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Performance evaluation of a decentralized wastewater treatment system in India Полный текст
2019
Singh, Anju | Sawant, Megha | Kamble, Sheetal Jaisingh | Herlekar, Mihir | Starkl, Markus | Aymerich, Enrique | Kazmi, Absar
A Decentralized Wastewater Treatment System (DEWATS) provides an economically feasible and efficient wastewater treatment solution especially in developing countries. It has an enormous potential for developing a sustainable environmental sanitation system. In this study, the treatment efficiency of eight DEWATS plants was evaluated in the state of Maharashtra, India, for their performance in terms of selected physico-chemical parameters of the wastewater. Although the efficiency of some of the plants was lower than that reported in literature, the effluent quality of all the plants was within the permissible discharge limits of the Central Pollution Control Board for all the parameters. Comprehensive assessment of Plant I was carried in terms of its technical and socio-economic aspects. Moreover, LCA tool has been utilized to evaluate the environmental impacts of the operation stage of DEWATS. The midpoint, CML 2001 (April 2015) methodology was adopted, in which 11 impact categories were considered. From the life cycle impact assessment and interpretation, the main impacts are identified as releases of COD, P-PO₄³⁻, and N-NH₄⁺ to water bodies and disposal of sludge. Due to negligible energy consumption, the operation stage was found to be less damaging to the environment. It was concluded that DEWATS can be a good alternative for treating wastewater with negligible energy and chemical consumption.
Показать больше [+] Меньше [-]Attitudes to climate change, perceptions of disaster risk, and mitigation and adaptation behavior in Yunlin County, Taiwan Полный текст
2019
Lee, Yung-Jaan | Tung, Chuan-Ming | Lin, Shih-Chien
Issues that are associated with climate change have global importance. Most related studies take a national or regional perspective on the impact of climate change. Taiwan is constrained by its geographical conditions, which increase its vulnerability to climate change, especially in its western coastal areas. The county that is most affected by climate change is Yunlin. In 2013–2014, projects that were sponsored by Taiwan’s government analyzed the relationship among synthesized vulnerability, ecological footprint (EF) and adaptation to climate change and proposed 15 categories of synthesized vulnerability and EF values. This study further examines the relationship between vulnerability and EF values and examines how residents of four townships—Linnei, Sihu, Mailiao, and Huwei—cope with the effects of climate change. This study investigates whether the residents of the four townships vary in their attitudes to climate change, their perceptions of disaster risk, and their behavioral intentions with respect to coping with climate change. The structural equation model (SEM) is used to examine the relationships among attitudes to climate change, perceptions of disaster risk, and the behavioral intentions of residents in townships with various vulnerabilities to climate change. The results that are obtained using the SEM reveal that climate change mitigation/adaptation behavior is affected by attitudes to climate change and perceptions of disaster risk. However, the effects of attitudes and perceptions on mitigation and adaptation that are mediated by place attachment are not statistically significant.
Показать больше [+] Меньше [-]Toxicological aspects of trihalomethanes: a systematic review Полный текст
2019
de Castro Medeiros, Luciana | de Alencar, Feliphe Lacerda Souza | Navoni, Julio Alejandro | de Araujo, André Luis Calado | do Amaral, Viviane Souza
Chlorine is considered the most used chemical agent for water disinfection worldwide. However, water chlorination can lead to by-product generation which can be toxic to humans. The present study aimed to perform a systematic review on the toxicity of trihalomethanes (THMs) through bioindicators of cytotoxicity, genotoxicity, and mutagenicity. The results showed that studies on the effects of THMs on DNA are a current research concern for evaluating the toxicity of the pure compounds and real samples involving several types including water for recreational use, reused water, and drinking water. THMs deleterious effects have been assessed using several biosystems, where the Ames test along with experimental animal models were the most cited. A wide range of THM concentrations have been tested. Nevertheless, DNA damage was demonstrated, highlighting the potential human health risk. Among the studied THMs, chloroform presented a different action mechanism when compared with brominated THMs, with the former being cytotoxic while brominated THMs (bromodichloromethane, bromoform, and dibromochloromethane) were cytotoxic, genotoxic, and mutagenic. The described evidence in this research highlights the relevance of this topic as a human health issue. Nevertheless, research aimed to represent THMs current exposure conditions in a more accurate way would be needed to understand the real impact on human health.
