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The electrons that nature uses to reduce CO2 during photosynthesis come from water oxidation at the oxygen-evolving complex of photosystem II. Molecular catalysts have served as models to understand its mechanism, in particular the O-O bond-forming reaction, which is still not fully understood. Here we report a Ru(IV) side-on peroxo complex that serves as a 'missing link' for the species that form after the rate-determining O-O bond-forming step. The Ru(IV) side-on peroxo complex (eta(2)-1(IV)-OO) is generated from the isolated Ru(IV) oxo complex (1(IV)=O) in the presence of an excess of oxidant. The oxidation (IV) and spin state (singlet) of eta(2)-1(IV)-OO were determined by a combination of experimental and theoretical studies. O-18- and H-2-labelling studies evidence the direct evolution of O-2 through the nucleophilic attack of a H2O molecule on the highly electrophilic metal-oxo species via the formation of eta(2)-1(IV)-OO. These studies demonstrate water nucleophilic attack as a viable mechanism for O-O bond formation, as previously proposed based on indirect evidence.

The development of CO2 electroreduction (CO2RR) catalysts based on covalent organic frameworks (COFs) is an emerging strategy to produce synthetic fuels. However, our understanding on catalytic mechanisms and structure-activity relationships for COFs is still limited but essential to the rational design of these catalysts. Herein, we report a newly devised CO2 reduction catalyst by loading single-atom centers, {fac-Mn(CO)(3)S}, (S = Br, CH3CN, H2O), within a bipyridylbased COF (COFbpyMn). COFbpyMn shows a low CO2RR onset potential (eta = 190 mV) and high current densities (>12 mA.cm(-2), at 550 mV overpotential) in water. TOFCO and TONCO values are as high as 1100 h-1 and 5800 (after 16 h), respectively, which are more than 10-fold higher than those obtained for the equivalent manganese-based molecular catalyst. Furthermore, we accessed key catalytic intermediates within a COF matrix by combining experimental and computational (DFT) techniques. The COF imposes mechanical constraints on the {fac-Mn(CO)(3)S} centers, offering a strategy to avoid forming the detrimental dimeric Mn-0-Mn-0, which is a resting state typically observed for the homologous molecular complex. The absence of dimeric species correlates to the catalytic enhancement. These findings can guide the rational development of isolated single-atom sites and the improvement of the catalytic performance of reticular materials.

The photocatalytic and electrocatalytic conversion of CO

This article aims to evaluate substance abuse in a sample of personnel who works in the Military Central Hospital through the digital application of two clini-metrical scales, the Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) and the Alcohol Use Disorder Identification Test (AUDIT).

The electrochemical reduction of carbon dioxide (CO

The electrochemical behavior of fac-[Mn(pdbpy)(CO)3 Br] (pdbpy=4-phenyl-6-(phenyl-2,6-diol)-2,2'-bipyridine) (1) in acetonitrile under Ar, and its catalytic performances for CO2 reduction with added water, 2,2,2-trifluoroethanol (TFE), and phenol are discussed in detail. Preparative-scale electrolysis experiments, carried out at -1.5 V versus the standard calomel electrode (SCE) in CO2 -saturated acetonitrile, reveal that the process selectivity is extremely sensitive to the acid strength, producing CO and formate in different faradaic yields. A detailed spectroelectrochemical (IR and UV/Vis) study under Ar and CO2 atmospheres shows that 1 undergoes fast solvolysis; however, dimer formation in acetonitrile is suppressed, resulting in an atypical reduction mechanism in comparison with other reported MnI catalysts. Spectroscopic evidence of Mn hydride formation supports the existence of different electrocatalytic CO2 reduction pathways. Furthermore, a comparative investigation performed on the new fac-[Mn(ptbpy)(CO)3 Br] (ptbpy=4-phenyl-6-(phenyl-3,4,5-triol)-2,2'-bipyridine) catalyst (2), bearing a bipyridyl derivative with OH groups in different positions to those in 1, provides complementary information about the role that the local proton source plays during the electrochemical reduction of CO2 .

