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Microbial fuel cell (MFC) would be a standalone solution for clean, sustainable energy and rural electrification. It can be used in addition to wastewater treatment for bioelectricity generation. Materials chosen for the membrane and electrodes are of low cost with suitable conducting ions and electrical properties. The prime objective of the present work is to enhance redox reactions by using novel and low-cost cathode catalysts synthesized from waste castor oil. Synthesized graphene has been used as an anode, castor oil-emitted carbon powder serves as a cathode, and clay material acts as a membrane. Three single-chambered MFC modules developed were used in the current study, and continuous readings were recorded. The maximum voltage achieved was 0.36 V for a 100 mL mixture of domestic wastewater and cow dung for an anodic chamber of 200 mL. The maximum power density obtained was 7280 mW/m2. In addition, a performance test was evaluated for another MFC with inoculums slurry, and a maximum voltage of 0.78 V and power density of 34.4093 mW/m2 with an anodic chamber of 50 mL was reported. The present study’s findings show that such cathode catalysts can be a suitable option for practical applications of microbial fuel cells.
Shobha Kumbar; Dipak Jadhav; Chetan Jarali; Dhananjay Talange; Asif Afzal; Sher Khan; Mohammad Asif; Mohd. Abdullah. Enhancement in Cathodic Redox Reactions of Single-Chambered Microbial Fuel Cells with Castor Oil-Emitted Powder as Cathode Material. Materials 2021, 14, 4454 .
AMA StyleShobha Kumbar, Dipak Jadhav, Chetan Jarali, Dhananjay Talange, Asif Afzal, Sher Khan, Mohammad Asif, Mohd. Abdullah. Enhancement in Cathodic Redox Reactions of Single-Chambered Microbial Fuel Cells with Castor Oil-Emitted Powder as Cathode Material. Materials. 2021; 14 (16):4454.
Chicago/Turabian StyleShobha Kumbar; Dipak Jadhav; Chetan Jarali; Dhananjay Talange; Asif Afzal; Sher Khan; Mohammad Asif; Mohd. Abdullah. 2021. "Enhancement in Cathodic Redox Reactions of Single-Chambered Microbial Fuel Cells with Castor Oil-Emitted Powder as Cathode Material." Materials 14, no. 16: 4454.
Biodiesel is a promising renewable energy option that significantly reduces the emission of greenhouse gases and other toxic byproducts. However, a major challenge in the industrial scale production of biodiesel is the desired product purity. To this end, reactive distillation (RD) processes, which involve simultaneous removal of the byproduct during the transesterification reaction, can drive the equilibrium towards high product yield. In the present study, we first optimized the heat exchange network (HEN) for a high purity RD process leading to a 34% reduction in the overall energy consumption. Further, a robust control scheme is proposed to mitigate any feed disturbance in the process that may compromise the product purity. Three rigorous case studies are performed to investigate the effect of composition control in the cascade with the temperature control of the product composition. The cascade control scheme effectively countered the disturbances and maintained the fatty acid mono-alkyl ester (FAME) purity.
Syed Ali; Agus Arsad; Sk Hossain; Avijit Basu; Mohammad Asif. Energy Optimization and Effective Control of Reactive Distillation Process for the Production of High Purity Biodiesel. Processes 2021, 9, 1340 .
AMA StyleSyed Ali, Agus Arsad, Sk Hossain, Avijit Basu, Mohammad Asif. Energy Optimization and Effective Control of Reactive Distillation Process for the Production of High Purity Biodiesel. Processes. 2021; 9 (8):1340.
Chicago/Turabian StyleSyed Ali; Agus Arsad; Sk Hossain; Avijit Basu; Mohammad Asif. 2021. "Energy Optimization and Effective Control of Reactive Distillation Process for the Production of High Purity Biodiesel." Processes 9, no. 8: 1340.
Traditional Multi-Criteria Decision Making (MCDM) methods have now become outdated; therefore, most researchers are focusing on more robust hybrid MCDM models that combine two or more MCDM techniques to address decision-making problems. The authors attempted to create two novel hybrid MCDM systems in this paper by integrating Additive Ratio ASsessment (ARAS) with Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) and Complex PRoportional ASsessment (COPRAS). To demonstrate the ability and effectiveness of these two hybrid models i.e., TOPSIS-ARAS and COPRAS-ARAS were applied to solve a real-time robot selection problem with 12 alternative robots and five selection criteria, while evaluating the parametric importance using the CRiteria Importance Through Inter criteria Correlation (CRITIC) objective weighting estimation tool. The rankings of the robot alternatives gained from these two hybrid models were also compared to the obtained results from eight other solo MCDM tools. Although the rankings by the applied methods slightly differ from each other, the final outcomes from all of the adopted techniques are consistent enough to suggest that robot 12 is the best choice followed by robot 11, and robot 4 is the worst one among these 12 alternatives. Spearman Correlation Coefficient (SCC) also reveals that the proposed rankings derived from various methods have a strong ranking relationship with one another. Finally, sensitivity analysis was performed to investigate the effects of weight variation and to validate the robustness of the implemented MCDM approaches.
