Digital Forensic Readiness in Megacities

As megacities emerge in splendor, so also do threats to security and sustainability of these cities. Earlier research found out that the leading threat amongst several security and safety threats in megacities are organized crimes. Since technology is involved in all facets of megacities, including the threats therein, this paper seeks to stimulate scientific curiosity in finding out effective and sustainable ways of harnessing technology in readiness, to protect these cities from threats rather than reactively responding to them. Using Lagos State, an emerging mega city as a case study, we seek how to systematically execute this concern which should be built from the scratch into megacities systems.A Megacity Digital Forensic Readiness Model (MEDFORM) is proposed in this paper

Effect of moisture sorption hysteresis on thermodynamic properties of two millet varieties

Application of reversible thermodynamic principles to gain fundamental understanding of food–water interactions in foods has met with limited success due to the presence of moisture sorption hysteresis which is a manifestation of irreversibility. This study was aimed at understanding the nature and extent of influence of hysteresis on thermodynamic properties of two millet varieties namely EX-BORNO and SOSAT C88. Moisture sorption data (adsorption and desorption) in the water activity and temperature ranges of 0.07 – 0.98 and 30°C – 70°C, respectively were used. Ratio of latent heat of moisture sorption to the latent heat of pure water was determined using Clausius-Clapeyron equation. Effect of moisture content on ratio of latent heat of sorption to latent heat of pure water was determined using Gallaher model. Net integral enthalpy was determined at constant spreading pressure with monolayer moisture contents calculated using Brunauer-Emmett-Teller (BET) and Guggenheim-Anderson-de Boer (GAB) models. Spreading pressure was determined using an analytical procedure. Gibbs equation was used to evaluate net integral entropy. Net isosteric heat of sorption and differential entropy were evaluated and used to investigate the enthalpy‐entropy compensation theory. Latent heat of moisture sorption in the two millet varieties decreased with increase in moisture content and approached latent heat of pure water at a ‘free water’ point of between 32% and 42% moisture content (d.b.) in adsorption and desorption, respectively. Desorption latent heat of moisture was higher than the adsorption values and the difference decreased with increase in moisture content. Monolayer moisture content decreased with increase in temperature, with the GAB being higher than the BET values. Desorption monolayer moisture was higher than that of adsorption. Spreading pressure increased with increase in water activity, with adsorption isotherm being higher than that of desorption and temperature having no significant effect. Net integral enthalpy decreased with increase in moisture content with effect of hysteresis being more marked in EX-BORNO than in SOSAT C88. Net integral entropy decreased with increase in moisture content to minimum values and thereafter, maintained sinusoidal trend with adsorption curve lagging behind desorption and varnishing at 18% and 16% (db) moisture content in EX-BORNO and SOSAT C88 respectively. Net isosteric heat of sorption and differential entropy decreased with increase in moisture content with effect of hysteresis being more pronounced in EX-BORNO. Moisture sorption process in the grains was found to be enthalpy driven with differential enthalpy varying linearly with differential entropy. Inequality in isokinetic and harmonic mean temperatures confirmed the enthalpy‐entropy compensation theory. Hysteresis was found to have effect on the isokinetic temperature, causing the values of desorption isokinetic temperature to be higher than the adsorption values

Mechanism and Isotherm Modeling of Effective Adsorption of Malachite Green as Endocrine Disruptive Dye using Acid Functionalized Maize Cob (AFMC)

Cationic Malachite green has been identified as a candidate of endocrine disruptive compound found in the environment. In this study, the mechanism and isotherm modeling of effective adsorption of cationic malachite green dye onto acid functionalized maize cob (AFMC) was investigated by batch technique. The operational parameters such as initial concentration (100 – 600 mg/L); contact time (10 – 120 mins) and pH (3 – 10) influenced the removal efficiency and quantity adsorbed. Maximum of 99.3% removal efficiency was obtained at optimum conditions. AFMC physicochemical properties (surface area 1329 m2 /g and particle size 300μm0.97 and consistently low values of SSE, X2, HYBRID and MSPD adsorption statistical error functions (ASEF), equilibrium data were best fitted to Freundlich isotherm. Kinetic data were best described by pseudo second-order model with consistent R2 >0.98 and validated by ASEF. The mechanism of process was better described by intraparticle diffusion. Evidence of adsorption process was confirmed by change in morphology and surface chemistry determined by SEM and FTIR respectively. The performance of AFMC enlisted it as a sustainable and promising low-cost adsorbent from agro-residue for treatment of endocrine disruptive dye polluted water

Anaerobic conversion of Chromolaena odorata (Siam weed) to biogas

This study evaluated the anaerobic mono-digestion of two different samples of Chromolaena odorata. Combinations of mechanical and thermo-alkaline pretreatments were applied to one of the two samples and labeled as ‘‘X’’ while the second had no thermo-alkaline treatment and was labeled as ‘‘Y’’. The Central Composite Design was used to design the pre treatments. The physicochemical characteristics of the substrates were carried out using standard methods after appropriate pretreatments. From the experimental set-ups, the most probable actual biogas yields in experiments ‘‘X’’ and ’’Y’’ were 0.3554 m3/kg Total Solid (TS)fed and 0.1803 m3/kg TSfed with the desirability of 99 and 100%, respectively. Further shown in the result is a 49.2% higher experimental (actual) biogas yield in experiment ‘‘X’’ over ‘‘Y’’. Gas chromatographic analysis revealed the CH4 and CO2 content of both experiments to be 65±1.5%; 21±3% and 53.5±2.5%; 26±3%, respectively. Combination of different pretreatment methods enhanced enormous biogas yield from the digested substrates. Optimization of the generated biogas data was carried out using the Response Surface Methodology (RSM) and the Artificial Neural Networks (ANNs). The coefficient of determination (R2) for RSM was lower compared to that of ANN. This shows that ANN

