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.     

Optimize adaptive media playout using dynamic fuzzy logic control for video streaming

Multimedia Tools and Applications - Adaptive Media Playout (AMP) controls adapt playout rate to prevent buffer outage and to reduce delay in playout. Most AMP techniques use buffer fullness or its...     

Transport of pollutant in shallow flows: A space–time CE/SE scheme

This paper focuses on implementation of space–time CE/SE scheme for computing the transport of a passive pollutant by a flow. The flow model comprises of the Saint-Venant system of shallow water equations and the pollutant propagation is described by a transport equation. The one-dimensional and two-dimensional flow equations are numerically investigated using the CE/SE scheme. A number of test problems are presented to check the accuracy and efficiency of the proposed scheme. The results of CE/SE scheme are compared with the central scheme. Both the schemes are found to be in close agreement. However, our proposed CE/SE scheme accurately captures shocks and discontinuous profiles.     

Characterization of boride coatings on a ductile cast iron

In this work, the EN-GJS-400-15 cast iron was pack-borided in a powder mixture composed of 5% B₄C, 5% NaBF₄ and 90% SiC at the three temperatures: 900, 950 and 1000°C for 2, 4 and 6 h, respectively. The pack-borided EN-GJS-400-15 cast iron was characterized by the following experimental techniques: optical microscopy, XRD analysis and Microhardness Vickers tester. The growth kinetics of boride layers was also investigated. As a consequence, the boron activation energy was found to be 212.28 kJ mol^–1 for the EN-GJS-400-15 cast iron. Based on a regression model, a useful equation was derived to estimate the boride layer thickness as a function of the boriding parameters (time and temperature). A good agreement was then obtained between the predicted values of boride layers thicknesses and those measured experimentally. In addition, an iso-thickness diagram was proposed to be used as a simple tool to select the boride layers thicknesses according to the potential applications of EN-GJS-400-15 cast iron in industry.     

Ultraviolet radiation aging impact on physicochemical properties of crosslinked polyethylene cable insulation

This article deals within the study of the effect of artificial radiations on physical and chemical properties of the crosslinked polyethylene (XLPE) material, widely used for manufacturing high-voltage cables. Within this framework, several experimental tests, using essential characterization techniques, were performed to study XLPE behavior under ultraviolet (UV) aging. Attenuated total reflection Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, X-ray diffraction, and scanning electron microscopy were thus carried out to identify the main structure changes of the material before and after exposure to UV. In addition, appearance changes and DC (Direct Current) volume resistivity were evaluated. The obtained results showed that UV radiation has a great effect on the physicochemical properties of XLPE cable insulation. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48575.     

High gain observer for a class of nonlinear systems with coupled structure and sampled output measurements: application to a quadrotor

This paper proposes a new high gain observer for a class of non-uniformly observable nonlinear systems with coupled structure driven by sampled outputs. The considered class of systems is particularly constituted by several subsystems where each subsystem is associated to a subset of the output variables. The observer design is carried out through two steps. First, a high-gain observer is proposed in the continuous-time output case under the assumption that an adequate persistent excitation condition is satisfied by each subsystem. Then, the proposed observer is redesigned to handle the case of sampled outputs leading thereby to a continuous-discrete time observer. The latter property is achieved thanks to the approach pursued along the convergence analysis. The effectiveness of the proposed observer is emphasised in a realistic simulation framework involving a mathematical model of a quadrotor which is diffeomorphic to the proposed class of considered systems.     

Thermal Aging Effects on Cu Ball Shear Strength and Cu/Al Intermetallic Growth

Intermetallic growth and ball shear behavior of annealed Cu wire bonds on Al have been studied. The shear strength of Cu ball bonds decreased with time, and ductile fracture was the dominant failure mode from 125°C to 150°C. Al pad peel-off occurred as the aging temperature was increased above 150°C. The overall Cu/Al intermetallic thickness exhibited parabolic behavior as a function of time. A linear correlation was established between ball shear strength, metal peel-off occurrence, and intermetallic growth. The Cu/Al intermetallic growth activation energy was 0.23 eV, and the intermetallics identified in the experiment were CuAl₂ and CuAl.     

Enhanced bactericidal effect of enterocin AS-48 in combination with high-intensity pulsed-electric field treatment against Salmonella enterica in apple juice

The effect of the broad spectrum cyclic antimicrobial peptide enterocin AS-48 combination with high-intensity pulsed-electric field (HIPEF) treatment (35 kV/cm, 150 Hz, 4 micros and bipolar mode) was tested on Salmonella enterica CECT 915 in apple juice. A response surface methodology was applied to study the bactericidal effects of the combined treatment. The process variables were AS-48 concentration, temperature, and HIPEF treatment time. While treatment with enterocin AS-48 alone up to 60 microg/ml had no effect on the viability of S. enterica in apple juice, an increased bactericidal activity was observed in combination with HIPEF treatments. Survival fraction was affected by treatment time, enterocin AS48 concentration and treatment temperature. The combination of 100 micros of HIPEF treatment, 30 microg/ml of AS-48, and temperature of 20 degrees C resulted in the lowest inactivation, with only a 1.2-log reduction. The maximum inactivation of 4.5-log cycles was achieved with HIPEF treatment for 1000 micros in combination with 60 microg/ml of AS-48 and a treatment temperature of 40 degrees C. Synergism between enterocin AS-48 and HIPEF treatment depended on the sequence order application, since it was observed only when HIPEF was applied in the presence of previously-added bacteriocin. The combined treatment could improve the safety of freshly-made apple juice against S. enterica transmission.     

Improvement of some pharmaceutical properties of drugs by cyclodextrin complexation. 4. Chlorpromazine hydrochloride

This study is a retrospective review of admissions, discharge records and blood culture results of neonates admitted to the Neonatal Intensive Care Unit of Korle Bu Teaching Hospital in Accra, from the first of January 1991 to the 31st of December 1992. During this two year period there were 443 positive blood cultures. Ninety percent of the blood cultures were from babies born in Korle Bu Teaching Hospital, thus making the incidence of neonatal bacteraemia 22.2 per 1000 live births. The overall mortality rate was 37.2%. Gram negative bacteria accounted for 70.9% and Gram positive bacteria for 29.1% of all neonatal bacteraemia. The most common isolates were Enterobacter species 29.6%; Streptococcus faecalis 14.4%; Staphylococcus aureus 10.8%; Acinetobacter species 9.5%; Klebsiella species 9% and Escherichia coli 8.8%. It is concluded that the incidence of neonatal bacterial sepsis is high in our hospital and is associated with a very high mortality rate. There is thus an urgent need to institute appropriate preventive and therapeutic measures.