Shankha Goswami; Dhiren Behera; Asif Afzal; Abdul Razak Kaladgi; Sher Khan; Parvathy Rajendran; Ram Subbiah; Mohammad Asif. Analysis of a Robot Selection Problem Using Two Newly Developed Hybrid MCDM Models of TOPSIS-ARAS and COPRAS-ARAS. Symmetry 2021, 13, 1331 .
AMA StyleShankha Goswami, Dhiren Behera, Asif Afzal, Abdul Razak Kaladgi, Sher Khan, Parvathy Rajendran, Ram Subbiah, Mohammad Asif. Analysis of a Robot Selection Problem Using Two Newly Developed Hybrid MCDM Models of TOPSIS-ARAS and COPRAS-ARAS. Symmetry. 2021; 13 (8):1331.
Chicago/Turabian StyleShankha Goswami; Dhiren Behera; Asif Afzal; Abdul Razak Kaladgi; Sher Khan; Parvathy Rajendran; Ram Subbiah; Mohammad Asif. 2021. "Analysis of a Robot Selection Problem Using Two Newly Developed Hybrid MCDM Models of TOPSIS-ARAS and COPRAS-ARAS." Symmetry 13, no. 8: 1331.
Countries globally are focusing on alternative fuels to reduce the environmental pollution. An example is biodiesel fuel, which is leading the way to other technologies. In this research, the methyl esters of castor oil were prepared using a two-step transesterification process. The respective properties of the castor oil (Ricinus Communis) biodiesel were estimated using ASTM standards. The effect of performance and emission on diesel engines was noted for four various engine loads (25, 50, 75, and 100%), with two different blends (B5 and B20) and at two different engine speeds (1500 and 2000 rpm). The study determined that B5 and B20 samples at 1500 rpm engine speed obtained the same power, but diesel fuel generated greater control. The power increased at 2000 rpm for B5 samples, but B20 samples, as well as diesel, were almost the same values. In the 40–80% range, load and load values were entirely parallel for each load observed from the engine performance of the brake power in all samples.
Munimathan Arunkumar; Vinayagam Mohanavel; Asif Afzal; Thanikodi Sathish; Manickam Ravichandran; Sher Khan; Nur Abdullah; Muhammad Bin Azami; Mohammad Asif. A Study on Performance and Emission Characteristics of Diesel Engine Using Ricinus Communis (Castor Oil) Ethyl Esters. Energies 2021, 14, 4320 .
AMA StyleMunimathan Arunkumar, Vinayagam Mohanavel, Asif Afzal, Thanikodi Sathish, Manickam Ravichandran, Sher Khan, Nur Abdullah, Muhammad Bin Azami, Mohammad Asif. A Study on Performance and Emission Characteristics of Diesel Engine Using Ricinus Communis (Castor Oil) Ethyl Esters. Energies. 2021; 14 (14):4320.
Chicago/Turabian StyleMunimathan Arunkumar; Vinayagam Mohanavel; Asif Afzal; Thanikodi Sathish; Manickam Ravichandran; Sher Khan; Nur Abdullah; Muhammad Bin Azami; Mohammad Asif. 2021. "A Study on Performance and Emission Characteristics of Diesel Engine Using Ricinus Communis (Castor Oil) Ethyl Esters." Energies 14, no. 14: 4320.
Steam generation and utilization are needed in many industries and home appliances with, specific requirements. Though there are numerous categories of boilers available for steam generation, this analysis concentrated on the water tube boiler since it produces more steam and offers better safety measures. Taguchi techniques are considered in this entire research work completed through design of experiments (DOE). Orthogonal array L16 is selected to examine the steam generation with four process parameters and four levels. Selected process parameters are namely temperature of feed water (°C), the pressure of feed water (bar), cold water supply (liters), and boiler drum pressure (bar). The response of this study is the as steam generation to since increasing the steam is a target of this investigation. The experimental value of the steam generation is compared with the desired range; most of the response values are within the predicted value. Further, the superheated steam temperature and pressure analysis were also carried out. The maximum steam generation is achieved as 84.31 L; registered in the 15th run of the experiment.
T. Sathish; V. Mohanavel; Asif Afzal; M. Arunkumar; M. Ravichandran; Sher Afghan Khan; Parvathy Rajendran; Mohammad Asif. Advancement of steam generation process in water tube boiler using Taguchi design of experiments. Case Studies in Thermal Engineering 2021, 27, 101247 .
AMA StyleT. Sathish, V. Mohanavel, Asif Afzal, M. Arunkumar, M. Ravichandran, Sher Afghan Khan, Parvathy Rajendran, Mohammad Asif. Advancement of steam generation process in water tube boiler using Taguchi design of experiments. Case Studies in Thermal Engineering. 2021; 27 ():101247.
Chicago/Turabian StyleT. Sathish; V. Mohanavel; Asif Afzal; M. Arunkumar; M. Ravichandran; Sher Afghan Khan; Parvathy Rajendran; Mohammad Asif. 2021. "Advancement of steam generation process in water tube boiler using Taguchi design of experiments." Case Studies in Thermal Engineering 27, no. : 101247.
