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Abstract We analyze the efficiency of the international management of the Bay of Biscay anchovy. While a sharing agreement between France and Spain has been in place since 1992, the fish stock collapsed in 2005 and the fishery closed from 2005 to spring 2010. We consider differences in production technologies between both countries and calibrate our model using data from 1987 to 2009. Our results suggest two sources of rent dissipation under the existing sharing agreement: inefficient quota allocation and production inefficiencies due to inflexible national regulations. We discuss several alternatives to improve management. 相似文献
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Duer MJ García F Goodman JM Hehn JP Kowenicki RA Naseri V McPartlin M Stead ML Stein R Wright DS 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(4):1251-1260
The reaction of MeAlCl2 with 'PhPLi2' in THF gives [{MeAl(PPh)3Li(4).3 THF}4(mu4-Cl)]-Li+ (1). The GaIII and InIII analogues, [{MeE(PPh)3Li(4).3 THF}4(mu4-Cl)]-Li+(THF)3 (E=Ga (2), In (3)), are obtained by the in situ reactions of MeECl2 with PhPLi2 in THF. For all of the complexes, the cage anions have an unusual cubic arrangement that is similar to a zeolite, and contain large voids (ca. 17 A). The location of the Li+ counterions in 1-3 and their coordination environment appears to subtly reflect variations in packing and lattice energy. Whereas in 1 highly mobile, loosely coordinated Li+ counterions are present, 2 and 3 contain less mobile THF-solvated counterions within the cavities. X-ray crystallographic and solid-state NMR studies are reported on 1-3, together with model DFT calculations on the selectivity of halide coordination. 相似文献
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A newly developed interface coupling a CHN combustion device (elemental analyser 'EA') to an isotope ratio mass spectrometer is described and evaluated. The purpose of the device is to extend the dynamic range of delta(13)C and delta(15)N analysis from less than 2 orders of magnitude to more than 3 orders of magnitude. Carbon isotope ratio measurements of atropine as a model compound have been performed analysing between 1 μg to 5 mg C with acceptable to excellent precision (0.6 to 0.06 per thousand, delta-notation). The correction due to the blank signal is critical for sample amounts smaller than 4 μg C. The maximum sample weight is determined by the combustion capacity of the EA. Larger sample amounts are measured using dilution of a small part of the EA effluent with helium. The dilution mechanism works virtually free of isotope fractionation. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
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García F Goodman JM Kowenicki RA Kuzu I McPartlin M Silva MA Riera L Woods AD Wright DS 《Chemistry (Weinheim an der Bergstrasse, Germany)》2004,10(23):6066-6072
The structures of the host-guest complexes [[[[P(mu-NtBu)]2(mu-NH)]5]I]-.[Li(thf)4]+ [2.I[Li(thf)4]] and [[[P(mu-NtBu)]2(mu-NH)]5].HBr.THF (2.HBr.THF) show that increased distortion of the framework of the pentameric macrocycle [[[P(mu-NtBu)]2(mu-NH)]5] (2) occurs with the larger halide ions. Theoretical studies show that the thermodynamic stabilities of the model host-guest anions [2.X]- (X=Cl, Br, I) are in the order Cl- approximately Br->I-, that is, the reverse of the templating trend observed experimentally. These studies support the view that the selection of the pentamer 2 over the tetramer [[[P(mu-NtBu)]2(mu-NH)]4] (1) is kinetically controlled, a conclusion which is also consistent with the previous observation that the frameworks of 1 and 2 are not in dynamic equilibrium with each other. 相似文献
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Ion L Morales D Nieto S Pérez J Riera L Riera V Miguel D Kowenicki RA McPartlin M 《Inorganic chemistry》2007,46(7):2846-2853
Compounds [Mo(CO)4(N-N)] (N-N = 4,4'-bis((4-methylphenyl)carbamoyl)-2,2'-bipyridine, bipy', 1; or 2,2'-biimidazole, H2biim, 2), [MoCl(eta3-methallyl)(CO)2(N-N)] (N-N = bipy', 3; H2biim, 4), and [Mo(eta3-methallyl)(CNtBu)(CO2)(N-N)]BAr'4 (Ar' = 3,5-bis(trifluoromethyl)phenyl; N-N= bipy', 5; H2biim, 6) were synthesized and characterized, and their behavior toward anions was investigated in solution (IR and 1H NMR) and in solid state (X-ray diffraction). 相似文献
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LUDVÍK BENEŠ KLÁRA MELÁNOVÁ JAN SVOBODA VÍTĚZSLAV ZIMA 《Journal of inclusion phenomena and macrocyclic chemistry》2006,55(3-4):289-293
Intercalates of o-, m-, and p-toluidine into α-Zr(HPO4)2 · H2O were prepared and characterized by powder X-ray diffraction, thermogravimetric analysis and infrared spectroscopy. As follows from IR, toludine molecules are protonated in the interlayer space. Toluidine molecules are arranged in a bimolecular way in the intercalates containing more than 1.5 toluidine molecules per Zr atom. On the other hand, a monolayer of the toluidine molecules is supposed in the intercalates with less than one toluidine molecule per Zr atom. 相似文献