Electrophoretic deposition of graphene oxide on carbon brush as bioanode for microbial fuel cell operated with real wastewater

Microbial fuel cell (MFC) is a promising technology for simultaneous wastewater treatment and energy harvesting. The properties of the anode material play a critical role in the performance of the MFC. In this study, graphene oxide was prepared by a modified hummer's method. A thin layer of graphene oxide was incorporated on the carbon brush using an electrophoretic technique. The deoxygenated graphene oxide formed on the surface of the carbon brush (RGO-CB) was investigated as a bio-anode in MFC operated with real wastewater. The performance of the MFC using the RGO-CB was compared with that using plain carbon brush anode (PCB). Results showed that electrophoretic deposition of graphene oxide on the surface of carbon brush significantly enhanced the performance of the MFC, where the power density increased more than 10 times (from 33 mWm^?2 to 381 mWm^?2). Although the COD removal was nearly similar for the two MFCs, i.e., with PCB and RGO-CB; the columbic efficiency significantly increased in the case of RGO-CB anode. The improved performance in the case of the modified electrode was related to the role of the graphene in improving the electron transfer from the microorganism to the anode surface, as confirmed from the electrochemical impedance spectroscopy measurements.     

Integrated standalone hybrid solar PV,fuel cell and diesel generator power system for battery or supercapacitor storage systems in Khorfakkan,United Arab Emirates

Renewable energy resources play a very important rule these days to assist the conventional energy systems for doing its function in the UAE due to high greenhouse gas (GHG) emissions and energy demand. In this paper, the analysis and performance of integrated standalone hybrid solar PV, fuel cell and diesel generator power system with battery energy storage system (BESS) or supercapacitor energy storage system (SCESS) in Khorfakkan city, Sharjah were presented. HOMER Pro software was used to model and simulate the hybrid energy system (HES) based on the daily energy consumption for Khorfakkan city. The simulation results show that using SCESS as an energy storage system will help the performance of HES based on the Levelized cost of energy (LCOE) and greenhouse gas (GHG) emissions. The HES with SCESS has renewable fraction (68.1%) and 0.346 $/kWh LCOE. The HES meets the annual AC primary load of the city (13.6 GWh) with negligible electricity excess and with an unmet electrical load of 1.38%. The reduction in GHG emissions for HES with SCESS was 83.2%, equivalent to saving 814,428 gallons of diesel.     

FexCo1−x-doped titanium oxide nanotubes as effective photocatalysts for hydrogen extraction from ammonium phosphate

Theoretically, tri-ammonium phosphate (NH₄)₃PO₄ embeds considerable amount of hydrogen. Typically, the expected hydrogen release from this cheap and stable material is 73.83 mmol/g_salt if a proper catalyst is exploited in the hydrolysis reaction. In this study Fe_xCo_1?x-doped titanium oxide nanotubes are introduced as an efficient photocatalyst under solar radiation. The introduced modified titanium oxide nanotubes have been prepared in two successive steps. First, Na-doped TiO₂ nanotubes were synthesized by hydrothermal treatment in presence of 10 N NaOH solution at 160 °C for 16 h. Then, doping by the proposed metals was carried out by ion exchange process in a microwave oven. X-ray photoelectron microscopy (XPS) and transmission electron microscopy (TEM) confirmed the success of the doping process and the nanotubular morphology, respectively. Study the photo characteristics indicated that the proposed metal doping shifted the band gap from UV to the visible light region as the estimated band gap energies for the as-prepared and doped nanotubes were 3.4 and 2.1 eV, respectively. Moreover, distinct enhancement for the visible light absorption capacity was observed. Accordingly, a distinguished improvement in the photocatalytic activity toward tri-ammonium phosphate hydrolysis was observed. However, the two metals content has a strong influence on the amount of the obtained hydrogen per gram of tri-ammonium phosphate salt. Numerically, the maximum obtained hydrogen was 4.0, 11.2, 11.2, 11.6, 13.4, 16.5, 17.4, 13.4 and 9.8 mmol/g_salt for the pristine TiO₂, and Fe_xCo_1?x-doped TiO₂ with x = 1, 0.8, 0.6, 0.5, 0.4, 0.3, 0.2, and 0.0, respectively.     

Transition metal nanoparticles doped carbon paper as a cost-effective anode in a microbial fuel cell powered by pure and mixed biocatalyst cultures

The poor wettability and high cost of the carbonaceous electrodes materials prohibited the practical applications of microbial fuel cells (MFCs) on large scale. Here, a novel nanoparticles of metal sheathed with metal oxide is electrodeposited on carbon paper (CP) to introduce as high-performance anodes of microbial fuel cell (MFC). This thin layer of metal/metal oxide significantly enhance the microbial adhesion, the wettability of the anode surface and decrease the electron transfer resistance. The investigation of the modified CP anodes in an air-cathode MFCs fed by various biocatalyst cultures shows a significant improving in the MFC performance. Where, the generated power and current density was 140% and 210% higher as compared to the pristine CP. Mixed culture of exoelectrogenic microorganism in wastewater exhibited good performance and generated higher power and current density compared to yeast as pure culture. The excellent capacitance with a distinctive nanostructure morphology of the modified-CP open an avenues for practical applications of MFCs.     

