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Assessing enablers of e-waste management in circular economy using DEMATEL method: An Indian perspective Полный текст
2020
Śarmā, Manu | Joshi, Sudhanshu | Ashwani Kumar,
With increasing population, excessive use of electrical and electronic products and extreme demand of resources have compelled the linear economy to transform into Circular Economy (CE). In the current scenario, e-waste management has become the top priority of all the developed and developing nations especially those in the transition phase. The generation of e-waste has increased proportionally across the world and created an intense pressure on the firms to implement sustainable practices to redesign and recycle the products. The current status of the developing countries like India confronts number of challenges to manage e-waste produced, and the only possible solution is to minimize the waste generation and practicing recycling processes. For transforming into CEs, there is a need to identify the most influencing key enablers through which an effective and robust e-waste management (e-WM) system can be developed. An extensive literature review and expert judgments are expended to identify the most influencing key enablers of e-WM in circular economies, and, being the highest producer of e-waste, Mumbai (Maharashtra) has been chosen as the case location. To explore the strength of causal and effect enablers, the DEMATEL method is applied. This study has shown that ‘Environmental management system’ (EMS) is the most significant and important driving enabler to influence all the other existing enablers. This study has also highlighted that e-WM can be efficient if it focuses on producing eco-friendly products, developing strict legislations, building green image and supporting the producers to implement CE practices. This study helps stakeholders and policy makers to reduce the burden from the environment and focus on developing an efficient e-WM system on the basis of identified key enablers like EMS and collaboration with environmental partners to contribute towards CE transition.
Показать больше [+] Меньше [-]Influence of nanoscale zero-valent iron on hydraulic conductivity of a residual clayey soil and modeling of the filtration parameter Полный текст
2020
Reginatto, Cleomar | Cecchin, Iziquiel | Salvagni Heineck, Karla | Thomé, Antonio | Reddy, Krishna R.
Contaminated clay soils pose problems to public health and the environment in several parts of the world. Very little is known about the transport of decontaminating agents used in remediation process under natural, undisturbed conditions. Nanomaterials, especially those made of nanoscale zero-valent iron (nZVI), have been most frequently used for remediation of contaminated soils because of their higher reactivity, lower toxicity, and lower cost than other metallic nanoparticles. Even though the nanoparticle size is smaller than soil pores, clogging may occur over time due to agglomeration of nanoparticles, which could reduce the soil’s natural permeability and thereby cause filtration of the nanoparticles. The use of a stabilizer in the nanoparticles can modify the reactivity but improves their mobility in the soil system. Thus, the objective of this work was to evaluate the hydraulic conductivity of residual clay soil under the injection of different types and concentrations of nZVI with and without surfactant stabilizer (NANOFER 25, NANOFER 25S, and NANOFER STAR in powder at 1 g/L, 4 g/L, 7 g/L, and 10 g/L concentrations), and to model transport of these nZVI suspensions in this soil system. Undisturbed cylindrical soil samples collected from the field were used, and hydraulic conductivity tests were performed using a column apparatus. The results showed that the presence of the stabilizer in the nZVI influenced the nanoparticles’ mobility. The nZVI concentrations of 1 and 4 g/L did not affect the natural soil hydraulic conductivity. However, higher concentrations reduced the hydraulic conductivity value, which retarded the migration of nZVI as reflected in the value of filtration parameter.
Показать больше [+] Меньше [-]Theoretical investigations on mechanisms and pathways of CH2ClO2/CHCl2O2 with ClO reactions in the atmosphere Полный текст
2020
Zhang, Yunju | He, Bing | Sun, Yuxi | Huang, Baomei | Wang, Zhiguo | Zhou, Yan
A global and systematic theoretical research on the singlet and triplet potential energy surfaces (PESs) of the CH₂ClO₂/CHCl₂O₂ with ClO reactions are done at the CCSD(T)//B3LYP level and accompanied with RRKM computations to forecast the mechanism and distribution of products. The simulation results revealed that, on the singlet PES, products P1 (CHClO + HO₂ + Cl)/P1 (CCl₂O + HO₂ + Cl) from IM1 (CH₂ClOOOCl)/IM1 (CHCl₂OOOCl) are forecasted to the primary products of the CH₂ClO₂/CHCl₂O₂ + ClO reactions, which are initiated by the oxygen atom of ClO radical addition to the terminal-O atom of CH₂ClO₂/CHCl₂O₂ barrierlessly, while other product channels contribute less to the whole reactions owing to higher barriers. Two other isomers, including IM2 (CH₂ClOOClO) and IM3 (CH₂ClOClO₂) for the CH₂ClO₂ + ClO reaction, and three other isomers, including IM2 (CHCl₂OOClO), IM3 (CHCl₂OClO₂), and IM4 (CHCl₂ClO₃) for the CHCl₂O₂ + ClO reaction, could be produced as less significant products. RRKM calculations presented that the initial adducts IM1 (CH₂ClOOOCl)/IM1 (CHCl₂OOOCl) are the primary products at T < 400 K and T < 600 K, respectively, and products P1 (CHClO + HO₂ + Cl)/P1 (CCl₂O + HO₂ + Cl) are dominant the reactions at T ≥ 400 K and T ≥ 600 K, respectively. The atmospheric lifetime of CH₂ClO₂ and CHCl₂O₂ in ClO is around 4.61 and 3.24 h, respectively.
