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We present the summary of several years of research about the inhibitor effect of NO2- on the corrosion of reinforcements. We have studied their inhibitor effect using galvanostatic and potentiodynamic polarization curves and we have measured the corrosion rates using the Polarization Resistance method (linear polarization). We have verified by this last technique, Rp, that the NO2- in concrete, if they are used in sufficient proportion, are a complete inhibitor when the Cl are added during the mixing (e.g. mixing whith sea water, CaCl2 as an accelerator in inbitor). Inssufficient amounts of NO2- have never provoked more corrosion in our experiments in concrete. The presence of NO2- always have produced a beneficial effect. The NO2- are also beneficial in carbonated concrete, suppressing or, at least, reducing the attacked area and the corrosion rate of the reinforcements.

AbstractMicrobial carbon (C) use efficiency (CUE) delineates the proportion of organic C used by microorganisms for anabolism and ultimately influences the amount of C sequestered in soils. However, the key factors controlling CUE remain enigmatic, leading to considerable uncertainty in understanding soil C retention and predicting its responses to global change factors. Here, we investigate the global patterns of CUE estimate by stoichiometric modeling in surface soils of natural ecosystems, and examine its associations with temperature, precipitation, plant‐derived C and soil nutrient availability. We found that CUE is determined by the most limiting resource among these four basic environmental resources within specific climate zones (i.e., tropical, temperate, arid, and cold zones). Higher CUE is common in arid and cold zones and corresponds to limitations in temperature, water, and plant‐derived C input, while lower CUE is observed in tropical and temperate zones with widespread limitation of nutrients (e.g., nitrogen or phosphorus) in soil. The contrasting resource limitations among climate zones led to an apparent increase in CUE with increasing latitude. The resource‐specific dependence of CUE implies that soils in high latitudes with arid and cold environments may retain less organic C in the future, as warming and increased precipitation can reduce CUE. In contrast, oligotrophic soils in low latitudes may increase organic C retention, as CUE could be increased with concurrent anthropogenic nutrient inputs. The findings underscore the importance of resource limitations for CUE and suggest asymmetric responses of organic C retention in soils across latitudes to global change factors.

Thermodynamic cycles requiring high operating temperatures (≥750 °C up to 1200 °C) are currently being explored to improve the sun-to-electricity conversion efficiency of Concentrating Solar Power (CSP) plants. This is calling for the design of new efficient high-temperature (≥750 °C) Thermochemical Energy Storage (TCES) systems, which are fundamental for supplying power on demand during off-sun periods. Recently, Fe-doped CaMnO3 oxides have been proposed as TCES candidate materials, and the determination of their thermodynamics properties via thermogravimetric (TG) analysis allowed evaluation of their heat storage capacity at a very small scale (mg scale). A 10 % Fe-doped CaMnO3 composition (CaMn0.9Fe0.1O3-δ – CMF91) emerged as optimum candidate material for TCES application due to its large heat storage capacity complemented by enhanced thermal stability over multiple oxidation/reduction cycles. To advance in the thermal characterization of these materials at a multigram scale, here we carried out bench-scale reactor tests using CMF91 under conditions considered representative of future CSP plants. The redox-active material has been extruded in the form of porous pellets through a simple production method that required the use of carboxymethylcellulose as a removable binder and water. With the bench-scale reactor tests, the CMF91 pellets showed fully reversible reduction-oxidation in cycles between 500 and 1100 °C under relevant operating pO2 conditions without any deterioration of the pellet's structural integrity. Remarkably, the material exhibited the same δ(T, pO2) profile at this significantly larger scale (~40 g) than the one derived from thermodynamics. Nevertheless, slight differences in oxygen release/uptake profiles between cooling and heating branches can be tracked down to an excess heat generation in the perovskite bed not efficiently extracted by the carrier gas. These results demonstrate that CMF91 oxide is ideally suited for thermal energy storage applications with a large total (thermochemical and sensible) heat storage capacity (~ 916 kJ/kgABO3 or ~ 400 kWh/m3) and good scalability. © 2022 This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska- Curie grant agreement N◦ 74616. Support of the ACES2030-CM from “Comunidad de Madrid” and European Structural Funds to (P2018/EMT-4319), and the Spanish “Ministerio de Economía y Competitividad” through Research Challenges project ARROPAR-CEX (ENE2015-71254-C3-1-R) are also fully acknowledged. M. S´anchez is grateful to Spanish “Ministerio de Economía y Competitividad” by funding through internship FPI (BES-2016-077031). It is greatly acknowledged the Technical Research Support Unit of the Institute of Catalysis and Petroleum Chemistry (ICP-CSIC). The authors fully appreciate the advice provided by Prof. Pedro Avila and Dr. Raquel Portela from the SpeICat group of ICP-CSIC, about the procedure for pellets preparation. Supporting Information Peer reviewed

