Influence of synthetic antioxidants on the oxidation stability of biodiesel produced from acid raw Jatropha curcas oil

In the present work,Jatropha curcas biodiesel was produced from a high free fatty acid raw oil (AV = 3536 mg KOH g(-1)) containing 76.5% w/w of unsaturated fatty acids. The production route consisted of a two-step method, using acid esterification, followed by conventional alkali methanolysis. Biodiesel was characterized in agreement with EN 14214:2014 and a study on the use of 4 synthetic antioxidants was conducted. The high free fatty acid content of the oil could be reduced to 0.8% w/w by add esterification. A good product quality was generally observed but the very low oxidation stability, corresponding to an induction period (IP) of 1.37 h, was the highest concern. Statistically significant predictive models, which related each antioxidant concentration with the IP, were obtained. Pyrogallol (PY) showed the best results, being estimated that the use of 204 ppm in biodiesel could increase its IP to the limit imposed by the quality standard (8 h). The following rank, in terms of effectiveness, was obtained: PY > propyl gallate (PG) > butylated hydroxytoluene (BHT) > tert-butyl hydroquinone (TBHQ). In agreement, the stabilization factors (F), considering the use of 204 ppm of antioxidant, were: 5.84 for PY, 4.06 for PG, 1.85 for BHT and 0.85 for TBHQ

Oxygen transmissibility of piggyback systems with conventional soft and silicone hydrogel contact lenses

To investigate the apparent oxygen transmissibility of various piggyback systems using conventional and silicone hydrogel soft contact lenses of different water content and permeability, rigid poly(methyl methacrylate), and rigid gas-permeable lenses of medium, high, and ultrahigh oxygen permeability. The aim of the study was to establish which material (rigid or hydrogel) is more representative of the resulting oxygen performance of piggyback systems. METHODS: The apparent oxygen transmissibility of 66 piggyback systems was measured with an electrochemical method. Eighteen of these combinations involved the use of silicone hydrogel contact lenses currently available. One hyperpermeable rigid gas-permeable contact lens (tisilfocon A) was also included in the study. RESULTS: Measured apparent transmissibility correlates with rigid lens permeability (r = 0.403; SE = +/-3.03 barrer/cm; P < 0.001) and hydrogel lens permeability (r = 0.334; SE = +/-3.2 barrer/cm; P < 0.001). As expected, a linear model comprising permeability values from both rigid and soft materials gave a more precise estimation of the piggyback transmissibility (r = 0.736; SE = +/-2.02 barrer/cm; P < 0.001). The highest values of apparent oxygen transmissibility were found for the combination of tisilfocon A rigid material with any of the 3 silicone hydrogel lenses. Tisilfocon A material significantly improved the transmissibility of all piggyback systems even when conventional hydrogels are involved. CONCLUSION: The combination of hypertransmissible rigid gas permeable lenses with silicone hydrogel soft materials should result in normal corneal function under daily wear conditions. When fitting piggyback systems, clinicians must be aware of material selection to optimize oxygen performance. This is of particular importance in already compromised corneas.This study was supported in part by a grant from the Science and Technology Foundation (FCT), Ministry of Science and Superior Education (MCES), under contract 8281/2002 from the European Social Funding granted to J.M.G.-

Laboratory study on the behaviour of spent AA household alkaline batteries in incineration

