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The Effectiveness of the Ballast Water Exchange Method in Removal of the Heavy Metals in the Ballast Tanks of the Ships, Bushehr Port- Persian Gulf 全文
2020
Tolian, R. | Javadzadeh, N. | Sanati, A. M. | Mohammadi Roozbahani, M. | Noorinejad, M.
Ships transport about 80 percent of world trade and transfer approximately three to five billion tons of ballast water internationally every year. Due to the likely presence of pollutants, the ballast water discharged by ships can have negative effects on aquatic ecosystems. This study was conducted on 10 ships that entered the Bushehr port to determine the effectiveness of the ballast water exchange method and also to specify the contents of heavy metals (Ni, Cd, Pb and Cu) in the water and sediment of the ships’ ballast tanks. The samples were collected from January 2017 to July 2018 during a cold and a hot season. The results indicate the values of heavy metals in the samples in this order: Ni> Cu > Pb > Cd. The heavy metals concentrations in the sediment samples did not exceed the standard of the National Oceanic and Atmospheric Administration (NOAA). Whereas, Cu and Ni in all water samples and Cd in samples 2 and 7 exceeded the NOAA quality standard value. A correlation analysis of the metals showed that the sources of heavy metals vary in water and sediment samples, except for Pb and Cu in sediment samples which a positively significant relationship were observed. The results also revealed that the ballast water exchange method cannot by itself be effective and an efficient management together with continuous monitoring seems to be essential to prevent pollution of the ballast tanks of the ships entering the Bushehr port.
显示更多 [+] 显示较少 [-]Overall D. melanogaster Cohort Viability as A Pollution Indicator of the Atmospheric Air of Urban Landscapes 全文
2020
Rudenko, S. S. | Leheta, U. V. | Rudenko, V. P. | Kostyshyn, S. S. | Bialyk, V. D.
The method of air pollution level evaluation of urban landscapes on the basis of D. melanogaster cohort analysis has been suggested. The method implies the binding to the landscape areas of the city. Within each landscape area traps and cultivators for D. melanogaster have been installed in sanitary-protective zones of various enterprises as well as on the background territory with the least level of anthropogenic load serving as the control. Based on specifically elaborated technique for field conditions, the amount of eggs, third instar larvae, pupae and imago has been calculated. Then, using the computer program ImageJ, the square under the curves of cohort survival has been determined which is considered overall cohort viability (OCVD.m). The previously mentioned indicator considers cohort survival at all stages of ontogenesis. In addition, the expressed in percentage indicator of oppression (IO OCVD.m) in relevance to the control OCVD. m affects the level of air pollution of urban landscapes by emissions of various enterprises. The relevance between these indicators is determined by a four-level scale elaborated specifically for the purpose. The method has been tested based on technogenic landscapes of Chernivtsi, Ukraine. The sensitivity of the suggested indicator for a wide range of pollutants has been proved and its ability to respond to different levels of greening of similar enterprises has been shown.
显示更多 [+] 显示较少 [-]Chronological Studies of Traffic Pollution Using Elemental Analysis of Tree Rings: Case Study of Haatso-atomic Road 全文
2020
Edusei, G. | Tandoh, J. B. | Edziah, R. | Gyampo, O.
Mitigation of atmospheric pollution has been a topic of concern over the past decades. In this study, tree rings have been used to reconstruct past climates as well as to assess the effects of recent climatic and environmental changes on tree growth. Vehicular emission is one of the major sources of pollutants in the atmosphere and this study focused on the Haatso-Atomic road which over the years has been a spot for heavy vehicular traffic. Swietenia mahagoni (Mahogany) tree was logged and the rings counted and age determined to be 61 years spanning from 1957 to 2018. X-ray fluorescence (XRF) was used to investigate the presence of the following heavy metals. Heavy metals (Cu, Mn, Zn, Pb, Cd and Ni) which ranged from (3.15—9.84mg/kg), (2.58 – 5.49 mg/kg), (8.18 – 15.78mg/kg), (0.12—0.60 mg/kg), (0.01—0.09 mg/kg) and (0.10 – 0.99 mg/kg) respectively, from vehicular emissions were determined for annual rings spanning from 1957 to 2018 and surprisingly an increasing trend was observed with some the heavy metals exceeding WHO guidelines. Tree growth rates were calculated through ring width measurements and related to annual precipitation data spanning over the sampling period. It was observed that wet seasons correlate with high growth rates of trees while low precipitations seasons related to low or no growth rate of trees.
显示更多 [+] 显示较少 [-]Artificial Neural Network Modeling for the Management of Oil Slick Transport in the Marine Environments 全文
2020
Janati, M. | Kolahdoozan, M. | Imanian, H.