Recent advances in the satellite retrieval of solar-induced chlorophyll fluorescence (SIF) provide new opportunities for understanding the phenological responses of ecosystems to global climate change. Because of the strong link between SIF and plant gross photosynthesis, phenological events derived from SIF represent the seasonal variation of ecosystem functioning (photosynthetic phenology) and differ from phenologies derived from traditional vegetation indices. We provide an overview of recent advances in remotely sensed photosynthetic phenologies, with a focus on their driving factors, their impact on the global carbon cycle, and their relationships with vegetation index-derived land surface phenology metrics. We also discuss future research directions on how to better use various phenological metrics to understand the responses of plants to global change.

Abstract Hybrid TiO2/SiO2 thin films deposited by material printing technique on flexible substrates were prepared, characterized and tested for solar photocatalytic disinfection. Effect of surface hydrophilicity/hydrophobicity of printed coatings on photocatalytic disinfection was studied by means of (i) drinking water contaminated with natural consortia of fecal bacteria (gram-negative: Escherichia coli and total coliforms; gram-positive: Enterococci), and (ii) seawater containing pathogenic gram-negative bacteria (Vibrio owensii, Vibrio alfacsensis and Vibrio harveyi). Inactivation of gram-negative bacteria in drinking water with fecal contamination by solar photocatalysis was slightly more efficient than solar disinfection, while for gram-positive bacteria similar efficiency was observed. These results, in combination with observed release of titanium from coatings (detected by means of inductively coupled plasma atomic emission spectrometer), indicate that TiO2/SiO2 needs further improvements for solar photocatalytic disinfection of drinking water. Efficiency of seawater disinfection towards gram-negative Vibrio spp. (Vibrio owensii, Vibrio alfacsensis and Vibrio harveyi) was significantly enhanced when TiO2/SiO2 coatings were used under natural solar light. Moreover, hydrophobic thin films led to faster Vibrio spp. inactivation as compared to hydrophilic ones, which was attributed to higher bacteria adhesion on hydrophobic coatings. However, decrease of photocatalytic activity of hydrophobic TiO2/SiO2 coatings was observed after ten experimental cycles mainly due to deposition of salts on the surface of photocatalyst. Generally, results of this study suggest that autochthonous bacteria such as Vibrio spp. in seawater are significantly more resistant to solar disinfection in comparison with not autochthonous bacteria such as Escherichia coli, total coliforms and Enterococci in contaminated drinking water.

Abstract The dynamics of isolated-photon plus two-jet production in pp collisions at a centre-of-mass energy of 13 TeV are studied with the ATLAS detector at the LHC using a dataset corresponding to an integrated luminosity of 36.1 fb−1. Cross sections are measured as functions of a variety of observables, including angular correlations and invariant masses of the objects in the final state, γ + jet + jet. Measurements are also performed in phase-space regions enriched in each of the two underlying physical mechanisms, namely direct and fragmentation processes. The measurements cover the range of photon (jet) transverse momenta from 150 GeV (100 GeV) to 2 TeV. The tree-level plus parton-shower predictions from Sherpa and Pythia as well as the next-to-leading-order QCD predictions from Sherpa are compared with the measurements. The next-to-leading-order QCD predictions describe the data adequately in shape and normalisation except for regions of phase space such as those with high values of the invariant mass or rapidity separation of the two jets, where the predictions overestimate the data.