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One-pot synthesis of Cr(III)-incorporated Zr(IV) oxide for fluoride remediation: a lab to field performance evaluation study Full text
2020
Kanrar, Sarat | Ghosh, Abir | Ghosh, Ayan | Mondal, Arpan | Sadhukhan, Mriganka | Ghosh, Uday Chand | Sasikumar, Palani
A low-cost Cr(III)-incorporated Zr(IV) bimetallic oxide (CZ) was synthesized by simple chemical precipitation method for removal of fluoride from contaminated water. The physicochemical properties of CZ before and after fluoride removal were established with several instrumental techniques such as TEM with elemental mapping, SEM with EDX, XRD, IR, XPS, zeta potential measurement, etc. Batch adsorption technique were carried out to understand the factors affecting fluoride adsorption, such as effects of initial pH, adsorbent dose, co-occurring ions, contact time, and temperature. The maximum adsorption capacity observed at pH between 5 and 7. The fluoride adsorption processes on CZ obeyed the pseudo-second-order rate equations and both Freundlich and DR isotherm models. The maximum adsorption capacity of 90.67 mg g⁻¹ was obtained. The thermodynamic parameters ΔH⁰ (positive), ΔS⁰ (positive), and ΔG⁰ (negative) indicating the fluoride sorption system was endothermic, spontaneous, and feasible. The CZ also successfully used as fluoride adsorbent for real field contaminated water collected from the Machatora district, Bankura, West Bengal, India. Graphical abstract Schematic representation of CZ synthesis and its application for lab as well as field water purification purpose.
Show more [+] Less [-]Correction to: Intelligent-activated carbon prepared from pistachio shells precursor for effective adsorption of heavy metals from industrial waste of copper mine Full text
2020
Nejadshafiee, Vajihe | Islami, Mohammad Reza
The original publication of this paper contains a mistake.
Show more [+] Less [-]Valuing urban air quality: a hedonic price analysis in Beijing, China Full text
2020
Mei, Yingdan | Gao, Li | Zhang, Jiawei | Wang, Jiahao
Although Chinese government has implemented a series of laws, regulations, and policies to deal with air pollutants, air pollution is still one of the biggest concerns in China. Most of the cities in China suffered from extremely high air pollution levels and cannot meet the national air quality standards. In this study, we attempt to measure individuals’ average marginal willingness to pay (MWTP) in Beijing with the hedonic price model. We combine an extensive housing transaction dataset with emission data of six air pollutants from 2013 to 2016 in Beijing, China. When estimating the hedonic price function, we apply both ordinary least squares (OLS) and panel model with various fixed effects to better control for unobservables. The empirical results reveal that the concentrations of CO, NO₂, PM₂.₅, and PM₁₀ are significantly negatively correlated with housing prices. However, we found an insignificant relationship with the concentration of SO₂ and the concentration of O₃ appears to positively increase the housing values. Policy implications based on these results were also discussed.
Show more [+] Less [-]Photocatalytic degradation of a typical neonicotinoid insecticide: nitenpyrum by ZnO nanoparticles under solar irradiation Full text
2020
Islam, Jahida Binte | Furukawa, Mai | Tateishi, Ikki | Katsumata, Hideyuki | Kaneco, Satoshi
The photodegradation and mineralization of the nitenpyrum [(E)-N-(6-chloro-3-pyridylmethyl)-N-ethyl-N′-methyl-2-nitrovinylidenediamine], which is one of the most popular neonicotinoid insecticides, were conducted in the presence of ZnO photocatalyst under solar irradiation. An initial nitenpyrum concentration of 10 ppm was completely degraded in the presence of ZnO after 30 min irradiation, while only 70% degradation was observed in the absence of ZnO. The effect of different parameters, for example, amount of ZnO, initial pH, light intensity, reaction temperature, and irradiation time, on the photocatalytic degradation of nitenpyrum was also evaluated. The drop of total organic carbon (TOC) as a consequence of mineralization of nitenpyrum was observed during the photocatalytic process. The kinetics of photocatalytic degradation followed a pseudo-first order law according to Langmuir-Hinshelwood model, and the rate constant is 0.140 min⁻¹. CO₂, chloride, and nitrate ions were observed as the end-products after completing degradation of nitenpyrum. The four kinds of intermediate products were identified by GC-MS during the decomposition of nitenpyrum. In order to investigate the degradation pathway of nitenpyrum, the point charge and frontier electron density at each atom on the molecule were determined using molecular orbital (MO) stimulation. The degradation mechanism was proposed, based on the identified intermediates. The solar photocatalytic degradation method can become an effective technique for the treatment of nitenpyrum-polluted water.
