Investigating Issues and Problems of Using Sewage Effluent in Agriculture

The ever-increasing growth of the population and the rapid development of industries are important factors that have caused an increase in water consumption and wastewater production in communities. On the other hand, in countries located in arid and semiarid regions, available water resources are limited. Therefore, the use of non-conventional water resources (sewage) in these countries is becoming more important day by day. The use of wastewater as a permanent source of water in agriculture, in addition to providing a part of water needs, also saves and sustains water resources. In this research, the effluent of the wastewater treatment plant of Arak city in the central province of Iran was studied in order to check its quality and usability in agriculture. The quality of the effluent was compared with the standards. The results of the research showed that the above wastewater has no restrictions for use in agriculture according to the investigated parameters. This text is compiled based on the results of various research studies conducted in different parts of the world. Finally, the challenges and opportunities of using wastewater in agriculture and providing suitable solutions to reduce the problems have been discussed

Assessing the Crop Pattern and the Optimized Irrigation Methods Using AHP Method for Municipal Wastewater Usage in Arak, Iran

Nowadays, the problem of water scarcity and wastewater treatment and reuse has made the proper crop cultivation pattern and irrigation method as the most important alternative in developing water resources management and could play a crucial role in meeting the water scarcity issues. The purpose of this study was to evaluate the quality of wastewater from Arak city wastewater treatment plant in order to use in agriculture and to determine the pattern of cultivation and appropriate irrigation method using AHP process. Development of model had two sub-models. The purpose of the first model was to determine optimal crop pattern at the irrigation network level and the purpose of the second model was to select the most appropriate method for irrigation using wastewater.  In this descriptive cross-sectional study, wastewater sampling of the Arak wastewater treatment plant was conducted to determine the quality parameters of effluent and comparing them with the standard values. The mean COD, BOD5 and DO parameters were 49.65, 23.26 and 1.93 mg/l respectively; the mean concentration of cadmium, copper, and lead was 0.0564, 0.08, and 0.0512 mg/l, which compliance with the standards set by Iran Environmental Protection Agency for wastewater reuse in agriculture. Total and fecal coliforms of the effluent were 877.882 and 379.558 per 100 ml. The mean number of parasite eggs was 0.52 per liter; hence, it is not recommended for agricultural irrigation. Therefore, the most limiting factor for determining the cultivation pattern is water and soil electrical conductivity followed by water cost, for which the highest Result showed that apart from total and focal coliforms, there is no limitation for re-use of the effluent in agricultural irrigation. In addition, the most limiting factor was determining the pattern of cultivation, the electrical conductivity of water and soil, followed by the cost of water, which had the highest relative weight percentage. In selecting the best irrigation systems, drip irrigation systems, surface and subsurface drip had the highest relative weight, respectively

Accuracy Estimation of Sediment Discharge Transfer Relationships of Khondab River, Joshirvan Station using HEC-RAS Model

Due to the complexity of hydraulic and sedimentary problems in rivers, it is not possible to solve the equations analytically, so numerical methods are used. In the present study, the HEC-RAS 5.0.3 model was used to simulate the sediment flow of the Khondab River. For this purpose, using the topographic map of the route, DEM and TIN of the River route with a scale of 1: 2000, in the HEC-GeoRAS extension package in ArcMap software, 200 sections along 5 km of the river were prepared. Relevant information was inserted to introduce the river geometry to the model. The flow rate was calculated with 25-, 50- and 100-year return periods and was used for river hydraulic simulation. Quasi-volatile flow conditions, boundary conditions and granulation of riverbed materials were introduced to the model. Using sediment transport estimation relationships, river sediment transport capacity was calculated. The results showed that the Mir-Peter and Müller relationship with 26% error is closer to the observed sediment values ​​than the other relationships. Moreover, the study of erosion and sedimentation status of the river using Hjulstrom and Shields criteria showed that a part of the sections of this river is in erosion status and another part is being sedimenting

Numerical Simulation of the Effect of Weir Magnification on Hydraulic and Hydrodynamic Characteristics in Diversion Dams

Since the geometry of duck tip overflows will complicate the problem for theoretical and practical purposes, it is crucial to study the magnification and hydraulic change of flow on these overflows. In this study, the effect of these changes on the hydraulic and hydrodynamic properties of the flow was investigated by numerical simulation using FLOW3D software by changing the overflow shape from linear to duck tip with magnifications 2 and 3. Dimensional analysis extracted dimensionless ratios and the relationship between variables in the experiments was determined. The results of comparing the numerical model with the laboratory model showed that the maximum error obtained from numerical simulation for the overflow coefficient of overflows is 12%. The permeability coefficient in the linear overflow with magnification 1 first had an increasing trend and then a decreasing trend. From a relative head greater than 0.6, the permeability coefficient was proved to be 0.7 for experimental data and 0.75 for simulation data. In the overflow, with a magnification of 2 to a relative head of 0.4, there was an increasing trend and from a relative head greater than 0.4, there was a decreasing trend. In the overflow with magnification 3, the permeability coefficient always decreases with increasing the relative head

Effectiveness Assessment of Suspended Sediment Load Estimation Methods in the Ghar Chai River

