TVS／TFS去除率在ATAD污泥稳定评价的应用

在ATAD(Autothermal Thermophilic Aerobic Digestion,自升温高温好氧消化)工艺污泥稳定评价中引入TFS．提出“TVS/ TFS去除率”的概念,得出“TVS/TFS去除率”可以代替“VS(g)去除率”而成为一种新的污泥稳定指标的结论;采用数学微分的方法分析了“TVS/TFS去除率”和“VS(g)去除率”的数据误差问题,进泥TS为60g/L,TVS/TS为56％的运行条件下,前者的最大数据误差仅为3．16％,远小于后者的误差最大值15．45％,即引入TFS解决了“VS(g)去除率”数据波动大的问题;TFS的引入还节约了污泥稳定研究所需的时间和工作量。     

Effects of Poly(Ethylene Glycol) on the Production of Poly(β-Hydroxybutyrate) by Azotobacter vinelandii UWD

gt;Azotobacter vinelandii UWDgt;, ATCC 53799, an engineered strain derived from gt;Azotobacter vinelandii UWgt; was used in the poly(ethylene glycol) (PEG)-modulated synthesis of poly(g src="/content/m02g770820837260/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-hydroxybutyrate) (PHB). To the best of our knowledge, this is the first report on modulating the production of PHB by amending the fermentation broth with PEG using gt;A. vinelandii UWDgt;. It was determined that gt;A. vinelandii UWDgt; is prone to back-mutation to the parent strain; hence fermentation experiments require the use of the antibiotic rifampicin. Diethylene glycol (DEG) and PEGs with molecular weights of 400, 2000, and 3400 Da and pentaerythritol ethoxylate (PEE) were used in the modulated fermentation experiments in a concentration of 2% (w/v). The molecular weight of the resulting polymers was reduced by up to 78%. No impact on the productivity of the strain was observed. Spectroscopic evidence showed that PEG-modulated synthesis resulted in the covalent attachment of the ethylene glycol moiety only when a small molecule, DEG, was used. PEGs had the same effects on the polymer formation in terms of molecular weight reduction as DEG, but no spectroscopic evidence was found for the formation of a covalent linkage between PHB and higher molecular weight PEGs.     

"一退两还"中的博弈分析与制度创新

“一退两还”即“退耕还林还草”，是我国政府在世纪之交所作出的一项旨在推进国民经济可持续发展的战略举措。本文运用博弈论的方法，通过对“一退两还”中的各个相关主体利益的思考和行为的辨析，结合分析结论，提出了对提高“一退两还”实施效果具有重要意义的制度创新思路。     

味精浓废水生物处理优化工艺

本文阐述两相厌氧消化法与缺氧—厌氧消化法处理味精浓废水的比较试验.进水为6×10~4mg/L～8×10~4mg/L时,两相厌氧消化法COD去除率为78%,产气率为0.15m~3/kgCOD,CH_4含量为50%.缺氧—厌氧消化法COD去除率为82.2%,产气率为0.23m~3/kgCOD,CH.含量达65%.两种方法均可使出水pH值由3.2上升至7.0以上.氯离子和氨氮的去除不明显.综合上述结果与运行管理的稳定程度均是缺氧——厌氧消化法优于两相厌氧消化法.     

Sorption of the natural endocrine disruptors,oestrone and 17 beta-oestradiol in the aquatic environment

Adsorption of hydrophobic contaminants at the particle/water interface is one of the key processes controlling their fate in the aquatic environment. The sorption of the natural female hormones oestrone and 17g src="/content/n014l154g23354x2/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-oestradiol has been studied under simulated riverine conditions. Both the kinetics and the effects of varying fundamental environmental parameters (e.g. sediment properties) on the thermodynamic equilibrium partition coefficient (gt;Kgt; gt;pgt;) have been studied in continuous and batch sorption experiments, respectively. Results showed that the sorption of oestrone and 17g src="/content/n014l154g23354x2/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-oestradiol by sediment was relatively slow, reaching equilibrium in 50 days. In addition, relatively small adsorption of both oestrone and 17g src="/content/n014l154g23354x2/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-oestradiol onto the sediment was observed, with gt;Kgt; gt;pgt; values between 200 and 250 mL ggt;–1gt;. The comparable gt;Kgt; gt;pgt; values of the two compounds reflect their structural similarity. It can be concluded that the two endocrine disruptors, oestrone and 17g src="/content/n014l154g23354x2/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-oestradiol remain primarily in association with the aqueous phase.     

退耕还林（草）工程实施前后黄土高原植被覆盖时空变化分析

基于GIMMS NDVI3g（the third generation of Global Inventory Modeling and Mapping Studies Normalized Difference Vegetation Index）数据,辅以趋势分析、Mann-Kendall检验、Hurst指数等方法,识别了1982—2013年及1982—1999、2000—2013年黄土高原植被覆盖时空演变特征,并探讨其驱动因素。研究发现：1）1982—2013年及1982—1999、2000—2013年期间黄土高原生长季NDVI分别以0.019/10 a（P<0.01）、0.016/10 a（P<0.05）和0.057/10 a（P<0.001）的速率增加;2）除1999年以前林地外,所有植被类型的生长季NDVI均呈现显著的增加趋势,2000—2013年尤为明显;3）黄土高原生长季NDVI呈现由东南向西北递减的趋势,1982—2013年及1982—1999、2000—2013年NDVI显著上升的面积分别占74.94%、24.26%和53.34%,主要集中在黄土高原的北部和中部地区;4）研究区未来生长季NDVI呈持续性和反持续的比重分别为33.32%和66.68%,其中持续改善和由改善变为退化的面积分别占31.08%和61.88%;5）2000年以后降水增多与生长季NDVI上升相对应,大规模的生态工程建设对2000—2013年生长季NDVI增加有重要影响。     

