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1.
Hamid?Reza?PakzadEmail author Mehrdad?Pasandi Siavash?Yeganeh Hamid?Alizadeh Ketek Lahijani 《Environmental monitoring and assessment》2016,188(5):303
Sampling of the offshore seabed sediments of southwestern part of the Caspian Sea was carried out by gravity corer in order to study heavy metal concentration and the physicochemical factors controlling their distribution in the fine-grained fraction. The grain size distribution, amount, and type of clay minerals, total organic carbon (TOC) content, and Eh–pH of the sediments were determined. The average concentrations of the heavy metals in ppm are Mn (563), Cu (207.5), Sr (187), Zn (94), Pb (26.3), Ni (14.5), Co (11.5), Cd (2.56), and Ag (1.04) in their order of abundances. Co and Zn mostly indicate increase in silt-size fraction of the sediments suggesting their probable detrital provenance but the Mn, Ni, Cu, Sr, Pb, Cd, and Ag concentrations show a similar trend to distribution of the clay-size fraction. The concentrations of Mn, Co, and Cd increase with increase in the TOC content but the Cu, Pb, Ni, Ag, and Sr concentrations decrease with increase of the TOC content. The amounts of Zn, Cu, Sr, Pb, Cd, and Ag increase with increase in the CaCO3 content. The calculated enrichment factor indicates that the sediments are very strong to extremely enriched in Ag, significantly enriched in Cu and Cd, and depleted to mineral for Pb, Sr, Co, Ni, and Zn. Variations of the Cu, Sr, Cd, Ag, and Pb concentrations are similar to the clay and CaCO3 distributions. 相似文献
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Mirmohseni A Rastgouy-Houjaghan M 《Journal of environmental science and health. Part. B》2012,47(7):677-686
Quartz crystal nanobalance (QCN) technique is considered as a powerful mass sensitive sensor for monitoring of materials in the sub-nanogram level. In the current study, a method based on QCN technique developed to determine Telone in air. Various coating materials including methyl phenyl silicon, 75% phenyl (OV25) and molecularly imprinted polymer (MIP) were employed. The frequency shift of OV25-modified quartz crystal was found to be linear against organohalogen compounds [Telone (soil fumigant), Koril (Herbicide), Endosulfan (organochlorine insecticide) and Chloroform (solvent)] concentrations in the range of 2.4 to 48 mg L(-1) for Telone vapor and 4.8-24 mg L(-1) for three other vapors. The correlation coefficients for Telone, Koril, Endosulfan and Chloroform were 0.992, 0.996, 0.989 and 0.991, respectively. The principal component analysis was also utilized to process the frequency response data of the organic vapors. Using principal component analysis, it was found that more than 93.85% of the data variance could still be explained by use of two principal components (PC1 and PC2). Subsequently, the successful discrimination of Telone and other compounds was quite possible through the principal component analysis of the transient responses of the OV25-modified electrode. In the second method, a molecularly imprinted polymer-coated sensor for Telone was developed. Molecularly imprinted polymer coated quartz crystal (MIP-QCN) showed a selective response to Telone and gave a linear relationship between frequency shift and amount of Telone from 1 to 48 mg L(-1). In this investigation, the proficiency of MIP-QCN and OV25-modified QCN sensors were compared. 相似文献
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Gharakezloo Yalda Norouzi Nikoo Mohammad Reza Karimi-Jashni Ayoub Mooselu Mehrdad Ghorbani 《Environmental science and pollution research international》2022,29(6):8597-8612
Environmental Science and Pollution Research - Recognizing the vulnerable areas for contamination is a feasible way to protect groundwater resources. The main contribution of the paper is... 相似文献
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Bastami Tahereh Rohani Khaknahad Sina Malekshahi Mehrdad 《Environmental science and pollution research international》2020,27(9):9364-9381
Environmental Science and Pollution Research - In the present work, an ultrasound-assisted reverse-precipitation method was applied as a new approach for the synthesis of CuxO/Fe2O3/MoC. In the... 相似文献
5.
Mehrdad Askarian Peigham Heidarpoor Ojan Assadian 《Waste management (New York, N.Y.)》2010,30(11):2321-2326
BackgroundHealthcare waste comprises all wastes generated at healthcare facilities, medical research centers and laboratories. Although 75–90% of these wastes are classified as household waste posing no potential risk, 10–25% are deemed to be hazardous, representing a potential threat to healthcare workers, patients, the environment and even the general population, if not disposed of appropriately. If hazardous and non-hazardous waste is mixed and not segregated prior to disposal, costs will increase substantially. Medical waste management is a worldwide issue. In Iran, the majority of problems are associated with an exponential growth in the healthcare sector together with low- or non-compliance with guidelines and recommendations. The aim of this study was to reduce the amounts of infectious waste by clear definition and segregation of waste at the production site in Namazi Hospital in Shiraz, Iran.Materials and methodsNamazi Hospital was selected as a study site with an aim to achieving a significant decrease in infectious waste and implementing a total quality management (TQM) method. Infectious and non-infectious waste was weighed at 29 admission wards over a 1-month period.ResultsBefore the introduction of the new guidelines and the new waste management concept, weight of total waste was 6.67 kg per occupied bed per day (kg/occupied bed/day), of which 73% was infectious and 27% non-infectious waste. After intervention, total waste was reduced to 5.92 kg/occupied bed/day, of which infectious waste represented 61% and non-infectious waste 30%. The implementation of a new waste management concept achieved a 26% reduction in infectious waste.ConclusionA structured waste management concept together with clear definitions and staff training will result in waste reduction, consequently leading to decreased expenditure in healthcare settings. 相似文献
6.
