Rapid extraction of BTEX in water and milk samples based on functionalized multi-walled carbon nanotubes by dispersive homogenized-micro-solid phase extraction.

An advanced synthesis based on the phenylalanine (Phe) and task-specific ionic liquid (TSIL) functionalized on multi-walled carbon nanotubes (Phe/TSIL@MWCNTs), was used to extract benzene, ethylbenzene, toluene, and xylene (BTEX) from cow's milk, powdered milk, and farm water samples. The BTEX was efficiently extracted by ultrasound-assisted dispersive homogenized-micro-solid phase extraction (USA-DH-µ-SPE) between 95.1% and 103.4%. By procedure, 50 mg of Phe/TSIL@MWCNTs was added to 0.2 mL of acetone and injected into 10 mL of the samples. The upper aqueous solution was vacuumed, the vial heated to 80 °C, and the BTEX desorbed in the vial. Then, using a Hamilton syringe, 1-20 µL of gas in the headspace vial was determined by injecting it into the gas chromatography with flame ionization detection (GC-FID). The linear range, LOD, and LOQ for BTEX in milk and water samples were obtained at 0.05-500 µg L-1, 15 ng L-1, and 50 ng L-1, respectively (r = 0.9997, RSD% = 2.27).

The monetary facilities payment for ecosystem services as an approach to restore the Degraded Urmia Lake in Iran.

This study analyzed the potential use of Payment for Ecosystem Services (PES) as a strategy for improving water supply management. This study focused on the Siminehroud Sub-basin due to its high importance to the Basin of Urmia Lake (UL). Siminehroud is the second provider of water (by volume) to Urmia Lake. To evaluate the technical and economic feasibility of a PES scheme, the current land use map was extracted using satellite imagery. In addition, the two algorithms of Support Vector Machines (SVMs) and Maximum Likelihood (ML) are used for Landsat images classification, rather than analyzing the relationship between land use and ecosystem services. Then, the most relevant ecosystem services provided in the region were evaluated using the Benefit Transfer Method. In the last step, by designing and implementing a survey, on the one hand, the local farmers' Willingness to Accept (WTA) cash payments for reducing the area they cultivate, and on the other hand, the farmers' Willingness to Pay (WTP) for managing the water consumption were determined. The results illustrated that the WTA program is more acceptable among the beneficiaries. It is also notable that this program needs very high governmental funding. Furthermore, the results of the program indicate that the land area out of the cultivation cycle will gradually increase while the price of agricultural water will also increase.

An immobilization of aminopropyl trimethoxysilane-phenanthrene carbaldehyde on graphene oxide for toluene extraction and separation in water samples.

A new functionalized Nano graphene with aminopropyl trimethoxysilane-phenanthrene-4-carbaldehyde (NGO@APTMS-PNTCA) as a novel adsorbent was used to extract toluene from water samples by the ultrasound-assisted dispersive solid-phase microextraction procedure (USA-D-SPME). So, 50 mg of NGO@APTMS-PNTCA adsorbent was added to water samples and sonicated for 20 min. After toluene extraction, the NGO@APTMS-PNTCA adsorbent separated from the liquid phase with a Whatman membrane filter (200 nm). Then, the toluene was back-extracted from the adsorbent by 2.0 mL of the acetone/ethanol (1:1, eluent) at 25 °C. Due to the physical properties and structure of toluene, fluorobenzene was used as an internal standard. Finally, the toluene values were measured by a gas chromatography-flame ionization detector (GC-FID). In optimized conditions, the limit of detection (LOD), the working range (WR), and the enrichment factor (EF) were obtained at 2.5 µg L-1, 0.01-1.2 mg L-1, and 9.63, respectively (MRSD% = 3.38). Also, the limit of quantification (LOQ) 10 µg L-1 and extraction recovery of more than 95% was efficiently achieved for toluene. Standard additions of toluene to blank solutions had high recoveries between 95.2% and 104.5% with a relative standard deviation (RSD%) of 0.27-5.2. The absorption capacities of NGO and NGO@APTMS-PNTCA adsorbents for toluene extraction were obtained at 32.8 mg g-1 and 154.9 mg g-1, respectively. The USA-D-SPME method was validated by spiking the standard concentrations of toluene. The proposed method demonstrated relevant and suitable statistical results with high accuracy and precision for toluene extraction by a novel adsorbent synthesis.

