一株长江优势菌的降解特性研究

从长江水体中分离到一株最优功能菌株JD1,经初步鉴定该菌株为琼氏不动杆菌属(acinetobacter junii)。该菌株最高可耐受质量浓度600 mg/L的乐果,降解乐果的最适温度为32℃,在30~37℃的广泛温度下仍生长良好,最适pH值为7.2左右,具有广泛的pH值生长范围(pH=5.5~9.0)。研究发现,装液量、接种量对菌株的降解有明显影响。装液量由3/10调整为1/5时,JD1对质量浓度100 mg/L的乐果降解率从21%提高到51.54%。试验表明,该菌株可以在质量浓度高达2 400 mg/L的苯酚中生长良好。     

低温苯胺降解菌的筛选及其特性

通过驯化培养,从含苯胺的管道污泥中分离出1株高效苯胺降解菌7#,在苯胺质量浓度低于5500 mg/L的普通培养基中均可生长。7#菌株降解苯胺的最适温度为30℃,经低温驯化后,10℃和30℃时对苯胺的降解率接近,最适pH=7.0,当苯胺质量浓度在400 mg/L以下时,对该菌不表现出明显抑制作用。在苯胺质量浓度200 mg/L的无机盐溶液中,10℃下培养60 h可使苯胺降解率达89.14%,降解符合二级动力学模型。经鉴定,该菌株为假单胞菌属。     

MBR处理聚乙烯醇废水的试验研究

理论分析和试验结果表明 :采用一体式好氧膜生物反应器 (MBR)处理难降解聚乙烯醇有机废水 ,在 pH为 7～ 8,温度为 15～ 2 9℃ ,HRT为 10～ 2 0h ,SRT为 10 0d ,进水COD为 10 0～ 6 0 0mg/L的条件下 ,系统出水COD在 4 0mg/L以下 ,平均为 15 5mg/L ,COD的平均去除率为 90 7%。采用好氧MBR能有效地处理难降解聚乙烯醇有机废水     

高效降解PCBs的优势菌种选育研究

以PCBs为目标污染物,筛选出具有高效降解能力的优势菌株P1和P2,通过16SrDNA序列的测定和同源性比较分析,分别将其鉴定为产碱菌属(Alcaligenes sp.)和芽孢杆菌属(Bacillus sp.),并通过驯化提高其降解能力。通过实验研究生长条件对PCBs去除效果的影响。实验得出最佳降解条件:温度为30℃,pH值为7,菌体接种量为5 mL。7 d的降解率最高可达98.2%。     

一株硫酸盐还原菌的分离及处理含铁锰废水的实验

通过实验分离并纯化出一株硫酸盐还原菌(编号为SRBd),初步鉴定为脱硫杆菌属(Desulfobacter);对SRBd菌株在不同菌液投加量、pH值、振荡强度及其碳硫条件下进行Fe2+、Mn2+去除特性实验,得出反应的最佳条件为:温度为37℃、pH值为6、震荡强度为100 r/min、COD/SO42-为2/1,在此最佳条件下对SO42-、Fe2+、Mn2+的去除率分别为88.16%、99.37%、59.18%,SRBd具有较好的铁锰去除能力,该研究成果可为生物法处理AMD提供一定的参考依据。     

表面活性剂LAS高效降解菌的筛选及降解性能的研究

从洗涤剂污泥中分离到一株对LAS活性很高的降解菌Wg~(-1)。该菌初步鉴定为假单胞菌(Pseudomonas sp.)。其最适生长pH为 7,温度为30℃,LAS浓度为 800mg/L。当LAS初始浓度高于800mg/L时,Wg~(-1)对LAS的降解率随底物浓度的增加而降低。该菌对LAS具有很强的耐受性,在LAS浓度达4000 mg/L时,仍能较好地生长并发挥降解作用。Wg~(-1)的生长速度及降解能力均是空白对照(CK)的几倍甚至几十倍。     

研究生论文摘要

酵母菌处理啤酒发酵废水同时生产单细胞蛋白的研究研究生:刘红霞导师:马放副导师:于秀娟(哈尔滨工业大学市政环境工程学院150090)利用啤酒废水生产单细胞蛋白可以高效地降解啤酒发酵工业废水,减少环境污染,同时可获得单细胞蛋白(SCP)。研究了啤酒厂发酵车间废水中微生物菌群的特性,分离出主要优势菌群,包括3株细菌和3株酵母菌,通过鉴定分别属于芽孢杆菌属、短杆菌属、动胶菌属、酵母属、假丝酵母属和毕赤酵母属。研究了3株酵母菌降解废水和单细胞蛋白生成能力,确定上述3株酵母菌不适于单细胞蛋白的生产。研究了3种市售酵母菌处理啤酒废水…     

