Production of gaseous and liquid bio-fuels from the upgrading of lignocellulosic bio-oil in sub- and supercritical water: effect of operating conditions on the process

This work analyses the influence of the temperature (310–450 C), pressure (200–260 bar), catalyst/biooil mass ratio (0–0.25 g catalyst/g bio-oil), and reaction time (0–60 min) on the reforming in sub- and supercritical water of bio-oil obtained from the fast pyrolysis of pinewood. The upgrading experiments were carried out in a batch micro-bomb reactor employing a co-precipitated Ni–Co/Al–Mg catalyst. This reforming process turned out to be highly customisable for the valorisation of bio-oil for the production of either gaseous or liquid bio-fuels. Depending on the operating conditions and water regime (sub/supercritical), the yields to upgraded bio-oil (liquid), gas and solid varied as follows: 5–90%, 7–91% and 3–31%, respectively. The gas phase, having a LHV ranging from 2 to 17 MJ/m3 STP, was made up of a mixture of H2 (9–31 vol.%), CO2 (41–84 vol.%), CO (1–22 vol.%) and CH4 (1–45 vol.%). The greatest H2 production from bio-oil (76% gas yield with a relative amount of H2 of 30 vol.%) was achieved under supercritical conditions at a temperature of 339 C, 200 bar of pressure and using a catalyst/bio-oil ratio of 0.2 g/g for 60 min. The amount of C, H and O (wt.%) in the upgraded bio-oil varied from 48 to 74, 4 to 9 and 13 to 48, respectively. This represents an increase of up to 37% and 171% in the proportions of C and H, respectively, as well as a decrease of up to 69% in the proportion of O. The HHV of the treated bio-oil shifted from 20 to 35 MJ/kg, which corresponds to an increase of up to 89% with respect to the HHV of the original bio-oil. With a temperature of around 344 C, a pressure of 233 bar, a catalyst/bio-oil ratio of 0.16 g/g and a reaction time of 9 min a compromise was reached between the yield and the quality of the upgraded liquid, enabling the transformation of 62% of the bio-oil into liquid with a HHV (29 MJ/kg) about twice as high as that of the original feedstock (17 MJ/kg)

Continuous direct compression as manufacturing platform for sustained release tablets

This study presents a framework for process and product development on a continuous direct compression manufacturing platform. A challenging sustained release formulation with high content of a poorly flowing low density drug was selected. Two HPMC grades were evaluated as matrix former: standard Methocel CR and directly compressible Methocel DC2. The feeding behavior of each formulation component was investigated by deriving feed factor profiles. The maximum feed factor was used to estimate the drive command and depended strongly upon the density of the material. Furthermore, the shape of the feed factor profile allowed definition of a customized refill regime for each material. Inline NIRs was used to estimate the residence time distribution (RTD) in the mixer and monitor blend uniformity. Tablet content and weight variability were determined as additional measures of mixing performance. For Methocel CR, the best axial mixing (i.e. feeder fluctuation dampening) was achieved when an impeller with high number of radial mixing blades operated at low speed. However, the variability in tablet weight and content uniformity deteriorated under this condition. One can therefore conclude that balancing axial mixing with tablet quality is critical for Methocel CR. However, reformulating with the direct compressible Methocel DC2 as matrix former improved tablet quality vastly. Furthermore, both process and product were significantly more robust to changes in process and design variables. This observation underpins the importance of flowability during continuous blending and die-filling. At the compaction stage, blends with Methocel CR showed better tabletability driven by a higher compressibility as the smaller CR particles have a higher bonding area. However, tablets of similar strength were achieved using Methocel DC2 by targeting equal porosity. Compaction pressure impacted tablet properties and dissolution. Hence controlling thickness during continuous manufacturing of sustained release tablets was crucial to ensure reproducible dissolution. (C) 2017 Elsevier B.V. All rights reserved

Predictors of unintentional childhood injuries seen at the Accident and Emergency Units of three tertiary health care centres in Jos