The quantitative evaluation of emissions from incineration is essential when Life Cycle Assessment (LCA) studies consider this process as an end-of-life solution for some wastes. Thus, the objective of this work is to quantify the main gaseous emissions produced when spent AA alkaline batteries are incinerated. With this aim, batteries were kept for 1 h at 1273 K in a refractory steel tube hold in a horizontal electric furnace with temperature control. At one end of the refractory steel tube, a constant air flow input assures the presence of oxygen in the atmosphere and guides the gaseous emissions to a filter system followed by a set of two bubbler flasks having an aqueous solution of 10% (v/v) nitric acid. After each set of experiments, sulphur, chlorides and metals (As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Sb, Tl and Zn) were analyzed in both the solutions obtained from the steel tube washing and from the bubblers. Sulphur, chlorides and metals were quantified, respectively, using barium sulfate gravimetry, the Volhard method and atomic absorption spectrometry (AAS). The emissions of zinc, the most emitted metal, represent about 6.5% of the zinc content in the batteries. Emissions of manganese (whose oxide is the main component of the cathode) and iron (from the cathode collector) are negligible when compared with their amount in AA alkaline batteries. Mercury is the metal with higher volatility in the composition of the batteries and was collected even in the second bubbler flask. The amount of chlorides collected corresponds to about 36% of the chlorine in the battery sleeve that is made from PVC. A considerable part of the HCl formed in PVC plastic sleeve incineration is neutralized with KOH, zinc and manganese oxides and, thus, it is not totally released in the gas. Some of the emissions are predictable through a thermodynamic data analysis at temperatures in the range of 1200–1300 K taking into account the composition of the batteries. This analysis was done for most of potential reactions between components in the batteries as well as between them and the surrounding atmosphere and it reasonably agrees the experimental results. The results obtained show the role of alkaline batteries at the acid gases cleaning process, through the neutralization reactions of some of their components. Therefore, LCA of spent AA alkaline batteries at the municipal solid waste (MSW) incineration process must consider this contribution

Aluminum recovery from water treatment sludges

Aluminum sulfate and polyaluminum chloride are widely used as coagulants in water treatment plants. A chemical sludge containing aluminium hydroxide, adsorbed organic matter and other water insoluble impurities is obtained after the flocculation-clarification process. In Portugal, an estimated amount of 66 000 ton/yr. (wet wt.) water treatment sludge is being disposed of on land or at municipal solid waste (MSW) landfills. Government restrictions to this practice as well as increasing deposition costs and the potential harmful impacts proceeding from the high aluminium content of the sludge have been leading to significant research efforts in order to evaluate different treatment alternatives, namely involving aluminium recovery and subsequent reuse. Despite membrane-based separation and liquid ion ex-change processes have been studied for that purpose, the traditional acidic and alkaline extraction methods may be still explored to obtain a product susceptible of use as coagulant for industrial waste-water treatment purposes. Centrifuged chemical sludge from a water treatment plant using polyaluminium chloride as coagulant was characterised in terms of humidity, volatile matter, Al, Fe, Mn, Cd, Cu, Cr, Pb, Ni and Zn. The dry sludge organic content is about 29% and the major elements determined are aluminium (~ 12.6%), iron (~ 2%) and manganese (~ 0.14%). The aluminium recovery was investigated both by acidic and alkaline leaching processes. Concentrated H2SO4 was selected as the acidic leaching medium and the process efficiency was evaluated at different operating conditions. The ratio dry sludge/sulphuric acid solution was varied between 0.5 and 2%, the pH ranged from 1.0 to 4.5, different stirring and settling times were established and the aluminium, iron and manganese dissolution was assessed. A similar study was performed at pH values between 10.0 and 13.6 using 2N/10N NaOH as the extracting solution and operating conditions as those of the acid extraction procedure. Whereas maximum alu-minium recovery using H2SO4 was about 61% at pH=1.0, the alkaline extraction led to aluminium recoveries of about 71% at pH = 13.6 (2% dry sludge in suspension, 90 min stirring time and 45 min settling time). Decreasing the sludge dosage to 0.5%, aluminium extraction increased to 87.4% at pH=13. As expected, acid extraction led to a higher Fe (18.2%) and Mn (42.1%) dissolution as com-pared with alkaline extraction at pH=13.6 (Fe=2.1% and Mn=3.2%)

Characteristics of effluents from healthcare waste treatment with alkaline hydrolysis

