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Equalization and the offshore accords of 2005Metz, Ashley Corinne 16 October 2006
The ad hoc Offshore Accords signed between the Martin Government, and each Newfoundland and Nova Scotia have fundamentally altered the landscape of regional redistribution in Canada. The fallout from the Accords has had an immediate impact on the functioning of the Equalization Program and the political factors that inform debate over future reforms. This thesis examines the factors that led to the February 2005 Offshore Accords. It also examines the case of Saskatchewan's treatment under the Equalization Program
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Equalization and the offshore accords of 2005Metz, Ashley Corinne 16 October 2006 (has links)
The ad hoc Offshore Accords signed between the Martin Government, and each Newfoundland and Nova Scotia have fundamentally altered the landscape of regional redistribution in Canada. The fallout from the Accords has had an immediate impact on the functioning of the Equalization Program and the political factors that inform debate over future reforms. This thesis examines the factors that led to the February 2005 Offshore Accords. It also examines the case of Saskatchewan's treatment under the Equalization Program
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Μεταβολισμός της βιομηχανικής γλυκερόλης σε ελαιογόνους ζυγομύκητες και συσσώρευση αποθεματικών λιπιδίων υπό μη-ασηπτικές συνθήκεςΜουστόγιαννη, Άννα 27 April 2015 (has links)
Λόγω της αύξησης των τιμών του αργού πετρελαίου, τα τελευταία χρόνια η παραγωγή βιοντίζελ (biodiesel) έχει αποκτήσει μεγάλο ενδιαφέρον. Η χρήση των φυτικών ελαίων ως πρώτη ύλη στη βιομηχανία παραγωγής βιοντίζελ έχει πολλά μειονεκτήματα. Επομένως, το ενδιαφέρον των ερευνητών έχει στραφεί στη χρήση των SCO (ελαίων μονοκύτταρων οργανισμών), ως μία εναλλακτική πρώτη ύλη. Στην παρούσα διπλωματική εργασία, η βιομηχανική γλυκερόλη μετατράπηκε σε SCO από διάφορα στελέχη ελαιογόνων Ζυγομυκήτων, οι οποίοι καλλιεργήθηκαν υπό μη-ασηπτικές συνθήκες, χρησιμοποιώντας εκλεκτικά, περιοριστικά ως προς την πηγή αζώτου θρεπτικά μέσα καλλιέργειας, τα οποία ανέστειλαν τη βακτηριακή αύξηση.
Όταν οι μύκητες Thamnidium elegans, Mortierella ramanniana, Mortierella isabellina, Zygorhynchus moelleri, Mucor sp. και Cunninghamella echinulatα καλλιεργήθηκαν σε pH6 υπό μη-ασηπτικές συνθήκες, ήταν ικανοί να παράγουν 1,2- 4,1 g/l βιομάζα και να συνθέτουν 17,5- 49,3% wt/wt λιπίδια επί της ξηρής τους βιομάζας. Τα επίπεδα σύνθεσης της βιομάζας ήταν ~50% χαμηλότερα από εκείνα που επιτεύχθηκαν όταν οι Ζυγομύκητες καλλιεργήθηκαν υπό ασηπτικές συνθήκες. Διάφορες αντι-βακτηριακές ουσίες (αιθέρια έλαια, αντιβιοτικά) χρησιμοποιήθηκαν ώστε να επιτευχθεί υψηλότερη συσσώρευση βιομάζας και λιπιδίων από τους Ζυγομύκητες. Σε pH5, ο μύκητας M. ramanniana παρήγαγε 4,4 g/l βιομάζα που περιείχε 22% wt/wt λιπίδια, ενώ ο μύκητας T. elegans παρήγαγε 3,4 g/l βιομάζα που περιείχε 45% wt/wt λιπίδια επί της ξηρής τους βιομάζας. Όταν προστέθηκε στο μέσο καλλιέργειας αιθέριο έλαιο θυμαριού, 4,8 g/l βιομάζα συντέθηκαν από το μύκητα Τ. elegans που περιείχαν 42,6% wt/wt λιπίδια. Επιπλέον, όταν προστέθηκαν στο μέσο καλλιέργειας αντιβιοτικά και αιθέριο έλαιο, ο μύκητας T. elegans ήταν ικανός να παράγει 7,9 g/l βιομάζα που περιείχε 31,5 % wt/wt λιπίδια.
