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Funding for this work was provided by King Abdullah University of Science and Technology (KAUST). The authors wish to thank and acknowledge to Dr. Serhii Vasylevskyi from KAUST-Core labs for his support during the Raman spectroscopy measurements, Dr. Natalia Morlanes for her assistance for the flow-reactor configuration, and Sandra Ramirez for the art work.

The combination of well-defined molecular cavities and chemical functionality makes crystalline porous solids attractive for a great number of technological applications, from catalysis to gas separation. However, in contrast to other widely applied synthetic solids such as polymers, the lack of processability of crystalline extended solids hampers their application. In this work, we demonstrate that metal–organic frameworks, a type of highly crystalline porous solid, can be made solution processable via outer surface functionalization using N-heterocyclic carbene ligands. Selective outer surface functionalization of relatively large nanoparticles (250 nm) of the well-known zeolitic imidazolate framework ZIF-67 allows for the stabilization of processable dispersions exhibiting permanent porosity. The resulting type III porous liquids can either be directly deployed as liquid adsorbents or be co-processed with state-of-the-art polymers to yield highly loaded mixed matrix membranes with excellent mechanical properties and an outstanding performance in the challenging separation of propylene from propane. We anticipate that this approach can be extended to other metal–organic frameworks and other applications. Solution processability is required for many industrial processes, but metal–organic frameworks are in general not dispersible, hindering their application. Here, a surface modification is reported that allows porous liquid formation and so synthesis of highly loaded and mechanically robust mixed matrix membranes.

Purpose This paper aims to describe the influence of maleinized linseed oil (MLO), when used as a lubricant, on the thermal and rheological properties of PLA/MWCNTs (polylactic acid/multi-walled carbon nanotubes) and PLA/HNT (halloysite nanotubes) nanocomposites, as a reference for application in 3D printing processes. Design/methodology/approach Nanocomposites were obtained by melting in a twin-screw extruder, mixing PLA with MWCNTs and HNTs in different percentages of 0.5, 0.75 and 1 Wt.% for subsequent mixing by the same process with 5 phr MLO, for application in additive manufacturing, as analyzed by means of differential scanning calorimetry (DSC), capillary rheometry, melt flow rate (MFL) and field emission scanning electron microscopy (FESEM). Findings The results obtained for thermal characterization by using DSC indicate the non-variation of glass transition temperature Tg = 62 ± 2°C and a melting temperature (Tm) around 170°C. Crystallization temperature dropped by approximately 12°C, which should be kept in mind during the transformation processes. The values obtained by capillary rheometry indicate that the material’s viscosity is reduced by the influence of the MLO plasticizer’s lubricant effect on the PLA’s molecular structure. The melt flow index values confirm a rise of approximately 46% in the flow index and back up the capillary rheometry results. The values obtained were as follows: PLA/0.5 Wt.% MWCNT/MLO 5 phr 54.07, PLA/0.75 Wt.% MWCNT/MLO 5 phr 53.46, PLA/1 Wt.% MWCNT/MLO 5 phr 51.84y PLA/0.5 Wt.% HNT/MLO 5 phr 61.8, PLA/0.75 Wt.% HNT/MLO 5 phr 68.3 and PLA/1 Wt.% HNT/MLO 5 phr 71.2 g/10 min. Apart from the nanocharge distribution, the information obtained from the FESEM shows the existence of a cluster, which could have been avoided by more energetic stirring during the nanocompound manufacturing process. Social implications This paper presents an analysis of the insertion of plasticizer in nanocomposites for the application in additive manufacturing processes in fusion deposition modelling (FDM) system. Originality/value This is a novel original research work.

El sector del transporte aéreo de Colombia se posiciona como el tercer país con mayor incremento de operaciones en las terminales aéreas de América Latina. Para alcanzar un crecimiento sostenible del sector, es necesario contar con metodologías de planificación basadas en estimaciones sobre la previsión de las cantidades de pasajeros. En este contexto de planificación operativa, este trabajo presenta varios modelos de pronóstico predictivo de largo plazo con base a las operaciones en vuelos nacionales e internacionales registradas por Aerocivil desde el año 2005. Se aplicó un enfoque de Modelado de Orden Diferenciado Estacional, Autoregresivo y de Medias Móviles (SARIMA). Se presenta una metodología secuencial para la selección de cinco modelos sobre un total de 256 calculados. El modelo (0,1,0)×(0,1,0)12 resultó ser el más apropiado con una estimación del RMSEA del 3.1%. Los modelos presentan altos rendimientos de estimación a pesar de los efectos causados por la última pandemia COVID-19.

