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The Technology and Economy of Farm-Scale, High-Solids Anaerobic Digestion of Plant Biomass

Anaerobic digestion is a microbially mediated process occurring in nature in the absence of oxygen and other non-carbonaceous electron acceptors. The majority of the carbon of the organic matter degraded in the process is transformed into carbon dioxide and methane. Most of the energy potential of the degraded material is conserved in the methane, thus providing a renewable energy carrier, which c

The evolution of photosynthesis and its environmental impact

Photosynthesis in plants is a very complicated process, utilizing two photosystems in series to carry out the very energy-demanding process of oxidizing water to molecular oxygen and reducing carbon dioxide to organic compounds. The first photosynthetic organisms, living more than 3.4, perhaps even 3.8 Ga, i.e. American billion (109) years ago, carried out a simpler process, without oxygen product

Turbocharging to extend HCCI Operating Range in a Multi Cylinder Engine- Benefits and Limitations

In the last decade there has been interest in Homogenous Charge Compression Ignition- HCCI as a way to increase the efficiency of the gasoline engine. The attractive properties are increased fuel efficiency due to reduced throttling losses, increased expansion ratio and higher thermodynamic efficiency. The main drawback of HCCI is the absence of direct combustion timing control. Therefore all the

Blandade känslor: fruktan och förtröstan förr och nu

Mixed feelings: fear and consolation now and then (from the 17th to the 21st century). In Early Modern Swedish society a great amount of ideas, words and images were available to explain the earthly suffering. In the Lutheran practice of preaching, consolation, besides instruction and admonition, played an important role. Today, our life is not as hard as our ancestors’ was. This has enabled us to

CO2-free power generation - A study of three conceptually different plant layouts

Ever since the release of the Kyoto protocol the demand for CO2-free processes have been increasing. In this paper three different concepts with no or a very small release of CO2 to the atmosphere are evaluated and compared concerning plant efficiency and investment cost. A novel approach to biomass gasification is proposed to provide fuel for a combined gas turbine cycle, where the biomass is con

Saudi Arabia

Comparable country profile that describes the evolution and practice of corporate Sustainability and Responsibility (CSR) in Saudi Arabia.

Design, Modelling and Control of Electrical Machines - With Applications to Iron-powder Machines and Acoustic Noise

Popular Abstract in Swedish Avhandlingen består av två delar, den första som behandlar konstruktionen av järn-pulver maskiner, och den andra med analys av ljud från el-maskiner. I Del I, en elektrisk magnetiserad klo-pol synkron maskin på 1.6 kW har byggts. Maskinen är byggt från mjuk magnetisk material (SMC), också kallad järn-pulver. Detta materialet har isotropiska magnetiska egenskaper, som gThis thesis consists of two parts, the first dealing with the design of iron-powder synchronous machines, and the second with the analysis and prediction of the acoustic noise in electrical machines. In Part I, a 1.6 kW electrically magnetized claw-pole machine with magnetically conducting end-plates has been analyzed and a prototype tested. The machine is built from soft magnetic composite mater