Genotoxic and histotoxic effects of air pollutants at a benzene station on albino rats

Background: This study was designed to explore the hazardous effects of occupational exposure to air pollutants arising from benzene stations.Methods: A total of 48 albino rats were divided into three groups each of sixteen animals. Groups-I and II were kept at a benzene station for 60 and 120 days, respectively; while group-III was kept as a control under normal laboratory conditions. At the end of the experiment, animals were sacrificed and bone marrow samples were taken to investigate the effect of air pollutants at a benzene station on chromosomal aberrations and micronuclei formation. Tissue samples were also picked out to evaluate histotoxic effects of these air pollutants.Results: Results indicated pronounced time-dependent effects because of the work place pollutants. Genetic examination revealed higher frequency of chromosomal aberrations and elevated mitotic index after exposure to air pollutants. Micronuclei formation also increased either in polychromatic or normochromatic erythrocyte due to air pollutants. Histopathological examination revealed congestion of the pulmonary blood vessels with pulmonary edema. Bronchial hyperplasia and metaplasia were also seen in late stage of exposure. The liver showed degenerative changes or even necrosis of hepatocytes, while the kidneys showed congestion of the renal blood vessels and glomerular tufts. Hyalinization of the glomeruli was also detected. The heart showed various mononuclear infiltration and the testes showed degenerative changes of seminiferous tubules. Spleen showed hemosiderosis while testes showed degenerative changes of seminiferous tubules.Conclusions: The findings of the present study indicated that benzene exposure may lead to toxic effects including, genotoxicities and histotoxicities. In order to minimize the predicted toxic effect of occupational exposure to benzene the strict protective measures should be put in consideration

Development of a robust GPS kinetic positioning module for automatic vehicle location and navigation systems

Bibliography: p. 134-140

Development and analysis of wide area differential GPS algorithms

Bibliography: p. 194-204

Novel biphenylidene-thiopyrimidine derivatives as corrosion inhibitors for carbon-steel in oilfield produced water

Abstract The inhibiting efficiency of three newly synthesized organic compounds:5-((4'-(dimethylamino)-[1,1'-biphenyl]-4-yl)methylene)-1,3-diethyl-2-thioxodihydropyrimidine-4,6(1H,5H)-dione (HM-1228), 5-((4'-(dimethylamino)-[1,1'-biphenyl]-4-yl)methylene)-2-thioxodihydropyrimidine-4,6(1H,5H)-dione (HM-1227) and 5-((4'-(dimethylamino)-[1,1'-biphenyl]-4-yl)methylene)pyrimidine-2,4,6(1H,3H,5H)-trione (HM-1226) in oilfield produced water on the corrosion of carbon steel has been examined via electrochemical measurements; potentiodynamic polarization (PDP) and electrochemical impedance (EIS) techniques. The adsorption of these compounds on the surface of carbon steel followed Langmuir isotherm. In addition, the surface morphology of uninhibited and inhibited carbon steel was examined by Atomic Force Microscopy (AFM), observing surface improvement when carbon steel samples exposed to the inhibited corrosive solutions. The average surface roughness (Ra) in oilfield produced water solution in the presence of 0.5 mM of HM-1228 inhibitor was 138.28 nm compared to the uninhibited surface 571.62 nm. To explore the corrosion inhibition mechanism, quantum chemical calculations and Monte Carlo simulations were utilized. The HM-1228 inhibitor demonstrated the highest corrosion inhibition efficiency at 94.8% by PDP measurements. The higher corrosion inhibition of compound HM-1228 can be attributed to the presence of di-N-ethyl groups that enhance both electron donating ability and lipophilic properties