造纸废水处理过程的高斯过程回归软测量建模

针对造纸废水处理系统的时变性、非线性和复杂性等特点,本文提出一种基于高斯过程回归的软测量模型.基于平方指数协方差、线性协方差和周期性协方差函数组合构建了7种高斯过程回归模型,分别对出水化学需氧量和出水悬浮固形物浓度进行回归预测.此外,还对比了多元线性回归模型、主成分回归模型、偏最小二乘模型、人工神经网络模型和高斯回归模型的预测效果.对比计算结果表明无论是对输出变量的训练拟合还是预测,高斯过程回归模型的拟合效果均优于非高斯过程回归模型.高斯过程回归模型的预测结果表明：对于出水化学需氧量,线性协方差函数与周期性协方差函数的组合模型可以取得最好的预测结果;对于出水悬浮固形物,平方指数协方差函数与线性协方差函数组合模型可以取得最好的预测结果.     

磁性Fen+@GO非均相Fenton催化氧化亚甲基蓝

采用化学共沉淀法制备了磁性Feⁿ⁺@GO（MFGO）纳米复合材料,并将其用于非均相Fenton催化氧化亚甲基蓝（MB）.扫描电镜、透射电镜和光电子能谱分析表明,催化活性粒子（Feⁿ⁺/铁氧化物）成功负载在GO表面.实验研究了pH值、H₂O₂初始浓度、催化剂投加量等因素对MB降解效果的影响.结果表明,H₂O₂、MFGO和H₂O₂+MFGO体系在反应120min后,MB降解率分别达到7.83%、25.58%和99.19%;在优化条件为H₂O₂浓度0.79mol/L、MFGO用量0.75g/L、pH值8时,MB降解率可达99.90%;在pH值为3~11范围内,MB降解率均在99%以上;MFGO经过6次重复使用后对MB的降解率仍可达到95.08%,是一种pH值响应宽、可磁分离回收的新型非均相催化剂.     

南昌市生活垃圾卫生填埋生命周期评价

卫生填埋法是当前我国处理城市生活垃圾的主要方式,依据生命周期评价理论及分析框架,借助eFootprint软件对南昌市卫生填埋法处理城市生活垃圾进行生命周期分析以期找出各处理过程的突出环境影响及原因并提出针对性改善建议.结果表明：卫生填埋法处理城市生活垃圾的主要环境影响类型为全球变暖（GWP）、初级能源消耗（PED）、水资源消耗（WU）、酸化（AP）、光化学臭氧合成（POFP）、生态毒性（ET）、淡水富营养化（FEP）;电力盈余作为副产品参与分配使得各环境影响类型指标潜值减小,其中最突出的是PED,其次是WU;收集运输过程最突出的环境影响类型为POFP,其次依次为ET、PED、FEP,该过程应减少柴油运输车使用,适量引用节能环保或清洁能源汽车;卫生填埋过程在垃圾处理各过程中产生的环境污染最大,该过程最突出的环境问题是AP,其次是GWP,再者是PED、FEP、ET,该过程应改善工艺以提升填埋气收集效率,采用清洁能源减少柴油使用;填埋气发电过程因填埋气发电产生盈余电力,实现能量回收后对环境的正效益,该过程应提升填埋气收集以及燃烧发电效率;渗滤液处理过程的环境影响较小,主要表现为WU和FED,需在注重节能的同时优化升级处理工艺,改善当前处置工艺存在的弊端并排除隐患.     

内嵌POT损失分布拟合模型的风暴潮灾害风险价值测算

近年来,全球气候的异常变化导致风暴潮灾害频发,给我国造成了巨大灾害性损失。科学测算风暴潮灾害的风险价值,对于度量风暴潮灾害风险、估计风暴潮灾害损失、指导灾害风险有效分散具有重要意义。针对中国风暴潮灾害损失数据鲜明的频率低、厚尾性特征,本文引入极值理论的POT模型完成风暴潮灾害直接经济损失分布拟合,测算出不同置信水平下的风险价值,并通过了Kupiec失败频率检验。研究表明,运用POT模型测算不同置信水平下的风险价值可以作为今后中国风暴潮灾害风险科学度量以及单次灾害最大可能损失合理估计的基础。     

降水稳定同位素比率时间变化的iAWBM模拟

进行降水中稳定同位素比率时间变化的i AWBM模拟和比较,有助于评估模式在不同区域的适用性,改善对水循环过程中水稳定同位素变化规律的认识.本文利用i AWBM的模拟数据,分析了GNIP代表站降水中δ18O的时间变化特征、降水中δ18O与温度和降水量之间的关系、区域大气水线,并将模拟结果与实测结果进行了比较.结果表明,9个GNIP代表站的降水同位素在不同季节的变化特点均能被模拟出;各代表站模拟与实测的降水同位素长时间序列之间的相关系数达到显著的信度(p0.001),均方根误差在一个合理的估计范围;i AWBM很好地再现了出现在维也纳、雅库茨克和渥太华站的显著温度效应,出现在香港、波哥大、昆明、哈拉雷和拉罗汤加岛站的降水量效应,以及出现在曼谷站的温度效应和降水量效应共存的特点;模拟的不同气候条件下的区域大气水线与实际大气水线相近.说明i AWBM具有模拟不同气候区降水中稳定同位素时间变化的能力.     