Sustainable power generation through decarbonization in the power generation industry.

Due to using fossil energy resources, power generation is the most important factor of pollution and greenhouse gas emissions. Considering the importance of the issue, seven scenarios for decreasing greenhouse gas emissions in the power industry, including the development of renewable energies, energy efficiency in thermal power plants, and decreasing the emission of carbon according to international agreements, and the creation of sustainable power generation systems, were defined and evaluated technically, economically, and environmentally. In the current study, an optimization model for long-term power generation planning was used for two concepts of supply and demand. The results of comparing the scenarios showed that the development of renewable power plants was not solely a suitable and optimal way for decreasing greenhouse gas and carbon emissions. The strategies for improving efficiency in thermal power plants, including the development of combined cycle power plants and the repowering of steam power plants, are more suitable options for implementation, considering the constraints of the problem. Therefore, eliminating the existing circumstances and employing the combined scenario while considering the objectives of the study should be the only strategy for decarbonization in this industry, with the minimum cost and minimum rate of emission. By decreasing the share of thermal power plants, decreasing fuel demand, and increasing the share of renewable power plants to 20%, the combined scenario would decrease pollution and greenhouse gas emissions by up to 77.6 million tons of carbon dioxide, as well as the environmental costs up to 1894.5 million dollars, compared to the basic scenario up to 2030. Moreover, paying attention to the management strategies of a demand concept seems necessary from an economic viewpoint, in addition to other presented strategies.

Application of geostatistical models to identify spatial distribution of groundwater quality parameters.

Groundwater quality management is a priority in arid and semi-arid zones where water is scarce. Leachate from open dumping of municipal solid wastes may threaten groundwater quality. This research aimed at assessing groundwater quality of the aquifer of Shur river basin in Tehran province, Iran. The pollution potential of leachate from a landfill, located at the center of the basin, was estimated to assess its impact on the aquifer. Samples from 38 wells and 2 leachate ponds around the landfill were analyzed for their physico-chemical parameters and heavy metals. Leachate Pollution Index (LPI) and Water Quality Index (WQI) were calculated and multivariate statistical techniques were employed through geostatistical models to predict the spatial variability of groundwater quality and assess its contamination sources. The groundwater quality map was developed by GIS Interface. LPI indicated that leachate from the closed cell (LPI = 36) was more contaminating than that of the active site (LPI = 25). Kriging and cokriging geostatistical interpolation methods were applied to groundwater quality parameters. The best interpolation model was then identified through cross-validation with RMSE and GSD criteria. Cokriging yielded more accurate results than kriging. Spatial distribution maps showed high groundwater contamination and degraded water quality mainly in the central part of the basin, where the landfill was. Also, 293.7 ha of the study area possessed poor and very poor water quality, unsuitable for drinking. This study implicated multiple approaches for groundwater quality assessment and estimated its spatial structure as an effort toward effective groundwater quality management in Shur river basin.

Application of MCAT to provide multi-objective optimization model for municipal waste management system.

Choosing an appropriate municipal waste management method is a very complicated environmental problem in cities. This research introduces an optimization model for waste management in the southwest region of Tehran province. It was developed by a metaheuristic algorithm that was used to minimize the economic and environmental costs. Incineration, composting, recycling and landfilling waste management methods were considered. Three scenarios were developed to determine the optimum allocation of waste to each method such to fulfill the objective of overall minimum of environmental burdens and costs. A multi-objective scenario selection model was implemented by the compromise programming method in MCAT software. Considering the budget limitation and available facilities on site, optimum allocations to recycling, composting, incineration and landfilling methods were obtained as 115,486, 132,094, 71,905 and 45,516 tons/year, respectively. The results of this study indicated that the metaheuristic algorithm in MCAT software was an efficient tool in decision making about waste management systems and thus, it was suggested to municipality managers and regional planning authorities.

New insight into examining the role of financial development in economic growth effect on a composite environmental quality index.

