Bumblebees of the Azores (Apidae: Bombus)

Bombus terrestris and Bombus pratorum were found for the first time in the Azores in 2005. Until then Bombus ruderatus was the only bumblebee species known from this group of nine mid-Atlantic islands. The identity of B. terrestris was confirmed by DNA barcoding.     

自然水体生物膜有机质含量测定方法的建立与评价

用TOC作为自然水体生物膜中有机质含量的代表性指标,利用SSM-5000A型固体燃烧装置测定南湖培养的生物膜的TOC,通过对结果准确度,精密度的探讨,发现用此种方法测定生物膜上的有机质含量的稳定性较好、准确度较高,且操作过程简单,测定时间短。     

表皮葡萄球菌sigB基因调控生物膜合成的研究

sigB基因编码的S igm a factor B(σB)蛋白是一个普遍性的可通过与RNA聚合酶结合来调控多种基因表达的因子.为了验证表皮葡萄球菌sigB基因的调控作用,构建了含四环素抗性基因的打靶载体并采用双交换同源重组的方法对表皮葡萄球菌RP62A(ATCC35984)中sigB基因进行敲除.sigB基因敲除后的菌株,与出发菌株相比生物膜形成能力急剧下降,而在sigB基因座的回补菌株中,生物膜形成能力又恢复到接近出发菌株的水平.RT-PCR分析生物膜相关基因sarA(Staphylococcus Accessory Regu lator),icaA(icaADBC操纵子中的第一个基因)发现,sigB基因从转录水平上对二者进行正调控.lacZ报告系统的体外实验揭示了SigB可以通过作用于sarA的启动子区域正调控sarA表达.     

生物接触氧化法处理富马酸废水

采用好氧生物膜接触氧化法处理富马酸废水,用盾式纤维填料作为生物的支持物,研究生物降解富马酸的原理和不同工艺条件对富马酸废水降解的影响．实验结果表明,富马酸的降解符合一级反应规律,最佳的反应气水比为16,控制水力停留时间为8h．当富马酸废水COD和BOD,分别增至l800mg／L和520mg／L时,处理后的废水的COD约为216mg／L,BOD,约为114mg／L,BOD,与COD的比值为0.53．在反应器容积负荷提高到原来的7．6倍,运行40h后,COD去除率约可恢复到70％,表明生物膜接触氧化反应器具有较大的缓冲能力,其抗冲击负荷能力较强。     

苦参与环丙沙星合用对铜绿假单胞菌生物膜的影响

采用体外复制铜绿假单胞菌生物膜模型,研究了苦参水煎液与环丙沙星联合应用对铜绿假单胞菌生物膜的影响及协同杀菌效果,结果显示,1/16、1/4最小抑菌浓度(Minimal Inhibitory Concentration MIC)的苦参水煎液可显著增加1/41、/2 MIC的环丙沙星对铜绿假单胞菌生物膜的抑菌活性,两药合用具有明显的协同作用.     

内循环三相流化床的生物膜的培养

研究了内循环三相流化床在两种不同进水方式情况下生物膜培养情况. 研究表明:间歇进水时生成的生物膜能达到200～250?m左右,连续进水时生物膜厚度能达到100?m;前者较为圆滑紧密,而后者的活性较高;较低的启动容积负荷有利于启动挂膜;挂膜完成后进水的容积负荷不能过低,否则容易因污泥负荷低而引起丝状菌膨胀. 通过间歇式进水培养的活性污泥达到了生物量9.65g·L-1(其中附着生物膜占92.7%),而连续式进水负荷COD可以达到11.45kg·m-3·d-1, 此时COD去除率达到80%.     

Diversity of arbuscular mycorrhizal fungi associated with desert ephemerals growing under and beyond the canopies of Tamarisk shrubs

The arbuscular mycorrhizal （AM） fungal status of the four most common ephemeral plant species, Chorispora tenella （Pall.） DC., Ceratocephalus testiculatus （Crantz） Bess., Eremopyrum orientale （L.） Jaub et. Spash and Veronica campyIopoda Boiss growing in an area dominated by Tamarisk shrubs （Tamarix spp.） was investigated. Samples of the four ephemerals and their rhizosphere soils were collected from underneath and beyond the canopies of the Tamarisk shrubs. Plant mycorrhizal status and soil AM fungal spore densities and community structures were analyzed and compared under and beyond the shrub canopies. The mycorrhizal colonization rates of the ephemerals and spore densities in their corresponding rhizosphere soils were significantly lower under the shrub canopies than beyond. The number of AM fungal species under the shrubs （12） was also lower than beyond the canopies （19）. When soil properties in the rhizospheres of the four ephemerals were examined, available N and P and total P, organic matter content, total salt content and electrical conductivity （EC） were all higher under the canopies than beyond. In contrast, soil available K and pH showed no such trend. A total of 21 AM fungal species were isolated from rhizosphere soils of the four ephemerals. Five belonged to Acaulospora, one to Archaeospora, thirteen to Glomus and two to Paraglomus. We conclude that the canopies of Tamarix spp. exerted some influence on the AM status of the ephemerals and on the AM fungal communities and some of the properties of their rhizosphere soils.     

降解氯苯废气生物滴滤塔挂膜启动方式

以装填活性炭纤维布填料的生物滴滤塔为试验装置,以模拟氯苯废气为降解目标物,分别采用快速排泥法和气液相联合法对滴滤塔进行挂膜启动。结果表明:气液相联合法23 d实现挂膜启动,比快速排泥法挂膜启动时间缩短20 d左右,去除率变化更加稳定,进气中氯苯浓度4 000 mg/m3时两者去除率均达到50%。     

SBR法处理啤酒废水有机质降解动力学研究

利用活性污泥SBR法和生物膜SBR法进行有机质降解过程和降解动力学参数的比较研究。每个SBR反应器总容积为4 L,有效容积为3 L。生物膜SBR法的填料采用海产品废弃物贝壳,填充的堆积体积为1.5 L,填充率为10%;贝壳大小为2 cm×3 cm。进水水质指标为COD 396～457 mg.L-1,NH4-N46 mg.L-1,TP9.4 mg.L-1,pH6.50,水温14℃。运行周期为12 h,其中曝气10 h,沉淀1 h,排水和进水1 h。每次排水1.5 L,进水1.5 L。在试验稳定运行两周后开始研究有机质降解动力学过程,活性污泥SBR法和生物膜SBR法的MLSS分别为4 321,7 729 mg.L-1,获得的Vmax分别为0.024,0.031 d-1;Ks分别为121.9,57.71 mg.L-1;K2分别为0.000 20,0.000 54 L.mg-1.h-1。生物膜SBR法有机质降解过程没有表现出初期吸附特征,而是COD浓度持续下降的过程。