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Dynamic behaviour of ground-supported tanks considering fluid-soil-structure interaction (Case study: southern parts of Tehran) Полный текст
2015
Ghanbari, Ali | Abbasi Maedeh, Pouyan
Regarding the importance of the prevention of hazards and adverse environmental impacts in industrial and populated areas such as southern parts of Tehran city, the response of impulsive period ground-supported tanks were assessed. Having considered the study area's soil properties, the response of ground-supported tanks was modelled. Regarding the soil properties of southern parts of Tehran, the soil structure interaction method explained in FEMA 368 revealed that the interactional impulsive period (~T) was greater than non-interactional one (T). In addition, results showed that Poisson's ratio and stiffness ratio (K/Kx) were more effective regarding the response of the interactional period of ground-supported tank systems. According to the achieved results, the liquid mass density effect on impulsive period was as low as the thickness of the ground-supported walls effect. Results showed that wall materials significantly affected the variation within the impulsive period. Generally, concrete materials were shown to be more periodic than steel materials. Overall, in southern parts of Tehran, when the soil fluid structure interaction method was used, the period increased from 1 to up to 3.6 times greater than the normal impulsive period.
Показать больше [+] Меньше [-]Impact of copper mines and smelter on groundwater quality (Case Study: Rajasthan State in India) Полный текст
2015
Hussain, Ikbal | Hussain, Jakir | Arif, Mohammed | Vadiya, Vinod
Rajasthan is one of the main mineral potential state of India. During the last 30 years it has witnessed enormous expansion of mining industries, but mining of most of the minor minerals coupled with changing climate has posed serious problems to the environmental fabric in the state, apart from base metal beneficiation plants. Groundwater is also being polluted day-by-day by effluents generated from mineral wastes and beneficiation processes in the vicinity of mining sites such as Khetri. Pollutant concentrations were measured in groundwater at the vicinity of Khetri copper mining project, Rajasthan to investigate the influence of copper mining on environment. Pollutant concentrations in groundwater were investigated. Copper metal concentration in water samples were found above the maximum desirable limit in two sources: G4 and G5, due to washing away of mineral with water. Mining industry has deteriorated quality of groundwater resources in the state of Rajasthan, and these industries are becoming centers of pollution sources which need timely actions at government level so that natural resources such as groundwater can be protected.
Показать больше [+] Меньше [-]Remote sensing technology for mapping and monitoring vegetation cover (Case study: Semirom-Isfahan, Iran) Полный текст
2015
Jabbari, Somayyeh | Khajedin, Seyed Jamaledin | Jafari, Reza | Soltani, Saeed
To determine the suitable indices for vegetation cover and production assessment based on the remote sensing data, simultaneous digital data with field data belonging to the spring rangeland of the Semirom-Isfahan province were analyzed. During two years of monitoring the annual, grass, forb, and shrub vegetation cover and the total production data from 86 were collected. The Global Positioning System (GPS) was used to measure the coordinates of plots and transects. Geometric correction and histogram equalization were applied in image processing, and image digital numbers were converted to reflectance numbers. In the next stage, all vegetation indices were calculated from the Advanced Wide Field Sensor (AWiFS) image data and compared with the vegetation cover estimates, at monitoring points, made during field assessments. A linear regression model was used to select suitable vegetation indices. The results showed that there were significant relationships between the satellite data and the vegetative characteristics. Among the indices, the Normalized Difference Vegetation Index (NDVI) consistently showed significant relationships with the vegetation cover. The estimation of the vegetation cover with the NDVI vegetation index was more accurately predicted within rangeland systems. Using the produced model from the NDVI index vegetation crown cover, percentage maps were produced in three class percentages for each image. Generally introduced indices provided accurate quantitative estimation of the parameters. Therefore, it was possible to estimate cover and production as important factors for range monitoring using the AWiFS data. The Remote sensing data and the Geographic Information System are the most effective tools in natural resource management.
