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Faculty of biological sciences, Kharazmi University, Tehran-Iran
To mitigate the growing threat of climate change and develop novel technologies that can eliminate carbon dioxide, the most abundant greenhouse gas derived from the flue gas stream of the fossil fuel-fired power stations, is momentous. The development of carbon capture and sequestration-based technologies may play a significant role in this regard. Carbon fixation mostly occurs by photosynthesizing plants as well as photo and chemoautotrophic microbes that turn the atmospheric carbon dioxide into organic materials via their enzymes. Biofuel can offer a sustainable solution for carbon mitigation. The pragmatic implementation of biofuel production processes is neither cost-effective nor has been proven safe over the long term. Searching for ways to enhance biofuel generation by the employment of genetic engineering is vital. Carbon biosequestration can help to curb the greenhouse effect. In addition, new genomic approaches, which are able to use gene-splicing biotechnology techniques and recombinant DNA technology to produce genetically modified organisms, can contribute to improvement in sustainable and renewable biofuel and biomaterial production from microorganisms. Biopolymers, Biosurfactants, and Biochars are suggested as sustainable future trends. This study aims to pave the way for implementing biotechnology methods to capture carbon and decrease the demand and consumption of fossil fuels as well as the emissions of greenhouse gases. Having a better image of microorganisms' potential role in carbon capture and storage can be prolific in developing powerful techniques to reduce CO2 emissions.
Mohammad Ali Zahed; Elaheh Movahed; Arezoo Khodayari; Saba Zanganeh; Maryam Badamaki. Biotechnology for carbon capture and fixation: Critical review and future directions. Journal of Environmental Management 2021, 293, 112830 .
AMA StyleMohammad Ali Zahed, Elaheh Movahed, Arezoo Khodayari, Saba Zanganeh, Maryam Badamaki. Biotechnology for carbon capture and fixation: Critical review and future directions. Journal of Environmental Management. 2021; 293 ():112830.
Chicago/Turabian StyleMohammad Ali Zahed; Elaheh Movahed; Arezoo Khodayari; Saba Zanganeh; Maryam Badamaki. 2021. "Biotechnology for carbon capture and fixation: Critical review and future directions." Journal of Environmental Management 293, no. : 112830.
A novel strategy of using microalgae Chlorella vulgaris for simultaneous bio-treatment of petrochemical wastewater and lipid production was developed in the present study. Phycoremediation was carried out in 30 days. The profile of fatty acids was identified, and the specifications of biodiesel including saponification value, iodine value, cetane number, long-chain saturated factor, cold filter plugging point, cloud point, allylic position equivalent and bis-allylic position equivalent were predicted by BiodieselAnalyzer® software. Besides, polycyclic aromatic hydrocarbons were determined in both wastewater samples and produced lipid. The observed data showed that biodiesel from C. vulgaris was superior to petrodiesel in terms of suitability in diesel engines. Moreover, contamination of petrochemical wastewater can influence the expression of a variety of genes in algae. To investigate the effectiveness of contamination on the expression of lipid synthesis as well as three photosynthesis genes, a real-time polymerase chain reaction assay was used to quantify transcript levels of PsaB (photosystem I reaction center protein subunit B), psbC (an integral membrane protein component of photosystem II), and rbcL (a large subunit of ribulose-1,5-bisphosphate carboxylase oxygenase). Furthermore, the gene expression level of accD (acetyl-coenzyme A carboxylase carboxyl transferase subunit beta, chloroplastic) was studied to discover the effect of wastewater on lipid production. The results showed that when diluted petrochemical wastewater (50%) was used as a media for C. vulgaris cultivation, these genes expression significantly increased. For 50% diluted wastewater, the maximum removal of BOD, COD, total nitrogen, and total phosphor has been 30.36%, 10.89%, 69.89%, and 92.59%, respectively.
Rozita Madadi; Mohammad Ali Zahed; Ahmad Ali Pourbabaee; Meisam Tabatabaei; Mohammad Reza Naghavi. Simultaneous phycoremediation of petrochemical wastewater and lipid production by Chlorella vulgaris. SN Applied Sciences 2021, 3, 1 -10.
AMA StyleRozita Madadi, Mohammad Ali Zahed, Ahmad Ali Pourbabaee, Meisam Tabatabaei, Mohammad Reza Naghavi. Simultaneous phycoremediation of petrochemical wastewater and lipid production by Chlorella vulgaris. SN Applied Sciences. 2021; 3 (4):1-10.
Chicago/Turabian StyleRozita Madadi; Mohammad Ali Zahed; Ahmad Ali Pourbabaee; Meisam Tabatabaei; Mohammad Reza Naghavi. 2021. "Simultaneous phycoremediation of petrochemical wastewater and lipid production by Chlorella vulgaris." SN Applied Sciences 3, no. 4: 1-10.