Show more [+] Less [-]Spirulina platensis as renewable accumulator for heavy metals accumulation from multi-element synthetic effluents Full text
2020
Cepoi, Liliana | Zinicovscaia, Inga | Rudi, Ludmila | Chiriac, Tatiana | Miscu, Vera | Djur, Svetlana | Strelkova, Ludmila | Grozdov, Dmitrii
Metal accumulation by Spirulina platensis from synthetic effluents with the following chemical composition: Cr/Fe, Cr/Fe/Ni, Cr/Fe/Ni/Zn, and Cr/Fe/Ni/Zn/Cu during repeated cultivation cycle was investigated. Metal ions in different concentrations were added to the culture medium at the exponential and stationary phases of biomass growth and their uptake by biomass was traced using neutron activation analysis. The effect of metal ions on biomass and main biochemical components (proteins, carbohydrates, lipids, phycobilins, and β-carotene) was monitored. S. platensis keeps high metal accumulation capacity during 2–3 cultivation cycles, while the metal ions were added in the stationary phase of its growth. By adding metals in the exponential phase of growth in the following concentrations: 10 mg/L of chromium (VI), 5 mg/L of iron, 2 mg/L of zinc, nickel, and copper, Spirulina platensis acted as renewable accumulator only in Cr/Fe system. It maintained the accumulation capacity during three cultivation cycles when exposed to lower concentrations of metal ions. Its ability to accumulate metal ions during several cultivation cycles was ensured by the maintenance of the optimal level of proteins and lipid in biomass.
Show more [+] Less [-]Assessment of renewable energy supply for green ports with a case study Full text
2020
Sadek, Ibrahim | Elgohary, Mohamed
Seaports are considered one of the sources involved in the deterioration of the maritime environment due to the excessive amount of exhaust gases emitted from their activities. The majority of seaports depend on the national electric grid as a source of power for the domestic and ships’ electric demands. This paper discusses the possibility of shifting ports from relying on the national grid electricity to green power-based ports. Offshore wind turbines and fuel cell units appear as two typical promising clean energy sources for ports. As a case study, the paper investigates the prospect of converting Alexandria Port in Egypt to be an eco-friendly port with the study of technical, logistic, and financial requirements. The results show that the fuel cell, followed by a combined system of wind turbines and fuel cells, is the best choice regarding electricity production unit cost by 0.101 and 0.107 $/kWh, respectively. Furthermore, using fuel cells and offshore wind turbine as a green power concept will achieve a reduction in emissions’ quantity of CO₂, NOx, and CO emissions by 80,441, 20,814, and 133,025 ton per year, respectively. Finally, the paper highlights the role that renewable energy can play when supplying Alexandria Port with green energy to lift the burden on the government in supporting the electricity, with a possibility of achieving a profit from 3.85 to 22.31% of the annual electricity cost compared with the international prices.
Show more [+] Less [-]Influence of climate on energy consumption and CO2 emissions: the case of Spain Full text
2020
Zarco-Soto, Irene M. | Zarco-Periñán, Pedro J. | Sánchez-Durán, Rafael
Influence of climate on energy consumption and CO2 emissions: the case of Spain Full text
2020
Zarco-Soto, Irene M. | Zarco-Periñán, Pedro J. | Sánchez-Durán, Rafael
This paper presents a methodology that allows for calculating the thermal and electric energy consumption together with CO₂ emissions of cities by inhabitant and household based on climate, only making use of publicly available data. With this aim, climate was analysed and cities were classified based on it. The analysis of those cities’ energy consumption and CO₂ emissions allowed for drawing conclusions. Once aware of the climate zones in which energy consumption and emissions are higher, these mentioned conclusions could help to take further actions. An index has been defined to facilitate this analysis. This paper shows the case of Spain for illustrative purposes. This type of study has been carried out in some detail in many countries, but not in Spain yet. This paper tries as well to fill the existing gaps in studies that relate climate to thermal and electric energy consumption. For this purpose, it analyses the 145 cities in Spain that have more than 50,000 inhabitants. Knowing all this is essential in all regions and countries. It will allow for taking proper actions for promoting the energy saving and the use of alternative energy sources that reduce CO₂ emissions. According to the study carried out in this paper, the extremer the climate of a city is, the higher the thermal energy consumption is. This consumption decreases in softer climates. However, electric energy consumption is similar in all cities independent of the climate they have. With regard to CO₂ emissions, it was calculated that the higher the energy consumption of a city is, the higher these emissions are.
