Open Access Original Research Article

Prediction of Generalised and Localised Carbon Steel Corrosion Using Improved Norsok and Papavinasam Models

Olugbenga Adebanjo Falode, Akintola Sarah, Akinlade Imam Akintomiwa

Chemical Science International Journal, Page 1-10
DOI: 10.9734/SJI/2017/37752

In this study, Norsok and Papavinasam models have been improved so as to reduce the model limitations. The Norsok model was improved by accounting for 3 phase flow in calculating the wall shear stress and correcting for oil wetting and formation of protective layers in steel pipes during hydrocarbon transportation while the Papavinasam model was improved by using the Weibull distribution to account for time effect in corrosion predictions. The corrosion rates predicted fairly agreed with the field values. The improved models are user friendly and readily available and thus applicable for corrosion studies in the oil and gas industry.

Open Access Original Research Article

Preparation, Solubilization and In vitro Anti-tumour Effect of Water-soluble Betulinic Acid/Oligo(polylvinylamino) Bridged bis(β-cyclodextrin)s Complexes

Yiou Tao, Yang Han, Shihui Dong, Xiaocheng Fan, Ting Wang, Xiufeng Yan

Chemical Science International Journal, Page 1-15
DOI: 10.9734/CSJI/2017/39109

A series of water-soluble betulinic acid complexes of betulinic acid/oligo(diethylenetriamino) bridged bis(β-cyclodextrin) (BA/DT-β-CD), betulinic acid/oligo(triethylenetetramino) bridged bis(β-cyclodextrin) (BA/TT-β-CD) and betulinic acid/oligo(tetraethylenepentamino) bridged bis(β-cyclodextrin) (BA/TP-β-CD) were prepared and characterized. IR, SEM, MS and 1H NMR were used to characterise these complexes. The results show that the two cyclodextrin cavities and tether groups of the aforementioned bis(β-cyclodextrin)s can form a well-organized pseudo cavity to accommodate the branch group of BA, respectively. By UPLC analysis, the water solubility was remarkably increased to approximately 310.97, 144.94 and 75.04 μg mL-1 by the solubilising effects of DT-β-CD, TT-β-CD and TP-β-CD, respectively. Furthermore, the anti-tumour effect against HeLa cell line was tested by MTT assay, and the IC50 values of BA in BA/DT-β-CD complex water solutions are 103.89 ± 5.12 μmol L-1, which possess an obvious antiproliferative activity against HeLa cell line.

Open Access Original Research Article

Preparation and Characterization of Poly(L-lactic acid)/Chitosan/Microcrystalline Cellulose Blends

Md. Sagor Hosen, Md. Hafezur Rahaman, M. A. Gafur, Rasel Habib, M. R. Qadir

Chemical Science International Journal, Page 1-10
DOI: 10.9734/CSJI/2017/39534

To prepare biodegradable and biocompatible polymer composites with better thermal and mechanical properties, five different Poly(L-lactic acid)(PLLA)/Chitosan/ Microcrystalline Cellulose (MCC) blends, with a different ratio, were prepared and characterized. MCC was extracted from jute fiber by conventional acid hydrolysis method with 64 wt% H2SO4 and chitosan was extracted from shrimp shell by successively carrying out demineralization, decolorization, deproteinization and deacetylation steps. PLLA was blended with a constant percentage (20 percent) of chitosan and a calculated amount of MCC by solution casting method using a suitable solvent for each. Prepared samples were characterized by Fourier-Transform Infrared Spectroscopy (FTIR) for the identification of their compatibility in blends, Wide-Angle X-ray Diffraction (WAXD) for crystalline species and crystallinity analysis, Thermo-Gravimetric Analysis (TGA) and Differential Thermal Analysis (DTA) for thermal properties measurement. Results from FTIR analysis showed that except hydrogen bonding, there are no new characteristic absorption peaks observed in the spectrum of blends and confirm that PLLA, Chitosan, and MCC have better compatibility in blends via intermolecular hydrogen bonding. WAXD profiles data show the variation in crystallinity of different blends. TGA and DTG results indicate that MCC can improve the heat resistivity of the PLLA/Chitosan/MCC blends by the addition up to 5%.

