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Socio-economic and environmental analysis on solar thermal energy-based polygeneration system for rural livelihoods applications on an Island through interventions in the energy-water-food nexus النص الكامل
2022
Thomas, Sanju | Sahoo, Sudhansu S. | Ajithkumar, G | Thomas, Sheffy | Rout, Auroshis | Mahapatra, Swarup K.
Rural electrification is constrained by grid extension infrastructural cost, isolated low rural populations, lack of anchor loads, and repayment potential of villagers while decentralized renewable energy power is constrained by high capital cost, low reliability, and non-workable business models. Solar thermal energy can produce electricity, heating, cooling, water, and fuel and has the potential for storage for livelihood applications. Hence solar thermal energy-based cogeneration and polygeneration systems have the potential for intervention in rural livelihoods with a focus on the energy-land–water-food nexus. However, standalone solar thermal systems are capital intensive and shadowed by photovoltaics. In the current work, an island in the Indian Ocean is considered for the study, and a solar thermal energy-based hybrid polygeneration system is designed with end products such as electricity, heating, cooling for food storage, and desalinating to get pure water. The turbine, VAM, pasteurization unit, and membrane distillation unit are the considered components in the present analysis. The thermodynamic properties of the key components of the polygeneration system are identified and the energy and entropy balance of the system is done. The levelised cost of production of polygeneration outputs for 25-year operational life with an accelerated depreciation of 30% of the capital cost, over 8 years is carried out. It is found that the electricity and water pricing are INR 14.71 and INR 14.01 per unit which are not attractive. Normalization is done by adjusting the price of other polygeneration outputs namely refrigeration, hot water, and pasteurizing to make the electricity and water pricing feasible to achieve an IRR of 12.99% and payback of 9 years at a 5% annual escalation. The social cost saved with the benefit of polygeneration outputs is cumulated considering value addition in the supply chain to save agricultural produce and milk, which otherwise would have spoiled. The annual carbon emissions that are curtailed with solar thermal polygeneration outputs are cumulated and found to be 434 tonnes of carbon. The social cost and environmental cost due to carbon are considered as an incentive in the cost economic economics of polygeneration system and it is found that the IRR and payback can be improved to 17.98% and 6.2 years respectively. The work recommends policy interventions to promote decentralized solar thermal polygeneration systems for impact on rural livelihoods with a focus on the energy-water-food nexus.
اظهر المزيد [+] اقل [-]Fast responsive colorimetric and ratiometric fluorescence chemoprobe based on a 1,8–naphthalimide for nM recognition of Cu2+ and its application in real food and drinkable water samples النص الكامل
2022
Arslan, Fatma Nur | Aydin, Duygu | Elmas, Sukriye Nihan Karuk
In this research, a novel 1,8–naphthalimide–based colorimetric and ratiometric fluorescence chemoprobe (NAPH) was realistically developed for the recognition of copper (II) (Cu²⁺) in different vegetables and drinkable water samples. The sensing studies of NAPH depicted a ratiometric ''turn–on'' fluorescent response from bright yellow to blue as well as a colorimetric response toward Cu²⁺ from yellow to colorless, and it was found to be unselective towards various metal ions, anions and amino acids. The fast response of NAPH to Cu²⁺ caused a wavelength shift from 550 nm to 454 nm, and hence NAPH was used to recognize Cu²⁺ with an ultralow detection limit (9.53 nM). To validate the spectral data of NAPH, the study was performed using important analytical parameters and statistical tests. The binding stoichiometry between NAPH and Cu²⁺ was computed as 1:1 by Job's plot method as well MALDI TOF MS. Besides, the binding constant between the NAPH and Cu²⁺ was found to be 6.84 × 10³ M–¹. In addition to sensing studies, density–functional theory (DFT) findings strongly confirmed spectral data, and the Smartphone sensing results demonstrated that NAPH could be utilized as a powerful tool for the monitoring of Cu²⁺ without the need for sophisticated equipment. A test paper application was also performed to achieve semi–quantitative detection and to produce test kits with excellent selectivity toward Cu²⁺ without interfering metal ions. Furthermore, the newly designed probe NAPH was not only successfully used to recognize Cu²⁺ in bottled drinking waters (93.93–103.97%) but also was employed for vegetables with satisfactory results (92.97–109.92%).