Fuzzy-modeling with Particle Swarm Optimization for enhancing the production of biodiesel from Microalga

Biodiesel is one of the promising energy sources that could replace petroleum oil in the near future. Microalgae is occupying a distinguished position among the promising sources for biodiesel production. Enhancement of the lipids production during the pretreatment is a key factor for the biodiesel production. High-pressure homogenizer is a better pretreatment procedure to enhance the lipid extraction from microalgae. In this research, a robust model of biodiesel system using fuzzy logic is built based on the experimental data for biodiesel system. Then, Particle Swarm Optimization (PSO) optimizer is applied for determining the best operating parameters of biodiesel system. The decision variables used in the optimization process are; pressure, number of passes, and reaction time that maximizes the percentage of recovery lipids of biodiesel. A comparison study was carried out between the optimized results thought PSO algorithm and those obtained by the experimental results and the optimized results through the Response Surface Methodology (RMS). Results demonstrated that using the proposed optimization methodology is significantly better than RSM, a nearly 78.7% increase in lipids extraction could be achieved according to the current model.     

Impact of gamma irradiation on virgin styrene butadiene rubber blended with ultrasonically devulcanized waste rubber

This investigation focused on the opportunity of devulcanizing waste Rubber (WR) by ultrasonication to study the possibility of utilized as an added substance to replace with styrene‐butadiene rubber (SBR) in preparation process with the final aim of preparation new composites. The present work expects to compare the ultrasonic technique and the previous work on devulcanization by mechano‐chemical method. The influence of the ultrasonication treatment on the WR was explored by Fourier transform infrared, thermogravimetric analysis, scanning electron microscopy analysis revealed that ultrasonication was observed to be the best factor impacting the devulcanization procedure, this procedure suggests that use of specific levels of ultrasonic waves to the vulcanized rubber with a specific aim to accomplish a particular breaking of compound connections: scission of C‐S and S‐S bonds without break carbon–carbon (C‐C) bonds. Various blends of devulcanized WR with SBR was treatments with gamma ray then investigated and compared with find out the rubber giving the highest compatibility for compounding and revulcanization. In addition, a comparison of these results was made with the ones of raw SBR rubber compound. POLYM. ENG. SCI., 59:807–813, 2019. © 2019 Society of Plastics Engineers     

Behavior analysis in Arabic social media

International Journal of Speech Technology - Social media has allowed all individuals, organizations, and businesses to share their opinions, ideas, and inclinations with others. These opinions...     

Catalytic activity of yeast extract in biofuel cell

It was revealed that the dry powder yeast extract (YE) has the ability to act as a biocatalyst as well as a mediator in a biofuel cell. The yeast extract, from Nihon Pharmaceutical Co., Ltd., was used as a biocatalyst in an open air cathode biofuel cell containing phosphate buffer for glucose oxidation. The anode medium with only the YE showed an immediate activity by producing a current and delivering power depending on its concentration. By adding glucose to the anode medium, the anode potential decreased with time to -0.2?V vs. normal hydrogen electrode (NHE), and produced a higher power compared to that without glucose. The biofuel cell produced an open circuit voltage (OCV) as high as 1?V.     

Experimental evaluation of haptic data communication with prediction

The transmission of haptic data is relatively challenging in multimedia communication. In this research study, the methods are presented for exploiting the properties of human haptic perception for data reduction of haptic data transmission. Packet-switched communication of haptic data is characterized by high packet rates on the communication channel. The quality of the internet-based haptic tele-control/tele-presence systems is highly dependent on the quality of the communication channel between the operator and the remote site, and on the delay jitter in the data exchange. The proposed research work is evaluated experimentally using a Geomagic Touch (previously PHANTOM Sensable Omni) haptic device with a sphere as a virtual model. Four experiments were conducted to evaluate the proposed research study. In the first experiment the JND Weber’s law is applied on sent force values only, while in the second experiment, the force calculation algorithm has been modified to include human movement velocity. The third experiment discusses the use of JND on the sent velocity values. The evaluation of the human’s perception shows that the proposed modification to the basic dead-band approach highly reduces the number of sent packets with minimal disturbance in haptic feeling. Further enhancements using prediction techniques have also been introduced in the fourth experimental evaluation. The linear predictions are added to the above proposed reduction methods. Combining the dead-band approach with a fast, configurable and accurate prediction algorithm enables a significant reduction in the amount of data sent across the network. The reduction is estimated to be 85%, while preserving the original data structure.