RESUMO
Groundwater contamination due to releases of petroleum products is a major environmental concern in many urban districts and industrial zones. Over the past years, a few studies were undertaken to address in situ bioremediation processes coupled with contaminant transport in two- or three-dimensional domains. However, they were concentrated on natural attenuation processes for petroleum contaminants or enhanced in situ bioremediation processes in laboratory columns. In this study, an integrated numerical and physical modeling system is developed for simulating an enhanced in situ biodegradation (EISB) process coupled with three-dimensional multiphase multicomponent flow and transport simulation in a multi-dimensional pilot-scale physical model. The designed pilot-scale physical model is effective in tackling natural attenuation and EISB processes for site remediation. The simulation results demonstrate that the developed system is effective in modeling the EISB process, and can thus be used for investigating the effects of various uncertainties.
Assuntos
Simulação por Computador , Monitoramento Ambiental , Poluição Ambiental , Modelos Teóricos , Petróleo , Poluentes Químicos da Água , Biodegradação Ambiental , Petróleo/toxicidade , Medição de Risco , Movimentos da Água , Poluentes Químicos da Água/toxicidadeRESUMO
The purpose of this in vitro study was to determine the combined effects of ND:YAG laser irradiation and 2% NaF on caries-like lesion formation in human enamel.There were four groups:(1)control;(2)Nd:YAG laser only;(3)2%NaF only;(4)Nd:YAG laser before 2% NaF.The result show the lesion body depths were significant differences between the control group and all treatment group,and between Nd:YAG laser before 2% NaF group and both Nd:YAG laser group and 2% NaF group(P<0.05).The surface zone depths between Nd:YAG laser before 2% NaF group and both 2% NaF group and both 2% NaF group and control group were also significantly different(P<0.05).
