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Seyedeh Masoumeh Fotoukkiaii Zoë Tan Wenxin Xue Nicky Wybouw Thomas Van Leeuwen 《Pest management science》2020,76(3):1154-1163
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Distribution and Contamination of Heavy Metal in the Coastal Sediments of Port Klang, Selangor, Malaysia 总被引：1，自引：0，他引：1
Seyedeh Belin Tavakoly Sany Aishah Salleh Majid Rezayi Naghmeh Saadati Leila Narimany Ghazaleh Monazami Tehrani 《Water, air, and soil pollution》2013,224(4):1-18
The coastal sediments of Port Klang in Malaysia were monitored from November 2009 to October 2010 to evaluate the spatial distribution of heavy metals As, Cu, Cd, Cr, Ni, Pb, Zn, Pb, Mn, Al and Fe. Sediment samples were collected from 21 stations, covering three subsidiary ports, namely West Port, North Port and South Port, at three-month intervals. The geo-accumulation index and the enrichment factor were estimated to assess contamination status based on background values. Additionally, the sediment quality guide was applied to evaluate the adverse biological effects of heavy metals. These results show that the concentrations of some metals, such as As, Cd and Pb were comparatively higher than the background values. This is considered a critical environmental issue for this region. Furthermore, the toxicity estimation indicates that living organisms have a high risk of As exposure. Spatial distribution maps of heavy metals would aid in the identification of pollution sources and vulnerable sites. 相似文献
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Seyyedeh Mahbube Mousavifard Ebrahim Sepehr Naser Davatgar Mir Hassan Rasouli Sadaghiani 《Archives of Agronomy and Soil Science》2013,59(11):1573-1589
The distribution variability of soil electrical conductivity (EC), pH, clay, sand, CaCO3, organic carbon (OC) and available potassium (K) in the Naqade region was investigated using a geostatistical method and Geographical Information System (GIS) technique. Two hundred and eighty-two topsoil (0–30 cm) samples were randomly collected and analyzed. pH and clay followed a normal distribution, whereas sand EC, CaCO3, OC and K were log-transformed. The highest variation was observed for soil EC, and the lowest for soil pH. In the variography analysis, spherical, exponential and gaussian models were best fit on experimental semivariograms. The minimum effective spatial autocorrelation was 1500 m for OC and the maximum effective spatial autocorrelation was 4000 m for sand and K. Strong spatial correlations were noted with sand and CaCO3 (<25%), whereas values were moderate for clay, EC, OC and K (25–75%). Ordinary kriging was utilized for the interpolation of estimated variable determinations in unsampled sites. It was found that soil properties in this study area were strongly influenced by both environmental and natural factors. The results can be used as a source of information for the development and implementation of any further land management and soil and water conservation plans. 相似文献
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Spatial distribution of soil‐available phosphorus and single‐point phosphorus buffering index in the Khoy region,Iran 
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下载免费PDF全文 Knowledge of the amount of nutrients in soil is required to achieve sustainable management. The objective of this study was to assess the variability of soil‐available and single‐point buffering index of phosphorus (P) in the farmlands of the Khoy region, Iran. Composite soil samples (0–30 cm) were collected at 114 locations on regular grid of 1000 m. Some soil physico‐chemical characteristics such as soil texture, soil organic matter (OM) content, soil pH, electrical conductivity (EC), calcium carbonate equivalent (CCE), available P (Pava) and single‐point P sorption index (PSI) were measured. Results showed that all variables in this study have spatial distribution in the effective range of 1500–4800 m. Moreover, experimental semivariograms of all studied variables were best‐fit by spherical and exponential models. Most importantly, kriged maps revealed that a major part of the study area contains high Pava, which is seemingly due to the frequent application of phosphate fertilizers along with poultry manure. Some soils in the western part showed low PSI index; they therefore need more P fertilizer application. In addition, due to the lower PSI value in the eastern half of the study region, applying less fertilizer at more frequent intervals seems to be more beneficial than larger single applications. Eventually, to reduce environmental risks and prevent the loss of natural resources, the method of applying P fertilizer needs to be mainly based on the created PSI distribution map. 相似文献
