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State Lies (state + ly)
Selected AbstractsVoluntary environmental policy instruments: two Irish success stories?ENVIRONMENTAL POLICY AND GOVERNANCE, Issue 1 2002Brendan Flynn Voluntary environmental policy instruments have attracted much interest in recent years, yet they remain firmly established only in the industrial setting of the typical environmental policy ,leader' states such as the Netherlands or Germany. This paper examines two Irish examples of innovative voluntary agreements, a farm plastic recycling scheme and a bird conservation project. These both suggest that the voluntary approach can be applied successfully outside the typical industrial sector. Noteworthy in explaining the emergence of the two case studies here was a policy transfer effect from the UK, involving organized Irish farming interests and Irish bird conservationists. A fear of impending state legislation, which is often cited as a vital precondition for successful voluntary approaches, was actually less important than the autonomous initiative of the interest groups themselves. It is suggested that a more important role for the state lies in ensuring good policy co-ordination. A concluding discussion examines the general problems and potential of relying on interest groups to transfer and implement innovative voluntary environmental policy instruments. Copyright © 2002 John Wiley & Sons, Ltd. and ERP Environment [source] Theory of chemical bonds in metalloenzymes.INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 4 2008Abstract A first principle investigation has been carried out for intermediate states of the catalytic cycle of a cytochrome P450. To elucidate the whole catalytic cycle of P450, the electronic and geometrical structures are investigated not only at each ground state but also at low-lying energy levels. Using the natural orbital analysis, the nature of chemical bonds and magnetic interactions are investigated. The ground state of the Compound 1 (cpd1) is calculated to be a doublet state, which is generated by the antiferromagnetic coupling between a triplet Fe(IV)O moiety and a doublet ligand radical. We found that an excited doublet state of the cpd1 is composed of a singlet Fe(IV)O and a doublet ligand radical. This excited state lies 20.8 kcal mol,1 above the ground spin state, which is a non-negligible energy level as compared with the activation energy barrier of ,E# = 26.6 kcal mol,1. The reaction path of the ground state of cpd1 is investigated on the basis of the model reaction: 3O(3p) + CH4. The computational results suggest that the reactions of P450 at the ground and excited states proceed through abstraction (3O-model) and insertion (1O-model) mechanisms, respectively. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 [source] Density functional study of the heme moiety of cytochrome c,,INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 5 2005Anil Kumar Abstract A model of cytochrome c (Cyt-c) including the porphyrin ring, a methionine residue (Met), and the imidazole ring of histidine (His), the latter two being situated above and below the iron (Fe) atom of the porphyrin ring, was studied using Density Functional Theory (DFT). The geometries of the model Cyt-c complex with the Fe atom in two different charge states were fully optimized, i.e., in singlet and triplet states for Fe and in doublet and quartet states for Fe3+. The B3LYP method of DFT along with the 3-21G* basis set for C, H, N, and O atoms and the Lanl2dz basis set for the Fe atom was used. We found that with Fe3+, the doublet spin state is the ground state and the quartet state lies slightly above it. The geometry of the singlet spin state is similar to that of the doublet and quartet states. However, methionine has different conformations when Fe has zero charge (singlet, triplet states) relative to the situation when Fe has +3 charges (doublet, quartet states). The Met chain is folded instead of remaining extended in going from the singlet or triplet spin state to the doublet or quartet state and the folding is stabilized by an intramolecular CH..O hydrogen bond. The optimized geometrical parameters of the model of Cyt-c are usually in satisfactory agreement with those observed experimentally. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 [source] The Reaction of Ozone with the Hydroxide Ion: Mechanistic Considerations Based on Thermokinetic and Quantum Chemical Calculations and the Role of HO4, in Superoxide DismutationCHEMISTRY - A EUROPEAN JOURNAL, Issue 4 2010Gábor Merényi Prof. Abstract The reaction of OH, with O3 eventually leads to the formation of . OH radicals. In the original mechanistic concept (J. Staehelin, J. Hoigné, Environ. Sci. Technol.1982, 16, 676,681), it was suggested that the first step occurred by O transfer: OH,+O3,HO2,+O2 and that . OH was generated in the subsequent reaction(s) of HO2, with O3 (the peroxone process). This mechanistic concept has now been revised on the basis of thermokinetic and quantum chemical calculations. A one-step O transfer such as that mentioned above would require the release of O2 in its excited singlet state (1O2, O2(1,g)); this state lies 95.5,kJ,mol,1 above the triplet ground state (3O2, O2(3,g,)). The low experimental rate constant of 70,M,1,s,1 is not incompatible with such a reaction. However, according to our calculations, the reaction of OH, with O3 to form an adduct (OH,+O3,HO4,; ,G=3.5,kJ,mol,1) is a much better candidate for the rate-determining step as compared with the significantly more endergonic O transfer (,G=26.7,kJ,mol,1). Hence, we favor this reaction; all the more so as numerous precedents of similar ozone adduct formation are known in the literature. Three potential decay routes of the adduct HO4, have been probed: HO4,,HO2,+1O2 is spin allowed, but markedly endergonic (,G=23.2,kJ,mol,1). HO4,,HO2,+3O2 is spin forbidden (,G=,73.3,kJ,mol,1). The decay into radicals, HO4,,HO2.+O2.,, is spin allowed and less endergonic (,G=14.8,kJ,mol,1) than HO4,,HO2,+1O2. It is thus HO4,,HO2.+O2., by which HO4, decays. It is noted that a large contribution of the reverse of this reaction, HO2.+O2.,,HO4,, followed by HO4,,HO2,+3O2, now explains why the measured rate of the bimolecular decay of HO2. and O2., into HO2,+O2 (k=1×108,M,1,s,1) is below diffusion controlled. Because k for the process HO4,,HO2.+O2., is much larger than k for the reverse of OH,+O3,HO4,, the forward reaction OH,+O3,HO4, is practically irreversible. [source] | ||||||||||