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Do affluent nations value a clean environment and preserve it? Evaluating the N-shaped environmental Kuznets curve Full text
2022
Shaheen, Fiza | Zaman, Khalid | Lodhi, Muhammad Saeed | Nassani, Abdelmohsen A. | Haffar, Mohamed | Abro, Muhammad Moinuddin Qazi
Since industrialization, the world has been under great strain from rising temperatures. Economies work hard to boost economic growth by sacrificing natural surroundings that are degrading owing to increased carbon emissions from unsustainable production and consumption. The race-to-the-bottom strategy is seen in different parts of the globalized world, corroborating the pollution haven concept and energy-related emissions. The study assumed that once affluent nations reached a particular economic level, they would concentrate on environmental reforms to safeguard environmental and natural resources. The study built a model of the emissions-growth nexus by controlling inward FDI, information and communication technology, research and development expenditures, and renewable energy using aggregated data from high-income nations from 1976 to 2019. The study verified the N-shaped environmental Kuznets curve using a three-degree polynomial factor of per capita income. On the other hand, inward FDI was assessed as having the potential to support the pollution haven hypothesis (PHH) by increasing carbon emissions. The data show that the square and cubic forms of per capita income have a significant negative and positive effect on carbon emissions in the long run, corroborating the short-peak V-shaped EKC hypothesis. However, the N-shaped EKC hypothesis between income and emissions is verified in the short run. The PHH confirmed that more inward FDI is associated with higher long-term carbon emissions. For decreasing global carbon emissions and unclean production, stringent and incentive-based regulations are preferable.
Show more [+] Less [-]Removal of Cd2+ from water containing Ca2+ and Mg2+ using titanate nanotubes modified by carbon Full text
2022
Wu, Mingda | Lu, Linghong | Zhou, Tao | Ma, Yi | Weng, Zhengsong
Calcium and magnesium ions usually exist in natural water. When Cd²⁺ is removed from water by adsorption, it will be inhibited by these two ions. Titanate nanotubes (TNTs) have an effective adsorption capacity for Cd²⁺ due to extraordinary ion exchange property. However, TNTs also adsorb Ca²⁺ and Mg²⁺ in water. In this study, carbon-modified TNT (TNT/C) and TNT/C further treated with acid (TNT/HC) were synthesized by hydrothermal synthesis. The transmission electron microscope (TEM) images show that TNT/C or TNT/HC still keep nanotube morphology. The experimental results show the order of adsorption amount to Cd²⁺ is TNT (171.56 mg/g) > TNT/C (166 mg/g) > TNT/HC (159.88 mg/g) when there is no Ca²⁺ or Mg²⁺. But when there is 0.1 M Ca²⁺ or Mg²⁺ in the water, the order of Cd²⁺ adsorption capacity becomes TNT/HC (44.28, 49.04 mg/g) > TNT/C (58.84, 69.32 mg/g) > TNT (65.52, 70.6 mg/g). It indicates that the surface carbon modification can alleviate the hindrance of Ca²⁺ or Mg²⁺ to Cd²⁺ removal. This is because the carbon on the surface of TNT captured part of Ca²⁺ or Mg²⁺; it made more Cd²⁺ be successfully absorbed by TNT through ion exchange. This mechanism was confirmed by the X-ray photoelectron spectroscopy (XPS) spectra analysis. The results of this paper can provide ideas for the adsorption and removal of Cd²⁺ in water in the presence of Ca²⁺ or Mg²⁺.
Show more [+] Less [-]CO2 emissions, income inequality, and country risk: some international evidence Full text
2022
Guo, Yawei | You, Wanhai | Lee, Chien-Chiang
This research explores the effects of income inequality and country risk on CO₂ emissions and examines whether the effects change across countries with different development stages or income levels. A new panel quantile regression approach is used to conduct a comprehensive analysis of the impacts of affecting factors on CO₂ emissions at various quantiles, while addressing econometric challenges such as endogeneity and heterogeneity. From a global perspective, we can conclude that the marginal impact of inequality on emissions drops constantly with decreasing country risk at 10th to 50th quantiles, which even performs negative, whereas at the other quantiles, the marginal impact of inequality always remains negative. When we focus on the different income groups, the nexus of inequality emissions is negative first and then positive with decrease of country risk in low-income countries but shows no significant in low-middle- and upper-middle-income countries. Additionally, we validate the detrimental impact of income inequality in upper-income countries. Besides, country risk adversely moderates the nexus of inequality and emissions in low- and upper-income countries. Empirical results confirm that the nexus of inequality emissions lies in country risk, income level, and existing emission degree. These findings provide some important recommendations for policy-makers.