Dynamics of Turbulence in Low-Speed Oscillating Bottom-Boundary Layers of Stratified Basins

This paper focuses on the impact of an oscillating low-speed current on the structure and dynamics of the bottom-boundary layer (BBL) in a small stratified basin. A set of high-resolution current profile measurements in combination with temperature-microstructure measurements were collected during a complete cycle of the internal oscillation (`seiching') in the BBL of Lake Alpnach, Switzerland. It was found that even a relatively long seiching period of 24 hours significantly changed the form of the near-bottom current profiles as well as the dynamics of the turbulent dissipation rate compared to the steady-state law-of-the-wall. A logarithmic fit to the measured current profiles starting at a distance of 0.5 m above the sediment led to inconsistent estimates of both friction velocity and roughness length. Moreover, a phase lag between the current and the turbulent dissipation of 1.5 hours and a persistent maximum in the current profile at a height of 2.5 to 3 m above the sediment were observed. The experimental findings were compared to the results of a gt;kgt;-gt;g src="/content/w03x0g82559w35q6/xxlarge949.gif" alt="epsi" align="BASELINE" BORDER="0"&gt;gt; turbulence model and showed good agreement in general. Specifically, the inconsistent logarithmic fitting results and the observed phase lag were reproduced well by the model.     

含机油废水微生物降解实验研究

从油污壤中筛选分离出两株高效机油降解菌ZL1、ZL2，初步鉴定为黄杆菌属和微球菌属。通过生长条件正交实验测定了温度、低温浓度和pH值对其降解能力的影响。在废水较高油浓度下进行了连续降解实验。实验表明：20d对于含油270mg／L的去除率分别达到67\9%呼76．2％，其中ZL2菌对底物浓度的pH值有较广的适应范围。     

Comparison of the Vegetation and Seed Bank on Hedge Banks of Different Ages in Brittany,France

The composition of the herbaceous cover and the seed bank of old and recent hedge banks in Brittany were studied and compared. Concentration method was used for seed bank samples. Grimeg src="/content/qp795r7ju9dme7g2/xxlarge8217.gif" alt="rsquo" align="BASELINE" BORDER="0"&gt;s plant strategies were used to explain observed patterns. The analysis of the seed bank of these hedge banks showed that the species richness and diversity differed in relation to the date of construction of the hedge banks. The seed banks of recent hedge banks were richer and more diversified than those of old hedge banks. Differences in the floristic composition of the established plant cover between the recent and old hedge banks were determined by multivariate analyses. The species exclusively found in the seed bank and in the herb cover of recent hedge banks were mainly grassland species, whereas the species that only occurred on old hedge banks tended to be woodland species. The floristic composition of the two compartments (established vegetation and seed bank) was very different. A multivariate analysis revealed that the difference between the composition of the seed banks of recent and old hedge banks was less than that between the composition of the established vegetation and seed bank of hedge banks of the same age. Both seed bank and vegetation of recent hedge banks were dominated by ruderal species, whereas old hedge vegetation was dominated by stress-tolerant woodland species, indicating that mechanically constructed hedge banks may impose limitations on colonization by late woodland species.     

Estimation of Emissions of γ-Hexachlorcyclohexane from the Great Lakes–St. Lawrence Ecosystem Using a Coupled Efficient Kalman Filter–Atmospheric Transport–Soil Model

An efficient linear Kalman filter has been combined with a coupled atmospheric transport and soil–air exchange model to determine organochlorine pesticides emissions on the regional scale. In this study, results of g src="/content/j6g356u510278763/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"&gt;-HCH emissions from the Great Lakes–St. Lawrence ecosystem, estimated from the coupled model, are presented and discussed. A source receptor technique is used to identify a priori the locations of emission sources of g src="/content/j6g356u510278763/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"&gt;-HCH, the emissions are then updated through a Kalman filtering procedure which minimizes the weighted difference between the predicted mixing ratios from the coupled model and the measured concentrations over the Great Lakes–St. Lawrence river region. Two experiments using the inverse algorithm are carried out. In the first experiment, the coupled atmospheric transport and soil–air exchange model is implemented to predict g src="/content/j6g356u510278763/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"&gt;-HCH air and soil concentrations. Emissions are then updated every 12 days using the updated soil concentrations and emission factors. However, the updated emissions are not input into the coupled atmospheric transport and soil–air exchange model. On the other hand, in the second experiment the updated emissions are fed back to the coupled model, so that the model is reinitialized in each 12 days. The results from the inverse technique for the year 1995 have been compared with grided g src="/content/j6g356u510278763/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"&gt;-HCH emission inventory in Canada, generated by emission factors. It is shown that the estimated emissions of g src="/content/j6g356u510278763/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"&gt;-HCH are consistent with the measured emissions. It is found that the St. Lawrence valley has larger emissions of g src="/content/j6g356u510278763/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"&gt;-HCH than the Great Lakes region, indicating an opposite distribution to the emission usage inventory, but in agreement with the measured g src="/content/j6g356u510278763/xxlarge947.gif" alt="gamma" align="MIDDLE" BORDER="0"&gt;-HCH concentration.