The use of flow pulsation as an effective assisted fluidization technique has been suggested in a number of applications, such as drying of food and pharmaceutical products, dry beneficiation of coal, and deagglomeration of nanopowders, owing mainly to its cost-effectiveness and ease of implementation. The efficacy of this technique is, however, greatly affected by the frequency of pulsation since it controls the collapse dynamics of the fluidized bed. In this study, using ultrafine hydrophilic nanosilica with strong agglomeration tendencies, the pulsation frequency was controlled to allow only partial collapse of the bed between two successive pulsations while the global and local dynamics in different bed regions were carefully monitored. Besides the usual advantages associated with assisted fluidization techniques, such as lower minimum fluidization velocity, higher bed expansion, and elimination of bed non-homogeneities, the continuous and intense solid motion imparted by the partial bed collapse caused a more substantial increase in the overall pressure drop than the one obtained with the conventional unassisted fluidization. The results of the frequency domain analysis highlighted the fact that the effect of pulsation event was felt differently in different regions of the bed depending upon the amplitude of the pulsation. These results were further corroborated by the similarity analysis.
Syed Sadiq Ali; S. K. Safdar Hossain; Mohammad Asif. Dynamics of partially collapsing pulsed fluidized bed. The Canadian Journal of Chemical Engineering 2021, 1 .
AMA StyleSyed Sadiq Ali, S. K. Safdar Hossain, Mohammad Asif. Dynamics of partially collapsing pulsed fluidized bed. The Canadian Journal of Chemical Engineering. 2021; ():1.
Chicago/Turabian StyleSyed Sadiq Ali; S. K. Safdar Hossain; Mohammad Asif. 2021. "Dynamics of partially collapsing pulsed fluidized bed." The Canadian Journal of Chemical Engineering , no. : 1.
Neurotransmitter Dopamine and purine-metabolism-derived Uric acid are quintessential compositions of the human body. The presence of these two substances to the proper extent is highly needed for a fit human being. In this paper we have synthesized Cu nanoparticle supported on reduced graphene oxide ([email protected]) by simple, cost-effective method, characterized the material by different techniques like Atomic Force Microscopy (AFM), UV-Visible spectroscopy, Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD) and Raman spectroscopy. Cyclic voltammetry (CV) and Electrochemical impedance spectroscopy (EIS) have been performed to confirm the effectivity of this material as an electrochemical sensor of Dopamine (DA) and Uric acid (UA).
Nadavala Siva Kumar; Ebrahim H. Al-Ghurabi; Mohammad Asif; Mourad Boumaza. Retrieving and morphological portrayal of Cu-nanoparticle impregnated reduced graphene oxide ([email protected]) electrochemical bio-sensor. Sensors and Actuators A: Physical 2021, 329, 112826 .
AMA StyleNadavala Siva Kumar, Ebrahim H. Al-Ghurabi, Mohammad Asif, Mourad Boumaza. Retrieving and morphological portrayal of Cu-nanoparticle impregnated reduced graphene oxide ([email protected]) electrochemical bio-sensor. Sensors and Actuators A: Physical. 2021; 329 ():112826.
Chicago/Turabian StyleNadavala Siva Kumar; Ebrahim H. Al-Ghurabi; Mohammad Asif; Mourad Boumaza. 2021. "Retrieving and morphological portrayal of Cu-nanoparticle impregnated reduced graphene oxide ([email protected]) electrochemical bio-sensor." Sensors and Actuators A: Physical 329, no. : 112826.
Herein, we report the synthesis of between SnO2 QDs /AgVO3 nanoribbons/g-C3N4 nanosheets of ternary photocatalytic systems for the production of H2 through light irradiation. The SnO2/AgVO3/g-C3N4 photocatalyst was successfully produced by using the hydrothermal process. The structural characterizations of the samples revealed the successful formation of ternary heterostructures where SnO2, AgVO3 and g-C3N4 (quantum dots/nanoribbons/nanosheets) 0D/1D/2D structures make a good interface with each other. The fabricated heterostructures of AgVO3/g-C3N4 and SnO2/AgVO3/g-C3N4 photocatalytic structures performed enriched photocatalytic performance for H2 production over that of the pristine g-C3N4, AgVO3 and SnO2 photocatalysts. The AgVO3/g-C3N4 and SnO2 /AgVO3/g-C3N4 of photocatalysts were found to produce H2 of around 17,000 μmol g-1 and 77,000 μmol g-1, respectively, which is much 4.5 times greater than that of AgVO3/g-C3N4 photocatalyst. Moreover, the photodegradation behaviours of prepared catalysts were studied with the dye (rhodamine B, RhB) under light irradiation. The ternary composite SnO2/AgVO3/g-C3N4 performed photodegradation of RhB in 50 min. The higher photocatalytic activity for the ternary photocatalysts is predominantly due to the effective charge separation at the perfect interface formation amid SnO2 and AgVO3/g-C3N4.
Ganesh Koyyada; Nadavala Siva Kumar; Ebrahim H. Al-Ghurabi; Mohammad Asif; Koduru Mallikarjuna. Enhanced solar-driven photocatalytic performance of a ternary composite of SnO2 quantum dots//AgVO3 nanoribbons//g-C3N4 nanosheets (0D/1D/2D) structures for hydrogen production and dye degradation. Environmental Science and Pollution Research 2021, 28, 31585 -31595.
