Showing 15 results for Esmaili
Gholam Hossein Tahmasebi, Rahim Ebadi, Morteza Esmaili, Jafar Kambousia,
Volume 2, Issue 1 (spring 1998)
Abstract
The first step in fundamental breeding of any living organism is the determination of its genetic make-up. To investigate the genetic make-up of the European honeybee (Apis mellifera L.) in Iran, some research attempts were made during the years 1992-1996 in which the bee's relationship with some exotic races were determined through the application of morphological methods. For this purpose 13000 samples of worker bees from 1320 colonies of 212 apiaries in 104 cities at 25 provinces were taken and twelve morphological characters were measured by using the international method (Ruttner, 1978). Furthermore, seven morphological characters of 900 drone samples taken from 403 colonies of 111 apiaries in 42 cities at 10 provinces were studied through the same method. The principle component analysis (PCA) was used for statistical analysis of the data obtained. The results indicated that the existing populations of honeybees under study were of the Iranian honeybee race (Apis mellifera meda) which were completely distinguishable from those of imported races such as A.m. carnica, A.m. ligustica, A.m. caucasica and exotic races such as A.m. anatoliaca, A.m. syriaca A.m. yemenitica and A.m. lamarkii. The imported races had not had great genetic impact on the Iranian race, as the Iranian honeybees have had good consistency and stability. In addition, import of the exotic queens has been ceased in the last decade.
A. Ghane, M. R. Ahmadi, A. Esmaili, A. Mirzajani,
Volume 10, Issue 1 (spring 2006)
Abstract
Present study investigates macrobenthic invertebrates and their community structure in Chafrood river to classify and assess the study sites regarding the environmental anthropogenic factors. Along a 9 km distance, 8 study sites were selected, and macrobenthic were monthly sampled using a surber sampler (1600cm2, 250 μ mesh net) with 3 replicate at each station. Collected samples organisms were fixed with 4% formalin and laboratory process including sorting, identification and enumeration of the animals were preceded. During the study 73 benthic taxa were identified which were dominated with aquatic insects larvae especially orders Diptera and Ephemeroptera. The maximum and minimum total abundance was 2335 ind.m-2 in station #2 and 1639 ind.m-2 in station #4 respectively. Benthic animals' frequency data were summarized to community structure metrics including total richness, EPT richness and ratio of EPT frequency to Chironomidae family. A Shannon- Winner diversity index and Hilsenhoff family level biotic index was also determined for each studied station. Result of cluster analysis for stations, based on the community structure metrics and diversity index, was in accordance with the station classification using biotic index and both classify the affected stations at the same group.
A. Esmaili Nameghi, A. Hassanli,
Volume 11, Issue 1 (spring 2007)
Abstract
One of the simple methods for erosion control, flood mitigation and flood damage reduction in the streams is building the checkdams. The present study was carried out to evaluate the performance of checkdams, location across the streams in the retention of the fine sediments in Droudzan watershed in Southern Iran. For this purpose, a number of streams with many stabilized check dams which were more than 27 years old were selected. For each stream, three check dams (one at the far beginning (upstream), the second one at the middle and the third one at the far downstream) were selected. In each stream, a number of samples were taken from retained sediment behind the selected check dams and also original soil was taken from both sides of the same check dams. Laboratory analysis on the size of particles and also texture of soil and sediment samples showed that in general, soils taken from both sides of the check dams were finer than sediment behind the same check dams. Comparison of particle sizes showed in all streams except Joobkhaleh (with extensive tree coverage) the performance of the third check dams (far downstream) in fine sediment retention is much better than the second one (at the middle) and the second one is more effective than the first one (upstream). Comparison of sands, silt, and clay percentage of soil and sediment also showed that in all streams except Joobkhaleh the clay and silt percentage behind the third check dam is more than the second check dam and that of the second check dam is more than the third one (upstream). In the same way, results showed that the sand retained behind the first check dam, was more than the sand behind the second and first checkdams, respectively. Therefore, if the retention of the fine sediments is the main purpose of the check dam construction, it is recommended that they be built in the far downstream rather than in the upstream of waterways.