Despite unprecedented progress in developing COVID-19 vaccines, global vaccination levels needed to reach herd immunity remain a distant target, while new variants keep emerging. Obtaining near universal vaccine uptake relies on understanding and addressing vaccine resistance. Simple questions about vaccine acceptance however ignore that the vaccines being offered vary across countries and even population subgroups, and differ in terms of efficacy and side effects. By using advanced discrete choice models estimated on stated choice data collected in 18 countries/territories across six continents, we show a substantial influence of vaccine characteristics. Uptake increases if more efficacious vaccines (95% vs 60%) are offered (mean across study areas=3.9%, range of 0.6%-8.1%) or if vaccines offer at least 12 months of protection (mean across study areas=2.4%, range of 0.2%-5.8%), while an increase in severe side effects (from 0.001% to 0.01%) leads to reduced uptake (mean=-1.3%, range of -0.2% to -3.9%). Additionally, a large share of individuals (mean=55.2%, range of 28%-75.8%) would delay vaccination by 3 months to obtain a more efficacious (95% vs 60%) vaccine, where this increases further if the low efficacy vaccine has a higher risk (0.01% instead of 0.001%) of severe side effects (mean=65.9%, range of 41.4%-86.5%). Our work highlights that careful consideration of which vaccines to offer can be beneficial. In support of this, we provide an interactive tool to predict uptake in a country as a function of the vaccines being deployed, and also depending on the levels of infectiousness and severity of circulating variants of COVID-19. We acknowledge financial support as follows: CN Chinese National Natural Science Foundation (72071017), the joint project of the National Natural Science Foundation of China and the Joint Programming Initiative Urban Europe (NSFC – JPI UE) (‘U- PASS’, 71961137005). CL Instituto Sistemas Complejos de Ingeniería (ISCI), through grant ANID PIA/BASAL AFB180003. ES FEDER/Ministry of Science, Innovation and Universities through grant PID2020-113650RB-I00; Basque Government through grant IT1359-19 (UPV/EHU Econometrics Research Group); BERC 2018–2021 programme; MICINN María de Maeztu excellence accreditation (MDM- 2017-0714). FR FR French National Research Agency Grants ANR-17-EURE-0020 and the Excellence Initiative of Aix-Marseille University - A*MIDEX. KR Creative-Pioneering Researchers Program through Seoul Na- tional University. NA Ndatara Surveys. NZ Waikato Management School. UK European Research Council through the consolidator grant 615596-DECISIONS; internal funding through the Choice Modelling Centre (CMC). We would also like to express our thanks to technical support from Aix-Marseille University, and thank Sofia Hern ́andez Benavides (CL), Simon Dec Pedersen (DK) and Robbie Maris (NZ) for help in data preparation and analysis.

We report the synthesis of a highly active and stable metal-organic framework derived Ni-based catalyst for the photothermal reduction of CO

Con este número el Área de Historia Medieval, a través de la Editorial de la Universidad de Jaén continúa la publicación de una serie de documentos que, por su extensión o especiales características, desbordan el marco de una revista como Arqueología y Territorio Medieval, pero se han considerado de interés para la comunidad investigadora. En este texto se presentan más de cuatrocientos fragmentos, seleccionados entre el material cerámico aparecido en una “cascotera” del barrio de los alfareros de la localidad de Úbeda. Pertenecen casi todos a piezas usuales en la vajilla de mesa y a distintas series ornamentales que responden a variadas influencias. Fechados entre mediados del siglo XVI y finales del siguiente, muestran trazos pintados en azul de cobalto sobre una cubierta blanca estannífera.

Con este número el Área de Historia Medieval, a través de la Editorial de la Universidad de Jaén continúa la publicación de una serie de documentos que, por su extensión o especiales características, desbordan el marco de una revista como Arqueología y Territorio Medieval, pero se han considerado de interés para la comunidad investigadora. En este texto se presentan más de cuatrocientos fragmentos, seleccionados entre el material cerámico aparecido en una “cascotera” del barrio de los alfareros de la localidad de Úbeda. Pertenecen casi todos a piezas usuales en la vajilla de mesa y a distintas series ornamentales que responden a variadas influencias. Fechados entre mediados del siglo XVI y finales del siguiente, muestran trazos pintados en azul de cobalto sobre una cubierta blanca estannífera.