David Wainhouse Tristram Wyatt Alun Phillips David R. Kelly Mehrdad Barghian Paul Beech-Garwood David Cross Rex S. Howell 《Chemoecology》1991,2(1):55-63
Summary Adults of the predatory beetleRhizophagus grandis are strongly attracted to both adult and larval frass of its specific prey,Dendroctonus micans, in walking bioassays. Spruce bark and resin are relatively unattractive. Solvent extracts of larval frass that were attractive toR. grandis adults in a flight wind tunnel contained a mixture of monoterpenes of host plant origin. A synthetic mixture of these monoterpenes, (+)—-pinene, (–)—-pinene, -phellandrene,dl limonene and 3-carene, was responsible for 70–80% of the activity of the most attractive extract. We suggest that a blend of monoterpenes in frass acts as a kairomone forR. grandis but that attraction to monoterpenes is only the first of a sequence of behavioural responses that ensures successful host location and identification. 相似文献
7.
Abdolreza Mirmohseni Mehrdad Rastgouy-Houjaghan 《Journal of environmental science and health. Part. B》2013,48(7):677-686
Quartz crystal nanobalance (QCN) technique is considered as a powerful mass sensitive sensor for monitoring of materials in the sub-nanogram level. In the current study, a method based on QCN technique developed to determine Telone in air. Various coating materials including methyl phenyl silicon, 75% phenyl (OV25) and molecularly imprinted polymer (MIP) were employed. The frequency shift of OV25-modified quartz crystal was found to be linear against organohalogen compounds [Telone (soil fumigant), Koril (Herbicide), Endosulfan (organochlorine insecticide) and Chloroform (solvent)] concentrations in the range of 2.4 to 48 mg L?1 for Telone vapor and 4.8–24 mg L?1 for three other vapors. The correlation coefficients for Telone, Koril, Endosulfan and Chloroform were 0.992, 0.996, 0.989 and 0.991, respectively. The principal component analysis was also utilized to process the frequency response data of the organic vapors. Using principal component analysis, it was found that more than 93.85% of the data variance could still be explained by use of two principal components (PC1 and PC2). Subsequently, the successful discrimination of Telone and other compounds was quite possible through the principal component analysis of the transient responses of the OV25-modified electrode. In the second method, a molecularly imprinted polymer-coated sensor for Telone was developed. Molecularly imprinted polymer coated quartz crystal (MIP-QCN) showed a selective response to Telone and gave a linear relationship between frequency shift and amount of Telone from 1 to 48 mg L?1. In this investigation, the proficiency of MIP-QCN and OV25-modified QCN sensors were compared. 相似文献
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Evaluation of exposure to the airborne asbestos in an asbestos cement sheet manufacturing industry in Iran 总被引:1,自引:0,他引:1
Davood Panahi Hossein Kakooei Hossein Marioryad Ramin Mehrdad Mohammad Golhosseini 《Environmental monitoring and assessment》2011,178(1-4):449-454
Iran imports nearly 55,000 tons of Chrysotile asbestos per year and asbestos cement (AC) plants contribute nearly 94% of the total national usage. In the present study, airborne asbestos concentrations during AC sheet manufacturing were measured. The fiber type and its chemical composition were also evaluated by scanning electron microscopy (SEM), with energy-dispersive X-ray analysis. Airborne total fiber concentrations of 45 personal samples were analyzed by phase contrast microscopy. The results have highlighted that 15.5% of samples exceed the threshold limit value (TLV) established the American Conference of Governmental Industrial Hygienists, which is 0.1 fiber per milliliter (f/ml). Personal monitoring of asbestos fiber levels indicated a ranged from 0.02?±?0.01 to 0.16?±?0.03 f/ml. The geometrical mean was 0.05?±?1.36 f/ml, which is considerably lower than the TLV. SEM data demonstrate that the fibrous particles consisted, approximately, of Chrysotile (55.89%) and amphiboles (44.11%). We conclude that the industrial consumption of imported Chrysotile asbestos is responsible for the high airborne amphibole asbestos levels in the AC sheet industry. More research is needed to improve characterization of occupational exposures by fiber size and concentration in a variety of industries. 相似文献