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Estrous Cycle and Early Pregnancy of White Mice Exposed to Methomyl
2019
Toledo, J. M. | Gamalo, L. E. | Maligalig, M. D. | Suetos, K. J. | Galapon, M.
Methomyl is an oxime carbamate pesticide that is widely used in the Philippines. This insecticide is known to be an endocrine disrupting chemical and a potent genotoxic in mammalian cells. However, limited studies were conducted specifically on its direct effects on estrous cycle and its teratogenic effect. This study aimed to (a) assess the effect of methomyl on the body weight and on the estrous cycle of mice, and; (b) examine the teratogenic effect of methomyl on the progeny of the female albino mice. Five week-old experimental mice in three treatment setups were used in the study for both independent experiments. The treatment schedule for pregnant mice was administered during organogenesis (day 6 to 15 of gestation). Results showed that the average gained weight of the mice of both high dose (HD) and low dose (LD) groups were lower as compared to the average gained weight of the control group but did not show any statistical significant differences (p=0.562). For the experiment 1, methomyl significantly (p=0.013) affect the estrous cycle of the mouse especially in LD group. For experiment 2, results revealed that there was a significant difference among the treatment set-ups (p=0.0001) in terms of fetal morphometric measurement. Furthermore, abnormality and high number of resorption was also observed in both LD and HD treatment groups. Therefore, methomyl significantly affect the body weight, estrous cycle and fetal morphometry. This further confirm that methomyl is an endocrine disrupting and genotoxic chemical that affects the estrous cycle and causes teratogenic effect.
Показать больше [+] Меньше [-]Assessment of Contamination Potential of Leachate from Municipal Solid Waste Landfill Sites for Metropolitan Cities in India
2019
B. P., Naveen | R. K., Malik
With increased population, rapid industrialization and life style changes, the characteristics and the rates of solid waste generation have gone under drastic change in India. Generally, in India, management of solid waste landfill is of major concern with respect to the existing circumstances. The illegal dumping of municipal solid waste on the outskirts of cities is creating major environmental and public health problems. Improper and unscientific waste management results in potential threats from leachate leakage with subsequent impact on environment (i.e. soil, air and waterbodies) and human being. It is therefore, important to evaluate the contamination potential threat of landfill leachate. This study assesses the potential contamination from the landfill leachate by an index called leachate pollution index (LPI) and suggestions are given the landfill sites of five major cities i.e. Bangalore, Chennai, Delhi, Navi Mumbai & Kolkata in India. The landfill leachate samples from these sites have been assessed using leachate pollution index for the implementation of appropriate leachate treatment techniques for reducing the adverse effects on the environment. The results show that the Pallikkaranai landfill site for Chennai city and Mavallipura landfill site for Bangalore city are highly deteriorating and may lead to increase in human health risk for nearby dwellings.
Показать больше [+] Меньше [-]Efficient Removal of Methylene Blue from Aqueous Solution by Adsorption on Cerium Vanadate Nanoparticles
2019
Dehghan Abkenar, Sh. | Hosseini, M. | Sadeghpour Karimi, M. | Ganjali, M. R.
Cerium vanadate nanoparticles (CVNPs) were used as a solid phase adsorbent for removing methylene blue (MB) from aqueous media. The nanoparticles were obtained through a direct precipitation procedure in aqueous solutions, and were characterized by X-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM). The results proved the product to comprise 25-45 nm particles. Batch adsorption experiments to determine the optimal adsorption conditions and the different factors which influence the adsorption efficiency (i.e. pH, amount of CVNPs, contact time, and the concentration of MB) were also evaluated. The experimental data were analyzed using the Langmuir and freundlich adsorption models.The data were satisfactorily fitted to the Langmuir model and a maximum adsorption capacity of 181.8 mg/g was obtained at pH of 3.0. Further kinetics studies were performed on the parameters. The adsorption of the model dye (MB) was found to reach equilibrium after 10 min, following a pseudo-second-order kinetic model. Desorption of the dye and recycling potential of the adsorbent was also studied.
Показать больше [+] Меньше [-]Assessment of Converter Sludge from Esfahan Steel Company as a Persulfate Nano-Activator for Permeable Reactive Barriers (Prbs) in Landfill Leachate Treatment
2019
Soubh, A. M. | Abdoli, M. A. | Baghdadi, M. | Aminzadeh, B.
