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841.
842.
F C Celentano C Tonani M Fazio E Gianazza P G Righetti 《Journal of biochemical and biophysical methods》1988,16(2-3):109-128
This paper presents the general equations for computing pH, dissociation coefficients, buffering power and ionic strength of pure polyelectrolyte solutions (polyacids, polybases and zwitterionic species with any number of dissociable groups) and mixtures of any number of these species. A program has been written for simulating the behaviour of mixtures containing up to 50 species (including buffers and titrants), each of them with up to 10 dissociable groups. This allowed one to check the equations with the available data on a few oligoprotic species. 相似文献
843.
844.
Vincenzo Cuomo Stefania Pagano Maria Antonietta Pecorella Palma Parascandola 《Biochemical Systematics and Ecology》1987,15(6):635-637
Evidence is given of release of six enzymes activities generally associated with plant material degradation, during in vitro experiments with Corollospora maritima acting upon Posidonia oceanica leaves. The results obtained are discussed in the light of the present knowledge on the role of marine fungi in the biological breakdown and conversion of leaf material in marine ecosystem. 相似文献
845.
846.
847.
The electrochemical reduction of a series of copper(II) complexes with 1,10-o-phenanthrolines, namely the 1:1 and 1:2 metal:ligand complexes with 2,9-dimethylphenanthroline, 4,7-dimethylphenanthroline and unsubstituted phenanthroline, respectively, has been studied in N,N-dimethylformamide using platinum electrodes. As to the 1:2 complexes, the effect of the presence of substituents with different electronic and steric effects on the phenanthroline ligands has been studied with the aim of rationalizing the different values of the standard potentials which have been measured. Furthermore, the possibility of electrogenerating neutral species, with a formally zerovalent copper centre, exhibiting different stability depending on the nature of the ligands, has been ascertained. In out solvent medium, 1:1 complexes have been found to be in equilibrium with the corresponding 1:2 complexes. A scheme for the reduction of solutions of these compounds, including the different equilibria associated to the electrode charge transfers, has been outlined. 相似文献