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Ca 3− x Na x Co 4 O 9 polycrystalline thermoelectric ceramics with small amounts of Na ( x =0, 0.01, 0.03, 0.05, 0.07, and 0.10) have been prepared using the classical solid state method. Microstructural characterization has shown that Na has been incorporated into the Ca 3 Co 4 O 9 phase and that no Na-based secondary phases have been produced. It has also been found that Na addition promotes grain growth and favours sintering due to the formation of a small amount of liquid phase. Electrical resistivity decreases when Na content increases until 0.07Na addition while Seebeck coefficient is maintained practically unchanged. The improvement in electrical resistivity leads to higher power factor values than the usually obtained in samples prepared by more complex and expensive techniques. [ABSTRACT FROM AUTHOR]

Abstract: Ca3−x Ga x Co4O y polycrystalline thermoelectric ceramics with small amounts of Ga have been synthesized by the classical solid state method. XRD data have shown that all the Ga has been incorporated into the Ca3Co4O9 and Ca3Co2O6 thermoelectric phases and no Ga-containing secondary phases have been produced. Moreover, for Ga contents ≥0.07, the Ca3Co2O6 phase disappears. Apparent density measurements have revealed that all samples are very similar, with densities around 70% of the theoretical one. Electrical resistivity decreases in all Ga-doped samples, compared with the pure ones, while the Seebeck coefficient is practically the same for all samples, except for the 0.12 and 0.15 Ga substituted ones, at high temperatures which present slightly higher values. Both factors in the 0.15 Ga-substituted samples lead to power factor values around 0.35mW/K2 m at 800°C which is about 70% higher than the values obtained for the undoped samples. [Copyright &y& Elsevier]

Highlights: [•] Ca has been substituted by Sr in small proportions in Ca3Co4O9. [•] Sr addition increases carrier concentration. [•] Room temperature resistivity decreases about 25% for 0.07 Sr addition. [•] Maximum power factor at 800°C reaches 0.30mW/K2 m for 0.07 Sr substituted samples. [ABSTRACT FROM AUTHOR]

Bi2Ba2Co2Ox thermoelectric ceramics were textured from the melt using the laser floating zone method, at a growth rate of 5mmh−1. The microstructure showed good grain alignment with the growth axis. These microstructural features are reflected in the thermoelectric performance, with a significant increase in the power factor values, reaching ∼0.4mWK−2 m−1 at 650°C, much higher than the values typically obtained in these materials. [ABSTRACT FROM AUTHOR]

Abstract: In the last decade, as computing power has increased, there has been an explosion in the use of eddy-resolving numerical methods in the engineering, earth and environmental sciences. For complex geomorphic flows, where accurate field investigations are difficult to perform and where experiments may be difficult to scale, these numerical approaches are beginning to give key insights into the nature of these flows. Eddy-resolving methods such as Large and Detached Eddy Simulation (LES/DES) may be contrasted with the time-averaged, three-dimensional simulations that only really began to be applied seriously in geomorphology fifteen years ago. While the potential of LES for geomorphology has been examined previously, DES is a relatively recent method that deserves further consideration. In this paper, we explain the method and then utilise examples from meander and confluence flows, as well as flow near the bed of a gravel bed river, to highlight the improvements to both the representation of the mean flow, and to the representation of time-varying processes, that result from the use of LES/DES. Some suggestions are provided for the future use of such techniques in geomorphology. [Copyright &y& Elsevier]

Abstract: Two solution synthetic methods, sol–gel and a polymeric route, have been studied in order to obtain Ca3Co4O9 misfit compounds with improved thermoelectric properties, compared to the classical solid state reaction. A comparison among the final products obtained by these different methods has been performed using DTA, TGA, FTIR, X-ray diffraction, scanning electron microscopy, and thermoelectric characterizations. All the samples obtained by solution synthesis show a very significative reduction on the secondary phases content. As a consequence, an important decrease on the electrical resistivity values is produced, compared to the solid state prepared samples, leading to a relatively important power factor raise. [Copyright &y& Elsevier]