The electrochemical reduction of carbon dioxide (CO2) powered by renewable energy is an attractive sustainable approach to mitigate CO(2)emissions and to produce fuels or value-added chemicals. In order to tackle the challenges related to selectivity, activity, overpotential and durability, transition metal-based catalysts have been widely investigated in the last decades. In an effort to bridge the gap between the fields of homogeneous and heterogeneous catalysis, this review aims to survey the main strategies explored for the rational design of a wide variety of different metal catalysts, ranging from molecular systems to single-atom and nanostructured catalysts. Transition metal complexes containing heme and non-heme ligands have been selected to discuss the recent advances in the understanding of the structure-function relationship in molecular homogeneous catalysis as well as to summarize the main approaches proposed for the heterogenization or confinement of molecular catalysts on conductive surfaces. The main strategies to minimize catalyst cost are also presented, leading to atomically dispersed molecular-like M-N(x)moieties embedded on 2D conducting materials. The superior performances of single-atom catalysts (SACs) and the structural similarity with their molecular analogs, suggest that transition metal catalysts containing well-defined sites may be intrinsically more active and selective towards CO(2)conversion than the bulk heterogeneous materials. Finally, design approaches for metal nanoparticles (NPs) based on size, shape, and support tuning are summarized and compared to novel strategies based on the interaction with surface-bonded organic molecules. The studies herein presented show that the basic principles in molecular catalysis and organometallic chemistry can be effectively used to design new efficient and selective heterogeneous catalysts for CO(2)reduction.

A mechanistic understanding of electro- and photocatalytic CO

Automation of flexible surgical instruments requires the development of robotic technologies capable of small-scale power transmission. Magnetic actuation has successfully been used for that purpose. Nevertheless, current systems for magnetic actuation suffer from small workspaces or poor bandwidth of magnetic field control. In this work, we design, develop, and test a novel magnetic actuation system called Advanced Robotics for Magnetic Manipulation (ARMM). The ARMM system employs a 6 DoF mobile electromagnetic coil capable of generating prescribed magnetic fields and gradients. The mobile coil approach allows for easy scaling of the actuation workspace, which depends on the range of robotic arm, and in our case spans up to 1.3 m. Due to limited end-effector payload of the robotic arm used in the ARMM system, the mobile coil has been designed using an optimization routine. For a given mass and heat dissipation constraints, this routine provides the coil geometry that maximizes the average magnetic field generated in the target region. Since the Vacoflux core of the fabricated coil saturates within operational conditions, we propose an actuation strategy employing an online-updated iterative map technique. Using this map, the ARMM system allows for precise generation of prescribed magnetic fields and gradients at the point of interest, while taking into account the effects of the non-linearities due to core saturation. The strategy is validated experimentally, showing the average error of 2.34% for magnetic field and 7.20% for the magnetic field gradient.

The chemical inertness of abundant and commercially available alkyl chlorides precludes their widespread use as reactants in chemical transformations. Presented in this work is a metallaphotoredox methodology to achieve the catalytic intramolecular reductive cyclization of unactivated alkyl chlorides with tethered alkenes. The cleavage of strong C(sp3)@Cl bonds is mediated by a highly nucleophilic lowvalent cobalt or nickel intermediate generated by visible-light photoredox reduction employing a copper photosensitizer. The high basicity and multidentate nature of the ligands are key to obtaining efficient metal catalysts for the functionalization of unactivated alkyl chlorides.

Electrocatalytic CO2 reduction has emerged as a promising strategy to effectively produce fuels and chemicals sustainably. In this regard, the study of electrochemical catalytic reduction of CO2 with metal complexes is a powerful tool for both the development of catalysts that operated under desired conditions (low overpotentials, high catalytic rates and selectivity, and extended durability) and the understanding of basic principles in catalysis. To illustrate the state-of-the-art, this revision presents a selection of the most recent and remarkable findings reported in terms of key strategies to improve reaction rates, selectivity and mechanism understanding for the leading families of homogeneous catalysts.

