Time filter

Source Type

Lalevic B.,University of Belgrade | Raicevic V.,University of Belgrade | Kikovic D.,University of Tirana | Jovanovic L.,Educons University | And 4 more authors.
International Journal of Environmental Research | Year: 2012

Methyl tertiary butyl ether (MTBE) belongs to the group of gasoline oxygenates and persistent environment contaminants, and shows potential for biodegradation in aerobic and anaerobic conditions, through application of pure microbial cultures. Presented research shows that indigenous bacterial isolates 6sy and 24p, selected from oil hydrocarbons-contaminated environments, were capable of utilizing MTBE as sole carbon and energy source. Based on 16S rDNA sequence analysis, bacterial isolates 6sy and 24p were identified as Staphylococcus saprophyticus subsp. saprophyticus and Pseudomonas sp., respectively. The MTBE biodegradation rate was affected by longevity of incubation period and initial MTBE concentration. After 3 weeks of incubation at 25°C in a dark, the removal rates of initial 25 and 125 ppm MTBE concentrations by Staphylococcus saprophyticus 6sy were found to be 97, and 63%, respectively, while efficiency of Pseudomonas sp. in degradation of indicated concentrations was 96, and 40%, respectively. Both bacterial isolates were able to grow in MTBE-containing growth medium. Highest growth rate of bacterial isolates was observed at the end of incubation period. The presented results indicated the potential of these bacterial isolates in bioremediation of MTBE-contaminated environments.

Nematollahi O.,Isfahan University of Technology | Hoghooghi H.,Isfahan University of Technology | Rasti M.,Jami Institute of Technology
Renewable and Sustainable Energy Reviews | Year: 2016

The energy security and supplies of energy are the key components for progressing countries. Renewable energy resources are rapidly being recognized as clean sources of energy to withstand damages to environment and to avoid future crisis. In this study, energy consumption and energy demands in the progressing Middle East countries are reviewed. First, the growth of energy consumption of the region through recent years is presented which show the rapidly growing energy demand in the Middle East countries. Second, by using RETScreen software data, the potential of the main renewable energies of solar and wind resources are evaluated. Results showed that the Middle East region have a very good potential for using renewable energies. Results are presented as GIS maps of wind speed, wind power density and solar radiation intensity. With using the GIS maps, the great locations for utilizing solar or wind energies are identified. The presented GIS maps may facilitate development of hybrid solar and wind systems within the Middle East region. © 2015 Elsevier Ltd.All rights reserved.

Keyvanfar A.,University of Technology Malaysia | Majid M.Z.A.,University of Technology Malaysia | Shafaghat A.,University of Technology Malaysia | Lamit H.,University of Technology Malaysia | And 6 more authors.
Desalination and Water Treatment | Year: 2014

The importance of enhancing group decision-making and involving different professionals in decision-making process is a challenging issue in diverse disciplines, engineering, medicine, and also biotechnology. Literature review highlights the basic needs of integrative group decision-making. However, such an integrative group decision-making has not been yet applied in biology and biotechnology areas of research. Using an appropriate decision-making model will aid researchers in accurate experimental decision-making process. In this regard, this study developed an integrative group decision-making model called "Grounded-Group Decision Making (GGDM)" model. The current body of knowledge in group decision-making methods was investigated to understand shortcomings and constrains faced by previous researchers. Accordingly, this study developed the GGDM model which was specifically applied in biological self-healing concrete construction process. As a case of application, the GGDM was applied to validate constructability of diverse inoculation methods in biological self-healing concrete construction, including, vascular network, encapsulation, silica gel, active carbon, and direct use. The GGDM model was implemented within three (3) decision-making sessions. In conclusion, GGDM model provided considerably more accurate, integrative, and consensus-value-based results in validation of inoculation methods. In conclusion, "Adaptation" and "Benchmarking" methods were the most suitable methods in biological self-healing concrete construction process. Moreover, establishment of GGDM model will aid software development in biological decision-making process design in future. © 2013 Balaban Desalination Publications.

Fulazzaky M.A.,University of Technology Malaysia | Talaiekhozani A.,Jami Institute of Technology | Abd Majid M.Z.,University of Technology Malaysia
Ecological Engineering | Year: 2016

Formaldehyde (FA) is one of toxic, mutagen, suspected carcinogen and teratogen pollutants presented in contaminated air and might be commonly released from a wide range of the industrial activities. Even though many studies have been made to remove FA from synthetic contaminated air stream (SCAS) using a biotrickling filter reactor (BTFR), the mechanisms of FA removal by a BTFR treatment process must to be verified. The aim of this study was to perform the laboratory-scale BTFR experiments to remove FA from the SCAS during a period of 21 days after passing an adaptation phase of 90 days. The mechanisms of FA removal from SCAS in biofilter must pass through two successive stages: (1) the first diffuses FA from gas phase to aqueous phase to form formic acid and methanol and (2) the second guarantees that the predominant microorganisms are able to metabolise the chemicals-derived FA from aqueous phase for growth and maintenance of life. The research findings may lead to better understanding of the BTFR design and operations to reduce air pollutants in order to maintain or improve air quality. © 2016 Elsevier B.V.

Talaie A.R.,Jami Institute of Technology | Jafaarzahe N.,Health Science University | Talaie M.,University of Isfahan | Beheshti M.,University of Isfahan
Journal of Zanjan University of Medical Sciences and Health Services | Year: 2010

Background and Objective: Oil pollutions are one of the most important environmental problems worldwide that researchers have tried different methods for its degradation. In this regards biological methods attracted the attention of the researchers more than other methods. The main objective of this study was to find microorganisms that could degrade aromatic components in the floating crude oil. Materials and Methods: In order to find such microorganisms, some samples were taken from areas contaminated by petroleum compounds. Microorganisms that could live with crude oil as sole carbon source were isolated. From these samples 14 microorganisms isolated which all were bacteria. The variations of aromatic compounds concentration were measured by gas chromatography method. Results: Among 14 microorganisms two microorganisms that called A-3 and A-14 had more ability and degraded the aromatic components 89% and 86% respectively. By microbiological techniques it was found that A-14 is pseudomonas aerogenusa. Conclusion: The results of this study showed that biodegradation of aromatic compounds that are one of the must toxic materials in crude oil are possible. Also indicated that some oil-degrading microorganisms exist in the nature that do not need to adaptation for biodegradation of oily compounds.

Discover hidden collaborations