入冬水生高等植物的衰亡对河流水质的影响

上海市郊河流水体中有很高的氮、磷和有机负菏，由于受水生高等植物生灭的影响，初春河流中的氮、磷和有机负菏明显高于上一年的初冬，河流中的水生高等植物能大量地吸收水体中的氮、磷，抑制藻类生长，净化水质；但其植株残体在水中的腐解，又会重新释出营养元素，造成对水体的二次污染。在冬季，随着水生高等植物的大量死亡这种污染更加明显，应加强对水生高等植物的利用，尝试建立既能净化水质，又有创造经济效益的生态工程模式，使市郊受污水体得到资源化利用。     

活性炭性质对其吸附水中硝基苯性能的影响

通过对活性炭进行HNO3氧化及热处理改性,研究了活性炭性质对其吸附硝基苯性能的影响.以低温液氮(N2/77 K)吸附测定活性炭的比表面积和孔容、孔径分布;以Boehm滴定、零电荷点pHPZC的测定及元素分析定量表征活性发表面含氧官能团变化.结果表明:经改性后,活性炭比表面积及总孔容略有减小,表面性质发生较大变化.改性活性炭对硝基苯的吸附容量明显改变,吸附容量大小依次为:AC1′＞AC0′＞AC0＞AC1.经硝酸氧化后,比表面积下降、存在过多表面含氧官能团是导致AC1吸附硝基苯能力降低的主要原因;而AC1'表面适量酚羟基所提供的氢键吸附是其对硝基苯吸附量增加的主要原因.     

Climate Change and Energy Technologies

The long time scale of the climate change problem and the inherent nature of the carbon cycle bring important implications for present technology development efforts. Even if major technology improvements are achieved for non-carbon-emitting technologies such as energy-intensity improvements, wind, solar, biomass, and nuclear over the course of the 21^st century, most examinations of potential future greenhouse emissions conclude that additional technology development will be required to stabilize greenhouse gas concentrations. The evelopment of an expanded suite of technologies including carbon capture and disposal, hydrogen systems and biotechnology hold the potential to dramatically reduce the cost of stabilizing greenhouse gas concentrations. This paper examines these technologies in the context of a global integrated assessment model of energy, agriculture, land-use, economics, and carbon cycle processes.     

水量衡算条件下人工湿地对有机物的去除研究

构建了芦苇和无植物2种人工湿地，在系统水量衡算的基础上比较了2种湿地对生活污水中有机物的去除效果。结果证明，在植物收割后的冬季，芦苇湿地对有机物的去除率低于无植物湿地系统约2％；在其他季节，芦苇湿地对污水CODcr的去除率比无植物湿地高出3.3％-5％。但对BOD5的去除率却比无植物湿地低了1.9％-2.7％。因此，芦苇湿地对有机物的去除效果比无植物湿地高，但提高不多。比较了2种系统的氧化还原电位，芦苇湿地比无植物湿地的高（P〈0.05），这种提高主要集中在湿地水面以下约10cm的深度；从整个湿地床体来看。2块连续运行的潜流水平湿地内部氧化还原状态大部分相同。主要是厌氧状态。比较了2种人工湿地基质中降解有机物的细菌，放线菌和真菌的数量，二者没有明显的差别。考察了湿地进水有机负荷与去除量的关系，二者呈现显著的线性相关性（R^2〉0.99）。     

水解酸化-好氧工艺处理感光材料有机废水研究

感光材料有机生产废水含有多种合成有机物，其BOD5／CODer比值为0．46～0．48，可生化性良好，经水解酸化处理后该废水的BOD5／CODcr的比值可提高至0．54～056，平均增加了17％左右。水解酸化－好氧串联工艺对该废水总的处理效果表明：在废水CODer进水浓度2000～2500mg／L范围内，CODer总去除率可达95％左右，BOD5总去除率可达97％左右；水解酸化后好氧生化系统的动力学半速度常数Ks＝103mg／L，最大比降解速度K＝5．0／日。     

腕足类生物壳体在沉积、成岩过程中同位素平衡问题研究

综合分析了现代腕足类生物壳体方解石中的C、O同位素特征，以及有关古生代腕足类生物壳体方解石构造和地球化学研究成果，分析结果证明：只有那些无发光性特点、无胶结和溶蚀构造特点、有较好纤维构造特点、含高Sr、Na和低Mn、Fe（Mg）的第二层腕足类生物壳体方解石的δ18O值不受成岩作用影响；而原始层和壳体中的特殊部位如铰合轴、腕骨、茎孔、交互面、肌痕等在沉积、成岩过程中与海水处于非同位素平衡状态。     

强化混凝去除黄浦江水有机物的试验研究

强化混凝去除有机物的效果与水源的分子量分布特性有着密切的关系.由于黄浦江水中低分子量的溶解性有机物占多数,因此,强化混凝处理有机物效果有限.对于＜1k分子量区间的有机物.增加混凝剂投量可有效去除紫外吸光值(UV254),但去除溶解性有机碳(DOC)的效果很差.尽管增加混凝剂投量和降低pH都能有效地去除有机物,但决定强化混凝效果的主要因素是pH,去除黄浦江水有机物的最佳pH范围为6～5.     

