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21.
Torkashvand Javad Rezaei Kalantary Roshanak Heidari Neda Kazemi Zohre Kazemi Zahra Farzadkia Mahdi Amoohadi Vida Oshidari Yasaman 《Environmental science and pollution research international》2021,28(35):47741-47751
Environmental Science and Pollution Research - Landfilling is known to be the most widely used method in municipal solid waste management in many countries. Landfill leachate containing different... 相似文献
22.
Susan J. Colarullo Manoutchehr Heidari Thomas Maddock III 《Journal of the American Water Resources Association》1984,20(5):747-760
A groundwater hydraulic management model is used to identify the optimal strategy for allocating limited fresh-water supplies and containing wastes in a hypothetical aquifer affected by brine contamination from surface disposal ponds. The present cost of pumping from a network of potential supply and interception wells is minimized over a five-year planning period, subject to a set of hydraulic, institutional, and legal constraints. Hydraulic constraints are formulated using linear systems theory to describe drawdown and velocity variables as linear functions of supply and interception well discharge decision variables. Successful validation of the optimal management strategy suggests that the model formulation can feasibly be applied to define management options for locally contaminated aquifer systems which are used to fulfill fresh-water demands. 相似文献
23.
Manoutchehr Heidari 《Journal of the American Water Resources Association》1982,18(6):1003-1012
ABSTRACT: A ground water management model based on the linear systems theory and the use of linear programming is formulated and solved. The model maximizes the total amount of pound water that can be pumped from the system subject to the physical capability of the system and institutional constraints. The results are compared With analytical and numerical solutions. Then, this model is applied to the Pawnee Valley area of south-central Kansas. The results of this application support the previous studies about the future ground water resources of the Valley. These results provide a guide for the ground water resources management of the area over the next ten years. 相似文献
24.
Tahereh Gholami Mahdi Akbarzadeh Majid Motamedzade Rashid Heidari Moghaddam 《International journal of occupational safety and ergonomics》2016,22(2):283-290
This study examined the hypothesis that burnout syndrome mediates effects of psychosocial risk factors and intensity of musculoskeletal disorders (MSDs) among hospital nurses. The sample was composed of 415 nurses from various wards across five hospitals of Iran's Hamedan University of Medical Sciences. Data were collected through three questionnaires: job content questionnaire, Maslach burnout inventory and visual analogue scale. Results of structural equation modeling with a mediating effect showed that psychosocial risk factors were significantly related to changes in burnout, which in turn affects intensity of MSDs. 相似文献
25.
Manoutchehr Heidari Kamran Ghiassi Edward Mehnert 《Journal of the American Water Resources Association》1999,35(2):333-347
ABSTRACT: The nonlinear least squares (NLS) method was applied to pumping and recovery aquifer test data in confined and unconfined aquifers with finite diameter and partially penetrating pumping wells, and with partially penetrating piezometers or observation wells. It was demonstrated that noiseless and moderately noisy drawdown data from observation points located less than two saturated thicknesses of the aquifer from the pumping well produced an exact or acceptable set of parameters when the diameter of the pumping well was included in the analysis. The accuracy of the estimated parameters, particularly that of specific storage, decreased with increases in the noise level in the observed drawdown data. With consideration of the well radii, the noiseless drawdown data from the pumping well in an unconfined aquifer produced good estimates of horizontal and vertical hydraulic conductivities and specific yield, but the estimated specific storage was unacceptable. When noisy data from the pumping well were used, an acceptable set of parameters was not obtained. Further experiments with noisy drawdown data in an unconfined aquifer revealed that when the well diameter was included in the analysis, hydraulic conductivity, specific yield and vertical hydraulic conductivity may be estimated rather effectively from piezometers located over a range of distances from the pumping well. Estimation of specific storage became less reliable for piezometers located at distances greater than the initial saturated thickness of the aquifer. Application of the NLS to field pumping and recovery data from a confined aquifer showed that the estimated parameters from the two tests were in good agreement only when the well diameter was included in the analysis. Without consideration of well radii, the estimated values of hydraulic conductivity from the pumping and recovery tests were off by a factor of four. 相似文献
26.