Τα αποτελέσματα έδειξαν ότι αν και ο πληθυσμός των βακτηρίων ανέστειλε την αύξηση των μυκήτων, η συσσώρευση των λιπιδίων δεν επηρεάστηκε από την παρουσία των βακτηρίων στο μέσο καλλιέργειας, συγκρινόμενα με αποτελέσματα πειραμάτων που πραγματοποιήθηκαν υπό ασηπτικές συνθήκες (control). Ως εκ τούτου, αναπτύχθηκε μια διεργασία δύο σταδίων στις κωνικές φιάλες και στο βιοαντιδραστήρα, κατά την οποία η αύξηση του μύκητα πραγματοποιήθηκε υπό ασηπτικές συνθήκες (1ο στάδιο) και ακολούθησε η συσσώρευση των λιπιδίων που πραγματοποιήθηκε υπό μη-ασηπτικές συνθήκες (2ο στάδιο). Στο 2ο στάδιο, προστέθηκε στο θρεπτικό μέσο καλλιέργειας αιθέριο έλαιο θυμαριού ως αντι- βακτηριακή ουσία. Από αυτή τη διεργασία, υψηλές ποσότητες λιπιδίων συσσωρεύτηκαν μέσα στο μυκήλιο του μύκητα, με απόδοση που έφτασε περίπου 13% wt/wt μικροβιακού ελαίου ανά καταναλωθείσα γλυκερόλη. / Biodiesel production has gained much interest during last years as an alternative fuel source, which arises from the escalating prices of petroleum fuels. The use of plant oils as feedstock for the biodiesel manufacture has many drawbacks, thus the interest has turned to single cell oil (SCO) as an alternative. In this thesis, raw glycerol was converted into SCO by oleaginous Zygomycetes, cultivated under non-aseptic conditions, using selective nitrogen limited media that inhibit the bacterial growth.
Thamnidium elegans, Mortierella ramanniana, Mortierella isabellina, Zygorhynchus moelleri, Mucor sp. and Cunninghamella echinulata, cultivated at pH6 under non-aseptic conditions, were able to produce 1.2- 4.1 g/l of biomass and synthesized 17.5- 49.3 % wt/wt of lipids in their biomass. These accumulation levels in biomass were ~50% lower compared to those achieved when Zygomycetes grown under aseptic conditions. Various anti-bacterial compounds, including essential oils and antibiotics were used in order to achieve a higher biomass and lipid accumulation. At pH5, M. ramanniana produced 4.4 g/l biomass containing 22% wt/wt lipids in their biomass, while T. elegans produced 3.4 g/l biomass containing 45% wt/wt of lipids. When thyme essential oil was added into the growth medium, T. elegans produced 4.8 g/l biomass containing 42.6% wt/wt lipids. Furthermore, with the addition of antibiotics together with essential oil into the medium, the production of SCO was further improved with T. elegans being able to produce 7.9 g/l of biomass containing 31.5% wt/wt lipids.
The obtained data showed that although bacterial populations inhibited the fungal growth, lipid accumulation remained unaffected by the presence of bacteria in the growth medium compared to control experiments (conducted under aseptic conditions). Therefore, a two-stage process was developed in both flasks and bioreactor, in which growth was performed under aseptic conditions (1st stage) followed by lipid accumulation performed under non-aseptic conditions (2nd stage) in the presence of thyme essential oil as an antibacterial agent. Large amounts of lipids were accumulated inside the mycelia, yielding around 13% wt/wt of oil per glycerol consumed.
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A Detailed Observational Analysis of V1324 Sco, the Most Gamma-Ray-luminous Classical Nova to DateFinzell, Thomas, Chomiuk, Laura, Metzger, Brian D., Walter, Frederick M., Linford, Justin D., Mukai, Koji, Nelson, Thomas, Weston, Jennifer H. S., Zheng, Yong, Sokoloski, Jennifer L., Mioduszewski, Amy, Rupen, Michael P., Dong, Subo, Starrfield, Sumner, Cheung, C. C., Woodward, Charles E., Taylor, Gregory B., Bohlsen, Terry, Buil, Christian, Prieto, Jose, Wagner, R. Mark, Bensby, Thomas, Bond, I. A., Sumi, T., Bennett, D. P., Abe, F., Koshimoto, N., Suzuki, D., Tristram, P. J., Christie, Grant W., Natusch, Tim, McCormick, Jennie, Yee, Jennifer, Gould, Andy 12 January 2018 (has links)
It has recently been discovered that some, if not all, classical novae emit GeV gamma-rays during outburst, but the mechanisms involved in the production ofgamma-rays are still not well understood. We present here a comprehensive multiwavelength data set-from radio to X-rays-for the most gamma-ray-luminous classical nova to date, V1324 Sco. Using this data set, we show that V1324 Sco is a canonical dusty Fe II-type nova, with a maximum ejecta velocity of 2600 km s(-1) and an ejecta mass of a few x 10(-5) M-circle dot. There is also evidence for complex shock interactions, including a double-peaked radio light curve which shows high brightness temperatures at early times. To explore why V1324. Sco was so gamma-ray luminous, we present a model of the nova ejecta featuring strong internal shocks and find that higher gamma-ray luminosities result from higher ejecta velocities and/or mass-loss rates. Comparison of V1324. Sco with other gamma-ray-detected novae does not show clear signatures of either, and we conclude that a larger sample of similarly well-observed novae is needed to understand the origin and variation of gamma-rays in novae.
