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Blended cements are today commonly used for concrete structures built near the sea. When reinforced concrete is exposed to the atmospheric marine environment, it is necessary to consider steel corrosion caused by both, chloride ions and carbon dioxide. In this research, reinforced OPC and FA cement concrete samples have been tested in order to evaluate their comparative performance when exposed to chlorides, to CO2 and to both agents acting together. The techniques used to evaluate the steel corrosion rates have been the polarization resistance, intersection method of polarization curves, and electrochemical impedance spectroscopy. The results indicate a similar behavior of FA and OPC concrete for samples exposed to CO2. For the pure chloride exposure and the combined exposure regimes, the behavior depends on the type of binder. The polarization resistance technique appears to show some limitations when there is not enough electrolyte inside the pores.

Special foundations, most prominently micropiles and soil anchors, are frequently used in construction today. In Spain, the grout for these special technical applications is generally prepared with portland cement, although the codes and standards in place stipulate only the minimum compressive strength required, with no mention of cement type. Those texts also establish a range of acceptable water:cement ratios. In the present study, durability and compressive strength in cement grout prepared with blast furnace slag cement at different w/c ratios are characterised and compared to the findings for a reference portland cement grout. The results show that slag grout exhibits greater durability than the portland cement material and complies with the compressive strength requirements laid down in the respective codes. Actualmente es muy frecuente el empleo de cimentaciones especiales, entre las que destacan los micropilotes y los anclajes. En España, las lechadas de cemento para estos trabajos geotécnicos especiales se preparan habitualmente con cemento Portland, aunque las diferentes normativas al respecto no restringen el tipo de cemento a emplear, siempre que se alcance una determinada resistencia a compresión. Respecto a la dosificación de las lechadas, la normativa permite emplear diferentes relaciones agua/cemento dentro de un determinado rango. En vista de ello, en este trabajo se han caracterizado las propiedades de durabilidad y resistencia a compresión de lechadas de cemento preparadas con un cemento con escoria de alto horno y con diferentes relaciones a/c, tomando como referencia de comportamiento lechadas de cemento Portland. El uso de un cemento con escoria conlleva una mejora en la durabilidad de las lechadas, cumpliendo los requisitos de resistencia a compresión establecidos por la normativa. This research was funded by the Spanish Ministry of Economy and Competitiveness (formerly by the Spanish Ministry of Science and Innovation) and FEDER through projects BIA2010-20548 and BIA2011-25721.

Fundamentos La profundidad y duracion de la neutropenia y las caracteristicas de la enfermedad subyacente son factores determinantes en el pronostico del syndrome febril. Aunque clasicamente se ha considerado al trasplante de progenitores hematopoyeticos (TPH) como un productor de neutropenia de alto riesgo, probablemente la neutropenia observada en el TPH en algunos tumores solidos podria ser considerada de riesgo intermedio. Evaluamos episodios febriles en pacientes con estas caracteristicas Metodos Analizamos prospectivamente 132 TPH autologos, obtenidos de sangre periferica, en pacientes con cancer de mama (1994-1999) Acondicionamiento Stamp V. Profilaxis antibacteriana: ofloxacino (400 mg/12 h por via oral). Clasificacion del sindrome febril: bacteriemia, microbiologicamente documentado sin bacteriemia, infeccion clinica y fiebre de origen incierto Resultados Presentaron fiebre 122 pacientes (92%), edad media: 45 anos (rango: 27-61). Hubo 32 (26%) bacteriemias, 13 (11%) documentaciones microbiologicas sin bacteriemia y 54 (44%) infecciones clinicas. Mediana de dias con neutrofilos Conclusiones La excelente evolucion de nuestras pacientes permite considerar su neutropenia como deriesgo medio o bajo, lejos de las tasas de mortalidad por infeccion publicadas en otros tipos de trasplante hematopoyetico. El predominio de GN en los ultimos anos y su escasa sensibilidad a quinolonas debe hacer reconsiderar su uso profilactico en estas pacientes. Palabras clave: neutropenia febril, cancer de mama, trasplante de progenitores hematopoyeticos

