Development of processes for the production of solar grade silicon from halides and alkali metals, phase 1 and phase 2

High temperature reactions of silicon halides with alkali metals for the production of solar grade silicon are described. Product separation and collection processes were evaluated, measure heat release parameters for scaling purposes and effects of reactants and/or products on materials of reactor construction were determined, and preliminary engineering and economic analysis of a scaled up process were made. The feasibility of the basic process to make and collect silicon was demonstrated. The jet impaction/separation process was demonstrated to be a purification process. The rate at which gas phase species from silicon particle precursors, the time required for silane decomposition to produce particles, and the competing rate of growth of silicon seed particles injected into a decomposing silane environment were determined. The extent of silane decomposition as a function of residence time, temperature, and pressure was measured by infrared absorption spectroscopy. A simplistic model is presented to explain the growth of silicon in a decomposing silane enviroment

Quality related communication approaches for organic food

As food quality becomes more complex, consumer s are tending to reduce their involvement in the food purchase decision- making process. Consequently, prices are becoming more significant as they represent an easy choice criterion when consumer s have less information about the differences between the product and process quality inherent in food items (including environmental or social issues). The organic food sector provides high, complex food quality profiles and has therefore been seriously affected by this development. Consequently some SMEs in the food business sector are starting to emphasize certain quality factors, such as sustainable production and processing, as a means of communicating their added value to consumer s. Based on published scientific and unpublished literature, this paper provides an overview of the main instrument s and media of communication on food quality, illustrated by case studies. It also present s the results of a test by means of an information display matrix, conducted in order to analyse the consumer information and quality assessment behaviour involved in apple purchase in Switzerland. Keywords food quality, food indicators, means of communication, food miles, social standards, consumer behaviour.Marketing,

The development of an advanced system to cool a man in a pressure suit

Conductive cooling system for cooling man in pressurized space sui

The Challenge of Preparing and Testing Combinatorial Compound Libraries in the Fast Lane, at the Front End of Drug Development

Combinatorial Compound Libraries (CCL) are at the front end of the development of new chemical entities. They are the result of a pragmatic, goal-oriented attitude, which emphasizes the discovery side of research activities. The odds to bump into a discovery, however, are pushed to the extreme with rigorously planned rationales. The CCL field has its origin in peptide chemistry but is migrating into general organic chemistry. The incentive is the coveted goal to be able to prepare large libraries of 'small molecules'. Efforts are directed towards an expansion of the repertoire of high yield reactions on solid phase, in order to readily access semi-rigid globular ligands. The CCL approach comes with its own strategies to provide a massive increase of compound evaluations by taking full advantage of the integrated preparation process with the option to control the physical format of compound ensembles or to classify them into defined subpopulations. A noticeable impact on the drug discovery process is expected. The libraries' preparation and evaluation principles are briefly discussed in this essay

Considering sensing-intuitive dimension to exposition-exemplification in adaptive sequencing

Proceedings of the Second International Conference, AH 2002 Málaga, SpainThe final publication is available at Springer via http://dx.doi.org/10.1007/3-540-47952-X_83This paper shows a way of using sensing-intuitive dimension of learning styles of students in order to improve the efficiency of adaptive learning systems. Firstly, it introduces the procedure of extracting information about sensing-intuitive students from the Felder-Soloman ILS questionnaire. Then, it presents a mechanism of application of sensing-intuitive dimension to exposition-exemplification sequencing. The example used to explain the adaptation effects is taken from a chess course developed with TANGOW, Task-based Adaptive learNer Guidance On the Web.The Spanish Interdepartmental Commission of Science and Technology (CICYT) has sponsored this paper, project number TEL1999-0181 and project number TIC2001-0685-C02-01

Equation of state and Beginning of Thermalization After Preheating

We study the out-of-equilibrium nonlinear dynamics of fields after post-inflationary preheating. During preheating, the energy in the homogeneous inflaton is exponentially rapidly transfered into highly occupied out-of-equilibrium inhomogeneous modes, which subsequently evolve towards equilibrium. The infrared modes excited during preheating evolve towards a saturated distribution long before thermalization completes. We compute the equation of state during and immediately after preheating. It rapidly evolves towards radiation domination long before the actual thermal equilibrium is established. The exact time of this transition is a non-monotonic function of the coupling between the inflaton and the decay products, and it varies only very weakly (around 10^(-35) s) as this coupling changes over several orders of magnitude. This result is applied to refine the relation between the number of efoldings N and the physical wavelength of perturbations generated during inflation. We also discuss the implications for the theory of modulated perturbations from preheating. We finally argue that many questions of the thermal history of the universe should be addressed in terms of pre-thermalization, illustrating this point with a calculation of perturbative production of gravitinos immediately after chaotic inflation. We also highlight the effects of three-legs inflaton interactions on the dynamics of preheating and thermalization in an expanding universe.Comment: 15 pages, 13 figure

A Survey of Learning Styles of Engineering Students

This study examined the learning styles of engineering students using the Index of Learning Styles (ILS) developed by Soloman and Felder (Soloman & Felder, 2002), the Cognitive Styles Analysis (CSA) developed by Riding (Riding, 1991), and the Learning Style Inventory (LSI) developed by Kolb (Kolb, 1993). Thirty-five graduate and thirty-six undergraduate engineering students took each of the assessments. There was a strong preference for the visual category on the ILS, but an even split for the imagery/verbal dimension on the CSA. Scores were also evenly split on the active/reflective and sequential/global dimensions on the ILS. Another strong preference was seen for the analytic category on the CSA. On the LSI, most students' scores indicated a preference for the convergent category and no student scores were in the divergent category. An overview of each of the instruments as well as a summary of student learning needs for each of the dimensions is presented.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

A Process for Improving Course Quality based on Mid-Semester Feedback

Proceedings of: First International Conference on Reforming Education, Quality of Teaching and Technology-Enhanced Learning: Learning Technologies, Quality of Education, Educational Systems, Evaluation, Pedagogies (TECH-EDUCATION 2010). Athens, Greece, May 19-21, 2010.Quality control mechanisms are becoming more important in higher educational institutions. Student evaluation of teaching is typically used to obtain feedback from students about a learning experience but its effect in the course may take too long. Fast feedback mechanisms, in exchange, look at obtaining feedback in order to apply corrective measures quickly. In this paper a process is described to obtain feedback from the students about a course, analyze the received results, and identify the most significant aspects. The process has been applied to a course and led to some adjustments that had immediate impact on the course.The authors are truly indebted to Miguel Valero for his guidance during the design of this process. Work partially funded by the Learn3 project, “Plan Nacional de I+D+I TIN2008-05163/TSI”, the Best Practice Network ICOPER (Grant No. ECP-2007-EDU-417007), the Flexo Project “Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica” (Ref. TSI-020301-2008-19), and the “Emadrid: Investigación y desarrollo de tecnologías para el e-learning en la Comunidad de Madrid” project (S2009/TIC-1650).Publicad