Due to an increase in demand of petroleum products which are transported by vessels or exported by pipelines, oil spill management becomes a controversial issue in coastal environment safety as well as making serious financial problems. After spilling oil in the water body, oil spreads as a thin layer on the water surface. Currents, waves and wind are the main causes of oil slick transport. These phenomena depend on the overall interaction among gravity, viscosity, surface tension and interfacial tension of oil in water bodies. In the current study, Artificial Neural Network (ANN) models have been designed and trained for the prediction of oil spreading and advection under different hydrodynamic conditions. In this regard, results obtained from a multiphase Lagrangian numerical model are deployed to train ANN model. The mentioned numerical model which is based on the moving particle semi-implicit (MPS) method is developed in the earlier stage of the study. In this research study, the MPS numerical model is first validated and verified against the analytical formulas which are based on experimental data cited in the literature. Then, various hydrodynamic conditions and oil spill scenarios were chosen to obtain different numerical model results. Finally, numerical model results are then deployed for training ANN model to provide a useful tool for urgent prediction of oil slick trajectory in order to manage the oil slick transport in the coastal environments.
显示更多 [+] 显示较少 [-]Estimation of Phosphorus Reduction from Wastewater by Artificial Neural Network, Random Forest and M5P Model Tree Approaches 全文
2020
Kumar, S. | Deswal, S.
This study aims to examine the ability of free floating aquatic plants to remove phosphorus and to predict the reduction of phosphorus from rice mill wastewater using soft computing techniques. A mesocosm study was conducted at the mill premises under normal conditions, and reliable results were obtained. Four aquatic plants, namely water hyacinth, water lettuce, salvinia, and duckweed were used for this study. The growth of all the plants was inhibited in rice mill wastewater due to low pH, high chemical oxygen demand, high conductivity, and high phosphorus concentration. Subsequently, a 1:1 ratio of mill water to tap water was used. A control was maintained to assess the aquatic plant technology. In this study, the aquatic plants reduced the total phosphorus content up to 80 % within 15 days. A comparison between three modeling techniques e.g. Artificial neural network (ANN), Random forest (RF) and M5P has been done considering the reduction rate of total phosphorus as predicted variable. In this paper, the data set has been divided in two parts, 70 % is used to train the model and residual 30 % is used for testing of the model. Artificial neural network shows promising results as compared to random forest and M5P tree modelling. The root mean square error (RMSE) for all the three models is observed as 0.0162, 0.0204 and 0.0492 for ANN, RF and M5P tree, respectively.
显示更多 [+] 显示较少 [-]Phytotoxicity of Lead and Chromium on Germination, Seedling Establishment and Metal Uptake by Kenaf and Mesta 全文
2020
Sultana, R. | Islam, S. M. N. | Zaman, M. W. | Uddin, N.
Heavy metal contaminated soil raises major global environmental and agricultural concern. Recently soil pollution through lead (Pb) and chromium (Cr) becoming serious problem and remediation or utilization of those contaminated soil with potential crops is of the outmost importance. The objectives of present study were to examine the effects of Pb and Cr on three different kenaf and mesta varieties for seed germination, seedling establishment and amount of Pb and Cr uptake by tested varieties in laboratory condition. Three varieties were used for the study namely, HC-95 (kenaf), CPL-72126 (mesta) and Samu-93 (mesta) and the treatments were combination of Pb and Cr chemical at (0,0), (60,60), (80,80), (100,100) and (120,120) mg/L. Increased level of lead and chromium gradually reduced the germination percentage and primary growth parameters compared to control. The shoot and root lengths were affected only little, whereas, the biomass showed a considerable reduction with the increase of Pb and Cr toxicity. Stress tolerance indices showed a gradual and negative response by the plant with the increase of metal concentrations. However, in all the levels of Pb and Cr treatment, the seedlings were capable to tolerate the toxicity and seedlings were established. Bioaccumulation of Cr was higher than that of Pb in all varieties and in all treatments. The interaction of Pb and Cr reduced the toxic effect of both metals to the plants. The findings are helpful for selecting fiber crop varieties for cultivation in contaminated soils or phytoremediation of Pb and Cr from the contaminated soils.
显示更多 [+] 显示较少 [-]Fixed Bed Column Modeling of Cd(II) Adsorption on Bone Char Using Backward Bayesian Multiple Linear Regression 全文
2020
Amiri, M. J. | Mahmoudi, M. R. | Khozaei, M.
In this work, the backward Bayesian multiple linear regression (BBMLR) as a new approach is presented to predict the adsorption efficiency (AE) of Cd(II) ions by ostrich bone char (OBC) in the fixed bed adsorption with four operational variables consisting of pH (2-9), inlet Cd(II) concentration (Co= 25-100 mg/L), bed depth (h= 3-9 cm) and feed flow rate (Q= 0.5-30 mL/min). The performance of the BBMLR was evaluated using the coefficient of determination (R2), normalized root means square error (NRMSE) and mean residual error (MRE). The AE of Cd(II) ions by OBC increased from 42.3% to 99.9% when pH was increased from 2 to 9 with h of 6 cm and Q of 1.5 mL min-1. It was found that the AE dramatically increased from 70.5% to 99.9% with decreasing Q from 30 to 0.5 mL min-1 at pH of 7 and h of 6 cm. At pH= 7 and Q= 1.5 mL min-1, the AE increased from 71.9% to 100% when h increased from 3 to 9 cm. The BBMLR model presented excellent performance (NRMSE=6.69%) for predicting Cd(II) removal in a continuous adsorption system, although it gave a slight underestimation (approximately 3.52%). The BBMLR is more sensitive to the pH, followed by h and Q, while the Co has no significant effect on it. This research displays that OBC has great potential as an eco-friendly low-cost adsorbent in removing Cd(II) ions from the contaminated waters.