Microalgae are a large group of phototrophic microorganisms that convert CO2 into biomass, which can be used as an important source of biofuels. Biofuels have a lot of interesting applications in various industries. The main objective of the current study was to assess the biomass and lipid production, gene expression of acetyl-CoA carboxylase (accD) and ribulose bisphosphate carboxylase large-chain (rbcL), and the lipid content produced by myo-inositol treatment in the microalga Chlorella vulgaris. Three different myo-inositol concentrations (i.e., 50, 100, and 200 mg/L) were added to the algal growth media, and the algal cells were sampled on the day of entering the stationary phase of the growth cycle. Biomass production was increased by increasing the supplement. However, the 200 mg/L concentration of myo-inositol was critical for lipid production. To evaluate the effect of the vitamin on the expression of the accD and rbcL genes, real-time PCR was used. The rbcL gene expression increased in relation to biomass production, i.e., 224.08 times higher than the control. On the other hand, the accD expression at 200 mg/L myo-inositol concentration, as physiological stress, increased, i.e., 95.2 times higher than the control. Therefore, this growth complement can induce biomass and lipid production. Findings of the present study provide valuable insight into determining the biochemical modulation strategies of biomass and lipid production. In this study, two separate controlling systems and two independent promoters were proposed to regulate the transcription of rbcL and accD genes induced by various concentrations of myo-inositol.
Somayeh Eghrari Gayglou; Vida Tafakori; Mohammad Ali Zahed; Atefeh Khamoushi. Two promoters of biodiesel and biomass production induced by different concentrations of myo-inositol in Chlorella vulgaris. Biomass Conversion and Biorefinery 2021, 1 -9.
AMA StyleSomayeh Eghrari Gayglou, Vida Tafakori, Mohammad Ali Zahed, Atefeh Khamoushi. Two promoters of biodiesel and biomass production induced by different concentrations of myo-inositol in Chlorella vulgaris. Biomass Conversion and Biorefinery. 2021; ():1-9.
Chicago/Turabian StyleSomayeh Eghrari Gayglou; Vida Tafakori; Mohammad Ali Zahed; Atefeh Khamoushi. 2021. "Two promoters of biodiesel and biomass production induced by different concentrations of myo-inositol in Chlorella vulgaris." Biomass Conversion and Biorefinery , no. : 1-9.
Antibiotics are frequently applied to treat bacterial infections in humans and animals. However, most consumed antibiotics are excreted into wastewater as metabolites or in their original form. Therefore, removal of antibiotics from aquatic environments is of high research interest. In this study, we investigated the removal of sulfamethoxazole (SMX) and ofloxacin (OFX) with Chaetoceros muelleri, a marine diatom. The optimization process was conducted using response surface methodology (RSM) with two independent parameters, i.e., the initial concentration of antibiotics and contact time. The optimum removal of SMX and OFX were 39.8% (0.19 mg L−1) and 42.5% (0.21 mg L−1) at the initial concentration (0.5 mg L−1) and contact time (6.3 days). Apart from that, the toxicity effect of antibiotics on the diatom was monitored in different SMX and OFX concentrations (0 to 50 mg L−1). The protein (mg L−1) and carotenoid (µg L−1) content increased when the antibiotic concentration increased up to 20 mg L−1, while cell viability was not significantly affected up to 20 mg L−1 of antibiotic concentration. Protein content, carotenoid, and cell viability decreased during high antibiotic concentrations (more than 20 to 30 mg L−1). This study revealed that the use of Chaetoceros muelleri is an appealing solution to remove certain antibiotics from wastewater.
Amin Mojiri; Maedeh Baharlooeian; Mohammad Zahed. The Potential of Chaetoceros muelleri in Bioremediation of Antibiotics: Performance and Optimization. International Journal of Environmental Research and Public Health 2021, 18, 977 .
AMA StyleAmin Mojiri, Maedeh Baharlooeian, Mohammad Zahed. The Potential of Chaetoceros muelleri in Bioremediation of Antibiotics: Performance and Optimization. International Journal of Environmental Research and Public Health. 2021; 18 (3):977.
Chicago/Turabian StyleAmin Mojiri; Maedeh Baharlooeian; Mohammad Zahed. 2021. "The Potential of Chaetoceros muelleri in Bioremediation of Antibiotics: Performance and Optimization." International Journal of Environmental Research and Public Health 18, no. 3: 977.
