As the world's population grows, food and energy supply will be one of the most important challenges. Agriculture, as the most important food producer, is not only a consumer of water and energy but also a major supplier of energy. Consequently, a balance must be struck between the harvest and utilization of production resources and the amount of agricultural production. The UN's Third Millennium Goals are on the agenda of achieving sustainable long-term development of human societies and ensuring food, water, and energy availability for future generations. To accomplish these goals, researchers have developed numerous interdisciplinary and specialized frameworks and approaches to achieve a dynamic and optimal balance of production and resource utilization, one of which being water, energy, and food. The water, energy and food Nexus approach is an overall vision of sustainability that strives to balance the various goals, interests, and needs of people and the environment by quantifying water, energy and food relationships through qualitative and quantitative modeling as well as advancing research for Integrate modeling and management to deliver important sustainable development strategies in today's dynamic and complex world. Given the environmental and water crises that threaten the Iranian nation's food and energy security, water, energy, and food, Nexus management can bring about change and balance in different sectors, depending on the needs and participation of all stakeholders. In this paper, a novel model for the Nexus approach governance model using the multi-layer visionary is being developed for the Iranian region for the water and food crisis the country is facing today.

Managers of federal, state, local, and nonprofit organizations around the world are faced with the complex task of managing interconnected systems of scarce resources. One key example of this has been the recent research on the connections between water, energy, and food/agriculture, and the problem of managing these resources to be sustainable and reduce the likelihood of resource depletion. While engineering research has focused on achieving greater efficiencies in resource management, less attention has been given to issues of governance within the fragmented, decentralized, and polycentric systems that are responsible for resource delivery. The central question animating this paper is whether resource management decisions in water, energy, and food are siloed, and what theoretical frameworks can be leveraged to develop strategies to break down existing silos. Results from a survey of water agencies suggests that there is little communication between the water, energy, and food policy areas. If achieving greater nexus requires increased communication and repeated interactions, there is significant work to be done to re-think how policy and management are organized and conducted.

The maintenance of the total natural capital stocks has received increased attention worldwide for its ability to achieve sustainable development. However, the claim that ecosystem services (ES) contribute to sustainability has not been sufficiently verified. In this study, we explore how major ecosystem functions affect food, energy, and water (FEW) sustainability. This research addresses the importance of ecosystems and services provided, which sustainability depends on. Specific types of sustainability – food, energy, water, and fundamental ES with regional GDP are chosen to exam this relationship using the pressure-state-response framework. The results show that ecosystem services are indispensable keys to successfully achieving sustainable development goals. The research findings also illustrate a scheme for emphasizing how economic development can be a factor contributing to a multi-objective case study. Our approach may help guide future cooperative applications to achieve food, energy, and water sustainability while protecting ecosystem services.

Food, energy, and water resources, which are interconnected with one another, are essential to human beings and sustainable development goals. Existing studies have quantified direct interconnections of food, energy, and water (FEW) systems in China but overlooked their indirect and spatial interconnections through production systems of other products. Quantifying both the direct and indirect spatial interconnections of food, energy, and water systems is the basis of holistic FEW resource management. The spatial interconnections of the FEW systems within China’s economic supply chains at the provincial level were quantified from both demand-driven and supply-push perspectives in this study. Results show that food and energy subsystems have tighter coupling relations than the other relationships in the FEW nexus from the demand perspective, and food and water subsystems have tighter coupling relations from the supply perspective. Findings of this study highlight the necessity of demand-side and supply-side measures by identifying critical final consumers and primary suppliers. For example, primary inputs of energy extraction sectors in Inner Mongolia, Shanxi, and Heilongjiang are crucial for national water withdrawals. Sustainable management of FEW resources in China can be better achieved through strengthening the interdepartmental and interregional cooperation from both the demand and supply sides.

Water, Energy and Food (WEF) are key elements of economic and social sustainable development, and present a complex nexus. Existed WEF nexus research is mainly confined to qualitative analyses, and it needs constant improvement and increases quantitative analyses. In China, water security is the most prominent problem in the WEF-nexus, which is manifested in the competitive relationship between food and energy production for water. Therefore, the matter of alleviating water resources stress has become a difficult and hot issue. After improving the existed water footprint accounting method for food and energy production, this study calculated the food water footprints (blue water footprint and green water footprint) in the 31 provinces of mainland China in 2015, as well as the blue water footprints of major energy systems (coal, oil, natural gas and thermal power generation). This study proposed water resources pressure index (IWS), water resources pressure contribution rate of food and energy (WCR), water consumption rate of food and energy (n) and competition composite index (CCI) of WEF, which were used to evaluate the consumption of water resources in food and energy production in different regions, and assess the intensity of competition for water resources in food and energy production. The results showed that the national food water footprint in 2015 was 690.8 Gm³, and the blue food water footprint was 287.8 Gm³. The main water-consuming blue energy water footprint was 18.5 Gm³, and coal production accounted for 9.9% and thermal power generation accounted for 87.6%. According to the competition indicators, the competition relationship among the administrative regions of the 31 provinces in mainland China was obtained. For example, 5 provinces had serious competition and 19 provinces had weak competition. The water consumption of the energy industry continues to grow rapidly by economic development. Corresponding measures should be taken according to the different competition levels for water resources.