AMA StyleGanesh Koyyada, Nadavala Siva Kumar, Ebrahim H. Al-Ghurabi, Mohammad Asif, Koduru Mallikarjuna. Enhanced solar-driven photocatalytic performance of a ternary composite of SnO2 quantum dots//AgVO3 nanoribbons//g-C3N4 nanosheets (0D/1D/2D) structures for hydrogen production and dye degradation. Environmental Science and Pollution Research. 2021; 28 (24):31585-31595.
Chicago/Turabian StyleGanesh Koyyada; Nadavala Siva Kumar; Ebrahim H. Al-Ghurabi; Mohammad Asif; Koduru Mallikarjuna. 2021. "Enhanced solar-driven photocatalytic performance of a ternary composite of SnO2 quantum dots//AgVO3 nanoribbons//g-C3N4 nanosheets (0D/1D/2D) structures for hydrogen production and dye degradation." Environmental Science and Pollution Research 28, no. 24: 31585-31595.
Unlike conventional fluidization of micron-sized particles, the hydrodynamics of ultrafine nanopowders is controlled by their agglomerates, which show strong segregation pattern along the bed height. This aspect was carefully investigated in this study by carrying out collapse experiments in a low-frequency pulsed fluidized bed. Unlike previous studies, the inlet flow was modified with the help of four-way valve configuration to eliminate the inlet flow spike. The region-wise collapse dynamics was monitored by recording pressure transients along the height of the fluidized bed while double drainage deaeration strategy, termed modified dual drainage (MDD), was employed. The size of agglomerates in the different bed regions were evaluated and compared with the conventional single drainage (SD) and dual drainage (DD) deaeration configurations using two-way and three-way solenoid valves. The elimination of the flow spike with MDD helped to suppress the size-based segregation of agglomerates, thereby resulting in faster and smoother bed collapse.
Syed Sadiq Ali; Agus Arsad; Mohammad Asif. Effect of modified inlet flow strategy on the segregation phenomenon in pulsed fluidized bed of ultrafine particles: A collapse bed study. Chemical Engineering and Processing - Process Intensification 2020, 159, 108243 .
AMA StyleSyed Sadiq Ali, Agus Arsad, Mohammad Asif. Effect of modified inlet flow strategy on the segregation phenomenon in pulsed fluidized bed of ultrafine particles: A collapse bed study. Chemical Engineering and Processing - Process Intensification. 2020; 159 ():108243.
Chicago/Turabian StyleSyed Sadiq Ali; Agus Arsad; Mohammad Asif. 2020. "Effect of modified inlet flow strategy on the segregation phenomenon in pulsed fluidized bed of ultrafine particles: A collapse bed study." Chemical Engineering and Processing - Process Intensification 159, no. : 108243.
Nanosilica is widely used in various applications, with its market expected to grow over USD 5 billion by 2025. The fluidized bed technology, owing to its intimate contact and efficient mixing of phases, is ideally suited for the large scale processing of powders. However, the bulk processing and dispersion of ultrafine nanosilica using the fluidized bed technology are critically affected by the interparticle forces, such that the hydrophilic nanosilica shows agglomerate bubbling fluidization (ABF), while the hydrophobic nanosilica undergoes agglomerate particulate fluidization (APF). This study carried out a detailed investigation into the fluidization hydrodynamic of the hydrophobic nanosilica by monitoring the region-wise dynamics of the fluidized bed subjected to a regular step change of fixed duration in the gas velocity. The gas flow was controlled using a mass controller operated with an analog output signal from a data acquisition system. The analog input data were acquired at the sampling rate of 100 Hz and analyzed in both time and temporal frequency domains. The effect of velocity transients on the bed dynamics was quickly mitigated and appeared as lower frequency events, especially in regions away from the distributor. Despite the apparent particulate nature of the fluidization, strong hysteresis was observed in both pressure drop and bed expansion. Moreover, the fully fluidized bed’s pressure drop was less than 75% of the theoretical value even though the bed appeared to free from non-homogeneities. Key fluidization parameters, e.g., minimum fluidization velocity (Umf) and the agglomerate size, were evaluated, which can be readily used in the large scale processing of nanosilica powders using fluidized bed technology.
Ebrahim H. Al-Ghurabi; Mohammad Asif; Nadavala Siva Kumar; Sher Afghan Khan. Fluidization Dynamics of Hydrophobic Nanosilica with Velocity Step Changes. Applied Sciences 2020, 10, 8127 .
AMA StyleEbrahim H. Al-Ghurabi, Mohammad Asif, Nadavala Siva Kumar, Sher Afghan Khan. Fluidization Dynamics of Hydrophobic Nanosilica with Velocity Step Changes. Applied Sciences. 2020; 10 (22):8127.
Chicago/Turabian StyleEbrahim H. Al-Ghurabi; Mohammad Asif; Nadavala Siva Kumar; Sher Afghan Khan. 2020. "Fluidization Dynamics of Hydrophobic Nanosilica with Velocity Step Changes." Applied Sciences 10, no. 22: 8127.