Globally, petroleum has been the largest source of energy consumption compared to other energy sources such as natural gas and coal. As a result of high demand for petroleum as an energy source, contamination takes place due to maintenance, production, exploration, storage, transportation and accidental release, yielding in substantial ecological impacts. The contaminations of petroleum in the presence of soil have a negative impact on human health and the development of plant growth. According to this, there is an imperative need to investigate on environmental-friendly remediation strategies to eliminate petroleum contaminants in soil. Among different remediation technologies, bioremediation is recognized as a clean soil treatment technology due to its advantages of safety, no secondary pollution, and economy. For bioremediation of contaminated soil, biochar (BC) applications may provide new solution for polluted soil problems. BC has displayed a good potential to remedy soil contaminants owed to its wide availability of the necessary feedstock, sustainable nature, cost-effective feasibility, high efficiency, large internal surface area and desirable physicochemical surface properties. The usage of BC may include sequestration of carbon, improvement fertility of soil, remediation, as well as recycling of agricultural waste. This paper provides a review on current properties and preparation of BC and its usage as an ameliorant, amendment or sorbent for remediation of contaminated soil. Different research and published papers in this field reveal that the potential of biochar for contaminated soil remediation relies on its physical and chemical properties, which are considerably influenced by the feedstocks, pyrolysis conditions and pyrolysis technologies. The results show that the pyrolysis conditions can affect the BC structure and composition and thus its adsorption capacity. Pyrolysis temperature influences the adsorption characteristics of BC by changing the surface functionality, surface area, pore distribution and mineral concentration of BC. It is important to produce BC at optimum pyrolysis temperatures to maximize inorganic and organic contaminant adsorption. The results also indicate that BC obtained through microwave pyrolysis has better yield and quality than those produced from conventional pyrolysis.
Mohammad Ali Zahed; Samira Salehi; Rozita Madadi; Faranak Hejabi. Biochar as a sustainable product for remediation of petroleum contaminated soil. Current Research in Green and Sustainable Chemistry 2021, 4, 100055 .
AMA StyleMohammad Ali Zahed, Samira Salehi, Rozita Madadi, Faranak Hejabi. Biochar as a sustainable product for remediation of petroleum contaminated soil. Current Research in Green and Sustainable Chemistry. 2021; 4 ():100055.
Chicago/Turabian StyleMohammad Ali Zahed; Samira Salehi; Rozita Madadi; Faranak Hejabi. 2021. "Biochar as a sustainable product for remediation of petroleum contaminated soil." Current Research in Green and Sustainable Chemistry 4, no. : 100055.
The aim of this paper was to study biodiesel production from waste cooking oil using a transesterification method. Optimization was achieved by changing process variables, including the oil:alcohol molar ratio and reaction temperature, to maximize biodiesel yield. Optimum variables were identified using Central Composite Face-Centered Design (CCFD) and Response Surface Methodology (RSM). Furthermore, the synergistic and antagonistic effects among process parameters were analyzed. The optimum temperature for the production of biodiesel was identified at 62.8 °C, and the optimum oil:alcohol ratio was 4.3; the combination of these parameters resulted in the highest theoretical efficiency of 96.08% and desirability of 0.608. After evaluating the experimentally produced biodiesel, the study revealed that waste cooking oil can be used as a potential raw material for the production of biofuel.
Mohammad Ali Zahed; Zahra Zakeralhosseini; Leila Mohajeri; Gholamreza Nabi Bidhendi; Saba Mesgari. Multivariable Analysis and Optimization of Biodiesel Production from Waste Cooking Oil. Environmental Processes 2018, 5, 303 -312.
AMA StyleMohammad Ali Zahed, Zahra Zakeralhosseini, Leila Mohajeri, Gholamreza Nabi Bidhendi, Saba Mesgari. Multivariable Analysis and Optimization of Biodiesel Production from Waste Cooking Oil. Environmental Processes. 2018; 5 (2):303-312.
Chicago/Turabian StyleMohammad Ali Zahed; Zahra Zakeralhosseini; Leila Mohajeri; Gholamreza Nabi Bidhendi; Saba Mesgari. 2018. "Multivariable Analysis and Optimization of Biodiesel Production from Waste Cooking Oil." Environmental Processes 5, no. 2: 303-312.
Rhizoremediation is a natural biological base, multifactorial operation treatment method which highly depends to environmental factors especially in terrestrial environment as operation of remediation process. Interaction and relationship between microbial community and plant roots is specific attraction and advantages of this advanced treatment method. Decontamination efficiency and time could be highly manageable by operation and rhizoaugmentation. Rhizoremediation is advanced compact combination of phytoextraction, phytovolatilization, phytotransformation and phytostabilization. High efficiency of pollutants removal, adaptive and wide range of operation and augmentation factors cause of emerging application of this for biodegradable organic compounds and heavy metals. Selection of suitable plant and joining them with comfortable microbial couples is a function which can plane simultaneously removal system. This chapter will present an overview on PAH, TPH, PCB and heavy metal removal and mechanism of decontamination, plant selection and augmentation process.
Hossein Farraji; Nastaein Qamaruz Zaman; Mohammad Ali Zahed; Hamed Faraji; Jatindra Nath Bhakta. Role of Rhizoremediation in Decontaminating Some Hazardous Pollutants. Advances in Environmental Engineering and Green Technologies 2017, 213 -246.
AMA StyleHossein Farraji, Nastaein Qamaruz Zaman, Mohammad Ali Zahed, Hamed Faraji, Jatindra Nath Bhakta. Role of Rhizoremediation in Decontaminating Some Hazardous Pollutants. Advances in Environmental Engineering and Green Technologies. 2017; ():213-246.
