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Abouian Jahromi Mohammad Jamshidi-Zanjani Ahmad Khodadadi Darban Ahmad 《Environmental Earth Sciences》2020,79(14):1-11
Climate change projections indicate an increase in intense rainfall events with consequent river flooding, which could lead to devastating natural disaster 相似文献
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Hossein Tavallali Shahram Lalehparvar Abdo‐Reza Nekoei Maryam Ghane Jahromi Khodabakhsh Niknam 《洁净——土壤、空气、水》2012,40(6):640-647
A sensitive, reliable, and environmentally friendly method for simple separation and preconcentration of Ag(I) traces in aqueous samples is presented prior to their flame atomic absorption spectrometric determinations. At pH 7.0, Ag(I) was separated with 2‐(2‐methoxyphenyl)benzimidazole (MPBI) as a new complexing agent and floated after adding sodium dodecyl sulfate (SDS) as a foaming reagent. The floated layer was then dissolved in proper amount of concentrated nitric acid in methanol and introduced to the flame atomic absorption spectrometer (FAAS). The effects of pH, concentration of MPBI, type and amount of surfactant as the floating agent, type and amount of eluting agent, and influence of foreign ions on the recovery of the analyte ion were investigated. Also, using a nonlinear curve fitting method, the formation constant of 1.62 × 106 was obtained for Ag(I)–MPBI complex. The analytical curve was linear in the range of 1.8 × 10?7–1.7 × 10?6 mol/L for determination of Ag(I). The relative standard deviation (RSD; N = 10) corresponding to 0.7 × 10?6 mol/L of Ag(I), the limit of detection (10 blanks), and the enrichment factor were obtained as 1.7%, 2.9 × 10?8 mol/L, and 43.0, respectively. The proposed procedure was then applied successfully for determination of silver ions in different water samples. 相似文献
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Fatemeh Amini‐Yekta Mohammad Reza Shokri Abdolvahab Maghsoudlou Hassan Rajabi‐Maham 《Marine Ecology》2019,40(3)
Variations in environmental factors can alter the species distribution pattern in intertidal rocky shores. The Persian Gulf (PG) and the Gulf of Oman (GO) vary substantially with respect to environmental and oceanographic conditions. The abundance and biodiversity of intertidal rocky gastropods in five locations across the northern PG and the GO were compared, and the environmental variables underlying the distribution pattern of these organisms were investigated. A total of 67 gastropod species were identified. The largest average density (294 ind./m2) and diversity (N = 43) for gastropods occurred in the Hotel Lipar station (LIP) located in Chabahar Bay in the GO. Clypeomorus bifasciata (107.43 ind./m2) followed by Cerithium caeruleum (94.67 ind./m2) were the most abundant species. Planaxis sulcatus and Siphonaria spp. occurred in all locations during both sampling occasions. Species richness and abundance of gastropods showed significant differences between LIP and remaining locations. A significant difference was found in assemblage structure across locations. In general, the species richness and density in the locations at GO were significantly larger than those locations in the PG, suggesting that the harsh environmental condition in the PG might be the forcing factor for this diminish. Distinct grouping was observed in both assemblage structure and species composition between locations in the PG and the GO. The spatial and temporal distribution patterns of gastropods assemblages were significantly correlated with variation in salinity and substrate rugosity. 相似文献
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Topography can have significant effects on seismic ground response during an earthquake because topographic irregularities cause considerable differences between the seismic waves emitted by the source and the waves reaching the ground surface. When a seismic motion happens in a topographically irregular area, seismic waves are trapped and reflected between the topographic features. Therefore, the interaction between topographies can amplify seismic ground response. In order to reveal how interaction between topographies influences seismic response, several numerical finite element studies have been performed by using the ABAQUS program. The results show that topographic features a greater distance between the seismic source and the site would cause greater seismic motion amplification and is perceptible for the hills far away from the source and the ridges. Also, site acceleration response is impacted by surrounding topography further than site velocity and displacement response. 相似文献
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A. Karami S. Karbalaei M. Ebrahimi A. Ismail M. F. Jahromi S. L. Simpson P. Eghtesadi Araghi R. P. Lim J. B. Liang 《International Journal of Environmental Science and Technology》2018,15(10):2117-2128