The processing of fine and ultrafine particles using a fluidized bed is challenging in view of their unpredictable hydrodynamic behavior due to interparticle forces. The use of assisted fluidization techniques in such cases can be effective in improving the bed hydrodynamics. This work investigates the dynamics of pulsed fluidized bed of ultrafine nanosilica subjected to square-wave flow pulsations. The pulse duration used in this study is sufficient to allow the complete collapse of the pulsed fluidized bed between two consecutive flow pulsations. The proposed pulsation strategy is carefully implemented using electronic mass flow controllers with the help of analog output signals from data acquisition system. Given that the different regions of the fluidized bed exhibit varying dynamics, which together contribute to overall bed dynamics, the bed transients in the upper, central, and lower regions of the fluidized bed are monitored using several sensitive pressure transducers located along the height of the bed. The effect of the flow pulsation on the hydrodynamics of the fluidized bed is rigorously characterized. A significant reduction in the minimum fluidization velocity was obtained and an increase in the bed homogeneity was observed due to flow pulsations. The frequency domain analysis of the signals clearly delineated the frequency of the various events occurring during the fluidization.
Mohammad Asif; Ebrahim H. Al-Ghurabi; Abdelhamid Ajbar; Nadavala Siva Kumar. Hydrodynamics of Pulsed Fluidized Bed of Ultrafine Powder: Fully Collapsing Fluidized Bed. Processes 2020, 8, 807 .
AMA StyleMohammad Asif, Ebrahim H. Al-Ghurabi, Abdelhamid Ajbar, Nadavala Siva Kumar. Hydrodynamics of Pulsed Fluidized Bed of Ultrafine Powder: Fully Collapsing Fluidized Bed. Processes. 2020; 8 (7):807.
Chicago/Turabian StyleMohammad Asif; Ebrahim H. Al-Ghurabi; Abdelhamid Ajbar; Nadavala Siva Kumar. 2020. "Hydrodynamics of Pulsed Fluidized Bed of Ultrafine Powder: Fully Collapsing Fluidized Bed." Processes 8, no. 7: 807.
The demand for eco-friendly renewable energy resources as energy storage and management devices is increased due to their high-power density and fast charge/discharge capacity. Recently, supercapacitors have fascinated due to their fast charge–discharge capability and high-power density along with safety. Herein, the authors present the synthesis of 3D-hierarchical peony-like ZnCo2O4 structures with 2D-nanoflakes by a hydrothermal method using polyvinylpyrrolidone. The reaction time was modified to obtain two samples (ZCO-6h and ZCO-12h) and the rest of the synthesis conditions were the same. The synthesized structures were systematically studied through various techniques: their crystalline characteristics were studied through XRD analysis, their morphologies were inspected through SEM and TEM, and the elemental distribution and oxidation states were studied by X-ray photoelectron spectroscopy (XPS). ZCO-12h sample has a larger surface area (55.40 m2·g−1) and pore size (24.69 nm) than ZCO-6h, enabling high-speed transport of ions and electrons. The ZCO-12h electrode showed a high-specific capacitance of 421.05 F·g−1 (31.52 C·g−1) at 1 A·g−1 and excellent cycle performance as measured by electrochemical analysis. Moreover, the morphologic characteristics of the prepared hierarchical materials contributed significantly to the improvement of specific capacitance. The excellent capacitive outcomes recommend the 3D-ZnCo2O4 hierarchical peony-like structures composed of 2D-nanoflakes as promising materials for supercapacitors with high-performance.
Gutturu Rajasekhara Reddy; Nadavala Siva Kumar; Borelli Deva Prasad Raju; Gnanendra Shanmugam; Ebrahim H. Al-Ghurabi; Mohammad Asif. Enhanced Supercapacitive Performance of Higher-Ordered 3D-Hierarchical Structures of Hydrothermally Obtained ZnCo2O4 for Energy Storage Devices. Nanomaterials 2020, 10, 1206 .
AMA StyleGutturu Rajasekhara Reddy, Nadavala Siva Kumar, Borelli Deva Prasad Raju, Gnanendra Shanmugam, Ebrahim H. Al-Ghurabi, Mohammad Asif. Enhanced Supercapacitive Performance of Higher-Ordered 3D-Hierarchical Structures of Hydrothermally Obtained ZnCo2O4 for Energy Storage Devices. Nanomaterials. 2020; 10 (6):1206.
Chicago/Turabian StyleGutturu Rajasekhara Reddy; Nadavala Siva Kumar; Borelli Deva Prasad Raju; Gnanendra Shanmugam; Ebrahim H. Al-Ghurabi; Mohammad Asif. 2020. "Enhanced Supercapacitive Performance of Higher-Ordered 3D-Hierarchical Structures of Hydrothermally Obtained ZnCo2O4 for Energy Storage Devices." Nanomaterials 10, no. 6: 1206.
Low-frequency flow pulsations were utilized to improve the hydrodynamics of the fluidized bed of hydrophilic ultrafine nanosilica powder with strong agglomeration behavior. A gradual fluidization of unassisted fluidized bed through stepwise velocity change was carried out over a wide range of velocities followed by a gradual defluidization process. Bed dynamics in different regions of the fluidized bed were carefully monitored using fast and sensitive pressure transducers. Next, 0.05-Hz square-wave flow pulsation was introduced, and the fluidization behavior of the pulsed fluidized bed was rigorously characterized to delineate its effect on the bed hydrodynamics by comparing it with one of the unassisted fluidized bed. Flow pulsations caused a substantial decrease in minimum fluidization velocity and effective agglomerate diameter. The frequencies and amplitudes of various events in different fluidized bed regions were determined by performing frequency domain analysis on real-time bed transient data. The pulsations and their effects promoted deagglomeration and improved homogeneity of the pulsed fluidized bed.
