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Open access

Vandana Singh and Manager Rajdeo Singh

Abstract

This investigation deals with the chemical composition and microstructural analysis of the iron object, a spear excavated from Sanur, Tamil Nadu- a megalithic site dated 300 B.C. to 50 A.D. Phase analysis and microstructural examination were carried using XRD, optical and variable pressure scanning electron microscope (VP-SEM). Optical micrograph shows the equiaxed grain structure along with the Newman bands. Formation of Newman bands suggests that the original artifact was forged at high temperature followed by cooling, although not so rapid to produce the marked hardening. The absence of carbides at the grain boundary, within the grains and lower value of micro-hardness indicates that the iron spear was not subjected to the carburizing treatment. Results of corrosion characterization revealed that deterioration of excavated iron artifact is associated with the presence of chlorine in corrosion products. However, compact nature of the outer rust (goethite) was helpful in protecting the object. The formation of goethite [∝-FeOOH] layer may prevent the iron matrix suffering from attacks by other environmental factors due to its good continuity. In addition, less aerated environment of storage and no history of any cleaning of object were also helpful in preventing the iron spear from further deterioration.

Open access

Leizou Kaywood Elijah and Muhammad Aqeel Ashraf

Abstract

This study was carried out to investigate the distribution and contents of sixteen priority polycyclic aromatic hydrocarbons (PAHs) in water from Amassoma axis of the Nun River, Bayelsa State, Nigeria. The PAH contaminations in the river water samples was performed using GC-MS method. The results were similar for all of the three sampling stations. Six LMW PAHs: naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene and five HMW PAHs: fluoranthene, pyrene benzo (a)anthracene, chrysene and benzo(a)pyrene were found. The ΣPAH concentration ranged from 0.111mg/L to 0.26mg/L. In this study, PAH fingerprint ratios for determining both petrogenic and pyrogenic (pyrolytic) PAH accumulation in the environment and Toxic equivalency factor (TEF) used to estimate relative toxicity of a PAH compared to that of BaP was employed. The Ph/An ratio for water samples were 0.00, 0.33 and 0.00 in three stations, while associated figures for Fl/Py ratio values were 0.67, 0.83 and 0.50 respectively. Pearson correlation matrice analysis reveals a positive correlation between the PAHs; this could indicate a common source for some of the PAHs, however, some were negatively correlated with each other. This behavior could indicate non-point source. A comparative analysis of PAHs concentrations in the water samples with WHO standards revealed that the results obtained in this study were within the permissible levels, however, carcinogen PAHs present in the water of the Amassoma axis, Nun River may pose a threats to human health.

Open access

Ameet Kumar, Aamna Balouch, Ashfaque Ahmed Pathan, Abdullah, Muhammad Saqaf Jagirani, Ali Muhammad Mahar, Muneeba Zubair and Benazir Laghari

Abstract

The remediation of organic and inorganic pollutants from the aqueous environment has touched a certain level with the development of research. Environmental pollution is increasing day by day due to industrial activities which cause a negative effect on human health and the ecosystem. Nowadays, heavy metals have a special concern due to its toxicity, persistence and bioaccumulation in nature. Toxic metals like chromium, nickel, arsenic, lead, mercury, cadmium are the main contaminants of water because they are non-biodegradable in nature. Nickel is also a toxic metal, mostly used in industries because of its anticorrosion behaviour. As a consequence nickel is present in the wastage of electroplating, tableware, metal finishing, plastics manufacturing, nickel-cadmium batteries, fertilizers and mining industries and these waste have dangerous impact on the human health and environment and causes the diseases i.e. diarrhea, anemia, hepatitis, kidney damage, gastrointestinal distress, skin dermatitis, and central nervous system dysfunction. In the present review article, several techniques are discussed for the treatment of nickel from the industrial environment. The elimination of nickel from wastewater is not important only for economic purposes but also for environmental safety.

Open access

Veerasamy Ravichandran and Rajak Harish

Abstract

The main objective of the present study was to establish significant and validated QSAR models for imidazoles and sulfonamides to explore the relationship between their physicochemical properties and antidiabetic activity. Two dimensional QSAR models had been developed by multiple linear regression and partial least square analysis methods, and then validated for internal and external predictions. The established 2D QSAR models were statistically significant and highly predictive. The validation methods provided significant statistical parameters with q2 > 0.5 and pred_r2 > 0.6, which proved the predictive power of the models. The developed 2D QSAR models revealed the significance of SlogP and T_N_O_5, and Mol.Wt and SsBrE-index properties of imidazoles and sulfonamides on their antidiabetic activity, respectively. These results should prove to be an essential guide for the further design and development of new imidazoles and sulfonamides having better antidiabetic activity.

