Desenvolupament embrionari i fotosíntesi en mans d'un sol gen

Un grup d'investigació del CRAG ha descobert que un gen d'Arabidopsis thaliana codifica per a dues proteïnes essencials, una per a la fotosíntesi i una altra per al desenvolupament embrionari. Ara analitzarà si aquest mecanisme es dóna també en altres espècies d'interès agronòmic, perquè podria ajudar a millorar la qualitat de les llavors o el creixement de les plantes.Un grupo de investigación del Centro de Investigación en Agrigenòmica (CRAG) ha descubierto que un gen de Arabidopsis thaliana codifica para dos proteínas esenciales, una para la fotosíntesis y otra para el desarrollo embrionario. Ahora analizará si este mecanismo se da también en otras especies de interés agronómico, porque podría ayudar a mejorar la calidad de las semillas o el crecimiento de las plantas.A research group from CRAG discovers that one gene from Arabidopsis thaliana encodes for two essential proteins, one necessary for photosynthesis and another one necessary for embryo development. The next step for the research team will be to analyze if this mechanism is replicated in species of agronomic interest, which it could have a great impact in improving seed quality and plant growth

Intelligent flexibility management for prosumers

Emission of greenhouse gases and their effects on climate change have become a matter of serious concern all over the world. In addition, electricity demand is expected to increase in the upcoming years. This growth comprises the construction of new power plants, resulting in additional costs on the price of electricity. Due to what is been exposed before, a new way to manage and generate electricity is needed. Recent researches have provided the tools for modernizing the traditional electricity grid into a smart one, which main objective is to coordinate an ever-growing number of intelligent de- vices, each with their own objectives and value perspectives, into a resilient, secure, and ef- ficient system. Here is were the flexibility concept plays an important role in the upcoming energy transition, understanding flexibility as the ability to change certain previously defined parameters in order to fit new requirements. This Master Thesis focuses on the prosumer flexi- bility concept, quantifying his flexibility potential. This flexibility is used to minimize the total expected costs of each prosumer individually, thus reducing their electricity bills. The method- ology developed consists in a Home Energy Management System (HEMS) that will manage automatically that flexibility in order to benefit the end user by minimizing its electrical bill, where the comfort is also taken into account. The results show that it is possible to reduce the electricity invoice by managing optimally the flexibility from loads, batteries, photovoltaic generation and electric vehicles charging points

Grafeno epitaxial en metales de transición: estudio mediante microscopía y espectroscopia de efecto túnel

Tesis doctoral inédita. Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Física de la Materia Condensada . Fecha de lectura: 15-10-201

Periodic spatial variation of the electron-phonon interaction in epitaxial graphene on Ru(0001

We have performed low temperature scanning tunnelling spectroscopy (STS) measurements on graphene epitaxially grown on Ru(0001). An inelastic feature, related to the excitation of a vibrational breathing mode of the graphene lattice, was found at 360 meV. The change in the differential electrical conductance produced by this inelastic feature, which is associated with the electron-phonon interaction strength, varies spatially from one position to other of the graphene supercell. This inhomogeneity in the electronic properties of graphene on Ru(0001) results from local variations of the carbon-ruthenium interaction due to the lattice mismatch between the graphene and the Ru(0001) lattices.Comment: 6 Pages, 3 figure

Centralized flexibility services for distribution system operators through distributed flexible resources

Under the context of smart grids within smart cities, increasing distributed generation, consumer empowerment and emerging flexibility services, distribution system operators could benefit by activating flexibility in distribution grids to avoid deploying new infrastructures and grid overloading. The solution offered by this work is an energy management system algorithm capable of activating flexibility behind the prosumer main meter during constrained periods. Therefore, the distribution system operator could compensate grid congestion during high consumption or production periods and increase their renewable generation hosting capacity by using behind-the-meter flexibility during peak production periods.Postprint (published version