Показать больше [+] Меньше [-]Modification of photocatalytic property of BaTiO3 perovskite structure by Fe2O3 nanoparticles for CO2 reduction in gas phase Полный текст
2020
Zangeneh, Nazanin Panahi | Sharifnia, Shahram | Karamian, Elham
In this work, perovskite structure of BaTiO₃ was coupled with Fe₂O₃ in different molar ratios achieving the best photocatalytic performance of CO₂ reduction in the presence of CH₄ as reducing agent; both of them are main greenhouse gases. The photocatalysts were synthesized by facile hydrothermal method. The samples were characterized by XRD, FTIR, FESEM, EDX, UV–Vis DRS, and photoluminescence (PL) analyses. The BaTiO₃ synthesized in this research showed a weak PL signal which is due to the intrinsic ferroelectric property as has been observed in previous reports. Compared to the pure BaTiO₃ and Fe₂O₃, the heterojunctions exhibited enhanced photocatalytic activity. The maximum CO₂ reduction under visible light irradiation was obtained to be 22% during 60 min process time. The enhanced photocatalytic activity could be attributed to the increased optical absorption, the good separation, and immigration of photogenerated charge carriers that decreased the recombination rate of charge carriers in the n–n heterojunction.
Показать больше [+] Меньше [-]A nexus between environmental literacy, environmental attitude and healthy living Полный текст
2020
Biswas, Aindrila
It has been widely acknowledged that environmental literacy can provide a strong foundation for future environmental responsiveness, as well as help in the transition towards more sustainable societies and healthy living. According to environmentalists and social scientists, behavioural intentions to sustainable consumption and lifestyle among citizens will help to nurture global environmental and economic sustainability and foster environment and human health development. The study tries to assess the adoption of sustainable lifestyle and healthy lifestyle practices through the designing and demonstration of quantitative method applying environmental literacy as a major predictor in the process which leverages environmental attitude towards such outcomes based on a literacy-sustainability-lifestyle-health modelling framework. The gap between learning and implementation should be addressed through integration of sustainability issues in awareness campaigns by government, NGOs, local bodies and educational institutions.
Показать больше [+] Меньше [-]Estimation of potential ecological carrying capacity in China Полный текст
2020
Xu, Baicui | Pan, Jinghu
It is urgent to explore the potential ecological carrying capacity (PECC) of regions where the study of ecological carrying capacity (ECC) is difficult to meet the real-world requirements of building an ecological civilization. In this study, classification and regression tree models were applied for estimating potential normalized difference vegetation index (PNDVI) based on climate variables and training data of actual NDVI. Then, potential net primary productivity (PNPP) was simulated by using Carnegie-Ames-Stanford Approach (CASA) model and PNDVI. On this basis, PECC of 31 provinces in China was estimated using the improved ecological footprint model and compared results with actual condition in 2015. The results showed the following: per capita PECC presented immense spatial differences, with high values in the northwest and low values in the southeast. The total PECCs of eight provinces were far greater than their actual total ECCs in 2015. Human activities in five provinces had the greatest negative impact on the ecological environment and the greatest pressure on ecological restoration. This study provided a new way to estimate the spatial distribution of potential ecological carrying capacity and found that spatial simulations of PNDVI, PNPP, and PECC can better quantify the difference between actual and potential ecological conditions under external pressures and can provide a trustworthy scientific basis for formulating differentiated ecological restoration strategies.