Показать больше [+] Меньше [-]Hematological responses of Goldfish (Carassiusauratus) to different acute concentrations of Silver Sulfate as a toxicant Полный текст
2015
Abarghoei, Safoura | Hedayati, Seyed Aliakbar | Ghafari Farsani, Hamed | Gerami, Mohammad Hasan
This study aimed to evaluate the efficacy of silver sulfate (AgSO4) as a toxicant in goldfish (Carassiusauratus). One hundred and forty-seven live specimens of C. auratus were obtained and exposed to 1, 10, 100, 500, 1000 and 2000 ppm of AgSO4for 96 hours. There was one control group (no AgSO4) and three replicates. The physicochemical properties of water and the following parameters were constant: pH: 7.56±0.45 (TS1); temperature: 19±1°C; hardness: 293±2.35 ppm and dissolved oxygen: 8.80 ±0.06 mg L-1 (DO-5510). LC1, LC10, LC30, LC50, LC70, LC90 and LC99 were calculated in 24, 48, 72 and 96 hours. For assessing the impact ofAgSO4 on physiological responses of goldfish hematological indices, blood glucose and cortisol levels were measured. Results showed that LC50 96-h of AgSO4 for goldfish was 687.81 ppm. In addition, the use of AgSO4induces a significant decrease in MCHE after 48 hours, MCV and MCH after 96 hours and lymphocyte after 96 hours in contrast to the control group (P<0.05). Furthermore, increased lymphocyte was significant after 24 hours exposure (P<0.05). In addition, glucose increased significantly at P<0.05 with time increase24 hours after experiment but this (). In conclusion, the study showed that acute toxicity of AgSO4induced hematological alterations in goldfish and offers a tool for the evaluation oftoxicity-derived alterations.
Показать больше [+] Меньше [-]Development of a new low-cost procedure for wind farm maintenance with a view to decrease soil pollution Полный текст
2015
Costa, Angel M. | Fraguela, Feliciano | Orosa, Jos&eacute; A. | Roshan, Gholamreza
The purpose of this article is to present the development of a wind farm, with a condition monitoring system (CMS) based on control charts as the algorithm, centred on a new index, to prevent soil pollution by oil spills in wind farms. To this end, temperature sensors can be considered as one of the more significant sensors to be employed in this study, because the information obtained with regard to anemometers and electrical power output counters can be employed by the control system. As a result, among the other variables, oil temperatures sampled in multipliers used in the wind turbines of a real wind farm were employed. Statistical analyzes were developed and the relationship between wind farm maintenance (usually related to wind farm oil spills) and oil temperature was obtained. Furthermore, a practical case study, centered in the statistical process control, based on the low-cost sample variable was developed and showed that this new procedure would improve deficiencies in the maintenance process, thus, reducing the failure detection time under low sensor cost, as also the related soil pollution.
Показать больше [+] Меньше [-]Natural radioactivity in virgin and agricultural soil and its environmental implications in Sungai Petani, Kedah, Malaysia Полный текст
2015
Ahmad, Nisar | Jaafar, Mohamad | Alsaffar, Mohammed
A study on natural radioactivity in virgin and agricultural soil samples collected from Sungai Petani was conducted using high-purity germanium. The mean activity concentrations of 226Ra, 232Th, and 40K in virgin soils were 51.06±5.83, 78.44±6.42, and 125.66±7.26 Bq kg−1, respectively, while those in agricultural soils were 80.63±5.78, 116.87±7.87, and 200.66±18.24 Bq kg−1, respectively. The corresponding activity concentrations in agricultural soils were higher than those in virgin soils and those reported for other countries of the world. The average values of radium equivalent activity (Raeq), external hazard index (Hex), internal hazard index (Hin), outdoor annual effective doses (Eout), and indoor annual effective doses (Ein) in agricultural soils were 258.38 Ba kg−1, 0.708, 0.925, 0.162 mSv y−1, and 0.669 mSv y−1, respectively. The average values of outdoor external dose (Dout) and indoor absorbed dose (Din) rate in agricultural soils were 116.04 and 218.46 nGy h−1, respectively, which were higher than the permissible limit. Soil with Hex and Hin less than unity are suitable for use as building materials and in agriculture.
Показать больше [+] Меньше [-]Assessment of indoor cancer linked to accumulated radiation dose from different types of television sets in dwellings Полный текст
2015
Njinga, Raymond | Mamman, Sameul
Exposure to radiation from different types of television sets was measured to ascertain the levels of hazards posed to the human biological system. Measurement of the annual radiation dose hazards was performed using a halogen-quenched GM tube with thin mica end window having a density of 1.5 mg/cm2, effective window diameter of 0.360 inch and side wall of 0.012 inch thick. The GM tube was placed for 180 minutes and the sensor faced the screens of the various TV sets, one meter apart. The annual radiation dose ranged from 0.012 ± 0.006 mSv/yr for plasma-SONY to 0.13 ± 0.012 mSv/yr for SHARP and SAMSUNG 24 inch TV sets, containing cathode ray tubes. The annual doses from the 15 and 24 inch-LG TVs (manufactured with cathode ray tubes) were relatively low, with values of 0.031 ± 0.017 and 0.035 ± 0.005 mSv/yr, respectively. The 21 inch THERMOCOOL and PROTECH (with cathode ray tubes), produced annual doses of 0.110 ± 0.052 Sv/yr and 0.063 ± 0.002 mSv/yr, respectively. This provides an insight into the amount of radiation generated by different TV sets in households, on an annual basis. After some years of exposure to TV radiation, health complications such as carcinogenesis or other adverse cellular events may occur, due to cumulated (but does not always) doses which may result in DNA damage, to the human biological system.