Ponencia presentada en: VI Simposio Nacional de Predicción, celebrado en los servicios centrales de AEMET, en Madrid, del 17 al 19 de septiembre de 2018. La iniciativa MedCOF forma parte de la red de los Foros Climáticos Regionales de Perspectivas del Clima (RCOF, por sus siglas en inglés) y su ámbito de actuación se centra en la región mediterránea. Los RCOF están reconocidos como uno de los principales elementos del Marco Mundial de Servicios Climáticos (GFCS, por sus siglas en inglés) liderado por la OMM. MedCOF se lanzó en junio de 2013 y desde entonces ha venido elaborando dos predicciones estacionales consensuadas anuales (verano e invierno) para todo el Mediterráneo. MedCOF incluye a 34 países con sus respectivos servicios meteorológicos nacionales, así como centros de investigación activos en el campo de la predicción estacional. El objetivo general de MedCOF es reforzar la colaboración entre los países mediterráneos y, en particular, entre las Asociaciones Regionales I y VI de la OMM, para desarrollar capacidades del Sistema de Información de Servicios Climáticos en el marco del GFCS. En particular, MedCOF tiene como prioridades: i) la explotación óptima de todos los recursos de información sobre predicción estacional; ii) la necesidad de proporcionar una respuesta coordinada y acordada de todos los servicios meteorológicos de la región ante la creciente demanda de información a escala estacional; iii) organización de actividades de formación y iv) aumentar la cooperación en tareas que requieren recursos que en muchos casos exceden las capacidades de los servicios meteorológicos individuales. En esta comunicación se describirá en detalle el funcionamiento y desarrollo pasado de esta iniciativa y su posible evolución en el marco de la reformulación que se pretende dar a los RCOF desde la OMM.

We report here the first purely organometallic fac‐[MnI(CO)3(bis‐MeNHC)Br] complex with unprecedented activity for the selective electrocatalytic reduction of CO2 to CO, exceeding 100 turnovers with excellent faradaic yields (η CO≈95 %) in anhydrous CH3CN. Under the same conditions, a maximum turnover frequency (TOFmax) of 2100 s−1 was measured by cyclic voltammetry, which clearly exceeds the values reported for other manganese‐based catalysts. Moreover, the addition of water leads to the highest TOFmax value (ca. 320 000 s−1) ever reported for a manganese‐based catalyst. A MnI tetracarbonyl intermediate was detected under catalytic conditions for the first time.

A new family of cobalt complexes with the general formula [CoII(OTf)2(Y,XPyMetacn)] (1R,Y,XPyMetacn ¼ 1-[(4-X-3,5-Y-2-pyridyl)methyl]-4,7-dimethyl-1,4,7-triazacyclononane, (X ¼ CN (1CN), CO2Et (1CO2Et), Cl (1Cl), H(1H), NMe2 (1NMe2)) where (Y ¼ H, and X ¼ OMe when Y ¼ Me (1DMM)) is reported. We found that the electronic tuning of the Y,XPyMetacn ligand not only has an impact on the electronic and structural properties of the metal center, but also allows for a systematic water-reduction-catalytic control. In particular, the increase of the electron-withdrawing character of the pyridine moiety promotes a 20-fold enhancement of the catalytic outcome. By UV-Vis spectroscopy, luminescence quenching studies and Transient Absorption Spectroscopy (TAS), we have studied the direct reaction of the photogenerated [IrIII(ppy)2(bpyc )] (PSIr) species to form the elusive CoI intermediates. In particular, our attention is focused on the effect of the ligand architecture in this elemental step of the catalytic mechanism. Finally, kinetic isotopic experiments together with DFT calculations provide complementary information about the rate-determining step of the catalytic cycle We would like to thank the European Commission for the ERCCG-2014-648304 (J.Ll.-F) project. The financial support from ICIQ Foundation and CELLEX Foundation through the CELLEXICIQ high throughput experimentation platform and the Starting Career Program is gratefully acknowledged. We also thank CERCA Programme (Generalitat de Catalunya); The MINECO is acknowledged for a FPU fellowship to A.C (AP2012- 6436) and ICIQ-IPMP program (F.F.) and Severo Ochoa Excellence Accreditation 2014–2018 (SEV-2013-0319). J.M.L. is grateful for financial support from the Spanish MINECO CTQ2014-52525-P and the Catalan DIUE 2014SGR931. J.P-P. gratefully acknowledge CTQ2014-60174-P (partially co-financed with FEDER funds), Maria de Maeztu (MDM-2015-0538), RyC contract to MGB) and Fundación Ramón Areces for financial support

