Temperature dependence of the photoinduced EL2*→EL20 recovery process observed by infrared absorption
The infrared absorption technique is used to measure the photoinduced recovery of the EL2 defect from its metastable state (EL2*) to its normal state (EL20) in semi‐insulating GaAs. This recovery is induced by irradiating photoquenched samples with 0.90 or 1.46 eV light for 60 min at various temperatures between 10 and 110 K. The recovery process is found to be highly temperature and sample dependent. It is concluded that the results are related to the presence of other defects and impurities (traps) which interact with EL2 at low temperatures.
This paper deals with the study on the extracting conditions of flavonoid from tea.Response surface methodology was used to obtain the optimum extracting conditions by Design-Expert 6.0.The research findings show that the optimum extracting conditions were as follows:extracting 60 min,water temperature 80℃,60%alcohol,10 times volumes.