• Energy Research
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Abstract High power pseudocapacitors are extremely relevant to answer specific needs in the current energy transition arena and to implement an efficient renewable energy society. However, literature shows that are still open gaps concerning improvement of their energy density at high power, conversion efficiency, cost and cycle life. Electrodes based on active transition metal compounds, and in particular metal sulphides, evidence high potential to meet these objectives. This work discusses the dependence on the synthesis route of the charge storage mechanism of manganese sulphide-based materials and relates the pseudocapacitive response of these electrodes with their polycrystalline nature. Results reveal that a manganese oxy-sulphide mixture can achieve a high specific capacitance of 231 F.g−1 at 0.5 A/g in a 0.65 V active window. These values represent a 31.5 % increase compared to pure rambergite, γ-MnS, and 436 % compared to pure hausmannite Mn3O4 prepared under the same conditions. Moreover, the results show that manganese oxy-sulphide electrodes are characterized by good charge retention (73%), and superior long term capacity retention (above 86%) after 5000 cycles, evidencing potential for high power energy storage applications.

<h3>Project Overview</h3> <p>Jurisdictional boundaries of governmental agencies often do not align with the geographic or social boundaries of the policy issues they are tasked with addressing. This spatial mismatch is especially common in relation to natural resources and the environment. Where it occurs, achievement of policy goals may require coordination across jurisdictions, which can lead to mutual benefits. Yet, governmental agencies may view coordination as costly or as leading to a loss of autonomy. This project examined coordination decisions made by local level governmental agencies in California, as they formed Groundwater Sustainability Agencies (GSAs) and subsequently coordinated development of their first groundwater sustainability plans (GSPs) under California's Sustainable Groundwater Management Act (SGMA). The project addresses the question of how agencies make decisions and manage interactions when under a coordination mandate that allots agencies the discretion to decide how to coordinate. More specifically, it investigates:<ol><li>What factors influence decisions regarding the geographic extent of and parties involved in development of new formal agencies for groundwater management,</li><li>How do concerns about the potential risks of coordination affect the choice of coordination mechanisms,</li><li>How does the structure of agency interactions affect their achievement of the objectives of the coordination mandate, and</li><li>How do agencies make sense of a coordination mandate and how does that sense-making process influence the decisions agencies make when deciding how to respond to the mandate?</li></ol></p> <h3>Data Collection Overview</h3> <p>Data were collected between January 2018 and May 2020. The methods for data collection varied by data type.<ul><li>Secondary data on the physical, social, and institutional characteristics of groundwater basins were collected from California Department of Water Resources datasets, the American Community Survey, and the National Land Use Database.</li><li>Data on GSA formation and copies of GSPs and Coordination Agreements were obtained from the California’s SGMA Portal Website (https://sgma.water.ca.gov/portal/)</li><li>Meeting minutes and other documentation were obtained from the respective websites of local-level agencies that formed GSAs.</li><li>Interviews were conducted with representatives from 67 groundwater sustainability agencies. Interviewees spanned 17 of the 19 basins and 38 of the 44 groundwater sustainability plans produced. Interviewees were identified based on formal GSA contact information and selected based on formal notices to produce a GSP. Recruitment sought to interview representatives from least one GSA from each GSP group.</li><li>Participant observation was undertaken of more than 58 public meetings (in person, virtually, or reviewing recordings).</li></ul></p> <h3>Shared Data Organization</h3> <p>The shared data is organized into three folders. A GIS folder contains 16 relevant data files. An interview transcripts folder contains 52 de-identified transcripts from the interviews that were recorded and transcribed. Some interviewees did not agree to recording and transcription of the interviews, thus data from those interviews are not available. A tabular data folder contains 3 spreadsheet workbooks. These include a spreadsheet documenting coordination concerns at the basin-level; a spreadsheet documenting organizational forms and institutions adopted at the basin-level; and a spreadsheet documenting coordination outcomes at the basin-level. Each spreadsheet includes a copy of the codebook used in analyzing the data. This data project also includes 6 documentation files: a GIS metadata workbook, an interview catalog, an interview consent form, a redaction protocol, this data narrative, and an administrative README file.</p> <h3>Data Overview</h3> <p>The research involved a mixed-methods approach that combines information on agencies; the physical, social, and institutional characteristics of groundwater basins and the agencies located within them; formal filings; agreements; and plans developed by agencies; meeting minutes; interview data; and data from participant observation.</p>

This deliverable reports on the main characteristics of the thermal store design, collecting information from previous deliverables in order to define the sensors��� location. In addition, it reports on the integration of the system with the ASTEP components, and some simulations have been done using the UPCT model to verify that the demand of both end users is satisfied. This has covered summer and winter periods and both charging and discharging of the stores.

The world, society and education are constantly evolving, and to respond to these changes, the main governmental institutions have been proposing different global strategies to focus efforts in the same direction. Currently, the United Nations and its 17 Sustainable Development Goals (SDG) have presented a series of indicators that could help to minimise the environmental, economic and social instability we are experiencing. In this sense, Education for Sustainable Development (ESD) has been described as a fundamental factor. Specifically, in previous work, we argued that physical education (PE) could be a good tool to contribute to SDGs. Based on this, no research analysing the voices of Physical Education Teachers (PET) on how this contribution could be made has been identified in previous literature. Therefore, the objectives of this research are: (1) to analyse the voices and opinions of active PETs in terms of the knowledge they have about Sustainable Development (SD); (2) to determine their opinions about the contribution that PE could make to SDGs; and finally, (3) to identify the challenges and limitations of pedagogical action of SD in PE. For this purpose, a qualitative analysis through a semi-structured interview with 41 active PETs was carried out. The main findings will be presented and discussed around four themes: (a) agreement on the concept of sustainability; (b) PE can contribute to the achievement of SDGs; (c) ambiguity in applying SDGs to PE lessons; and (d) teachers’ constraints on how to implement SDGs in PE. It seems to indicate that PETs do not have a multidimensional vision of sustainable development. While they recognise the potential of PE to contribute to SDGs through awareness raising and student learning, they point to its pedagogical and formative constraints as the main barriers to being able to contribute. They pointed to a lack of knowledge on how to do so, guidelines on how to integrate ESD, lack of involvement, shortage of time or resources in school physical education.