Abstract: Bi2−x Pb x Sr2CaCu2O y textured materials (x =0.0, 0.2, 0.4, and 0.6) have been successfully prepared by the laser floating zone technique. Microstructure and electrical properties (J C and T C ) have been clearly affected by Pb addition. From the E–I curves, slope of the transition between the superconducting and the normal state (n) at 77K reaches a maximum of about 16 for the 0.4 Pb doped samples. This value is much higher than the typical ones for the Bi-2212 materials. Moreover, when the electrical properties of the 0.4 Pb doped samples are measured at lower temperatures (between 65 and 77K), n values increase when the temperature is decreased. A maximum n value of 32 has been reached at 65K which makes this material very attractive for its use as resistive fault current limiters. [Copyright &y& Elsevier]

Abstract: Bi1.6Pb0.4Sr2Co1.8O x thermoelectric ceramics with small Ag additions (0, 1, and 3wt%) have been successfully grown from the melt, using the laser floating zone method. Microstructure has shown a reduction in the amount of secondary phases and a better grain alignment with respect to the growth direction for an Ag content of 3wt%. The microstructural evolution, as a function of Ag content, is confirmed with the electrical resistivity values, which show an important decrease for the 3wt% Ag samples, leading to maximum power factor values of about 0.42mW/K2 m at 650°C, which are among the best results obtained in this type of material. [Copyright &y& Elsevier]

Abstract: Bi2Sr2Co1.8O x /Ag composites with small amounts of Ag have been synthesized by a sol–gel via nitrates reaction and directionally grown from the melt. Some of the obtained samples were annealed in order to obtain the thermoelectric phase as the major one. As-grown and annealed samples were microstructurally characterized to determine the phases distribution and alignment. Moreover, thermoelectric and mechanical characteristics of annealed samples were determined by the four-probe technique and by three point flexural strength tests, respectively. Scanning electron microscopy revealed that Ag particles appear dispersed among well oriented ceramic grains with large size, providing a plastic flow region which increases the flexural strength for the optimally Ag added samples (1wt.%). The composites electrical resistivity is lower than that of pure Bi2Sr2Co1.8O x while Ag addition does not significantly affect thermopower values. The resistivity reduction leads to power factor improvements of ∼50%, compared with pure samples, for Ag additions of 1wt.% Ag. [Copyright &y& Elsevier]

Abstract: The effect of annealing on directionally solidified Bi2Sr2Co1.8O x ceramic rods has been studied for different times up to 1008h. Microstructure has shown five different phases in the as-grown materials which have been reduced to two major ones after 1008h thermal treatment, accompanied by an important grain growth. These microstructural changes are reflected on the mechanical properties which are higher than those measured in the as-grown materials in all cases. Moreover, they also produce an important decrease on the resistivity and increase of thermopower, leading to a raise on the power factor on thermally treated samples, about two times, compared to the as-grown samples. [Copyright &y& Elsevier]

Summary: Introduction: The face is the area most vulnerable for dog bites in children. Surgical management is an emergency to prevent infection, functional and aesthetic outcomes. The aim of this study was to define a new gravity scale, and to determine a prevention policy. Patients and methods: In our maxillofacial and plastic surgery department, we conducted a retrospective study from 2002 to 2010, including 77 children under 16years old, victims of facial dog bite. We analyzed epidemiological, clinical data, surgical outcomes. Results: The mean age was 5.36years. Dogs were principally represented by class I and II dogs; 27,7% of them had ever bitten before. In almost all the cases, the dogs belong to the family or closers. Twenty-one percent of children belong to an unfavourable social environment; 71.43% of dog bites interested the central area of the face. The bites were deep in 77% of cases with amputation or extensive loss of substance in 31% of cases. The healing time was 10.54months. Nearly a third of patients required several surgeries; 41.56% of patients had aesthetic and functional sequelae; 35.1% of children had psychological problems afterward. Conclusion: Facial children dog bites require a multidisciplinary approach, and a long-term follow-up. We propose a new classification of dog bite severity, more appropriate to the face. [ABSTRACT FROM AUTHOR]

