The use of Fenton＇s reagent （Fe^2＋/H2O2） and Fenton-like reagents containing transition metals of Cu（Ⅱ）, Zn（Ⅱ）, Co（Ⅱ）, and Mn（Ⅱ） for an alum sludge conditioning to improve its dewaterability was invest...The use of Fenton＇s reagent （Fe^2＋/H2O2） and Fenton-like reagents containing transition metals of Cu（Ⅱ）, Zn（Ⅱ）, Co（Ⅱ）, and Mn（Ⅱ） for an alum sludge conditioning to improve its dewaterability was investigated. The results obtained were compared with those obtained from conditioning the same alum sludge using cationic and anionic polymers. Experimental results show that Fenton＇s reagent was the best among the Fenton and Fenton-like reagents for the alum sludge conditioning. A considerable effectiveness of capillary suction time （CST） reduction efficiency of 47% can be achieved under test conditions of Fe^2＋/H2O2 = 20/125 mg/g DS （dry solid） and pH 6.0. The observation of floc-like particles after Fenton＇s reagent conditioning of alum sludge suggested that the mechanism of Fenton＇s reagent conditioning was different from that of polymer conditioning. In spite of the lower efficiency in the CST reduction of Fenton＇s reagent in alum sludge conditioning compared to that of polymer conditioning, Fenton＇s reagent offers a more environmentally safe option. Tiffs study provided an example of proactive treatment engineering, which is aimed at seeking a safe alternative to the use of polymers in sludge conditioning towards achieving a more sustainable sludge management strategy.展开更多
A sensitive polymer diaphragm based fiber Fabry-Perot （F-P） sensor for aeroacoustic wave measurement is presented. A novel polymer material poly （phthalazinone ether sulfone ketone） （PPESK） diaphragm is used as ...A sensitive polymer diaphragm based fiber Fabry-Perot （F-P） sensor for aeroacoustic wave measurement is presented. A novel polymer material poly （phthalazinone ether sulfone ketone） （PPESK） diaphragm is used as the acoustic sensing element. The effective dimensions of the diaphragm are 4 mm in diameter and 6 μm in thickness. Owing to the good mechanical and optical features of the diaphragm and application of the interferometric/intensity demodulation, a system sensitivity of 31 mV/Pa is achieved in the frequency range of 0.1-12.7 kHz, and a signal-to-noise ratio （SNR） of 29 dB at 1 kHz is obtained. The linear response of the sensor is from 0.35 to 2.82 Pa, corresponding to 85 103 dB sound pressure level （SPL） （re： 20 μPa）. The sensor has the potential to be used as a universal and low-cost optical microphone.展开更多
基金The first author would like to appreciate Ministry of Higher Education, Missions Department, Egypt for the fi- nancial support granted through Channel Scheme Mission.
文摘The use of Fenton＇s reagent （Fe^2＋/H2O2） and Fenton-like reagents containing transition metals of Cu（Ⅱ）, Zn（Ⅱ）, Co（Ⅱ）, and Mn（Ⅱ） for an alum sludge conditioning to improve its dewaterability was investigated. The results obtained were compared with those obtained from conditioning the same alum sludge using cationic and anionic polymers. Experimental results show that Fenton＇s reagent was the best among the Fenton and Fenton-like reagents for the alum sludge conditioning. A considerable effectiveness of capillary suction time （CST） reduction efficiency of 47% can be achieved under test conditions of Fe^2＋/H2O2 = 20/125 mg/g DS （dry solid） and pH 6.0. The observation of floc-like particles after Fenton＇s reagent conditioning of alum sludge suggested that the mechanism of Fenton＇s reagent conditioning was different from that of polymer conditioning. In spite of the lower efficiency in the CST reduction of Fenton＇s reagent in alum sludge conditioning compared to that of polymer conditioning, Fenton＇s reagent offers a more environmentally safe option. Tiffs study provided an example of proactive treatment engineering, which is aimed at seeking a safe alternative to the use of polymers in sludge conditioning towards achieving a more sustainable sludge management strategy.
基金supported by the National Natural Science Foundation of China under Grant No.60677010
文摘A sensitive polymer diaphragm based fiber Fabry-Perot （F-P） sensor for aeroacoustic wave measurement is presented. A novel polymer material poly （phthalazinone ether sulfone ketone） （PPESK） diaphragm is used as the acoustic sensing element. The effective dimensions of the diaphragm are 4 mm in diameter and 6 μm in thickness. Owing to the good mechanical and optical features of the diaphragm and application of the interferometric/intensity demodulation, a system sensitivity of 31 mV/Pa is achieved in the frequency range of 0.1-12.7 kHz, and a signal-to-noise ratio （SNR） of 29 dB at 1 kHz is obtained. The linear response of the sensor is from 0.35 to 2.82 Pa, corresponding to 85 103 dB sound pressure level （SPL） （re： 20 μPa）. The sensor has the potential to be used as a universal and low-cost optical microphone.