There is a paucity of information about the effects of environmental stressors on nutritional values in fish. This study investigated the effects of the organochlorine pesticide, butachlor, on key indicators of nutritional value in both diploid and triploid African catfish (Clarias gariepinus). Amino acids (AA), fatty acids (FA), and the proximate composition (protein, lipid, moisture, and ash content) in the white muscle of full-sibling juvenile fish were measured following a 21-day exposure to graded butachlor concentrations [mean measured: 26.3, 48.4, and 66.1 µg/L]. No significant differences in AAs, FAs, protein, lipid, moisture, or ash content were observed between unexposed diploid and triploid fish. In diploids, exposure to butachlor significantly altered the concentrations of some of the AAs and FAs, and protein content, when compared to the control group. In triploid fish, however, butachlor treatments had no effect on the AA or proximate composition, but significantly changed the concentration of two individual FAs in the muscle. Butachlor treatments showed fewer changes in the nutritional values of triploid fish. This research is the first to study the nutritional values in any polyploid animals following the exposure to a contaminant. 相似文献
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Thermal springs are attractive geological features interesting for tourists because of their balneological and therapeutic applications. In Iran, the thermal springs surrounding Mount Sabalan are famous and unique in this regard. Two clusters of thermal springs consisting of 16 springs and mostly used as spas occur in Neer and Meshkinshahr areas. In order to investigate the seasonal changes of field and chemical parameters and to trace element concentrations in dry and wet seasons, springs were sampled twice in May and November. Field data including T, EC, pH and Q were measured on-site and major cations and anions were analysed in the laboratory along with 72 trace elements. Cations show the following order of abundance: Na ? Ca ≥ K > Mg and anions follow the order of Cl > HCO3 > SO4. Trace element concentrations indicate that most of the elements show concentrations well beyond the standard guideline values for drinking water. pH, T, spring discharge and elevation are not correlated with each other and with other parameters, indicating that they have had no role on concentrating or depleting trace elements in spring waters. While the two sets of samples were taken within a 6 month interval, the elements and parameters show slight or no variation from the first period to the second and in some cases, they show less than 5 % decrease or increase in the second sampling period. Correlation coefficient and principal component analysis of analytical data indicate that EC, K, Cl, HCO3, As, B, Ba, Br, Li, Na, Rb, Sr and V show very strong mutual correlation coefficients implying their relationship and common source and fate in the hydrothermal fluid that carries them out of the geothermal system. Moreover, they all fall in the component 1 of PCA. This group of elements is supposed to be derived from the magmatic-hydrothermal system through the interaction of hydrothermal fluids with the rocks they have passed through. The mean As value is 160-fold higher than the guideline values (10 μg/l) and Mn and Sb shows an exceedance of 12- and 11.5-fold, respectively. Arsenic shows a variation of 5–5,834 μg/l. Hence, it is supposed that potentially toxic elements may have adverse effects on tourists using the springs as a treatment or recreation. Indeed, the discharge of springs with high values of As and other elements represents a threat for downstream water uses. The higher concentrations of most elements including As, Pb, S, Cl and Sb and the higher pH values found in Neer area springs seem to be more related to an older hydrothermal system present in this area than the Meshkinshahr system that is still active today. 相似文献
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Ertan Pek?en Türker Yas A. Yekta Kayman Co?kun Özkan 《Journal of Applied Geophysics》2011,75(2):305-318
Particle swarm optimization (PSO) is a global search method, which can be used for quantitative interpretation of self-potential data in geophysics. At the result of this process, parameters of a source model, e.g., the electrical dipole moment, the depth of the source, the distance from the origin, the polarization angle and regional coefficients are estimated. This study investigates the results and interpretation of a detailed numerical data of some simple body responses, contaminated and field data. The method is applied to three field examples from Turkey and the results are compared with the previous works. The statistics of particle swarm optimization and the corresponding model parameters are analyzed with respect to the number of generation. We also present the oscillations of the model parameters at the vicinity of the low misfit area. Further, we show how the model parameters and absolute frequencies are related to the total number of PSO iterations. Gaussian noise shifts the low misfit area region from the correct parameter values proportional to the level of errors, which directly affects the result of the PSO method. These effects also give some ambiguity of the model parameters. However, the statistical analyses help to decrease these ambiguities in order to find the correct values. Thus, the findings suggest that PSO can be used for quantitative interpretation of self-potential data. 相似文献
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Ahooghalandari Matin Khiadani Mehdi Jahromi Mina Esmi 《Theoretical and Applied Climatology》2017,128(3-4):845-856
Theoretical and Applied Climatology - Reference evapotranspiration (ET0) is a critical component of water resources management and planning. Different methods have been developed to estimate ET0... 相似文献
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