Background: Unintentional childhood injuries pose a major health challenge especially in developing countries.Aim: This study sought to determine the predictors of unintentional childhood injuries in the three tertiary health centres studied.Methods: The study was a cross- sectional study. Sociodemographic data, history and physical examination, type of injury and the outcomes were obtained using structured questionnaire. Results: A total of 174 children were enrolled, 108 (62.1%) were males and 66 (37.9%) were females; 63 (36.2%) were < 5years while 65 (37.4%) were>10 years. Of the injuries observed; 99 (56.9%) were by vehicular objects, 15 (8.6%) were burns, 41 (23.6%) were from falls and 19 (10.9%) poisoning. Those who were treated as outpatients were 141 (81.0%) and 25 (14.4%) were admitted for inpatient care. About ninety four percent (94.3%) of the children had no significant effect or disability, 3.4% had short-term disability while 2.3% had long term disabilities or died post-injury. There was no statistically significant relationship between the age of the subjects, gender, duration of the injury prior to presentation and the educational status of their care givers with the pattern of the injury.Conclusion: This study showed that 81% (141) of the children studied were treated as outpatients, 56.9% were by vehicular objects, 62.1% were in males and the pattern of injuries were not related to age, gender, educational status of care givers, place or time of injuries. There is need to incorporate these findings in the provision of preventive messages in school health services and in the interventions targeting the safety of children against injuries. Further studies to identify risk factors and plan necessary interventions will also be necessary.Keywords: Predictors, unintentional, childhood injuries, emergency departments, out-patient, tertiary health centre

Valoración eco-pastoral de los pastos del Monte Lakora (Navarra, Pirineo occidental)

7 páginasSe aplica el método del índice eco-pastoral, desarrollado en trabajos previos, a los pastos del monte Lakora (Navarra) situado en el Pirineo occidental. Se ha utilizado un mapa de vegetación digitalizado (escala 1/5.000). Las comunidades de Primulion intricatae, Nardion strictae, brezales subalpinos de Vaccinium uliginosum y pastos de Festuca eskia son los que tienen un mayor valor ecológico. Las comunidades de Bromion erecti y Primulion intricatae son las que tienen un mayor valor pastoral potencial. El monte Lakora presenta un valor ecológico mayor que el pastoral, por lo que se justifica su inclusión dentro del Lugar de Importancia Comunitaria (LIC) “ES2200001 Larra-Aztaparreta” así como la priorización de su conservación mediante el adecuado manejo ganadero.Peer reviewe

Accumulation et effets des éléments métalliques sur les populations végétales spontanées de trois crassiers métallurgiques : peut-on utiliser les plantes comme bioindicateurs ?

National audienceThe actual risk of metals doesn't depend on their total concentrations, but rather on their bioavailability and own toxicity, it is important to get suitable tools for evaluating bioavailability and ecological effects of metals in situ. In this context, characterization of bioindicators of soil quality is a challenging issue. In this work, we hypothesized that plants colonizing metal-contaminated soils could be an efficient tool to assess both the bioavailability of metals, and their effect on local ecosystem. To check this hypothesis, we studied spontaneous vegetation colonizing three metallurgical landfills characterised by different total and extractible heavy metals fractions (Table 1), both in terms of metal accumulation in leaves and of phytosociological associations. Results (Tables 2 and 3) showed that for two out of the three studied sites, leaf metals in native plants were closely comparable to normal concentrations found in plants growing in uncontaminated soil, while for the third site average levels in Cr, Cu, Ni, Pb and Zn were significantly higher. Thus, measurements of leaf metals clearly discriminated the studied sites, with respect to actual metal phytoavailability. Botanical survey of the three study sites showed that the vegetation was quite normal, with common species, their associations were unusual and, among the four major plant groups we identified, three of them had never been described. This suggested that metallurgical soils had an effect on the structure of plant communities independently from metal bioavailability. These overall results show that beside soil analyses, plants can provide additional indications regarding both the effects and potential mobility of pollutants.Il est aujourd'hui important de disposer d'outils efficaces pour évaluer la biodisponibilité et les effets écologiques des éléments métalliques des sols pollués. Dans ce contexte, la caractérisation de bioindicateurs de la qualité des sols représente un enjeu important. Pour répondre à cet objectif, nous proposons d'étudier l'accumulation foliaire et les associations végétales de la flore spontanée. Trois sites contaminés ont été étudiés. Sur deux d'entre eux, les concentrations métalliques (Cr, Cu, Ni, Pb et Zn) mesurées dans les plantes sont comparables à celles de la végétation se développant en milieu naturel non contaminé. Pour le troisième, ces concentrations sont significativement supérieures. De plus, ces analyses ont permis de différencier clairement les sites au regard de la phytodisponibilité des métaux. L'étude botanique des sites contaminés indique que si la végétation paraît normale, avec beaucoup d'espèces communes, les quatre associations végétales identifiées sont néanmoins particulières, voire inédites pour trois d'entre elles. Cette observation suggère que le substrat, indépendamment de la mobilité des métaux, a un effet sur la structure des communautés végétales. L'ensemble de ces résultats montre que l'analyse classique de sol, peut être avantageusement complétée par des analyses de la végétation au regard de l'estimation de la biodisponibilité des éléments métalliques et de leurs effets