Sökning: "oxygen"
Visar resultat 6 - 10 av 2641 avhandlingar innehållade ordet oxygen.
6. Optimization of Pretreatment of Kraft Pulp with Nitrogen Oxides
Sammanfattning : Modified kraft pulp subjected to oxygen bleaching following pretreatment with 2% nitrogen dioxide for 140 min with the addition of oxygen resulted in low selectivity after subsequent oxygen bleaching. In contrast, pretreatment in the absence of oxygen removed more than 80% of the lignin after oxygen bleaching and still maintained high selectivity (kappa number less than 5 at viscosity 950 dm3/kg). LÄS MER
7. Design and Operation of a 10 kWth Chemical-Looping Combustor for Solid Fuels
Sammanfattning : Chemical-looping combustion (CLC) is a new fuel conversion technology with inherent CO2 capture. In this process, the fuel and the combustion air are never mixed and the oxygen is transferred to the fuel via an oxygen carrier in the form of a metal oxide circulating between two reactors, e.g. LÄS MER
8. Oxygen Vacancy Chemistry in Ceria
Sammanfattning : Cerium(IV) oxide (CeO2), ceria, is an active metal oxide used in solid oxide fuel cells and for the purification of exhaust gases in vehicle emissions control. Behind these technically important applications of ceria lies one overriding feature, namely ceria's exceptional reduction-oxidation properties. LÄS MER
9. Steel converter slag as an oxygen carrier
Sammanfattning : Thermal conversion of fuels can be used to produce heat and power in addition to chemicals. In order to be aligned with climate targets, it is necessary that such systems do not emit carbon dioxide to the atmosphere. Carbon capture and storage (CCS) can be used together with fuel conversion systems to prevent CO2 from entering the atmosphere. LÄS MER
10. Internal oxygen transport to below-ground parts: importance for emergent macrophytes
Sammanfattning : This thesis examines factors regulating growth and distribution of emergent plants with focus on effects of oxygen supply to the roots. Greenhouse experiments revealed that P. australis acclimatizes to specific water depths with phenotypic plasticity. LÄS MER