M Karimpour, M Afyuni, A Esmaili Sari,
Volume 14, Issue 52 (sumer 2010)
Abstract
Sewage sludge application on farmland as fertilizer is commonly practiced in many countries. However, high concentration of heavy metals like mercury (Hg) in sludge can cause pollution of soil, plant and the human food chain. In order to examine the risk of Hg transfer into plants a five year field experiment was conducted in which we investigated uptake of Hg from a sludge-amended soil by corn. Sludge application rates were 0, 25, 50 and 100 Mg ha-1. To study cumulative and residual effects of the sewage sludge, applications were repeated on 4/5 of each plot in second year, on 3/5 of plots in third year, on 2/5 of plots in fourth year and in 1/5 of plots in fifth year. After the fifth year, soil samples from the 0-20 and 20-40 cm depths were taken and analyzed for total Hg. Corn plants were harvested and roots, stems and grains were separately analyzed for Hg concentrations. Sludge application significantly increased total Hg concentration in soil. Total Hg concentration in soil ranged from 20 µg kg-1 (in control plots) to 1200 µg kg-1 (in plots with 500 Mg ha-1 sludge application). Sludge application significantly increased uptake of Hg in different plant parts. At the end of the fifth year the average Hg concentrations in root, stem, and grain were 91, 9, and 8 µg kg-1, respectively. Corn yield increased significantly with sludge application and this fertilizer effect was visible five years after a single sludge application.
M. Khastar-Borujeni, H. Samadi, K. Esmaili,
Volume 18, Issue 68 (summer 2014)
Abstract
Due to adhesion properties of fine sediments, chemical physics factors of fluid can cause changes in the behavior of sediments. In this study, the characteristics of sediment deposition with three levels of waste water, different shear stresses and initial sediment concentrations were investigated in the annular flume located at Hydraulic Laboratory of Shahrekord University. Sediments for experiments were taken from the Pirbalut dam reservoir. The velocity and the shear stress profiles were measured using an Acoustic Doppler Velocimeter (ADV).The results showed that the concentration of cohesive sediment was decreased with time and finally it reached an equilibrium concentration of sediment. The equilibrium concentrations to initial concentration (Ceq/C0) in special shear stress, for different initial sediment concentrations and different levels of waste water were almost the same. Equilibrium concentration was dependent on the initial concentration sediment. Threshold and full deposition shear stresses were increased in waste water. Shear stresses of full deposition for 0, 30 and 60 % wastewater were 0.053, 0.075 and 0.070 N/m2, respectively. Also, for specified levels of waste water, the values
were obtained 10, 15 and 17, in which the suspended sediments would remain.