Dry reforming of methane (DRM) involves the conversion of CO2 and CH4, the most important greenhouse gases, into syngas, a stoichiometric mixture of H2 and CO that can be further processed via Fischer–Tropsch chemistry into a wide variety of products. However, the devolvement of the coke resistant catalyst, especially at high pressures, is still hampering commercial applications. One of the relatively new approaches for the synthesis of metal nanoparticle based catalysts comprises the use of metal-organic frameworks (MOFs) as catalyst precursors. In this work we have explored MOF-74/CPO-27 MOFs as precursors for the synthesis of Ni, Co and bimetallic Ni-Co metal nanoparticles. Our results show that the bimetallic system produced through pyrolysis of a Ni-Co@CMOF-74 precursor displays the best activity at moderate pressures, with stable performance during at least 10 h at 700 °C, 5 bar and 33 L·h−1·g−1., Catalysts, 10 (5), ISSN:2073-4344

Pollution of water with heavy metals is a global environmental problem whose impact is especially severe in developing countries. Among water-purification methods, adsorption of heavy metals has proven to be simple, versatile, and cost-effective. However, there is still a need to develop adsorbents with a capacity to remove multiple metal pollutants from the same water sample. Herein, we report the complementary adsorption capacities of metal-organic frameworks (here, UiO-66 and UiO-66-(SH)) and inorganic nanoparticles (iNPs; here, cerium-oxide NPs) into composite materials. These adsorbents, which are spherical microbeads generated in one step by continuous-flow spray-drying, efficiently and simultaneously remove multiple heavy metals from water, including As(III and V), Cd(II), Cr(III and VI), Cu(II), Pb(II), and Hg(II). We further show that these microbeads can be used as a packing material in a prototype of a continuous-flow water treatment system, in which they retain their metal-removal capacities upon regeneration with a gentle acidic treatment. As proof-of-concept, we evaluated these adsorbents for purification of laboratory water samples prepared to independently recapitulate each of two strongly polluted rivers: the Bone (Indonesia) and Buringanga (Bangladesh) rivers. In both cases, our microbeads reduced the levels of all the metal contaminants to below the corresponding permissible limits established by the World Health Organization (WHO). Moreover, we demonstrated the capacity of these microbeads to lower levels of Cr(VI) in a water sample collected from the Sarno River (Italy). Finally, to create adsorbents that could be magnetically recovered following their use in water purification, we extended our spray-drying technique to simultaneously incorporate two types of iNPs (CeO and FeO) into UiO-66-(SH), obtaining CeO/FeO@UiO-66-(SH) microbeads that adsorb heavy metals and are magnetically responsive.

Metal–organic frameworks (MOFs) and covalent organic frameworks (COFs) are among the most attractive porous materials today. They exhibit outstanding porosity for countless applications such as gas storage, CO2 capture, gas separation, sensing, drug delivery, and catalysis. Moreover, researchers have recently begun to combine MOFs or COFs with other functional materials to obtain composites that boast the respective strengths, and mitigate the respective weaknesses, of each component, enabling enhanced performance in many of the aforementioned applications. Accordingly, development of methods for fabrication of MOFs, COFs, and related composites is important for facilitating adoption of these materials in industry. One promising synthetic technique is spray-drying, which is already well-integrated in manufacturing processes for diverse sectors. It enables rapid, continuous and scalable production of dry microspherical powders in a single step, leading to lower fabrication costs and shorter production times compared to traditional methods., This work was supported by the Spanish MINECO (Project RTI2018-095622-B-I00), the Catalan AGAUR (Project 2017 SGR 238), and the ERC, under the EU-FP7 (ERC-Co 615954). It was also funded by the CERCA Program/Generalitat de Catalunya. ICN2 is supported by the Severo Ochoa program from the Spanish MINECO (Grant No. SEV-2017-0706).

Covalent postsynthetic modification (PSM) of metal-organic frameworks (MOFs) has attracted much attention due to the possibility of tailoring the properties of these porous materials. Schiff-base condensation between an amine and an aldehyde is one of the most common reactions in the PSM of MOFs. Here, we report the use of the spray drying technique to perform this class of organic reactions, either between discrete organic molecules or on the pore surfaces of MOFs, in a very fast (1-2 s) and continuous way. Using spray drying, we show the PSM of two MOFs, the amine-terminated UiO-66-NH2 and the aldehyde-terminated ZIF-90, achieving conversion efficiencies up to 20 and 42%, respectively. Moreover, we demonstrate that it can also be used to postsynthetically cross-link the aldehyde groups of ZIF-90 using a diamine molecule with a conversion efficiency of 70%.