Показать больше [+] Меньше [-]Nanoanalytics: history, concepts, and specificities Полный текст
2019
Faucher, Stéphane | Le Coustumer, Philippe | Lespes, Gaëtane
This article deals with analytical chemistry devoted to nano-objects. A short review presents nano-objects, their singularity in relation to their dimensions, genesis, and possible transformations. The term nano-object is then explained. Nano-object characterization activities are considered and a definition of nanoanalytics is proposed. Parameters and properties for describing nano-objects on an individual scale and on the scale of a population are also presented. They enable the specificities of analytical activities to be highlighted in terms of multi-criteria description strategies and observation scale. Special attention is given to analytical methods, their dimensioning and validation.
Показать больше [+] Меньше [-]Microwave-accelerated sorption of cationic dyes onto green marine algal biomass Полный текст
2019
Elgarahy, Ahmed M. | Elwakeel, Khalid Z. | Elshoubaky, Gihan A. | Mohammad, Samya H.
Monolithic algal green powder (MAGP) was fabricated based on the marine green macroalga Enteromorpha flexuosa. It was scrutinized by using scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), Fourier transform infrared (FT-IR), point of zero charge (PHPZC), and Brunauer–Emmett–Teller (BET) surface area. The ability of Enteromorpha flexuosa to capture both crystal violet (CV) and methylene blue (MB) from aqueous solutions was evaluated. The influence of variable conditional parameters on CV dye and MB dye batch sorption was investigated. Results showed that percentage removal of 90.3% and 93.4% were obtained under optimum conditions of variables for CV and MB, respectively. Effect of microwave radiation on dye sorption was also appraised. Processing the sorption under microwave irradiation (microwave-enforced sorption, MES) increases mass transfer and a contact time as low as 1 min is sufficient under optimized conditions (exposure time and power) reaching the equilibrium. The reusability of MAGP sorbent was achieved for four cycles of sorption/desorption by using 0.5 M HCl. The ability of MAGP for cationic dyes removal from spiked tap water and petrochemical plant discharge wastewater samples was successfully registered. Ultimately, the displayed data showed a superior and excellent ability of algal powder to be exploited as a green, harmless, and effective sorbent for cationic dye removal.
Показать больше [+] Меньше [-]The dirty energy dilemma via financial development and economic globalization in Pakistan: new evidence from asymmetric dynamic effects Полный текст
2019
T̤āriq, Muḥammad | Xu, Yingzhi | Muhammad, Faqeer | Alam, Khalid Mehmood
Energy strategy has been an essential strand in the view of economists in achieving rapid development process of any country. The recent wave of globalization exerts pressure on energy consumption via financial development which ultimately vindicates economic growth. This paper has covered a period of 1976–2016 using annual data for the empirical analysis and constructed a growth equation as the main equation and the energy consumption equation as a channel equation. The empirical study has been undertaken by performing ARDL and nonlinear autoregressive distributed lag models (NARDL). The bound test result declares a long-run association in both equations. Consequently, energy consumption and economic globalization have significantly enhanced economic growth in the long run. Whereas, financial development index has no influence on the economic growth of Pakistan. The results of channel equation suggested that due to growing the price of crude oil, the energy consumption is reduced in the long run. The increasing imports of energy products and increasing urbanization are conducive for energy consumption in Pakistan. By NARDL model, our empirical findings provide robust support for the existence of asymmetric co-integration linking among underlying variables of the study.
