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النتائج 121 - 130 من 372
Planning water-food-ecology nexus system under uncertainty: Tradeoffs and synergies in Central Asia النص الكامل
2022
Ma, Y. | Li, Y.P. | Huang, G.H. | Zhang, Y.F. | Liu, Y.R. | Wang, H. | Ding, Y.K.
Vicious competition for limited water resources hinders the synergetic and sustainable development of Central Asian countries, which further threatens food security and exacerbates ecological degradation. In this study, a copula-based bi-level decentralized programming (CBDP) method is developed and applied to planning water-food-ecology (WFE) nexus system. CBDP has advantages in balancing tradeoffs between different decision levels, analyzing synergies among multiple managers and reflecting joint risks of interrelated uncertain parameters. Then, a CBDP-WFE model is formulated for Central Asia, where the upper-level model aims to maximize system benefit for the region (i.e. regional-scale), and the lower-level model involves five objectives to maximize five countries’ benefits (i.e. national-scale) respectively. Totally 108 scenarios are designed to analyze the impacts of joint constraint-violation risk, agricultural irrigation efficiency, and ecological water demand. Results reveal that (i) improving agricultural irrigation efficiency can optimize the water allocation pattern as well as increase the system benefit; (ii) in order to restore the regional eco-environment, the proportion of ecological water allocation should increase from 7% (of the current level) to 14.9–23.8% (by 2050); (iii) water allocations to Uzbekistan and Tajikistan should be properly controlled especially when available water is scarce. The results are helpful for managers in not only making decisions of water allocation among multiple users and countries but also gaining insight into synergetic management of WFE nexus under various system conditions.
اظهر المزيد [+] اقل [-]Comprehensive Evaluation of Water–Energy–Food System Security in the China–Pakistan Economic Corridor النص الكامل
2022
Cao, Mengzhu | Chen, Yaning | Duan, Weili | Li, Yaqi | Qin, Jingxiu
The safety of the water–energy–food (WEF) system in the China–Pakistan Economic Corridor (CPEC) is critical to the sustainable development of resources, the economy, and society in the region. This paper uses the projection pursuit model of a real-code accelerated genetic algorithm (RAGA-PP) to comprehensively evaluate the WEF system security of the CPEC for the period 2000–2016. The results show that from 2000 to 2016, the projection value of the WEF system was reduced from 2.61 to 0.53, and the overall system security showed a downward trend. Moreover, the CPEC increased by 6.13 × 10⁷ people, resulting in a rapid decrease in per capita water resources and decreased security of the water resources subsystem. With the rising social and economic development in recent years, the per capita energy consumption has likewise risen, leading to a decline in the energy subsystem. At the same time, the per capita grain output in the study area has increased from 185 to 205 kg, and the safety of the food subsystem has been enhanced. However, the significant increase in irrigated areas (from 1.82 × 10¹⁰ to 1.93 × 10¹⁰ hectares) has further highlighted the contradiction between the supply and demand of surface water resources, and the number of tube wells increased by 7.23 × 10⁵, resulting in the consumption of a large amount of electricity and diesel resources. The water–energy (WE) subsystem also became less safe. With the implementation of water resources management policies over the past few decades, the proportion of agricultural water consumption dropped from 95.06% in 2000 to 93.97% in 2016, and the safety of the water–food (WF) subsystem increased. Unfortunately, agricultural irrigation consumes a large amount of power resources, leading to a reduction in the security of the energy–food (EF) subsystem. The research results from the present study could provide a scientific basis for the coordinated development of WEF systems across the CPEC region.
اظهر المزيد [+] اقل [-]Plasma-Activated Acidic Electrolyzed Water: A New Food Disinfectant for Bacterial Suspension and Biofilm النص الكامل
2022
Yaping Heng | Ming Wang | Hongwei Jiang | Shumin Gao | Jin Zhang | Jinlin Wan | Tingji Song | Zhandong Ren | Yuchan Zhu
Food-borne diseases are widespread all over the world, and food safety has attracted much attention. This study is the first to use plasma to activate acidic electrolyzed water (AEW) to obtain a new disinfectant for food processing. The germicidal efficacy of plasma-activated acidic electrolyzed water (PA-AEW) on B. subtilis suspension and biofilm was investigated. Furthermore, the synergistic effect of different bactericidal factors was inferred by investigating the physicochemical parameters of PA-AEW and the influencing factors of bactericidal effect. The results demonstrate that PA-AEW is a highly effective and rapid disinfectant. The killing logarithm (KL) value of PA-AEW on B. subtilis suspension could reach 2.33 log10CFU/mL with a sterilization time of 10 s, which is significantly higher than that of AEW (KL = 0.58 log10CFU/mL) and plasma-activated water (PAW) (KL = 0.98 log10CFU/mL) (significant difference, p <: 0.01). Moreover, the KL value of the B. subtilis biofilm of PA-AEW was 2.41 log10CFU/mL, better than that of PAW and AEW (significant difference, p <: 0.01), indicating that PA-AEW has important application prospects in food processing. The synergistic effect should come from the interaction between reactive chlorine species (RCS) and reactive oxygen and nitrogen species (RONS) in PA-AEW.