[Abstract] This work proposes a method based on image analysis and machine and statistical learning to model and estimate osteocyte growth (in type I collagen scaffolds for bone regeneration systems) and the collagen degradation degree due to cellular growth. To achieve these aims, the mass of collagen -subjected to the action of osteocyte growth and differentiation from stem cells- was measured on 3 days during each of 2 months, under conditions simulating a tissue in the human body. In addition, optical microscopy was applied to obtain information about cellular growth, cellular differentiation, and collagen degradation. Our first contribution consists of the application of a supervised classification random forest algorithm to image texture features (the structure tensor and entropy) for estimating the different regions of interest in an image obtained by optical microscopy: the extracellular matrix, collagen, and image background, and nuclei. Then, extracellular-matrix and collagen regions of interest were determined by the extraction of features related to the progression of the cellular growth and collagen degradation (e.g., mean area of objects and the mode of an intensity histogram). Finally, these critical features were statistically modeled depending on time via nonparametric and parametric linear and nonlinear models such as those based on logistic functions. Namely, the parametric logistic mixture models provided a way to identify and model the degradation due to biological activity by estimating the corresponding proportion of mass loss. The relation between osteocyte growth and differentiation from stem cells, on the one hand, and collagen degradation, on the other hand, was determined too and modeled through analysis of image objects’ circularity and area, in addition to collagen mass loss. This set of imaging techniques, machine learning procedures, and statistical tools allowed us to characterize and parameterize type I collagen biodegradation when collagen acts as a scaffold in bone regeneration tasks. Namely, the parametric logistic mixture models provided a way to identify and model the degradation due to biological activity and thus to estimate the corresponding proportion of mass loss. Moreover, the proposed methodology can help to estimate the degradation degree of scaffolds from the information obtained by optical microscopy. Ministerio de Asuntos Económicos y Transformación Digital; MTM2014-52876-R Ministerio de Asuntos Económicos y Transformación Digital; MTM2017-82724-R Xunta de Galicia; ED431C-2016-015 Xunta de Galicia; ED431G/01

Purpose This paper aims to propose using polylactic acid (PLA) as an alternative to nanocomposites in additive manufacturing processes in fusion deposition modelling (FDM) systems and describe its thermal and rheological conditions with multi-wall carbon nanotube (PLA/MWCNT) and halloysite nanotube (PLA/HNT) composites for possible applications in additive manufacturing processes. Design/methodology/approach PLA/MWCNTs and PLA/HNTs were obtained through fusion in a co-rotating twin-screw extruder. PLA was mixed with different percentages of MWCNTs and HNTs at concentrations of 0.5 Wt.%, 0.75 Wt.% and 1 Wt.%. Differential scanning calorimetry (DSC) and capillary rheometry were used to characterise these products, together with an analysis of the melt flow index (MFI). Findings The DSC data revealed that the nanocomposites had a glass transition temperature Tg = 65 ± 2°C and a melting temperature Tm = 169 ± 1°C. The crystallisation temperature of PLA/MWCNTs and PLA/HNTs was between 107 ± 2°C and 129°C, respectively. The viscosity data of PLA/MWCNTs and PLA/HNTs obtained by capillary rheometry indicated that the viscosity of the materials is the same as that of neat PLA. These results were confirmed by the higher fluidity index in the MFI analysis. Originality/value This paper presents an alternative for the applications of nanocomposites in additive manufacturing processes in FDM systems.

This is the peer reviewed version of the following article: Angewandte Chemie - International Edition 58.28 (2019): 9512-9516, which has been published in final form at https://doi.org/10.1002/ange.201904766. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions, Título del postprint: Enhanced Uptake in a MOF@COF Composite by Interfacial Pore Generation, Herein, we describe a new class of porous composites comprising metal–organic framework (MOF) crystals confined in single spherical matrices made of packed covalent-organic framework (COF) nanocrystals. These MOF@COF composites are synthesized through a two-step method of spray-drying and subsequent amorphous (imine-based polymer)-to-crystalline (imine-based COF) transformation. This transformation around the MOF crystals generates micro- and mesopores at the MOF/COF interface that provide far superior porosity compared to that of the constituent MOF and COF components added together. We report that water sorption in these new pores occurs within the same pressure window as in the COF pores. Our new MOF@COF composites, with their additional pores at the MOF/COF interface, should have implications for the development of new composites, This work was supported by the Spanish MINECO (projects PN MAT2016-77608-C3-1-P, FIS2017-86007-C3 and FPU2015/0248), the Catalan AGAUR (project 2014 SGR 80), the ERC, under EU-FP7 (ERC-Co 615954), and the CERCA Program/Generalitat de Catalunya. ICN2 is supported by the Severo Ochoa program from Spanish MINECO (Grant No. SEV-2017-0706). IFIMAC is supported by the Maria de Maeztu program (Grant No. MDM-2014-0377)

International audience; Anhydrous ethanol can be considered as one of the main alternatives to replace fossil fuels. However, the removal of water consumes the greatest fraction of the energy necessary for its production. Thus, the use of hydrous ethanol arises from a new fuel possibility and it has been successfully tested in a device such as a spark-ignition engine. For this reason, there is a need for the determination of fundamental properties of the ethanol-water-air mixtures. There are few experimental works in this area and the majority of them have been carried out in test conditions of pressure up to 1 atm. Thus, the main goal of the present work is to bridge this data gap. For this, the laminar burning velocities and Markstein length of ethanol-water–air flames at water content up to 30% v/v over a range of equivalence ratios from 0.7 to 1.4 up to 5 MPa and 380 and 450 K were experimentally determined. The method used was a constant volume bomb method with a central ignition. The results were compared to literature data and with predictions carried out with CHEMKIN-PRO using the three different kinetic mechanisms. In general, the results of the mechanisms lead to an overprediction in relation to the experimental results, though all of them predicted the burning velocity peaks at an equivalence ratio close to 1.1, which agreed with the experiments. The experiments conducted that increased water content of water fuel mixtures have a tendency to remain stable under a stretch influence. Also, it is possible to observe a linear relationship describing the influence of the diluent on the laminar burning velocity.

