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The ‘4 per mille Soils for Food Security and Climate’ was launched at the COP21 with an aspiration to increase global soil organic matter stocks by 4 per 1000 (or 0.4 %) per year as a compensation for the global emissions of greenhouse gases by anthropogenic sources. This paper surveyed the soil organic carbon (SOC) stock estimates and sequestration potentials from 20 regions in the world (New Zealand, Chile, South Africa, Australia, Tanzania, Indonesia, Kenya, Nigeria, India, China Taiwan, South Korea, China Mainland, United States of America, France, Canada, Belgium, England & Wales, Ireland, Scotland, and Russia). We asked whether the 4 per mille initiative is feasible for the region. The outcomes highlight region specific efforts and scopes for soil carbon sequestration. Reported soil C sequestration rates globally show that under best management practices, 4 per mille or even higher sequestration rates can be accomplished. High C sequestration rates (up to 10 per mille) can be achieved for soils with low initial SOC stock (topsoil less than 30 t C ha− 1), and at the first twenty years after implementation of best management practices. In addition, areas which have reached equilibrium will not be able to further increase their sequestration. We found that most studies on SOC sequestration only consider topsoil (up to 0.3 m depth), as it is considered to be most affected by management techniques. The 4 per mille number was based on a blanket calculation of the whole global soil profile C stock, however the potential to increase SOC is mostly on managed agricultural lands. If we consider 4 per mille in the top 1m of global agricultural soils, SOC sequestration is between 2-3 Gt C year− 1, which effectively offset 20–35% of global anthropogenic greenhouse gas emissions. As a strategy for climate change mitigation, soil carbon sequestration buys time over the next ten to twenty years while other effective sequestration and low carbon technologies become viable. The challenge for cropping farmers is to find disruptive technologies that will further improve soil condition and deliver increased soil carbon. Progress in 4 per mille requires collaboration and communication between scientists, farmers, policy makers, and marketeers.

In order to reduce production costs and environmental impact of bioethanol from sugar beet low purity syrup 2, an intensification of the industrial alcoholic fermentation carried out by Saccharomyces cerevisiae is necessary. Two fermentation processes were tested: multi-stage batch and fed-batch fermentations with different operating conditions. It was established that the fed-batch process was the most efficient to reach the highest ethanol concentration. This process allowed to minimize both growth and ethanol production inhibitions by high sugar concentrations or ethanol. Thus, a good management of the operating conditions (initial volume and feeding rate) could produce 15.2% (v/v) ethanol in 53 h without residual sucrose and with an ethanol productivity of 2.3 g L h−1.

[ES]Se ha elaborado una nueva base de datos de precipitaciones medias mensuales y temperaturas máximas y mínimas medias mensuales, con la que se han analizado los datos de 142 estaciones meteorológicas obtenidos de la Agencia Estatal de Meteorología (AEMET) para el periodo (1989-2018). En este estudio se presentan los resultados de diferentes pruebas de homogeneización y relleno de 134, 172 y 176 series de temperaturas y precipitaciones provenientes de las estaciones ubicadas en la región de Extremadura. Para ello, se realizó un primer control de calidad de los datos cumpliendo con los requisitos de la Organización Meteorológica Mundial (OMM) y las recomendaciones indicadas por el Real Instituto Meteorológico de los Países Bajos (KNMI). Posteriormente se llevó a cabo la homogeneización de las series utilizando el software Climatol, en el que se han implementado diferentes funciones que permiten depurar los datos a través de un análisis de los valores atípicos y de la homogeneidad, así como la completación de las lagunas de las series. Los análisis confirman la obtención de unos niveles de depuración de los datos muy altos, confiables y de buena calidad; obteniendo así una nueva base de datos para posteriores estudios climáticos. [EN]A new database of monthly average rainfall and monthly average maximum and minimum temperatures has been developed, with which data from 142 weather stations obtained from the Agencia Estatal de Meteorología (AEMET) for the period (1989-2018) have been analysed. This study presents the results of different homogenisation and backfilling tests of 134, 172 and 176 temperature and precipitation series from stations located in the region of Extremadura. For this purpose, a first quality control of the data was carried out in compliance with the requirements of the World Meteorological Organisation (WMO) and the recommendations indicated by the Royal Netherlands Meteorological Institute (KNMI). Subsequently, the series were homogenised using Climatol software, in which different functions have been implemented to clean the data through an analysis of outliers and homogeneity, as well as filling in the gaps in the series. The analyses confirm the achievement of very high, reliable and good quality data cleaning levels, thus obtaining a new database for further climate studies. Esta investigación fue financiada por la Junta de Extremadura y el Fondo Europeo de Desarrollo Regional (FEDER) a través de la ayuda al grupo de investigación Alcántara (TIC008), GR21006, y el Proyecto IB18001 “Análisis y modelización del impacto del cambio climático sobre la distribución de zonas vitícolas en Extremadura”. Ponencia presentada en: XII Congreso de la Asociación Española de Climatología celebrado en Santiago de Compostela entre el 19 y el 21 de octubre de 2022.

