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Emission Risk Assessment of Toxic Gases of Floating Roof Storage Tanks Полный текст
2022
Doregar Zavareh, Razieh | Dana, Tooraj | Roayaei, Emad | Monavari, Seyed Masoud | Jozi, Seyed Ali
Events such as the emission of toxic gases are possible on floating roof storage tanks. Since gasoline is a high-consumption and volatile product stored in adjacent oil depots or large cities, it is necessary to assess their emission risk. Given that the multi-criteria methods allow the identification of and assessment of the indicators well and allow the participation of expert experts, so the FAHP method has been used to identify and assess the risk before the emission of toxic gases. The results showed the importance of 7 factors among 36 factors, 3 of which were related to equipment error. The DOW'S CEI method was used to assess the emission risk if the event occurred. This method provides safe boundaries based on Emergency Response Planning Guidelines (ERPGs), where the results indicate the settlement placement around the oil repository in the range of the predicted concentration at all three levels of ERPG.
Показать больше [+] Меньше [-]Assessment of groundwater and surface water pollution by hazardous metals, using multivariate analysis and metal pollution index around the old Sidi Kamber mine, NE Algeria Полный текст
2022
khelfaoui, malika | Benaissa, Amina | Kherraf, Sihem | Madjram, Mohamed Salah | Bouras, Ibtissem | Mehri, karima
In order to evaluate the impact on water quality of the abandoned Sidi Kamber mine in Skikda, NE Algeria, Pb, Zn, Cd, Fe, Cu, Mn and Ni metals were collected at surface water and groundwater, from twenty eight sites located near the mine. Conventional hydrochemical methods, heavy metal pollution index (HPI) and multivariate statistical analysis techniques: correlation matrix (CM), principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used. Surface water results show that El-Souk River has a high level of pollution, but Guenitra dam water is less contaminated. Regarding the groundwater results, the wells and springs are not suitable for drinking. The overall quality estimated by HPI values of surface and groundwater are poor; they may pose a potential health risk to the local population. The PCA and HCA suggest that surface water and groundwater are contaminated by two sources: anthropogenic and natural. According to the obtained results, surface water and groundwater pollution state of this area raises serious concerns about health and environment.
Показать больше [+] Меньше [-]A Review of the Application of Machine Learning and Geospatial Analysis Methods in Air Pollution Prediction Полный текст
2022
Zhalehdoost, Alireza | Taleai, Mohammad
During the past years, air quality has become an important global issue, due to its impact on people's lives and the environment, and has caused severe problems for humans. As a prevention to effectively control air pollution, forecasting models have been developed as a base for decision-makers and urban managers during the past decades. In general, these methods can be divided into three classes: statistical methods, machine learning methods and hybrid methods. This study's primary intent is to supply an overview of air pollution prediction techniques in urban areas and their advantages and disadvantages. A comparison has also been made between the methods in terms of error assessment and the use of geospatial information systems (GIS). In addition, several approaches were applied to actual data, and the findings were compared to those acquired from previous published literatures. The results showed that forecasting using machine learning and hybrid methods has provided better results. It has also been demonstrated that GIS can improve the results of the forecasting methods.
Показать больше [+] Меньше [-]School Indoor Air Pollutants: In Relation to Allergy and Respiratory Symptoms among School Children in Urban Areas Полный текст
2022
Hashim, Zailina | Mohamad Fadzil, Nur Shahira | Mohd Fuad, Siti Raihan | Shamsudin, Shamsul Bahari | Mohd Isa, Khairul Nizam | Song, Tan Tek | Sieman, Jony | Mohd Elias, Saliza | Hashim, Jamal Hisham
Indoor air pollutants affect children’s health and previous research mostly focuses on respiratory and allergic diseases. However, little is known about the risks among school children in East Malaysia. Therefore, we studied associations between school children’s respiratory and allergic symptoms and indoor air pollutants in schools in Sabah, Malaysia. We randomly enrolled 332 school children (14 years old) from 24 classrooms in 6 secondary schools in Kota Kinabalu, Sabah. Information on personal characteristics, respiratory and allergic symptoms were gathered by using a standard questionnaire. The skin prick test was used to characterize the atopy. In each classroom, the indoor concentrations of particulate matter (PM10 and PM2.5), nitrogen dioxide (NO2), formaldehyde, total volatile organic compounds (TVOC), carbon dioxide (CO2) temperature and relative humidity were monitored. Overall, 11.7% reported doctor-diagnosed asthma, 14.8% wheezing, 17.5% day-time breathlessness, 37.0% breathlessness after exercise, 13.0% breathlessness at night-time, 55.1% rhinitis and 10.8% skin allergic in the last 12 months. Regression analysis showed that the onset of wheezing was common in doctor-diagnosed asthma (OR= 8.29, 95% CI= 3.70-16.10) and with parental asthma/allergy (OR= 2.13, 95% CI= 1.10-4.15), and associated with concentrations of NO2 (OR= 1.03, 95% CI= 1.01-1.21) and CO2 (OR= 1.01, 95% CI= 1.01-1.11). Day-time breathlessness was associated with indoor NO2 (OR=1.02, 95% CI= 1.02-1.35) and TVOC (OR= 1.30, 95% CI= 1.10-1.52). The indoor concentrations of NO2, CO2, TVOC and PM2.5 as well as parental asthma/allergy, and parental smoking were associated with the outcome of respiratory and allergic symptoms.