The present research studies the performance of Converter Sludge (CL)as a nano-activator of persulfate (PS) in Permeable Reactive Barrier (PRB) as an in-situ technology for leachate treatment.In batch experiments, the acidic conditions (pH = 3) have been the most suitable for removal operations, where COD and NH3 removal efficiencies are 69.15% and 60.96%, respectively. The Box–Behnken design (BBD) has been employed to optimize three parameters, namely PS/ COD ratio, CS dose, and pore volume (PV), using COD and NH3 of leachate landfill as the target pollutant. The BBD is considered a satisfactory model to optimize the process. Under optimal conditions (PS/COD ratio: 3.47, CS dose: 3.09 g L-1,and PV: 4.27), the measured values of the COD and NH3 removal efficiencies have been 74.2 and 66.8, respectively, all within the 95%-prediction intervals, which indicate the model’s success in predicting removal values. The biodegradability (BOD5/COD) of the real leachate has been enhanced from 0.25 to 0.77, with the toxicity of real leachate getting decreased by more than 90%.
Показать больше [+] Меньше [-]A Multi-Metric Index for Hydrocarbons Source Apportionment
2019
Mahmudi, M. | Hashemi, S. H. | Salemi, A.
Several studies have been conducted to develop more accurate and precise indices for hydrocarbons source apportionment. The present study, however, develops a new multi-metric index for hydrocarbons source apportionment. It measures Poly Aromatic Hydrocarbons (PAHs) concentration at six stations with well known petrogenic origin, calculating Phe/An, Flu/Py, Chr/BaA, BaA/Chr, An/(An+Ph), Flu/(Flu+Pyr), and IP/(IP+Bghi) indices. All the indices could correctly determine the source of hydrocarbons, except for IP/(IP+Bghi). Subsequently, it uses principle component analysis method to create a combined multi-metric index, based on PAHs, the concentration of which also contributes to the evaluation of new index performance in stations with known origins. Results show that the new multi-metric index can determine the source of hydrocarbons with greater certainty. Then, using this index, the potential source of contamination in the area has been divided into six sections, namely HPY, MPY, LPY, MPE, HPE, and LPE, which indicate origin of high, moderate, and low risk of petrogenic contamination, as well as source of pyrolytic contamination with high, moderate, and low probabilities.
Показать больше [+] Меньше [-]The Study of CO Symptoms' Impacts on Individuals, Using GIS and Agent-based Modeling (ABM)
2019
jalali, S. H. | vafaeinejad, A. R. | aghamohammadi, H. | Esmaeili Bidhendi, M.
The purpose of this study is to use both agent-based modeling as a new method in modeling dynamic phenomena and GIS to show the effects of carbon monoxide (CO) on individuals in the city of Tehran. After collecting the latest information about the severity of carbon monoxide pollutants on different days, one of the days with a very high severity of this pollutant has been selected for investigation and the interpolation map of its data has been developed via IDW method in ArcGIS software environment, which is then re-classified with the NetLogo software environment used to run the agent-based model. At this stage, the agents are randomly produced in four different age groups in the environment and begin moving with the onset of the running process in the environment. Also, the symptoms, caused by the pollution effects on the agents, appear in form of changes in color and are based on carboxyhemoglobin (COHb) levels (percentage) of each. The results indicate that among the considered older age groups, the members of the age group above 65, have had been mostly affected by pollution and the effect of pollution on the agents of the age group of 13 to 30 years old has been less than the other groups.
Показать больше [+] Меньше [-]Application of Hybrid Cells in Series Model in the Pollution Transport through Layered Material
2019
Chabokpour, J.
The present paper aims at investigating the applicability of hybrid cells in the series model for pollution transport inside the layered porous media. For this purpose, four layers of rock material have fallen inside the experimental flume, with eight sensors installed longitudinally inside the media to obtain experimental BTCs. In order to measure time parameters of the model, named , two different methods of LSCF and MM have been examined. The model's sensitivity as well as its temporal equations with different parameters have been assessed. Finally, results show that at the fixed time step, the model is more sensitive to parameter (advection zone time parameter) rather than residential time parameters, to which the moment relations are more sensitive. A detailed computation of the related transport parameters has been operated and the Peclet number, crossing velocity, dispersion coefficient, time to the max, and maximum concentration have been calculated. Eventually, the model's applicability for large-scale porous media has been proven with only one unit of the cells.
Показать больше [+] Меньше [-]A Novel and an Efficient 3-D High Nitrogen Doped Graphene Oxide Adsorbent for the Removal of Congo Red from Aqueous Solutions
2019
Zeraatkar Moghaddam, A. | Ghiamati, E. | Pakar, R. | Sabouri, M. R. | Ganjali, M. R.