Показать больше [+] Меньше [-]Electrochemical determination of 4-nitrophenol in environmental water samples using porous graphitic carbon nitride-coated screen-printed electrode Полный текст
2020
Ramalingam, Manikandan | Ponnusamy, Vinoth Kumar | Sangilimuthu, Sriman Narayanan
We demonstrate a facile preparation of novel oxidized graphitic carbon nitride (O-gC₃N₄) applied as an efficient electrocatalyst for highly sensitive electrochemical detection of 4-nitrophenol (4-NP) in environmental water samples. As-prepared O-gC₃N₄ were characterized by attenuated total reflection infrared spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction methods for the confirmation of different functional groups and structural phase of O-gC₃N₄. The surface morphology of the O-gC₃N₄ was characterized using field emission scanning electron microscopy and high-resolution transmission electron microscopy. Results revealed that the synthesized gC₃N₄ possessed acid functional groups, nanosheet with porous in nature. The O-gC₃N₄ was drop cast on the screen-printed electrode (SPE), and it was applied for electrochemical determination of 4-NP using cyclic voltammetry and differential pulse voltammetry (DPV) techniques. The O-gC₃N₄/SPE exhibited excellent electrocatalytic activity towards 4-NP detection. Under the optimized experimental conditions, the DPV response of O-gC₃N₄/SPE showed good linear range from 0.0033 to 0.313 μM with a detection limit (S/N = 3) of 0.075 μM. The developed electrode has successfully applied for the determination of 4-NP in different environmental water samples, and the results have shown satisfied.
Показать больше [+] Меньше [-]Secondhand smoke exposure at home and public places among smokers and non-smokers in India: findings from the Global Adult Tobacco Survey 2016–17 Полный текст
2020
Tripathy, Jaya Prasad
Secondhand smoke (SHS) accounts for 0.9 million deaths and 24 million disability adjusted life years (DALYs) annually. Nearly 30% of adults in India are exposed to SHS in India. To reduce SHS exposure, India enacted a smoke-free law in 2003 under which smoking in public places is banned. However, the compliance to this law has been variable in several assessments in the country. A better understanding of the nature and extent of SHS exposure can help inform better implementation of national smoke-free policies. The Global Adult Tobacco Survey (GATS) India 2016–17 collects information on the self-reported prevalence of SHS exposure in homes, workplaces, government buildings, restaurants, public transportation and health care facilities among adults (> 15 years of age).The present study utilized the GATS India 2016–17 dataset to provide estimates of SHS exposure among adults in India in homes, workplace and other public places, across gender and age groups and among the overall population and non-smokers. Weighted analysis was carried out. In the overall population, exposure to SHS in the home was 29.2%, more among young females. In workplaces, exposure to SHS was 29.2% overall, significantly higher among males (32.5%) compared to females (17.8%). In public buildings such as health care facilities and government offices, SHS exposure was less with 15.6% and 21.2% respectively. SHS exposure was high in restaurants with 39.3% overall, significantly higher among males (43.2%) compared to females (22.2%). Similar results were also seen among non-smokers. A large proportion of adults in India, both smokers and non-smokers are exposed to SHS in their homes, workplaces and other public places, especially restaurants, workplaces and public transportation. Females are more exposed to SHS at home, whereas males are more exposed in public places including workplaces. High SHS exposure among youths is also a concern. Stricter enforcement of legislation is required to ensure 100% smoke-free homes, public places and workplaces and reduce SHS exposure.
Показать больше [+] Меньше [-]Protective effect of aged garlic extracts against hepatotoxicity induced by ethephon in Wistar albino rat Полный текст
2020
Al-Brakati, Ashraf
The current study was designed to demonstrate the hepatoprotective effect of aged garlic extract (AGE) against ethephon-induced liver toxicity in rats. Sixty male Wistar albino rats were divided into four groups as follows: the control group; AGE group was administered with 250 mg/kg; the ethephon group was orally given 200 mg/kg; and AGE + ethephon group was treated with ethephon for 4 weeks and then given AGE for another 4 weeks using the same dosage. The ethephon administration impaired the balance between oxidants and antioxidants as evidenced by the increased level of malondialdehyde (MDA) and the decreased concentration of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). Biochemical findings showed a significant decrease in the red blood corpuscles (RBCs) count, hemoglobin (Hb) content, and hematocrit (HCT) level, with a significant increase in the white blood cells count. In addition, ethephon produced a significant decrease in levels of aspartate transaminase (AST) and alanine transaminase (ALT) with a decrease in albumin level. Furthermore, histological investigation showed dilation of the hepatic central vein and dilation of blood sinusoids which were congested with inflammatory cellular infiltrate. Moreover, examination of the liver using transmission electron microscopy showed a disturbance in the nuclear membranes and degenerating mitochondria with a rise in the cytoplasmic vacuoles by cellular edema. Interestingly, AGE administration was found to attenuate the histological deformations and biochemical alteration produced by ethephon. These findings suggest that AGE supplementation could be used to reverse the hepatic injury following ethephon exposure through its antioxidant capacity.