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A Report on the X-ray Properties of the τ Sco Class of Stars.Ignace, Richard, Oskinova, L., Massa, D. 11 February 2013 (has links) (PDF)
An increasing number of OB stars have been shown to possess magnetic fields. Although the sample remains small, it is surprising that the magnetic and X-ray properties of these stars appear to be far less correlated than expected. This contradicts model predictions, which generally indicate that the X-rays from magnetic stars are harder and more luminous than their non-magnetic counterparts. Instead, the X-ray properties of magnetic OB stars are quite diverse. τ Sco is one example where the expectations are better met. This bright main-sequence, early B star has been studied extensively in a variety of wavebands. It has a surface magnetic field of around 500 G, and Zeeman Doppler tomography has revealed an unusual field configuration. Furthermore, τ Sco displays an unusually hard X-ray spectrum, much harder than similar, non-magnetic OB stars. In addition, the profiles of its UV P Cygni wind lines have long been known to possess a peculiar morphology. Recently, two stars, HD 66665 and HD 63425, whose spectral types and UV wind line profiles are similar to those of τ Sco, have also been determined to be magnetic. In the hope of establishing a magnetic field – X-ray connection for at least a subset of the magnetic stars, we obtained XMM–Newton European Photon Imaging Camera spectra of these two objects. Our results for HD 66665 are somewhat inconclusive. No especially strong hard component is detected; however, the number of source counts is insufficient to rule out hard emission. Longer exposure is needed to assess the nature of the X-rays from this star. On the other hand, we do find that HD 63425 has a substantial hard X-ray component, thereby bolstering its close similarity to τ Sco.
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Discovery of the first τ Sco Analogues: HD 66665 and HD 63425.Petit, V., Massa, D., Marcolinino, W., Wade, G., Ignace, Richard 01 March 2011 (has links) (PDF)
The B0.2 V magnetic star τ Sco stands out from the larger population of massive OB stars due to its high X-ray activity, peculiar wind diagnostics and highly complex magnetic field. This Letter presents the discovery of the first two τ Sco analogues – HD 66665 and HD 63425, identified by the striking similarity of their ultraviolet (UV) spectra to that of τ Sco. ESPaDOnS spectropolarimetric observations were secured by the Magnetism in Massive Stars CFHT Large Program, in order to characterize the stellar and magnetic properties of these stars. cmfgen modelling of optical ESPaDOnS spectra and archived IUE UV spectra showed that these stars have stellar parameters similar to those of τ Sco. A magnetic field of similar surface strength is found on both stars, reinforcing the connection between the presence of a magnetic field and wind peculiarities. However, additional phase-resolved observations will be required in order to assess the potential complexity of the magnetic fields and verify if the wind anomalies are linked to this property.
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A Multi-Phase Suzaku Study of τ Sco.Ignace, Richard, Oskinova, L., Jardine, M., Cassinelli, J., Cohen, D., Donati, J.-F., Townsend, R., ud-Doula, A. 01 October 2010 (has links) (PDF)
We obtained relatively high signal-to-noise X-ray spectral data of the early massive star τ Sco (B0.2V) with the Suzaku X-ray Imaging Spectrometer (XIS) instrument. This source displays several unusual features that motivated our study: (1) redshifted absorption in UV P Cygni lines to approximately +250 km s−1 suggestive of infalling gas, (2) unusually hard X-ray emission requiring hot plasma at temperatures in excess of 10 MK whereas most massive stars show relatively soft X-rays at a few MK, and (3) a complex photospheric magnetic field of open and closed field lines. In an attempt to understand the hard component better, X-ray data were obtained at six roughly equally spaced phases within the same epoch of τ Sco’s 41 day rotation period. The XIS instrument has three operable detectors: XIS1 is back-illuminated with sensitivity down to 0.2 keV; XIS0 and XIS2 are front-illuminated with sensitivity only down to 0.4 keV and have an overall less effective area than XIS1. The XIS0 and XIS3 detectors show relatively little variability. In contrast, there is a ≈4σ detection of a ≈4% drop in the count rate of the XIS1 detector at one rotational phase. In addition, all three detectors show a ≈3% increase in count rate at the same phase. The most optimistic prediction of X-ray variability allows for a 40% change in the count rate, particularly near phases where we have pointings. Observed modulations in the X-ray light curve on the rotation cycle is an order of magnitude smaller than this, which places new stringent constraints on future modeling of this interesting magnetic massive star.
