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Assessment of commute-related emission reduction scenarios for administrative services
2024
Oveisi, Shima | Moeinaddini, Mazaher
Mobile sources from administrative service commutes significantly contribute to air pollutant emissions in metropolises, underscoring the need for travel demand management (TDM) and referral reduction strategies. A software-oriented approach is crucial in metropolises like Karaj due to the high commuting volume. Evaluating pollutant emissions across scenarios offers insights for effective air pollution reduction strategies. Scenarios aim to assess air pollution management, considering software and hardware aspects. Data collection involved field interviews and questionnaires for individuals commuting to administrative offices. These challenges and considerations informed the classification of the studied vehicle fleet based on system types, production years, emission standards, fuel types, and vehicle classes. We designed scenarios to minimize standard pollutants by reducing in-person visits to administrative offices and replacing the fleet with hybrid and natural gas vehicles. Results were compared with the baseline scenario, computing emissions using the International Vehicle Emission Model (IVE). The comparative analysis highlighted that substantial pollutant reduction comes from combined commuting reduction and a decrease in referral numbers. TDM emerged as the most cost-effective strategy, executed with principled planning. In conclusion, this study's scenario exploration provides insights for policymakers and urban planners. Adopting a software-oriented approach to mitigate air pollutant emissions through commute reduction and strategic TDM can significantly enhance air quality and curb traffic-related pollution in cities like Karaj.
显示更多 [+] 显示较少 [-]Examination of Medicinal Plants for Radionuclide Absorption and their Health Implications
2024
Popoola, Felix | Isola, Oladotun | Fakeye, Oluseye | Owolabi, Tunde | Sanyaolu, Modupe | Owoyemi, Sheu | Elijah, Isaac
This study examined the concentrations of 40K, 238U, and 232Th radionuclides and evaluated the possible radiological health risks to medicinal plants found in Ewu, Edo State, Nigeria, using a NaI(Tl) gamma spectrometer. The six selected medicinal plants were Mangifera indica, Dacryodes edulis, Terminalia catappa, Cymbopogon citratus, Anacardium occidentale, and Persea Americana. The results showed that the activity concentrations for 40K ranged from 146.59 ± 4.81 in Persea americana to 296.08 3.42 Bq/kg in Cymbopogon citratus, with a mean of 209.43 ± 5.14 Bq/kg; 238U ranged from 2.25 ± 0.06 to 5.57 ± 0.15 Bq/kg, with a mean of 4.73 ± 0.15 Bq/kg; and 232Th varied from 4.50 ± 0.35 to 12.07 ± 0.57 Bq/kg, with a mean of 8.00 ± 0.40 Bq/kg. The maximum and minimum activity concentrations of both 238U and 232Th were found in Mangifera indica and Cymbopogon citratus, respectively. The calculated average committed effective dose ECED was 0.130 μSv/yr and the excess lifetime cancer risk (ELCR) has a mean of 0.00913 (×〖10〗^(-3)). The radiological hazard assessment of the investigated medicinal plants was well within the internationally recommended safe limits of 0.3 mSv/yr and >〖10〗^(-4) for ECED and ELCR respectively. 232Th contributes 54.91% of the total ECED, while 238U contributes the least to 6.35%. 232Th exhibits a very strong, positive, and significant relationship with ECED and the ELCR, and it contributes largely to the ECED and ELCR due to ingestion of the examined herbal plant. Therefore, these medicinal plants are radiologically safe for human consumption.
显示更多 [+] 显示较少 [-]Removal of microplastics from synthetic wastewater via sono-electrocoagulation process: modeling and optimization by central composite design
2024
Ghadami, Mahshid | asadi-Ghalhari, Mahdi | Izanloo, Hassan | Alasvand, Shokoufeh | Tabatabaei, fatameh sadat | Mostafaloo, Roqiyeh | Omidi Oskouei, Alireza | Ghafouri, Nasim
Wastewater treatment plants are an important pathway for microplastics (MPs) to enter the environment. In recent decades, hybrid treatment technologies such as sono-electrocoagulation have been used to treat various types of wastewater. This study aimed to remove polypropylene microplastics from synthetic wastewater by sono-electrocoagulation process using central composite design. The central composite design was utilized to investigate the relationship among four independent variables including the number of MPs (0.003-0.03 MPs/L), sodium sulfate concentration (180-9000 mol/L), voltage (1-15 V) and reaction time (20-180 min) on the efficiency of polypropylene microplastic. Design Expert 13 software and central composite design method were used to design and analyze the experiments and results. The optimum number of concentration of MPs, sodium sulfate concentration, voltage, and reaction time were found to be 6343.36 MPs/L, 0.0181924 mol/L, 10.0356 V, and 62.21 min, respectively. In optimal conditions, polypropylene removal was found to be %90.34. Central composite design proposed a quadratic model for this process. Adequacy of the model using lack of fit statistical tests values, p-values, and F-values was checked, yielding the values of were 1.76, 0.0001 ˂, 19.51, respectively. The R2, R2 adjusted, R2 predicted values which were 0.9367, 0.8776, 0.6959, respectively. Considering the proper removal efficiency, the sono-electrocoagulation process can be used to remove microplastics.