Показать больше [+] Меньше [-]Evaluation of two contrasted activated carbon-based sequestration strategies to reduce soil-bound chlordecone bioavailability in piglets Полный текст
2020
Delannoy, Matthieu | Techer, Didier | Yehya, Sarah | Razafitianamaharavo, Angelina | Amutova, Farida | Fournier, Agnès | Baroudi, Moumen | Montarges-Pelletier, Emmanuelle | Rychen, Guido | Feidt, Cyril
Evaluation of two contrasted activated carbon-based sequestration strategies to reduce soil-bound chlordecone bioavailability in piglets Полный текст
2020
Delannoy, Matthieu | Techer, Didier | Yehya, Sarah | Razafitianamaharavo, Angelina | Amutova, Farida | Fournier, Agnès | Baroudi, Moumen | Montarges-Pelletier, Emmanuelle | Rychen, Guido | Feidt, Cyril
Chlordecone (Kepone) (CLD) is a highly persistent pesticide formerly used in the French West Indies. High levels of this pesticide are still found in soils and represent a subsequent source of contamination for outdoor-reared animals which may ingest involuntary non negligible amounts of soil. In that context, sequestering matrices like activated carbons (ACs) may be used to efficiently decrease the bioavailability of such organic pollutants. The present study intends to assess the respective efficiency of two sequestering strategies where two different ACs were provided either via feed incorporation or via soil amendment. This study involved 20 piglets randomly distributed into 5 experimental groups (4 replicates). All groups were exposed to 10 μg of CLD per kg of BW per day during 10 days via a contaminated soil. In both “Soil-ACs” treatment groups, the contaminated soil was amended by 2% (mass basis) of one of the two ACs. The two “Feed-ACs” groups received the contaminated soil and one dough ball containing 0.5% (mass basis) of one of the ACs. The piglets were then euthanized before collection of pericaudal adipose tissue and the whole liver and CLD analysis. A significant decrease of CLD concentrations in liver and adipose tissue was observed only in the “Soil-ACs” groups in comparison with the control group (P < 0.001). This decrease was particularly important for the coconut shell activated carbon where relative bioavailability was found lower than 1.8% for both tissues.
Показать больше [+] Меньше [-]Evaluation of two contrasted activated carbon-based sequestration strategies to reduce soil-bound chlordecone bioavailability in piglets Полный текст
2020
Delannoy, Matthieu | Techer, Didier | Yehya, Sarah | Razafitianamaharavo, Angelina | Amutova, Farida | Fournier, Agnès | Baroudi, Moumen | Montargès-Pelletier, Emmanuelle | Rychen, Guido | Feidt, Cyril | Unité de Recherches Animal et Fonctionnalités des Produits Animaux (URAFPA) ; Université de Lorraine (UL)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE) | Lebanese University, Department of Health and Environment, Faculty of Public Health Section III. Tripoli, Lebanon | Laboratoire Interdisciplinaire des Environnements Continentaux (LIEC) ; Institut Ecologie et Environnement - CNRS Ecologie et Environnement (INEE-CNRS) ; Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Terre et Environnement de Lorraine (OTELo) ; Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS) | Al-Farabi Kazakh National University [Almaty] (KazNU) | French National Research Agency (ANR)European Commission16-CE21-0008 | ANR-16-CE21-0008,INSSICCA,Stratégies innovantes pour sécuriser les systèmes d'élevage dans les zones contaminées par la chlordécone. Une approche modèle développée dans les Antilles et applicable dans les zones contaminées à l'échelle mondiale(2016)
International audience | Chlordecone (Kepone) (CLD) is a highly persistent pesticide formerly used in the French West Indies. High levels of this pesticide are still found in soils and represent a subsequent source of contamination for outdoor-reared animals which may ingest involuntary non negligible amounts of soil. In that context, sequestering matrices like activated carbons (ACs) may be used to efficiently decrease the bioavailability of such organic pollutants. The present study intends to assess the respective efficiency of two sequestering strategies where two different ACs were provided either via feed incorporation or via soil amendment. This study involved 20 piglets randomly distributed into 5 experimental groups (4 replicates). All groups were exposed to 10 mu g of CLD per kg of BW per day during 10 days via a contaminated soil. In both "Soil-ACs" treatment groups, the contaminated soil was amended by 2% (mass basis) of one of the two ACs. The two "Feed-ACs" groups received the contaminated soil and one dough ball containing 0.5% (mass basis) of one of the ACs. The piglets were then euthanized before collection of pericaudal adipose tissue and the whole liver and CLD analysis. A significant decrease of CLD concentrations in liver and adipose tissue was observed only in the "Soil-ACs" groups in comparison with the control group (P < 0.001). This decrease was particularly important for the coconut shell activated carbon where relative bioavailability was found lower than 1.8% for both tissues.
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