Open Access Original Research Article

Chemical Fractionation of Heavy Metals in the Soil of Auto-Mechanic Workshops in Akure, Ondo State, Nigeria

Ajisafe Monday Peter, O. O. Ajayi, E. O. Abata, Akinnawo Solomon, M. T. Oluwalope

Chemical Science International Journal, Page 1-16
DOI: 10.9734/CSJI/2017/38088

Total metal concentrations and sequential extraction scheme were employed to investigate the potential environmental risk of seven important metals in the soil of selected auto-mechanic workshops in Akure metropolis, Ondo State, Nigeria. Soil physicochemical parameters were also determined with the following results: pH ranged from 5.50-6.32, total organic carbon from 0.96-1.56%, particle size indicates the soil to be mainly sandy, Cation Exchange Capacity (CEC) ranged from 7.00-9.00 Cmol/Kg. The concentrations (mg/kg) for the seven metals in Ilesha-Garage soil samples were 4.25±1.06 (Cd), 17.00±0.00 (Cr), 20.75±0.35 (Cu), 4750.00±0.00 (Fe), 4.00±0.70 (Ni), 40.50±0.70 (Pb), 40.75±0.35 (Zn) while the mean concentrations of metals (mg/kg) in Oyemekun soil samples were 7.50±0.00 (Cd), 22.00±0.70 (Cr), 33.25±0.35 (Cu), 6475.00±0.35 (Fe), 5.00±0.01 (Ni), 60.00±0.00 (Pb) and 48.50±0.70 (Zn) respectively. Cadmium content in the soil samples exceeded the target values of the Department for Petroleum Resources (DPR) regulatory Standards for soil. Sequential extraction by fractionation reveals that the average percentage concentration of  Cd, Cr, Ni, Pb and Fe were more prevalent in residual fractions, while Zn and Cu were found more in Iron-Manganese Oxides, carbonate in addition to residual fractions. The heavy metals speciation of the soil samples indicates that the heavy metals were predominately found in both the residual and non-residual fractions suggestive of control by geogenic and anthropogenic sources respectively. Eco-toxicological assessment of the soil samples using the mobility factor indices revealed the following sequence: Lead (31.11%) > zinc (21.11%) > Nickel (20.75%) > Copper (12.24%) > Chromium (10.73%) > Cadmium (0.80%) > Iron (0.09%). The pollution index assessment indicates that most of the metals fall within the “slight contamination” and “moderate contamination” range in the soil.

Open Access Original Research Article

Quality Characters and Shelf Life of Banana (Musa spp.) cv. Barjahaji as Influenced by Bunch Feeding of Nitrogen (N) and Potassium (K)

Thanuram Teron Millik, Kartik Baruah, Vikash Kumar, Nishant Barik

Chemical Science International Journal, Page 1-7
DOI: 10.9734/CSJI/2017/38999

The present investigation was carried out at the Experimental Farm, Department of Horticulture, Assam Agricultural University, Jorhat during March 2015 to June 2016 to study the impact of denavelling (removal of male bud) and stalk-end nutrient application (bunch feeding) on the improvement of bunch quality of banana cultivar cv. Barjahaji. The experiment was conducted with nine (09) treatments and three (03) replication in a randomized block design (RBD). Nitrogen and Potassium were applied (at stalk-end after removal of male bud) in the form of different chemicals along with cow dung and compared with control. Among the treatments less acidity (0.23%), the highest total soluble solids (29.23 ºBrix), total sugars (17.42%), reducing sugar (9.09%), non-reducing sugar (8.33%) and Sugar acid ratio (75.74 %) were observed in the treatment T7 (500 g fresh cow dung + 7.5 g Urea + 7.5g  K2SO4). In respect to shelf life, bunch feeding with 500 g fresh cow dung + 7.5 g Urea + 7.5g K2SO(T7) had attained the highest shelf life (7.67 days). It is evident from the study that there is a positive effect of bunch feeding on quality attributes and shelf life of banana. Hence bunch feeding of 500 g fresh cow dung + 7.5 g Urea + 7.5 g K2SO4 can be recommended for banana cv. Barjahaji (AAA) for getting best quality fruits of higher shelf life.