Open access

Traian Tache, Răzvan Chirică, Marius-Daniel Radu, Gabriela Gegiu and Sorin Rugină

Abstract

Enterotoxins produced by Clostridium difficile cause a series of biochemical and immunological manifestations in the cascade leading to alteration of the enterocitus cytoskeleton, intestinal inflammation and diarrhea that can greatly impair the patient’s biological status. The genome of the Clostridium difficile bacterium shows a series of evolutionary adaptations that can give it a high degree of resistance or adaptability to many known pharmacological classes. Changing the diversity of intestinal microbiota induced by the use of antibiotics creates a favorable environment from all points of view for Clostridium difficile spore activity. The theme addresses in an original way but related to the epidemiological studies presented in the literature a correlative aspect between the pathological group and the infection with Clostridium difficile. From the data presented, there is a direct correlation between Clostridium difficile infection and the use of antibiotic therapy as a curative or preventive treatment. Gastrointestinal and neurological pathologies, due to the use of curative but also preventive antibiotic therapy, are at increased risk for the installation of Clostridium difficile infection. The study presented may be a first step in raising awareness of the rational use of antibiotics and avoiding non-assisted community antibiotic therapy.

Open access

Habibat F. Chahul, David T. Orhemba and Taiwo A. Gbadamosi

Abstract

The inhibition of mild steel corrosion in 1.0 M HCl and 0.5 M H2SO4 by Cissus populnea stem extract was investigated using weight loss measurements in the temperature range of 303 – 333 K. Results from the study revealed that Cissus populnea stem extract inhibited the corrosion of mild steel in both acid media. Inhibition efficiency of the stem extract increased with increase in the extract concentration but decreased with immersion time. The kinetics of the reaction aligned with a first order type. Thermodynamics investigations showed that Cissus populnea extract is adsorbed on the steel surface through physical interactions, and the adsorption process was endothermic and spontaneous. Langmuir, Freundlich and Temkin isotherm models best described the adsorption mechanism of the stem extract on the steel surface.

Open access

Serap Ayaz Seyhan, Cağlar Demirbağ and Emre Dölen

Abstract

Dyer’s kermes (Kermes vermilio) is found only on the kermes oak (Quercus coccifera L). They were used in the past for the preparation of dyes for textiles and as a pharmaceutical. The main constituents of this insect are kermesic acid (ka) and flavokermesic acid (fk). Historically and culturally important dyer’s kermes insect red dyes were investigated by high performance liquid chromatography. Kermes in the Northwest of Turkey were analyzed first time the relative amount of the dyestuffs although their presence has been reported analytical works related to this insect. The relative amount in the acid hydrolyzed extract of Kermes vermilio from the Northwest of Turkey looked very similar to the France.

Open access

Effiong Ukorebi Etim

Abstract

Application of dried plant water soluble extracts in soil Pb decontamination is rear, but advantageous due to their ecological biodegradability. Single batch laboratory scale suitability of Terminalia mantaly, Panicum maximum, Eleusine indica and water as washing solutions for Pb removal from contaminated and spiked soils at different soil pulp densities (3%, 6%, 9%, 12%, 15% and 18%) and washing time (1, 3, 6, 12, 24 and 96 h) was investigated. Washings of Terminalia mantaly and Panicum maximum proved more efficient comparatively for contaminated soil with Pb removal efficiency of 27.2±0.64% and 27.0±0.52% respectively at 3% soil pulp density and washing time of 96 h. Removal efficiency increased with increasing washing time but decreased with increasing of soil pulp density. Furthermore, water was found effective for removing Pb from spiked soils with maximum removal efficiency of 74.5±3.38% at 3% soil pulp density after 1 h washing. High exchangeable fraction of Pb (81.2%) in spiked soil makes water more suitable against other washing solutions. Statistical t-testing showed significant difference in Pb removal efficiency between contaminated and spiked soils for all four washing solutions, reflecting differences in geochemical phases of Pb in both soils. Terminalia mantaly and Panicum maximum showed promising result in soil washing and have potential for application in Pb removal from contaminated soils. However, chemical modifications are needed to enhance and improve on their efficiencies. Similarly, more information is needed to predict and model removal efficiencies when multiple washing steps are applied.

Open access

Faith I. Akinnibosun and Odaro S. Imade

Abstract

This research was performed to ascertain the ubiquity of bacterial pathogens which hyper-produced AmpC β-lactamase enzymes in adult catfish cultured in the Nigerian catfish grow-out pond systems. Phenotypic and molecular methods were used to isolate and identify bacterial pathogens that hyper-produced AmpC β-lactamase enzymes. The AmpC β-lactamase enzymes produced by the bacterial pathogens were subsequently characterized by BLASTX and RPS-BLAST bioinformatics software as well as with the Cn3D molecular modelling software. Findings from the present study indicated that pathogenic bacterial strains which hyper-produced the AmpC β-lactamase enzymes were isolated from 49 catfish samples out of the 54 catfish samples which were examined. The pathogenic bacterial strains were mainly identified as Citrobacter freundii MGH 150, Enterobacter cloacae NG 14, and Enterobacter cloacae subspecies dissolvens HKE 15. The AmpC β-lactamase enzymes produced by the bacterial pathogens were also respectively identified as cephalosporinase hydrolyzing class C CMY-LAT-MOX-ACT-MIR-FOX, CMY2/MIR/ACT/EC family class C beta-lactamase, and CMY2/MIR/ACT/EC family class C beta-lactamase. The presence of AmpC enzymes that are hyper-produced by bacterial pathogens which were isolated from almost all the catfish examined calls for urgent monitoring/surveillance of the Nigerian catfish ponds by the relevant regulatory agencies.