Ebrahim H. Al-Ghurabi; Mohammed Shahabuddin; Nadavala Siva Kumar; Mohammad Asif. Deagglomeration of Ultrafine Hydrophilic Nanopowder Using Low-Frequency Pulsed Fluidization. Nanomaterials 2020, 10, 388 .
AMA StyleEbrahim H. Al-Ghurabi, Mohammed Shahabuddin, Nadavala Siva Kumar, Mohammad Asif. Deagglomeration of Ultrafine Hydrophilic Nanopowder Using Low-Frequency Pulsed Fluidization. Nanomaterials. 2020; 10 (2):388.
Chicago/Turabian StyleEbrahim H. Al-Ghurabi; Mohammed Shahabuddin; Nadavala Siva Kumar; Mohammad Asif. 2020. "Deagglomeration of Ultrafine Hydrophilic Nanopowder Using Low-Frequency Pulsed Fluidization." Nanomaterials 10, no. 2: 388.
In the present study, a novel choice of sheath materials for drawing long superconducting MgB2 wire by using the powder-in-tube technique (PIT) is reported. This would eliminate the need for an intermediate strain-relieving annealing process and would reduce the time and cost of fabrication. Our strategy involved the use of a composite sheath instead of a sheath made of a single material. The relatively inert Fe constituted the inner sheath around the MgB2 powder while the Cu—which is capable of efficient heat dissipation—was used as the outer sheath. Important mechanical properties of the wire such as elastic modulus, ultimate tensile strength, yield strength, hardness, and microstructure were carefully studied at different stages of the drawing process using tensile and microhardness tests. To clearly delineate the effect of Cu cladding on the ductile behavior of the iron sheath, another MgB2 wire with only an Fe sheath was prepared; its mechanical properties were measured and compared with those of the composite Cu–Fe-sheathed MgB2 wire. After a few drawing steps, the composite Cu–Fe-sheathed wire showed a lower elastic modulus and tensile strength than those of its Fe sheath counterpart. While both types of wires showed an increase in hardness as the drawing process progressed, the composite-sheath wire consistently showed a lower hardness than that of its counterpart, implying its lower susceptibility to fracture; it can therefore be safely drawn to small diameters without the need for intermediate annealing during the wire drawing process.
Niyaz Ahamad Madhar; Mohammed Shahabuddin; Monis Luqman; Taha Bilal; Nasser S. Alzayed; Mohammad Asif. Effect of Cu Cladding on the Mechanical Properties of Iron Sheath Material in the Drawing of Superconducting MgB2 Wires. Metals 2019, 9, 1190 .
AMA StyleNiyaz Ahamad Madhar, Mohammed Shahabuddin, Monis Luqman, Taha Bilal, Nasser S. Alzayed, Mohammad Asif. Effect of Cu Cladding on the Mechanical Properties of Iron Sheath Material in the Drawing of Superconducting MgB2 Wires. Metals. 2019; 9 (11):1190.
Chicago/Turabian StyleNiyaz Ahamad Madhar; Mohammed Shahabuddin; Monis Luqman; Taha Bilal; Nasser S. Alzayed; Mohammad Asif. 2019. "Effect of Cu Cladding on the Mechanical Properties of Iron Sheath Material in the Drawing of Superconducting MgB2 Wires." Metals 9, no. 11: 1190.
Decoration of 2D semiconductor structures with heterogeneous metal quantum dots has attracted considerable attention due to advanced optical, electrical, and catalytic properties that result from the large surface-to-volume ratio associated with these structures. Herein, we report on silver quantum dot decorated 2D SnO2 nanoflakes for the photocatalytic abatement of water effluents, the synthesis of which was achieved through a straightforward and mild hydrothermal procedure. The photocatalysts were systematically investigated using UV–Vis, XRD, electron microscopy (SEM, HR-TEM), EDX, XPS and FTIR. The photocatalytic activity of the nanostructures was evaluated for the abatement of water pollutant rhodamine B (RhB), under light irradiation. The mild hydrothermal synthesis (100 °C) proved highly efficient for the production of large scale Ag quantum dot (QD)/SnO2 nanoflakes for a novel photocatalytic application. The decoration of SnO2 with Ag QDs significantly enhances the synergetic charge transfer, which diminishes the photo-induced electron-hole reunion. Moreover, the plasmonic effect from Ag QDs and 2D-SnO2 structures acts as an electron tank to collect the photo-induced electrons, generating a Schottky barrier between the SnO2 structures and quantum dots. Overall, this resulted in a facile and efficient degradation of RhB, with a rate double that of pristine SnO2.
Nadavala Siva Kumar; Mohammad Asif; T. Ranjeth Kumar Reddy; Gnanendra Shanmugam; Abdelhamid Ajbar. Silver Quantum Dot Decorated 2D-SnO2 Nanoflakes for Photocatalytic Degradation of the Water Pollutant Rhodamine B. Nanomaterials 2019, 9, 1536 .