In this study, a multi-level interval fuzzy credibility-constrained programming (MIFCP) method is developed for planning the regional-scale water-energy-food nexus (WEFN) system. MIFCP can not only deal with uncertainties expressed as interval parameters and fuzzy sets, but also handle conflicts and hierarchical relationships among multiple decision departments. The MIFCP approach is then applied to planning the WEFN system of Henan Province, China. Solutions of three different decision targets in various hierarchy levels, five scenarios with different decision makers’ objectives and five credibility levels toward different necessity degrees are examined. Several findings in association with various planting structures, water resources demand, energy consumption, fertilizer and pesticide utilizations and system benefits are achieved. Results reveal that the future total irrigation water can decrease by 1.49% from years 2020–2025. Results also disclose that the total cultivated area can change by 1.91% owing to the variation of fertilizer and pesticide change. Compared to single level programming (SLP) and bi-level programming (BP) approaches, the MIFCP-WEFN model can help decision-makers identify the optimal agricultural water resources management schemes by means of the leadership of water resources managers as well as the feedback of two diverse followers (i.e. energy managers and agricultural managers).

Light-emitting diode (LED) technology is an emerging nonthermal food processing technique that utilizes light energy with wavelengths ranging from 200 to 780 nm. Inactivation of bacteria, viruses, and fungi in water by LED treatment has been studied extensively. LED technology has also shown antimicrobial efficacy in food systems. This review provides an overview of recent studies of LED decontamination of water and food. LEDs produce an antibacterial effect by photodynamic inactivation due to photosensitization of light absorbing compounds in the presence of oxygen and DNA damage; however, such inactivation is dependent on the wavelength of light energy used. Commercial applications of LED treatment include air ventilation systems in office spaces, curing, medical applications, water treatment, and algaculture. As low penetration depth and high-intensity usage can challenge optimal LED treatment, optimization studies are required to select the right light wavelength for the application and to standardize measurements of light energy dosage.

Studying trade-offs in the long-term development of water-energy-food systems requires a new family of hydroeconomic optimization models. This article reviews the central considerations behind these models, highlighting the importance of water infrastructure, the foundations of a theory of decision-making, and the handling of uncertainty. Integrated assessment models (IAMs), used in climate change policy research, provide insights that can support this development. In particular, IAM approaches to intertemporal decision-making and economic valuation can improve existing models. At the same time, IAMs have weaknesses identified elsewhere and can benefit from the development of hydroeconomic models, which have complementary strengths.