A. Esmaili Dastjerdipour, M. H. Farpoor, M. Sarcheshmehpour,
Volume 18, Issue 69 (fall 2014)
Abstract
Organic substances produced by cyanobacteria and some polymeric compounds play a role in soil aggregation and increase soil structure stability in sandy soils. Effects of biological soil crusts and some polymeric compounds on some properties of a sandy soil were investigated in this research. Inoculation of three cyanobacterial treatments (Nostoc sp., Phormidium sp. and their combination) and four time intervals on crust formation, organic carbon and calcium carbonate contents, resistance to penetration and MWDD in soils below the crusts were studied in the first experiment. Combination of two cyanobacterial species in 60 days treatment with 2.2 % organic carbon, 0.2 Mpa resistance to penetration, and 96.7 % large aggregates was introduced as the superior treatment. Effect of superior cyanobacteria and time treatments on aggregate size distribution was studied in the second part of this experiment. Sixty-day treatment with 96.7 % of large aggregates was the most effective treatment. Structural stability of a sandy soil influenced by four concentration levels (0, 1, 2 and 4%) of anionic polyelectrolyte polymer at the depths of 1, 2 and 3 cm was investigated in the second experiment. Four percent concentration treatment of polymer with 0.6 Mpa resistance to penetration and 90.9 % large aggregates was the most effective one. A significant difference in resistance to penetration among three depth intervals was also observed
Seyyed S. M. A. Maddahzadeh., K, Esmaili, B. Ghahraman,
Volume 21, Issue 1 (Spring 2017)
Abstract
Bi-level drainage system is a type of underground drainage systems, in which adjacent drainage lines are installed at different depths. In the Hydraulics Laboratory, Ferdowsi University of Mashhad, a model was built, that include a cube tank 2 meters in length, width and height of 1 meters was made of galvanized. In this model, two rows 20 cm apart from each other drains were installed. As drainage, a pipe of three layers to the outer diameter of 16 mm was made of PVC. Within this model of stratified soil was used as a soil layer of low permeability with a hydraulic conductivity of 1.15 cm per hour, thickness of 20 cm soil layer between two light soil layer with 30-cm thickness for bottom layer and 20 cm for the top layer with a hydraulic conductivity of 1.55 cm per hour. For accurate measurement of the water table Behavior in the soil at each point of the model, some piezometer distance of 10 cm from each other on the floor model was installed. After Outfit of model with blow-off valve, Experiments with a heavy irrigation for different intervals between depths of 30 and 50 cm were used in drainage and water table elevation values as observed values were extracted from the model. The results show that the values obtained from Upadhyaya and Chauhan Equation only in small area of water table profiles, which include an area of between the two drainage, are consistent with observed and with a wider distance between deep and shallow drainage, time of drop in water table increased.
S. Esmailian, A. Talebi, M. Esmailian,
Volume 22, Issue 1 (Spring 2018)
Abstract
This research was aimed to simulate and prioritize the effective factors on water erosion using USLE-M in the system dynamic model. In this integrated model, by using the system dynamic simulation software (Vensim), all variables and factors involved in erosion and soil loss were considered according to the USLE-M model. After model implementation, the estimated values and observations were compared and then sensitivity analysis was done to determine the sensitive parameters. Then, calibration was performed on the sensitive parameters. This study found that that the results of the model were acceptable for soil erosion simulation due to considering all the effective factors in soil erosion. The results of the sensitivity analysis also indicated high model sensitivity to the slope and vegetation cover in high and low slopes, respectively. By investigating the changes in various parameters such as vegetation cover and slope on erosion, the optimal vegetation cover with 67 and 40% slope, was estimated to be 20 and 60%, respectively.
K. Esmaili, S. Seifi, H. Salari,
Volume 22, Issue 3 (Fall 2018)
Abstract
Settling basins are one of the most essential structures for the separation of inflow sediments. This structure is established to enhance the water quality after the river-basins and water channels. Numerous studies have been conducted on the design of this structure and different methods have been provided to increase its efficiency. However, the use of simple settling basins with the minimum cost which can provide the ideal targets has been the focus of designers. In this study, the effect of flow-guiding plates and the angle between these and the inflow, and the impact of water depth in the basin on the trap efficiency of the settling basins were considered. For testing, 4 blades with specific length and angle were installed. This experiment was repeated for 3 different lengths and 3 angles. The results of the experiments showed that with the enhancement of the depth of water to 10 centimeters to 30 centimeters, while the basin had no flow-guiding plates, increased the trap efficiency of the basin by 4.9 percent. Also, by the use of flow-guiding plates in the suitable and best length and angle (in this study, the suitable size of blades was 22.5 centimeters and the best position was by the angle of 30 degrees); with the maximum of the water depth of 30 centimeters, the trap efficiency was increased by 13.3 percent. The sensitivity analysis done showed that the depth of water had the most effect on the trap efficiency of the basin and the changes in the lengths and angles of the blades position had the similar effects of the basin trap efficiency.