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Seyedeh Nooshin Banitaba Golchehr Amini Ali Akbar Gharehaghaji Ali Asghar Asgharian Jeddi 《Fibers and Polymers》2017,18(12):2342-2348
This study aims to develop a new approach for fabricating hollow nanofibrous yarns by engineering a triple-layer structure (polyvinyl alcohol (PVA) multifilament core surrounded by a layer of PVA nanofibers and a polylactic acid (PLA) nanofiber outer layer). After fabrication of this 3-layer structure, the core portion was extracted, leaving the outer layer intact after dissolving the PVA nanofibers in water. To determine the optimum thickness of the outer layer, hollow nanofiber yarns with five different thicknesses were produced. A hollow nanofiber yarn was also produced using a common method to enable comparison of the methods. In the common method, a core sheath yarn consisting of a PVA multifilament core and a PLA nanofiber outer layer was fabricated, and a hollow yarn was produced by placing the core yarn in hot water. The results revealed facilitation of core extraction from the yarn body of the new 3-layer structure, which occurred due to rapid dissolution of the middle layer. The wicking behavior in the hollow yarn fabricated using the novel method followed the Locus Washburn equation and that of the hollow yarn produced from the core sheath yarn deviated from it. The results demonstrated that tensile properties of hollow nanofiber yarns were improved by increasing the thickness. Furthermore, hemolysis and cytotoxicity assays indicated that the fabricated hollow nanofibrous structure is non-toxic and blood compatible, indicating its potential for use in biomedical applications such as vascular scaffolds. 相似文献
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Seyedeh Ainaz Shirangi Mohammad Reza Kalbassi Saber Khodabandeh Hojatollah Jafarian Catherine Lorin-Nebel Emilie Farcy Jehan-Hervé Lignot 《Fish physiology and biochemistry》2016,42(6):1741-1754
The effect of abrupt and 5-day gradual salinity transfers from freshwater (FW) to 11 ‰ Caspian Sea brackish water (BW) was investigated in juvenile Persian sturgeon Acipenser persicus with three different weight groups: 1–2 g (1.62 ± 0.27 g), 2–3 g (2.55 ± 0.41 g) and 3–5 g (4.28 ± 0.76 g). Mortality rates, blood osmotic pressure, gill morphology and branchial Na+, K+-ATPase (NKA) activity were measured 4 and 10 days after abrupt transfer and 9 and 15 days after the initial gradual transfer (i.e. 4 and 10 days after reaching Caspian Sea salinity). Fish under 3 g could not survive increased salinity, and the blood osmotic pressure of the remaining surviving fish increased and remained elevated. However, heavier fish were able to survive and successfully acclimate, even to rapid salinity change with osmotic pressure reduced to Caspian Sea osmolality levels. At the gill level, the developmental increase in chloride cell volume and a higher NKA content most probably allow juveniles weighing more than 2 g to sharply increase NKA activity if the fish are transferred to BW. The rapid chloride cell proliferation occurring with increased salinity should strengthen this acclimation response. Therefore, a drastic physiological change occurs when fish weigh more than 2 g that allows migration to higher salinities. The triggering signal on chloride cells must be further investigated in order to optimize this functional step. 相似文献
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Seyedeh Masoumeh Hafezi Kazem Doosthoseini 《林业研究》2014,25(3):667-670
We used silane coupling agents to improve the bonding ability between wheat straw particles and UF resin, and investigated surface properties （wettability and surface roughness） and hardness of parti-cleboard made from UF-bonded wheat straw （Triticum aestivum L.） combined with poplar wood as affected by silane coupling agent content and straw/poplar wood particle ratios. We manufactured one-layered particleboard panels at four different ratios of straw to poplar wood par-ticles （0%, 15%, 30% and 45% wheat straw） and silane coupling agent content at three levels of 0, 5% and 10%. Roughness measurements, average roughness （Ra）, mean peak-to-valley height （Rz）, and root mean square roughness （Rq） were measured on unsanded samples by using a fine stylus tracing technique. We obtained contact angle measurements by using a goniometer connected to a digital camera and computer sys-tem. Boards containing greater amounts of poplar particles had superior hardness compared to control samples and had lower wettability. Panels made with higher amounts of silane had lower Rq values. 相似文献
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