Resumen: El presente proyecto nace de la necesidad de conocer el funcionamiento de un calentador de agua, así como determinar y describir sus partes integrantes con el propósito de adquirir los conocimientos necesarios para diseñar y proyectar dicho equipo para la producción de electricidad en una Central Térmica. El trabajo fin de grado consta de ocho capítulos y tres anexos (A, B y C) , a continuación resumen los más representativos : 1. Introducción: En este apartado se describe el equipo a presión dentro del ciclo termodinámico y se explica la importancia dentro de este. 2. Objetivos y Alcance: Marca el objetivo fundamental que consiste en la descripción del diseño en base a la normativa vigente. 3. Exposición General de un Feed-Water Heater: En este punto se explica detalladamente cada una de las partes integrantes del equipo a diseñar, a demás de los tipos de calentadores existentes. 4. Descripción del diseño del calentador: Una vez se explican cada una de las partes integrantes del equipo a diseñar, este capitulo se encarga de los siguientes objetivos: a. Situar el equipo dentro del ciclo termodinámico de la central. b. Definir las condiciones de contorno del calentador (temperaturas, presiones, flujos masicos…etc) , es decir , se obtienen todos los parámetros necesarios de partida para poder diseñar el calentador. c. Descripción del diseño térmico que utilizan los programas actuales para diseñar este tipo de equipos en base a la normativa vigente incluyendo formulas, tablas y conocimientos básicos en base a la experiencia para un correcto diseño térmico. d. Descripción del diseño mecánico que utilizan los programas actuales para diseñar este tipo de equipos en base a la normativa vigente incluyendo formulas, tablas y conocimientos básicos en base a la experiencia para una fabricación optima en consonancia con el previo diseño térmico. 5. Resultados del diseño y Anexos B y C: Tras recibir los datos necesarios para diseñar el equipo por parte de la central térmica de costanera mostrados en el anexo B (tablas de datos de la central) , el programa de cálculo térmico realiza el cálculo optimo del equipo dando una tabla de datos como resultado conocida como data sheet, es donde se muestran los parámetros térmicos fundamentales como área de intercambio de cada zona , espesores , materiales…etc. El anexo B también muestra la tabla de datos del diseño mecánico que recoge los espesores mas significativos del equipo según los requerimientos de diseño. El anexo C muestra dos planos característicos del equipo, siendo estos resultados del diseño imprescindibles para la fabricación del mismo. 6. Análisis Económico: Determina los costes y amortización del calentador por parte de la central térmica. 7. Conclusiones: En estas se defiende: a. Materiales Elegidos. b. Coste del calentador de agua de alimentación. | Abstract: This project is born from the need to know the operation of a water heater, as well as determine and describe its integral parts in order to acquire the necessary knowledge to design and project such equipment for the production of electricity in a Thermal Power Plant. The final degree project consists of eight chapters and three annexes (A, B and C), below summarize the most representative: 1. Introduction: This section describes the pressure equipment within the thermodynamic cycle and explains the importance within it: 2. Objectives and Scope: Mark the fundamental objective that consists in the description of the design based on current regulations. 3. General Exhibition of a Feed-Water Heater: This section explains in detail each of the integral parts of the equipment to be designed, in addition to the types of existing heaters. 4. Description of the heater design: Once each of the components of the equipment to be designed is explained, this chapter takes care of the following objectives: a. Place the equipment within the thermodynamic cycle of the plant. b. Define boiler boundary conditions (temperatures, pressures, mass flows ... etc), that is, all necessary starting parameters are obtained to be able to design the boiler. c. Description of the thermal design used by current programs to design this type of equipment based on current regulations including formulas, tables and basic knowledge based on experience for proper thermal design. d. Description of the mechanical design used by current programs to design this type of equipment based on current regulations including formulas, tables and basic knowledge based on experience for optimal manufacturing in line with the previous thermal design. 5. Design results and Annexes B and C: After receiving the necessary data to design the equipment by the waterfront thermal power plant shown in Annex B (data tables of the plant), the thermal calculation program performs the calculation optimum of the equipment giving a data table as a result known as data sheet, is where the fundamental thermal parameters are shown as the exchange area of each zone, thicknesses, materials ... etc. Annex B also shows the mechanical design data table that includes the most significant thicknesses of the equipment according to the design requirements. Annex C shows two characteristic drawings of the equipment, these design results being essential for its manufacture. 6. Economic Analysis: Determines the costs and amortization of the heater by the thermal power plant. 7. Conclusions: These are defended: a. Chosen Materials. b. Feed water heater cost. | Grado en Ingeniería de los Recursos Energéticos

The European Commission asked EFSA to update its previous Opinion on nickel in food and drinking water, taking into account new occurrence data, the updated benchmark dose (BMD) Guidance and newly available scientific information. More than 47,000 analytical results on the occurrence of nickel were used for calculating chronic and acute dietary exposure. An increased incidence of post-implantation loss in rats was identified as the critical effect for the risk characterisation of chronic oral exposure and a BMDL10 of 1.3 mg Ni/kg body weight (bw) per day was selected as the reference point for the establishment of a tolerable daily intake (TDI) of 13 μg/kg bw. Eczematous flare-up reactions in the skin elicited in nickel-sensitised humans, a condition known as systemic contact dermatitis, was identified as the critical effect for the risk characterisation of acute oral exposure. A BMDL could not be derived, and therefore, the lowest-observed-adverse-effect-level of 4.3 μg Ni/kg bw was selected as the reference point. The margin of exposure (MOE) approach was applied and an MOE of 30 or higher was considered as being indicative of a low health concern. The mean lower bound (LB)/upper bound (UB) chronic dietary exposure was below or at the level of the TDI. The 95th percentile LB/UB chronic dietary exposure was below the TDI in adolescents and in all adult age groups, but generally exceeded the TDI in toddlers and in other children, as well as in infants in some surveys. This may raise a health concern in these young age groups. The MOE values for the mean UB acute dietary exposure and for the 95th percentile UB raises a health concern for nickel-sensitised individuals. The MOE values for an acute scenario regarding consumption of a glass of water on an empty stomach do not raise a health concern.