Metal-organic frameworks (MOFs) usually require meticulous removal of the solvent molecules to unlock their potential porosity. Herein, we report a novel one-step method for activating MOFs based on the photothermal effect induced by directly irradiating them with a UV-vis lamp. The localized light-to-heat conversion produced in the MOF crystals upon irradiation enables a very fast solvent removal, thereby significantly reducing the activation time to as low as 30 min and suppressing the need for time-consuming solvent-exchange procedures and vacuum conditions. This approach is successful for a broad range of MOFs, including HKUST-1, UiO-66-NH2, ZIF-67, CPO-27-M (M = Zn, Ni, and Mg), Fe-MIL-101-NH2, and IRMOF-3, all of which exhibit absorption bands in the light emission range. In addition, we anticipate that this photothermal activation can also be used to activate covalent organic frameworks (COFs)., This work was supported by the Spanish MINECO (projects PN MAT2015-65354-C2-1-R), the Catalan AGAUR (project 2014 SGR 80), the ERC under the EU FP7 (ERC-Co 615954), and European Union’s Horizon 2020 research and innovation programme under grant agreement No 685727. It was also funded by the CERCA Programme / Generalitat de Catalunya. ICN2 acknowledges the support of the Spanish MINECO through the Severo Ochoa Centers of Excellence Program, under Grant SEV2013-0295. J.E. acknowledges the MINECO for the FPI fellowship.

Here, we report the covalent post-synthetic modification (CPSM) of MOFs using the photothermal effect. Specifically, we subjected mixtures of a photothermally active MOF and another reagent to irradiation with a UV-Vis lamp. This caused the MOF to heat up, which in turn caused the other reagent to melt and subsequently react with the functional groups on the walls of the MOF pores. We have exploited this dual function of MOFs as both heater and host for CPSMs to achieve rapid formation of amides from the reaction of representative MOFs (UiO-66-NH2 or MIL-101-NH2-(Al)) with anhydrides under solvent-free conditions. In addition, this approach enables more complex CPSMs in MOFs such as the formation of amides in UiO-66-NH2 by using an aldehyde through a cascade reaction., This work was supported by the EU FP7 ERC-Co 615954, the Spanish MINECO (project PN MAT2015-65354-C2-1-R), and the Catalan AGAUR (project 2014 SGR 80). It was also funded by the CERCA Programme/Generalitat de Catalunya. ICN2 acknowledges the support of the Spanish MINECO through the Severo Ochoa Centers of Excellence Programme under Grant SEV-2013-0295. J. E. acknowledges the MINECO for the FPI fellowship.

[Abstract] The poly(DL-lactide-co-glycolide) (PDLGA) copolymers have been specifically designed and performed as biomaterials, taking into account their biodegradability and biocompatibility properties. One of the applications of statistical degradation models in material engineering is the estimation of the materials degradation level and reliability. In some reliability studies, as the present case, it is possible to measure physical degradation (mass loss, water absorbance, pH) depending on time. To this aim, we propose an expert system able to provide support in collagen degradation analysis through computer vision methods and statistical modelling techniques. On this base, the researchers can determine which statistical model describes in a better way the biomaterial behaviour. The expert system was trained and evaluated with a corpus of 63 images (2D photographs obtained by electron microscopy) of human mesenchymal stem cells (CMMh-3A6) cultivated in a laboratory experiment lasting 44 days. The collagen type-1 sponges were arranged in 3 groups of 21 samples (each image was obtained in intervals of 72 hours).

[Abstract] The Poly(DL-lactide-co-glycolide) copolymers (PDLGA) have designed and performed as biomaterials, taking into account their biodegradability and biocompatibility properties. These materials have a wide range of application in medicine such as orthopedic implants, general surgical implants (suture materials), osteosynthesis, bone cement, among many others. For these reasons, in this paper, we present an intelligent educational environment that can be used for both, researchers and students interested in the analysis of the biomaterial behavior under certain conditions. Our platform includes a Learning Objects (LOs) for MOODLE, and in the same way, implements several digital image processing techniques as well as a decision support module based on a random forest algorithm and statistical modeling. With the aim of determining the real feasibility of this proposal, we have presented the system to 34 Ecuadorian engineering students. After testing the platform, the students answered a survey aimed at determining their perception of the system. The results provide several guidelines to continue with the developing of the platform.