典型北方高碱度微污染水体强化混凝的示范研究

以高碱度、受有机物污染的典型北方水体为例,探索适宜的强化混凝技术.在水质调查的基础上,提出适合水质特征的强化混凝目标.研究了高碱度水体强化混凝技术方法.研究表明,可以通过3条技术途径提高水体中有机物的去除效率.其一在混凝前优化pH,促进絮凝剂水解形成中聚体,AlCl3在pH 6左右,FeCl3在pH 5左右时,有机物去除率可以提高一倍左右;其二是强化沉淀软化;其三是絮凝剂优化.结合我国实际情况,通过对传统絮凝剂进行改性,研制出了适合我国北方水质特征的高效絮凝剂,能较传统絮凝剂将有机物去除率提高30%以上.     

Simultaneous determination of dissolved organic nitrogen, nitrite, nitrate and ammonia using size exclusion chromatography coupled with nitrogen detector

Accurate quantification of dissolved organic nitrogen (DON) has been a challenge due to the cumulative analytical errors in the conventional method via subtracting dissolved inorganic nitrogen species (DIN) from total dissolved nitrogen (TDN). Size exclusion chromatography coupled with an organic nitrogen detector (SEC-OND) has been developed as a direct method for quantification and characterization of DON. However, the applications of SEC-OND method still subject to poor separations between DON and DIN species and unsatisfied N recoveries of macromolecules. In this study, we packed a series of SEC columns with different lengths and resin materials for separation of different N species and designed an independent vacuum ultraviolet (VUV) oxidation device for complete oxidation converting N species to nitrate. To guarantee sufficient N recoveries, the operation conditions were optimized as oxidation time ≥ 30 min, injection mass (sample concentration × injection volume) < 1000 µL × mg-N/L for macromolecular proteins, and neutral pH mobile eluent. The dissolved O₂ concentration in SEC mobile phase determined the upper limit of VUV oxidation at a specific oxidation time. Compared to conventional HW50S column (20 × 250 mm), HW40S column (20 × 350 mm) with mobile phase comprising of 1.5 g/L Na₂HPO₄·2H₂O + 2.5 g/L KH₂PO₄ (pH = 6.85) could achieve a better separation of DON, nitrite, nitrate, and ammonia. When applied to river water, lake water, wastewater effluent, groundwater, and landfill leachate, the SEC-OND method could quantify DON as well as DIN species accurately and conveniently even the DIN/TDN ratio reached 0.98.     

Insights into reactive oxygen species formation induced by water-soluble organic compounds and transition metals using spectroscopic method

Ambient particulate matter (PM) can cause adverse health effects via their ability to produce Reactive Oxygen Species (ROS). Water-Soluble Organic Compounds (WSOCs), a complex mixture of organic compounds which usually coexist with Transition Metals (TMs) in PM, have been found to contribute to ROS formation. However, the interaction between WSOCs and TMs and its effect on ROS generation are still unknown. In this study, we examined the ROS concentrations of V, Zn, Suwannee River Fulvic Acid (SRFA), Suwannee River Humic Acid (SRHA) and the mixtures of V/Zn and SRFA/SRHA by using a cell-free 2′,7′-Dichlorodihydrofluorescein (DCFH) assay. The results showed that V or Zn synergistically promoted ROS generated by SRFA, but had an antagonistic effect on ROS generated by SRHA. Fluorescence quenching experiments indicated that V and Zn were more prone to form stable complexes with aromatic humic acid-like component (C1) and fulvic acid-like component (C3) in SRFA and SRHA. Results suggested that the underlying mechanism involving the fulvic acid-like component in SRFA more tending to complex with TMs to facilitate ROS generation through π electron transfer. Our work showed that the complexing ability and complexing stability of atmospheric PM organics with metals could significantly affect ROS generation. It is recommended that the research deploying multiple analytical methods to quantify the impact of PM components on public health and environment is needed in the future.