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Online UV-Vis spectrophotometer technology as accurate, convenient and fast monitoring method was used to detect instantaneous dye concentration in aqueous medium. Ferrous ion coupling with Persulphate to degrade methylene blue (MB) exhibited a very high degradation rate, and therefore online UV-Vis spectrophotometer showed great advantage in this study. The effects of ferrous ion concentration, sodium Persulphate concentration, pH value and initial MB concentration on MB degradation were investigated. The online spectrophotometer could minimize the systematic error caused by the termination of adding chemicals and manual operation. At room temperature, the optimal condition was acquired with 73.6% MB removal after 100s at neutral medium when initial ferrous dosage and sodium Persulphate were 1.25 mmol/L and 0.2 mmol/L, respectively. Fe2+/S2O8 2- system exhibited a great degradation efficiency in acidic or neutral environment.

Objective: To investigate the related factors that may influence the effect hearing aid for sensorineural hearing loss patients., Method: Sixty cases with moderate to severe sensorineural hearing loss were selected. Audiological measurements were performed before and after hearing aiding. Factor analysis was carried out., Result: The unaided hearing level (UHL), Speech perception thresher (SPT), speech recognition thresher (SRT), speech recognition score (SRS) and aided hearing level (AHL) have notable influence on the effect of hearing aid fitting. The most comfortable level (MCL), age, education period, hearing loss duration and aided duration also have some influence on the results., Conclusion: Hearing aid is not only a hearing compensating tool, it also has some therapeutic effect as well.