A polymeric natural fiber-reinforced composite is developed by extrusion and injection molding process. The shrinkage and warpage of high-density polyethylene reinforced with short natural fibers of Guadua angustifolia Kunth are analyzed by experimental measurements and computer simulations. Autodesk Moldflow® and Solid Works® are employed to simulate both volumetric shrinkage and warpage of injected parts at different configurations: 0 wt.%, 20 wt.%, 30 wt.% and 40 wt.% reinforcing on shrinkage and warpage behavior of polymer composite. Become evident the restrictive effect of reinforcing on the volumetric shrinkage and warpage of injected parts. The results indicate that volumetric shrinkage of natural composite is reduced up to 58% with fiber increasing, whereas the warpage shows a reduction form 79% to 86% with major fiber content. These results suggest that it is a highly beneficial use of natural fibers to improve the assembly properties of polymeric natural fiber-reinforced composites.

Facultad de Ingeniería Química. Maestría en Ciencias en Ingeniería Química In order to satisfy the demand for fuel, the oil deposits of light crudes have been overexploited in the world. The heavy crude deposits, consisting of large aliphatic chains and sulfur compounds, among these sulphide compounds, are outstanding. Dibenzothiophene and its derivatives alkyl [1-2]. The United States, China and the European Union in the European Union to reduce sulfur content in fuels below 10 ppm [1]; What has become a tool for research in catalysis, on the basis of series, requiring solid materials and resistant to high temperatures, pressure and poisoning. The present project will address the development of a catalytic system, through a three-dimensional catalyst such as CoMoW supported on graphene and ?-Alumina that will allow a hydrodesulfurization of dibenzothiophene. The approach of using a supported trimetallic catalyst lies in the formation of the three-dimensional phase, which is attributed to the high conversion in the HDS reaction [4]; the low surface properties and the high cost of these mass catalysts because of their high metal content; could improve with the use of a support, which would help to have a good dispersion and coordination of the deposited active phase [3]. The use of graphene as a support, due to its modifiable structure, which helps to improve the interaction of the support with the active phase, in addition to some systems, makes it easier for the metals to remain reduced, which is good for the HDS reaction. Para satisfacer la alta demanda de combustible, en el mundo se han sobreexplotado los yacimientos petroleros de crudos livianos, quedando remanente los yacimientos de crudo pesado, constituidos por grandes cadenas alifáticas y compuestos sulfurados, entre estos compuestos sulfurados, destaca el dibenzotiofeno y sus derivados de alquilo[1-2]. Estados Unidos, China y la Unión Europea poseen regulaciones ambientales, para reducir el contenido de azufre en combustibles por debajo de 10 ppm [1]; lo que se ha convertido en un reto para la investigación en catálisis, alcanzar estos estándares, requiriendo materiales sólidos y resistentes a condiciones de alta temperatura, presión y envenenamiento. El presente proyecto aborda el desarrollo de un sistema catalítico, a través de un catalizador trimetálico como el CoMoW soportados sobre grafeno y ?-Alumina el cual permita una eficaz hidrodesulfuración de dibenzotiofeno. El planteamiento de utilizar un catalizador trimetálico soportado, radica en la formación de la fase trimetálica, a la cual se le atribuye la alta conversión en la reacción de HDS [4]; las bajas propiedades superficiales y el elevado costo de estos catalizadores másicos, por su alto contenido de metal; podría mejorar con la utilización de un soporte, el cual ayudaría tener una buena dispersión y coordinación de la fase activa depositada [3]. El uso de grafeno como soporte, se debe a su estructura modificable, la cual ayudaría a mejorar la interacción del soporte con la fase activa, además en algunos sistemas, facilita que los metales permanezcan reducidos, lo que es ventajoso para la reacción HDS.

Here we report a method that combines the spray-drying technique with a dynamic covalent chemistry process to synthesize zero-dimensional, spherical and microscale superstructures made from the assembly of imine-based COF nanocrystals. This methodology also enables the integration of other functional materials into these superstructures forming COF-based composites., This work was supported by the Spanish MINECO (project PN MAT2015-65354-C2-1-R), the Catalan AGAUR (project 2014 SGR 80), and the ERC under the EU FP7 (ERC-Co 615954). It was also funded by the CERCA Programme/Generalitat de Catalunya. ICN2 acknowledges the support of the Spanish MINECO through the Severo Ochoa Centers of Excellence Program under Grant SEV-2013-0295

