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To produce fuel from gasified biomass is a way to manufacture carbon dioxide neutral fuels for transport purposes. The biomass is gasified by heat in a gasification unit, with or without nitrogen, and the resulting mixture consist of hydrogen, carbon dioxide, carbon monoxide, methane, steam, higher hydrocarbons in low concentration and tars. The gas will also contain nitrogen, argon, ammonia, hydr

Pay-What-You-Want (PWYW) pricing schemes are popular in certain industries and not others. We model the seller's choice of pricing scheme under various market structures assuming consumers share their surplus. We show that the profitability and popularity of PWYW depend not only on consumers' preferences, but also on market structure, product characteristics and sellers' strategies. While there is

Språkets speglingar är en hyllning till språket och den humanistiska traditionen. Den är tillägnad professor Birger Bergh som lämnade lärostolen i latin i juni 2000. 80 svenska och utländska forskare medverkar och ger tillsammans ett tvärsnitt av pågående forskning kring språket från studier över den kränkte Akilles vrede och synen på naturen i antiken till Selma Lagerlöfs högläsningskvällar och V

Ethanol from bio-products has become an important fuel for future power production. However, the present production technology is rather expensive. This paper focuses on how to lower the production cost of ethanol extraction from mash, and to use the ethanol as a primary fuel in gas turbines for heat and power production. Today, ethanol is produced during distillation by supplying energy to extrac

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The European Union has initiated a number of initiatives to improve resource efficiency in Europe. The Ecodesign Directive is one of the policy instruments that could aid the transition towards a more resource efficient economy. So far, the Directive has mainly been applied to set requirements related to energy efficiency, but there is potential for setting legal standards that increase product du

Popular Abstract in Swedish I följande arbete har ett dynamiskt modellbibliotek av komponenter utvecklats för processlinjer. Analysen inriktades mot karakteristiska aspekter för processlinjer för flytande livsmedel, och nya modeller utvecklades för byte av fluidum, dispersion, blandfaser och första ordningens kemiska reaktioner i rör och värmeväxlare. Modellernas beräkningseffektivitet och noggranIn the present work a dynamic model library of components for process lines was developed. The analysis addressed characteristic aspects of liquid food process lines, and new models were developed for fluid transitions, dispersion, mixing zones and first-order chemical reactions in pipes and heat exchangers. The computational efficiency and accuracy of the models were analysed. It was demonstrated

Modern adaptive techniques in two-point boundary value problems generate the mesh by constructing a function that maps a uniform grid to the desired nonuniform grid. This paper describes a new control algorithm for constructing a grid density function $phi(x)$, such that the local mesh width $Delta x_{j+1/2}=x_{j+1}-x_j$ is computed as $Delta x_{j+1/2} = varepsilon_N / varphi_{j+1/2}$. Here $varep