白腐菌-厌氧菌-好氧菌三段式处理蒸煮黑液工艺研究

造纸蒸煮黑液是高浓度、高碱性的有机废水。由于高碱性和木质素等难降解物质的存在 ,给蒸煮黑液的处理带来了很大的难度。采用产酸白腐菌株S调节黑液pH ,去除与转化木质素 ,结果 pH由 8降至 3以下 ,COD由 10 0 0 0mg/L左右降至 5 0 0 0mg/L ,显著改善了黑液的可生化性。出水经白腐菌株C调节 pH后 ,利用厌氧菌水解和好氧菌接触氧化工艺进一步处理。研究了各工序进水负荷、停留时间、温度等因素对处理效果的影响 ,获得了有效处理蒸煮黑液的工艺参数 :进水黑液负荷 10 0 0 0mg/L左右 ,停留时间分别为 3d ,4h和 2 4h ,温度在 2 5～ 2 9℃下 ,连续运行 2 0余天 ,COD总去除率达 91 5 %～ 96 5 %。在整个工艺中 ,发现白腐菌的作用占主导地位 ,而黑液负荷、温度、pH是影响白腐菌作用的重要因素。     

苯酚降解菌筛选及降解特性研究

针对焦化废水生物难降解有机物含量高、实际生产过程中的水质和水量变化大的特点,开展了高效菌株处理含酚废水的试验研究。从某焦化厂水处理车间生物处理装置曝气池活性污泥中驯化、分离和筛选得到4株以苯酚为唯一碳源的高效降解菌,并对其进行鉴定及降解特性研究。结果表明:初步鉴定h32a2、b31B、h31A和b41a为假单胞菌属(Pseudomonas sp.);通过溴化容量法测定苯酚含量,确定了菌株的最佳降解条件为:温度32℃,p H值7.5,培养时间16 h,接种密度1%,且单一菌株h32a2的苯酚最大降解率可达90.55%。通过单一和组合高效菌株对苯酚的降解特性可知,4株高效菌混合的降解效果最佳。因此,混合高效苯酚降解菌处理含酚废水具有一定的可行性。     

水解酸化-气浮-SBR工艺处理亚麻废水

亚麻废水是一种较难降解的有机废水 ,用单一的好氧生物法处理效果不好。采用水解酸化 气浮 SBR工艺处理亚麻废水 ,设计处理能力 10 0 0m3/d ,设计废水水质为 :COD 80 0～ 10 0 0mg/L ,BOD 4 0 0～ 5 0 0mg/L ,SS 2 0 0～ 30 0mg/L ,pH 7。在保证酸化水解调节池正常运行的条件下 ,COD去除率可达 2 5 %以上 ,再经气浮及SBR处理 ,COD去除率可达 85 % ,出水水质达标     

Call for Papers

正As the eldest and most distributed professional journal of water industry,Water Wastewater Engineering(W WE)gained very wide acceptance from the colleagues working in this field in this country since start publication in 1964.Now it is administrated by the Ministry of Construction of the People’s Republic of China and sponsored by the China Civil Engineering Society etc.     

地下厂房施工过程的三维非线性数值模拟分析

根据冗各电站地下厂房开挖支护的施工顺序,以隐式杆单元模拟锚杆,以壳单元模拟混凝土喷层,采用三维非线性有限元技术,对洞室群的开挖支护动态过程进行了模拟计算。通过三维非线性有限元计算分析得到:洞室群动态开挖过程中围岩应力变形的分布规律,围岩塑性区的发展规律,锚杆受力变化情况。计算结果表明:整个开挖过程中,洞周围岩位移变化规律正常,量值较小,塑性区主要分布在洞室周边,围岩稳定性较好;但在洞室交叉口处围岩的变形较大,出现较大范围的塑性区,在此基础上提出了支护措施优化方案,并对优化方案的效果进行了评价。     

Evaluation of freshwater mussel relocation as a conservation and management strategy