Показать больше [+] Меньше [-]Environmental policy and management of freshwater resources in the Haraz-Ghareh Su Basin in comparison to other Caspian sub basins Полный текст
2015
Hedayati Aghmashhadi, Amir | Jafari, Hamidreza | Mehrdadi, Naser | Fahmi, Hedayat | Farshchi, Parvin
Haraz-Ghareh Su is one of the seven sub-basins of the Caspian basin, located on the southern shores of the Caspian Sea, and as such, is in danger of water crisis due to absence of proper systematic policy and strategy. In this study, the pressure factors on the Haraz-Ghareh Su water resources were identified using DPSIR model. Then, the pressure parameters on the freshwater resources in the Caspian Basin were scored and prioritized into two categories: human and non-human criteria and eight sub-criteria with the help of questionnaires (the opinion of 36 specialists in environmental planning and management, as well as the use of FANP). Thereafter, the data layers were processed with the help of IDRISI software, and eventually, the data were overlaid in the ArcGIS and the final plan was made. The findings of the study shows that, among 8 effective sub-criteria on the environmental planning and management of the freshwater resources in the Haraz-Ghareh Su Basin, agricultural water consumption with 0.243 score points and dam-making with 0.039 score points are considered most and least important sub-criteria, respectively. Consequently, after the compilation and scoring of sub-basins of the Caspian basin, it appears that the sub-basin of Haraz-ghare Su with 0.158627 points had the worst situation in terms of the planning and management of freshwater resources in the Caspian basin. In order to decrease the pressure on the freshwater resources in the Haraz-Ghareh Su Basin, the formulation of long-term policy and strategy in this basin seems to be essential.
Показать больше [+] Меньше [-]Evaluation of kinetics and adsorption isotherms for the Elimination of Pb(II) from aqueous solutions using Aloe barbadensis Miller Leaf Powder Полный текст
2015
Malik, R | Lata, Suman | Singhal, Sushila
An adsorbent was developed from matured leaves of the Aloe barbadensis miller plant for removing Pb(II) from aqueous solutions. Adsorption was carried out in a batch process with several different concentrations of Pb(II) by varying amount of adsorbent, pH, agitation time and temperature. The uptake of the metal was initially very fast, but gradually slowed down indicating penetration into the interior of the adsorbent particles. The experimental data closely followed both Langmuir and Freundlich isotherms. A small amount of the adsorbent (1 g/50ml) could remove as much as 86% of Pb(II) in 35 min from a solution of concentration 0.3 mg/50ml at 25°C. The adsorption continuously increased in the pH range of 2.0–5.0, beyond which the adsorption could decrease up to pH 7.0 when the adsorption could not be carried out due to precipitation of the metal. The adsorption was exothermic at ambient temperature and computation of the parameters, ΔH, ΔS and ΔG, which indicated the interactions to be thermodynamically favorable.
Показать больше [+] Меньше [-]Application of AERMOD to local scale diffusion and dispersion modeling of air pollutants from cement factory stacks (Case study: Abyek Cement Factory) Полный текст
2015
Noorpoor, Alireza | Rahman, H. R.
Today, the cement industry is one of the major air polluting industries in the world. Hence, in this study, owing to the importance and role of contaminants from the plant, an appraisal of the emission contributions in addition to other factors have been discussed. There are several reasons behind the importance of modeling air pollutants. First, the assessment of standards for air pollution, and the fact that the measurement points are limited. Furthermore, in all industrial areas, measurement and installation of assessment and monitoring stations are not feasible. The AERMOD model is a dispersion steady state model which is utilized to determine the concentration of various pollutants in different areas from urban and rural, flat and rough, shallow diffusion in height, from standpoint and different shallow sources. In this model, it is assumed that the dispersion of concentration in Stable Boundary Layer (SBL) in two horizontal and vertical directions are similar to that of horizontal within Gaussian convectional boundary layer (CBL). With regard to assessment of the parameters and pollutants of stack outlet, the amount of particulate matter was measured as the most important pollutant in the region. Then, via dispersion and diffusion modeling of pollution (AERMOD) along with environmental measurements, the nature of dispersion of this pollutant in the analysis of the surrounding areas was verified. According to the presented results, the highest level of concentration for particulate matters in all areas affected by cement factory amounts to 43.68 (μg/m3) which occurred at a distance of 1500 m in the east direction and 2100 m in the north direction.
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