اظهر المزيد [+] اقل [-]Simultaneously speciation and determination of manganese (II) and (VII) ions in water, food, and vegetable samples based on immobilization of N-acetylcysteine on multi-walled carbon nanotubes النص الكامل
2022
Rakhtshah, Jamshid | Shirkhanloo, Hamid | Dehghani Mobarake, Mostafa
A novel method based on the immobilization of N-acetylcysteine on chloro-functionalized multi-walled carbon nanotubes (MWCNTs@NAC) was used for the speciation of manganese ions [Mn (II) and Mn(VII)] in water samples. Also, the total manganese (TMn) in vegetables and food samples was determined by the AT-FAAS. By ultrasound-assisted-dispersive ionic liquid trap micro solid-phase extraction (UA-DILT-μ-SPE), the Mn (II)/Mn(VII) ions were extracted in the presence of MWCNTs@NAC for 50 mL of water samples at a pH of 6.5 and 3.0, respectively. The adsorption capacity of MWCNTs@NAC for Mn(II) and Mn(VII) ions was obtained at 146.7 mg g⁻¹ and 138.8 mg g⁻¹, respectively. Under the optimized conditions, the detection limits (LOD), linear range (LR), and enrichment factor (EF) for Mn(II) and Mn(VII) ions were obtained (0.12 μg L⁻¹; 0.14 μg L⁻¹), (0.48–36 μg L⁻¹; 0.55–38.1 μg L⁻¹) and (100.2; 94.5), respectively. The proposed methodology was successfully validated by the CRM samples.
اظهر المزيد [+] اقل [-]A Collaborative Framework for Hydropower Development and Sustainable Livelihood of Farmers in the Lancang-Mekong River Basin: A Review with the Perspective of Energy-Water-Food Nexus النص الكامل
2022
Shuai Zhong | Yidong Zhu | Jianan Zhao | Lei Shen
With the process of poverty eradication and economic growth, hydropower development becomes increasingly important because of its huge potential advantages in the Lancang-Mekong River Basin. However, the complex topography and rich resource endowments in the Lancang-Mekong River Basin bring a variety of potential risks and uncertainties in hydropower development, which has an important impact on the sustainable livelihood of farmers. There is an urgent need for countries in the Lancang-Mekong River Basin to systematically assess hydropower projects, especially their impact on the sustainable livelihoods of farmers. Based on the systematic analysis of relevant literature, this study established a collaborative framework of hydropower development and farmers’ sustainable livelihood, including theoretical framework, indicator system and model structure. The purpose is to explore the interaction mechanism of energy and water resources utilization, food security and sustainable livelihood of farmers in hydropower development. The findings can provide scientific and technological support for the Belt and Road Initiative, poverty reduction and sustainable development in the river basin.
اظهر المزيد [+] اقل [-]Gender equity and social inclusion in the water-energy-food-ecosystems (WEFE) nexus: Frameworks and tools for moving from resource-centric to people-centric WEFE nexus approaches
2022
Jalonen, Riina | Zaremba, Haley | Petesch, Patti | Elias, Marlène | Estrada-Carmona, Natalia | Tsvuura, Susan | Koirala, Sanju
This learning module focuses on how to integrate gender equality and social inclusion (GESI) considerations in WEFE approaches to contribute to more effective and equitable WEFE initiatives for current and future generations. Intentionally focusing on GESI in the design, implementation, and monitoring of WEFE initiatives is critical to ensure that these initiatives do not harm – and, rather, benefit – women and vulnerable groups and communities. At the end of this lesson, learners will be able to: (1) Explain the importance of GESI for achieving sustainable development outcomes in the WEFE nexus, (2) Describe common GESI challenges and issues that WEFE projects face, (3) Describe the main steps for better addressing GESI considerations
اظهر المزيد [+] اقل [-]Revisiting the Biological Behavior of Salmonella enterica in Hydric Resources: A Meta-Analysis Study Addressing the Critical Role of Environmental Water on Food Safety and Public Health النص الكامل
2022
Alan Douglas de Lima Rocha | Rafaela Gomes Ferrari | Walter Esfrain Pereira | Laiorayne Araújo de Lima | Patrícia Emília Naves Givisiez | Andrea Isabel Moreno-Switt | Magaly Toro | Enrique Jesús Delgado-Suárez | Jianghong Meng | Celso José Bruno de Oliveira
The increasing number of studies reporting the presence of Salmonella in environmental water sources suggests that it is beyond incidental findings originated from sparse fecal contamination events. However, there is no consensus on the occurrence of Salmonella as its relative serovar representation across non-recycled water sources. We conducted a meta-analysis of proportions by fitting a random-effects model using the restricted maximum-likelihood estimator to obtain the weighted average proportion and between-study variance associated with the occurrence of Salmonella in water sources. Moreover, meta-regression and non-parametric supervised machine learning method were performed to predict the effect of moderators on the frequency of Salmonella in non-recycled water sources. Three sequential steps (identification of information sources, screening and eligibility) were performed to obtain a preliminary selection from identified abstracts and article titles. Questions related to the frequency of Salmonella in aquatic environments, as well as putative differences in the relative frequencies of the reported Salmonella serovars and the role of potential variable moderators (sample source, country, and sample volume) were formulated according to the population, intervention, comparison, and outcome method (PICO). The results were reported according to the Preferred Reporting Items for Systematic Review and Meta-Analyzes statement (PRISMA). A total of 26 eligible papers reporting 148 different Salmonella serovars were retrieved. According to our model, the Salmonella frequency in non-recycled water sources was 0.19 [CI: 0.14; 0.25]. The source of water was identified as the most import variable affecting the frequency of Salmonella, estimated as 0.31 and 0.17% for surface and groundwater, respectively. There was a higher frequency of Salmonella in countries with lower human development index (HDI). Small volume samples of surface water resulted in lower detectable Salmonella frequencies both in high and low HDI regions. Relative frequencies of the 148 serovars were significantly affected only by HDI and volume. Considering that serovars representation can also be affected by water sample volume, efforts toward the standardization of water samplings for monitoring purposes should be considered. Further approaches such as metagenomics could provide more comprehensive insights about the microbial ecology of fresh water and its importance for the quality and safety of agricultural products.