ABSTRACT: Reliable and consistent estimation of the components of the hydraulic conductivity tensor provides information needed to make proper decisions regarding clean up and restoration of contaminated aquifers. In this study, the nonlinear least-squares estimation technique was applied to drawdown versus time data from three or more observation wells to determine a theoretical ellipse of equal drawdown. The angle of rotation of this ellipse with respect to the working coordinate axes was determined by a procedure based on contouring the drawdowns at a given time. This ellipse, in turn, was used to estimate the directions and magnitudes of the horizontal components of the hydraulic conductivity tensor. The technique is applicable to confined, as well as leaky, aquifers. Sources of error in this technique include nonhomogeneity of the aquifer and partial penetration of the pumping and observation wells into the aquifer. The procedure presented may be used as an additional tool to verify computations of hydraulic conductivity anisotropy based on other techniques. 相似文献
27.
Heidari Serve Mostafaei Shayan Razazian Nazanin Rajati Mojgan Saeedi Anahita Rajati Fatemeh 《Environmental science and pollution research international》2021,28(32):43064-43073
Environmental Science and Pollution Research - Lead exposure as a toxic material especially in children can be recognized as a harmful factor for cognitive function system. This meta-analysis was... 相似文献
28.
Hamid-Reza Heidari Farideh Golbabaei Mahmoud Alimohammadi Abbas Rahimi-Froushani 《International journal of occupational safety and ergonomics》2013,19(4):395-405
This study describes optimization of headspace solid phase microextraction followed by gas chromatography equipped with a flame ionization detector for toluene at trace level in spiked urine. The parameters affecting the extraction and gas chromatographic determination of analytes were studied: extraction time and temperature; desorption time and temperature; addition of NaCl; and pH, volume and agitation of the sample. Optimized headspace extraction was carried out at 30 °C for 6 min in the presence of 0.2 g-m-1of NaCl in the sample solution. Also, sample volume and sample pH were optimized at 5 ml and 7 (neutral pH), respectively. Desorption of the analytes was carried out at 250 °C for 60 s. The optimized procedure was validated with 3 different pools of spiked urine; it showed good reproducibility over 6 consecutive days and 6 within-day experiments. The study also determined the accuracy, linearity and detection limits of this method. 相似文献
29.
Ava Heidari Mahdi Kolahi Narges Behravesh Mona Ghorbanyon Fatemeh Ehsanmansh Nogol Hashemolhosini Fahimeh Zanganeh 《Journal of Material Cycles and Waste Management》2018,20(4):2041-2053
The present study aims to develop the Theory of Planned Behavior (TPB) to explain comprehensively the establishment of intention and behavior toward source separation of waste. The extended TPB involves the significant structures affecting the behavior along with the original variables of TPB model. Data were gathered from 420 students in Ferdowsi University, Iran, using questionnaires, and analyzed by cluster analysis, discriminant analysis and structural equation modelling techniques (SEM). The cluster analysis identified three distinct grouping according to TPB constructs, and it was validated by discriminant analysis. SEM results displays that motivation had the most important impact on intention, followed by moral obligation, perceived behavior control, subjective norm, situational factor and attitude. Fit statistic of the extended TPB model was good and had better explanatory power compared to the original TPB. It describes 81 and 57% of the variance for intention and behavior toward source separation waste, respectively. 相似文献
30.
Iftekhar Sidra Heidari Golnaz Amanat Neda Zare Ehsan Nazarzadeh Asif Muhammad Bilal Hassanpour Mahnaz Lehto Vesa Pekka Sillanpaa Mika 《Environmental Chemistry Letters》2022,20(6):3697-3746
Environmental Chemistry Letters - The demand for valuable metals such as rare earth elements and platinum group metals is rising fast in the context of the depletion of natural resources... 相似文献