اظهر المزيد [+] اقل [-]Analysis of the Complexities in the Water-Energy-Food Nexus: Ghana's Bui Dam Experience النص الكامل
2022
Pius Siakwah | Obodai Torto
The quest to improve the mired development challenges of developing economies at a global scale have in recent years constituted policy imprimatur of development discourse, including the role of national and local resources. “Nexus” is an ultra-prioritized integrative global development approach. It denotes connection(s) linking two or more phenomena or variables. It is therefore not surprising to witness of-the-moment approaches such as the development-security nexus, migration-development-security nexus, and water-energy nexus, among others. Particularly relevant to this article is the water-energy-food (WEF) nexus as an integrative strategy to tackle prosaic issues of industrialization, poverty reduction, food security, and ecological sustainability. Adopting a qualitative methodological approach, the article studies the Bui dam to elucidate how the nexus operates in a complex and tense environment. The central argument is that most analyses of WEF interventions, particularly from the mainstream development literature rarely interrogate complex politics of interest amongst the trident sectors (water, energy, and food). The dominant studies tend to dwell on the technical or instrumental aspects. But an understanding of the complex relationships at play needs a critical approach. Our key argument is that the WEF nexus is prominently embedded in complex historical systems that tend to counter-balance the hyper-deductive projected costs and benefits. It is critical to view the relations amongst the WEF from a non-linear and realistic perspective. WEF as an embodiment of a complex system helps us to understand the multi-level, contradictory, and diverse interests at play within, between, and across the systems. Even though the nexus operations on an assumption of seamless collaborative relations among and between institutions, agencies, and actors in the policy and program implementation space, an analysis of the Bui project in Ghana shows tensions, side-lining, and inter-role conflicts among the actors, where the energy sector actors weigh power and resources over other institutions and actors in the space to drive the nexus.
اظهر المزيد [+] اقل [-]Access to health services, food, and water during an active conflict: Evidence from Ethiopia النص الكامل
2022
Abay, Kibrom A.; Abay, Mehari Hiluf; Berhane, Guush; Chamberlin, Jordan; Croke, Kevin; Tafere, Kibrom | https://orcid.org/0000-0003-1451-2421 Abay, Kibrom; http://orcid.org/0000-0002-1947-9483 Berhane, Guush
Civil conflict began in Ethiopia in November 2020 and has reportedly caused major disrup tions in access to health services, food, and related critical services, in addition to the direct impacts of the conflict on health and well-being. However, the population-level impacts of the conflict have not yet been systematically quantified. We analyze high frequency phone surveys conducted by the World Bank, which included measures of access to basic ser vices, to estimate the impact of the first phase of the war (November 2020 to May 2021) on households in Tigray. After controlling for sample selection, a difference-in-differences approach is used to estimate causal effects of the conflict on population access to health services, food, and water and sanitation. Inverse probability weighting is used to adjust for sample attrition. The conflict has increased the share of respondents who report that they were unable to access needed health services by 35 percentage points (95% CI: 14–55 pp) and medicine by 8 pp (95% CI:2–15 pp). It has also increased the share of households unable to purchase staple foods by 26 pp (95% CI:7–45 pp). The share of households unable to access water did not increase, although the percentage able to purchase soap declined by 17 pp (95% CI: 1–32 pp). We document significant heterogeneity across popula tion groups, with disproportionate effects on the poor, on rural populations, on households with undernourished children, and those living in communities without health facilities. These significant disruptions in access to basic services likely underestimate the true bur den of conflict in the affected population, given that the conflict has continued beyond the survey period, and that worse-affected households may have higher rates of non-response. Documented spatial and household-level heterogeneity in the impact of the conflict may help guide rapid post-conflict responses. | PR | IFPRI3; 5 Strengthening Institutions and Governance | DSGD
اظهر المزيد [+] اقل [-]On the role of water resources management to transform water, energy, food and ecosystem (WEFE) systems in transboundary river basins [Abstract only] النص الكامل
2022
Uhlenbrook, Stefan | Ringler, Claudia | Lautze, Jonathan F. | McCartney, Matthew P. | Hafeez, Mohsin
The program NEXUS Gains addresses key challenges of transforming water, energy, food and ecosystem (WEFE) systems in transboundary bread-basket basins in East and Southern Africa (Blue Nile and Limpopo basins), Central (Aral Sea basin) and South Asia (Ganges and Indus basin) in a changing world. The program particularly explores water resource management options to understand WEFE system interdependencies, trade-offs and synergies and develop more sustainable development pathways for all members society. The presentation will discuss alternative interventions to increase water productivity different sectors (irrigation, forestry, industries) across scales ranging from farm to watershed to river basin scales. Therefore, particular attention will be given to integrated water storage management in human built and natural infrastructure in South Asia and East Africa. The implications for hydrological process and water resources dynamics and wider environmental, social and economic systems are analyzed and related policy implications are discussed considering also climate change.