AMA StyleNadavala Siva Kumar, Mohammad Asif, T. Ranjeth Kumar Reddy, Gnanendra Shanmugam, Abdelhamid Ajbar. Silver Quantum Dot Decorated 2D-SnO2 Nanoflakes for Photocatalytic Degradation of the Water Pollutant Rhodamine B. Nanomaterials. 2019; 9 (11):1536.
Chicago/Turabian StyleNadavala Siva Kumar; Mohammad Asif; T. Ranjeth Kumar Reddy; Gnanendra Shanmugam; Abdelhamid Ajbar. 2019. "Silver Quantum Dot Decorated 2D-SnO2 Nanoflakes for Photocatalytic Degradation of the Water Pollutant Rhodamine B." Nanomaterials 9, no. 11: 1536.
The present work discusses the adsorptive removal of a phenolic pollutant, i.e., 2,4,6-trichlorophenol (TCP), using low cost untreated agricultural waste pine cone powder (PCP). The present biosorbent was thoroughly characterized with the help of FTIR, SEM, XRD, and CHN analysis. The presence of amine (-NH2), hydroxyl (-OH) and carbonyl (C=O) functional groups was detected by the FTIR analysis. The important biosorption factors like agitation time, biomass dosage, initial adsorbate concentration, and the initial pH were examined by batch studies. The biosorption kinetic process was fast, reaching equilibrium in 75 min. The experimental kinetic data revealed an excellent agreement with the pseudo second order (PSO) model. On the other hand, the Langmuir isotherm model best described the equilibrium data with the maximum biosorption capacity (qmax) of 243.90 mg/g. These values are better than the adsorption capacities of most agro-based untreated adsorbents previously reported in the literature. Owing to fast removal rates and high biosorption capacity, PCP can be used for cost-effective treatment of TCP from aqueous streams.
Nadavala Siva Kumar; Mohammad Asif; Anesh Manjaly Poulose; Madala Suguna; Mansour I. Al-Hazza. Equilibrium and Kinetic Studies of Biosorptive Removal of 2,4,6-Trichlorophenol from Aqueous Solutions Using Untreated Agro-Waste Pine Cone Biomass. Processes 2019, 7, 757 .
AMA StyleNadavala Siva Kumar, Mohammad Asif, Anesh Manjaly Poulose, Madala Suguna, Mansour I. Al-Hazza. Equilibrium and Kinetic Studies of Biosorptive Removal of 2,4,6-Trichlorophenol from Aqueous Solutions Using Untreated Agro-Waste Pine Cone Biomass. Processes. 2019; 7 (10):757.
Chicago/Turabian StyleNadavala Siva Kumar; Mohammad Asif; Anesh Manjaly Poulose; Madala Suguna; Mansour I. Al-Hazza. 2019. "Equilibrium and Kinetic Studies of Biosorptive Removal of 2,4,6-Trichlorophenol from Aqueous Solutions Using Untreated Agro-Waste Pine Cone Biomass." Processes 7, no. 10: 757.
We developed a novel yet commercially viable strategy of synthesizing superior high-TC superconducting composites by dispersing fully exfoliated carbon nanotubes (CNTs) uniformly throughout the grain of CNT-MgB2 composites. First, we optimized the amount of the surfactant required to produce a highly stable and homogeneous colloidal suspension of CNTs. This amount was found to be 1/8th of the amount of CNTs. Second, we prepared a homogeneous CNT-B mixture by adding amorphous nano-boron (B) to the colloidal CNT suspension. Next, two different MgB2 synthesis routes were explored. In one case, we mixed an appropriate amount of Mg in the CNT-B mixture and carried out sintering. In the second case, the CNT-B mixture was heat treated at 500 °C, prior to mixing with Mg and sintering to form CNT-MgB2. Both kinds of samples were rigorously characterized to obtain an insight into their properties. The direct synthesis route shows a clear exfoliation and uniform dispersion of CNTs with a critical current density (JC) of 104 A/cm2 at 3.5 T and 20 K, which is useful for the application in magnetic resonance imaging MRI magnet operating with a cryogen free cooler. Our JC(H) result is 10 times higher than that of the pure sample. By contrast, the performance of the sample subjected to heat processing before sintering was severely compromised given the formation of MgO. Despite its simplicity, the direct synthesis route can be used for the cost-effective fabrication of CNT-MgB2 superconducting composites.
Mohammed Shahabuddin; Niyaz Ahamad Madhar; Nasser S. Alzayed; Mohammad Asif. Uniform Dispersion and Exfoliation of Multi-Walled Carbon Nanotubes in CNT-MgB2 Superconductor Composites Using Surfactants. Materials 2019, 12, 3044 .
AMA StyleMohammed Shahabuddin, Niyaz Ahamad Madhar, Nasser S. Alzayed, Mohammad Asif. Uniform Dispersion and Exfoliation of Multi-Walled Carbon Nanotubes in CNT-MgB2 Superconductor Composites Using Surfactants. Materials. 2019; 12 (18):3044.