Chicago/Turabian StyleHossein Farraji; Nastaein Qamaruz Zaman; Mohammad Ali Zahed; Hamed Faraji; Jatindra Nath Bhakta. 2017. "Role of Rhizoremediation in Decontaminating Some Hazardous Pollutants." Advances in Environmental Engineering and Green Technologies , no. : 213-246.
In the present study, bulk contents of Ni, Zn, Cu, Pb and Mn in urban area of Tehran city are determined. Subsequently, the chemical bonds of metals with various soil fractions are brought out. Chemical partitioning studies revealed that various percentile of Ni, Zn, Cu, Pb and Mn is found in anthropogenic portion of soils. Zinc, Ni, Cu, Pb and Mn fall within “low pollution” class in accordance with index of pollution (I POLL). The trend of anthropogenic share of studied metals in soils of Tehran is Zn (55 %) > Cu (31 %) > Ni and Pb (30 %) > Mn (12 %). The overall potential of studied plants in metal removal from soil is Salvia > Viola > Portulaca. It should be pointed out that roots have higher potential in metal removal from soil when compared with leaf and stem. Lithogenic portion of metals remains intact before and after pot analysis. Thus, phytoremediation is highly dependent on the chemical bonds of metals. Present study showed that metal contents of loosely bonded ions, sulfide bonds and organometallic bonds are reduced after 90 days of plant cultivation. The overall removal trend of studied metals is Zn (16 %) > Cu (14 %) > Ni (11 %) > Pb (7 %) > Mn (6 %). The obtained results show that the anthropogenic portion of metals is reduced after the phytoremediation practice. For instance, the initial anthropogenic portion of Zn (55 %) is changed to 39 % showing an overall reduction of about 16 %. The anthropogenic portions of Cu, Ni, Pb and Mn are also reduced by 14, 11, 7 and 6 %, respectively.
S. Karbassi; M. Malek; T. Shahriari; Mohammad Zahed. Uptake of metals by plants in urban areas. International Journal of Environmental Science and Technology 2016, 13, 2847 -2854.
AMA StyleS. Karbassi, M. Malek, T. Shahriari, Mohammad Zahed. Uptake of metals by plants in urban areas. International Journal of Environmental Science and Technology. 2016; 13 (12):2847-2854.
Chicago/Turabian StyleS. Karbassi; M. Malek; T. Shahriari; Mohammad Zahed. 2016. "Uptake of metals by plants in urban areas." International Journal of Environmental Science and Technology 13, no. 12: 2847-2854.
Different physical, chemical, and biological treatment methods are used to eliminate heavy metals and pollutants from wastewater and landfill leachate. Sequencing batch reactor (SBR) is a type of biological treatment. This study was conducted to study heavy metals elimination from urban wastewater and landfill leachate using an adsorbent, namely powdered ZELIAC (PZ) that improved SBR. PZ consists of portland cement, limestone, rice husk ash, activated carbon, and zeolite. Response surface methodology and central composite design were used to elucidate the nature of the response surface in the experimental plan and determine the optimum settings of the independent variables [aeration rate (L/min), contact time (h), and leachate to wastewater ratio (%; v/v)] and their reactions. To study the aerobic process, four dependent factors (Fe, Mn, Ni, and Cd) were evaluated as reactions. The results indicated that compared with SBR, PZ-SBR removed heavy metals more efficiently. At the optimum contact time (11.70 h), aeration rate (2.87 L/min), and leachate to wastewater ratio (20.13%) in PZ-SBR, removal efficiencies for Fe, Mn, Ni, and Cd were 79.57, 73.38, 79.29, and 76.96%, respectively.
Amin Mojiri; Hamidi Abdul Aziz; Nastaein Qamaruz Zaman; Shuokr Qarani Aziz; Mohammad Ali Zahed. Metals removal from municipal landfill leachate and wastewater using adsorbents combined with biological method. DESALINATION AND WATER TREATMENT 2014, 57, 2819 -2833.
AMA StyleAmin Mojiri, Hamidi Abdul Aziz, Nastaein Qamaruz Zaman, Shuokr Qarani Aziz, Mohammad Ali Zahed. Metals removal from municipal landfill leachate and wastewater using adsorbents combined with biological method. DESALINATION AND WATER TREATMENT. 2014; 57 (6):2819-2833.
Chicago/Turabian StyleAmin Mojiri; Hamidi Abdul Aziz; Nastaein Qamaruz Zaman; Shuokr Qarani Aziz; Mohammad Ali Zahed. 2014. "Metals removal from municipal landfill leachate and wastewater using adsorbents combined with biological method." DESALINATION AND WATER TREATMENT 57, no. 6: 2819-2833.
