energy in chemical processes, heat radiations, and temperature gradients on non-Darcian steady MHD convective Casson nanofluid flows (NMHD-CCNF) over a radial elongated circular cylinder is investigated in this study. The network of partial differential equations (PDEs) for NMHD-CCNF is developed using the modified Buongiorno framework, and the network of controlling PDEs is then transformed into ordinary differential equations (ODEs) utilizing the Von Karman method. Finally, the resulting non-linear ODEs are computed using the ND-solve approach to produce sets of data to assess the proposed model's skills, which can then be handled using the Bayesian Regularization technique of artificial neural networks (BRT-ANN). A novel stochastic computing-based application is being developed to evaluate the importance of NMHD-CCNF across a spinning disc that is radially stretched. The novelty and significance of results for better understanding, clarity, and highlighting the innovative contributions and significance of the proposed scheme. Further, to check the validity of the defined results for NMHD-CCNF, error charts, validation, and mean squared error suggestions are employed. The impact of multiple physical parameters on concentration, radial and tangential velocities, and temperature profiles is shown via tables and figures. Additionally, the results demonstrate that as the Forchheimer number, Casson nanofluid parameter, magnetic parameter, and porosity parameter are strengthened, the radial and rotational nanofluid mobility drops dramatically. The stretching parameter, on the other hand, has a parallel developmental trend. The heat generation parameter, the thermophoresis process, the thermal radiation parameter, and the Brownian motion of nanoparticles can all be increased to give thermal enhancement. On the other side, with larger estimates in thermophoresis parameters and the activation energy, there is a noticeable increase in the concentration profile.

2.
Microsc Res Tech ; 85(11): 3618-3622, 2022 Nov.
Article En | MEDLINE | ID: mdl-35942990

Ficus religiosa bark extract was chosen as a reducing agent to fabricate biogenic silver nanoparticles (AgNPs), which were used to treat chromium in synthetic wastewater. The AgNPs formed were characterized using ultraviolet-visible absorption spectroscopy (UV-vis), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The results of AgNPs characterization showed that the UV-vis spectrophotometer gave an absorbance peak for AgNPs synthesized from bark extract at 448 nm. The peaks in the XRD pattern of AgNPs synthesized from the bark extract of Ficus religiosa are associated with that of the face-centered-cubic form of metallic silver. The SEM analysis showed clear spherical morphology of AgNPs. These synthesized AgNPs were applied for the removal of chromium from synthetic wastewater. It was seen from the treatment results that above 74.8% removal efficiency was achieved. HIGHLIGHTS: Green synthesis of nanoparticles using plant extracts and their successful application in various fields has been previously studied by various researchers. Ficus religiosa bark extract was used for the synthesis of silver nanoparticles, which after characterization using ultraviolet-visible absorption spectroscopy, scanning electron microscopy, and X-ray diffraction were used to treat chromium in synthetic wastewater prepared in lab. The use of silver nanoparticles for the treatment of heavy metals in wastewater can be considered a good replacement option for the conventional treatment techniques.


Ficus , Metal Nanoparticles , Chromium , Ficus/chemistry , Metal Nanoparticles/chemistry , Plant Bark , Plant Extracts/chemistry , Reducing Agents , Silver/chemistry , Wastewater , X-Ray Diffraction
3.
Sci Rep ; 12(1): 7362, 2022 May 05.
Article En | MEDLINE | ID: mdl-35513408