Show more [+] Less [-]Construction and evaluation of a system to measure the coordinated development of the ecological environment and the economy of the construction industry Full text
2022
Shen, Yue | Ren, Yixin
Based on the core concept of coordinated development of ecological environment and economy, the five-dimensional evaluation indexes including scale expansion, sustained growth, innovation development, green development and open development are constructed. In this paper, the combined weight model of CRITIC-entropy weight method TOPSIS model are used to comprehensively evaluate the coordinated development of ecological environment and economy of construction industry in China’s provinces, municipalities and autonomous regions (except Xizang, Hong Kong, Macao and Taiwan) from 2004 to 2017. The results show that: (1) Open development and innovative development are the main factors affecting the coordinated development of ecological environment and economy of construction industry. (2) From 2004 to 2017, the coordinated development level of ecological environment and economy of construction industry in 30 provinces, municipalities and autonomous regions in China has a growing trend. However, at present, the level of coordinated development of the ecological environment and the economy of the construction industry in China is generally low. (3) The level of coordinated development between ecological environment and economy of construction industry in eastern China, northeast China, central China and western China is obviously different, showing a spatial distribution pattern of “the level of development from east to west”. On this basis, corresponding policy suggestions are put forward in order to provide reference for promoting the coordinated development of ecological environment and economy in China’s construction industry.
Show more [+] Less [-]Exploring the potential of vermicompost as a sustainable strategy in circular economy: improving plants’ bioactive properties and boosting agricultural yield and quality Full text
2022
Kamar Zaman, Amira Maisarah | Yaacob, Jamilah Syafawati
Consumption of natural resources and waste generation continues to rise as the human population increases. Ever since the industrial revolution, consumers have been adopting a linear economy model based on the ‘take-make-dispose’ approach. Raw materials are extracted to be converted into products and finally discarded as wastes. Consequently, this practice is unsustainable because it causes a massive increase in waste production. The root problems of the linear system can be addressed by transitioning to a circular economy. Circular economy is an economic model in which wastes from one product are recycled and used as resources for other processes. This literature review discovers the potential of vermicompost as a sustainable strategy in circular economy and highlights the benefits of vermicompost in ensuring food security, particularly in improving agricultural yield and quality, as well as boosting crop’s nutritional quality. Vermicompost has the potential to be used in a variety of ways in the circular economy, including for agricultural sustainability, managing waste, pollutant remediation, biogas production and animal feed production. The recycling of organic wastes to produce vermicompost can benefit both the consumers and environment, thus paving the way towards a more sustainable agriculture for the future.
Show more [+] Less [-]Wild type and variants of SARS-COV-2 in Parisian sewage: presence in raw water and through processes in wastewater treatment plants Full text
2022
Viveros, Melissa Lopez | Azimi, Sam | Pichon, Elodie | Roose-Amsaleg, Céline | Bize, Ariane | Durandet, Franz | Rocher, Vincent
Wild type and variants of SARS-COV-2 in Parisian sewage: presence in raw water and through processes in wastewater treatment plants Full text
2022
Viveros, Melissa Lopez | Azimi, Sam | Pichon, Elodie | Roose-Amsaleg, Céline | Bize, Ariane | Durandet, Franz | Rocher, Vincent
The presence of SARS-CoV-2 RNA has been extensively reported at the influent of wastewater treatment plants (WWTPs) worldwide, and its monitoring has been proposed as a potential surveillance tool to early alert of epidemic outbreaks. However, the fate of the SARS-CoV-2 RNA in the treatment process of WWTP has not been widely studied yet; therefore, in this study, we aimed to evaluate the efficiency of treatment processes in reducing SARS-CoV-2 RNA levels in wastewater. The treatment process of three WWTPs of the Parisian area in France was monitored on six different weeks over a period of 2 months (from April 14 to June 9, 2021). SARS-CoV-2 RNA copies were detected using digital polymerase chain reaction (dPCR). Investigation on the presence of variants of concern (Del69-70, E484K, and L452R) was also performed. Additionally, SARS-CoV-2 RNA loads in the WWTPs influents were expressed as the viral concentration in per population equivalent (PE) and showed a good correlation with French public health indicators (incidence rate). SARS-CoV-2 RNA loads were notably reduced along the water treatment lines of the three WWTPs studied (2.5–3.4 log reduction). Finally, very low SARS-CoV-2 RNA loads were detected in effluents (non-detected in over half of the samples) which indicated that the potential risk of the release of wastewater effluents to the environment is probably insignificant, in the case of WWTPs enabling an efficient biological removal of nitrogen.