显示更多 [+] 显示较少 [-]Dust Crises and its Regional Geopolitical and Security Impact in West Asia 全文
2020
Abdi, A. | Yazdanpanah, Q. | Javadi, Z.
Western Asia has recently become an arena for significant upheavals of various kinds, be it political, safety-related, geopolitical, social, etc. These have in turn focalized the salience of the region as well as its ensuing situation and challenges on a global perspective. Such a naturally-born phenomenon is characterized, amidst other factors, by its transregional quality, granting it some sort of geopolitical peculiarity. The occurrence of haze would implicate a merged endeavor on part of the countries, engaged in this cross-regional abnormality. This joint endeavor is, however, hindered and at times exacerbated due to certain political inconsistencies among the countries, undoubtedly rising from differences in ideology, religion, politics, and social standards. In this light, the present study seeks to inquire the impacts of haze, as a geopolitical phenomenon, on involved countries. It also tries to find out whether subsequent implications of this predicament could in effect be employed to establish new relations among rather-standoffish nations or if they are merely components of a cold relation among countries and could intensify each nation’s problems, reducing the overall quality of life further. The findings indicate that despite the existent domestic and transregional problems, public opinion tends to establish joint cooperation among the engaged countries. This is not in the least a result of fear of a low life quality among the inhabitants of the said nations.
显示更多 [+] 显示较少 [-]Decolorization of Reactive Black-5 High Concentration by Vermicompost Microflora and Detoxification of By-Products by UV-C/H2O2 Post-Treatment 全文
2020
Emadi, Z. | Sadeghi, M. | Mohammadi-moghadam, F. | Sadeghi, R. | Forouzandeh, S. | Sadeghi, R.
The presence of synthetic dyes in textile wastewater is a problematic issue for environmentalist. Nowadays, dye removal is practiced via different methods. Among all these methods, biodecolorization is an ideal technique. The present research apples vermicompost microflora to remove reactive black- C, pH = 7, and under anaerobic condition. At 36h, removal efficiencies of 94.79%, 94.06%, and 93.6% are obtained for concentrations of 800, 850, and 950 mg/ L, respectively. It has also been observed that when the initial concentration rises to 1400 mg/ L, the efficiency drops to 51.57% at 36h. Also, methyl red, methyl orange, eriochrome black-t, and acid blue-113 could be decolorized by the isolated bacterial strain with an efficiency of 94.29%, 92.10%, 90.83%, and 88.95%, respectively. Phytotoxicity Test shows that the parent form of reactive black-5 has not been toxic for the seeds (100% germination for Triticum aestivum and 90% for Maize). When reactive black-5 is treated with isolated bacterial strain under anaerobic condition, none of the seeds remain germinated which might be due to the possible formation of toxic aromatic amines intermediates. Therefore, ultraviolet C + 100 mM H2O2 has been used as the post-treatment process for detoxifying of by-products. After the integrated treatment of synthetic wastewater, containing RB-5, complete germination (100%) of Triticum aestivum and Maize is observed. In the post-treatment process, due to the generation and activation of hydroxyl radicals, the toxic aromatic amines compounds convert to the less toxic compounds.
显示更多 [+] 显示较少 [-]Assessment of Disposal Scenarios for Solid Waste Management Using Fuzzy Rapid Impact Assessment Matrix; a Case Study of Khorramabad Industrial Estate 全文
2020
Ghobadi, M. | Ahmadipari, M. | Pazoki, M.
The present paper tries to assess different scenarios for solid waste management in Khorramabad industrial park. It uses a new hybrid method of fuzzy Rapid Impact Assessment Matrix, and proposes the Fuzzy theory, the ranking method of which is innovated so that the accuracy and flexibility of the RIAM method could be improved. Four scenarios are studied, namely open dumping, sanitary landfill, gasification, and incineration. They are then evaluated in terms of their physical/chemical, biological/ecological, social/cultural, and economic/operational effects. Afterwards, two scenarios have been selected with the aim of energy production. The evaluation of these aspects for each scenario is in accordance to the expert's judgments and field study, with the results showing that sanitary landfill has had the least undesirable effects. Hence, this approach is selected as the best scenario for waste management in the studied area. According to the obtained results, it is suggested to consider sanitary landfills as the main part of the waste management hierarchy program of the studied area. Also, it is highly recommended to use the Fuzzy RIAM technique in similar studies and to compare the results with the new ones in order to examine the accuracy of the new improved method.
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