Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas
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GSE4-loaded nanoparticles a potential therapy for lung fibrosis that enhances pneumocyte growth, reduces apoptosis and DNA damage
Full text linkIdiopathic pulmonary fibrosis is a lethal lung fibrotic disease, associated with aging with a mean survival of 2-5 years and no curative treatment. The GSE4 peptide is able to rescue cells from senescence, DNA and oxidative damage, inflammation, and induces telomerase activity. Here, we investigated the protective effect of GSE4 expression in vitro in rat alveolar epithelial cells (AECs), and in vivo in a bleomycin model of lung fibrosis. Bleomycin-injured rat AECs, expressing GSE4 or treated with GSE4-PLGA/PEI nanoparticles showed an increase of telomerase activity, decreased DNA damage, and decreased expression of IL6 and cleaved-caspase 3. In addition, these cells showed an inhibition in expression of fibrotic markers induced by TGF-??such as collagen-I and III among others. Furthermore, treatment with GSE4-PLGA/PEI nanoparticles in a rat model of bleomycin-induced fibrosis, increased telomerase activity and decreased DNA damage in proSP-C cells. Both in preventive and therapeutic protocols GSE4-PLGA/ PEI nanoparticles prevented and attenuated lung damage monitored by SPECT-CT and inhibited collagen deposition. Lungs of rats treated with bleomycin and GSE4-PLGA/PEI nanoparticles showed reduced expression of ??-SMA and pro-inflammatory cytokines, increased number of pro-SPC-
Multicellular structures and increased DNA synthesis in proSP-C cells, indicating therapeutic efficacy of GSE4-nanoparticles in experimental lung fibrosis and a possible curative treatment for lung fibrotic patients
Analysis of alternative frequency control schemes for increasing renewable energy penetration in El Hierro Island power system
Full text linkEl Hierro, island declared as a biosphere reserve by the UNESCO in 2000, aims to become self-sufficient in energy and 100% free of greenhouse gas emissions. This isolated power system consists of diesel units and a hybrid Wind- Pump Storage Hydropower Plant (W-PSHP), equipped with Variable Speed Wind Turbines (VSWTs), Pelton turbines and a pump station with both fixed- and variable-speed pumps. During last years the annual average renewable energy participation is increasing, especially due to the improvements in the frequency control strategies in PSHP including the operation in short circuit mode. This performance involves an important reduction of the system efficiency but allows PSHP to regulate frequency deviations when available wind power is higher than power demand and the Diesel units are disabled. In this paper different alternative frequency control schemes are proposed so that Pelton units support to the frequency control can be substituted, avoiding energy losses owing to short-circuit operation. This way renewable energy participation would be increased. The control schemes are developed using pumping station regulation capacity, the proper kinetic energy of the VSWTs rotors and a new Flywheel Energy Storage System connected to the grid by means of power electronics. Nine different control cases have been presented, including hydraulic short circuit operating mode. Different simulations have been carried out and they confirm that proposed control schemes fulfil the initial research objectives and enable to improve the global energy efficiency of the system
Shedding Light on the Origin of Pb-204, the Heaviest s-Process???Only Isotope in the Solar System
Full text linkAsymptotic giant branch stars are responsible for the production of most of the heavy isotopes beyond Sr observed in the solar system. Among them, isotopes shielded from the r-process contribution by their stable isobars are defined as s-only nuclei. For a long time the abundance of Pb-204, the heaviest s-only isotope, has been a topic of debate because state-of-the-art stellar models appeared to systematically underestimate its solar abundance. Besides the impact of uncertainties from stellar models and galactic chemical evolution simulations, this discrepancy was further obscured by rather divergent theoretical estimates for the neutron capture cross section of its radioactive precursor in the neutron-capture flow, Tl-204 (t1/2 = 3.78 yr), and by the lack of experimental data on this reaction. We present the first ever neutron capture measurement on Tl-204, conducted at the CERN neutron time-of-flight facility n_TOF, employing a sample of only 9 mg of Tl-204 produced at the Institute Laue Langevin high flux reactor. By complementing our new results with semiempirical calculations we obtained, at the s-process temperatures of kT ??? 8 keV and kT ??? 30 keV, Maxwellian-averaged cross sections (MACS) of 580(168) mb and 260(90) mb, respectively. These figures are about 3% lower and 20% higher than the corresponding values widely used in astrophysical calculations, which were based only on theoretical calculations. By using the new Tl-204 MACS, the uncertainty arising from the Tl-204(n,g) cross section on the s-process abundance of Pb-204 has been reduced from ???30% down to +8%/ ???6%, and the s-process calculations are in agreement with the latest solar system abundance of Pb-204 reported by K. Lodders in 2021
Study of air quality due to Madrid Central with Gaussian Processes