Estimation of sediment load in rivers is one of the most important and applicable issues in studies and design of river and water engineering projects. Therefore, identification and suggestion of suitable methods for estimating suspended sediment load should be done based on relevant research. These methods include artificial neural network models, neurophysics, sedimentation rate curve as well as multivariate regression model. In this study, the efficiency of these methods was investigated in predicting discharge rate of suspended sediments of Gharachai River watershed. Daily time series data of measured flow discharge and sedimentation of bridge station of Gharachai River were used. The statistical period used in this model was two years (2016-2017). Independent variables used to enter the network include runoff and suspended load at the Gharachai River Doab Bridge station. The dependent variable, which is the network output, was the suspended load. After modeling with each compound and calculating RMSE and R2 values, the best combination was selected. The results showed that the neurophasic method based on discharge and sediment inputs and artificial neural network models based on discharge inputs were more accurate than multivariate regression and sedimentation rate curve. For values ​​higher the long-run mean of the statistical series, the values ​​simulated by the ANN model and for values less the mean and annual sediment load were also closer to the observed values. While for maximum values, no significant difference was found between ANN models, neurophysics, and linear regression

Juvenile Churg-Strauss Syndrome as an Etiology of Myocarditis and Ischemic Stroke in Adolescents; a Case Report

Background: Churg-Strauss syndrome (CSS), a systemic vasculitis accompanied by asthma and eosinophilia, almost invariably affects the lung and is frequently associated with cutaneous involvement. It rarely has cardiac involvement. We report an unusual case of CSS with myocardial involvement and stroke. Case Presentation: A 16-year old female suffered of allergic asthma for 4 years. She was under treatment with oral prednisolone and seretide inhalation. After CSS diagnosis, she developed paroxysmal atrial tachycardia. Serum levels of Troponin I and Troponin T were increased indicating massive myocardial damage probably due to myocarditis. After 5 months she developed acute hemiparesis without any evidence of ischemic or hemorrhagic event. She was treated with IVIg, intravenous pulses of methylprednisone and cyclophosphamide for each complication. Conclusion: Myocarditis and stroke may also complicate CSS which should be taken in consideration for better management

Effects of two types of anorganic bovine bone on bone regeneration: a histological and histomorphometric study of rabbit calvaria.

The purpose of this study was to evaluate the efficacy of two types of bone substitutes, Bio-Oss and NuOss, for repair of bone defects.This study was performed on the calvaria of 14 New Zealand rabbits. The 6mm critical size defect (CSD) models of bone regeneration were used. Three CSDs were created in each surgical site. The first defect was filled with NuOss, the second one with Bio-Oss and the third one remained unfilled as the control. After healing periods of one and two months (seven animal for each time point), histological and histomorphometric analyses were carried out to assess the amount of new bone formation, presence of inflammation, foreign body reaction and type of new bone. Qualitative variables were analyzed by multiple comparisons, Wilcoxon, Friedman and Mann Whitney tests. Quantitative variables were analyzed using the Mann-Whitney and Wilcoxon tests. Level of statistical significance was set at 0.05.The level of inflammation was not significantly different at four and eight weeks in the Bio-Oss (P=0.944), NuOss (P=1.000) and control groups (P=0.71). At four weeks, foreign body reaction was not observed in Bio-Oss, NuOss and control groups. There was no significant difference in the type of the newly formed bone at four and eight weeks in any group (P=0.141 for Bio-Oss, P=0.06 for NuOss and P=0.389 for the control group).Deproteinized bovine bone mineral can be used as a scaffold in bone defects to induce bone regeneration

Resonant Light-Induced Heating in Hybrid Cavity-Coupled 2D Transition-Metal Dichalcogenides

Hybrid structures based on integration of two-dimensional (2D) transition-metal dichalcogenides (TMDCs) with optical resonators have recently earned significant attention. The enhanced interaction of light with 2D materials in such hybrid structures can enable devices such as efficient light-emitting diodes and lasers. However, one of the factors affecting the performance of such devices is the effect of the optically induced heat on the optoelectronic properties of the 2D materials. In this study, we systematically investigate principal roots of heat generation in hybrid cavity-coupled few-atomic-layer-thick 2D TMDC films under optical pumping. The optical resonator exploited here is a Fabry–Perot (FP) resonator, which can enhance the light–MoS₂ interaction by a significant factor of 60 at its resonance wavelength. We have combined an accurate theoretical modeling with experimental Raman spectroscopy to determine the roots of heat generation in MoS₂ films integrated with FP resonators. Our investigations reveal that the strong modulation of light absorption in the MoS₂ film, induced by excitation of an FP cavity at its resonant frequency, plays the primary role in excess heat generation in 2D materials. Furthermore, through varying the cavity length, we show that on-resonance and off-resonance excitation of the cavity results in completely different temperature profiles in the cavity-coupled MoS₂ films. Also, by changing the resonance medium of the FP cavity (SiO₂ and air), we take into account the role of the heat sinking effect of the substrate in heat generation in MoS₂ films. In this study, the temperature-dependent red-shift of the Raman spectra is employed to monitor the local temperature of the MoS₂ films. Our results show the importance of the heating effect in such hybrid structures and represent a step forward for the design of practical hybrid optical devices based on layered semiconducting 2D materials

Proceedings Of The 23Rd Paediatric Rheumatology European Society Congress: Part Two

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