Bi2Ca2Co1.7O x nominal composition ceramic rods were textured by the electrically assisted laser floating zone technique. A new composite formed by three phases, two of them with well-known thermoelectric properties, Bi2Ca2Co1.7O x and Ca3Co4O9, was obtained for the first time when the growth process was performed with a 300mA applied current. Under these conditions the thermoelectric performances of this new composite reach values above the highest ones reported in the literature for polycrystalline Bi2Ca2Co1.7O x materials. [ABSTRACT FROM AUTHOR]

Abstract: High-performance Ca3Co4O9 thermoelectric ceramic has been prepared from a Ca1−x Co x O/Ca y Co1−y O divorced eutectic structure produced by a directional melt-grown using the laser floating zone technique. This material has been grown at very high solidification rate in order to produce a very fine microstructure to reduce the necessary annealing time to recover the Ca3Co4O9 thermoelectric phase as the major one. As-grown and annealed samples were microstructurally characterized to determine the phases and estimate the extent of Ca3Co4O9 formation with time and related with their thermoelectric performances. The optimum annealing time, 72h, has been determined by the maximum power factor value (about 0.42mWK−2m−1), which is around the best values reported in textured materials (∼0.40mWK−2m−1). This high power factor outcome from the high Ca3Co4O9 phase content, apparent density and Co3+/Co4+ relationship determinations performed in the present work. [Copyright &y& Elsevier]

Abstract: Ca3Co4−x Cr x O9 polycristalline thermoelectric ceramics with small amounts of Cr have been synthesized by the classical solid state method. Microstructural characterizations have shown that all the Cr has been incorporated into the Ca3Co4O9 structure and no Cr-containing secondary phases have been produced for Cr contents≤0.05. Apparent density measurements have shown that all samples are very similar, with densities around 75% of the theoretical one. Electrical resistivity decreases and Seebeck coefficient slightly raises when Cr content increases until 0.05 Cr addition. The improvement in both parameters leads to higher power factor values than the usually obtained by conventional solid state routes. [Copyright &y& Elsevier]

Summary: Animal bite is frequently involved in children labial defect. The need for labial surgical repair is to restore anatomy and function. Local and regional flap is usually described for labial reconstructions. Few authors recommend mucosal and skin graft. In the present study, we described skin and mucosal graft for reconstruction of complex labial defect. This surgical technique can be applied in very young children with reasonable expectations of excellent functional and aesthetic outcome. [ABSTRACT FROM AUTHOR]

Summary: Introduction: Orbital fractures represent 30 % of children facial fractures. Nausea and vomiting are more predictive of entrapment than local trauma stigmatisms. Entrapment and diplopia are more frequent in adults. Delay for surgery is unclear in literature varying from 6 hours to days. The aim of this study is to summarise the aspects of orbital floor fractures in children with regard to clinical and radiological presentation, management, and outcomes. Patients and methods: We conducted a retrospective study including 34 children presenting isolated orbital floor fracture. Clinical, radiological, ophthalmological, surgical data and outcomes were analyzed. Results: Mean age was 9.4 years. In 15% of cases, no local stigmatism of trauma was present. Entrapment fracture was the most frequent, with 81% of fat or muscles entrapment. In all, 27% of the patient had residual diplopia. Residual diplopia developed after trap-door fracture with muscle entrapment and a more than 24hours delay for surgery. Conclusion: Trap-door fracture is frequent in childhood population. Clinical diagnosis can be difficult. However, surgical treatment should be considered before 24hours to avoid complication as residual diplopia. [ABSTRACT FROM AUTHOR]