Показать больше [+] Меньше [-]Rapid ecological resilience assessment of urban forest parks: An alternative approach Полный текст
2022
Darabi, Hassan | Hamedi, Roghaye | Ehsani, Amirhoushang | Kafi, Mohsen
Abstract Rising threats, such as climate change, have thus far resulted in disruptions to ecosystems. Therefore, ecological resilience (eco-resilience) to absorb such distractions and maintain the capacity of ecosystems has been the focal point of numerous studies. In most cases, the characteristics of ecosystems are considered as indicators shaping this type of resilience. In this study, an alternative approach was adopted to examine the performance and outcomes of an ecosystem instead of reflecting on affective factors. Therefore, the resilience index (RI) of an urban forest park was assessed using eco-functional indicators, such as eco-volume (Veco), eco-height (Heco), bio-volume (Vbio), and eco-volume (Veco). At first, the forest park zoning was done. Then, each of the introduced indicators was calculated based on its specific parameters. Finally, the RI of the urban forest park was premeditated. The results showed that each zone with more effective Veco, Heco, and Veco gained a higher score in terms of resilience. The obtained score for RI was thus the function of the current ecological state of each zone. The study conclusions also confirmed that the outputs of the applied framework could embody the main indicators of resilience assessments (viz. thresholds, adaptive capacity, and self-organization). The application of this model on a larger scale required further studies.
Показать больше [+] Меньше [-]Complex application of microbiological characteristics in bottom sediments and biochemical parameters of mussel Mytilus galloprovincialis (Lam.) for assessing the ecological state of marine coastal areas Полный текст
2022
Skuratovskaya, Ekaterina | Doroshenko, Yuliya
Comparative analysis of microbiological indicators (heterotrophic and hydrocarbon-oxidizing bacteria) in bottom sediments and biochemical parameters (level of oxidized proteins (OP) and lipid peroxidation (LPO), superoxide dismutase (SOD), catalase (CAT), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities) in hepatopancreas of mussel Mytilus galloprovincialis (Lam.) from three Sevastopol bays - Laspi, Kazach’ya, Streletskaya (the Black Sea) was carried out. The results obtained allowed to identify certain differences between the studied areas and characterize their ecological state. The maximum abundance of heterotrophic and hydrocarbon-oxidizing bacteria was found in the most polluted Streletskaya Bay (95,000 and 250 cells/g respectively), the minimum - in the conventionally pure Laspi Bay (2,500 and 1.5 cells/g respectively). Parameters of prooxidant-antioxidant system (level of OP and LPO, SOD and CAT activities), as well as ALT activity in the hepatopancreas of mussels from Streletskaya Bay were found higher as compared to those in other tested areas. Most significant differences (more than twofold) in SOD activity, LPO content and basic ketone forms of OP levels were found between Laspi and Streletskaya bays. The results obtained indicate the severe pollution and less favorable living conditions for aquatic organisms in Streletskaya Bay, as well as demonstrate the high level of biochemical adaptation of mussels to complex environmental pollution. The studied parameters can be applied in the ecological monitoring of the coastal sea water areas.
Показать больше [+] Меньше [-]Studying the photostabilization activity of Poly(Vinyl Chloride) films containing 4-amino-5-(((5-methyl-1H-benzo[d]imidazol-2-yl)thio)methyl)-2,4-dihydro-3H-1,2,4-triazole-3-thiol with a dibutyltin complex Полный текст
2022
Mahmood, Zinah | Alias, Mahasin | Kadhom, Mohammed | Bakir, Shaimaa | Yusop, Rahimi | Husain, Amani | Yousif, Emad
A new traiazole derivative (4-amino-5-(((5-methyl-1H-benzo[d]imidazol-2-yl)thio)methyl)-2,4-dihydro-3H-1,2,4-triazole-3-thiol, (L), was employed as a chelating ligand to form a dibutyltin chloride complex and improve the poly(vinyl chloride) (PVC) properties. The doped PVC films were characterized via FT-IR, UV-Vis spectrum, elemental analyses (C, H, N, and M (metallic)), and magnetic susceptibility and conductivity measurements. These characterizations were conducted at room temperature, and it was disclosed that the chelating ligand rules as a bidentate chelate. The photostabilization examination of plain and L-doped PVC films was conducted in the presence of ambient air using the accelerating weather tester, where the doping ratio was fixed to 0.5 wt.%. The photostabilization performance of the additive was evaluated by tracking the indexes of carbonyl (ICO), polyene (IPO), and hydroxyl (IOH), and weight loss relationship with irradiation time. It was noticed that the values of ICO, Ipo, and IOH enhanced with the irradiation time, where this improvement relied on the presence of the Bu2SnL complex.