A conditioning procedure is proposed allowing to install into the concrete specimens any selected value of water saturation degree with homogeneous moisture distribution. This is achieved within the least time and the minimum alteration of the concrete specimens. The protocol has the following steps: obtaining basic drying data at 50 C (water absorption capacity and drying curves); unidirectional drying of the specimens at 50 C until reaching the target saturation degree values; redistribution phase in closed containers at 50 C (with measurement of the quasi-equilibrium relative humidities); storage into controlled environment chambers until and during mass transport tests, if necessary. A water transport model is used to derive transport parameters of the tested materials from the drying data, i.e., relative permeabilities and apparent water diffusion coefficients. The model also allows calculating moisture profiles during isothermal drying and redistribution phases, thus allowing optimization of the redistribution times for obtaining homogeneous moisture distributions. © 2012 RILEM., We thank the funding received for this research from the Ministerio de Ciencia e Innovación and Ministerio de Economía y Competitividad of Spain and Fondo Europeo de Desarrollo Regional (FEDER) through project BIA2010-20548, and from the Ministerio de Fomento of Spain through project C34/2006. Authors would like to thank Holcim España, S.A. for providing the cement and aggregates, and Sika S.A.U. España for the superplasticizer, needed for this research.

Con esta iniciativa pionera en España, desarrollada por parte de la empresa DKV Seguros, se busca que la presencia del arte llene el Hospital de Dénia y forme un entorno mas humanizado. Así, junto a la Colección DKV: Arte y Salud, se muestra un importante proyecto escultórico, así como la intervención pictórica mural llevada a cabo en el área de Pediatría y desarrollada por un reconocido colectivo de Urban Art. Además, el proyecto cuenta con una Sala de Exposiciones dentro del propio hospital, que bajo el leivmotiv de Arte y Salud, programará exposiciones anuales, de producción propia y también en colaboración con distintas entidades públicas y privadas. Todo este proyecto se completa con un programa de actividades para pacientes de las distintas áreas del hospital: hemodiálisis, quimioterapia, psiquiatría y pediatría. Durante la semana se desarrollan talleres de teatro, musicoterapia y arteterapia, así como diversas intervenciones murales efímeras mientras los pacientes están recibiendo sus tratamientos. Un programa de arte al servicio de la salud, donde la humanización del entorno, el dialogo entre las diferentes disciplinas del arte y la medicina, serán la base de desarrollo del proyecto. With this initiative, pioneer in Spain, developed by DKV Seguros, the hospital is imbued with art in order to make a more humanized environment. This way, with DKV Collection: Art and Health, an important sculpture project is held as well as the wall paintings in the pediatric area, developed by an important Urban Art group. Besides, the project has an Exhibition Room, which, under the slogan of Art and Health, will hold annual exhibitions of self production as well as exhibitions in collaboration with different public and private institutions. This whole project is completed with a program of activities for patients of different areas: hemodialysis, chemotherapy, psychiatry and pediatrics. During the week drama workshops, music therapy and art therapy activities are developed at the hospital, as well as ephemeral wall paintings while patients are receiving their treatments. It is an art program at the service of health, where the humanization of the environment, the dialogue between different art disciplines and medicine will be the foundation upon which this project will be developed.

The adsorption and oxidation of L(+)-ascorbic acid on bare and Bi-covered Pt electrodes in a sulfuric acid medium have been studied by cyclic voltammetry and in situ FTIR spectroscopy. The latter technique has allowed the direct detection of COads from ascorbic acid adsorption, both at open-circuit and controlled potential, for the bare Pt surface. Under these latter conditions both linearly bonded and multi-bonded CO were detected. The existence of other strongly adsorbed species which are oxidized in the oxygen adsorption region has been demonstrated by cyclic voltammetry. The formation of all these adsorbed species is completely suppressed on the Bi-covered Pt surface under UPD conditions. Ascorbic acid oxidation was monitored by following the variation of the IR spectra in the presence and in the absence of Bi3+ in solution. The electrocatalytic effect of the Bi adlayer can be explained mainly through the suppression of any dissociative adsorption step leading to the formation of strongly adsorbed species.