Biochemical conversion of fruit rind of Telfairia occidentalis (fluted pumpkin) and poultry manure

Environmental pollution by solid wastes and inadequate energy supply are some of the major challenges facing the developing world. This study evaluated the potentials of Fluted pumpkin fruit rind and poultry manure for biogas generation. Mechanical and thermo-alkaline pre-treatments were applied to two samples labeled ‘O’ and ‘P’ while the third sample (Q) had no thermo-alkaline treatment. The physicochemical characteristics of the substrates revealed richness in nutrients and mineral elements. The results showed that use of a combination of pre-treatment methods enhanced the biogas yield in the pre-treated substrates. Analysis of the gas composition showed 66.5 ± 2.5% Methane, 25 ± 1% Carbon dioxide; 58.5 ± 2.5% Methane, 26 ± 1% Carbon dioxide; 54.5 ± 1.5% Methane, 28 ± 2% Carbon dioxide for the three experiments, respectively. All the obtained values show the models had a high predictive ability. The substrates should be further used for energy generatio

Recent advances on graphyne and its family members as membrane materials for water purification and desalination

Graphyne and its family members (GFMs) are allotropes of carbon (a class of 2D materials) having unique properties in form of structures, pores and atom hybridizations. Owing to their unique properties, GFMs have been widely utilized in various practical and theoretical applications. In the past decade, GFMs have received considerable attention in the area of water purification and desalination, especially in theoretical and computational aspects. More recently, GFMs have shown greater prospects in achieving optimal separation performance than the experimentally derived commercial polyamide membranes. In this review, recent theoretical and computational advances made in the GFMs research as it relates to water purification and desalination are summarized. Brief details on the properties of GFMs and the commonly used computational methods were described. More specifically, we systematically reviewed the various computational approaches employed with emphasis on the predicted permeability and selectivity of the GFM membranes. Finally, the current challenges limiting their large-scale practical applications coupled with the possible research directions for overcoming the challenges are proposed

Effect of polishing duration on physical, milling, cooking, and sensory properties of a novel mix‐colored Nigerian parboiled rice

Background and objectives Polishing is a step of milling process to produce white rice. It influences rice quality. This study evaluates the effect of increased polishing duration (0, 1, 2, and 3 min) on the physical, milling, cooking, and sensory properties of novel mix‐coloured Nigerian rice. These quality parameters influence the consumers’ choice. Findings Polishing duration had a significant effect on the physical, milling, cooking, and sensory properties of the milled rice. As the polishing duration increased, the length, width, length/width ratio, 1000‐grain weight, bulk density, true density, porosity, optimum cooking time, cooking loss, aroma, and flavour of the milled rice reduced while increased polishing duration increased the head rice yield, percentage broken rice, milled rice yield, percentage dockage, kernel elongation ratio, width expansion ratio, water uptake ratio, texture, appearance, and overall acceptability of the milled rice. The correlations between physical, milling, cooking and sensory properties were strongly significant (P˂0.01 and P˂0.05). Conclusions This study revealed that increasing the polishing duration improves the cooking, head rice yield, milled rice yield and some sensory quality attributes of the mix‐coloured parboiled rice, but reduced its physical attributes. Significance and novelty The mix‐coloured rice showed an improved milling, cooking, and sensory attributes but poor physical characteristics during polishing which is very vital to Rice milling industry

Neural network and adaptive neuro-fuzzy inference system modeling of the hot air-drying process of orange-fleshed sweet potato

The primary objective of this study is to determine the hot air drying characteristics and nutritional quality of orange-fleshed sweet potato (OFSP) in a convective dryer. Three temperatures (323.15, 333.15, and 343.15 K) and fan speed levels (0.5, 0.9, and 1.3 m/s) were used. A rehydration study of dried OFSP was also carried out. Modeling and prediction of experimental moisture data were done using artificial neural networks (ANNs) and adaptive neuro-fuzzy inference system (ANFIS) models. The result showed that the drying rate and rehydration ratio were significantly (p < .05) affected by drying temperature and fan speed levels. The effective diffusivity (Deff) of the samples ranged from 2.5 × 10–9 to 4.25 × 10–9 m2/s, and it was found to increase with temperature and fan speed. Protein and fat content appeared to be strongly influenced by drying processing variables, whereas other properties appeared to be insignificant. ANFIS showed better modeling ability than ANNs in predicting the experimental moisture data of OFSP with R2 and RMSE values of .99786 and 0.0225 respectively. In conclusion, the findings from this research will be useful in product optimization and process monitoring of hot air drying of OFSP, in establishing its drying temperature and fan speed