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91.
92.
Isobel M. L. Robertson 《The Journal of the Operational Research Society》1982,33(6):517-525
After the reorganisation of local government in Scotland in 1975, all councils were asked to make a comprehensive review of electoral areas. Although parity of population was a prime concern, attention had to be given also to the compactness and contiguity of districts. The Act also recommended that local communities should be kept intact and that boundaries should accord with ground features. The allocative part of the Törnqvist location-allocation technique was used in the first stage of partitioning in certain Regions to provide a basic framework for an apportionment pattern. Although this algorithm maximises compactness, it can produce sub-optimal results with a high degree of parity. Final adjustment of boundaries depended on detailed local knowledge. 相似文献
93.
Murray V. Baker David H. Brown Peter V. Simpson Brian W. Skelton Allan H. White Charlotte C. Williams 《Journal of organometallic chemistry》2006,691(26):5845-5855
New Pd(II), Pt(II) and Rh(I) N-heterocyclic carbene (NHC) complexes containing two NHC units linked by an ortho-xylyl group are described and structurally and spectroscopically characterised. The Pt(II) complexes represent the first examples of Pt-bis(NHC) complexes where the NHC units are linked by an ortho-xylyl group. Functionalisation of the bis(NHC) ligands with heptyl groups has been used as a means of enhancing the solubility of the complexes, in order to facilitate spectroscopic characterisation and catalytic studies. The catalytic activity of the palladium(II) complexes in Heck and Suzuki cross-coupling reactions has been examined to investigate any effects of the diverse structural changes, though these appear to be insignificant. 相似文献
94.
Dedicated to Bernard Coleman on the occasion of his 60th birthday 相似文献
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96.
R. Alan Aitken Ian Gosney Hugh Farries Michael H. Palmer Isobel Simpson J.I.G. Cadogan Edward J. Tinley 《Tetrahedron》1985,41(7):1329-1346
The reactivity of a series of bicyclic olefins with nitrenes is profoundly influenced by the nature of remote functional groups. There is a marked lack of reactivity for reactions with carboethoxynitrene as compared to phthalimidonitrene which is distinctly nucleophilic in character. An explanation for the reluctance to form aziridines is offered in terms of orbital interactions between the distant groups and the olefinic bond, making the latter remarkably electron deficient as evidenced by UV-photoelectron spectrosoopy. Because of the complexity of the spectra, identification of the Ip associated with the reactive π-centre was made by recourse to ab initio configuration interaction calculations for key members of the series. 相似文献
97.
Deutero-alcohol (2b) was prepared and dehydrated with H2SO4Ac2OHOAc to give a kinetic isotope effect demonstrating anion mobility within the intermediate carbocation-anion ion pair. 相似文献
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