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Addition of air-nanobubble water to mitigate the inhibition of high salinity on co-production of hydrogen and methane from two-stage anaerobic digestion of food waste Полный текст
2021
Hou, Tingting | Zhao, Jiamin | Lei, Zhongfang | Shimizu, Kazuya | Zhang, Zhenya
Most previous studies have focused on the effects of salt on anaerobic digestion (AD) for hydrogen or methane production. However, the effects of salt on two-stage AD and the related approaches to mitigate the adverse effects of high salinity on hydrogen and/or methane production were seldom addressed. In this study, addition of Air-nanobubble water (Air-NBW) was adopted to mitigate the inhibition of high salinity on co-production of hydrogen and methane from two-stage AD of food waste (FW). In the Air-NBW added reactors with 0–30 g NaCl/L, hydrogen yield was increased by 21–65% with the subsequent methane yield elevated by 14–43% when compared to the corresponding deionized water (DW) group. This study for the first time confirmed that when two-stage AD of FW was exposed to the same salinity level, addition of Air-NBW could enhance enzymatic activities at the individual stage. Results of electron transport system (ETS) activity further demonstrate that addition of Air-NBW may promote the electron transfer associated with the synthesis of hydrogen and methane. Therefore, an efficient approach for hydrogen and methane recovery from the two-stage AD of FW under high salinity was proposed through improving microbial electron transfer and corresponding enzymatic activities at each stage via Air-NBW addition.
Показать больше [+] Меньше [-]Phthalates and organophosphate esters in surface water, sediments and zooplankton of the NW Mediterranean Sea: Exploring links with microplastic abundance and accumulation in the marine food web Полный текст
2021
Schmidt, Natascha | Castro-Jiménez, Javier | Oursel, Benjamin | Sempéré, Richard
In this study, surface seawater, sediment and zooplankton samples were collected from three different sampling stations in Marseille Bay (NW Mediterranean Sea) and were analyzed for both microplastics and organic plastic additives including seven phthalates (PAEs) and nine organophosphate esters (OPEs). PAE concentrations ranged from 100 to 527 ng L⁻¹ (mean 191 ± 123 ng L⁻¹) in seawater, 12–610 ng g⁻¹ dw (mean 194 ± 193 ng g⁻¹ dw) in sediment and 0.9–47 μg g⁻¹ dw (mean 7.2 ± 10 μg g⁻¹ dw) in zooplankton, whereas OPE concentrations varied between 9 and 1013 ng L⁻¹ (mean 243 ± 327 ng L⁻¹) in seawater, 13–49 ng g⁻¹ dw (mean 25 ± 11 ng g⁻¹ dw) in sediment and 0.4–4.6 μg g⁻¹ dw (mean 1.6 ± 1.0 μg g⁻¹ dw) in zooplankton. Microplastic counts in seawater ranged from 0 to 0.3 items m⁻³ (mean 0.05 ± 0.05 items m⁻³). We observed high fluctuations in contaminant concentrations in zooplankton between different sampling events. However, the smallest zooplankton size class generally exhibited the highest PAE and OPE concentrations. Field-derived bioconcentration factors (BCFs) showed that certain compounds are prone to bioaccumulate in zooplankton, including some of the most widely used chlorinated OPEs, but with different intensity depending on the zooplankton size-class. The concentration of plastic additives in surface waters and the abundance of microplastic particles were not correlated, implying that they are not necessarily good indicators for each other in this compartment. This is the first comprehensive study on the occurrence and temporal variability of PAEs and OPEs in the coastal Mediterranean based on the parallel collection of water, sediment and differently sized zooplankton samples.
Показать больше [+] Меньше [-]A semi-qualitative approach to the operationalization of the Food–Environment–Energy–Water (FE²W) Nexus concept for infrastructure planning: a case study of the Niger Basin Полный текст
2021
Seidou, Ousmane | Ringler, Claudia | Kalčić, Špela | Ferrini, Luca | Ramani, Traoré Abdou | Guero, Abdou
The countries sharing the Niger River suffer from poor access to clean water and energy as well as food insecurity. The Niger River Basin Authority is tasked with advancing progress in all these areas while also reducing environmental degradation. To help the basin authority and its investors prioritize portfolio activities that support multiple securities of interest, we developed a mixed-methods approach that engaged basin countries in qualitatively ranking projects to meet energy, environmental and food security goals, complemented by quantitative modelling for the more complex ranking of water and environmental sustainability goals, necessitated by complex upstream–downstream linkages.
