To achieve advanced nitrogen removal from actual municipal sewage,a novel multistage anoxic/aerobic process with sludge regeneration zone(R-MAO)was developed.The reactor was used to treat actual domestic sewage and th...To achieve advanced nitrogen removal from actual municipal sewage,a novel multistage anoxic/aerobic process with sludge regeneration zone(R-MAO)was developed.The reactor was used to treat actual domestic sewage and the nitrogen removal capacity of the sludge regeneration zone(R zone)was investigated during the long-term operation.The best performance was obtained at the R zone’s Oxidation-Reduction Potential(ORP)of-50±30 mV and hydraulic residence times(HRT)of 1.2 hr.The average effluent COD,TN,NH_(4)^(+)-N and NO_(3)^(−)-N of the R-MAO process were 18.0±2.3,7.5±0.6,1.0±0.5 and 4.6±0.4 mg/L,respectively,with the corresponding removal efficiency of COD,TN and NH_(4)^(+)-N were 92.9%±1.0%,84.1%±1.5% and 97.5%±1.1%.Compared to the sole MAO system,the TN removal efficiency of the R-MAO increased by 10.1%.Besides,under the optimal conditions,the contribution of the R zone in the R-MAO that removal COD,TN,NH_(4)^(+)-N and NO_(3)^(−)-N were 0.36,0.15,0.032 and 0.82 g/day.High-throughput sequencing results showed that uncultured_bacterium_f_Burkholderiaceae(5.20%),OLB8(1.04%)and Ottowia(1.03%)played an important role in denitrification in the R zone.This study provided effective guidance for the design and operation of the R-MAO process in domestic sewage treatment.展开更多
复合材料已成为现代飞机制造的非常重要的选材,复合材料结构R区缺陷会影响其受力和传载。R区开敞性差、声波反射复杂等影响超声检测及其缺陷识别与定量评估。为此,基于超声波在R-区的反射行为,利用宽带窄脉冲超声反射回波时域特征和成...复合材料已成为现代飞机制造的非常重要的选材,复合材料结构R区缺陷会影响其受力和传载。R区开敞性差、声波反射复杂等影响超声检测及其缺陷识别与定量评估。为此,基于超声波在R-区的反射行为,利用宽带窄脉冲超声反射回波时域特征和成像特征进行复合材料结构R区缺陷检测与量化评估及层深定位。计算结果表明,入射角小于3°时,可以获得较好的声波透射效果。试验结果表明,入射声波在R区蒙皮表面、底面、层间、分层形成的反射信号具有明显不同的时域特征和B-扫描图像特征,对于12个铺层的R-区蒙皮,不同深度分层波幅变化不超过2.5 d B;分层深度定位准确性达1个铺层内;采用水膜方法可以获得稳定的超声耦合效果;利用所使用的换能器及检测系统的超声B-扫描成像,可以直观地再现入射声波在复合材料R区的反射行为,有效地揭示R区分层缺陷深度分布、取向长度;检测分辨率和表面检测盲区可以达到单个复合材料铺层的厚度,约0.125 mm。解剖结果验证了实际超声检测结果的正确性。为复合材料结构R区提供了一种非常有效的检测技术和缺陷定性定量方法,已经得到了非常重要的实际检测应用。展开更多
基金supported by a project of Shenzhen Science and Technology Plan (No. KCXFZ202002011006362)Project of Central and Southern China Municipal Engineering Design & Research Institute Co.,Ltd. (Technology Development 2019)
文摘To achieve advanced nitrogen removal from actual municipal sewage,a novel multistage anoxic/aerobic process with sludge regeneration zone(R-MAO)was developed.The reactor was used to treat actual domestic sewage and the nitrogen removal capacity of the sludge regeneration zone(R zone)was investigated during the long-term operation.The best performance was obtained at the R zone’s Oxidation-Reduction Potential(ORP)of-50±30 mV and hydraulic residence times(HRT)of 1.2 hr.The average effluent COD,TN,NH_(4)^(+)-N and NO_(3)^(−)-N of the R-MAO process were 18.0±2.3,7.5±0.6,1.0±0.5 and 4.6±0.4 mg/L,respectively,with the corresponding removal efficiency of COD,TN and NH_(4)^(+)-N were 92.9%±1.0%,84.1%±1.5% and 97.5%±1.1%.Compared to the sole MAO system,the TN removal efficiency of the R-MAO increased by 10.1%.Besides,under the optimal conditions,the contribution of the R zone in the R-MAO that removal COD,TN,NH_(4)^(+)-N and NO_(3)^(−)-N were 0.36,0.15,0.032 and 0.82 g/day.High-throughput sequencing results showed that uncultured_bacterium_f_Burkholderiaceae(5.20%),OLB8(1.04%)and Ottowia(1.03%)played an important role in denitrification in the R zone.This study provided effective guidance for the design and operation of the R-MAO process in domestic sewage treatment.
文摘复合材料已成为现代飞机制造的非常重要的选材,复合材料结构R区缺陷会影响其受力和传载。R区开敞性差、声波反射复杂等影响超声检测及其缺陷识别与定量评估。为此,基于超声波在R-区的反射行为,利用宽带窄脉冲超声反射回波时域特征和成像特征进行复合材料结构R区缺陷检测与量化评估及层深定位。计算结果表明,入射角小于3°时,可以获得较好的声波透射效果。试验结果表明,入射声波在R区蒙皮表面、底面、层间、分层形成的反射信号具有明显不同的时域特征和B-扫描图像特征,对于12个铺层的R-区蒙皮,不同深度分层波幅变化不超过2.5 d B;分层深度定位准确性达1个铺层内;采用水膜方法可以获得稳定的超声耦合效果;利用所使用的换能器及检测系统的超声B-扫描成像,可以直观地再现入射声波在复合材料R区的反射行为,有效地揭示R区分层缺陷深度分布、取向长度;检测分辨率和表面检测盲区可以达到单个复合材料铺层的厚度,约0.125 mm。解剖结果验证了实际超声检测结果的正确性。为复合材料结构R区提供了一种非常有效的检测技术和缺陷定性定量方法,已经得到了非常重要的实际检测应用。