The inclusion of an index, which can be the representative of environmental quality from different aspects, seems to be of paramount significance. This issue is a major challenging one in the economic-environmental literature. This study investigates the role of financial development in economic growth effect on the composite environmental quality index (CEQI) in two groups of selected Organization of the Petroleum Exporting Countries (OPEC) and Organization for Economic Co-operation and Development (OECD) countries. In this regard, System Generalized Method of Moment (SYS-GMM) is applied to fit the research models. According to the findings, in the selected OPEC countries, financial development reinforces negative impacts of economic growth on environmental quality. In the selected OECD countries, economic growth has negative effect on the environmental quality and financial development weakens this effect. The effect of financial development on the CEQI is respectively negative and positive in OPEC and OECD countries. Moreover, in both groups of selected countries, energy consumption and economic growth have a negative impact on the CEQI; nonetheless, trade openness has a positive effect. Accordingly, some policy suggestions and new recommendations are presented for future studies, which would contribute to the better implementation of economic-environmental policies. Graphical abstract.

Investigating marginal effect of economic growth on environmental quality based on six environmental indicators: does financial development have a determinative role in strengthening or weakening this effect?

Given the complexity of the correlation of economic growth with financial development, and their interactive impacts on environmental quality, this study attempted to present new insights into indecisive outcomes from the contribution of financial development in determining the impressionability of environmental indicators under economic growth conditions. Previous studies only employed a single environmental indicator for analyzing the correlation between economic factors and environmental quality. However, six environmental indicators are adopted in this study to evaluate environmental quality and to reach major goals of this research. To this end, using 2-stage system generalized technique of moment estimator, the association of economic growth, energy consumption, financial development, environmental indicators, and trade openness is determined in selected OPEC countries for years 2010 to 2019. Findings indicated that accompanied by the effects of economic growth on any EFI, ANS, PN, and EPI variables, the financial development enhances such effect. This is while, the financial development would weaken the economic growth effect on the ESI variable. Regarding EVI, no significant association was observed. Regarding to ESI, EPI, and PN, trade openness applies a significantly positive impact on environmental quality; on the other hand, it has positive role in environmental degradation based on EFI and ANS. This is while, according to the EVI variable, trade openness has not meaningful impact on environmental status. Finally, energy use has significant and positive effects on environmental degradation in each of environmental indicators. However, this variable has not shown significant impact on EPI and ANS. Alternatively, findings indicated that financial development can be considered an important and key variable in improvement of the environmental quality due to the moderating role it plays relative to the negative economic growth effect on the environmental quality. At the end of this paper, some limitations are presented, and some suggestions for further studies are provided as well.

Scenarios evaluation on the greenhouse gases emission reduction potential in Iran's thermal power plants based on the LEAP model.

Over the past few years, the pace of fossil fuel consumption has witnessed an accelerating trend across the world which has been really noticeable especially for the power generation sector. With regard to its global importance, the environment must be also preserved and emissions of pollutants and greenhouse gases (GHGs) as well as environmental costs need to be moderated. Given the urgency of energy preservation and environmental issues, the process of electricity generation should be evaluated. Accordingly, elimination of conditions along with prediction of energy consumption and pollutant emissions have been performed through energy simulation and modeling software tools, e.g., Long-range Energy Alternatives Planning System (LEAP). The energy consumption in thermal power plants for 2035 is estimated to be 209.7, 153.5, and 132.0 Bcm respectively for Reference (REF), Efficiency based on 5-Year National Development Plan (E5P), and Efficiency similar to UK (EUK) scenarios using efficiency improvement scenario of thermal power plants in Iran. GHG emissions for 2035 are thus predicted by 456.8 MtCO2-eq for the REF scenario, and 332.6 and 285.1 MtCO2-eq for the E5P and the EUK ones, respectively. Environmental costs for electricity generation system will also diminish via applying scenarios in this sector and its least amount, that is, US$835.8 million is related to the EUK scenario. Accomplishing goals such as better preservation of fossil resources and the environment will be consequently facilitated through improved efficiency and effectiveness of consumption of energy resources. To meet the objectives of environmental preservation, it is suggested to completely implement development plans and also make attempts to promote the technology of thermal power plants in Iran similar to that in developed countries. This study also compares the findings with those reported in recently published investigations.