Structured fibrous carbon-based catalyst for continuous nitrate removal from natural water

[EN] Bimetallic (Pd–Cu, Pd–Sn) nanoparticles supported on structured fibrous carbons (activated carbon fibers and carbon nanofibers grown on sintered metal fibers) were tested in nitrate removal of natural polluted water by hydrogen (a batch and continuous mode). Dependence of the activity/selectivity on catalyst chemical composition, promoter nature and metal particle size was studied. Sn-modified Pd nanoparticles showed higher N2 selectivity as compared to Cu-modified ones. The structured (Pd–Sn) nanoparticles supported on carbon nanofibers grown on Inconel sintered metal fibers demonstrated the best catalytic performance in an open flow reactor, providing optimal hydrodynamics properties.This work was carried out with the financial support of the European Community's Seventh Framework Programme (FP7/2007-2013) under grant agreement no. 226347.Yuranova, T.; Franch Martí, C.; Palomares Gimeno, AE.; García-Bordejé, E.; Kiwi-Minsker, L. (2012). Structured fibrous carbon-based catalyst for continuous nitrate removal from natural water. Applied Catalysis B: Environmental. 123-124:221-228. https://doi.org/10.1016/j.apcatb.2012.04.007S221228123-12

Algorithmic Superactivation of Asymptotic Quantum Capacity of Zero-Capacity Quantum Channels

The superactivation of zero-capacity quantum channels makes it possible to use two zero-capacity quantum channels with a positive joint capacity for their output. Currently, we have no theoretical background to describe all possible combinations of superactive zero-capacity channels; hence, there may be many other possible combinations. In practice, to discover such superactive zero-capacity channel-pairs, we must analyze an extremely large set of possible quantum states, channel models, and channel probabilities. There is still no extremely efficient algorithmic tool for this purpose. This paper shows an efficient algorithmical method of finding such combinations. Our method can be a very valuable tool for improving the results of fault-tolerant quantum computation and possible communication techniques over very noisy quantum channels.Comment: 35 pages, 17 figures, Journal-ref: Information Sciences (Elsevier, 2012), presented in part at Quantum Information Processing 2012 (QIP2012), v2: minor changes, v3: published version; Information Sciences, Elsevier, ISSN: 0020-0255; 201

Evidence update on prevention of surgical site infection

Purpose of review: surgical site infection (SSI) is a common health care associated infection and complicates up to 10-20% of operations with considerable health care resources. Apart from the widely adopted use of appropriate hair removal, antibiotic prophylaxis, avoidance of hypothermia and peri-operative glycaemic control to reduce SSIs this review has considered new research and systematic reviews, and whether their findings should be included in guidelines. Recent findings: The efficacy of preoperative bathing/showering, antibiotic prophylaxis for clean surgery and perioperative oxygen supplementation to reduce the risk of SSI is still in doubt. By contrast, the use of 2% chlorhexidine in alcohol skin preparation, postoperative negative pressure wound therapy and antiseptic surgical dressings do show promise. Antimicrobial sutures in independent meta-analyses were found to reduce the risk of SSI after all classes of surgery (except dirty) whereas the use of wound guards, or diathermy skin incision (compared with scalpel incision), did not. Summary: The incidence of SSI after surgery is not falling. Based on this review of published trials and evidence-based systematic reviews some advances might be included into these care bundles. More research is needed together with improved compliance with care bundles

Tratamiento de efluentes acuosos contaminados con compuestos organoclorados

[ES] Los compuestos organoclorados son un tipo de residuos que han adquirido especial relevancia en los últimos tiempos, debido a sus características tóxicas y peligrosas, tanto para el medio ambiente como para los seres humanos. Su especial peligrosidad ha potenciado la búsqueda de alternativas para su tratamiento en las distintas corrientes donde se presentan. En este artículo se describe la problemática real de este tipo de compuestos, se exponen los principales contaminantes y se muestra una visión general de las alternativas para la eliminación de estos organoclorados de corrientes acuosas, detallándose en profundidad una de las alternativas de eliminación consideradas: la hidrodecloración catalítica en fase acuosa.Padilla Vivas, B.; Díez Sanz, FV.; Ordóñez García, S. (2005). Tratamiento de efluentes acuosos contaminados con compuestos organoclorados. 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Transesterification of palm oil using KF and NaNO3 catalysts supported on spherical millimetric γ-Al2O3

The use of spherical millimetric gamma-alumina (γ-Al2O3) as a catalyst support for the production of biodiesel from palm oil is demonstrated. The catalyst support was produced using a dripping method, and KF and NaNO3 catalysts were loaded on the support using the impregnation method. X-ray diffraction (XRD) analysis showed the formation of Na2O and NaAlO2 phases on the NaNO3/γ-Al2O3 catalyst and the formation of K2O and KAlF4 on the KF/γ-Al2O3 catalyst, which were possibly the active sites for the transesterification reaction. The highest number and strength of basic sites generated from the solid phase reaction of the KF/γ-Al2O3 catalyst loaded with 0.24 g kF/g γ-Al2O3 and the NaNO3/γ-Al2O3 catalyst loaded with 0.30 g NaNO3/g γ-Al2O3 were confirmed by temperature programmed desorption of CO2 (CO2-TPD) analysis. The nitrogen adsorption–desorption isotherms also revealed a mesoporous structure of the catalysts. The biodiesel yield was comparable to that produced from smaller catalysts, and this result indicated the potential of the macrospherical catalysts

Studies on design of heterogeneous catalysts for biodiesel production

The production of biodiesel is gaining momentum with the ever increasing demand of the fuel. Presently, limited literature is available with respect to well designed solid heterogeneous catalyst for biodiesel production considering all the characteristics, process and operation parameters. Hence, a study was conducted to design effective heterogeneous catalyst for biodiesel production. Further, the significant impact of different catalysts, different feed stock, various reaction conditions such as temperature, methanol oil molar ratio, catalyst concentrations and stability/inactivation of the catalysts, are detailed out for transesterification process of biodiesel production. Based on the studies it can be concluded that well designed heterogeneous catalyst can yield high throughput of biodiesel