Although alkaline hydrolysis emerges as an alternative process to treat healthcare waste (HCW), information about its emissions is scarce, namely as regards effluents production. This work aims to characterize the effluents from alkaline hydrolysis tests with samples of components usually present in HCW, under a temperature of 110 degrees C and with 1 M NaOH aqueous solutions. Some of the regulatory parameters for discharging effluents were determined; also, tests for assessing aerobic and anaerobic biodegradation of those effluents were carried out. The effluents showed values lower than threshold values for almost all the parameters except pH, total nitrogen, TOC, COD and BOD5. Although with high organic load, the effluents from discarded medical components (DMC) and animal tissues (AT) showed a percentage of aerobic biodegradation of 50.5 and 52.9%, respectively. The anaerobic biodegradability obtained for the effluents from DMC were 22.3 and 42.2% for those with AT

Inactivation of Geobacillus stearothermophilus spores by alkaline hydrolysis applied to medical waste treatment

Although alkaline hydrolysis treatment emerges as an alternative disinfection/sterilization method for medical waste, information on its effects on the inactivation of biological indicators is scarce. The effects of alkaline treatment on the resistance of Geobacillus stearothermophilus spores were investigated and the influence of temperature (80 degrees C, 100 degrees C and 110 degrees C) and NaOH concentration was evaluated. In addition, spore inactivation in the presence of animal tissues and discarded medical components, used as surrogate of medical waste, was also assessed. The effectiveness of the alkaline treatment was carried out by determination of survival curves and D-values. No significant differences were seen in D-values obtained at 80 degrees C and 100 degrees C for NaOH concentrations of 0.5 M and 0.75 M. The D-values obtained at 110 degrees C (2.3-0.5 min) were approximately 3 times lower than those at 100 degrees C (8.8-1.6 min). Independent of the presence of animal tissues and discarded medical components, 6 log10 reduction times varied between 66 and 5 min at 100 degrees C-0.1 M NaOH and 110 degrees C-1 M NaOH, respectively. The alkaline treatment may be used in future as a disinfection or sterilization alternative method for contaminated waste

Creative Little Scientists: enabling creativity through science and mathematics in preschool and first years of primary education: guidelines and curricula for teacher training (D5.2)

One of the key objectives of the Creative Little Scientists project is to propose a set of curriculum design principles as guidelines for European initial teacher education (ITE) and continuous professional development (CPD) programmes that will foster creative approaches to science and mathematics learning in preschool and the first years of primary education in the frame of inquiry-based educational environments. Work Package 5 is based on the findings of the theoretical review (Work Package 2), comparative studies (Work Package 3), and in-depth field research (Work Package 4). In addition it has been informed by the involvement of communities of stakeholders – teachers, student teachers, school staff members, teacher educators, researchers, out-of-the box thinkers, policy makers and experts in the field of inquiry, creativity or science – in online and face-to-face focus groups. This document offers teacher education policy makers and institutions a set of curriculum design principles and accompanying conceptual recommendations in order to design and apply curricula that will foster creative approaches to science and mathematics learning in preschool and first years of primary education. Furthermore it offers teacher education institutions a related set of teacher outcomes about what teachers should know and be able to do in order to develop such creative approaches. These can be seen as concrete recommendations for teacher educators and teacher education institutions to frame their sessions, workshops and courses. They are directly linked to the implications for teacher training which arose from deliverables D2.2 Conceptual Framework, D3.2 Report on Mapping and Comparing Recorded Practices, D3.3 Report on First Survey of School Practice and D4.4 Report on Practices and their Implications (see also Figure below)

Creative Little Scientists: enabling creativity through science and mathematics in preschool and first years of primary education: exemplary teacher training materials (D5.3)

