The use of Pd catalysts on carbon-based structured materials for the catalytic hydrogenation of bromates in different types of water

[EN] The aim of this work is to study the activity of new Pd catalysts, supported on two different nano structured carbon materials, for bromate catalytic hydrogenation. The influence of the support has been studied, obtaining the best results with a palladium catalyst supported on carbon nanofibers (CNF) grown in sintered metal fibers (SMF). The results have shown the importance of the catalyst support in order to minimize the mass-transfer limitations ensuring an efficient catalyst use. In this way the most active catalysts are those with a mesoporous structure containing high dispersed Pd nanoparticles. The activity of this catalyst for bromate reduction has been tested in different types of water, namely, distilled water, natural water and industrial wastewater. It has been shown that the catalyst activity depends on the water matrix and bromate reduction rate depends on the hydrogen partial pressure. The potential use of the catalyst has been studied in a continuous reactor. It has been observed that the catalyst is active without any important deactivation at least during 100 h of reaction, but is necessary to avoid salt precipitation and plugging problems.The authors thank the European Union (European Community's Seventh Framework Programme FP7/2007-2013 under grant agreement no. 226347 Project) for financial support. A.E. Palomares also acknowledges the support from the Spanish Government through the project MAT2012-38567-C02-01.Palomares Gimeno, AE.; Franch Martí, C.; Yuranova, T.; Kiwi-Minsker, L.; Garcia Bordeje, JE.; Derrouiche, S. (2014). The use of Pd catalysts on carbon-based structured materials for the catalytic hydrogenation of bromates in different types of water. Applied Catalysis B: Environmental. 146:186-191. https://doi.org/10.1016/j.apcatb.2013.02.056S18619114

Evaluation of the silver species nature in Ag-ITQ2 zeolites by the CO oxidation reaction

The authors thank the Spanish Ministry of Economy and Competitiveness through RTI2018-101784-B-I00 (MINECO/FEDER) and SEV-2016-0683 projects for the financial support. We gratefully acknowledge ALBA synchrotron for allocating beamtime (proposal 2015091414) and the CLAESS beamline staff for their help and technical support during our experiment. CG and NB thank the TUW Innovative Project GIP165CDGC. CG, SP, VT, NB and GR are thankful for financial support from the Austrian Science Fund (FWF) through projects DK+ Solids4Fun (W1243) and ComCat (I 1041-N28). I. Lopez Hernandez is grateful to Generalitat Valenciana and European Social Fund for the pre doctoral grant ACIF2017.López-Hernández, I.; García Yago, CI.; Truttmann, V.; Pollit, S.; Barrabés, N.; Rupprechter, G.; Rey Garcia, F.... (2020). Evaluation of the silver species nature in Ag-ITQ2 zeolites by the CO oxidation reaction. 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Maslinic Acid, a Natural Triterpene, Induces a Death Receptor-Mediated Apoptotic Mechanism in Caco-2 p53-Deficient Colon Adenocarcinoma Cells

Maslinic acid (MA) is a natural triterpene present in high concentrations in the waxy skin of olives. We have previously reported that MA induces apoptotic cell death via the mitochondrial apoptotic pathway in HT29 colon cancer cells. Here, we show that MA induces apoptosis in Caco-2 colon cancer cells via the extrinsic apoptotic pathway in a dose-dependent manner. MA triggered a series of effects associated with apoptosis, including the cleavage of caspases -8 and -3, and increased the levels of t-Bid within a few hours of its addition to the culture medium. MA had no effect on the expression of the Bax protein, release of cytochrome-c or on the mitochondrial membrane potential. This suggests that MA triggered the extrinsic apoptotic pathway in this cell type, as opposed to the intrinsic pathway found in the HT29 colon-cancer cell line. Our results suggest that the apoptotic mechanism induced in Caco-2 may be different from that found in HT29 colon-cancer cells, and that in Caco-2 cells MA seems to work independently of p53. Natural antitumoral agents capable of activating both the extrinsic and intrinsic apoptotic pathways could be of great use in treating colon-cancer of whatever origin.This study was supported by grants Group BIO 157 from the Technology and Innovation Council of the Andalucian regional government and AGL2006-12210-C03-02/ALI, SAF2005-01627, ISCIII-RTICC (RD06/0020/0046) from the Spanish government and European Union FEDER funds