Samples of surface sediments from the Iranian coast of the Persian Gulf were examined to determine the levels and sources of 15 polycyclic aromatic hydrocarbons (PAHs). Samples were collected from 30 sampling sites and analyzed for PAHs by gas chromatography-mass spectrometry (GC-MS). Total concentrations of PAHs ranged from 93 to 4,077 ng g(-1) dry weight. The PAH composition from 30 sampling sites was dominated by four-ring PAH compounds. Molecular indices based on the ratios of PAH concentrations were used to differentiate PAHs from pyrolitic to petrogenic and mixed origins. The results suggested that the main sources of PAHs in sediments from the studied region were mixed pyrolitic and petrogenic. Furthermore, benthic organisms in most of the investigated areas were not at ecotoxicological risk, according to the results from the effects range low (ERL)/effects range median (ERM) techniques suggested by the US Sediment Quality Guidelines (SQGs).
Roozbeh Mirza; Mehdi Mohammadi; Iraj Faghiri; Ehsan Abedi; Ali Fakhri; Ali Azimi; Mohammad Ali Zahed. Source identification of polycyclic aromatic hydrocarbons (PAHs) in sediment samples from the northern part of the Persian Gulf, Iran. Environmental Monitoring and Assessment 2014, 186, 7387 -7398.
AMA StyleRoozbeh Mirza, Mehdi Mohammadi, Iraj Faghiri, Ehsan Abedi, Ali Fakhri, Ali Azimi, Mohammad Ali Zahed. Source identification of polycyclic aromatic hydrocarbons (PAHs) in sediment samples from the northern part of the Persian Gulf, Iran. Environmental Monitoring and Assessment. 2014; 186 (11):7387-7398.
Chicago/Turabian StyleRoozbeh Mirza; Mehdi Mohammadi; Iraj Faghiri; Ehsan Abedi; Ali Fakhri; Ali Azimi; Mohammad Ali Zahed. 2014. "Source identification of polycyclic aromatic hydrocarbons (PAHs) in sediment samples from the northern part of the Persian Gulf, Iran." Environmental Monitoring and Assessment 186, no. 11: 7387-7398.
Sequencing batch reactor (SBR) is one of the various methods of biological treatments used for treating wastewater and landfill leachate. This study investigated the treatment of landfill leachate and domestic wastewater by adding a new adsorbent (powdered ZELIAC; PZ) to the SBR technique. ZELIAC consists of zeolite, activated carbon, lime stone, rice husk ash, and Portland cement. The response surface methodology and central composite design were used to elucidate the nature of the response surface in the experimental design and describe the optimum conditions of the independent variables, including aeration rate (L/min), contact time (h), and ratio of leachate to wastewater mixture (%; v/v), as well as their responses (dependent variables). Appropriate conditions of operating variables were also optimized to predict the best value of responses. To perform an adequate analysis of the aerobic process, four dependent parameters, namely, chemical oxygen demand (COD), color, ammonia-nitrogen (NH3-N), and phenols, were measured as responses. The results indicated that the PZ-SBR showed higher performance in removing certain pollutants compared with SBR. Given the optimal conditions of aeration rate (1.74 L/min), leachate to wastewater ratio (20%), and contact time (10.31 h) for the PZ-SBR, the removal efficiencies for color, NH3-N, COD, and phenols were 84.11%, 99.01%, 72.84%, and 61.32%, respectively.
Amin Mojiri; Hamidi Abdul Aziz; Nastaein Q. Zaman; Shuokr Qarani Aziz; Mohammad Zahed. Powdered ZELIAC augmented sequencing batch reactors (SBR) process for co-treatment of landfill leachate and domestic wastewater. Journal of Environmental Management 2014, 139, 1 -14.
AMA StyleAmin Mojiri, Hamidi Abdul Aziz, Nastaein Q. Zaman, Shuokr Qarani Aziz, Mohammad Zahed. Powdered ZELIAC augmented sequencing batch reactors (SBR) process for co-treatment of landfill leachate and domestic wastewater. Journal of Environmental Management. 2014; 139 ():1-14.
Chicago/Turabian StyleAmin Mojiri; Hamidi Abdul Aziz; Nastaein Q. Zaman; Shuokr Qarani Aziz; Mohammad Zahed. 2014. "Powdered ZELIAC augmented sequencing batch reactors (SBR) process for co-treatment of landfill leachate and domestic wastewater." Journal of Environmental Management 139, no. : 1-14.
Levels of polychlorinated biphenyls (PCBs) congeners and dichlorodiphenyltrichloroethane and its metabolites (DDTs) were measured in 18 species of fish, crab, shrimp, and bivalve samples collected from the northern region of the Persian Gulf in Iran. The levels of ∑PCBs varied from 259.92 ± 31.04 ng/g to 1648.88 ± 176.96 ng/g in lipid weight. CB118 showed the highest concentration. ∑DDT variations ranged from ND to 570.45 ± 806.74 ng/g in lipid weight. Health risk was assessed by estimating both dietary intakes and screening values (SVs). Daily intake levels were much lower than the Food and Agriculture Organization (FAO)/World Health Organization (WHO) standards for PCBs and DDTs. Based on an average bodyweight of 73 kg and consumption rates of 0.055 kg/person. day, the SVs for the carcinogen and non-carcinogen effects of PCB and DDT were calculated. Average concentrations of PCBs and DDTs showed that the levels of PCBs exceeded the established SV for carcinogens. This finding suggests the need to enhance risk management regarding seafood consumption through public advisory.
