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61.
Summary Solubilities of molybdenum(O)-diimine-tetracarbonyl complexes containing pyridyl-primary amine Schiff base or substituted 1,4-diazabutadiene ligands are reported, for a variety of non-aqueous solvents, and for toluene + heptane, toluene + methanol, and methanol-rich methanol + water mixed solvents. Enthalpies and entropies of solution for several of these complexes in a selection of solvents have been derived from temperature variation of solubilities. These results, together with new data on solvent effects on infrared and n.m.r. (1H, 13C, 95Mo) spectra and published data on solvatochromism of this family of compounds, are discussed in relation to solvation of these complexes in pure and mixed solvents. 相似文献
62.
Xiaoming Xu Xingzhe Ding Long Ling John O. Burgess 《Journal of polymer science. Part A, Polymer chemistry》2005,43(14):3153-3166
Novel dimethacrylate monomers containing bis(aminodiacetic acid) chelating ligands with or without additional hydroxyl groups were synthesized, starting from 2,2‐bis(4‐hydroxy‐3‐methylphenyl)propane. The structures of the monomers were characterized by electrospray mass spectrometry (ESMS), 1H NMR, and 13C NMR. The structures and relative stability of fluoride‐releasing monomers containing one or more ternary zirconium fluoride complex moieties were studied by ESMS. The most stable ternary zirconium fluoride complex was in the form of [LZrF]?, where H4L is the monomer containing bis(aminodiacetic acid) without additional hydroxyl groups. The synthesized monomer was photopolymerized with camphorquinone and 1‐phenyl‐1,2‐propane‐dione as initiators and N,N‐dimethylaminoethyl methacrylate as the accelerator. The fluoride release, fluoride recharge, compressive strength, and flexure strength were tested on the experimental dental composite containing 13.7 wt % synthesized monomer and three commercial flowable dental composites. The results showed that the experimental composite has significantly higher fluoride release and recharge capabilities than the commercial flowable composites. The compressive strength was comparable to that of the commercial materials. The water sorption and solubility met the requirement of the ISO Specification 4049. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3153–3166, 2005 相似文献
63.
Rate laws and kinetic parameters are reported for substitution at titanium(IV) complexes Ti(LL)2X2, where LLH=cyclopentadiene, the 4-pyrone ethylmaltol, several 4-pyridinones, and related ligands, and X=halide or alkoxide, in acetonitrile solution at 298.2 K. Reactivities are discussed in terms of the nature of the leaving group, the entering group and the non-leaving ligand LL?. Activation volumes of ?15 and ?12 cm3 mol?1 have been determined for thiocyanate attack at Ti(cp)2Cl2 and Ti(etmalt)2Cl2 respectively. Substitution mechanisms are discussed in the light of the kinetic parameters obtained. 相似文献
64.
The angles a fourth-harmonic holographic interferometer probing beam is refracted upon passing through a neodymium laser-produced plasma have been measured by varying the focus during reconstruction of the hologram. A method (not requiring the numerical inversion of an integral equation) for using such refraction measurements to give the plasma electron density profile is shown to produce a profile in agreement with that obtained from the phase information on the reconstructed in-focus interferogram. 相似文献
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Michael J. Blandamer John Burgess Manolo Balon Pilar Guardado Alfredo Maestre 《Transition Metal Chemistry》1988,13(4):313-316
Summary Partial molal volumes of the perchlorate or chloride salts of several tris-diimine-iron(II) cations have been determined in aqueous and methanol-water solutions by vibrating-tube densimetry. Partial molal volumes of the cations at infinite dilution have been estimated for aqueous solution, and compared with values for related cations. Trends of limiting partial molal volumes for perchlorate salts in methanol-water media are compared with trends in transfer chemical potentials for the respective cations; both are discussed in terms of ligand-dependent preferential solvation behaviour. 相似文献
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The carbene complex can mediate hydrogenations of dienes with up to 20:1.0 diastereoselectivity and 99% ee; the scope and limitations of these reactions were investigated. 相似文献