蚯蚓对城市污泥蚯蚓堆肥过程中微生物特征变化的影响

为揭示蚯蚓对城市污泥中微生物特征的影响和作用,本研究采用赤子爱胜蚓处理城市污泥,以无蚯蚓处理为对照,探讨蚯蚓对污泥堆肥中微生物数量、活性和种群变化的影响.结果显示:蚯蚓在前期能够显著提升脱氢酶的活性和细菌16S r DNA的丰度;从而加速有机物的降解,促进后期堆肥产物的腐殖质化.高通量测序结果表明:从60 d开始,蚯蚓组和对照组的细菌种群结构出现明显差异,蚯蚓处理能够显著增加最终产物的细菌种群的Chao1和Shannon指数.最终产物中,对照组的优势菌群为变形菌门(56%)、拟杆菌门(16.3%)和厚壁菌门(15.4%);蚯蚓组的优势种群有变形菌门(31.3%)、拟杆菌门(27.1%)、放线菌门(21.1%).与对照组相比,蚯蚓粪中放线菌和根瘤菌的丰度分别提高了13.1%和2.5%,表明蚯蚓的作用提升了堆肥产物作为微生物肥料的潜力.     

复合有机污染物在含水层介质表面的吸附性能

为明确氯代烃芳香烃类复合污染物在含水层介质上的吸附特性,选取甲苯、苯、1,2-二氯丙烷,1,2,3-三氯丙烷（TCP）作为典型污染物开展吸附试验,结果表明吸附过程符合Henry线性模型,分配系数K_p值分别为0.38,0.41,0.73,1.00kg/L,污染物在细砂上的吸附强度顺序为甲苯>苯> 1,2-二氯丙烷> TCP;竞争吸附试验结果表明,苯可以明显促进甲苯在细砂介质上的吸附,而甲苯抑制了苯的吸附;1,2-二氯丙烷抑制TCP在细砂介质上的吸附,而TCP对1,2-二氯丙烷的吸附影响并不明显.TCP在含水层介质上的吸附量随甲苯浓度增加而增大;当甲苯初始浓度<2mg/L时,TCP对于甲苯在含水层介质上的吸附起促进作用,当甲苯的初始浓度³2mg/L时,TCP对于其在含水层介质上的吸附起抑制作用.     

Study on the effects of organic matter characteristics on the residual aluminum and flocs in coagulation processes

Characteristics of organic matter may affect the residual aluminum after the coagulation process. This study reported the results of a survey for one drinking water treatment plant and measured the concentration of residual aluminum species with different molecular weights.Survey results indicated that humic acid or organic matter whose molecular weight was smaller than 1500 Da had significant effects on residual aluminum. All the treatment processes were ineffective in removing dissolved organic matter whose molecular weight was smaller than1500 Da. These results also indicated that the addition of sand or polyacrylamide in the coagulation process could greatly decrease the concentration of humic acid, and the concentration of residual aluminum also decreased. These results revealed that for all water samples after filtration, the majority of total residual aluminum existed in the form of total dissolved aluminum, accounting for 70%–90%. The concentration of residual aluminum produced in bovine serum albumin solutions indicated that when the DOC was larger than4.0 mg/L, there were still significant differences when the solution p H value varied from 4.0 to 9.0.     

Effects of chlortetracycline, Cu and their combination on the performance and microbial community dynamics in swine manure anaerobic digestion

Swine manure was typical for the combined pollution of heavy metals and antibiotics. The effects of widely used veterinary antibiotic chlortetracycline(CTC), Cu and their combination on swine manure anaerobic digestion performance and microbial community have never been investigated. Thus, four 2 L anaerobic digestion reactors were established including reactor A(control), B(CTC spiked by 0.5 g/kg dry weight, dw), C(Cu spiked by 5 g/kg dw) and D(combination of CTC, 0.5 g/kg dw, and Cu, 5 g/kg dw), and dynamics of bacterial and archaeal community structure was investigated using high throughput sequencing method. Results showed that addition of CTC and Cu separately could increase the total biogas production by21.6% and 15.8%, respectively, while combination of CTC and Cu severely inhibited anaerobic digestion(by 30.3%). Furthermore, corresponding to different stages and reactors, four kinds of microbes including bacteria and archaea were described in detail, and the effects of CTC, Cu and their combination mainly occurred at hydrolysis and acidification phases. The addition of Cu alone changed the dynamics of archaeal community significantly. It was genus Methanomassiliicoccus that dominated at the active methane production for A, B and D, while it was genus Methanobrevibacter and Methanoculleus for C.     

Baosteel emission control significantly benefited air quality in Shanghai

As the largest iron and steel producer in China, a part of Baosteel moved out of Shanghai deserves close attention due to its environmental impact. To understand the effect of Baosteel emission control on air quality in Shanghai, daily PM_(10), PM_(2.5), SO_2, NO_2 and CO were measured from 2010 to 2016. Concentrations of pollutants in Baoshan District presented a decreased trend during 2010–2016, with a reduction rate of 28.6% for PM_(10), 67.3% for SO_2, 8.6% for NO_2 and 42.0% for CO. However, fine particle pollution in Baoshan District during 2012–2016 seems to become more prominent, with PM_(2.5) concentration of 47 ± 28,45 ± 33, 38 ± 24, 54 ± 41 and 51 ± 34 μg/m3, respectively, indicating a slight increase of 8.5%in PM_(2.5). Concentrations of PM_(10) and CO decreased by 12.5% and 33.8% in the second half year in 2016(compared with that in 2015) probably due to closure of blast furnace of Baosteel. Baosteel was identified as the largest pollution source in Baoshan District.Emission from Baosteel accounted for 58.0% of SO_2, 43.6% of NO_2 and 79.3% of dust in total emission from Baoshan District during 2010–2015. Meanwhile, pollutant emission and coal consumption from Baosteel decreased by 52.0% for SO_2, 40.1% for NO_2, 15.7% for dust and22% for coal consumption. Energy consumption in Baoshan District reduced by 31% from2011 to 2015. Air quality improvement in Shanghai was attributed to local emission reduction, together with regional air quality improvement.