Show more [+] Less [-]Wild type and variants of SARS-COV-2 in Parisian sewage: presence in raw water and through processes in wastewater treatment plants Full text
2022
López Viveros, Melissa | Azimi, Sam | Pichon, Elodie | Roose-Amsaleg, C. | Bize, Ariane | Durandet, Franz | Rocher, Vincent | SIAAP - Direction du Développement et de la Prospective ; Syndicat interdépartemental pour l'assainissement de l'agglomération parisienne (SIAAP) | Ecosystèmes, biodiversité, évolution [Rennes] (ECOBIO) ; Université de Rennes (UR)-Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des sciences de l'environnement de Rennes (OSERen) ; Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rennes 2 (UR2)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Procédés biotechnologiques au service de l'environnement (UR PROSE) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | IAGE Company
International audience | The presence of SARS-CoV-2 RNA has been extensively reported at the influent of wastewater treatment plants (WWTPs) worldwide, and its monitoring has been proposed as a potential surveillance tool to early alert of epidemic outbreaks. However, the fate of the SARS-CoV-2 RNA in the treatment process of WWTP has not been widely studied yet; therefore, in this study, we aimed to evaluate the efficiency of treatment processes in reducing SARS-CoV-2 RNA levels in wastewater. The treatment process of three WWTPs of the Parisian area in France was monitored on six different weeks over a period of 2 months (from April 14 to June 9, 2021). SARS-CoV-2 RNA copies were detected using digital polymerase chain reaction (dPCR). Investigation on the presence of variants of concern (Del69-70, E484K, and L452R) was also performed. Additionally, SARS-CoV-2 RNA loads in the WWTPs influents were expressed as the viral concentration in per population equivalent (PE) and showed a good correlation with French public health indicators (incidence rate). SARS-CoV-2 RNA loads were notably reduced along the water treatment lines of the three WWTPs studied (2.5-3.4 log reduction). Finally, very low SARS-CoV-2 RNA loads were detected in effluents (non-detected in over half of the samples) which indicated that the potential risk of the release of wastewater effluents to the environment is probably insignificant, in the case of WWTPs enabling an efficient biological removal of nitrogen.
Show more [+] Less [-]Allocation of carbon emission quotas among provinces in China: efficiency, fairness and balanced allocation Full text
2022
Zhan, Dongbao
This paper constructs the ZSG-SBM model, comprehensive fairness allocation model, and balance allocation model from the perspectives of efficiency, fairness, and balance. Making use of the actual input-output data of China’s provincial economic system in 2019, and the above three models to study the reasonable scheme of China’s provincial carbon emission quota allocation in 2019. The results show that ZSG efficiency allocation can significantly improve the carbon emission efficiency of inefficient provinces, and the carbon emissions of inefficient provinces after allocation reach the efficiency frontier. The carbon emission quota of 16 provinces which located in the central and western regions of China with underdeveloped economy and relatively low carbon emission efficiency need to be decreased, while the eastern coastal provinces with more developed economy and high carbon emission efficiency in China should increase their carbon emission quota. On the one hand, comprehensive fairness allocation reduces the carbon emission reduction target constraints of economically underdeveloped provinces; on the other hand, it strengthens the carbon emission reduction target constraints of low-carbon technology backward provinces. As a result, the carbon emission quota of economically developed provinces and provinces with high carbon intensity per unit GDP is reduced in this method. The result of balancing efficiency and fairness lies between ZSG efficiency allocation and comprehensive fairness allocation. In order to alleviate the huge pressure on the emission reduction of provinces with low actual carbon emission efficiency under the ZSG efficiency allocation mode, the Chinese government can gradually increase the weight of ZSG efficiency allocation results, and finally adopt a complete ZSG efficiency allocation scheme in the carbon peak year to realize the transformation of low-carbon economy.