Показать больше [+] Меньше [-]Levels of Heavy Metals in the Water, Sediments, and Tissues of Golden Apple Snail (Pomacea canaliculata) from Lake Dakong Napo, Esperanza, Agusan del Sur, Philippines Полный текст
2022
Cuadrado, Jerry | Plaza Burlat, Marriane Joy | Ugay Diola, Johanna Louise | Barrera Cusap, Robertson Mari
This study was conducted in order to assess the level of heavy metals in the water, soil, and tissues of Pomacea canaliculata from Lake Dakong Napo, Esperanza, Philippines as well as identify the histopathological alterations in the gonads and muscles of the snail. Heavy metals were detected using Atomic Absorption Spectrometry and slides for histological studies were prepared using histological routine procedure. Results revealed that in sediments Cr (174.67±62 mg/L) and Ni (269.33±17.56 mg/L) were above from the recommended safe limits of the international standards, US EPA (≤25) and FAO (≤50) while concentrations of Pb (16.35± 0.58 mg/L), Cd (5±1.42 mg/L), and Cr (1±0 mg/L) in water were above from the recommended safe limits of the national standards, DAO (≤0.05; ≤0.01; ≤0.05). These heavy metals were below the permissible limits in the gonads and muscles of P. canaliculata however, alterations in the tissues of the snail are evident suggesting that these heavy metals and other environmental stressors are negatively affecting the organisms inhabiting the lake.
Показать больше [+] Меньше [-]Assessment of Microplastics Distribution and Related Water Quality in an Urban Canal, Thailand Полный текст
2022
Eamrat, Rawintra | Taweesan, Achara | Pussayanavin, Tatchai
Microplastics pollution has become a matter of global concern because of its effects on aquatic life and the ecosystem. This study investigated the abundance and types of microplastics found in an urban canal of Thailand. Water quality and the relationship between microplastics pollutants and the physicochemical properties of water quality were also analyzed to provide evidence for this study. The mean abundance of microplastics was 370 ± 140 particle(p)/m3. The highest number and concentration of microplastics were found on surface water corelated with urbanization. Transparent brown and transparent colors in the form of film and fiber/lines were the predominant morphology. Polypropylene (PP) and polyethylene (PE) were the most abundant polymer type in all surface water samples. Furthermore, water quality was related with microplastic pollution. The physicochemical properties of turbidity (0.99), conductivity (0.97), total solid (0.95) and biological oxygen demand (0.84) were accounted for greatest influences on microplastics distribution. The estimated equation of microplastics was also closely corelated with water quality. These results demonstrate that microplastic pollution has progressed more in poor water quality than good water quality, indicating that the inflow process and sources of microplastics are similar to those of other pollutants. Therefore, this study is expected to encourage and enforce solid waste and wastewater management policies that prevent microplastics pollution in the environment.
Показать больше [+] Меньше [-]Optimization of Detention Time for Domestic Wastewater Treatment using Phycoremediation Полный текст
2022
Moondra, Nandini | Jariwala, Namrata | Christian, Robin
In developing countries, wastewater treatment is confined to secondary systems. Hence even after treatment, wastewater effluent has a high level of nutrients which causes eutrophication and has destructive impacts on receiving bodies. Literature reveals that phycoremediation can be the best solution to address the problem faced but is time-consuming, ranging from days to weeks. Hence, the present study aimed to determine an optimum detention time for the microalgal system to treat domestic wastewater. The retention time for treatment in the study was divided into an aeration and settling periods. During the study, aeration time varied from 2 hours to 24 hours, followed by 1-hour settling period for each aeration time. Optimum detention time for microalgal treatment was obtained at 11 hours of detention time (10 hours aeration and 1-hour settling). Parameters analyzed during the study were pH, EC, TS, TSS, TDS, nitrate, phosphate, ammonia, COD and DO. However, the main focus was on nutrients (phosphate and ammonia) and organics (COD) removal while determining the optimum detention time. Maximum removal efficiency obtained for COD, ammonia and phosphate for non-filtered effluent was 75.61%, 90.63% and 83.29%, respectively. However, removal efficiency further increased for filtered effluents to 86.34%, 100% and 91.12% for COD, ammonia and phosphate, respectively. Algal treatment offers an ecologically safe and more affordable system for nutrient removal and eliminates the need for tertiary treatment.
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