Показать больше [+] Меньше [-]Respiratory health assessment and exposure to polycyclic aromatic hydrocarbons in Mexican indigenous population Полный текст
2019
Rodríguez-Aguilar, Maribel | Díaz de León Martínez, Lorena | García-Luna, Sofía | Gómez Gómez, Alejandro | González Palomo, Ana Karen | Pérez-Vázquez, Francisco Javier | Díaz-Barriga, Fernando | Trujillo, Joyce | Flores Ramírez, Rogelio
Indoor air pollution is an important risk factor for the generation of lung diseases in developing countries. The indigenous population is particularly susceptible to be exposed to the mixture of pollutants from the biomass burning, among them, polycyclic aromatic hydrocarbons (PAHs). The objective of this study was to assess respiratory health and exposure to PAHs in indigenous populations of the Huasteca Potosina in Mexico. The urinary metabolite 1-hydroxypyrene (1-OHP) was evaluated by HPLC with fluorescence detector, the forced expiratory volume in one second (FEV₁) and the FEV₁/FVC ratio (forced vital capacity) by spirometry in the Teenek indigenous adult population of the communities from Tocoy (TOC), Xolol (XOL), and Tanjajnec (TAN). A total of 134 subjects participated in the study: 64 from TOC, 30 from XOL, and 40 from TAN; in all the communities, high percentages of overweight and obesity were presented (from 50 to 73%). The average hours of firewood usage per year were 281.06, 284.6, and 206.6 in TOC, XOL, and TAN, respectively. The average of the three communities of the % FEV₁ post-bronchodilator was 86.1%. There were identified from 4.5 to 6.6% and from 12.5 to 15.5% of spirometric obstructive and restrictive patterns respectively, in all communities. The highest exposure levels reported as median were found in TOC (1.15 μmol/mol of creatinine) followed by TAN (0.94 μmol/mol of creatinine) and XOL (0.65 μmol/mol of creatinine). Considering the magnitude of the indigenous population exposed to pollutants from the biomass burning and the possible effects on respiratory health, it is important to design strategies that mitigate exposure and evaluate the effectiveness through biological monitoring and effects.
Показать больше [+] Меньше [-]Exploring regional differences in the impact of high energy-intensive industries on CO2 emissions: Evidence from a panel analysis in China Полный текст
2019
Liu, Hanchu | Fan, Jie | Zhou, Gan | Wang, Qiang
China is currently the largest CO₂ emitter in the world. Within China, more than 60% of CO₂ emissions originate from high energy-intensive (HEI) industries. Therefore, controlling and reducing CO₂ emissions from HEI industries is crucial if China is to achieve its 2030 emission reduction targets. This study aims to investigate regional differences in the impact of HEI industries on CO₂ emissions in China. This paper presents an analysis of the impact of HEI industries on CO₂ emissions at the national and regional levels using a modified STIRPAT model and provincial panel data from 2000 to 2015 in China. The results show that HEI industries are significant contributors to China’s CO₂ emissions owing to the growth in industries, coal-based energy structure, low level of technology, and outstanding conduction effects. The impact intensity of HEI industries on CO₂ emissions decreases from the western to the central and eastern regions in China because of a huge regional difference in industrial structure, energy structure, R&D investment, and industrial transfer. Our findings have important implications for policymakers in China by indicating that regional policies concerning HEI industries should be differentiated to successfully reduce CO₂ emissions and meet national targets.
Показать больше [+] Меньше [-]Potential control of toxic cyanobacteria blooms with Moroccan seaweed extracts Полный текст
2019
El Amrani Zerrifi, Soukaina | Tazart, Zakaria | El Khalloufi, Fatima | Oudra, Brahim | Campos, Alexandre | Vasconcelos, Vitor
Potential control of toxic cyanobacteria blooms with Moroccan seaweed extracts Полный текст
2019
El Amrani Zerrifi, Soukaina | Tazart, Zakaria | El Khalloufi, Fatima | Oudra, Brahim | Campos, Alexandre | Vasconcelos, Vitor
Marine macroalgae are a promising source of diverse bioactive compounds with applications in the biocontrol of harmful cyanobacteria blooms (cyanoHABs). In this work, we evaluated the potential algicidal activities of 14 species of seaweed collected from the coast of Souiria Laqdima, Morocco. Methanol extracts were screened in solid and liquid medium against the growth of the toxic cyanobacteria Microcystis aeruginosa and the microalgae Chlorella sp. used as food supplement. The results in solid medium revealed that the algicidal activity was limited to M. aeruginosa with the extract of Bornetia secundiflora showing the highest growth inhibition activity against Microcystis (27.33 ± 0.33 mm), whereas the extracts of Laminaria digitata, Halopytis incurvus, Ulva lactuca, and Sargasum muticum showed no inhibition. In liquid medium, the results indicated that all methanolic extracts of different macroalgae tested have a significant inhibitory effect on M. aeruginosa compared with that of the negative control. The maximum inhibition rates of M. aeruginosa were produced by the extracts of Bifurcaria tuberculata, Codium elongatum, and B. secundiflora. Moreover, the extracts of B. secundiflora recorded the maximum inhibition rate of Chlorella sp. Overall, the results highlight the potential of the extracts from macroalgae to control toxic cyanobacteria species.
