The effect of slurry conditioning on bitumen recovery and bitumen froth quality has been studied by using three oil sands ores tested with a laboratory hydrotransport extraction system (LHES) and a Denver flotation cell. Tests with the LHES show that an increase in slurry conditioning time yielded a lowered bitumen recovery for a long flotation time (30 min). Longer slurry conditioning time led to a better bitumen froth quality regardless of flotation time. However the over conditioning could be compensated by higher conditioning temperatures and higher slurry flow velocities. Tests with the Denver flotation cell show that the increase in slurry conditioning time resulted in a higher bitumen recovery and a better bitumen froth quality for both good and poor processing ores for a shorter flotation time of 5 min. For a longer flotation time of 20 min, increasing slurry conditioning time had little impact on bitumen recovery but led to a slightly better bitumen froth quality for the good processing ore whereas no effect on bitumen froth quality of the poor processing ore. Results also show that higher slurry temperatures and stronger mechanical energy input were beneficial to both bitumen recovery and bitumen froth quality for all three oil sands ores tested on both devices. / Chemical Engineering

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The conditioning effect in metabolomic studies is the phenomenon of initial variation of analytical results in the first 5-10 injections of a biological sample in chromatographic systems. The deviation manifests itself as a drift in retention time, peak area and in multivariate analysis. It is a major quality assurance problem in the metabolomic field and if not accounted for would result in high analytical variance. The aim of this study was to investigate the conditioning effect and to gain further knowledge about it. The study was carried out on UPLC of hydrophilic liquid chromatography (HILIC) type coupled to quadrupole time of flight (QTOF) MS. A systematic study was designed to investigate the effects of the age of the analytical column. An investigation into certain matrix components as a possible cause of the conditioning effect was made. Different sample preparation methods were investigated. One result showed that no conditioning could be seen and the system appeared stable from the first injection. Differences in sample composition between samples with conditioning effect and samples without conditioning effect were investigated. No correlation between conditioning effect and levels of certain matrix compounds could be found. More studies of correlation between sample composition and the amount of conditioning occurring is needed. Some samples appear to have no retention time drift but have a significant drift in peak area and in multivariate analysis. This is an indication that the conditioning effect should be analysed in more ways than one before determining if a system is stable.

Professional respondents in research panels: comparing trained and fresh members of an online panel The diploma thesis deals with the topic of changes in responding of research panel members, which are caused by their previous experience with research process. Various manifestations of this phenomenon, often labelled as the "panel conditioning effect", are described and supported by corresponding empirical evidence. The observations of panel conditioning effect come from longitudinal panel design as well as online access panels. The author proposes logically structured differentiation of the effect. Based on this categorization, several hypotheses about the differences between trained and fresh members of an Internet panel are raised and tested in dedicated online research. The results reveal significant differences between recently-registered and long-term members of the panel, both in their response strategies and in demographic structure of the groups. Yet the overall outcome do not indicate, that interviewing trained respondents would necessarily lead to lower-quality data.