Показать больше [+] Меньше [-]Phthalates and organophosphate esters in surface water, sediments and zooplankton of the NW Mediterranean Sea: exploring links with microplastic abundance and accumulation in the marine food web Полный текст
2021
Schmidt, Natascha | Castro-jiménez, Javier | Oursel, Benjamin | Sempéré, Richard
In this study, surface seawater, sediment and zooplankton samples were collected from three different sampling stations in Marseille Bay (NW Mediterranean Sea) and were analyzed for both microplastics and organic plastic additives including seven phthalates (PAEs) and nine organophosphate esters (OPEs). PAE concentrations ranged from 100 to 527 ng L-1 (mean 191±123 ng L-1) in seawater, 12 to 610 ng g-1 dw (mean 194±193 ng g-1 dw) in sediment and 0.9 to 47 μg g-1 dw (mean 7.2±10 μg g-1 dw) in zooplankton, whereas OPE concentrations varied between 9-1013 ng L-1 (mean 243±327 ng L-1) in seawater, 13-49 ng g-1 dw (mean 25±11 ng g-1 dw) in sediment and 0.4-4.6 μg g-1 dw (mean 1.6±1.0 μg g-1 dw) in zooplankton. Microplastic counts in seawater ranged from 0 to 0.3 items m-3 (mean 0.05±0.05 items m-3). We observed high fluctuations in contaminant concentrations in zooplankton between different sampling events. However, the smallest zooplankton size class generally exhibited the highest PAE and OPE concentrations. Field-derived bioconcentration factors (BCFs) showed that certain compounds are prone to bioaccumulate in zooplankton, including some of the most widely used chlorinated OPEs, but with different intensity depending on the zooplankton size-class. The concentration of plastic additives in surface waters and the abundance of microplastic particles were not correlated, implying that they are not necessarily good indicators for each other in this compartment. This is the first comprehensive study on the occurrence and temporal variability of PAEs and OPEs in the coastal Mediterranean based on the parallel collection of water, sediment and differently sized zooplankton samples.
Показать больше [+] Меньше [-]Cold plasma hydrophilization of soy protein isolate and milk protein concentrate enables manufacturing of surfactant-free water suspensions. Part I: Hydrophilization of food powders using cold plasma Полный текст
2021
Bormashenko, Edward | Bormashenko, Yelena | Legchenkova, Irina | Eren, Necla Mine
In this study, we found that treatment with cold plasma influenced the wetting properties of soy protein isolate and milk protein concentrate powders. Cold plasma treatment significantly decreased the apparent contact angle of the powders, indicating hydrophilization of the powders. Cold radiofrequency low-pressure plasma treatment had a larger effect on powder wettability than corona atmospheric plasma discharge. In addition, cold plasma treatment had a more noticeable effect on the wettability of the hydrophobic milk protein concentrate than on the inherently hydrophilic soy protein isolate. Both the soy protein isolate and milk protein concentrate demonstrated zero hydrophobic recovery over time. Scanning electron microscopy showed that cold air plasma treatment of food powders caused minor surface oxidation, though these changes were not observed using FTIR spectroscopy. We suggest that cold plasma treatment has important implications for the production of stabilizer-free food suspensions.
Показать больше [+] Меньше [-]Thermal inactivation kinetics of seven genera of vegetative bacterial pathogens common to the food chain are similar after adjusting for effects of water activity, sugar content and pH Полный текст
2021
van Lieverloo, J. Hein M. | Bijlaart, Mounia | Wells-Bennik, Marjon H.J. | Den Besten, Heidy M.W. | Zwietering, Marcel H.