اظهر المزيد [+] اقل [-]A Collaborative Framework for Hydropower Development and Sustainable Livelihood of Farmers in the Lancang-Mekong River Basin: A Review with the Perspective of Energy-Water-Food Nexus النص الكامل
2022
Zhong, Shuai | Zhu, Yidong | Zhao, Jianan | Shen, Lei
With the process of poverty eradication and economic growth, hydropower development becomes increasingly important because of its huge potential advantages in the Lancang-Mekong River Basin. However, the complex topography and rich resource endowments in the Lancang-Mekong River Basin bring a variety of potential risks and uncertainties in hydropower development, which has an important impact on the sustainable livelihood of farmers. There is an urgent need for countries in the Lancang-Mekong River Basin to systematically assess hydropower projects, especially their impact on the sustainable livelihoods of farmers. Based on the systematic analysis of relevant literature, this study established a collaborative framework of hydropower development and farmers’ sustainable livelihood, including theoretical framework, indicator system and model structure. The purpose is to explore the interaction mechanism of energy and water resources utilization, food security and sustainable livelihood of farmers in hydropower development. The findings can provide scientific and technological support for the Belt and Road Initiative, poverty reduction and sustainable development in the river basin.
اظهر المزيد [+] اقل [-]Revisiting the biological behavior of salmonella enterica in hydric resources: a meta-analysis study addressing the critical role of environmental water on food safety and public health النص الكامل
2022
Lima Rocha, Alan Douglas de | Gomes Ferrari, Rafaela | Pereira, Walter Esfrain | Lima, Laiorayne Araújo de | Givisiez, Patrícia Emília Naves | Moreno Switt, Andrea Isabel | Toro Ibaceta, Magaly Alejandra | Delgado Suárez, Enrique Jesús | Meng, Jianghong | Oliveira, Celso José Bruno de
The increasing number of studies reporting the presence of Salmonella in environmental water sources suggests that it is beyond incidental findings originated from sparse fecal contamination events. However, there is no consensus on the occurrence of Salmonella as its relative serovar representation across non-recycled water sources. We conducted a meta-analysis of proportions by fitting a random-effects model using the restricted maximum-likelihood estimator to obtain the weighted average proportion and between-study variance associated with the occurrence of Salmonella in water sources. Moreover, meta-regression and non-parametric supervised machine learning method were performed to predict the effect of moderators on the frequency of Salmonella in non-recycled water sources. Three sequential steps (identification of information sources, screening and eligibility) were performed to obtain a preliminary selection from identified abstracts and article titles. Questions related to the frequency of Salmonella in aquatic environments, as well as putative differences in the relative frequencies of the reported Salmonella serovars and the role of potential variable moderators (sample source, country, and sample volume) were formulated according to the population, intervention, comparison, and outcome method (PICO). The results were reported according to the Preferred Reporting Items for Systematic Review and Meta-Analyzes statement (PRISMA). A total of 26 eligible papers reporting 148 different Salmonella serovars were retrieved. According to our model, the Salmonella frequency in non-recycled water sources was 0.19 [CI: 0.14; 0.25]. The source of water was identified as the most import variable affecting the frequency of Salmonella, estimated as 0.31 and 0.17% for surface and groundwater, respectively. There was a higher frequency of Salmonella in countries with lower human development index (HDI). Small volume samples of surface water resulted in lower detectable Salmonella frequencies both in high and low HDI regions. Relative frequencies of the 148 serovars were significantly affected only by HDI and volume. Considering that serovars representation can also be affected by water sample volume, efforts toward the standardization of water samplings for monitoring purposes should be considered. Further approaches such as metagenomics could provide more comprehensive insights about the microbial ecology of fresh water and its importance for the quality and safety of agricultural products. | Versión publicada - versión final del editor
