不同底物驯化氧化亚铁硫杆菌的差异及对煤炭生物脱硫效率的影响

分别以FeS2和FeSO4为底物培养驯化嗜酸性氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans)LX5,结果发现以FeS2为底物驯化A.ferrooxidans LX5,在培养20 d时,培养液中LX5的菌体数量达3.0×107个/mL,对FeS2中亚铁及还原性硫的氧化能力均较强.A.fer...     

胞外聚合物与溶解性微生物产物的关系

通过活性污泥内源呼吸试验,发现胞外聚合物与溶解性微生物产物之间存在相互转化、吸附与被吸附的关系。内源呼吸初期(0~19h),bound EPS水解生成BAP,细胞自溶过程也释放部分SMP。19~43h,微生物利用SMP中易降解部分生成bound EPS和UAP,大分子量的SMP被bound EPS吸附,并存在一定程度的细胞水解。43~162h为SMP分泌、溶出阶段,内源呼吸加强,微生物脱氢酶活性几乎丧失,细胞水解、自溶。bound EPS表面出现SMP解吸-吸附的交替过程。162~210h期间bound EPS水解及细胞自溶为主要过程。并且产出的SMP可生物降解性较差,对微生物表现出毒性作用,抑制其脱氢酶活性,而在毒性环境下,微生物又产出更多的SMP。     

国外城市垃圾焚烧排放物标准比较

本文综述了国外几个发达国家及公司在城市垃圾焚烧技术中污染物排放的一些标准，可以为国内在设计城市垃圾处理厂及垃圾焚烧炉时提供有益的借鉴。     

污泥胞外聚合物的提取方法及其对污泥脱水性能的影响

采用7种不同方法提取污泥胞外聚合物(EPS),并研究污泥不同层EPS剥离前后对污泥脱水性能的影响.结果表明,甲醛+NaOH和2%EDTA提取法对污泥中紧密结合的胞外聚合物(tightly bound extracellular polymeric substances,TB-EPS)提取效率最高,总固体(SS)中的EPS提取量分别为128.9 mg.g-1和42.38 mg.g-1,但提取后细胞破裂严重,不能代表污泥EPS的真实含量,不宜采用.加热法较为温和,提取效率较高,总SS中EPS产量为21.97 mg.g-1.污泥剥离黏液层(Slime层)、松散结合的胞外聚合物(loosely bound extracellular polymeric substances,LB-EPS)和TB-EPS层后污泥的脱水性能大幅度改善,其中Slime层EPS含量越高污泥的脱水性能越差,当污泥EPS大量地释放到溶液中即Slime层时污泥的CST值大幅度升高,污泥的脱水性能变差.石湖墟和昂船舟污泥初始的毛细吸水时间(CST)为132.9 s和229.9 s,当剥离Slime层时这2种污泥的CST值分别为80.8 s和79.4 s,脱水性能得到明显改善.     

不同碳氮比对海水养殖废水脱氮效果的影响

工厂化海水养殖废水C/N（碳氮比）较低,有效碳源不足,生物脱氮工艺往往由于缺乏碳源而受到抑制.为揭示脱氮工艺中不同过程对碳源匮乏的敏感程度,应用A/O-MBBR（缺氧/好氧-移动床生物膜反应器）处理模拟海水养殖废水,探讨进水C/N降低（从12降至1）对反应器运行效果的影响,并根据EPS（胞外聚合物）、AMO（氨单加氧酶）、NOR（亚硝酸盐氧化酶）、NIR（亚硝酸盐还原酶）、NR（硝酸盐还原酶）的活性,分析碳源不足对不同脱氮过程的抑制状况.结果表明:①C/N降低时,COD_Cr、NH₄+-N、NO₂--N的去除率均未下降,自养型的氨氧化、亚硝化过程不受影响,AMO和NOR活性提高.②缺氧区pH降低,ρ（DO）升高,NO₃--N的去除率显著降低,C/N为5时开始积累,NR活性明显下降.③异养反硝化反应电子供体出现由外碳源向内碳源和EPS的转换,缺氧区EPS含量逐渐减少,C/N为1时比C/N为6时减少了47%.研究显示,碳源不足是造成海水养殖废水生物反硝化不彻底的主要原因,为了实现高效脱氮,需要在海水养殖废水处理过程中严格控制ρ（DO）并且提供足够的碳源.      