In recent years the use of active additions on cement, like ground ­granulated blast-furnace slag, has become very popular because they have many environmental benefits. In this work, the behaviour of mortars made with two different cement types, an ordinary Portland cement and a slag cement, was tested. These mortars were exposed to two different environmental conditions during their hardening, an optimum laboratory condition and a Mediterranean climate environment with lower relative humidity. The development of the microstructure of mortars and the changes of their service properties were studied at different hardening ages until 90 days. The mortars made with slag cement have shown a good behaviour compared with ordinary Portland cement mortars. The relative humidity has an influence on properties of both cements studied. As a preliminary conclusion, cements with slag hardened under environmental conditions of a Mediterranean climate, can have good service properties at early hardening ages, even better than Portland cement.

The voltammetric behaviour of the three basal Pt orientations (100), (110) and (111) in neutral phosphate buffered solutions are presented and discussed. The voltammograms corresponding to the hydrogen adsorption-desorption reaction and the influence of oxygen monolayer adsorption on these faces show some similarities with the corresponding results in acid media; in general they are intermediate between those observed in sulphuric and perchloric acids. The electric charges measured in the hydrogen adsorption- desorption potential range are higher than the corresponding theoretical values of the unreconstructed surfaces, particularly in the cases of Pt(100) and Pt(111). This is interpreted as being due to a reconstruction of the Pt(100) surface towards the (5 × 20) structure. For Pt(111) hydrogen is adsorbed in two separate potential ranges; however, the excess charge found for the state at higher potential suggests that oxygenated species are present on the surface in this range. The adsorption of bromide ions suppresses the adsorption of oxygenated species. In contrast, the Pt(110) orientation seems to experience a lower degree of initial reconstruction to a (1 × 2) structure in neutral phosphate buffer than in sulphuric acid, but it shows a progressive reconstruction of the type mentioned above upon cycling in a potential range including oxygen adsorption-desorption.

At present the most efficient fire extinguishers are power ones. Fireextinguishing powders of serial production do not fulfill modern requirements, primarily from the viewpoint of their universal and practical use. It must be noted that most of them contain halogen, and it is established that penetration of halogens into the atmosphere causes a breaking of the ozone layer. The main goal of investigation presented in this paper is development of non-halogen, non toxic, environmentally-friendly, highly-efficient, inexpensive, universal, composite fire-extinguish powders based on domestic mineral raw materials such as clay shale, zeolite and perlite. The proposed method of obtaining composite powders does not require the following expensive chemical processing and modification with halogen-inclusive hydrofobizative additives. Hence, these composite powders will be cheaper (1,5-2 times) than powders of serial production. The raw materials: clay shale, zeolite, perlite were selected according to high operating properties, which are indicative of a reduction of burning processes. The powders must not only be effective during the fire extinguish, but also they must maintain those properties, which decrease the extinguishing effect after small changes in properties. The effectiveness of powders is defined not only according to their dispersity and inhibition ability, but also according to their storage and transportation conditions. These conditions are defined by the exploitation properties of powders. The most important among them are: consolidation and caking, dispersity, tendency of humidity, flow and storage duration. We studied the performance properties of zeolite, perlite and clay shale and composite powders based on such materials and established dependence of tendency to consolidation and caking on dispersity. Accordingly, the dispersity of composite powders was selected in such a way that the tendency of consolidation and caking was minimal. At the same time particle size should be relevant towards the rapid head and destruction, so that we have a homogenous effect and heterogeneous inhibition.

Real structures are hardened in conditions different from the optimum laboratory conditions, where materials are usually tested. The different temperature, and especially the different relative humidity present in the environment, may cause a different microstructure and, as a consequence, different service properties. In this work mortars made with two different cement types are tested in laboratory conditions and at a lower relative humidity. These new environmental conditions cause a slower microstructural development and different durability and mechanical properties at early hardening ages.

With the aim of increasing the efficiency of an Fe/Cr redox flow battery, the behaviour of the Cr(III)/Cr(II) redox reactions and the hydrogen evolution on goldgraphite electrodes has been studied. Different metals with high hydrogen overvoltage have been used. An enhancement in the reversibility of the redox couple is produced with these types of goldgraphite electrodes, though the energetic efficiency of a monopolar Fe/Cr redox cell constructed with these electrodes is not improved due to the greater hydrogen evolution presented by the goldgraphite electrodes in relation with graphite electrodes.