Seyedeh Laili Mohebbi-Nozar; Wan Ruslan Ismail; Mohamad Pauzi Zakaria; Mohammad Seddiq Mortazavi; Mohammad Ali Zahed; Ali Jahanlu. Health Risk of PCBs and DDTs in Seafood from Southern Iran. Human and Ecological Risk Assessment: An International Journal 2014, 20, 1164 -1176.
AMA StyleSeyedeh Laili Mohebbi-Nozar, Wan Ruslan Ismail, Mohamad Pauzi Zakaria, Mohammad Seddiq Mortazavi, Mohammad Ali Zahed, Ali Jahanlu. Health Risk of PCBs and DDTs in Seafood from Southern Iran. Human and Ecological Risk Assessment: An International Journal. 2014; 20 (5):1164-1176.
Chicago/Turabian StyleSeyedeh Laili Mohebbi-Nozar; Wan Ruslan Ismail; Mohamad Pauzi Zakaria; Mohammad Seddiq Mortazavi; Mohammad Ali Zahed; Ali Jahanlu. 2014. "Health Risk of PCBs and DDTs in Seafood from Southern Iran." Human and Ecological Risk Assessment: An International Journal 20, no. 5: 1164-1176.
Warm mix asphalt using Sasobit® (Sasol Wax Company, Sasolburg, South Africa) is a new technology to reduce construction temperatures of asphalt mixes. This article presents the rheological properties of Sasobit-modified asphalt binder at high temperatures using response surface methodology. The results showed that the temperature at which the asphalt binder was blended with Sasobit had no effect on the high-temperature properties of Sasobit-modified asphalt binder, including viscosity and viscosity–temperature susceptibility, at each aging state. All empirical viscosity and aging models of Sasobit-modified asphalt binder follow second-order polynomial trends with test temperature, Sasobit contents, and their interactions at each aging condition.
Ali Jamshidi; M. O. Hamzah; M. A. Zahed. Rheological Evaluation and Modeling of Sasobit®-Modified Asphalt Binder at High Temperatures. Petroleum Science and Technology 2013, 31, 1574 -1584.
AMA StyleAli Jamshidi, M. O. Hamzah, M. A. Zahed. Rheological Evaluation and Modeling of Sasobit®-Modified Asphalt Binder at High Temperatures. Petroleum Science and Technology. 2013; 31 (15):1574-1584.
Chicago/Turabian StyleAli Jamshidi; M. O. Hamzah; M. A. Zahed. 2013. "Rheological Evaluation and Modeling of Sasobit®-Modified Asphalt Binder at High Temperatures." Petroleum Science and Technology 31, no. 15: 1574-1584.
Amin Mojiri; Hamidi Abdul Aziz; Mohammad Ali Zahed; Shuokr Qarani Aziz; M. Razip B. Selamat. Phytoremediation of Heavy Metals from Urban Waste Leachate by Southern Cattail (Typha domingensis). International Journal of Scientific Research in Environmental Sciences 2013, 63 -70.
AMA StyleAmin Mojiri, Hamidi Abdul Aziz, Mohammad Ali Zahed, Shuokr Qarani Aziz, M. Razip B. Selamat. Phytoremediation of Heavy Metals from Urban Waste Leachate by Southern Cattail (Typha domingensis). International Journal of Scientific Research in Environmental Sciences. 2013; ():63-70.
Chicago/Turabian StyleAmin Mojiri; Hamidi Abdul Aziz; Mohammad Ali Zahed; Shuokr Qarani Aziz; M. Razip B. Selamat. 2013. "Phytoremediation of Heavy Metals from Urban Waste Leachate by Southern Cattail (Typha domingensis)." International Journal of Scientific Research in Environmental Sciences , no. : 63-70.
Mohammad A. Zahed; Hamidi Abdul Aziz; Mohamed H. Isa; Leila Mohajeri. Response Surface Analysis to Improve Dispersed Crude Oil Biodegradation. CLEAN – Soil, Air, Water 2011, 40, 262 -267.
AMA StyleMohammad A. Zahed, Hamidi Abdul Aziz, Mohamed H. Isa, Leila Mohajeri. Response Surface Analysis to Improve Dispersed Crude Oil Biodegradation. CLEAN – Soil, Air, Water. 2011; 40 (3):262-267.
Chicago/Turabian StyleMohammad A. Zahed; Hamidi Abdul Aziz; Mohamed H. Isa; Leila Mohajeri. 2011. "Response Surface Analysis to Improve Dispersed Crude Oil Biodegradation." CLEAN – Soil, Air, Water 40, no. 3: 262-267.