The relocation of unionacean mussels is commonly used as a conservation and management tool in large rivers and streams. Relocation has been used to recolonize areas where mussel populations have been eliminated by prior pollution events, to remove mussels from construction zones and to re-establish populations of endangered species. More recently, relocation has been used to protect native freshwater mussels from colonization by the exotic zebra mussel Dreissena polymorpha. We conducted a literature review of mussel relocations and evaluated their relative success as a conservation and management strategy. We found that 43% of all relocations were conducted because of construction projects that were forced to comply with the Endangered Species Act 1973 and that only 16% were monitored for five or more consecutive years. Most (43%) relocation projects were conducted from July to September, presumably a period when reproductive stress is relatively low for most species and the metabolic rate is sufficient for reburrowing in the substrate. The mortality of relocated mussels was unreported in 27% of projects; reported mortality varied widely among projects and species and was difficult to assess. The mean mortality of relocated mussels was 49% based on an average recovery rate of 43%. There is little guidance on the methods for relocation or for monitoring the subsequent long-term status of relocated mussels. Based on this evaluation, research is needed to develop criteria for selecting a suitable relocation site and to establish appropriate methods and guidelines for conducting relocation projects.     

基于模型试验的河床砂砾石层基本特性研究

为了经济可靠地确定深厚覆盖层的基本特性参数,以大渡河双江口水电站坝基河床砂砾石层基本特性研究为工程背景,进行大尺寸模型试验,研究河床砂砾石层的旁压模量和动探击数随密度、级配以及上覆压力的变化规律。根据室内模型试验结果,结合现场旁压试验及钻孔试验成果,推断出坝址区河床砂砾石相关层位的密度,并依此进行砂砾石室内力学试验,获得设计所需力学参数。研究成果可为深厚覆盖层基本特性测试提供新的方法。     

库水波动下库岸边坡地下水浸润线解析解及误差分析

解析法是库岸边坡地下水浸润线计算中便于实际应用的方法,但该方法须基于若干假定并对潜水运动基本方程线性化后才能求解。针对各假定和线性化过程建立不同的地下水渗流数学模型,用解析法和有限元法解答上述数学模型,分析各误差大小及其规律。结果表明：库岸垂直处理带来的误差要小于方程线性化处理和不考虑非饱和渗流带来的误差,而且它们都随渗透系数变大而减小;在三峡库区库水调度情况下,假定库水位等速变化带来的误差对大多岸坡而言可以忽略;计算库岸边坡地下水浸润线时,解析法只适用于水位变化幅度相比含水层厚度较小,且几何边界规则、岩土结构简单、岩土体渗透性较好时的情况。     

SPATIAL AND TEMPORAL WATER QUALITY VARIABILITY IN AQUATIC HABITATS OF A CULTIVATED FLOODPLAIN

The floodplains of lowland rivers contain diverse aquatic habitats that provide valuable ecosystem services but are perturbed when intensively cultivated. Hydrologic, water chemistry and biological (fish) conditions in five aquatic habitats along the Coldwater River, Mississippi, were measured for more than 4 years: the river, two severed meanders that functioned as backwaters, a managed wetland and an ephemeral channel draining cultivated fields. Off‐channel habitats were connected to downstream regions 0.10% to 32% of the dry season and 24% to 67% of the wet season. The median temperatures for the five monitored sites ranged from 18°C to 23°C, the median total solids concentration for all sites was 135 mg L^?1, the median total phosphorus was 0.29 mg L^?1 and the median total nitrogen was 1.56 mg L^?1. Chemical and physical water quality displayed strong seasonal differences between the wet winter/spring and the dry summer/fall periods so that temporal variation consisted of gradual seasonal trends superimposed on strong diurnal variations. All off‐channel habitats exhibited periods of hypoxia and temperatures >30°C during the dry season. Between‐site gradients of water and habitat quality were strongly coupled to water depth and runoff loading. The rehabilitation of one backwater by increasing water depth and diverting agricultural runoff was associated with improved water quality and fish species richness relative to an adjacent untreated backwater. The diversion of polluted runoff and the use of water control structures to maintain greater water depth were observed to be effective management tools, but the former reduces the water supply to habitats that tend to dry up and the latter reduces connectivity. Published in 2011 by John Wiley & Sons, Ltd.     