Full text linkThis master thesis examines the performance of Gaussian process regression models on air pollution NO2 levels six years before and six years after the implementation of the Madrid Central. The theoretical background is reviewed, including the multivariate Gaussian distribution, stochastic Gaussian processes, and covariance functions. A methodology is presented to analyze the impact of a Low Emission Zone using meteorological data
from the Retiro Park, Plaza del Carmen, and Cuatro Vientos stations. Different models
are evaluated based on the predictive ability using RMSE. The methodology classifies an
event as relevant if the RMSE values increase from one year to another
Curvas IV en diferentes estadios de reparacion
No full textContiene las curvas IV de modulos fotovoltaicos arreglados para el proyecto FOTOVOL3R. Estas curvas corresponden a diferentes estadios de la reparaci??n
The MARES Project: Development of a New Power Take-Off based on a Superconducting Switched Reluctance Machine
Full text linkEst?? accesible s??lo la "author versi??n".In a report published in 2021 by the Bank of America Global Research entitled "To the Moonshots: Future Tech Primer", 14 technologies for the future were listed and analyzed. One item of this list is Oceantech, including harvesting the ocean energies to also produce electricity. The report forecasted that by 2030, the ocean global economy (obviously including much more aspects than solely energy production) will be equivalent to 2010 German GDP, existing a general consensus on the tremendous impact and activity that it may generate in ocean energy generation, including that required for activities associated to the blue economy..
The ocean electric power that can be converted from an ocean planar wave is proporcional to the wave period and to the square of the wave amplitude but, to extract the maximum available power from the wave, the system must be able to be tuned which means having the availability of producing high reactive forces (proportional to its displacement or to its acceleration) which can be even higher than the required active force for producing energy. Consequently, Power Take-Offs (PTO) have always been at the focus of the research, development and innovation in the wave energy sector and they have been one of the main priorities for wave energy during the last years. As a result, the European Commission has funded several projects in recent years addressing its development and optimization under the Horizon 2020 calls, such as OPERA, WaveBoost, WETFEET, IMAGINE and SEA TITAN.
MARES is a recently granted Horizon Project proposing the development of a novel concept for a PTO able to produce the required big forces very efficiently and in a compact way (high energy density) and disregarding permanent magnets-based solutions requiring enormous quantities of rare.earth materials. The use of a simple generator topology (such as a cylindrical switched reluctance machine) and novel superconductors such as HTS or MgB2, make the proposal even more attractive not only for wave energy conversion but also for other applications where very high force density are required.
This paper will first introduce the MARES Project to describe next the conceptual design of the superconducting generator prototype, a machine that will include both technologies of new superconductors and that will be also fabricated and tested by the MARES consortium. The project also includes the implementation analysis of this PTO into two real cases of Wave Energy Converter
Integration of Run-of-River/Pumped Hydro with an Energy Storage System Based on Batteries and Supercapacitors for Enabling Ancillary Services and Extending the Lifetime of Generating Equipment
Full text linkThis chapter explores the integration of run-of-river and pumped-storage
hydroelectric power plants with lithium-ion batteries and supercapacitors to enhance
frequency regulation while minimizing mechanical stress on hydropower units.
Hydroelectric plants play a key role in grid stability, but frequent power adjustments
required for ancillary services accelerate wear and tear on their mechanical compo-
nents. The proposed hybrid system follows a cascading control approach, where each
energy storage element protects the next: lithium-ion batteries handle medium-term
power fluctuations, reducing the need for constant hydro unit adjustments, while
supercapacitors absorb rapid transients, shielding both the batteries and the hydro
units from excessive cycling and mechanical fatigue. This setup improves the effi-
ciency and lifespan of all components while enhancing the plant???s ability to partici-
pate in ancillary service markets. The chapter reviews state-of-the-art solutions and
presents a detailed analysis of technical requirements for hybrid hydropower-storage
systems. It also discusses results from simulations and laboratory tests that validate
the effectiveness of the proposed configuration. Findings indicate that integrating
batteries and supercapacitors with hydropower can significantly improve frequency
regulation quality, extend asset lifespan, and facilitate higher penetration of renew-
able energy sources, making hybrid hydropower systems a crucial component of
future power grid
Superconducting Linear Generators for Wave Energy Converters: A Novel Switched Reluctance Design with Optimized AC Loss Management.