显示更多 [+] 显示较少 [-]Treatment of Textile Wastewater Through Constructed Wetland Coupled Microbial Fuel Cell by Canna indica
2024
Sheoran, Deepika | Singh, Simranjeet
Constructed wetland coupled microbial fuel cell (CW-MFC) encompasses both aerobic and anaerobic zones to produce electrical energy while facilitating the oxidative breakdown of pollutants. In this study, we ascertained the effective setup of CW-MFC in order to assess the pollutant removal efficiency and electricity generation. The CW-MFC system was initially filled with textile wastewater. Stainless steel mesh with granular activated carbon as the anode and graphite rods as the cathode were used. Soil and gravel were used as substrates and Canna indica as macrophyte. Over the course of 4 weeks, regular assessments were conducted every 3rd day to monitor the alternations in the wastewater properties. Throughout the treatment phase, the planted CW-MFC system achieved a significant reduction in phosphate, nitrate, BOD, COD, and chloride as compared to the unplanted CW-MFC system. From this study, the results also show that planted CW-MFC produce maximum peak voltage (0.112V) and current (1.12 mA) in comparison to CW-MFC without plants. Consequently, the finding suggests that Canna indica possesses the capacity to treat textile wastewater.
显示更多 [+] 显示较少 [-]Metals Ti, Cr, Mn, Fe, Ni, Cu, Zn and Pb in Aquatic Plants of Man-made Water Reservoir, Eastern Siberia, Russia: Tracking of Environment Pollution
2023
Vladimirovna Chuparina, Elena | Igorevna Poletaeva, Vera | Vladimirovich Pastukhov, Mikhail
The paper reports the results of research on the Bratsk water body (Russia), the hugest man-made reservoir in the world, using aquatic plants as bioindicators. This aquatic environment requires constant monitoring due to metal emissions by metallurgical, machine-building, and other industries. To that end, the accumulation capacities of Myriophyllum spicatum L., Elodea canadensis Michx., Potamogeton pectinatus L. and Cladophora glomerata L. were compared. The Ti, Cr, Mn, Fe, Ni, Cu, Zn, and, Pb contents in the plants were quantified with X-ray fluorescence. The calculated bioaccumulation indexes provided similar indicator characteristics of these species. The clustering analysis specified the spatial metal pollution in the reservoir. The aquatic plants sampled near industrial enterprises demonstrated the high concentrations: Ti (573-887), Cr (14-22), Mn (609-1080), Fe (9231-12724), Ni (8-11), Cu (51-103), Zn (35-45) and Pb (10-40) µg/g. The average concentrations in the samples collected away from emission sources were significantly lower: Ti (443-598), Cr (7-10), Mn (439-591), Fe (4575-6573), Ni (6-7), Cu (36-58), Zn (27-33) and Pb (6-9). While, they were several-fold higher than threshold values reported for the Lake Baikal plants: Ti – 6; Cr – 2-2.6; Ni – 1.9; Fe – 3-6.7; Mn – 1.5-2.6; Cu – 4; Zn – 1.2-2, and Pb – 7.3. In addition to industrial impacts, the sedimentation processes, coastal erosion, wood rotting and ore occurrences caused increasing in metal contents. Assessment of pollution through the pollution load index and the integration Nemerov index provided the classification of the environment of the Bratsk water reservoir as polluted one.
