类氧化硅气凝胶吸附材料的制备及其吸附性能

以有机硅高沸物和Na₂SiO₃·9H₂O为原料,采用溶胶-凝胶法制备出疏水性的类氧化硅气凝胶吸附材料。采用透射电子显微镜、傅里叶变换红外分析仪和比表面与空隙度分析仪对该吸附材料的结构进行表征。表征结果显示,该吸附材料呈海绵状多孔结构,比表面积为294.48 m²/g,孔径分布较宽（为2 ~140 nm）,平均孔径为8.95 nm。实验结果表明：采用该吸附材料常温下静态吸附处理质量浓度为10 mg/L的罗丹明B（RhB）溶液,在类氧化硅气凝胶吸附材料加入量50 g/L、静态吸附时间5 h的最佳静态吸附工艺条件下,RhB去除率为98.8%,吸附后RhB质量浓度为0.124 mg/L;采用该吸附材料常温下动态吸附处理质量浓度为15 mg/L的RhB溶液,吸附4 h后开始穿透,吸附7 h后完全穿透。穿透时间较长,表明该吸附材料具有较大的吸附容量。     

Estimation methods and monitoring network issues in the quantitative estimation of land-based COD and TN loads entering the sea: a case study in Qingdao City,China

At present, the monitoring network of China cannot provide sufficient data to estimate land-based pollutant loads that enter the sea, and estimation methods are imprecisely used. In this study, the selection of monitoring stations, monitoring frequency, and pollutant load estimation methods was studied in Qingdao City, a typical coastal city in China, taken as an example. Land-based pollutant loads from Qingdao were estimated, and load distribution, density, and composition were analyzed to identify the key pollution source regions (SRs) that need to be monitored and controlled. Results show that the administrative land area of Qingdao can be divided into 25 sea-sink source regions (SSRs). A total of 14 more rivers and 62 industrial enterprises should be monitored to determine the comprehensive pollutant loads of the city. Furthermore, the monitoring frequency of rivers should not be less than three times/year; a monitoring frequency of five or more times is preferable. The findings on pollutant load estimation with the use of different estimation methods substantially vary; estimation results with the use of ratio-based methods were 10 and 22 % higher than those with the use of monitoring-based methods in terms of chemical oxygen demand (COD) and total nitrogen (TN), respectively. None-point sources contributed the majority of the pollutant loads at about 70 % of the total COD and 60 % of the total TN.     

CuO/γ-Al_2O_3类Fenton试剂降解丁基黄药

CuO/γ-Al2O3类Fenton试剂是降解丁基黄药的优良试剂。该试剂与传统的Fenton试剂相比,提高了反应的pH值,可在较高pH（4~5）条件下反应,而传统的Fenton试剂的适宜pH值一般在3以下。采用单因素实验和正交实验相结合的方法研究了pH、催化剂投加量、过氧化氢投加量以及反应时间对丁基黄药降解效果的影响,并对催化剂的使用寿命进行了探讨。研究结果表明,反应的最佳条件为：pH为4~5,催化剂投加量为6 g/L,过氧化氢用量为30 mg/L,反应30min。在此反应条件下,丁基黄药的降解率达98%以上;影响丁基黄药降解效果的因素大小顺序为：pH〉反应时间〉H2O2用量〉催化剂投加量,其中pH对CuO/γ-Al2O3类Fenton试剂降解丁基黄药的影响最为显著。     

热解吸对污染土壤中不同形态汞的去除作用

选取贵州省万山矿区的汞污染土壤样品进行不同形态汞的热解吸去除行为研究。研究了热解吸过程中∑Hg的去除效果及动力学,以及温度和时间对污染土壤中不同形态汞的去除作用。结果表明,热解吸修复技术可有效去除土壤中的汞,土壤中∑Hg的热解吸过程符合二级动力学方程。固定热解吸时间在10 min时,随着热解吸温度的升高,土壤中水溶态汞、盐酸溶态汞和碱溶态汞含量呈现先下降后上升再下降的趋势,王水溶汞和盐酸溶态汞始终呈现下降趋势,说明不同形态的汞之间发生了转化。热解吸温度为250℃时,随着热解吸时间的增加,环境风险大的水溶态汞、盐酸溶态汞、碱溶态汞和硝酸溶态汞的去除率大幅增加,土壤的有机质损失较少,说明在低温下,延长热解吸时间,对生物毒性强的形态汞有良好的修复效果,且此温度下处理后的土壤更容易恢复农田耕作。     