S. Salehi, Sh. Esmael Zade, Gh. Panahi, K. Esmaili,
Volume 22, Issue 4 (Winter 2019)
Abstract
The effect of the uplift force in the hydraulics structures is against stability. So, determining and controlling this force can be very important. One of the ways to achieve this purpose is to decrease this force by using the hole drains; in this way, we can build perpendicular pipes with different diameters, leading to the durability of the structure. Therefore, an experimental model of concrete dam was constructed in the hydraulic laboratory. The dam's model was divided into five sections by using 4-hole drains with a thickness equal to the dam's foundation. By running experiments with the maximum water level at the upstream, dam hole drains were opened in their position. Hydraulic potential was estimated by using the Piezometer built in the flume body. Finally, by opening some hole drains, the uplift force was calculated from the equipotential lines. Therefore, the best case (which had the minimum force) was determined, which was a/L=0.4, to create the most proper hole drain in the dam foundation. (a: distance of drain to heel and L: length of the dam's foundation). To place the hole drain in this position, by applying the zero potential in this position, the up lift force was increased
A. Arab, K. Esmaili,
Volume 25, Issue 1 (Spring 2021)
Abstract
The study of floods has always been important for researchers due to the great loss of life and property. Investigation of flood bed can provide appropriate solutions to reduce this phenomenon to managers and researchers. In this research, the compound channel (with flood plain on one side of the main channel) Been paid, Therefore, two experimental models of compound channel in laboratory flume were examined by considering dimensional analysis. With the goal Investigation of lateral slope of flood wall in laboratory model In the first model, transverse slope 0 And in the second model, a value equal to 50% Was considered. Also in order to investigate the effect of longitudinal slope of river bed sediments Longitudinal slope in three steps 0.00 2, 0.004 and 0.006 Was changed. Examining the ADV speedometer data, the results showed that with increasing the longitudinal and transverse slope (slope of the flood wall) of the channel, the maximum longitudinal velocity changes to the floor of the channel. In order to investigate the effect of average sediment diameter on the scouring process during experiments Mm was used. The results showed that increasing the longitudinal and transverse slope had a great effect on increasing the volume of washed sediments 3 and 0.9 of sandy sediments with a diameter Along the canal and with the increase of these longitudinal and transverse slopes in the channel, more sediment transport volume occurs. In the following, using Investigation of dimensionless numbers obtained from dimensional analysis, dimensionless weight landing number was introduced to evaluate this value value of other hydraulic parameters and Was introduced. A relationship based on nonlinear regression with correlation coefficient Acceptable was introduced at around 0.88.
S. Salehi, A.r Esmaili, K. Esmaili,
Volume 25, Issue 4 (Winiter 2022)
Abstract
The objective of this study was to investigate how the earth dam is destroyed due to the effect of upstream and downstream slope of the body in overflow conditions. Therefore, eight models were provided that each model is constructed from the embankment dam with different upstream and downstream slopes (1:1, 2:1) and the soil properties (Sc) on breach formation. The time and method of dam break for flood discharges were investigated. The results showed that the upstream side slope of the embankment dam has less effect than the downstream side slope on the scour process resulting from the phenomenon and by increasing the downstream side slope of the embankment dam, the amount of erosion in the scour hole increases 28 %. Then, using nonlinear regression, relationships were presented to estimate the output flow rate and the location of the waterfall. A to the erosion and formation of the waterfall inside the body of sticky earth dams, two main outlines of the great waterfall and a series of waterfalls were presented. Finally, the formation of these waterfalls due to the effect of shear stress created during sediment erosion relative to the critical shear stress of the dam constituents was investigated and evaluated. Considering the limitations based on shear stress, the formation status of the type and the leaching pattern of the body of the cohesive earth dams during the overpass were estimated. Then, a general plan was presented to predict the behavior of the overflow stream in homogeneous and sticky soil.