اظهر المزيد [+] اقل [-]A Non-Stressful Temperature Rise and Greater Food Availability Could Increase Tolerance to Calcium Limitation of Daphnia cf. pulex (Sensu Hebert, 1995) Populations in Cold Soft-Water Lakes النص الكامل
2022
Ramos Rodríguez, Eloisa | Pérez Martínez, María del Carmen | Conde Porcuna, José María
Calcium (Ca) is an important driver of community structure in freshwaters. We examined the combined effects of increased temperatures and variations in food quantity on the tolerance to low Ca of Daphnia pulex. The aim was to predict the impact of climate warming on this keystone zooplanktonic species in cold-climate lakes. We conducted a factorial life-history experiment in a clone of North American Daphnia cf. pulex to analyse the interaction effects of a temperature increase (17.5 degrees C-21 degrees C) within their physiological preferred range and expected by climate warming over the next few decades and a narrow Ca gradient (0.25-1.74 mg Ca L-1) under stressful vs. abundant food conditions. We found a striking positive synergistic effect of Ca and temperature on D. pulex reproduction at high food conditions. Although the increase in temperature to 21 degrees C greatly reduced survival, high energy allocation to reproduction at high food levels allowed the population to succeed in poor Ca (<0.25 mg Ca L-1). Results suggest that climate warming and higher food availability will make the populations of many cold and Ca-limited lakes more tolerant to low Ca levels with higher growth population rates, thereby altering zooplanktonic community structures and inducing potential cascading effects on the food web. | Organismo Autonomo de Parques Nacionales (Ministerio para la Transicion Ecologica y el Reto Demografico, Spain) PN2017-2403S | Junta de Andalucia RNM-125
اظهر المزيد [+] اقل [-]Determination of organophosphorus compounds in water and food samples using a non-enzymatic electrochemical sensor based on silver nanoparticles and carbon nanotubes nanocomposite coupled with batch injection analysis النص الكامل
2022
Porto, Laís Sales | Ferreira, Lucas Franco | Pio dos Santos, Wallans Torres | Pereira, Arnaldo César
This work presents, for the first time, a fast and highly sensitive electrochemical method for determination of three organophosphorus compounds (OPs), diazinon (DZN), malathion (MLT), and chlorpyrifos (CLPF), using a modified pyrolytic graphite electrode (PGE) coupled to batch injection analysis system with multiple pulse amperometric detection (BIA–MPA). The PGE was modified by a nanocomposite based on functionalized carbon nanotubes (CNTf) and silver nanoparticles (AgNPs). The OPs samples were directly analyzed on the modified working electrode surface by BIA-MPA system in Britton-Robinson (BR) buffer 0.15 mol L⁻¹ at pH 6.0. The MPA detection of DZN, MLT and CLPF was performed using two potential pulses, which were sequentially applied on modified PGE at −1.3 V (100 ms) and +0.8 V (100 ms) for selective determination of these three OPs and working electrode cleaning, respectively. Under optimized conditions, the sensor presented a linear range of 0.1–20 μmol L⁻¹ for DZN, 1.0–30 μmol L⁻¹ for MLT and from 0.25 to 50 μmol L⁻¹ for CLPF. The limits of detection (LOD) and quantification (LOQ) of 0.35 and 1.18 μmol L⁻¹ for DZN, 0.89 and 2.98 μmol L⁻¹ for MLT, and 0.53 and 1.78 μmol L⁻¹ for CLPF were obtained. The proposed method exhibited high sensitivity of 0.068, 0.030 and 0.043 mA L μmol⁻¹ for DZN, MLT and CLPF detection, respectively. Furthermore, the BIA-MPA system provided an analytical frequency of 71 determinations per hour for direct determination of these OPs in water and food samples. The modified PGE coupled to BIA-MPA system showed a high stability of electrochemical response for OPs detection with relative standard deviation (RSD) of 1.60% (n = 20). The addition-recovery studies of the proposed method were carried out in tap water, orange juice, and apple fruit real samples, which showed suitable recovery values between 77 and 124%. The analytical performance of the developed sensor provides an attractive alternative method for OPs determination with great potential for a fast and sensitive application in contaminated samples with these pesticides.
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