生物滴滤塔对疏水性VOCs气体的去除及其生物膜特性研究

利用正己烷降解菌Pseudomonas mendocina NX-1和二氯甲烷（DCM）降解菌Methylobacterium rhodesianum H13强化生物滴滤塔（BTF）同时净化不同疏水性的正己烷和DCM混合废气,研究了挂膜启动阶段及稳定运行阶段BTF对污染物的去除性能与限制因素及生物膜相的特性变化.结果表明,在正己烷和DCM浓度均为100 mg·m^-3,停留时间（EBRT）为60 s的条件下,运行25 d即可完成BTF的启动,正己烷和DCM的去除率分别可达到65%和100%.系统稳定运行时,正己烷和DCM的最大去除负荷分别为16.1 g·m^-3·h^-1和92.0 g·m^-3·h^-1.正己烷和DCM的去除过程分别受到传质限制与反应限制影响.BTF稳定运行后,塔内生物膜胞外聚合物（EPS）中蛋白质（PN）含量逐渐增加至启动时的2.7倍,蛋白质与多糖的比值（PN/PS）从0.28增加至0.96.生物膜表面相对疏水性从21%增加至66%,Zeta电位从-12.7 mV降低至-9.2 mV.压降的模拟结果与实验数据良好拟合（R²>0.96）.     

Source apportionment of perfluoroalkyl substances in surface sediments from lakes in Jiangsu Province, China: Comparison of three receptor models

Receptor models have been proved as useful tools to identify source categories and quantitatively calculate the contributions of extracted sources.In this study,sixty surface sediment samples were collected from fourteen lakes in Jiangsu Province,China.The total concentrations of C_4–C_(14)-perfluoroalkyl carboxylic acids and perfluorooctane sulfonic acid(∑_(12)PFASs) in sediments ranged from 0.264 to 4.44 ng/g dw(dry weight),with an average of 1.76 ng/g dw.Three commonly-applied receptor models,namely principal component analysis-multiple linear regression(PCA-MLR),positive matrix factorization(PMF) and Unmix models,were employed to apportion PFAS sources in sediments.Overall,these three models all could well track the ∑_(12) PFASs concentrations as well as the concentrations explained in sediments.These three models identified consistently four PFAS sources:the textile treatment sources,the fluoropolymer processing aid/fluororesin coating sources,the textile treatment/metal plating sources and the precious metal sources,contributing 28.1%,37.0%,29.7% and 5.3% by PCA-MLR model,30.60%,39.3%,22.4% and 7.7% by PMF model,and 20.6%,52.4%,20.2% and 6.8% by Unmix model to the ∑_(12) PFASs,respectively.Comparative statistics of multiple analytical methods could minimize individual-method weaknesses and provide convergent results to enhance the persuasiveness of the conclusions.The findings could give us a better knowledge of PFAS sources in aquatic environments.     

胞外聚合物对活性污泥吸附去除全氟辛烷磺酸（PFOS）的影响

采用活性污泥和去除胞外聚合物(EPS)污泥作为吸附剂,探讨污泥吸附PFOS的机制和EPS在吸附过程中的作用.结果表明,活性污泥和去除EPS污泥吸附PFOS均符合准二级动力学方程,平衡吸附量(q_e)分别为0.46 mg·g~(-1)和0.38 mg·g~(-1),化学吸附占主要作用.吸附等温线可以用Freundlich、Langmuir及Temkin方程拟合.Ca~(2+)和Cu~(2+)通过离子架桥作用促进PFOS在污泥上的吸附.活性污泥吸附去除PFOS的效果明显优于去除EPS后的污泥.傅里叶红外光谱(FTIR)和X射线光电发射光谱(XPS)分析吸附前后的污泥官能团变化,发现去除了EPS的污泥中羟基、羧基和氨基活性基团减少,而这些基团是PFOS吸附过程中参与反应的主要成分.由此可见污泥EPS中蛋白质含有的羧基和氨基活性基团为PFOS提供了吸附反应位点,EPS在吸附过程中起到至关重要的作用.     