The present study encompasses the application of cost effective, organo-modified bentonite material for efficient desulfurization of model oil and real fuel. For the adsorptive desulfurization of oil, dibenzothiophene (DBT) was used as model compound. Various experimental parameters (time, temperature, adsorbent-amount and DBT concentration) were thoroughly investigated. The synthesized material was characterized via X-ray diffraction (XRD), X-ray Fluorescence (XRF), Scanning electron microscopy (SEM), Energy dispersive x-ray (EDX), Thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FT-IR). The modification exhibits the increase in interlayer spacing of clay as confirmed from XRD and modified material shows interesting morphology as compared to unmodified bentonite. The results showed that > 90% of DBT removal was achieved under optimized conditions for B-BTC, B-BTB and B-DSS and > 80% for B-BEHA, for model fuel oil which are greater than unmodified clay (< 45%). Additionally, the findings from desulfurization of real fuel oil declare that 96.76% and 95.83% removal efficiency was achieved for kerosene and diesel oil respectively, at optimized conditions and fuel properties follow ASTM specifications. The obtained findings well fitted with thermodynamic, isothermal (Langmuir) with adsorption capacity (70.8 (B-BTC), 66 (B-BTB), 61.2 (B-DSS) and 55.2 (B-BEHA) in mg/g) and pseudo-second-order kinetics. In thermodynamic studies, negative sign ([Formula: see text] specifies the spontaneity whereas, [Formula: see text] endothermic and positive sign [Formula: see text] show randomness after DBT adsorption onto organoclay.

4.
Environ Res ; 212(Pt A): 113160, 2022 09.
Article En | MEDLINE | ID: mdl-35351451

For the first time, two new kinds of inorganic-organic hybrid nanomaterials (Bi2WO6@rGO and Cu-WO4@rGO) were fabricated by simple hydrothermal treatment and employed for green and efficient oxidative desulfurization of real fuel. The characterization of newly synthesized nanocomposites was performed by SEM, EDX, P-XRD, FT-IR and TGA. SEM and XRD analyses revealed well decoration of dopants (Cu-WO4 and Bi-WO3) on the surface of rGO with a crystallite size of <50 nm. The catalytic activity of both nanocatalysts was examined for model (dibenzothiophene) and real fuel (kerosene and diesel) by oxidative desulfurization route. Experimental findings revealed a high efficiency of over 90% under optimal reaction conditions of 0.1 g catalyst, 1 mL of oxidant, and 100 mg/L after 120 min at 30 °C. The major factors affecting desulfurization efficiency (time, temperature, catalyst amount, dibenzothiophene (DBT) concentration and amount of oxidant) and kinetic studies were described. The DBT removal via oxidative desulfurization followed pseudo first-order kinetics with an activation energy of 14.57 and 16.91 kJ/mol for Cu-WO4@rGO and Bi2WO6@rGO, respectively. The prepared catalysts showed promising reusability for the ODS process up to 5 times with no significant decrease in efficiency. In conclusion, the findings confirm the robustness of newly prepared nanocomposite for efficient production of sulfur-free oil.


Fuel Oils , Nanocomposites , Graphite , Kinetics , Oxidants , Oxidative Stress , Spectroscopy, Fourier Transform Infrared
5.
BMJ Case Rep ; 12(12)2019 Dec 10.
Article En | MEDLINE | ID: mdl-31826900

Congenital chloride diarrhoea is one of the rare causes of diarrhoea during infancy and it is infrequently reported throughout the world. It is an autosomal recessive condition which is more prevalent in Poland, Finland, Saudi Arabia and Kuwait while rarely reported in Pakistan. Our patient was 7.5-month-old baby boy who presented with diarrhoea since neonatal period. He had consanguineous parents. On examination, baby had distended abdomen, hypotonia and hyporeflexia. Investigations revealed hypochloremic hypokalemic metabolic alkalosis. Urinary electrolytes were normal. Stool electrolytes revealed increased stool chloride excretion that confirmed our diagnosis of congenital chloride diarrhoea. Patient was treated with intravenous fluids and electrolyte replacement, followed by oral potassium and sodium replacement. He was also started on butyrate, cholestyramine and proton-pump inhibitors. He started gaining weight during his hospital admission and is being followed up in clinic.


Diarrhea/congenital , Electrolytes/metabolism , Feces/chemistry , Metabolism, Inborn Errors/diagnosis , Potassium/metabolism , Sodium/metabolism , Consanguinity , Diarrhea/diagnosis , Diarrhea/therapy , Electrolytes/therapeutic use , Fluid Therapy , Humans , Infant , Infant, Newborn , Male , Metabolism, Inborn Errors/therapy , Pakistan , Potassium/therapeutic use , Sodium/therapeutic use , Treatment Outcome , Weight Gain/physiology
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