Full text linkEst?? accesible s??lo la "author versi??n".The development of Power Take-Off (PTO) systems is crucial for the progress of wave energy technologies. Among the different PTO concepts, direct-drive systems based on linear electrical generators stand out due to their simplicity, robustness, and efficiency, as they minimize energy transformations. Despite their advantages, linear electrical generators face significant challenges, particularly in terms of force density and reactive power capability. These limitations are most evident at low operational speeds, where high currents are required to generate adequate forces, leading to significant Joule losses. Furthermore, the management of reactive power for implementing advanced control strategies, such as reactive or pseudo-optimal wave energy extraction, is hindered by constant energy dissipation. This is particularly problematic at null or low velocities, where Joule losses persist regardless of speed, limiting the use of reactive power.
Superconducting technology has emerged as a promising solution to these challenges by significantly improving force density while reducing Joule losses. However, the cryogenic systems required for maintaining superconducting conditions impose strict constraints, as all conductor losses, including AC losses associated with oscillating currents, must be minimized. In this context, the paper describes a novel concept for a linear generator based on switched reluctance and superconducting coils, protected under a patented design. To address the issue of AC losses in superconducting cables, we introduce an innovative control strategy for the electronic converter associated with the generator. This strategy is designed to minimize current ripple in the generator phases, reducing oscillation frequencies and, consequently, AC losses.
The proposed approach employs a single-pulse switching strategy, where each phase of the converter is activated and deactivated without intermediate semiconductor switching. This eliminates additional ripple in the phase currents. To regulate the force amplitude, the voltage of the DC link connected to the converter is controlled, enabling precise force modulation.
The paper provides a comprehensive description of the switching strategy and evaluates its performance under oscillatory motion conditions typical of wave energy converters (WECs). A detailed comparison with conventional strategies demonstrates the proposed approach's potential to enhance generator efficiency, reduce losses, and improve overall performance. This work highlights the feasibility of integrating superconducting direct-drive PTO systems into WECs, paving the way for more efficient and reliable wave energy technologie
Proposing a circular economy for mine tailings: using them as catalysts in the treatment of landfill leachate
Full text linkMine tailings (MT), a significant by-product of the mining industry, pose environmental risks due to their metal
content and social hazards when they are located near urban areas. However, their mineral composition, rich in
feldspars, quartz, phyllosilicates, and TiO2, offers potential for reuse within a circular economy framework. In
this context, this study evaluates the catalytic application of MT in a sonophotocatalytic process to treat mature
landfill leachate (LL), a recalcitrant effluent with low biodegradability. Using a full factorial design, the effects of
catalyst load, hydrogen peroxide concentration, and pH of the solution on the removal of total organic carbon
(TOC), Chemical Oxygen Demand and aromatic compounds (Abs254) of the landfill leachate were assessed.
Optimal conditions (2000 mg/L MT, 3000 mg/L H2O2, pH 3) led to 29.8 % and 50.2 % removal of TOC and
aromatic compounds, respectively. Under these optimized physicochemical conditions applied for 3 h of treatment,
the removal of TOC, COD, and aromatic compounds was 84.9 %, 69.6 %, and 88.7 %, respectively.
The biodegradability of treated landfill leachate improved significantly, exceeding 80 % in the Zahn-Wellens
test, with no detectable leaching of metals from the catalyst. These findings demonstrate the feasibility of
repurposing MT as photocatalysts for landfill leachate treatment, offering a sustainable solution to two pressing
waste streams
MedProgramme ??? Child Project 1.1 Reducing Pollution from Harmful Chemicals and Wastes in Mediterranean Hotspots and Measuring Progress to Impacts PCB disposal, Its prioritization, and capacity-building for mercury
Full text linkParticipaci??n como experto representando al CIEMAT, para generar una capacitaci??n en el ??rea del mercurio con el fin de facilitar los estudios de caracterizaci??n del mercurio en un escenario y su eliminaci??n final dentro del marco del MedProgrammeChild Project 1.1. deals with the disposal and prevention of Persistent Organic Pollutants (POPs) and mercury (Hg) in the participating countries of Algeria, Albania, Bosnia & Herzegovina, Lebanon, Montenegro, Morocco, and Tunisia. Output 1.1 aims to manage and dispose of 2,000 tonnes of POPs, and Output 1.2 aims to manage and safely storage of 50 tonnes of mercury wastes.
This meeting focuses on the PCB disposal strategy, including the next procurement exercises, and on capacity-building for mercury to facilitate mercury characterization studies under the MedProgramme and final disposal of mercury.
1.PCBs inventories and PCB disposal phases under the MedProgramme, including prioritization,
2.Capacity-building on Minamata Convention, mercury characterization and mercury disposal (led by CIEMAT