初始温度对人粪便好氧堆肥过程的影响

温度是好氧堆肥过程中需要控制的一个重要因素。不同的初始温度直接影响了堆肥过程中微生物活性及有机物的降解。为了研究初始温度对粪便好氧堆肥过程的影响,采用序批式好氧堆肥反应器,以新鲜锯末为载体,控制含水率在55%~60%的范围左右并强制通风的好氧条件下,进行了初始温度分别为25、35、45和55℃,20 d为一个周期好氧堆肥实验,研究了不同初始温度条件下堆肥过程有机物降解、氮的迁移转化及种子发芽指数的变化。结果表明,初始的高温度会抑制堆肥反应的进行,但初始温度越高,水解效果越显著;初始的高温有利于COD的去除,最终COD的去除率分别为88.2%、89.3%、92.0%和89.9%。初始高温对种子发芽率有抑制作用,同时延迟了堆肥的腐熟期。     

高温滤袋的有效清灰强度

对Φ120 mm×1 000 mm氟美斯滤袋的最大侧壁压力峰值、除尘器运行阻力进行实验测试,并结合滤袋破损情况探究高温滤袋的有效清灰强度。结果表明,最大侧壁压力峰值在一定范围内对滤袋有较好的清灰效果且对滤袋的损伤较小。对粉煤灰而言,滤袋沿长度方向的平均最大侧壁压力峰值为876 Pa时的强度能满足除尘器的清灰要求,随着滤袋的最大侧壁压力峰值增大,除尘器清灰效果越好,当平均最大侧壁压力峰值超过2 713 Pa时,清灰效果仅轻微提升;且局部最大侧壁压力峰值大于5 282 Pa时滤袋破损,造成过度清灰。     

基于DO控制实现SBR短程硝化过程

采用序批式反应器(SBR)处理模拟氨氮废水,研究了固定供氧模式下氨氮降解过程和溶解氧变化规律,并对DO控制实现短程硝化机理进行了探讨.实验结果表明,当DO＜1 mg/L时,体系产生亚硝酸盐积累,当亚硝化反应结束后,DO出现跃升现象,并且pH值对短程硝化有一定影响,充足的碱度和较高的pH值有利于建立以DO为控制参数实现短程硝化过程控制.短程硝化启动后,亚硝酸盐积累率达90％以上,并且经过度曝气5d后,系统仍保持稳定运行.     

SMBBR预处理发酵类制药废水

采用高活性反硝化菌DNF409作为菌种,以SDC-03型生物载体作为填料,通过特异性移动床生物膜反应器预处理发酵类制药废水。实验结果表明:在反应温度为22~26℃、DO为2~4 mg/L、污泥质量浓度为2 000 mg/L、水力停留时间为16 h的条件下,COD,NH3-N,TN,TP的平均去除率分别为72.45%,27.72%,18.54%,84.58%,BOD5/COD由0.17提高到0.38,废水的可生化性得到提高;出水经后续生化处理达到GB 21903—2008《发酵类制药工业水污染物排放标准》的排放要求。     

Toxic effects of chlorpyrifos on lysozyme activities,the contents of complement C3 and IgM,and IgM and complement C3 expressions in common carp (Cyprinus carpio L.)

Chlorpyrifos is one of the organophosphate pesticides widely used in agricultural practices throughout world. It has resulted in a series of toxicological and environmental problems, such as impacts on many non-target aquatic species, including fish. In the present study, toxic effects of chlorpyrifos on lysozyme activities, contents of IgM and complement C3, and the expressions of IgM and complement C3 at mRNA level in common carp were evaluated by acute exposure of 15 (1/10 LC₅₀) or 75 μg L⁻¹ (1/2 LC₅₀) of chlorpyrifos for 7 d. The results of acute toxicity tests showed that the 96 h-LC₅₀ of chlorpyrifos for common carp was determined to be 149 μg L⁻¹. We also found that chlorpyrifos promoted lysozyme activities at the earlier stages of exposure but inhibited it at the late stages in the serum, hepatopancreas, and spleen of common carp. Furthermore, it was observed that chlorpyrifos-exposure decreased IgM contents in fish serum and spleen while increased it in kidney. No obvious change was found in the contents of complement C3 in fish spleen, while a slight increase of complement C3 was observed in fish serum and kidney after 1 d of chlorpyrifos-exposure. In addition, the results of quantitative real-time PCR showed that IgM and complement C3 expressions were up-regulated at the earlier stage of exposure but down-regulated at later stage. Our results indicate that chlorpyrifos causes immunotoxicity to common carp.