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[en] Since the oil prices decreased during June 2008, many uncertainties drive the energy markets. The author aims to analyze the future battles around the the dying resources, taking into account that the alternatives sources will need time to develop. The author analyzes also the relation energy and climate in the preservation of the fundamental equilibrium. (A.L.B.)
Journal
[en] There has been a renewed interest to develop new nuclear power systems for commercial deployment. Of the design categories receiving significant attention is molten salts reactors (MSRs). There are many MSR design configurations under development, this paper focuses on the thermal-spectrum, pebble-bed, salt-cooled concept, often referred to as the Fluoride High-temperature Reactor (FHR). Constructing a geometrically accurate model of a pebble bed reactor with double heterogeneity is addressed before any further analysis is conducted. Within the FHR design concept geometric and material parameters can vary considerably. The purpose of the paper is to examine two fundamental design parameters; the level of moderation and the coolant salt selection. Results indicate that additional moderation beyond the graphite in the pebbles is beneficial and alternative salts to 27LiF-BeF2, despite inferior results, do generate an adequately high multiplication factor. (author)
Source
Canadian Nuclear Society, Toronto, Ontario (Canada); 175 Megabytes; ISBN 978-1-926773-28-5; 
; 2019; [6 p.]; 39. Annual CNS conference and 43. CNS/CNA student conference; Ottawa, Ontario (Canada); 23-26 Jun 2019; Available from the Canadian Nuclear Society, Toronto, Ontario (Canada); 2 refs., 4 tabs., 4 figs.
; 2019; [6 p.]; 39. Annual CNS conference and 43. CNS/CNA student conference; Ottawa, Ontario (Canada); 23-26 Jun 2019; Available from the Canadian Nuclear Society, Toronto, Ontario (Canada); 2 refs., 4 tabs., 4 figs.
[en] In this paper we ask whether OPEC still gains from cartelisation in the oil market despite low producer prices and a modest market share. We apply two intertemporal equilibrium models of the global oil market; one consisting of a cartel and a fringe, and one describing a hypothetical competitive market. Comparing the outcome of these models we conclude that there are positive cartelisation gains of about 18 percent in the oil market. In comparison with what Pindyck (1978) found for the 1970s this may be considered as quite modest. Moreover, we study whether the cartelisation gains to OPEC are altered by different moves by non-OPEC producers or consumer countries. Generally, we find that the relative cartelisation gains are unchanged. One exception is exploration activities, where we find that a major increase in non-OPEC reserves could remove the cartelisation gains to OPEC completely. In this case, the OPEC-countries could find themselves better off without the cartel. (author)
Journal
[en] 13C- and 2H-labeled retinal derivatives have been used to assign normal modes in the 1100-1300-cm-1 fingerprint region of the resonance Raman spectra of rhodopsin, isorhodopsin, and bathorhodopsin. On the basis of the 13C shifts, C8-C9 stretching character is assigned at 1217 cm-1 in rhodopsin, at 1206 cm-1 in isorhodopsin, and at 1214 cm-1 in bathorhodopsin. C10-C11 stretching character is localized at 1098 cm-1 in rhodopsin, at 1154 cm-1 in isorhodopsin, and at 1166 cm-1 in bathorhodopsin. C14-C15 stretching character is found at 1190 cm-1 in rhodopsin, at 1206 cm-1 in isorhodopsin, and at 1210 cm-1 in bathorhodopsin. C12-C13 stretching character is much more delocalized, but the characteristic coupling with the C14H rock allows the authors to assign the C12-C13 stretch at ∼1240 cm-1 in rhodopsin, isorhodopsin, and bathorhodopsin. The insensitivity of the C14-C15 stretching mode to N-deuteriation in all three pigments demonstrates that each contains a trans (anti) protonated Schiff base bond. The relatively high frequency of the C10-C11 mode of bathorhodopsin demonstrates that bathorhodopsin is s-trans about the C10-C11 single bond. This provides strong evidence against the model of bathorhodopsin proposed by Liu and Asato, which suggests a C10-C11 s-cis structure. Comparison of the fingerprint modes of rhodopsin with those of the 11-cis-retinal protonated Schiff base in methanol shows that the frequencies of the C-C stretching modes are largely unperturbed by protein binding. The implications of these observations for the mechanism of wavelength regulation in visual pigments and energy storage in bathorhodopsin are discussed
Journal
[en] Solid-state 13C NMR spectra of the M photocycle intermediate of bacteriorhodopsin (bR) have been obtained from purple membrane regenerated with retinal specifically 13C labeled at positions 5, 12, 13, 14, and 15. The M intermediate was trapped at -40 degree C and pH = 9.5-10.0 in either 100 mM NaCl [M (NaCl)] or 500 mM guanidine hydrochloride [M (Gdn-HCl)]. The 13C-12 chemical shift at 125.8 ppm in M (NaCl) and 128.1 ppm in M (Gdn-HCl) indicates that the C13 double-bond C14 double bond has a cis configuration, while the 13C-13 chemical shift at 146.7 ppm in M (NaCl) and 14.57 ppm in M (Gdn-HCl) demonstrates that the Schiff base in unprotonated. The principal values of the chemical shift tensor of the 13C-5 resonance in both M (NaCl) and M (Gdn-HCl) are consistent with a 6-s-trans structure and a negative protein charge localized near C-5 as was observed in dark adapted bR. The ∼5 ppm upfield shift of the 13C-5 M resonance relative to 13C-5 bR568 and bR548 is attributed to an unprotonated Schiff base in the M chromophore. Of particular interest in this study were the results obtained from 13C-14 M. In M (NaCl), a dramatic upfield shift was observed for the 13C-14 resonance relative to unprotonanted Schiff base model compounds. In contrast, in M (Gdn-HCl) the 13C-14 resonance was observed at 125.7 ppm. The different 13C-14 chemical shifts in these two M preparations may be explained by different Cdouble-primeN configurations of the retinal-lysine Schiff base linkage, namely, syn in NaCl and anti in guanidine hydrochloride
Journal
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