The electrochemical behavior of fac-[Mn(pdbpy)(CO)

S-CimWaRe es el resultado de un grupo de trabajo multidisciplinar impulsado por AEMET y la Direccion General del Agua creado con el objetivo de desarrollar un servicio climatico experimental para el apoyo a la gestion de los embalses en Espana. Este proyecto forma parte de las actividades de implementacion en Espana del Marco Mundial de Servicios Climaticos y se desarrolla como un caso de estudio dentro del proyecto europeo FP7 EUPORIAS que trabaja en el desarrollo de sistemas de prevision de impactos a escala estacional y decadal para el apoyo a la toma de decisiones dependientes del clima. En S-ClimWaRe se han seleccionado 4 embalses de las cuencas del Duero, Tajo, Ebro y Guadalquivir en los que se esta probando la utilizacion de las predicciones climaticas estacionales (Pouget et al., 2015). El proyecto combina datos de observacion hidrologicos y meteorologicos, el sistema estadistico de prediccion estacional de aportaciones que se describe en este documento y un modelo de prevision de riesgos de los embalses, SIMRISK, que fue desarrollado por la Universidad Politecnica de Valencia (Andreu et al., 1996). Asi mismo, el proyecto contempla la formacion en los temas que se van desarrollando, actividades de divulgacion y un activo foro de encuentro entre los agentes implicados. Este documento es un extracto del documento de referencia que con el titulo “Sistema Estadistico de Prediccion Estacional para la Gestion de los Embalses en Espana” sera pub

The effects of the highly fluorescent 4-piperidinyl-1,8-naphthalimide (PNI) chromophore on the CO2 reduction catalytic properties of rhenium-based catalysts are investigated herein. In particular, the electro- and photocatalytic CO2 reduction features of [Re(CO)3(bpy)Cl] (bpy = 2,2′-bipyridine) are compared with the activity of [Re(CO)3(phen–PNI)Cl] (phen = 1,10-phenanthroline), which is known for its long excited-state lifetime. Moreover, another Re complex, namely [Re(CO)3(bpy–Ph–PNI)Cl], has been synthesized and tested as an electro- and photocatalyst. The catalytic properties of the selected compounds were studied by means of electrochemical (cyclic voltammetry and controlled-potential electrolysis) and photophysical measurements together with DFT calculations. [Re(CO)3(bpy–Ph–PNI)Cl] showed good electrocatalytic efficiency toward selective CO2 reduction to CO, as well as reduced electrocatalytic overpotential.

Tetracarbonyl complexes of low-valent Group VI transition metals (Mo and W), containing diimine bidentate ligands, namely W(CO)4(4,6-diphenyl-2,2′-bipyridine) (1), W(CO)4(6-(2,6-dimethoxyphenyl)-4-phenyl-2,2′-bipyridine) (2), Mo(CO)4(2,2′-dipyridylamine) (3), and W(CO)4(2,2′-dipyridylamine) (4), were synthesized and tested as homogeneous catalysts for the electrochemical reduction of CO2 in nonaqueous media. Cyclic voltammetry performed under a CO2 atmosphere, revealed that these complexes have significant catalytic activity in acetonitrile, and gas chromatographic measurements together with exhaustive electrolysis showed that CO is the major reduction product. Mechanistic insights were obtained by IR-spectroelectrochemical measurements. The substantially different electrocatalytic performances obtained for the two classes of catalysts are compared and discussed.