It is now environmentally desirable and legally mandatory to add renewable fuels such as ethanol or ethyl tert-butyl ether to gasoline. However, biofuels affect, among other properties, the distillation curve of gasoline, which is subject to strict regulations. This work presents a simple mathematical model capable of accurately predicting the influence that the addition of these oxygenates has on the distillation curve. In order to address this issue, it is essential to find a simple mathematical correlation between the boiling temperatures of the hydrocarbons present in gasoline and the properties (boiling temperature and volume or molar concentration of ethanol) of the corresponding azeotropic mixtures formed with ethanol. Power functions have been assumed to model the temperature composition diagrams of the vapour-liquid equilibrium. Experimental data previously published by these and other authors have been used to fit and validate the model. The results provided by the mathematical model can be of great interest to understand the process of fuel evaporation in spark-ignition engines or the adjustment of distillation cuts in refineries, in order to comply with the regulations, in terms of the distillation curve, after adding ethanol or ethyl tert-butyl ether.

The present paper exhibits a real time assessment of a robust Energy Management Strategy (EMS) for battery-super capacitor (SC) Hybrid Energy Storage System (HESS). The proposed algorithm, dedicated to an electric vehicular application, is based on a self-gain scheduled controller, which guarantees the H∞ performance for a class of linear parameter varying (LPV) systems. Assuming that the duty cycle of the involved DC-DC converters are considered as the variable parameters, that can be captured in real time, and forwarded to the controller to ensure both; the performance and robustness of the closed-loop system. The subsequent controller is therefore time-varying and it is automatically scheduled according to each parameter variation. This algorithm has been validated through experimental results provided by a tailor-made test bench including both the HESS and the vehicle traction emulation system. The experimental results demonstrate the overall stability of the system, where the proposed LPV supervisor successfully accomplishes a power frequency splitting in an adequate way, respecting the dynamic of the sources. The proposed solution provides significant performances for different speed levels.

The most widely used process for hydrogen production is steam methane reforming. It can be carried out using a membrane reactor in which simultaneous hydrogen production and purification occur. Mathematical modeling of these reactors plays a key role in the selection of the design and operating parameters that yield high performance for the reactor. This review study discusses, synthesizes, and compares different mathematical modeling studies on the packed bed membrane reactors for hydrogen production from methane found in the literature. Different approaches used in these modeling studies for the hydrogen permeation steps, reaction kinetic expressions, phases involved (pseudo-homogeneous and heterogeneous), and spatial dimensions (one, two, and three dimensional) are given.

The olive oil mill wastewater (OMW) is a by-product (with a high organic load) derived from the production of the olive oil. The OMW steam reforming (OMWSR) process was studied herein, aiming to decrease the environmental damage of such effluents; simultaneously, the waste is economically and energetically valorized with the H-2 production. Several Ni-containing catalysts were prepared and tested to compare their performances for the OMWSR using a synthetic OMW effluent; still, stability tests were also carried out. The materials were extensively characterized: thermogravimetric analysis, temperature programmed oxidation/reduction, temperature-programmed desorption of CO2/NH3, chemisorption of H-2, inductively coupled plasma optical emission spectrometry and physical adsorption-desorption of N-2 at-196 & DEG;C. Amongst the materials tested, the Ni-Ru/SiO2 sample stood out, exhibiting high catalytic performance: at 400 & DEG;C, the H-2 yield (> 8 mol(H2)& BULL;mol(OMW)(-1)) and conversion of total organic carbon (asymptotic to 75%) were high during all the 24 h of the long-term test, with only a small deactivation being noticed.

Abstract The Mediterranean region is one of the most vulnerable regions to climate change. The majority of climate models forecast a rise in temperatures and less rainfall, which have been observed in recent decades. These changes will affect several vegetation properties, especially phenological dynamics and traits, by increasing drought intensity and recurrence. In this climate change context, the present study aims to assess the evolution of vegetation state and its relation with the climate dynamics in the Mediterranean forest region of northeast Tunisia using Land Surface Phenology (LSP) metrics and the vegetation index (NDVI) analysis from 2000 to 2017. To conduct this work, we used precipitation and temperature data from the two closest weather stations and 16-day NDVI composite images from the MODIS satellite source, with 250-m spatial resolution. Three phenological metrics— start of season (SOS), end of season (EOS), and length of season (LOS) — were obtained and compared for different vegetation types. The LSP variation in response to climatic metrics was also analyzed. The results showed that the LSP in our study area changed significantly during the 2000–2017 period, which includes an average 7.8 days delay in the SOS, an average advance in the EOS by 5 days, and LOS shortened by an average 12.8 days. Autumn (Pr_9) and spring (Pr_3 and P3_4) precipitations, as well as maximum temperature (Tx9+10), represent the best climate parameters to explain the changes in LSP. Both the NDVI and SPEI showed a significant high correlation (p