Adsorptive heat transformation systems such as adsorption thermal batteries and chillers can provide space heating and cooling in a more environmental friendly way. However, their use is still hindered by their relatively poor performances and large sizes due to the limited properties of solid adsorbents. Here, the spray-drying continuous-flow synthesis of a new type of solid adsorbents that results from combining metal-organic frameworks (MOFs), such as UiO-66, and hygroscopic salts, such as CaCl2 has been reported. These adsorbents, commonly named as composite salt in porous matrix (CSPM) materials, allow improving the water uptake capabilities of MOFs while preventing their dissolution in the water adsorbed; a common characteristic of these salts due to the deliquescence effect. It is anticipated that MOF-based CSPMs, in which the percentage of salt can be tuned, are promising candidates for thermal batteries and chillers. In these applications, it is showed that a CSPM made of UiO-66 and CaCl2 (38% w/w) exhibits a heat storage capacity of 367 kJ kg−1 , whereas a second CSPM made of UiO-66 and CaCl2 (53% w/w) shows a specific cooling power of 631 W kg−1 and a coefficient of performance of 0.83, comparable to the best solid adsorbents reported so far.

Metal-organic frameworks (MOFs) built up from connecting M-XF6 pillars through N-donor ligands are among the most attractive adsorbents and separating agents for CO2 and hydrocarbons today. The continuous, one-step spray-drying synthesis of several members of this isoreticular MOF family varying the anionic pillar (XF6 =[SiF6 ]2- and [TiF6 ]2- ), the N-donor organic ligand (pyrazine and 4,4'-bipyridine) and the metal ion (M=Co, Cu and Zn) is demonstrated here. This synthetic method allows them to be obtained in the form of spherical superstructures assembled from nanosized crystals. As confirmed by CO2 and N2 sorption studies, most of the M-XF6 -based MOFs synthesised through spray-drying can be considered "ready-to-use" sorbents as they do not need additional purification and time consuming solvent exchange steps to show comparable porosity and sorption properties with the bulk/single-crystal analogues. Stability tests of nanosized M-SiF6 -based MOFs confirm their low stability in most solvents, including water and DMF, highlighting the importance of protecting them once synthesised. Finally, for the first time it was shown that the spray-drying method can also be used to assemble hydrogen-bonded open networks, as evidenced by the synthesis of MPM-1-TIFSIX.

The outstanding electronic and physico-chemical properties of graphene make it an ideal filler in the fabrication of conducting and robust ceramic composites. In this study, a novel single-step approach for processing electrically conducting and well dispersed graphene/SiC nanocomposites is shown. These materials were processed by growing epitaxial graphene with either α- or β-phase SiC ceramics during their densification via spark plasma sintering (SPS). About 4 vol.% of few-layer graphene domains were generated in situ during the SPS process, leading to a conducting graphene network that significantly enhanced the electrical performance of SiC. The in situ graphene SPS growth mechanism arose from the combined action of the electric current, high temperature and partial vacuum. This approach offers unprecedented opportunities for the fast manufacturing of graphene/SiC nanocomposites with superior electrical and mechanical properties, precluding the handling of potentially hazardous nanostructures. This method widens their possible applications, including micro-electromechanical systems, brakes, micro-turbines or micro-rotors.

The structure of the new complex with molecular formula [Cu{(CH3)2SO}6]I4, has been determined. The compound comprises discrete [Cu{(CH3)2SO}6]2 + units connected through a self-assembly process with a linear arrangement of polyiodide I2n + 22 −, driven by non-classical hydrogen bonds C H∙∙∙I. The polyiodide chain presents a neutral I2 molecule weakly coordinated with two iodide anions. The linear, uncoordinated, centrosymmetric polyiodide anion represents a rare example of a tetraiodide.

This article analyses the role of language in the intra- and intergenerational social mobility of Argentinean, Colombian and Moroccan immigrants in Catalonia, an officially bilingual society. We start from the notion that the knowledge and use of and attachment to local languages are affected by the range and importance of opportunities for social mobility offered by the host society. Empirical evidence is based on 45 biographical interviews with members of first generation immigrant groups and their children (raised in Catalonia and currently living outside the family home). We show that the attitudes towards and use of the Catalan language depend on expectations and constraints with regard to upward social mobility. This article questions the causal relationship between languages spoken and job opportunities, postulated by means of the theory of human capital whereby language is only considered as a competitive advantage on the basis of its communicative value.

Metal-organic frameworks (MOFs) built up from connecting M-XF

Given the growing request for reusing raw material in new manufactured products in the plastics industry, the present study analyzes the effect of the concentration of recycled materials and pigments on the rheological properties of the polymer blend. It was quantified and analyzed in a statistical way the significance of the effects that these components produce in the rheological properties, such as the melt flow index, the maximum torque and the degradation time on high density polyethylene (HDPE). Knowledge of such properties will optimize processing parameters by using polymer blends with recycled materials and pigments. A minimum effect of the components was evidenced on the melt flow index having the pigment content the greatest impact factor.

