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Showing 4 results for Hatami
Survey of Solvent type and drying of biomass effects on lipid extraction from Nannochloropsis Oculata for biodiesel production
M Malakootian, B Hatami, Sh Dolatshahi, A Rajabzadeh,
Volume 7, Issue 1 (7-2014)
Abstract

Background and Objectives: As a green fuel and environmentally friendly energy, biodiesel has recently attracted much attention and efforts are ongoing to optimizing biodiesel production from microalgae’s. The aim of this study was to determine the appropriate method of dewatering and drying biomass and selecting a suitable organic solvent for extraction lipids from biomass. Materials and Methods: After culturing Nannochloropsis Oculata in Gillard F/2 medium and reaching at the end of the stationary growth phase, algal biomass was separated from aqueous by centrifuge and drying in three methods: fore, air-dried and lyophilized. Lipid extractions of each sample was performed using soxhlet apparatus and three solvents including diethyl ether, n-hexane and n-pentane. At each stage, the quantity and quality of the extracted lipids was determined by gas chromatography. Results: In all three drying methods, palmitic acid and palmitoleic acid were significantly the main fatty acid composition of microalgae. The fatty acid composition of palmitic acid extracted by diethyl ether was significantly more than the other two solvents. Maximum production of triglyceride was observed in air dried and lyophilized (using diethyl ether solvent) microalgae as 75.03 and 76.72 % of fatty acid respectively. Conclusion: The use of lyophilized method for dewatering and drying of biomass and diethyl ether as solvent for the extraction of lipids from biomass yielded more compared with other methods studied in this paper and would be more efficient in research works related to the production of biodiesel from microalgae’s lipid.


Evaluation of copper, zinc, and chromium concentration in landfill soil and hospital waste ash of Shahrekord municipal solid waste landfill
M Hatami Manesh, M Mirzaei, M Gholamali Fard, A.r Riyahi Bakhtiyari, M Sadeghi,
Volume 8, Issue 1 (8-2015)
Abstract

Background and Objectives: one of the most important environmental concerns is heavy metals emissions from human activities to natural ecosystems, particularly transfer to soil. The aims of this study were measured the concentrations of Cu, Zn and Cr in landfill soil and hospital waste ash of Shahrekord municipal solid waste landfill. Materials and Methods: Soil samples were collected from three sites: out of the landfill, municipal landfill and hospital landfill. In each site 2, 1, and 1 stations ware selected respectively and each sample was replicated in three times. Results: We found that there was a significant difference between concentrations of Cu, Zn and Cr in the landfills soil (95% confidence, P <0.05). Furthermore, the highest levels of Zn and Cu were detected in the hospital landfill and also for Cr in the municipal landfills. However, the concentration levels of heavy metals in all of the sites were in order as follows: Zn>Cu>Cr. Conclusion: High concentrations of metals determined in the present study represents the high application of these metals in the structure of municipal and hospital solid wastes and also their inaccurate separation. Thus, awareness about physical and chemical characteristics of municipal and hospital wastes and also the landfill soil is necessary for evaluating their effects on the soil quality and surrounding environments.


Evaluation of toxicity and ecological risk assessment of heavy metals in surface sediments of Sezar River, Lorestan Province
S Mortazavi, M Hatami-Manesh, F Joudaki,
Volume 11, Issue 4 (3-2019)
Abstract
Background and Objective: Considering the toxicity, health and ecological hazards of heavy metals in the environment and the impact on organisms, it looks essential to measure and evaluate their concentrations at the various levels in indigineous ecological strctures. The present study evaluated the concentration of Lead, Nickel, Copper and Zinc and their ecological risk assessment in surface sediments of Sezar River in Lorestan province.
Materials and Methods: 16 stations along the Sezar River were selected for sampling. After preparation and acid digestion of the samples, the concentrations of these metals were determined by Atomic absorbtion.
Results: The average total concentration of the detected metals Ni, Zn, Cu and Pb in the sediment was 71.84 > 40.56> 7.75 > 5.61 mg/kg, respectively. In addition, the evaluation of the Potential acute toxicity, ecological risk, and Pollution Load Index represented a low pollution in the sediments. The environmental risk of the metals in the sediment was evaluated as: Ni> Pb> Cu> Zn. The findings showed that among metals, the contamination factor and modified hazard quotient (mHQ) for nickel was moderate and in the mediun to severe pollution level to the contamination, respectively.
Conclusion: According to the results, it can be concluded that Potential acute toxicity, pollution and ecological risk in the region for investigated metals were low. However, a rapid expansion of various human activities in the area and the pollution of nickel in the river along with the probability of its biological effects require continuous monitoring of the river in order to assess the health risk and its ecological risk.
 

Assessing the capacity of trees and shrubs species to accumulate of particulate matter (PM10, PM2.5 and PM0.2)
M Hatami-Manesh, S Mortazavi, E Solgi, A Mohtadi,
Volume 12, Issue 1 (5-2019)
Abstract
Background and Objective: Today, the presence and increase of particulate matter is one of the serious factors that threaten human health. In the meantime, trees can accumulate airborne particles by their foliage. In this study, the accumulating ability of various PM by the leaf of some tree and shrub species was evaluated in Isfahan.
Materials and Methods: 12 species of trees and shrubs were selected at 8 locations in Isfahan and the total PM, PM10, PM2.5 and PM0.2 were measured using water and chloroform washing methods by paper filters 91, 42 μm, and Polytetra Fluorethylene filters and digital balance.
Results: The results showed that the highest and lowest mean total accumulation of total particulate matter was related to Morus nigra and Salix alba, that were 190.23 ± 23.5 and 11.9 ± 4.42 μg/cm2. In addition, the trend of accumulation of total PM on the leaf surface from the highest to the lowest was: Morus nigra> Platanus orientalis> Ulmus umbraculifera> Morus alba> Acer negundo> Ailanthus altissima> Fraxinus excelsior > Nerium oleander >Robinia pseudoacacia> Cercis siliquastrum> Nerium oleander > Euonymus japonicas> Salix alba and in epicuticular Waxes, Morus nigra> Ulmus umbraculifera > Platanus orientalis > Morus alba> Ailanthus altissima> Acer negundo > Robinia pseudoacacia>Cercis siliquastrum> Fraxinus excelsior > Nerium oleander > Euonymus japonicas> Salix alba.
Conclusion: The results indicated that the ability of different tree species to absorb PM depended on the morphological, physiological and ecological characteristics of the leaf. Finally, among the different species the Morus nigra had the highest ability to capture various PM.
 

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