Characterization of the proton pulsed beam at CMAM

In this paper, the technicalities performed to obtain a pulsed beam at the CMAM facility will be explained. The pulsed beam has been characterized with an 8 MeV proton beam, using an existing equipment at CMAM: two pairs of electrostatic plates (RASTER) that deflect the beam, commonly used for homogeneous irradiation of large areas. A pulsed beam is used in many areas such as nuclear physics, material science and, in particular, for proton-therapy medical studies. Rectangular and pyramidal functions have been used to generate different pulses and characterize the response of the RASTER. The results point out that the pulses obtained are suitable for preclinical proton-therapy studies in the FLASH regime, which consists on fractionating the dose in time with short and intense pulses. The set-up for the characterization has been a function generator and a Si-PM outside the chamber

Superconducting Sr2RuO4 Thin Films without Out-of-Phase Boundaries by Higher-Order Ruddlesden-Popper Intergrowth

Ruddlesden-Popper (RP) phases (An+1B n O3n+1, n = 1, 2,···) have attracted intensive research with diverse functionalities for device applications. However, the realization of a high-quality RP-phase film is hindered by the formation of out-of-phase boundaries (OPBs) that occur at terrace edges, originating from lattice mismatch in the c-axis direction with the A'B'O3 (n = ∞) substrate. Here, using strontium ruthenate RP-phase Sr2RuO4 (n = 1) as a model system, an experimental approach for suppressing OPBs was developed. By tuning the growth parameters, the Sr3Ru2O7 (n = 2) phase was formed in a controlled manner near the film-substrate interface. This higher-order RP-phase then blocked the subsequent formation of OPBs, resulting in nearly defect-free Sr2RuO4 layer at the upper region of the film. Consequently, the Sr2RuO4 thin films exhibited superconductivity up to 1.15 K, which is the highest among Sr2RuO4 films grown by pulsed laser deposition. This work paves the way for synthesizing pristine RP-phase heterostructures and exploring their unique physical properties

Challenges of viticulture adaptation to global change: tackling the issue from the roots

Viticulture is facing emerging challenges not only because of the effect of climate change on yield and composition of grapes, but also of a social demand for environmental-friendly agricultural management. Adaptation to these challenges is essential to guarantee the sustainability of viticulture. The aim of this review is to present adaptation possibilities from the soil-hidden, and often disregarded, part of the grapevine, the roots. The complexity of soil-root interactions makes necessary a comprehensive approach taking into account physiology, pathology and genetics, in order to outline strategies to improve viticulture adaptation to current and future threats. Rootstocks are the link between soil and scion in grafted crops, and they have played an essential role in viticulture since the introduction of phylloxera into Europe at the end of the 19th century. This review outlines current and future challenges that are threatening the sustainability of the wine sector and the relevant role that rootstocks can play to face these threats. We describe how rootstocks along with soil management can be exploited as an essential tool to deal with the effects of climate change and of emerging soil-borne pests and pathogens. Moreover, we discuss the possibilities and limitations of diverse genetic strategies for rootstock breeding.This work is framed in the networking activities of RedVitis (AGL2015-70931-REDT) and RedVitis 2.0 (AGL2017-90759-REDT), funded by the State Research Agency (AEI) of the Spanish Ministry of Science and Innovation. Ms Diana Marin is beneficiary of postgraduate scholarship funded by Universidad Publica de Navarra (FPI-UPNA-2016). Dr Juan Emilio Palomares-Rius acknowledges the State Research Agency (AEI) of the Spanish Ministry of Science and Innovation for the 'Ramon y Cajal' Fellowship RYC-2017-22228 and Dr David Gramaje acknowledges Spanish Ministry of Economy and Competitiveness for the 'Ramon y Cajal' Fellowship RYC-2017-23098