Biofuels in Spain: Market penetration analysis and competitiveness in the automotive fuel market

For several years the European Union (E.U.) has been promoting the use of biofuels due to their potential benefits such as the reduction of dependence on foreign energy imports (the raw materials can be produced within the E.U.), the more stable fossil fuel prices (they can replace fossil fuels on the market), the greenhouse gas (GHG) reduction (biofuels’ raw materials fix CO₂ from the atmosphere) and the fact that they can represent an additional source of income for the primary sector (biofuels’ raw materials are vegetables that can be grown and harvested).Despite the public aids (direct and indirect), biofuels are not competitive with fossil fuels at present, but it is possible that in the future the environment conditions change and biofuels might become competitive. It is difficult to assess whether this will happen or not, but it is possible to make an assessment of a future situation.This article presents two analyses with one objective: to determine if biofuels might become competitive in the future. The first analysis examines the dependencies of two quotations which have a strong relationship with fuels: the crude oil quotation and the CO₂ bond quotation. The analysis of these relationships may help to forecast the future competitiveness of biofuels. For instance, biofuels’ future competitiveness will be higher if their raw material costs are not related to crude oil quotations or if they are related in a negative way (the higher the crude oil quotations the lower the raw material biofuels’ cost). The second analysis focuses on the market penetration of biofuels in the Spanish market. There are data related to biofuels monthly consumption in Spain since 2007 and it is possible to know if biofuels are gaining market quota since then.     

Development of a computer-assisted system to teach pathologic anatomy. Preliminary results

BACKGROUND: The present study describes the implantation of an interactive teaching system to improve both the active involvement of the student and the learning quality of Pathology. The preliminary results from the evaluation of such system are also reported. METHODS: Two attitude questionnaires (rating scale) were passed to a sample of 36 students of Medicine, randomly elected. These students used for 10 weeks a programme of Pathology (Interpat) assisted by computer. Moreover, the data stored after each session by the control stack of this programme are analyzed. RESULTS: The programme is positively evaluated by the users who consider it as an appropriate mode of learning Pathology. In spite of the scarce experience with computers, students have no difficulty in using this programme. 82% of students consider that they learn more Pathology with Interpat than with the traditional system of magistral classes. 63% of students believe that similar systems must be applied in other curricula. The average time of use of the system by each student has been 11 h 45 min (SD 4 h 55 min). The videodisc is the stack more used. CONCLUSIONS: There is a good acceptance of this methodology by the students, being almost no difficulty in using the programme, despite their low level of computer knowledge. The program is a potent instrument for individualizing the teaching of Pathology. The small size of the sample, accurate for a preliminary study as this is, must be take into account when generalizing the results.     

Study of ash deposition during coal combustion under oxyfuel conditions

This paper presents a comparative study on ash deposition of two selected coals, Russian coal and lignite, under oxyfuel (O₂/CO₂) and air combustion conditions. The comparison is based on experimental results and subsequent evaluation of the data and observed trends. Deposited as well as remaining filter ash (fine ash) samples were subjected to XRD and ICP analyses in order to study the chemical composition and mineral transformations undergone in the ash under the combustion conditions. The experimental results show higher deposition propensities under oxyfuel conditions; the possible reasons for this are investigated by analyzing the parameters affecting the ash deposition phenomena. Particle size seems to be larger for the Russian coal oxy-fired ash, leading to increased impaction on the deposition surfaces. The chemical and mineralogical compositions do not seem to differ significantly between air and oxyfuel conditions.The differences in the physical properties of the flue gas between air combustion and oxyfuel combustion, e.g. density, viscosity, molar heat capacity, lead to changes in the flow field (velocities, particle trajectory and temperature) that together with the ash particle size shift seem to play a role in the observed ash deposition phenomena.     

Critical analysis on hydrogen as an alternative to fossil fuels and biofuels for vehicles in Europe

In recent times, the global debate on the environment has been centered on CO₂ emissions. This gas is the major cause of the “greenhouse effect” and people are more concerned with the idea that the emissions of this gas should be minimized. As a result of this concern, the Kyoto Protocol was enacted and subscribed to by many countries, setting the maximum gas emissions for them.Fossil fuels are a major source of CO₂ emissions. For some years now The European Union has been seeking to promote some years now the use of biofuels as substitutes for diesel or petrol for transport purposes. As a result of this policy, in 2003 the European Union (EU) Directive 2003/30/EC [1] was developed with the aim of promoting the use of biofuels as a substitute for diesel or gasoline among European Union countries as well as to contribute to fulfilling the commitments acquired on climate change, security of supply in environmentally friendly conditions and the promotion of renewable energy sources.In order to achieve these goals, the directive forces all EU members to ensure that before December 31 of 2010 at least 5.75% of all gasoline and diesel fuels sold for transport purposes are biofuels. European Union countries have social and economic characteristics unique to themselves. The energy dependence on foreign sources, the features of the agricultural sector or the degree of industrialization varies greatly from one country to another. In this context, it is questionable whether the obligation imposed by this directive is actually achieving in its application uniform and/or identical goals in each of the countries involved and whether the actions of the various governments are also aligned with these goals. All these ideas were developed in a previous report (Sobrino and Monroy (2009) [2]).This report examines the possibility of using hydrogen as an alternative to fossil fuels and biofuels from a technical, economic and environmental point of view in the specific case of a European Union country: Spain.     

Dispersion of graphite flakes into boehmite sols for the preparation of bi-layer-graphene / alumina coatings on stainless steel for tribological applications

Carbon-alumina coatings on stainless steel were prepared by a sol-gel route. The dispersion of the commercial graphite flakes by an ultrasonic bath, an ultrasonic probe and a high-shear mixer, produce thinner flakes, few-layered-graphene and bi-layer-graphene (BLG), respectively. The coatings were examined by optical and electron microscopy, interferential rugosimetry, optical profilometry and Raman spectroscopy. The friction coefficient against a steel ball is decreased by a factor of 5–7 and the wear volume is reduced by a factor of 6–38 compared to a pure alumina coating. The best results correspond to the sample prepared using the high-shear mixer. Delamination of the graphite flakes into BLG during the friction test provides the system with debris suitable for tribofilm building up and lubrication but it is better to already have carbon dispersed as BLG in the coating before the test, notably because the carbon surface area available is much higher.     

Land surface temperature retrieval from LANDSAT TM 5

In this paper, three methods to retrieve the land surface temperature (LST) from thermal infrared data supplied by band 6 of the Thematic Mapper (TM) sensor onboard the Landsat 5 satellite are compared. The first of them lies on the estimation of the land surface temperature from the radiative transfer equation using in situ radiosounding data. The others two are the mono-window algorithm developed by Qin et al. [International Journal of Remote Sensing 22 (2001) 3719] and the single-channel algorithm developed by Jiménez-Muñoz and Sobrino [Journal of Geophysical Research 108 (2003)]. The land surface emissivity (LSE) values needed in order to apply these methods have been estimated from a methodology that uses the visible and near infrared bands. Finally, we present a comparison between the LST measured in situ and the retrieved by the algorithms over an agricultural region of Spain (La Plana de Requena-Utiel). The results show a root mean square deviation (rmsd) of 0.009 for emissivity and lower than 1 K for land surface temperature when the Jiménez-Muñoz algorithm is used.