FOSSES: Framework for open-source software evaluation and selection

A plethora of approaches exists for the evaluation and selection of open-source software (OSS) in the literature. However, these approaches are hardly ever used in practice for the following reasons: first, the lack of a situational-based procedure to define the evaluation criteria for OSS given its varied and dynamic nature; second, the inability of existing evaluation techniques, such as the analytic hierarchy process, to cope well with uncertainty factors, thus producing misleading results that affect the quality of decisions made; and third, a significant number of existing approaches require the prototyping of alternatives being considered in order to facilitate evaluation and decision-making. This study addresses the aforementioned challenges by evolving a process framework for evaluating and selecting OSS. The proposed framework is validated by applying it to a case study. In addition, expert opinion was elicited via questionnaires from 10 experts, and overall feedback suggests that 80% of them are willing to adopt the approach.     

Hydrogen production from CH4 dry reforming over bimetallic Ni–Co/Al2O3 catalyst

Bimetallic 5%Ni–10%Co/Al₂O₃ catalyst was synthesized using impregnation method and evaluated for methane dry reforming reaction at different reaction temperatures. NiO, Co₃O₄ and spinal metal aluminates, namely, CoAl₂O₄ and NiAl₂O₄ phases were formed on γ-Al₂O₃ support surface during calcination process. 5%Ni–10%Co/Al₂O₃ catalyst exhibited reasonable surface area of 86.93 m² g^?1 with small crystallite dimension of less than 10 nm suggesting that both Co₃O₄ and NiO phases were finely dispersed on the surface of support in agreement with results from scanning electron microscopy (SEM) measurement. Temperature-programmed calcination measurement indicates the complete thermal decomposition and oxidation of metal precursors, viz. Ni(NO₃)₂ and Co(NO₃)₂ to metal oxides and metal aluminates at below 700 K. Both CH₄ and CO₂ conversions were stable over a period of 4 h on-stream and attained an optimum at about 67% and 71%, respectively at 973 K whilst H₂ selectivity and yield were higher than 49%. The ratio of H₂/CO was always less than unity for all runs indicating the presence of reverse water–gas shift reaction. The activation energy for CH₄ and CO₂ consumption was computed as 55.60 and 40.25 kJ mol^?1, correspondingly. SEM micrograph of spent catalyst detected the formation of whisker-like carbon on catalyst surface whilst D and G bands characteristic for the appearance of amorphous and graphitic carbons in this order were observed on surface of used catalyst by Raman spectroscopy analysis. Additionally, the percentage of filamentous carbon was greater than that of graphitic carbon.     

Syngas production from methane dry reforming over Ni/SBA-15 catalyst: Effect of operating parameters

The influence of operating conditions including reactant partial pressure and reaction temperature on the catalytic performance of 10%Ni/SBA-15 catalyst for methane dry reforming (MDR) reaction has been investigated in this study. MDR reaction was carried out under atmospheric pressure at varying CH₄/CO₂ volume ratios of 3:1 to 1:3 and 923–1023 K in a tubular fixed-bed reactor. SBA-15 supported Ni catalyst exhibited high specific surface area of 444.96 m² g^?1 and NiO phase with average crystallite size of 27 nm was detected on catalyst surface by X-ray diffraction and Raman measurements. H₂ temperature-programmed reaction shows that NiO particles were reduced to metallic Ni⁰ phase with degree of reduction of about 90.1% and the reduction temperature depended on the extent of metal-support interaction and confinement effect of mesoporous silica support. Catalytic activity appeared to be stable for 4 h on-stream at 973–1023 K whilst a slight drop in activity was observed at 923 K probably due to deposited carbon formed by thermodynamically favored CH₄ decomposition reaction. Both CH₄ and CO₂ conversions increased with rising reaction temperature and reaching about 91% and 94%, respectively at 1023 K with CO₂ and CH₄ partial pressure of 20 kPa. CH₄ conversion improved with increasing CO₂ partial pressure, ${\mathit{P}}_{\mathit{C}{\mathit{O}}_{\mathit{2}}}$ and exhibited an optimum at ${\mathit{P}}_{\mathit{C}{\mathit{O}}_{\mathit{2}}}$ of 30–50 kPa depending on reaction temperature whilst a substantial decline in CO₂ conversion was observed with growing ${\mathit{P}}_{\mathit{C}{\mathit{O}}_{\mathit{2}}}$. Additionally, CH₄ and CO₂ conversions decreased significantly with rising CH₄ partial pressure because of increasing carbon formation rate via CH₄ cracking in CH₄-rich feed. Post-reaction characterization shows that active Ni metal phase was not re-oxidized to inactive metal oxide during MDR reaction. The heterogeneous nature of deposited carbons including carbon nanofilament and graphite was detected on catalyst surface by Raman measurement.     