显示更多 [+] 显示较少 [-]Polycyclic Aromatic Hydrocarbons In Bottom Sediments Of Donuzlav Lake (Black Sea)
2023
Soloveva, Olga | Tikhonova, Elena | Barabashin, Timofey
Lake Donuzlav, located in the western part of the Crimean Peninsula is a water body undergoing anthropogenic load, which cannot but affect the state of its bottom sediments. The content and composition of polycyclic aromatic hydrocarbons (PAH) are representative indicators of the degree and character of an anthropogenic impact in natural habitats. The aim of the work was to assess the level of PAH content in the bottom sediments, to identify potential sources and to assess the toxicity of bottom sediments. It was established that the average content of ∑PAH in the sediments amounted to 806±380 ng/g, with the values of this parameter ranging over 34–4036 ng/g. At five out of ten stations in Lake Donuzlav, PAH values, average for the Black Sea, were exceeded. These stations were grouped along both banks in the inner part of the reservoir. Fourteen PAHs were identified: Nap, 2mNap, Flu, Phe, Ant, Fla, Py, TrPhe, Chr, BbF, BkF, BaP, DBA, BghiP. The main share falls on the binuclear Nap and 2mNap, which indicate the presence of fresh oil pollution. The average share of these compounds over the water area was 60±5%, and at stations with elevated levels of ∑PAH it was 74±4%. There was a close correlation between the content of all polyarenes, which coefficient averaged 0,88. The presence of geochemical relationships between polyarenes entering from different sources was probably due to the functioning of natural mechanisms aimed at the transformation of pollutants, which served to restore the dynamic balance of the system.
显示更多 [+] 显示较少 [-]The Rhizospheric Soil of Sparganium erectum L. Plant: A new Source of Efficient Bacteria for Azo Dye Decolorization
2023
Nikkhah, Masoumeh | Pourbabaei, Ahmad Ali | Shariati, Shayan | Shakiba, Mina
The purpose of our study was to identify the native bacteria with the ability to degrade azo dyes from the rhizosphere of Sparganium erectum L., and Typha latifolia L. plants that were grown on a drain of a textile mill. Eight and one strain with decolorization ability of Cibacron Brilliant Red EB and Terasil Red 3BL-01 were isolated from the saline rhizosphere of Sparganium erectum L. and latifolia L. plant respectively. Results showed that the bacteria isolated from the rhizosphere of Sparganium erectum L. are more capable of decolorizing azo dyes. Based on the 16S rRNA sequencing, selected strains were identified as follows: Enterobacter ludwigii strain SNP3 (OL719291), Rhodococcus fascians strain SNP5 (OL759129), Pseudomonas aeruginosa strain SNP10 (OL759126), and Bacillus safensis strain SNP13 (OL759127). The results of azo dyes biodegradation tests revealed that strains SNP10, SNP3, and SNP5 were more capable of decolorizing 94-97%, 72.53-73.8, 72.53%, and 71.13-73.5% of Cibacron Brilliant Red EB at concentration 10-20 mg/L within 72 h, respectively. Besides, strain SNP13 was the fastest strain in decolorization of Cibacron Brilliant Red EB with 68% and 59% decolorization activity at 10 and 20 mg/L respectively (24 h). Only strains SNP3 and SNP13 could decolorize 83% and 77% of Terasil Red 3BL-01 (30 mg/L), respectively. For the first time, our research findings illustrated that indigenous rhizospheric bacterial strains isolated from Sparganium erectum L. plants have the potential to apply as an azo dye breakdown tool in textile effluent treatment or other ecosystems.
显示更多 [+] 显示较少 [-]Assessment of Concentration and Distribution of Contaminants Using Magnetic Susceptibility Measurements
2023
Anis, Naushi | Kumar, Arun | Arya, Ajay
Magnetic properties are used throughout the world to measure the concentration of (ferri) magnetic minerals in soil, sediment and dust. These minerals in soil come from a variety of sources, including air-borne particulate pollution, parent rock and paedogenesis. Changes in the content of magnetic minerals, as well as their spatial and vertical distribution in soil profiles are caused by human activity. Magnetic minerals are distinguished by their affinity for other elements found in soil, such as heavy metal. As a result, magnetic susceptibility has been widely used as an approximation of heavy metal contamination in soil. The current study was conducted in a tropical deciduous forest in Central Uttar Pradesh, namely the kukrail reserve forest in Lucknow to assess heavy metal contamination levels caused by various anthropogenic activities and to confirm the utility of using MS surveying in these types of studies. The current study was conducted at two sites viz. agricultural area and forest area because these sites are the most contaminated ones. Significant correlation between heavy metal concentration and magnetic susceptibility with p<0.005 is noticed for Co, Cr, Pb, Zn, Cu and Fe of agricultural area. Similarly in forest area significant correlation exists between Cr, Ni, Pb and Zn. The χLF values show a significant correlation with the concentration of heavy metals except for Cu and Cr in forest area and Pb and Zn in agricultural area. In comparison to the methodologies of chemical analysis, the χLF measurement techniques provide us with lower cost and less time consuming method for identification of possible soil pollution.