اظهر المزيد [+] اقل [-]On the role of water resources management to transform water, energy, food and ecosystem (WEFE) systems in transboundary river basins [Abstract only]
2022
Uhlenbrook, Stefan | Ringler, C. | Lautze, Jonathan | McCartney, Matthew | Hafeez, Mohsin
Performance evaluation of high-temperature heat pump systems for hot water and steam generation in food processing | Performance evaluation of high-temperature heat pump systems for hot water and steam generation in food processing النص الكامل
2022
Ren, Shuai | Ahrens, Marcel Ulrich | Hafner, Armin | Widell, Kristina Norne
A large amount of fossil fuels is consumed for hot water and steam generation in food processes such as smoking, scalding, drying, pasteurization, sterilization, cleaning, and cooking, which currently rises both economic- and environmental concerns. At the same time, there is a considerable number of low-grade waste heat available, often from associated cooling processes. High-temperature heat pumps (HTHPs) are considered as a promising solution for steam boilers replacement and waste heat recovery owing to their high energy efficiency and sustainability. In the present study, the performance of three heat pump systems — a trans-critical CO2 heat pump system, a cascade propane-butane heat pump system and an ammonia-water absorption-compression heat pump (ACHP) system, for hot water and steam production in food processing is evaluated based on different application scenarios. In all the scenarios and temperature lift levels, the ACHP exhibits the best thermal performance with moderate pressure levels and low-pressure ratios. When applying the ACHP for both the cleaning and cooking processes, the achievable energy saving rate can reach 79%. Further, the optimal HTHP system architectures for different application scenarios are discussed. | acceptedVersion
اظهر المزيد [+] اقل [-]Hydrothermal processing of microalgal biomass: Circular bio-economy perspectives for addressing food-water-energy nexus النص الكامل
2022
Behera, Bunushree | Mari Selvam, S | Balasubramanian, Paramasivan
Hydrothermal processing of microalgae is regarded as a promising technology to generate multitude of energy based and value-added products. The niche of hydrothermal technologies is still under infancy in terms of the technical discrepancies related to research and development. Thus, the present review critically surveyed the recent advancements linked to the influencing factors governing the algal hydrothermal processing in terms of the product yield and quality. The sustainability of hydrothermal technologies as a standalone method and in broader aspects of circular bio-based economy for energy and value-added platform chemicals are comprehensively discussed. Process optimization and strategic integration of technologies has been suggested to improve efficiency, with reduced energy usage and environmental impacts for addressing the energy-food-water supply chains. Within the wider economic transition and sustainability debate, the knowledge gaps identified and the research hotspots fostering future perspective solutions proposed herewith would facilitate its real-time implementation.
اظهر المزيد [+] اقل [-]Desalted duck egg white nanogels as Pickering stabilizers for food-grade oil-in-water emulsion النص الكامل
2022
Zhao, Jingyun | Guo, Xiaohan | Chen, Ze | Dai, Yalei | Liang, Hongshan | Deng, Qianchun | Li, Shugang | Zhou, Bin
Achieving the reuse of traditional egg by-products, salted duck egg whites (SEW), is an urgent problem to be solved. In this current work, we constructed a heat-induced gel-assisted desalination method for SEW. Subsequently, a top-down way was utilized to prepare desalted duck egg protein nanogels (DEPN) with uniformly distributed diameters and their application in the oil/water (O/W) interface system was explored. The results revealed that the increase of DEPN concentration could lower the droplet size, however, the size was negatively correlated with the oil phase fraction. Moreover, the effect of pH, ionic strength, and temperature on the emulsion stability demonstrated that the DEPN-stabilized emulsion displayed superior physical stability under different conditions. The addition of NaCl resulted in the significant decrease in droplet size of the emulsion, while further increasing the NaCl concentration, the droplet size did not decrease accordingly. Besides, heat-treatment and cold-treatment had little negative effect on the stability of the emulsion. Even if the droplet size of the emulsion increased at 80 °C for 3 h, the morphology of the emulsion remained unchanged. Our study demonstrated DEPN had great potential as a stabilizer for food-grade Pickering emulsions.
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