A predictive model was made for the logarithm of the thermal decimal reduction time (logD) of Salmonella enterica (D = time to 90% reduction by inactivation). The model was fitted with multiple linear regression from 521 logD-values reported in literature for laboratory media and foods highly varying in water activity and pH. The single regression model with temperature as the only variable had a high residual standard error (RSE) of 0.883 logD and no predictive value (fraction of variance explained (R²) < 0.001). Adding water activity, sugar content and pH as predictors resulted in a model with a lower RSE of 0.458 logD and an adjusted R² of 0.73. The model was validated by comparing 985 predicted with observed logD for S. enterica from other publications. The model was subsequently validated with 1498 published logD-values for inactivation of vegetative cells of nine other pathogenic bacteria genera (mainly Listeria monocytogenes, Escherichia coli, Clostridium perfringens, Cronobacter spp., Staphylococcus aureus, Yersinia enterocolitica) in or on a variety of laboratory media, meat, fish, dairy, nuts, fruits and vegetables. Regression analyses for validation with the 985 logD of S. enterica and 2483 logD of all genera show deviations from the expected slope of 1 (both 0.81) and the expected intercept of 0 (0.04 and 0.19 logD respectively). However, only 0.7% and 2% respectively of the new logD (expected: 0.5%) were observed above the 99% prediction interval of the original S. enterica model based on 521 logD. The findings suggest that i) the variability of thermal resistance of strains within species is larger than between genera and species; ii) one generic predictive model, also accounting for variability, suffices for designing the thermal inactivation of a variety of vegetative pathogenic bacteria in many food types.
Показать больше [+] Меньше [-]Thermal inactivation kinetics of seven genera of vegetative bacterial pathogens common to the food chain are similar after adjusting for effects of water activity, sugar content and pH Полный текст
2021
van Lieverloo, Hein M. | Bijlaart, Mounia | Wells-Bennik, Marjon H.J. | Den Besten, Heidy M.W. | Zwietering, Marcel H.
A predictive model was made for the logarithm of the thermal decimal reduction time (logD) of Salmonella enterica (D = time to 90% reduction by inactivation). The model was fitted with multiple linear regression from 521 logD-values reported in literature for laboratory media and foods highly varying in water activity and pH. The single regression model with temperature as the only variable had a high residual standard error (RSE) of 0.883 logD and no predictive value (fraction of variance explained (R2) < 0.001). Adding water activity, sugar content and pH as predictors resulted in a model with a lower RSE of 0.458 logD and an adjusted R2 of 0.73. The model was validated by comparing 985 predicted with observed logD for S. enterica from other publications. The model was subsequently validated with 1498 published logD-values for inactivation of vegetative cells of nine other pathogenic bacteria genera (mainly Listeria monocytogenes, Escherichia coli, Clostridium perfringens, Cronobacter spp., Staphylococcus aureus, Yersinia enterocolitica) in or on a variety of laboratory media, meat, fish, dairy, nuts, fruits and vegetables. Regression analyses for validation with the 985 logD of S. enterica and 2483 logD of all genera show deviations from the expected slope of 1 (both 0.81) and the expected intercept of 0 (0.04 and 0.19 logD respectively). However, only 0.7% and 2% respectively of the new logD (expected: 0.5%) were observed above the 99% prediction interval of the original S. enterica model based on 521 logD. The findings suggest that i) the variability of thermal resistance of strains within species is larger than between genera and species; ii) one generic predictive model, also accounting for variability, suffices for designing the thermal inactivation of a variety of vegetative pathogenic bacteria in many food types.
Показать больше [+] Меньше [-]Simulating and assessing the effects of seasonal fallow schemes on the water-food-energy nexus in a shallow groundwater-fed plain of the Haihe River basin of China Полный текст
2021
Zhang, Xueliang | Ren, Li
The increasing dependency on groundwater, especially in irrigated regions, has highlighted the notable place of groundwater resources within the water-food-energy nexus (WFEN). This role is particularly relevant in the Haihe River basin of China, a globally representative area that is experiencing rapid aquifer depletion. The winter wheat (Triticum aestivum L.) fallow strategy may have the potential to limit withdrawal in this region. Based on information from multiple sources, this paper proposed six kinds of fallow schemes—under the same triple-cropping system consisting of winter wheat and summer maize (Zea mays L.) followed by fallow and summer maize in two years (WW–SM/F–SM) but with different irrigation schemes—as scenarios to conduct detailed simulation by a modified Soil and Water Assessment Tool (SWAT) model. Then, the water balance components of the shallow aquifer and soil profile (2 m) under different scenarios were analyzed to quantify the variations in hydrological processes caused by changes in cropping system and pumping intensity. Furthermore, through 17 indices that could quantitatively describe the changes related to the WFEN, the effects of seasonal fallow schemes on shallow groundwater drawdown mitigation, grain yield reduction, and energy consumption savings were evaluated. Based on these evaluation outcomes, linear programming was used to optimize the fallow schemes at the subbasin scale. As a result, to satisfy the constraint of stopping groundwater drawdown as well as improving water and energy productivities, the minimum reduction in the annual average winter wheat yield would be 55% compared with the basic scenario, while the summer maize yield would remain basically stable. Under the optimized fallow scheme pattern, 66% of the well-irrigated cropland should adopt the WW–SM/F–SM system with two irrigation applications for winter wheat and a rain-fed scheme for summer maize; additionally, 24% of the well-irrigated cropland should adopt the WW–SM/F–SM system with one irrigation application for winter wheat and a rain-fed scheme for summer maize, and the recommended fallow schemes for the other 10% of well-irrigated cropland varied spatially. Compared to the basic scenario, the optimized fallow scheme pattern could decrease shallow groundwater exploitation by 36.5 × 10⁸ m³ a⁻¹ (i.e., to realize shallow groundwater equilibrium), reduce the diesel consumption of agricultural machines and electricity consumption of pumping wells by 32% and 90%, respectively, and save energy costs by approximately 873 yuan ha⁻¹. These results could provide a quantitative reference for policy-making in this watershed and serve as a typical case for similar areas that wish to implement fallow strategies to achieve groundwater sustainability.