显示更多 [+] 显示较少 [-]Physical and Geochemical Characteristics of the Typical Spring’s Mineral Water in the NW of Iran, Case studies Lighvan and Toptapan Springs Mineral Water
2023
Yazdi, Mohamad | Mohammadi, Farhad | Navi, Pedram | Behzadi, Mehrdad
Lighvan hot spring and Toptapan mineral spring are located in the Eastern Azarbaijan, NW of Iran. The host rocks of Lighvan hot spring are dacite, andesite and Quaternary volcanic tuffs. Their main rock forming minerals are quartz, plagioclase, biotite and rarely amphibole. The host rocks of Toptapan mineral water spring are Cretaceous and Jurassic sandstone, shales and carbonate sedimentary rocks. Their main rock forming minerals are quartz, calcite, dolomite and clays. Due to the deposition of mineral water springs, travertine is the main Quaternary sediments around the springs. Water samples were collected from Toptapan mineral spring and Lighvan hot spring in July (dry season). The sampling method was according to standard methods for geochemical analysis. Field parameters such as PH, temperature, and EC were measured in situ, and samples were analyzed by ICP-OEC and ICP-MS in the laboratory of the Geological Survey of Iran. The measuring data showed that pH varies between 6.1 to 6.4. The surface temperature varies from 20.1˚C to 32.8˚C. The concentration of anions and cations in the Piper diagram show calcic bicarbonate type for Toptapan mineral spring and sodic bicarbonate type for Lighvan hot spring respectively. According to Lunglier – Ludwig diagram, the dissolution of carbonate and silicate minerals is the most important factor in increasing calcic cation. The Cl-Li-B diagram shows that the dissolution of sodic minerals and clays and ionic exchange are also the most important factors for increasing sodium in these springs. These data are in agreement to the host rocks, their mineralogy and their chemical composition. Based on the Ca-Mg-K geothermometer diagram, the geothermal reservoir temperature for Lighvan hot spring is 95-100 ˚C with a depth of about 2Km and for Toptapan mineral spring is 65-85 ˚C with a depth of less than 1Km. Also, high concentrations of chlorine show a deep geothermal primary reservoir in the Lighvan hot spring. These geochemical data show that these cold and hot springs are not polluted and not harmful for environmental point of views.
显示更多 [+] 显示较少 [-]Life Cycle Assessment of Crude Oil Processing by Energy Management Approach
2023
Naseri, kioumars | Noorpoor, Alireza | Razavian, Fatemeh | Khoshmaneshzadeh, Behnoush
The first future challenge facing human beings is to supply the world's energy needs. However, energy consumption and resource depletion in industrial processes are significantly increasing. Therefore, life cycle assessment can be an excellent tool to quantify resources and energy consumption in different parts of industrial processes. The combination of process simulation and assessment of process life cycle can be resources & energy consumption in different parts is quantified and can be significantly reduced by optimizing the process, energy wastage. The process stimulation is done by HYSIS software, then by collecting output data, energy and materials flow, life cycle assessment is conducted using SIMAPRO software. According to output of the release list, 1709 items are released into the environment, of which 396, 407, 340 items are released into the air, water, soil, respectively and 556 items are extracted from sources. The most appropriate procedure to assess the life cycle of crude oil processing is Cumulative Energy Demand and Cumulative Exergy Demand energy approach. Based on the first-order analysis, the highest consumption of resources and energy is in the crude oil transmission sector; (Road construction with 44.95 petajoules and transmission pipelines with 19.85 petajoules). Also, regarding the second-order analysis, the highest consumption of resources and energy is related to crude oil production processes with 1.65 petajoules per operation and desalination unit, medium voltage electricity consumption with 0.002194 petajoules and exergy of power lines with 0.00087 petajoules.
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