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[EN] The aim of this work is to present the basic concepts of topological band theory, restricted to two-dimensional insulators that can be characterized by the Chern number (AQHE systems), and to theoretically and computationally study the model for a honeycomb lattice proposed by Haldane. For that purpose, the tight-binding approximation will be used, with the help of second quantization formalism. [ES] El objetivo de este trabajo es presentar los conceptos básicos de la teoría de bandas topológicas, restringidos a los aislantes bidimensionales que pueden ser caracterizados por el número de Chern (sistemas AQHE), y estudiar teórica y computacionalmente el modelo para una red de panal propuesto por Haldane. Para ello, se utilizará la aproximación de enlace estrecho, con la ayuda del formalismo de segunda cuantificación.

Phenol biodegradation in batch systems using Cupriavidus taiwanesis 187 has been experimentally studied. To determine the various parameters of a kinetic model, combinations of rearranged equations have been evaluated using inverse polynomial techniques for parameter estimation. The correlations between lag phase and phase concentration suggest that considering phenol inhibition in kinetic analysis is helpful for characterizing phenol degradation. This study proposes a novel method to determine multiplicity of steady states in continuous stirred tank reactors (CSTRs) in order to identify the most appropriate kinetics to characterize the dynamics of phenol biodegradation.

Bioconversion kinetics of gamma-HCH and biological growth kinetics of Pseudomonas aeruginosa degrading technical HCH was investigated in flask experiments under aerobic condition. Degradation studies for various isomers of technical HCH were also performed. The biodegradation of the most persistent beta\-HCH and delta-HCH isomers was also observed. At lower technical HCH concentrations (1-10mg/l), above 99% of the degradation was observed whereas at higher concentration (20-50 mg/l), the degradation efficiency was dropped. This may be due to inhibitory effect of technical HCH at higher concentrations. The technical HCH inhibitory behavior and bacterial growth kinetics could be correlated well by simple Haldane's growth kinetic model. The value of decay and yield coefficient was also determined. Further experimental results also revealed that degradation of the gamma-HCH isomer is faster (after incubation of 5 days) in the presence of other isomers of technical HCH, whereas gamma-HCH alone does not degrade even after a long period of incubation (14 days), but isomerizes to alpha-HCH isomer by the P. aeruginosa. The rate constant for the bioisomerization was found to be 0.0474 day(-1). The above estimated parameters (maximum specific growth rate, half saturation coefficient, inhibition constant, decay coefficient, yield coefficient and bioisomerization rate) are invariably required for the design and simulation of batch and continuous bioreactors treating HCH containing wastewaters. (c) 2007