Antimicrobial activity of some medicinal plants extracts on Escherichia coli, Salmonella paratyphi and Shigella dysenteriae

AIM: To study the toxic effects of norfloxacin (Nor) on EEG and ultrastructure of the brain. METHODS: EEG was recorded in the sensorimotor area of rat cortex after Nor 150 and 300 micrograms.kg-1 were injected into the right ventricle of the brain. RESULTS: Spike waves occurred, first at the ipsilateral side and then bilaterally. The seizure spike appeared at 168 +/- 129, 51 +/- 35 s, and 276 +/- 138, 118 +/- 65 s in the right and left cerebral cortices in 150 and 300 micrograms.kg-1 groups, respectively. The wave forms were variable, the wave amplitude and frequency increased gradually, accompanied with limb twitching. Neuron degeneration was seen in both cerebral hemispheres, hippocampus, and cerebellum 120 min after the i.c.v. of Nor 300 micrograms.kg-1: myeloid degeneration of Golgi complex, rough endoplasmic reticulum, and neuropils; swelling of cytoplasm; dissolution of nuclears and chromatin; necrosis of gliocytes and the appearance of changes in both the light and dark neurons, especially the dark ones. CONCLUSION: Rat brain was widely damaged after the kindling by Nor.     

Rheological characteristics of South African commercial sauces

In this work, the rheological characteristics of three commercial culinary sauces obtained from a shop in South Africa were studied using both oscillatory and rotating rheometry. The materials were found to be non‐Newtonian and shear thinning in the temperature range of 10 °C and 60 °C and a shear rate of 0.1–800 s^?1. Their flow behaviour characteristics were adequately described by both the power law and Herschel–Bulkley rheological models. Their activation energy of flow ranged from 11.94 to 18.34 kJ mol^?1. The materials were observed to be weak gels with linear viscoelastic of about 1%. Increasing frequency did not significantly affect the viscoelastic properties of all the three substances. The materials were found to suffer permanent structural deformation (in terms of viscosity) when heated and subsequently cooled between 10 °C and 70 °C.     

Effect of Deposition Temperature on Some Properties of MOCVD Molybdenum Sulphide Thin Films

Molybdenum sulphide thin films were deposited on sodalime glass, silicon Wafer and stainless steel （AISI 304L） substrates using Metal Organic Chemical Vapour Deposition （MOCVD） technique at temperatures ranging from 360 ℃ to 450 ℃. The films were characterized using Rutherford Backscattering Spectroscopy （RBS）, Ultraviolet-Visible Spectroscopy, Four point probe technique, Scanning Electron Microscopy （SEM） and Atomic Force Microscopy （AFM）. Elemental analysis showed that the S/Mo ratio increases from 1.22 to 2.33 with increasing temperature. The optical band gap varies from 1.69 eV to 1.79 eV as deposition temperature increases. The electrical conductivity ranging from 0.5 Ω-1 cm-1 to 1.30 Ω-1 also depends on deposition temperature. SEM micrographs of the films showed the layered structure of the film with an estimated grain size that increases from 1.6 μm to 2.4 μm as the deposition temperature increases. This study demonstrates that the properties of the films depend on the deposition temperature.