This report focuses on the Exemplary Teacher Training Materials. The aim of these materials is to illustrate the teacher education Curriculum Design Principles and related Teacher Outcomes, which were developed during Work Package 5 as part of D5.2 Guidelines and Curricula for Teacher Training and can also be found in this report. They are designed for teacher educators to use in Initial Teacher Education (ITE) and teacher Continuing Professional Development (CPD). They aim to extend professional understanding and enhance professional development in order to foster creativity in science and mathematics education in the early years. This report explains the methodology used to develop the materials, the nature and structure of the materials and includes suggestions for their use in all phases of teacher education. Methodology used to develop the exemplary teacher training materials In the Creative Little Scientists project, the comparative research and the in-depth fieldwork in particular identified significant issues that need to be tackled in teacher education in order to foster creativity in science and mathematics education in the early years. Based on these issues the teacher education Content Design Principles, created during the curriculum design research, were refined, and a set of Teacher Outcomes developed. To produce the Exemplary Teacher Training Materials, classroom examples of creative learning and teaching were selected using these Content Design Principles and related Teacher Outcomes. All partners re-visited their data from the in-depth fieldwork (Work Package 4) to select pertinent images, interviews or classroom extracts that evidenced one or more of the Teacher Outcomes. To support and record the selection process a grid was provided where partners could record links between the fieldwork data selected, Teacher Outcomes and factors associated with creativity in learning and teaching in science and mathematics. Templates were then used to structure the classroom materials and provide consistent information about the contexts from which they were drawn. Teacher training materials: an overview and how to use them In total 169 templates are available containing exemplary materials from fieldwork for use in teacher education. These are structured in an Excel-file and can be found on the website http://www.creative-little-scientists.eu. In order to support the full use of this diverse range of resources for teacher training, suggestions are provided in this report of selection and use of these exemplary materials in relation to particular themes and associated Content Design Principles as follows: o Suggestion 1: Use of questions and ideas of children by teachers (Principles 10 and 11) o Suggestion 2: Resources and learning environment as essential context factors for Creativity and Inquiry (Principles 10, 14, 17) o Suggestion 3: Focus on the nature of science – a link with creativity (Principle 3) o Suggestion 4: Focus on Inquiry Based Science Education – link with creativity (Principle 6) o Suggestion 5: Focus on Practical Investigations which foster creativity (Principles 2, 17) o Suggestion 6: Collaboration/group work in inquiry and creativity based approaches (Principle 15) o Suggestion 7: The role of play in inquiry and creativity based approaches (Principles 7, 8, 17) o Suggestion 8: The use of the various modes of expression and representation of science and mathematics learning to support inquiry and the development of creativity – link with assessment (Principles 7, 9) o Suggestion 9: The role of the teacher in Inquiry and Creativity approaches (Principles 1, 7, 11) o Suggestion 10: Cross curricular project work to foster inquiry and creativity (Principle 6) The suggestions above are carefully chosen since they encourage inquiry and creativity in science and mathematics education for early years, by focusing on the synergies between Inquiry-Based Science Education (IBSE) and Creative Approaches (CA): play and exploration; motivation and affect; dialogue and collaboration; problem solving and agency; questioning and curiosity; reflection and reasoning; teacher scaffolding and involvement; and assessment for learning. As noted in the Conceptual Framework (D2.2) and experienced during the in-depth fieldwork, developing contexts for inquiry and exploration which foster creative learning, and achieving a balance between teacher intervention and children collaboration, as well as teacher standing back and learner agency, represent considerable professional challenges. The provided exemplary teacher training materials and associated suggestions for their use help address these challenges

Efeitos antidiabéticos de plantas medicinais do género Salvia

Apresentação efectuada no 6º Congresso Português de Diabetes, no Porto, em 2004.Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/12527/2003, SFRH/BD/6942/2001

Advanced and clean technologies for chromium tanned leather waste recycling and green energy production

Chromium tanned leather wastes are difficult to valorise by chemical and biological processes dueto the strong bonds established between collagen and chromium. Thus a one-step fast clean pressureassisted alkaline hydrolysis method has been studied to disrupt recalcitrant bonds. The effects of calciumoxide, temperature, time, liquid to solid ratio and leather scrap size on organic matrix destruction, chromiumdissolution and anaerobic biodegradability of hydrolyzates obtained were evaluated. The results show thatpressure-assisted hydrolysis with CaO may be a good alternative to reduce leather waste volume, obtainbiodegradable solutions with low Cr concentration and final residues usable as a chromium bearingresource. In the optimised conditions, about 50% to 55% of the leather is dissolved. The slurries obtainedcontain above 90% of the chromium. The hydrolyzates show good anaerobic biodegradability mostly in therange of 50% to 70 %, indicating them as a source of biogas