Показать больше [+] Меньше [-]Evaluación nutricional de lenteja de agua (Lemna minor) en la alimentación de cuyes (Cavia porcellus) en la etapa de engorde en la provincia Rodríguez de Mendoza, Amazonas-2019 Полный текст
2021
Huaman Vargas, Danitza Milagros | Rabanal Oyarce, Raúl
La investigación tuvo por objetivo evaluar el efecto de lenteja de agua (Lemna minor) en la alimentación de cuyes (Cavia porcellus) en la etapa de engorde en Rodríguez de Mendoza, Amazonas, Se evaluó el consumo de alimento, ganancia de peso, conversión alimenticia y mérito económicos. Para lo cual se formuló tres tratamientos con la adición de Lemna minor en proporción de 5%, 10% y 15% y un grupo control 0%, se utilizaron 64 cuyes en la etapa de engorde, distribuidos en dos grupos hembras y machos de 8 cuyes para cada tratamiento y con un peso promedio inicial de 497 g. El experimento se llevó a cabo por un periodo de 45 días. Se obtuvo que los animales del testigo alcanzaron mayor consumo de alimento en las tres primeras semanas de evaluación, siendo superados por los animales del T3 en las últimas semanas de investigación, en la ganancia de peso el T3 logro mayor ganancia en ambos sexos, se obtuvo una mejor conversión alimenticia en el testigo para los machos y en el T3 para las hembras y la mayor relación beneficio/costo se obtuvo en el tratamiento 3 para los machos y en el testigo para hembras. No se encontró diferencia significativa p>0.05 en ninguno de los parámetros evaluados.
Показать больше [+] Меньше [-]Meeting the challenges of food-energy-water systems in typical mega-urban regions from final demands and supply chains: A case study of the Bohai mega-urban region, China Полный текст
2021
Deng, Caiyun | Wang, Hongrui | Hong, Siyang | Zhao, Weijing | Wang, Cheng
The safety of food-energy-water (FEW) systems in mega-urban regions (MURs) is an urgent issue for achieving regional sustainable development. However, with the rapid growth of the population, the economy and urbanization and uncertainty inherent in climate change and international politics, FEW systems in MURs face tremendous challenges not only because of increasing demands and inadequate resources but also because of the dependence on imports from other regions. Therefore, it is essential to identify the critical connections and change features in FEW systems from economic actions to better meet these challenges. Taking the Bohai MUR as a case study, this study explores FEW changes embodied in trade, final demands and supply chains during 2002–2012 and identifies important nodes and critical supply chains by combining a three-scale input-output (IO) model with structural path analysis (SPA). The results show that FEW flows embodied in trade were significantly increased during the 10 years. The Bohai MUR turned from a net importer to a net exporter in embodied food and energy from 2002 to 2012. In final demands, the ratios of consumption and investment in embodied FEW obviously decreased, but exports increased significantly. Exports were always the largest consumer of embodied FEW, and urban households also consumed them. The top 20 critical supply chains from the final demands to the upstream production sectors for food, energy and water systems in 2002 and 2012 are listed. One and three common routes in the top 5 critical supply chains strongly impact embodied FEW. The common critical routes of each subsystem in time are also identified. Embodied FEW change factors and coping strategies are explored as well. This study will help stakeholders make responsible production and consumption decisions to improve the resilience of FEW systems and achieve sustainable development goals (SDGs) at the mega-urban scale.
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