Show more [+] Less [-]The environmental Kuznets curve for Turkish provinces: a spatial panel data approach Full text
2022
Karahasan, Burhan Can | Pınar, Mehmet
This paper aims to test the existence of the environmental Kuznets curve (EKC) hypothesis using SO2 measurements in Turkish provinces between 2004 and 2019. The existing studies concerning the EKC hypothesis for Turkey either use a country-level analysis or panel data techniques covering provincial data that do not account for the spatial dimension. To account for the spatial dependence and overcome the biases resulting from the existence of such spatial spillovers, this paper combines the traditional panel data methodology with the recent advances in spatial econometrics. Our findings confirm the presence of a non-linear link between regional economic prospects and environmental degradation. However, unlike the core expectations of the EKC hypothesis, our results demonstrate a U-shaped relationship between economic development and SO2 levels. Moreover, these findings are robust to the inclusion of a spatial battery which highlights the existence of regional spillovers. Overall, our results show that the post-2000 epoch calls for a different action plan to mitigate the rising impact of environmental degradation in Turkey.
Show more [+] Less [-]Valorization of rubberwood sawdust and sewage sludge by pyrolysis and co-pyrolysis using agitated bed reactor for producing biofuel or value-added products Full text
2022
Ali, Liaqat | Palamanit, Arkom | Techato, Kuaanan | Baloch, Khurshid Ahmed | Jutidamrongphan, Warangkana
This study investigated experimentally pyrolysis of rubberwood sawdust (RWS), sewage sludge (SS), and their blends (25:75, 50:50, and 75:25 by weight) in an agitated bed pyrolysis reactor. The yields and characteristics of liquid product and biochar were determined for pyrolysis at 450, 500, and 550 °C and were affected both by temperature and feedstock type. The liquid and biochar yields were in the ranges 27.30–52.42 and 21.43–49.66 (wt%). Pyrolysis of RWS at 550 °C provided the highest liquid yield, while SS gave a high biochar yield. Co-pyrolysis of SS with RWS improved yield and quality of liquid and biochar products. The liquid product had 57.54–70.70 wt% of water and a low hydrocarbon content. The higher heating value (HHV) of water-free liquid product was 14.73–22.45 MJ/kg. The major compounds of liquid product included acetic acid, 2-propanone, 1-hydroxy, and phenols according to GC-MS. The biochar from RWS had a high carbon content (83.37 wt%) and a high HHV (33.57 MJ/kg), while SS biochar was mainly ash (67.62 wt%) with low carbon content. The SS biochar also had high contents of Si, Ca, Fe, K, and Mg as determined by XRF. Co-pyrolysis of SS with RWS improved the biochar by increasing its carbon content and reducing ash and inorganic elements. The surface of RWS biochar was more porous, while SS biochar had the larger specific surface according to SEM and BET. Based on these results, co-pyrolysis of 75:25 feedstock mix is recommended for further studies on applications of liquid product and biochar.
Show more [+] Less [-]Effect of brominated flame retardant on the pyrolysis products of polymers originating in WEEE Full text
2022
Charitopoulou, Maria Anna | Papadopoulou, Lambrini | Achilias, Dimitriοs S.
Chemical recycling is an environmentally friendly method, which is often used for the recycling of plastics included in waste electric and electronic equipment (WEEE), since fuels and secondary valuable materials can be produced. Brominated flame retardants (BFRs) are usually added into these plastics to reduce their flammability; but they are toxic substances. The aim of this work is to examine the thermal behaviour and the products obtained after pyrolysis of polymer blends that consist of acrylonitrile-butadiene-styrene (ABS), high-impact polystyrene (HIPS), polycarbonate (PC) and polypropylene (PP) with composition that simulates real WEEE, in the absence and presence of a common BFR, tetrabromobisphenol A (TBBPA), in order to investigate its effect on pyrolysis products. Blends were prepared via the solvent casting method and the melt-mixing in an extruder; it was revealed that the latter method may be a better choice for blends preparation, since it did not affect the products obtained. The chemical structure of each polymeric blend was identified by Fourier transform infrared spectroscopy (FTIR). Thermal degradation of the blends was evaluated by thermogravimetric (TG) experiments performed using a thermal analyser (TGA) and a pyrolyser for evolved gas analysis (EGA). It was observed that blends had a similar behaviour during their thermal degradation; and in most cases, they followed a one-step mechanism. Pyrolysis products were identified by the pyrolyser combined with a gas chromatographer/mass spectrometer (GC/MS), and comprised various useful compounds, such as monomers, aromatic hydrocarbons and phenolic compounds that could be used as chemical feedstock. Furthermore, it was found that TBBPA affected products distribution by enhancing the formation of phenolic compounds and on the other hand by resulting in brominated compounds, such as dibromophenol.
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