Показать больше [+] Меньше [-]Potential control of toxic cyanobacteria blooms with Moroccan seaweed extracts Полный текст
2019 | 2020
Zerrifi, S. | Tazart, Z. | El Khalloufi, F. | Oudra, B. | Campos, A. | Vasconcelos, V. | Centro Interdisciplinar de Investigação Marinha e Ambiental
Marine macroalgae are a promising source of diverse bioactive compounds with applications in the biocontrol of harmful cyanobacteria blooms (cyanoHABs). In this work, we evaluated the potential algicidal activities of 14 species of seaweed collected from the coast of Souiria Laqdima, Morocco. Methanol extracts were screened in solid and liquid medium against the growth of the toxic cyanobacteria Microcystis aeruginosa and the microalgae Chlorella sp. used as food supplement. The results in solid medium revealed that the algicidal activity was limited to M. aeruginosa with the extract of Bornetia secundiflora showing the highest growth inhibition activity against Microcystis (27.33 ± 0.33 mm), whereas the extracts of Laminaria digitata, Halopytis incurvus, Ulva lactuca, and Sargasum muticum showed no inhibition. In liquid medium, the results indicated that all methanolic extracts of different macroalgae tested have a significant inhibitory effect on M. aeruginosa compared with that of the negative control. The maximum inhibition rates of M. aeruginosa were produced by the extracts of Bifurcaria tuberculata, Codium elongatum, and B. secundiflora. Moreover, the extracts of B. secundiflora recorded the maximum inhibition rate of Chlorella sp. Overall, the results highlight the potential of the extracts from macroalgae to control toxic cyanobacteria species. | We acknowledge the projects TOXICROP (823860) funded by the H2020 program MSCA-RISE-2018 and the project VALORMAR (24517) of the 10/SI/2016-I&DT Empresarial- Programas Mobilizadores funded by the European Regional Development Fund (ERDF) and by the European Social Fund (ESF).
Показать больше [+] Меньше [-]Decomplexation of Cr(III)-EDTA and simultaneous abatement of total Cr by photo-oxidation: efficiency and in situ reduction of intermediate Cr(VI) Полный текст
2019
Huang, Xianfeng | Wang, Xiran | Guan, Dong-Xing | Zhou, Huabin | Bei, Ke | Zheng, Xiangyong | Jin, Zhan | Zhang, Yejian | Wang, Qi | Zhao, Min
Most prevailing processes are incapable of removing Cr(III)-organic complexes efficiently and facing the problem of in-process formation of highly toxic Cr(VI) based on oxidation. The efficient decomplexation of Cr(III) complexes and simultaneous abatement of Cr with low Cr(VI) accumulation would be desirable in treatment of Cr(III)-complexed wastewater. Here, we found efficient degradation of Cr(III)-EDTA and simultaneous removal of Cr by forming Cr₂O₃ precipitate from simulated solution as well as an electroplating effluent under UV irradiation. The results showed a complete degradation of Cr(III)-EDTA after reaction time of 60 min and 70–80% of TOC mineralization within 180 min as well. About 90% of Cr(III) precipitated as Cr₂O₃ simultaneously, with the residual total Cr below 1.5 mg/L. The degradation of Cr(III)-EDTA was a stepwise de-acetate group process, as proven by the obvious attenuation of peaks related to carboxyl groups and C–C bond from FT-IR spectra of Cr(III)-EDTA and significant mineralization of TOC after UV irradiation. Based on negligible accumulation of Cr(VI) (less than 0.1 mg/L) under N₂-sparged condition, the C-centered radicals from the β-fragmentation of O-centered radicals formed by photo-induced ligand-to-metal charge transfer were responsible for the in situ reduction of intermediate Cr(VI), resulting in the low accumulation of Cr(VI). The addition of 20 mg/L Fe²⁺ was capable of removing the remaining Cr(VI) and total Cr, with Cr(VI) and total Cr less than 0.1 and 1.0 mg/L, respectively. Moreover, the photo-oxidation process combined with Fe²⁺ addition were efficient in removing other Cr(III) complexes, such as Cr(III)-citrate and those from a realistic electroplating effluent. We believe that this study would provide an alternative option for efficient degradation of Cr(III) complexes and simultaneous abatement of Cr from contaminated water.
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