Landfill leachate is one of the most recalcitrant wastes for biotreatment and can be considered a potential source of contamination to surface and groundwater ecosystems. In the present study, Fenton oxidation was employed for degradation of stabilized landfill leachate. Response surface methodology was applied to analyze, model and optimize the process parameters, i.e. pH and reaction time as well as the initial concentrations of hydrogen peroxide and ferrous ion. Analysis of variance showed that good coefficients of determination were obtained (R2 > 0.99), thus ensuring satisfactory agreement of the second-order regression model with the experimental data. The results indicated that, pH and its quadratic effects were the main factors influencing Fenton oxidation. Furthermore, antagonistic effects between pH and other variables were observed. The optimum H2O2 concentration, Fe(II) concentration, pH and reaction time were 0.033 mol/L, 0.011 mol/L, 3 and 145 min, respectively, with 58.3% COD, 79.0% color and 82.1% iron removals.
Soraya Mohajeri; Hamidi Abdul Aziz; Mohammad Zahed; Leila Mohajeri; Mohammed Jk Bashir; Shuokr Qarani Aziz; Mohd Nordin Adlan; Mohamed Hasnain Isa. Multiple responses analysis and modeling of Fenton process for treatment of high strength landfill leachate. Water Science and Technology 2011, 64, 1652 -1660.
AMA StyleSoraya Mohajeri, Hamidi Abdul Aziz, Mohammad Zahed, Leila Mohajeri, Mohammed Jk Bashir, Shuokr Qarani Aziz, Mohd Nordin Adlan, Mohamed Hasnain Isa. Multiple responses analysis and modeling of Fenton process for treatment of high strength landfill leachate. Water Science and Technology. 2011; 64 (8):1652-1660.
Chicago/Turabian StyleSoraya Mohajeri; Hamidi Abdul Aziz; Mohammad Zahed; Leila Mohajeri; Mohammed Jk Bashir; Shuokr Qarani Aziz; Mohd Nordin Adlan; Mohamed Hasnain Isa. 2011. "Multiple responses analysis and modeling of Fenton process for treatment of high strength landfill leachate." Water Science and Technology 64, no. 8: 1652-1660.
Central composite design (CCD) and response surface methodology (RSM) were employed to optimize four important variables, i.e. amounts of oil, bacterial inoculum, nitrogen and phosphorus, for the removal of selected n-alkanes during bioremediation of weathered crude oil in coastal sediments using laboratory bioreactors over a 60 day experimentation period. The reactors contained 1 kg soil with different oil, microorganisms and nutrients concentrations. The F Value of 26.89 and the probability value (P < 0.0001) demonstrated significance of the regression model. For crude oil concentration of 2, 16 and 30 g per kg sediments and under optimized conditions, n-alkanes removal was 97.38, 93.14 and 90.21% respectively. Natural attenuation removed 30.07, 25.92 and 23.09% n-alkanes from 2, 16 and 30 g oil/kg sediments respectively. Excessive nutrients addition was found to inhibit bioremediation.
Leila Mohajeri; Hamidi Abdul Aziz; Mohammad Zahed; Soraya Mohajeri; Shamsul Rahman Mohamed Kutty; Mohamed Hasnain Isa. Response surface analysis and modeling of n-alkanes removal through bioremediation of weathered crude oil. Water Science and Technology 2011, 63, 618 -626.
AMA StyleLeila Mohajeri, Hamidi Abdul Aziz, Mohammad Zahed, Soraya Mohajeri, Shamsul Rahman Mohamed Kutty, Mohamed Hasnain Isa. Response surface analysis and modeling of n-alkanes removal through bioremediation of weathered crude oil. Water Science and Technology. 2011; 63 (4):618-626.
Chicago/Turabian StyleLeila Mohajeri; Hamidi Abdul Aziz; Mohammad Zahed; Soraya Mohajeri; Shamsul Rahman Mohamed Kutty; Mohamed Hasnain Isa. 2011. "Response surface analysis and modeling of n-alkanes removal through bioremediation of weathered crude oil." Water Science and Technology 63, no. 4: 618-626.
Hydrocarbon pollution in marine ecosystems occurs mainly by accidental oil spills, deliberate discharge of ballast waters from oil tankers and bilge waste discharges; causing site pollution and serious adverse effects on aquatic environments as well as human health. A large number of petroleum hydrocarbons are biodegradable, thus bioremediation has become an important method for the restoration of oil polluted areas. In this research, a series of natural attenuation, crude oil (CO) and dispersed crude oil (DCO) bioremediation experiments of artificially crude oil contaminated seawater was carried out. Bacterial consortiums were identified as Acinetobacter, Alcaligenes, Bacillus, Pseudomonas and Vibrio. First order kinetics described the biodegradation of crude oil. Under abiotic conditions, oil removal was 19.9% while a maximum of 31.8% total petroleum hydrocarbons (TPH) removal was obtained in natural attenuation experiment. All DCO bioreactors demonstrated higher and faster removal than CO bioreactors. Half life times were 28, 32, 38 and 58 days for DCO and 31, 40, 50 and 75 days for CO with oil concentrations of 100, 500, 1000 and 2000 mg/L, respectively. The effectiveness of Corexit 9500 dispersant was monitored in the 45 day study; the results indicated that it improved the crude oil biodegradation rate.