Chicago/Turabian StyleMohammed Shahabuddin; Niyaz Ahamad Madhar; Nasser S. Alzayed; Mohammad Asif. 2019. "Uniform Dispersion and Exfoliation of Multi-Walled Carbon Nanotubes in CNT-MgB2 Superconductor Composites Using Surfactants." Materials 12, no. 18: 3044.
Biodiesel is a promising energy substitute of fossil fuels since it is produced from renewable and biodegradable sources. In the present work, reactive distillation (RD) process is designed and simulated using Aspen Plus process simulator to produce biodiesel of high purity through esterification reaction. The simultaneous reaction and separation in same unit enhances the biodiesel yield and composition in RD process. Two flowsheets are proposed in present work. In the first flowsheet, the unreacted methanol is recycled back to reactive distillation column. Biodiesel with 99.5 mol% purity is obtained in product stream while the byproduct stream comprises 95.2 mol% water, which has to be treated further. In the second flowsheet, a part of methanol recycle is split and purged. In this case, the biodiesel composition in product stream is 99.7 mol% whereas water composition is 99.9 mol% in byproduct stream, which can be reused for other process without treatment.
Syed Sadiq Ali; Mohammad Asif; Avijit Basu. Design and simulation of high purity biodiesel reactive distillation process. PJCT 2019, 21, 1 -7.
AMA StyleSyed Sadiq Ali, Mohammad Asif, Avijit Basu. Design and simulation of high purity biodiesel reactive distillation process. PJCT. 2019; 21 (3):1-7.
Chicago/Turabian StyleSyed Sadiq Ali; Mohammad Asif; Avijit Basu. 2019. "Design and simulation of high purity biodiesel reactive distillation process." PJCT 21, no. 3: 1-7.
Sound-assisted fluidization has of late gained a significant research focus as a potential assisted fluidization technique for improving the hydrodynamics of solids that exhibit cohesive and non-homogeneous fluidization behavior. This study investigated the dynamics of a bed subjected to acoustic perturbations at different frequencies during the sound-assisted fluidization of a hydrophilic nanopowder with strong agglomeration behavior. The bed pressure transients were carefully monitored using sensitive pressure transducers in different sections of the bed over a wide range of velocities using ambient air as the fluidizing gas. Both fluidization and defluidization dynamics were investigated by varying the velocity in small steps using electronic mass flow controllers connected to a data acquisition system. In addition to the resonance frequency of 220 Hz, acoustic vibrations of 200 and 150 Hz frequency were also investigated to clearly delineate the effect of resonant frequency on the bed response. Our results clearly suggest that operation of sound-assisted fluidization at the resonant frequency greatly enhances its effectiveness.
Ebrahim H. Al-Ghurabi; Syed Sadiq Ali; Sulaiman M. Alfadul; Mohammed Shahabuddin; Mohammad Asif. Experimental investigation of fluidized bed dynamics under resonant frequency of sound waves. Advanced Powder Technology 2019, 30, 2812 -2822.
AMA StyleEbrahim H. Al-Ghurabi, Syed Sadiq Ali, Sulaiman M. Alfadul, Mohammed Shahabuddin, Mohammad Asif. Experimental investigation of fluidized bed dynamics under resonant frequency of sound waves. Advanced Powder Technology. 2019; 30 (11):2812-2822.
Chicago/Turabian StyleEbrahim H. Al-Ghurabi; Syed Sadiq Ali; Sulaiman M. Alfadul; Mohammed Shahabuddin; Mohammad Asif. 2019. "Experimental investigation of fluidized bed dynamics under resonant frequency of sound waves." Advanced Powder Technology 30, no. 11: 2812-2822.
In the present study, we report the fluidization behavior of ultrafine nanopowder using the assisted fluidization technique of particle mixing, which was further superimposed with the pulsation of the inlet gas flow to the fluidized bed. The powder selected in the present study was hydrophilic nanosilica, which shows strong agglomeration behavior leading to poor fluidization hydrodynamics. For particle mixing, small proportions of inert particles of Geldart group A classification were used. The inlet gas flow to the fluidized bed was pulsed with a square wave of frequency 0.1 Hz with the help of a solenoid valve controlled using the data acquisition system (DAQ). In addition to the gas flow rate to the fluidized bed, pressure transients were carefully monitored using sensitive pressure transducers connected to the DAQ. Our results indicate a substantial reduction in the effective agglomerate size as a result of the simultaneous implementation of the assisted fluidization techniques of particle mixing and flow pulsation.
Syed Sadiq Ali; Avijit Basu; Sulaiman M. Alfadul; Mohammad Asif. Nanopowder Fluidization Using the Combined Assisted Fluidization Techniques of Particle Mixing and Flow Pulsation. Applied Sciences 2019, 9, 572 .
AMA StyleSyed Sadiq Ali, Avijit Basu, Sulaiman M. Alfadul, Mohammad Asif. Nanopowder Fluidization Using the Combined Assisted Fluidization Techniques of Particle Mixing and Flow Pulsation. Applied Sciences. 2019; 9 (3):572.
Chicago/Turabian StyleSyed Sadiq Ali; Avijit Basu; Sulaiman M. Alfadul; Mohammad Asif. 2019. "Nanopowder Fluidization Using the Combined Assisted Fluidization Techniques of Particle Mixing and Flow Pulsation." Applied Sciences 9, no. 3: 572.