Profitability analysis on demand-side flexibility: A review

Flexibility has emerged as an optimal solution to the increasing uncertainty in power systems produced by the continuous development and penetration of distributed generation based on renewable energy. Many studies have shown the benefits for system operators and stakeholders of diverse ancillary services derived from demand-side flexibility. Cost-benefit analysis on these flexibility services should be carried out to determine the profitable applications, as well as the required adjustments on energy market, price schemes and normative framework to maximize the positive impacts of the available flexibility. This paper endeavors to review the main topics, variables and indexes related to the profitability analysis on demand-side flexibility, as well as the influence of energy markets, pricing and standards on revenue maximization. The conclusions drawn from this review demonstrate that the profitability of flexibility services considerably de-pends on energy market structure, involved assets, electricity prices and current ancillary services remuneration.Peer ReviewedPostprint (published version

Electronic and Geometric Corrugation of Periodically Rippled, Self-nanostructured Graphene Epitaxially Grown on Ru(0001)

Graphene epitaxially grown on Ru(0001) displays a remarkably ordered pattern of hills and valleys in Scanning Tunneling Microscopy (STM) images. To which extent the observed "ripples" are structural or electronic in origin have been much disputed recently. A combination of ultrahigh resolution STM images and Helium Atom diffraction data shows that i) the graphene lattice is rotated with respect to the lattice of Ru and ii) the structural corrugation as determined from He diffraction is substantially smaller (0.015 nm) than predicted (0.15 nm) or reported from X-Ray Diffraction or Low Energy Electron Diffraction. The electronic corrugation, on the contrary, is strong enough to invert the contrast between hills and valleys above +2.6 V as new, spatially localized electronic states enter the energy window of the STM. The large electronic corrugation results in a nanostructured periodic landscape of electron and holes pockets.Comment: 16 pages, 6 figure

Identifying substitutional oxygen as a prolific point defect in monolayer transition metal dichalcogenides with experiment and theory

Chalcogen vacancies are considered to be the most abundant point defects in two-dimensional (2D) transition-metal dichalcogenide (TMD) semiconductors, and predicted to result in deep in-gap states (IGS). As a result, important features in the optical response of 2D-TMDs have typically been attributed to chalcogen vacancies, with indirect support from Transmission Electron Microscopy (TEM) and Scanning Tunneling Microscopy (STM) images. However, TEM imaging measurements do not provide direct access to the electronic structure of individual defects; and while Scanning Tunneling Spectroscopy (STS) is a direct probe of local electronic structure, the interpretation of the chemical nature of atomically-resolved STM images of point defects in 2D-TMDs can be ambiguous. As a result, the assignment of point defects as vacancies or substitutional atoms of different kinds in 2D-TMDs, and their influence on their electronic properties, has been inconsistent and lacks consensus. Here, we combine low-temperature non-contact atomic force microscopy (nc-AFM), STS, and state-of-the-art ab initio density functional theory (DFT) and GW calculations to determine both the structure and electronic properties of the most abundant individual chalcogen-site defects common to 2D-TMDs. Surprisingly, we observe no IGS for any of the chalcogen defects probed. Our results and analysis strongly suggest that the common chalcogen defects in our 2D-TMDs, prepared and measured in standard environments, are substitutional oxygen rather than vacancies

Centralised and distributed optimization for aggregated flexibility services provision

© 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other worksThe recent deployment of distributed battery units in prosumer premises offer new opportunities for providing aggregated flexibility services to both distribution system operators and balance responsible parties. The optimization problem presented in this paper is formulated with an objective of cost minimization which includes energy and battery degradation cost to provide flexibility services. A decomposed solution approach with the alternating direction method of multipliers (ADMM) is used instead of commonly adopted centralised optimization to reduce the computational burden and time, and then reduce scalability limitations. In this work we apply a modified version of ADMM that includes two new features with respect to the original algorithm: first, the primal variables are updated concurrently, which reduces significantly the computational cost when we have a large number of involved prosumers; second, it includes a regularization term named Proximal Jacobian (PJ) that ensures the stability of the solution. A case study is presented for optimal battery operation of 100 prosumer sites with real-life data. The proposed method finds a solution which is equivalent to the centralised optimization problem and is computed between 5 and 12 times faster. Thus, aggregators or large-scale energy communities can use this scalable algorithm to provide flexibility services.Peer ReviewedPostprint (published version