Show more [+] Less [-]Influence of climate on energy consumption and CO2 emissions: the case of Spain
Gammarid exposure to pyriproxyfen and/or cadmium: what effects on the methylfarnesoate signalling pathway? Full text
2020
Gammarid exposure to pyriproxyfen and/or cadmium: what effects on the methylfarnesoate signalling pathway? Full text
2020
Due to expected changes in climate, it is predicted that disease-carrying mosquitoes will expand their geographical range, resulting in increased use of insect growth regulators (IGRs) to face their proliferation. Among IGRs, pyriproxyfen (PXF) is widely used and has been shown to prevent larvae from developing into adults, rendering them unable to reproduce. However, because of the similarity of crustacean and insect endocrine systems, PXF could also impact aquatic crustaceans. In addition, when spreading in the environment, PXF is found in a mixture with other pollutants such as metallic trace elements, which could alter its effect. Consequently, the present work was devoted to analysing the effects of PXF on the methylfarnesoate (MF) hormonal pathway of the freshwater amphipod Gammarus pulex, as well as its combined binary effects with cadmium (Cd), by measuring MF concentration, as well as the relative transcriptional expression of the farnesoic acid O-methyltransferase (FAMeT) (enzyme limiting the MF production), the methoprene-tolerant receptor (Met), and the broad-complex (BrC) as a transcription factor. Results revealed that single exposures to PXF or Cd have mainly overexpressed FAMeT, Met, and BrC but did not significantly affect MF concentration. Conversely, the mixture exposures seemed to suppress these effects and even achieve antagonistic effects. This work confirmed that PXF single exposure could impact non-target organisms such as amphipods through changes in hormonal pathways of MF. In the same way, it highlighted that Cd could also impair the endocrine system of exposed organisms. However, antagonistic effects have been observed in exposure to mixtures, suggesting different long-term consequences on the growth of amphipods under realistic exposure conditions.
Show more [+] Less [-]Gammarid exposure to pyriproxyfen and/or cadmium: what effects on the methylfarnesoate signalling pathway? Full text
2020
Jaegers, Jeremy | Gismondi, Eric
Due to expected changes in climate, it is predicted that disease-carrying mosquitoes will expand their geographical range,resulting in increased use of insect growth regulators (IGRs) to face their proliferation. Among IGRs, pyriproxyfen (PXF) iswidely used and has been shown to prevent larvae from developing into adults, rendering them unable to reproduce. However, because of the similarity of crustacean and insect endocrine systems, PXF could also impact aquatic crustaceans. In addition, when spreading in the environment, PXF is found in a mixture with other pollutants such as metallic trace elements, which could alter its effect. Consequently, the present work was devoted to analysing the effects of PXF on the methylfarnesoate (MF) hormonal pathway of the freshwater amphipod Gammarus pulex, as well as its combined binary effects with cadmium (Cd), by measuring MF concentration, as well as the relative transcriptional expression of the farnesoic acid O-methyltransferase (FAMeT) (enzyme limiting the MF production), the methoprene-tolerant receptor (Met), and the broad-complex (BrC) as a transcription factor. Results revealed that single exposures to PXF or Cd have mainly overexpressed FAMeT, Met, and BrC but did not significantly affect MF concentration. Conversely, the mixture exposures seemed to suppress these effects and even achieve antagonistic effects. This work confirmed that PXF single exposure could impact non-target organisms such as amphipods through changes in hormonal pathways of MF. In the same way, it highlighted that Cd could also impair the endocrine system of exposed organisms. However, antagonistic effects have been observed in exposure to mixtures, suggesting different long-term consequences on the growth of amphipods under realistic exposure conditions.