[EN]This paper presents the results of a Round-Robin Test on methods for determining chloride transport parameters in concrete, carried out by the Technical Committee TC 178-TMC: “Testing and Modelling Chloride Penetration in Concrete” in which 27 different laboratories around the world have participated, using 13 different methods, in triplicate specimens, for 4 different mixes of concrete cast with different binders. Four different groups of methods have been tested: Natural diffusion methods (D), Migration methods (M), Resistivity methods (R) and Colourimetric methods (C). The statistical treatment of the data has been carried out according to the International Standard ISO 5725-2:1994 for the determination of the accuracy (trueness and precision) of measurement methods and results. Part 2: Basic method for the determination of the repeatability and reproducibility of a standard measurement method. In order to make an evaluation of these methods, four indicators have been identified and within each of them, several sub-indicators have been assigned. According to this system of classification, the methods have been classified following each indicator (trueness, precision, relevance and convenience), and also globally, by assigning different factors of importance, F.I., to the different indicators., [FR]Cet article comprend les résultats des essais inter-laboratoires sur les méthodes de mesure de la pénétration des chlorures dans le béton, effectués par la Commission technique RILEM 178-TMC: “Testing and Modelling Chloride Penetration in Concrete”. Les participants étaient issus de 27 laboratoires répartis sur différents continents. On a utilisé 4 mélanges de béton différents fabriqués avec différents types de ciment, ainsi que␣13 méthodes d’essais utilisant des échantillons en triple exemplaire. Les méthodes d’essais ont été divisées en 4 familles: essais de Diffusion naturelle (D), essais de Migration (M), essais de Résistivité électrique (R) et méthodes Colorimétriques (C). Le traitement statistique a été fait conformément à la norme Standard ISO 5725-2:1994 intitulée: «Determination of the accuracy (trueness and precision) of measurement methods and results. Part 2: Basic method for the determination of the repeatability and reproducibility of a standard measurement method (Détermination de la précision des méthodes de mesure et des résultats. Partie 2: Méthode essentielle de détermination de la répétabilité et de la reproductibilité d’une méthode classique de mesure)». Pour faire une analyse plus détaillée, on a complété l’étude avec l’évaluation de 4 indicateurs d’intérêt et plusieurs sous-indicateurs. L’évaluation finale a été effectuée au moyen de la classification de l’importance des données de chaque indicateur en tenant en compte des facteurs d’importance.

In this study, the durability-related properties of mortars prepared using two types of cement with different contents of fly ash were tested. One of the most important ways of ingress of aggressive substances in cementitious materials is through water. Therefore, to characterize their durability, the capillary suction and the resistance against chloride ingress of the fly ash mortars were studied. The mortars were exposed to four different constant temperatures and relative humidities (RHs) for 365 days. The measured properties of both cement types were affected by the hardening environment. For each environment studied, the durability-related parameters of the fly ash cement mortars studied were quite similar at high hardening ages, independent of their fly ash content. In spite of the different resistance classes of cements used, the durability related properties of both cement types were similar at high hardening ages, regardless of the environment.

Etude voltammetrique de la reduction des nitrates sur une electrode d'or partiellement recouverte de plomb par suite de l'adsorption d'ions PB 2+ , en solution acide

Electrochemical techniques can be used to arrest or prevent reinforced concrete corrosion. This article reports on a study that evaluated the effect of the type of anodic arrangement on the efficiency of the technique of electrochemical chloride removal (ECR) applied to reinforced concrete structures. Two different arrangements were tested for maintaining the electrolytic medium in contact with the concrete surface: complete immersion of the system (structure and anode) in water during the electrochemical treatment; and the wrapping of the concrete structure with a sandwich-like anodic system, which consisted of two layers of polypropylene felt embedding the anodic material. Results demonstrate that the efficiency of an ECR treatment applied with a sandwich-like anodic system may be practically equal to that obtained with a liquid electrolyte (immersion) if a good contact between the concrete surface and the polymeric system is ensured. The use of a continuous graphite felt for the sandwich-like anodic system, instead of a discontinuous and more rigid metallic wire mesh anode, makes it easier to achieve the necessary electrical contact. The authors caution that the net influence of carbonation on the efficiency of ECR may vary for different experimental conditions.