Changes in Summer Irrigated Crop Area and Water Use in Southeastern Turkey from 1993 to 2002: Implications for Current and Future Water Resources

Changes in summer irrigated cropland acreage and related water use are estimated from satellite remote sensing and ancillary data in semi-arid Southeastern Turkey where traditionally dry agricultural lands are being rapidly transformed into irrigated fields with the help of water from the Euphrates-Tigris Rivers. An image classification methodology based on thresholding of Landsat NDVI images from the peak summer period reveals that the total area of summer irrigated crops has increased three-fold (from 35,000 ha to over 100,000) in the Harran Plain between 1993 and 2002. Coupled analysis of annual irrigated crop area from remote sensing and potential evapotranspiration based estimates of irrigation water requirements for cotton indicate a corresponding increase in agricultural water use from about 370 million cubic meters to over one billion cubic meters, a volume in accordance with the state estimates. These estimates have important implications for understanding the rapid changes in current agricultural withdrawals in Southeastern Turkey and form a quantitative basis for exploring the changes in future water demands in the region. For example, expansion of irrigated lands have led to a steady decrease in potential evaporation due to increased roughness and decreased humidity deficit in the Harran Plain. Assuming that the changes in future evaporation conditions will be of similar nature, water use for irrigation is expected to decrease over 40 percent in future irrigation sites. Incorporating this decrease in overall planning of the irrigation projects currently under construction should lead to improved management, and by extension, sustainability of water resources in the region.     

基于BP神经网络-马尔科夫链模型的隧道围岩位移预测

在隧道工程施工中,围岩位移预测起着很重要的作用。将BP神经网络-马尔科夫链模型引入到隧道围岩位移预测中来,通过对训练样本的学习,利用BP神经网络实现了对位移时间序列的滚动预测,同时得到了实测值与预测值的相对误差;在此基础上利用马尔科夫链对相对误差进行修正,有效地提高了预测结果的精度。并将该模型应用于某公路隧道拱顶下沉位移时序预测中,结果表明该模型具有精度高、科学可靠的特点,为隧道围岩变形的预测提供了新的途径。     

Short communication. Pipelines as a refuge for freshwater snails

In the lower River Murray, Australia, populations of gastropods have declined markedly over the past 40 years. Of the native fauna of about 18 species, only the ancylid Ferrissia petterdi remains common (but in patches), and another five species feature in sporadic local resurgences. Until recently the viviparid Notopala was thought to be extinct. The introduced physid Physa acuta is widespread, but in low numbers. The decline probably is associated with flow regulation, high turbidity and the introduction of common carp. Snail populations have persisted, however, in irrigation pipelines fed from the river, where they periodically cause blockages. This paper reports the discovery of the only known populaion of Notopala hanleyi in a pipeline where the inner wall accumulates microbial and other organic matter, providing high quality food for snails. In the Murray before regulation most of the periphytic biomass was probably microbial, as fluctuating water levels would have maintained littoral communities in a highly productive, early state of succession his postulated that, by stabilizing seasonal water levels, regulation has promoted the production of filamentous green algae, an inferior food source, and so displaced snail populations from the open aquatic environment.     

Spatio‐temporal variation of gross CO2 and CH4 diffusive emissions from Australian reservoirs and natural aquatic ecosystems,and estimation of net reservoir emissions

Carbon dioxide (CO₂) and methane (CH₄) diffusive emissions were measured during two field surveys in Queensland and Tasmania, Australia, using the floating chamber method. Bubbling and degassing emissions in 2010 were estimated in Koombooloomba Dam reservoir using only inverted funnels and gas concentrations, respectively. A total of 14 reservoirs and 16 rivers and lakes were sampled from 2006 to 2010. Spatial variation was substantial within each water body, as well as between them. The main drivers of diffusive emission variation were physiographic region and climate, with a clear demarcation being observed between diffusive emissions from tropical Queensland and temperate Tasmania, and between the humid West Coast Range (Tasmania) and dry Central Plateau (Tasmania). Higher CO₂ and CH₄ diffusive emissions were observed during the dry season, when long water residence times would promote organic matter degradation. Estimated total gross emissions, including diffusive, bubbling and degassing emissions, for Koombooloomba Dam reservoir were about 1.5 × 10⁶ t CO₂eq km² per year, or 24 × 10⁶ t CO₂eq per year. This corresponds to a plant emission factor of 3.18 kg CO₂eq MWh^?1. Using an estimate of terrestrial emissions derived from literature data for the Tully River catchment area, rough estimated net emissions from the catchment area are about 44 kt CO₂eq per year, or 5.83 kg CO₂eq MWh^?1, which is in the lower range of the studied reservoirs.