Mohammad Ali Zahed; Hamidi Abdul Aziz; Mohamed Hasnain Isa; Leila Mohajeri; Soraya Mohajeri; Shamsul Rahman Mohamed Kutty. Kinetic modeling and half life study on bioremediation of crude oil dispersed by Corexit 9500. Journal of Hazardous Materials 2011, 185, 1027 -1031.
AMA StyleMohammad Ali Zahed, Hamidi Abdul Aziz, Mohamed Hasnain Isa, Leila Mohajeri, Soraya Mohajeri, Shamsul Rahman Mohamed Kutty. Kinetic modeling and half life study on bioremediation of crude oil dispersed by Corexit 9500. Journal of Hazardous Materials. 2011; 185 (2-3):1027-1031.
Chicago/Turabian StyleMohammad Ali Zahed; Hamidi Abdul Aziz; Mohamed Hasnain Isa; Leila Mohajeri; Soraya Mohajeri; Shamsul Rahman Mohamed Kutty. 2011. "Kinetic modeling and half life study on bioremediation of crude oil dispersed by Corexit 9500." Journal of Hazardous Materials 185, no. 2-3: 1027-1031.
To determine the influence of nutrients on the rate of biodegradation, a five-level, three-factor central composite design (CCD) was employed for bioremediation of seawater artificially contaminated with crude oil. Removal of total petroleum hydrocarbons (TPH) was the dependent variable. Samples were extracted and analyzed according to US-EPA protocols. A significant (R2 = 0.9645, P < 0.0001) quadratic polynomial mathematical model was generated. Removal from samples not subjected to optimization and removal by natural attenuation were 53.3% and 22.6%, respectively. Numerical optimization was carried out based on desirability functions for maximum TPH removal. For an initial crude oil concentration of 1 g/L supplemented with 190.21 mg/L nitrogen and 12.71 mg/L phosphorus, the Design-Expert® software predicted 60.9% hydrocarbon removal; 58.6% removal was observed in a 28-day experiment.
Mohammad Zahed; Hamidi Abdul Aziz; Mohamed Hasnain Isa; Leila Mohajeri; Soraya Mohajeri. Optimal conditions for bioremediation of oily seawater. Bioresource Technology 2010, 101, 9455 -9460.
AMA StyleMohammad Zahed, Hamidi Abdul Aziz, Mohamed Hasnain Isa, Leila Mohajeri, Soraya Mohajeri. Optimal conditions for bioremediation of oily seawater. Bioresource Technology. 2010; 101 (24):9455-9460.
Chicago/Turabian StyleMohammad Zahed; Hamidi Abdul Aziz; Mohamed Hasnain Isa; Leila Mohajeri; Soraya Mohajeri. 2010. "Optimal conditions for bioremediation of oily seawater." Bioresource Technology 101, no. 24: 9455-9460.
Response surface methodology (RSM) was employed to optimize nitrogen and phosphorus concentrations for removal of n-alkanes from crude oil contaminated seawater samples in batch reactors. Erlenmeyer flasks were used as bioreactors; each containing 250 mL dispersed crude oil contaminated seawater, indigenous acclimatized microorganism and different amounts of nitrogen and phosphorus based on central composite design (CCD). Samples were extracted and analyzed according to US-EPA protocols using a gas chromatograph. During 28 days of bioremediation, a maximum of 95% total aliphatic hydrocarbons removal was observed. The obtained Model F-value of 267.73 and probability F < 0.0001 implied the model was significant. Numerical condition optimization via a quadratic model, predicted 98% n-alkanes removal for a 20-day laboratory bioremediation trial using nitrogen and phosphorus concentrations of 13.62 and 1.39 mg/L, respectively. In actual experiments, 95% removal was observed under these conditions.
Mohammad Zahed; Hamidi Abdul Aziz; Leila Mohajeri; Soraya Mohajeri; Shamsul Rahman Mohamed Kutty; Mohamed Hasnain Isa. Application of statistical experimental methodology to optimize bioremediation of n-alkanes in aquatic environment. Journal of Hazardous Materials 2010, 184, 350 -356.
AMA StyleMohammad Zahed, Hamidi Abdul Aziz, Leila Mohajeri, Soraya Mohajeri, Shamsul Rahman Mohamed Kutty, Mohamed Hasnain Isa. Application of statistical experimental methodology to optimize bioremediation of n-alkanes in aquatic environment. Journal of Hazardous Materials. 2010; 184 (1):350-356.
Chicago/Turabian StyleMohammad Zahed; Hamidi Abdul Aziz; Leila Mohajeri; Soraya Mohajeri; Shamsul Rahman Mohamed Kutty; Mohamed Hasnain Isa. 2010. "Application of statistical experimental methodology to optimize bioremediation of n-alkanes in aquatic environment." Journal of Hazardous Materials 184, no. 1: 350-356.