Metal–organic frameworks (MOFs) are among the most attractive porous materials currently available. However, one of the challenges precluding their industrial exploitation is the lack of methods for their continuous production. In this context, great advances have been enabled by recently discovered, novel continuous-fabrication methods such as mechanosynthesis, electrochemistry, continuous-flow synthesis and spray-drying. Herein we report the benefits of coupling two of these processes—spray-drying and continuous flow—for continuous synthesis of MOFs assembled from high-nuclearity secondary building units (SBUs). Using the resulting spray-drying continuous flow-assisted synthesis, we have prepared numerous members of diverse MOF families, including the UiO-66, Fe–BTC/MIL-100 and [Ni8(OH)4(H2O)2(L)6]n (where L = 1H-pyrazole-4-carboxylic acid) series. Interestingly, all of these MOFs were automatically obtained as compact microspherical superstructures (beads). We anticipate that our strategy could be easily employed for synthesizing and shaping multivariate (MTV) MOFs.

El presente provee información básica a nivel departamental del desempeño sectorial, sus vínculos con la orientación de la ciencia, la tecnología, la innovación y las demandas del sector sobre conocimiento técnico para focalizar la investigación publica, articular capacidades, aunar esfuerzos para superar problemas productivos, mejorar la competitividad y aprovechar oportunidades del mercado en distintas cadenas de productividad priorizadas en el departamento.

Modulation of oxide properties in a direction perpendicular to surfaces can be easily achieved by advanced thin film deposition tools. In contrast, simultaneous nanoscale modulation of properties in directions perpendicular and parallel to surfaces, as required for building three-dimensional (3D) nanometric devices, has remained elusive. Though bottom-up approaches allow obtaining controlled lateral growth, these techniques fail to achieve long-range order or do not allow simultaneous modulation of properties in the perpendicular direction. Here, we show that, by exploiting a dual strategy based on the spontaneous surface restructuration of some perovskite substrates and the layer-by-layer growth of nanometric heteroepitaxial perovskite layers, surfaces with laterally modulated surface relief, chemical termination, electrostatic potential, and electrical conductance can be obtained. As illustrative examples, conducting ferromagnetic manganite La2/3Sr1/3MnO3 and ferroelectric BaTiO3 ultrathin films have be...

This article examines the effects of globalization dynamics on the use of Catalan among Latin American migrants living in Catalonia. The globalization process pushes towards an increasing mobility of workers and companies. Barcelona is one of the cities where this dynamic has been more evident in the last two decades, with big areas of the city being reshaped in order to suit the needs of global capital. At the same time, Catalonia has been receiving vast numbers of Latin American migrants who already speak Spanish, one of the official languages of the region, but not the other, Catalan. This article will examine the conflicting pressures experienced by those migrants both in the labor market and in their communities.

Graphene nanoplatelet (GNP)/silicon nitride (Si3N4) ceramic composites containing 12 and 15 wt.% of GNPs are prepared by mixing the nanoplatelets and the ceramic powders in a liquid medium followed by densification of the dried mixture by spark plasma sintering. The electrical conductivity of these composites is investigated at the nanoscale by conducting scanning force microscopy to understand the influence of the carbon phase content when above the percolation threshold. The establishment of a conducting network is revealed from the conduction measured at GNPs emerging at the surface of the composites. Current maps obtained for two orientations of the composites, parallel and perpendicular to the press sintering axis, show a preferential orientation of the nanoplatelets within the ceramic matrix. The effective current per conducting pixel, determined from the corresponding maps, is four times larger for the 15 wt.% GNP composite than for the 12 wt.% one. For the same composite (15 wt.%), differences in the effective current are measured for each of the two probing configurations. These results are interpreted in terms of unbalanced weight and nature of the resistors forming the percolated network.

The growth of Si homoepitaxial layers on Si(001) substrates by molecular beam epitaxy is analyzed for a set of growth conditions in which diverse nanometer-scale features develop. Using Si substrates prepared by exposure to HF vapor and annealing in ultra-high vacuum, a rich variety of surface morphologies is found for different deposited layer thicknesses and substrate temperatures in a reproducible way, showing a critical dependence on both. Arrays of 3D islands (truncated pyramids), percolated ridge networks, and square pit (inverted pyramid) distributions are observed. We analyze the obtained arrangements and find remarkable similarities to other semiconductor though heteroepitaxial systems. The nanoscale entities (islands or pits) display certain self assembly and ordering, concerning size, shape, and spacing. Film growth sequence follows the ‘islands–coalescence–2D growth’ pathway, eventually leading to optimum flat morphologies for high enough thickness and temperature.