Adsorption of Methyl Orange Dye from Aqueous Solution by Carbonized Iron Tree (Prosopis africana) Seeds: Kinetic, Equilibrium and Thermodynamic Studies

Adsorption of Methyl orange dye from aqueous solutions by carbonized Prosopis africana (CPA) seeds was investigated using a batch system under controlled conditions. The carbonized Prosopis africana (CPA) seed was characterized by Fourier transform infrared spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) methods. The point of zero charge (PZC) of carbonized Prosopis africana (CPA) was to be 6.10. The kinetic data was best relatively described by pseudo-second order in relation to all the models studied. Adsorption parameters such as effect of pH, contact time, adsorbent dosage and initial concentration were studied for optimization purposes. The adsorption isotherm for the processes was also estimated and established to fit well the Freundlich isotherm model relative to other models tested. Thermodynamic studies revealed that the adsorption processes were exothermic and feasible in nature. This indicates that carbonized Prosopis africana (CPA) seed can be employed as a good adsorbent for the treatment of wastewater containing dyes such as Methyl orange

COMPUTATIONAL STUDY OF THE CHEMICAL REACTIVITY PROPERTIES OF GLYCOSYDATED SECO-IRIDOID COMPOUND AS CORROSION INHIBITOR, ON MILD STEEL AND ALUMINUM METAL

In this research, the compound was studied theoretically using computational methods to give further analysis on the inhibition of oleuropein on mild steel and Aluminium. Parameters were studied using quantum chemical method through DFT and molecular dynamic simulations. Mild steel Fe (111) and Al (110) surfaces was used due to their respective close packed and densely atom. Fukui function, the local and global reactivity were calculated to give the reactivity of the molecule. Based on the values of calculated adsorption and binding energies (-70.287, 70.287 Kcal/mol) and (-113.193, 113.193 Kcal/mol) obtained on both surfaces, the mechanism of oleuropein is inferred to exhibit physiosorption on Aluminium surface and Chemisorption on mild steel surface

Artificial Intelligence Approaches in Student Modeling: Half Decade Review (2010-2015)

Intelligent Tutoring Systems (ITSs) are special classes of E-learning systems designed using Artificial Intelligence (AI) approaches to provide adaptive and personalized tutoring based on the individuality of students. The student model is an important component of an ITS that provides the base for this personalization. During the course of interaction between student and the ITS, the system observe student’s actions and other behavioral properties, create a quantitative representation of these student’s attributes called a student model

Kinetic and Isotherm Studies of Methyl Violet Adsorption onto Carbonized Waterlily (Nymphaea lotus) Leaves Powder

In this study, the adsorption of methyl violet from an aqueous solution using carbonised water lily (CWL) leaves powder as a low-cost, efficient and eco-friendly adsorbent was investigated using a batch system under controlled conditions. The adsorbent's moisture, organic matter, ash, bulk density, pore volume, and pH were determined. The adsorbents were characterised by scanning electron microscopy (SEM) and Fourier Transform Infrared (FT-IR) techniques which confirm the adsorption of the methyl violet onto the CWL adsorbents. The effect of adsorption parameters such as contact time, dosage, initial concentration, pH and temperature were studied for optimisation. It was confirmed that contact time, dosage, concentration, pH and temperature positively affected the adsorption process. The kinetic data were best described by pseudo-second order under all experimental temperatures. The adsorption isotherms were estimated and established to fit nicely into the D-R model compared to other models generated and tested. Thermodynamic studies of the sorption process indicate that the process was feasible, spontaneous, and exothermic and decrease in the randomness of the adsorption process during the transfer of molecules between the adsorbent and adsorbates with entropy (∆S) of 23.77 J/mol.K. due to negative values of Gibb’s free energy observed. This study confirmed that CWL could be employed as a low-cost, eco-friendly adsorbent for removing toxic dyes such as methyl violet from an aqueous solution

Properties of Foodborne Pathogens and Their Diseases

Thousands of foodborne pathogens are causing a great number of diseases with significant effects on human health and economy. Foodborne pathogens can contaminate food items not only during production and processing, but also at the time of storage and transport before consuming. During their growth, these microorganisms are capable of secreting different type of toxins into the extracellular environment. Likewise, other harmful substances can be also released and can contaminate food after breakup of food pathogens. Many microbial toxins can withstand inactivation, and can endure harsh treatment during food processing. Many of these molecules are partaken in cellular processes and can display different mechanisms of pathogenesis of foodborne organisms. Thus studying the properties of foodborne pathogens can help in the understanding of their contamination and inactivation. In the present review, we discussed extensively on the properties of foodborne pathogens including bacteria, viruses and parasites. In addition, some of the diseases caused by foodborne pathogens and the mechanism of their pathogenesis were also discussed

DFT and molecular dynamic simulation study on the corrosion inhibition of Aluminum by some flavonoids of Guiera Senegalensis leaves

Quantum chemical calculations and molecular dynamics simulations were performed to investigate the effect of four flavonoids compounds (Kaempferol, Quercetin, Myricetin and Rhamnetin) from Guiera Senegalensis leaves on corrosion inhibition of aluminium metal in vapour phase. Quantum chemical parameters including EHOMO, ELUMO, energy gap (ΔE), electronegativity (χ), global hardness (η), global softness (σ) and fraction of electrons transferred (ΔN) from the flavonoid molecule to the aluminium surface were calculated and the results indicate that the larger the molecular size the better the inhibition efficiency. Local reactive sites through Fukui indices were also calculated to explain the effect of electronic and structural features of the flavonoid compounds present in the leaves extract of Guiera senegalensis (GS). The results showed that the point of interaction of inhibitor molecule with the Al(1 1 0) surface were through hydroxyl and carbonyl functional groups of the studied compounds. Molecular dynamic simulations revealed that the adsorption behaviour of each flavonoid molecule on Al(1 1 0) surface through quench dynamics were found to obey the mechanism of physical adsorption and the more negative is the adsorption energy between the inhibitor-metal surface the better inhibition performance of the molecule on Al(1 1 0) surface. &nbsp

Paraquat dichloride adsorption from aqueous solution using Carbonized Bambara Groundnut (Vigna subterranean) Shells

Carbonized Bambara GroundNut Shell (CBGNS) was used as adsorbent for the adsorption of paraquat dichloride (PQ) from aqueous solution. The prepared adsorbent was characterized using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy methods. Several parameters that might affect the adsorption process including pH, contact time, adsorbent dosage, temperature and initial concentration were investigated and optimized using batch adsorption technique. Results of the study revealed that maximum removal efficiency (98%) was achieved using 0.05g adsorbent dosage, solution pH of 5 and 60 min of contact time. The equilibrium experimental result revealed that Langmuir model best described the adsorption process with R2 value of 0.956.The heat of adsorption process was estimated from Temkin Isotherm model to be 19.99J/mol and the mean free energy was estimated from Duninin-Radushkevich (DRK) isotherm model to be 0.289KJ/mol indicating chemisorptions process. The kinetic and thermodynamic studies revealed that the adsorption processes followed pseudo-second-order kinetics with R2 value of 0.999 and the value of ∆G (- 27.74 kJ mol-1), ∆H (13.145 kJ mol-1) indicate the spontaneous and endothermic nature of PQ adsorption on CBGNS. The results suggested that CBGNS had the potential to become a promising material for PQ contaminated water treatment. Keywords: Adsorption, Paraquat dichloride, Carbonized Bambara Ground nut shell, Water treatment