The astysphere and urban geochemistry—a new approach to integrate urban systems into the geoscientific concept of spheres and a challenging concept of modern geochemistry supporting the sustainable development of planet earth

Background, aim, and scope  In 1875, the geoscientist Walter Suess introduced several spheres, such as the lithosphere and the atmosphere to promote a comprehensive understanding of the system earth. Since then, this idea became the dominating concept for the understanding of the distribution of chemical elements in the system earth. Meanwhile, due to the importance of human beings on global element fluxes, the term anthroposphere was introduced. Nevertheless, in face of the ongoing urbanization of the earth, this concept is not any more adequate enough to develop a comprehensive understanding of global element fluxes in and between solid, liquid, and gaseous phases. This article discusses a new concept integrating urbanization into the geoscientific concept of spheres. Main features  No geological exogenic force has altered the earth’s surface during the last centuries in such an extent as human activity. Humans have altered the morphology and element balances of the earth by establishing agrosystems first and urban systems later. Currently, urban systems happen to become the main regulators for fluxes of many elements on a global scale due to ongoing industrial and economic development and a growing number of inhabitants. Additionally, urban systems are constantly expanding and cover more and more former natural and agricultural areas. For nature, urban systems are new phenomena, which never existed in previous geological eras. The process of the globe’s urbanization concurrently is active with the global climate change. In fact, urban systems are a major emitter for climate active gases. Thus, beside the global changes in economy and society, urbanization is an important factor within the global change of nature as is already accepted for climate, ecosystems, and biodiversity. Results  Due to the fact that urbanization has become a global process shaping the earth and that the urban systems are globally cross-linked among each other, a new geoscientific sphere has to be introduced: the astysphere. This sphere comprises the parts of the earth influenced by urban systems. Accepting urbanization as global ongoing process forming the astysphere comprehensively copes with the growing importance of urbanization on the creation of present geologic formations. Discussion  Anthropogenic activities occur mainly in rural and urban environments. For long lasting periods of human history, human activities mainly were focused on hunting and agriculture, but since industrialization, urbanized areas became increasingly important for the material and energy fluxes of earth. Thus, it seems appropriate to classify the anthroposphere into an agriculturally and an urban-dominated sphere, which are the agrosphere (Krishna 2003) and the astysphere (introduced by Norra 2007). Conclusions  We have to realize that urban systems are deposits, consumers, and transformers of resources interacting among each other and forming a network around the globe. Since the future of human mankind depends on the sustainable use of available resources, only a global and holistic view of the cross-linked urban systems forming together the astysphere provide the necessary geoscientific background understanding for global urban material and energy fluxes. If we want to ensure worth-living conditions for future generations of mankind, we have to develop global models of the future needs for resources by the global metasystem of urban systems, called astysphere. Perspectives  The final vision for geoscientific research on the astysphere must be to design models describing the global process of urbanization of the earth and the development of the astysphere with respect to fluxes of materials, elements, and energy as well as with respect to the forming of the earth’s face. Besides that, just from the viewpoint of fundamental research, the geoscientific concept of spheres has to be complemented by the astysphere if this concept shall fully represent the system earth.

大孔网状树脂在富集水体中有机物的应用

介绍了ＸＡＤ及ＧＤＸ型大孔网状树脂富集水体中痕量有机物的方法。讨论了上述树脂对某些有机物的富集率；影响树脂对有机污染物富集率的因素，如洗脱剂的种类，水样流速，水样和洗脱液保存时间及有机物性质等因素的影响。提出了富集过程中应注意的问题。