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191.
Mostafa Baniasadi Mohammad Reza Zare' Mehrjordi Hossein Mehrabi Boshrabadi Hamid Reza Mirzaei Khalilabad Abbas Rezaei Estakhrooye 《Ground water》2020,58(4):560-570
In recent decades, increased extraction of groundwater for human and agriculture consumption has led to a substantial drop in groundwater level in large areas of across the world. Declining groundwater levels is a serious problem in itself and has multiple economic, social, cultural, political, security-related, and environmental externalities. The negative economic-environmental externalities of overextraction of groundwater in the Orzouiyeh plain in the Kerman Province, Iran, were evaluated using methods such as replacement cost, production function, market prices, shadow price, and the value of the input marginal product. After evaluating externalities, the Positive Mathematical Programming method was used to evaluate different water policies to reduce the consumption of groundwater. The total economic losses due to the externalities were calculated to equal 2.8 U.S. million dollars. The damages caused by environmental externalities were calculated to equal 436.1 U.S. million dollars. The results related to the positive planning model show that the best policy among different options, such as deficit irrigation policy or combined policies, involves implementation of pressurized irrigation systems. 相似文献
192.
Mansourpoor Mojtaba Azin Reza Osfouri Shahriar Izadpanah Amir Abbas Saboori Rahmatallah 《Natural Resources Research》2019,28(4):1609-1617
Natural Resources Research - In this work, we studied the feasibility of using disulfide oil (DSO) as a solvent for wax prevention in pipelines. Several tests were carried out to determine the... 相似文献
193.
Hesni Majid Askari Rezaie-Atagholipour Mohsen Zangiabadi Somaye Tollab Mohammad Amin Moazeni Mostaf Jafari Hosein Matin Mohammad Talebi Zafarani Ghasem Ghorbanzadeh Shojaei Maht Motlaghnejad Abbas 《海洋学报(英文版)》2019,38(12):43-51
Iranian nesting populations of the critically endangered hawksbill turtle(Eretmochelys imbricate) are some of the most important in the Indian Ocean. In this study, four of the most important hawksbill nesting grounds in the Persian Gulf, situated within three Iranian marine protected areas, were surveyed during nesting season,including Nakhiloo, Ommolgorm and Kharko Islands and the mainland beaches of the Naiband Marine-Coastal National Park(NMCNP). We present GIS maps of these key nesting grounds and describe sand texture of key nesting zones, along with conservation recommendations. About 9.2(28.3%) out of 32.5 km of all shores surveyed in this study were used by nesting hawksbill turtles follows: Nakhiloo: 1.4 km(52% of potential nesting area);Ommolgorm: 1.94 km(40%); Kharko: 3.4 km(28%), and NMCNP: 2.46 km(18.9%). The average nesting density was calculated as 131 nests/km at Nakhiloo, 76 nests/km at Ommolgorm, 7 nests/km at Kharko, and 15 nests per km at NMCNP. Highest nesting density was observed in Nakhiloo and Ommolgorm. It is thought that high hawksbill nesting density in these islands seems likely a result of limiting adequate nesting shores rather than the size of population, and also low density in Kharko and NMCNP more related to past and current pressures and low population density. With the exception of Ommolgorm Island, sands at the nesting grounds were well sorted.Grain size indicated that female hawksbill turtles in the Iranian Persian Gulf nest in sands that are generally mixed, with mean grain size ranging from coarse sands(0.4Φ;~0.5–1 mm) to fine sands(2Φ;~0.25 mm). We provide and discuss conservation recommendations and suggestions for future. 相似文献
194.
The stochastic method for finite faults is applied to simulate the ground motion of the 12 October 1992, m
b
= 5.9, Dahshour earthquake. The method includes discritization of the fault plane into certain number of subfaults, and a
ω-squared spectrum is assigned to each of them. Contributions from all subfaults are then empirically attenuated to the observation
sites, where they are summed to produce the synthetic acceleration time-history. The method is first tested against its ability
of reproducing the recording at Kottamya station. The calibrated model is then applied to calculate the synthetics at a large
number of grid points covering the area around the fault plane. Simulated peak values are subsequently used to produce the
synthetic peak horizontal acceleration map for the area.
We compare the peak horizontal acceleration with the attenuation laws proposed for Egypt as well as the macroseismic intensity
map of the 1992 Dahshour earthquake. The peak horizontal acceleration contours estimated using the calibrated model are mostly
consistent with the observed intensity values and evidences of strong ground motions. Our results encourage the application
of the approach as a supplementary tool for site-specific strong ground motion prediction. 相似文献
195.
The Zargoli granite, which extends in a northeast–southwest direction, intrudes into the Eocene–Oligocene regional metamorphic flysch‐type sediments in the northwest of Zahedan. This pluton, based on modal and geochemical classification, is composed of biotite granite and biotite granodiorite, was contaminated by country rocks during its emplacement, and is slightly changed to more aluminous. The SiO2 content of these rocks range from 62.4 to 66 wt% with an alumina saturation index of Shand [molar Al2O3/(CaO + Na2O + K2O)] ~ 1.1. Most of its chemical variations could be explained by fractionation or heterogeneous distribution of biotite. The features of the rocks resemble those which are typical to post‐collisional granitoids. Chondrite‐normalized rare‐earth element patterns of these rocks are fractionated at (La/Lu)N = 2.25–11.82 with a pronounced negative Eu anomaly (Eu/Eu* = 3.25–5.26). Zircon saturation thermometry provides a good estimation of magma temperatures (767.4–789.3°C) for zircon crystallization. These characteristics together with the moderate Mg# [100Mg/(Mg + Fe)] values (44–55), Fe + Mg + Ti (millications) = 130–175, and Al–(Na + K + 2Ca) (millications) = 5–50 may suggest that these rocks have been derived from the dehydration partial melting of quartz–feldspathic meta‐igneous lower crust. 相似文献
196.
