脂肪酶产生菌的筛选及其耐甲醇驯化的研究

从土样中分离出34株脂肪酶产生菌,在维多利亚蓝培养基上初筛出透明圈与菌落直径比值较大的6株菌,复筛出产脂肪酶活性较高的菌株FM-1,其所产脂肪酶主要为胞内酶,产脂肪酶活力为132 U/g cell。通过反复的驯化培养方式将菌株FM-1驯化成耐甲醇的优良菌株。在甲醇质量浓度为11 mg/L的培养基中驯化后的脂肪酶相对活力为35%,而出发菌株在此环境中不能生长。     

高盐度废水生物处理现状与前景展望

简要介绍了国内外高含盐量废水生物处理的研究进展，主要有两段接触氧化、传统活性污泥法、SBR、膜法SBR、UASB、厌氧滤池、A^2/O工艺等，以及各种工艺的运行条件和处理状况。各种工艺在高含盐量条件下，经过适当的驯化培养，其他条件适宜，取得较好的处理效果。并介绍利用在高盐环境下生存的嗜盐细菌技术处理高含盐量废水的发展前景。     

SBR反应器中反硝化除磷菌的快速富集

反硝化除磷菌(DPAOs)能够在缺氧条件下同步完成脱氮除磷,是反硝化除磷工艺的主体。以武汉沙湖污水处理厂二沉池的回流污泥为种泥,采用二段式SBR工艺实现了反硝化除磷菌的快速富集。在第一阶段反应器采用厌氧/好氧(A/O)模式运行,可以实现对除磷菌(PAOs)的快速诱导和富集,运行13 d后,SBR反应器对氮、磷的去除率均达到85%以上。而后进入第二阶段,采用厌氧/好氧/缺氧(A/O/A)模式运行,以快速富集培养反硝化除磷菌,经过26 d的运行,反应器对氨氮和磷酸盐的去除率分别达到92.2%和91.2%左右,且典型周期内硝酸盐的消耗量与磷的吸收量基本呈线性关系,表明系统的反硝化除磷能力得到显著增强。     

Anaerobic toxicity and biodegradability of pulp mill waste constituents

Batch bioassays have been conducted to characterize the response of methanogenic bacteria to several constituents of sulfite evaporator condensate. The results can be grouped into three ranges with increasingly severe consequences to anaerobic reactors: a low concentration, no effect range; a medium concentration range where methanogenesis is temporarily interrupted or slowed down, but may return to normal; and a high concentration range where methanogenesis is permanently inhibited. In some cases the toxicant was metabolized when present in the lower concentration ranges. There was also evidence that mechanisms other than fermentation to methane were significant in accounting for removal of the toxicants from solution. Organisms acclimated to low concentrations of a toxicant are better able to withstand a shock load of that toxicant than are unacclimated organisms.     

激光预处理种子提高大豆幼苗抗冷害的机理探讨

从能量转移、膜系统和自由基3个方面探讨了激光预处理大豆种子提高其幼苗抗寒性的机理.研究结果表明,激光(He-Ne)预处理大豆种子不但明显地提高大豆种子三磷酸腺苷(ATP)的含量,而且提高其幼苗(子叶期到第一真叶期)的抗低温胁迫的能力.处理组幼苗在3℃～5℃低温胁迫下比对照组有较高的过氧化氢酶(CAT)、过氧化物酶(POD)、超氧化物歧化酶(SOD)和淀粉酶(AML)的活性及可溶性蛋白质含量.同时预处理还降低了幼苗子叶中超氧阴离子(O2-)含量、丙二醛(MDA)的积累量及电解质外渗率.     

The effects of selected chemicals and water quality on the marine polychaete : Ophryotrocha Diadema

Cultures of a dorvilleid polychaete, Ophryotrocha diadema. have been used here to test the toxicity of a range of pure chemicals, including metals and pesticides. The 48-h LC₅₀ values are reported. In comparison with other marine polychaetes currently used in toxicity tests, O. diadema was found to be equally sensitive to most of the potential pollutants. In an attempt to increase the tolerance of O. diadema to metals. 12 generations were grown during an 18 month period in sea water containing sublethal concentrations of mercury, copper and zinc. This treatment caused an increase in the generation time of the cultures. Acute toxicity tests on the parent. F₅ and F₁₂ generations were not significantly different from each other and it was concluded that there was no measurable increase in tolerance. O. diadema was tested for the bioassay of polluted water by culturing it in water from Belfast Lough, a semi-enclosed marine bay which is used for the disposal of domestic and trade waste. The growth of the parents from 6-segment to adult stage was normal, but egg production was both delayed and reduced in water from the lough when compared to water from a clean source. However, this effect could not be attributed conclusively to anthropogenic contamination.     

复合生物反应器挂膜及污泥驯化试验

将已培养的适于焦化废水处理的优势菌种用好氧污泥固定化后投入挂有纤维球串体的复合生物反应器中,采用逐步提高焦化废水配比的方法进行生物挂膜及污泥驯化试验研究。试验结果表明:挂膜很成功且驯化效果良好。挂膜结束时,纤维球串体周围生长了一层厚厚的附着层污泥,底部悬浮相污泥絮体大且蓬松,出水澄清透明;驯化结束时,当焦化废水的进水COD和NH3-N的质量浓度分别小于850mg/L和280mg/L时,二者的去除率分别可达95%和87%以上,焦化废水的色度有所降低。     

甜玉米冰温贮藏保鲜研究

研究不同冰温处理对甜玉米贮藏保鲜效果的影响.设计三组实验:直接冰温、装袋+冰温、装袋后低温锻炼+冰温.以含水量、水渍发生率、失重率和总糖为理化指标,并结合感官方法进行综合分析.结果表明:经过5d 4～C低温锻炼后再进行冰温贮藏,19d后甜玉米色香味和口感俱佳,水溃发生率为20%、玉米穗失重率为2.84%、玉米粒含糖量下降12.41%、含水率下降0.34%,分别比对照组降低30%、11.84%、2.15%和1.66%.     

准好氧生物反应器处理渗滤液系统的驯化研究

将准好氧填埋技术与矿化垃圾技术相结合在实验室内构建了模拟准好氧生物反应器垃圾处理系统,以室内埋龄为3年的矿化垃圾填充准好氧生物反应器,以室内模拟垃圾填埋柱产生的新鲜渗滤液为处理对象,考察了混合培养法、容积负荷渐增法和水力负荷渐增法对反应器内微生物的驯化效果.结果表明,混合培养法较负荷渐增法的驯化效果好,在驯化结束时,采用混合培养法的反应器出水COD为305 mg/L,NH3-N为0.6 mg/L,TN为38.7 mg/L;驯化时间越长则驯化效果越好,同是容积负荷渐增法,经过30 d分阶段驯化和经过20 d分阶段驯化的反应器,其出水COD分别为381 mg/L和1 311 mg/L,NH3-N分别为0.8 mg/L和5.0 mg/L.在准好氧生物反应器处理渗滤液系统的工程应用中,对微生物的驯化可首选混合培养法,同时应保证一定的驯化时间.