S.a.r Esmaili, A. Mosaedi,
Volume 26, Issue 1 (Spring 2022)
Abstract
In recent decades, population growth, urban sprawl, urban environmental changes, and related issues are one of the significant issues in proper planning to manage the urban environment. One of the issues in urban development is the occurrence of floods and flooding due to heavy rains. In this research, flood modeling was studied in Mashhad Zarkash watercourses. The amount of rainfall for the return period of 10, 25, 50, 100, and 200 years were extracted by CumFreq software using the maximum 24-hour rainfall statistics of three rain gauge stations closer to the Zarkesh, Jagharq, Sar-e-Asyab, and Torqabeh watercourses basins during the statistical years 1364 to 1390. The peak discharge was calculated using the US Soil Protection Organization (SCS) rainfall-runoff method. Zarkesh watercourse is located on the outskirts of Mashhad. River and flood flow modeling was performed using Arc GIS, HEC-GEORAS, and HEC-RAS software in two conditions including structure (bridge) and no structure. Due to urban marginalization, urban development and land use change have greatly expanded in this region. The results of flood simulation showed that flood levels with a return period of 50 years increased by 50000 m2 equal to 22% in the presence of a structure compared to the state without a structure. The results of this research show that the construction of bridges on the river, the roughness coefficient by land use change, and the number of curves due to land permeability changes are effective in the flood zone.
S. Esmailian, M. Pajouhesh, N. Gharahi, Kh. Abdollahi,
Volume 27, Issue 3 (Fall 2023)
Abstract
Awareness of the number of changes in runoff and sediment on different slopes can be useful in modeling the production of runoff and sediment. Therefore, this study was conducted to investigate the production of surface and tunnel runoff and sediment in saline and sodic soils on different slopes. Saline-sodic soil was collected and transported to the laboratory. Laboratory experiments were performed on a soil bed in a rectangular flume at three different slopes (5%, 10%, and 15%) under simulated rain (30 mm/h) for one hour. An analysis of variance was used to investigate the effect of slope on runoff and sediment production, and the means were compared using Duncan's test at the five percent level using SPSS version 26 software. The results showed that there was a significant difference between the slopes of the runoff (P<0.001) and sediment (P<0.001). In the first minute of the experiments, due to the lack of moisture in the soil, the amount of runoff was low, but over time, the amount of runoff increased. It is because the pores are blocked by the dispersion of soil particles owing to the presence of sodium ions, which ultimately leads to a decrease in permeability. Similarly, in the last few minutes, outflow from the tunnel was observed, and this flow occurred only on slopes of 10% and 15%. The amount of sediment was also low in the first few minutes, which could be related to the low amount of runoff and the lack of sediment particle removal. Nonetheless, after the lapse of time, its amount increased, and the primary reasons were reduced permeability, increased runoff, and removal of fine particles from the soil surface.
S. Esmailian, M. Pajouhesh, N. Gharahi, Kh. Abdollahi, Gh. Shams,
Volume 28, Issue 2 (Summer 2024)
Abstract
Studying the process of soil erosion and evaluating its effective factors is one of the most important prerequisites for proper management of soil and water resources. This study was conducted to investigate the production of surface and pipe runoff and sediment using artificial rainfall on silt loam soil in the laboratory. So, the soil was collected from the study area and transported to the laboratory. Laboratory experiments were performed on a soil bed in a rectangular flume with three pipes, at slopes of 2%, 6%, 10%, 14%, and 18% under simulated rain (30 mm/h) for one hour. Related graphs were drawn in Excel to analyze the results, and Spearman's correlation test was used in SPSS software to check the correlation between runoff and sediment values in each slope. The results showed that with the increase in slope, the sum of surface and pipe runoff and sediment increased over time. For example, in a slope of 2%, the runoff and sediment in the initial moments of the experiment increased from 0 to 1.3 liters and 26.2 g m-2 at the end of the experiment. Also, the correlation coefficient between runoff and sediment in the slopes was 0.98, 0.62, 0.4, 0.93, and 0.15, respectively, which was significant in some, but in others, it was not significant because of soil loss.