The current study both synthesizes and uses four compounds of graphene oxide (GO), nitrogen doped graphene oxide (ND-GO), high nitrogen doped graphene oxide (HND-GO), and three dimensional high nitrogen doped graphene oxide (3D-HND-GO) in order to remove a model anionic dye, Congo red (CR) from wastewaters. It also compares their carbon nano-structure, with regard to removal efficiency and finds out that 3D-HND-G yields higher efficiency in removal of CR, especially at lower pHs. This is due to its better dispersibility and greater surface area. Also, batch adsorption technique has been utilized and all involved parameters that affect the removal efficiency, e.g. initial pH, adsorbent dosage, initial CR concentration, and contact time are examined. The study applies Central Composite Design (CCD) to figure out their efficacies, with the results showing the following optimum conditions for removal of 100 ppm of CR: 4 mg/mL of the adsorbent, pH = 3, and 25 min of contact time. Furthermore, it studies the adsorption activity of the synthesized adsorbent, including kinetics, isotherm, and desorption comprehensibly. The adsorption isotherm is well-fitted through the Langmuir model, exhibiting high CR adsorption capacity. Also, CR adsorption kinetics shows that it has obeyed a pseudo-second-order kinetic model, indicating that adsorption has made the rate-limiting step. In addition, the proposed adsorbent has successfully been applied to reduce the concentration of CR as hazardous dye materials in the water and wastewater samples.
Показать больше [+] Меньше [-]The Environmental Strategic Analysis of Oil & Gas Industries in the Kurdistan Region Using PESTLE, SWOT and FDEMATEL
2019
Koshesh, O. S. | Jafari, H. R.
The need for oil and natural gas as a major source of energy is vital. On the one hand, it has affected the political and economic equations at the international, regional and national level. On the other hand, it has had negative effects on sociocultural, legal, and environmental aspects as well as on the physical and mental health of human beings. Therefore, the need to provide an environmental policy that addresses the various dimensions of the oil and gas industry will be necessary. The present paper aims to set up a conceptual model of environmental policy for sustainable development in the oil and gas industries of the Kurdistan Region through the use of these 6 components: political, economic, sociocultural, technological, legal and environmental. It will also be using the techniques of PESTLE, SWOT, SPACE, FANP, FDEMATEL, and simulation with the VENSIM software. The results show the weights of the criteria respectively are Political; 1.59, Economic; 0.78, Sociocultural; 0.00, Legal; -0.99, Technological; -0.61 and Environmental; -0.70. So that all components are important, but that political and economic factors have a significant influence on environmental policies and oil and gas industries. Sociocultural components have a neutral role and the technological, legal and environmental components are impressible. Finally, fifteen strategies for the formulation of an effective environmental policy in the oil and gas industry were presented.
Показать больше [+] Меньше [-]Identification of the Thresholds of Extreme Values and Synoptic Analysis of PM10 Pollution in the Atmosphere of Ahvaz
2019
Ghavidel, Y. | Khorshiddoust, A. M. | Farajzadeh, M. | Pourshahbaz, H.
Ahvaz can be regarded as one of the most polluted cities in the world in terms of air pollution. Successive years of drought and weather conditions in recent years have resulted in particulate matter (PM10) concentration in Ahvaz. In this study, using probability distribution techniques, an appropriate threshold to identify the PM10 maximum extreme concentrations (MEC) has been detected. Based on log-logistics probability distribution, which has the best fit to the data of PM10 concentration in Ahvaz, the 0.99 percentile threshold which is specified by 1516 μg/m³ is known as the primary PM10 concentrations in Ahvaz air. Based on the mentioned threshold, 24 days in which the PM10 concentration was equal to or more than the threshold were selected for synoptic analysis. Analysis of the circulation of weather types showed that two weather types circulations at 500 hPa level provide the climatic conditions for the occurrence of (MEC) caused by PM10 concentration ≥1516 μg/m³ in Ahvaz in the first type (which is for hot days). Under such condition, the closed high pattern of 500 hPa level is accompanied by the ground low pressures. In the second type (which is for cold and transitional days) the closed high pattern of 500 hPa level is accompanied by the ground high pressures. In addition, this study showed that the (MEC) of PM10 in both models fed with several different sources at different levels and due to being multi-source, storms can create MEC.
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