Show more [+] Less [-]Oxythermal window drastically constraints the survival and development of European sturgeon early life phases Full text
2020
Delage, Nicolas | Couturier, Blandine | Jatteau, Philippe | Larcher, Thibaut | Ledevin, Mireille | Goubin, Hélicia | Cachot, Jérôme | Rochard, Eric
Oxythermal window drastically constraints the survival and development of European sturgeon early life phases Full text
2020
Delage, Nicolas | Couturier, Blandine | Jatteau, Philippe | Larcher, Thibaut | Ledevin, Mireille | Goubin, Hélicia | Cachot, Jérôme | Rochard, Eric
European sturgeon Acipenser sturio is an anadromous fish species being classified “critically endangered” with only one remaining population in the Gironde-Garonne-Dordogne basin (France). In the global warming context, this paper aims to determine the sensitivity of A. sturio early life phases to temperature and oxygen saturation. Embryos were experimentally exposed to a combination of temperature (12 to 30 °C) and oxygen (30 to 90% O₂ saturation) conditions. Lethal and sublethal effects were evaluated using embryonic mortality, hatching success, malformation rate, yolk sac resorption, tissue development and swimming speed. Embryonic survival peaked at 20 °C and no survival was recorded at 30 °C regardless of the associated oxygen saturation. No hatching occurred at 50% O₂ sat or below regardless of temperature. Malformation frequency appeared to be minimum at 20 °C and 90% O₂ sat. Swimming speed peaked at 16 °C. The temperature optimum of early life phases of A. sturio was determined to be close to 20 °C. Its upper tolerance limit is between 26 and 30 °C and its lower tolerance limit is below 12 °C. Oxygen depletion induces sublethal effects at 70% O₂ sat and lethal effects at 50% O₂ sat. Within the spawning period in the Gironde-Garonne-Dordogne basin, we identified yearly favourable oxythermal windows. Consequences of climate change would depend of the phenological adaptation of the species for its spawning period.
Show more [+] Less [-]Oxythermal window drastically constraints the survival and development of European sturgeon early life phases
Ecological assessment of groundwater ecosystems disturbed by recharge systems using organic matter quality, biofilm characteristics, and bacterial diversity Full text
2020
Voisin, Jérémy | Cournoyer, Benoit | Marjolet, Laurence | Vienney, Antonin | Mermillod-Blondin, Florian
Ecological assessment of groundwater ecosystems disturbed by recharge systems using organic matter quality, biofilm characteristics, and bacterial diversity Full text
2020
Voisin, Jérémy | Cournoyer, Benoit | Marjolet, Laurence | Vienney, Antonin | Mermillod-Blondin, Florian
Recharge of aquifers by urban stormwater may trigger significant ecological changes that can be detrimental to the biodiversity and functioning of groundwater ecosystems. Here, the effects of aquifer recharge (AR) on three levels of parameters were investigated: dissolved organic carbon (DOC) quantity and quality, global biofilm characteristics, and diversity changes of bacterial communities. As DOC enrichment by AR can be mitigated by vadose zone (VZ) thickness, three AR sites with thin VZ (< 3 m) and three sites with thick VZ (> 10 m) were selected. For each AR site, clay beads were incubated over a 10-day-long rainy period through wells in recharged and non-recharged groundwaters. Total proteins, dehydrogenase, and hydrolytic activities were monitored from clay beads to assess biofilm development. Bacterial richness on beads was estimated by 16S rRNA-based metabarcoding. AR was found to significantly increase DOC and biodegradable DOC (BDOC) concentrations, biofilm development, and bacterial richness especially in sites with thin VZ. VZ thickness was inversely related to microbial growth indicators and bacterial richness in groundwater, through a control of DOC availability. The proportion of Bacteroidetes 16S rRNA gene reads was higher in recharged groundwater than in non-recharged groundwater, suggesting that this phylum could be used as an indicator of DOC enrichment associated with AR. Quantitative PCR assays for Bacteroides DNA confirmed these trends and showed an enrichment of this bacterial group in DOC-rich aquifer waters. The positive linear relationships between BDOC concentrations and biofilm variables highlighted a strong C-limitation of groundwater impacting bacterial species sorting and activity.
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