Phenolic endocrine disrupting chemicals (EDCs) in Anzali Wetland, Iran: elevated concentrations of 4-nonylphenol, octhylphenol and bisphenol A 总被引:2,自引:0,他引:2
Mortazavi S Bakhtiari AR Sari AE Bahramifar N Rahbarizade F 《Marine pollution bulletin》2012,64(5):1067-1073
We have studied the distribution and value of phenolic endocrine disrupting chemicals (EDCs) in surface sediment samples taken from Anzali Wetland, Iran. These samples were collected from 22 stations during the time span of June-May 2010. In each of the sampling stations, we detected 4-nonylphenol (4-NP), octylphenol (OP), and bisphenol A (BPA) with maximal concentrations of 29, 4.3, and 7 μg g(-1) dry weight (dw), respectively. High levels of alkylphenols (APs) and BPA were also found near urban areas. Furthermore there were no significant differences between those stations in terms of the detected levels. One of the important factors in controlling the fate of these compounds in the aquatic environment appeared to be Total Organic Carbon (TOC). Hierarchical cluster analysis showed differences in the biomarker characteristics of EDCs and TOC between the stations. Our findings indicate that EDCs are ubiquitous in sediments from northeast Wetlands of Iran, contaminating the aquatic habitats in this area. 相似文献
197.
Mostafa Yuness Amer. Mohamed Hyam Nazmy Mona Moustafa Moustafa Abd El-hady 《Stochastic Environmental Research and Risk Assessment (SERRA)》2016,30(1):167-174
Activity size distribution of the short-lived radon progeny in indoor air was measured continuously over several weeks. Two different measurement techniques were used: a direct measurement with a low-pressure Berner cascade impactor for attached fraction of 214Pb and 214Bi (≥100 nm) and an indirect determination based on measurement with a wire screen diffusion battery (unattached fraction 0.5–5 nm, 218Po, 214Pb). In parallel, the meteorological parameters like temperature, humidity were registered. Measured activity size distribution of radon progeny can be approximated by a sum of three log-normal distributions modes (nucleation, accumulation and coarse). The greatest activity fraction was adsorbed on aerosol particles in the accumulation size range (100–1000 nm) with activity median aerodynamic diameters (AMADa) and geometric standard deviations (GSD a ) values of 250–500 nm, and 1.5–3.5, respectively. The influence of the weather conditions on the activity of the accumulation particles was not significant. In contrast to the results of measurements a small but significant fraction of the radon progeny (average value 5 %) was attached to coarse particles (>1000 nm). This fraction varied between 0 and 10 %. On the other hand, although the amount of unattached activities not more 10 % of the total activity, but is considered to yield about 50 % of the total radiation dose. The mean thermodynamic equivalent diameters of 218Po and 214Pb were determined to be 1.28 and 1.30 nm with relative mean geometric standard deviations of 1.30 and 1.24, respectively. Based on the obtained results of radon progeny size distributions (attached and unattached), the total deposition fractions of the human lung were evaluated by using a lung deposition model. 相似文献
198.
This paper is devoted to the thermal evolution of shear-free charged gravitating compact objects which undergoes exhausted its inner heat during gravitational collapse. The evaluation equations have been formulated by applying the perturbation of first order to Einstein–Maxwell equations and Catteno-type heat transportation equation. We show that the temperature gradient (induced in the system owing to external effects), sufficiently depends upon multiple of relaxation time and total time during which the gravitating system oscillates. By taking some particular examples of nuclear matter, it has been noted that at a particular value of luminosity, the change in existing thermal profile is greater corresponding to higher values of times during which a system comes to rest position. 相似文献
199.
Solar System Research - An active region (AR) of the sun is an area of strong magnetic field. Sunspots are frequently formed in an AR. Solar activity exhibits in the form of solar flares and... 相似文献
200.
Parisa Gholami Zadeh Mohammad Hossein Adabi Mohammad Reza Ghassemi Abbas Sadeghi Safar Ali Eshraghi 《Basin Research》2020,32(6):1626-1652
Mélanges are formed by sedimentary, tectonic and diapiric processes and are generally found in collisional belts. The Zagros Orogeny provides an intriguing geological laboratory for the study of mélange-forming processes during the progressive tectonic evolution of the Neotethys Ocean. Different types of tectonic and sedimentary mélanges occur in specific structural positions within the Zagros orogenic belt in the Neyriz Region (Iran). Based on their block-in-matrix fabrics, and tectonostratigraphic positions, we differentiated 14 different mélange types, which mark different episodes of the tectonic evolution of the Neyriz Region from the Cretaceous subduction to the Miocene collision. The Cretaceous subduction stage is recorded by volcanic-sedimentary mélanges (Mv). Sedimentary mélanges characterized by megabreccia from the Cretaceous limestone (Ms1) and Eocene polymictic megabreccia (Ms2) represent epi-nappe mélanges formed during the Palaeocene–Eocene in wedge-top basins. The ophiolite emplacement in the Oligocene resulted in local extensional tectonics in the upper part of the ophiolitic nappe, and deposition of a polymictic megabreccia (Ms3, Ms4). As the final production of the Neotethys Ocean closure and the Eurasian-Arabian collision, the sedimentary mélanges characterized by different types of chaotic rock units (Ms5, Ms6, Ms7 and Ms8 facies) were developed in front of the Cretaceous–Eocene nappes due to growth of the orogenic wedge in the Miocene. Our findings indicate that the recognition and distinction of different types of mélange may provide additional constraints for a better understanding of the tectono-sedimentary evolution of the Neotethyan region. 相似文献