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Progress on Noble Metal-Based Catalysts Dedicated to the Selective Catalytic Ammonia Oxidation into Nitrogen and Water Vapor (NH3-SCO)Jabło´nska, Magdalena 05 May 2023 (has links)
A recent development for selective ammonia oxidation into nitrogen and water vapor (NH3-SCO) over noble metal-based catalysts is covered in the mini-review. As ammonia (NH3) can harm human health and the environment, it led to stringent regulations by environmental agencies around the world. With the enforcement of the Euro VI emission standards, in which a limitation for NH3 emissions is proposed, NH3 emissions are becoming more and more of a concern. Noble metal-based catalysts (i.e., in the metallic form, noble metals supported on metal oxides or ion-exchanged zeolites, etc.) were rapidly found to possess high catalytic activity for NH3 oxidation at low temperatures. Thus, a comprehensive discussion of property-activity correlations of the noble-based catalysts, including Pt-, Pd-, Ag- and Au-, Ru-based catalysts is given. Furthermore, due to the relatively narrow operating temperature window of full NH3 conversion, high selectivity to N2O and NOx as well as high costs of noble metal-based catalysts, recent developments are aimed at combining the advantages of noble metals and transition metals. Thus, also a brief overview is provided about the design of the bifunctional catalysts (i.e., as dual-layer catalysts, mixed form (mechanical mixture), hybrid catalysts having dual-layer and mixed catalysts, core-shell structure, etc.). Finally, the general conclusions together with a discussion of promising research directions are provided.
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Shanghai Cooperation Organization as a Counterbalance against the United StatesDauekeev, Bakhtiyar T. 13 April 2011 (has links)
No description available.
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1H NMR spectroscopic elucidation in solution of the kinetics and thermodynamics of spin crossover for an exceptionally robust Fe2+ complexPetzold, Holm, Djomgoue, Paul, Hörner, Gerald, Speck, J. Matthäus, Rüffer, Tobias, Schaarschmidt, Dieter 15 September 2016 (has links) (PDF)
A series of Fe2+ spin crossover (SCO) complexes [Fe(5/6)]2+ employing hexadentate ligands (5/6) with cis/trans-1,2-diamino cyclohexanes (4) as central building blocks were synthesised. The ligands were obtained by reductive amination of 4 with 2,2′-bipyridyl-6-carbaldehyde or 1,10-phenanthroline-2-carbaldehyde 3. The chelating effect and the rigid structure of the ligands 5/6 lead to exceptionally robust Fe2+ and Zn2+ complexes conserving their structure even in coordinating solvents like dmso at high temperatures. Their solution behavior was investigated using variable temperature (VT) 1H NMR spectroscopy and VT Vis spectroscopy. SCO behavior was found for all Fe2+ complexes in this series centred around and far above room temperature. For the first time we have demonstrated that the thermodynamics as well as kinetics for SCO can be deduced by using VT 1H NMR spectroscopy. An alternative scheme using a linear correction term C1 to model chemical shifts for Fe2+ SCO complexes is presented. The rate constant for the SCO of [Fe(rac-trans-5)]2+ obtained by VT 1H NMR was validated by Laser Flash Photolysis (LFP), with excellent agreement (1/(kHL + kLH) = 33.7/35.8 ns for NMR/LFP). The solvent dependence of the transition temperature T1/2 and the solvatochromism of complex [Fe(rac-trans-5)]2+ were ascribed to hydrogen bond formation of the secondary amine to the solvent. Enantiomerically pure complexes can be prepared starting with R,R- or S,S-1,2-diaminocyclohexane (R,R-trans-4 or S,S-trans-4). The high robustness of the complexes reduces a possible ligand scrambling and allows preparation of quasiracemic crystals of [Zn(R,R-5)][Fe(S,S-5)](ClO4)4·(CH3CN) composed of a 1 : 1 mixture of the Zn and Fe complexes with inverse chirality. / Dieser Beitrag ist aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.
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