Flare stacks are a key element in the safety of petrochemical and refinery industries; the correct operating conditions thereof must be ensured through a schedule for the periodic reviewing of all parts thereof. Advances in Non-Destructive Testing (NDT) in recent years and the application thereof to this field allow reliable, objective information to be obtained. This article describes and groups together the main applicable NDT techniques, analysing their advantages and disadvantages, updated with the new possibilities offered by unmanned aircraft or drones.

The work in this research thesis presents a contribution to voltage regulation in electrical networks. By considering adequate active and reactive powers injection into the grid, voltage control and load balancing are provided. These powers are generated from a grid connected renewable energy conversion system : a special attention was paid to the Wind Energy ConversionSystem (WECS) based on Doubly-Fed Induction Generator (DFIG).The typical control strategy for WECS is the maximum power coefficient tracking method. However, this method limits desirable ancillary power services, such as the participation of wind turbines in voltage regulation in the power grid. Therefore, a new method that derives the optimal power coefficient enhancing the participation of WTS in voltage regulation in the network (reactive and unbalanced power compensation), has been developed. The multilevel NPC (Neutral Point Clamped) converter, used for grid interface connection of renewable energy sources systems, has been studied. A predictive control method for the three-level NPC converter, capable of simultaneously compensating the problems of : DC link capacitors voltage balancing, load balancing and power factor correction in the power system, has been proposed. Then, the application of this predictive control was extended to simultaneously achieve multiple objectives: load balancing with power factor correction in the network, DC link capacitors voltage balancing, switching losses minimization and common mode voltage reduction. The switching losses minimization was obtained by proposing a new strategy which consists on exploiting the manufacturer datasheets that gives the evolution of the switching loss energy in function of the circulating current. The experimental curves of the datasheet are expressed in a mathematical model implemented in the predictive control. Simulation and experimental results are presented to evaluate the performance of the proposed method. ; Le travail de cette thèse apporte une contribution aux méthodes de ...

Spinel LiNi0.5Mn1.5O4 as one of the high-energy positive electrode materials for next generation Li-ion batteries has attracted significant interest due to its economic and environmental advantages. However, the sensitivity of this type of material upon short to long term ambient storage conditions and the impact on the electrochemical performances remains poorly explored. Nevertheless, this remains an important aspect for practical large-scale synthesis, storage and utilization. Herein, we study and compare the evolution of surface chemistry, bulk crystal structure and elemental content evolution and distribution of LiNi0.5Mn1.5O4 using a variety of characterization techniques including XPS and STEM-EDS-EELS, as well as electrochemical analysis. We show that Mn species dominate the outer surface (0–5 nm), while Ni and Li are preferentially located further away and in the bulk. The studied LiNi0.5Mn1.5O4 material is found to be stable, with minor changes in surface or bulk characteristics detected, even after 12 months of storage under ambient air conditions. The low surface reactivity to air also accounts for the minor changes to the electrochemical performance of the air-exposed LiNi0.5Mn1.5O4, compared to the pristine material. This study provides guidance for the appropriate storage, handling and processing of this high-performance cathode material.