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81.
厌氧氨氧化是细菌在厌氧条件下将氨氮氧化成氮气的过程,主要应用在污水处理反应器中,最近几年发现在海洋环境中也广泛存在,并在海洋氮循环过程中发挥了重要作用,代表了海洋中一个巨大的氮汇,对碳循环和全球气候变化也有重要影响。梯烷膜脂结构独特,是厌氧氨氧化细菌的化学生物标志物,具有化学分类与古海洋学应用潜力。厌氧氨氧化作用及厌氧氨氧化细菌已成为海洋生物地球化学、微生物学、有机地球化学等研究领域的热点。  相似文献   
82.
新疆准噶尔盆地独山子泥火山天然气地球化学特征   总被引:2,自引:0,他引:2  
独山子泥火山位于新疆准噶尔盆地南缘, 地处北天山山前坳陷带的独山子背斜轴部。本文通过分析独山子泥火山喷出天然气组分及其碳同位素研究, 对天然气的来源进行了判识。3个天然气样中δ13C1值均在–41‰左右, C1/(C2+C3)<20, 为热成因气; δ13C(C2-C1)在15‰左右, iC4/nC4和C2/C3值均较高, 说明天然气曾遭受了厌氧微生物降解作用; 其中两个喷口的天然气δ13CCO2值超过+10‰, 说明天然气在受微生物降解后发生CO2还原作用二次生成甲烷, 而另外一个喷口δ13CCO2值无正异常, 未发生CO2还原作用。不同喷口相同成因天然气在储藏或运移过程中发生不同的改造作用, 说明泥火山不同喷口对应不同的天然气运移通道或储藏条件。  相似文献   
83.
The well-preserved Mesoproterozoic succession in the North China platform consists mainly of three llthological associations including peritidal quartz sandstone, shallow marine and lagoonai dark to black shales, and shallow epeiric carbonates, with a total thickness of up to 8 000 m. In addition to well-documented microplants, macroalgae, and microbial buildups, abundant microbially induced sedimentary structures (MISS) and mat-related sediments have been recognized in these rocks. Intensive microbial mat layers and MISS are especially well preserved in the carbonates of the upper Gaoyuzhuang (高于庄) (ca. 1.5 Ga) and lower Wumishan (雾迷山) (ca. 1.45 Ga) formations, Indicating diversified microbial activities and a high organic production. In these petrified blomats, putative microbial fossils (both coccoidal and filamentous) and framboidal pyrites have been identified. The abundance of authigenic carbonate minerals in the host rocks, such as, acicular aragnnites, rosette barites, radial siderites, ankerites, and botryoidai carbonate cements, suggests authigenlc carbonate precipitation from anaerobic oxidation of methane (AOM) under anoxic/euxinic conditions. Warm climate and anoxic/euxinic conditions in the Mesoproterozoic oceans may have facilitated high microbial productivity and organic burial in sediments. Although authigenic carbonate cements may record carbonate precipitation from anaerobic methane oxidation, gas blister (or dome) structures may indicate gas release from active methanogenesls during shallow burial Bituminous fragments in mat-related carbonates also provide evidence for hydrocarbon generation. Under proper conditions, the Mesoproterozoic mat-rich carbonates will have the potential for hydrocarbon generation and serve as source rocks. On the basis of petrified biomats, a rough estimation suggests that the Mesoproterozoic carbonates of the North China platform might have a hydrocarbon production potential in theorder of 10×108t.  相似文献   
84.
矿物材料对废水厌氧处理及厌氧污泥改性具有十分重要的作用,而微生物代谢产物是生物处理系统的重要组分,在提高污染物去除率和甲烷产量等方面也起到非常重要的作用。本研究对矿物材料石墨和厌氧微生物共存体系内溶解性微生物产物(soluble microbial product,SMP)和胞外聚合物(extracellular polymeric substances,EPS)进行了分析表征。结果表明,石墨对EPS和SMP的组成和含量影响显著,主要是由于石墨的吸附作用及其对石墨颗粒的环境毒性所致。红外光谱分析表明,添加石墨体系内SMP与EPS的基团种类并未发生明显改变,但含量有所改变。三维荧光分析结果显示,SMP的主要荧光类物质为色氨酸类似物和腐殖质(辅酶NADH),而EPS的主要荧光类物质为色氨酸类似物和腐殖酸,石墨能明显降低色氨酸类似物及腐殖酸类物质的产生。石墨会减弱微生物的相对疏水性,提高表面自由能,有利于微生物团聚体的形成。  相似文献   
85.
The study aims to reveal phylogenetic and evolutionary relationship between aerobic anoxygenic phototrophic bacteria (AAnPB) and their relatives, anaerobic anoxygenic phototrophic bacteria (AnAnPB) and nonphototrophic bacteria (NPB, which had high homology of 16S rDNA gene with AAnPB and fell into the same genus), and validate reliability and usefulness of farnesyl pyrophosphate synthase (FPPS) gene for the phylogenetic determination. FPPS genes with our modified primers and 16S rDNA genes with general primers, were amplified and sequenced or retrieved from GenBank database. In contrast to 16S rDNA gene phylogenetic tree, AAnPB were grouped into two clusters and one branch alone with no intermingling with NPB and AnAnPB in the tree constructed on FPPS. One branch of AAnPB, in both trees, was located closer to outgroup species than AnAnPB, which implicated that some AAnPB would be diverged earlier in FPPS evolutionary history than AnAnPB and NPB. Some AAnPB and NPB were closer located in both trees and this suggested that they were the closer relatives than AnAnPB. Combination codon usage in FPPS with phylogenetic analysis, the results indicates that FPPS gene and 16S rRNA gene have similar evolutionary pattern but the former seems to be more reliable and useful in determining the phylogenic and evolutionary relationship between AAnPB and their relatives. This is the first attempt to use a molecular marker beside 16S rRNA gene for studying the phylogeny of AAnPB, and the study may also be helpful in understanding the evolutionary relationship among phototrophic microbes and the trends of photosynthetic genes transfer.  相似文献   
86.
厌氧接触消化技术处理高浓度淀粉废水研究   总被引:1,自引:0,他引:1  
实验采用厌氧接触消化技术,分别在中温(32℃)和自然温度条件下处理淀粉厂的高浓度废水。结果表明,采用中温厌氧消化可取得较好的处理效果,原水不调pH(原水pH为4.0~4.9)直接进反应器,容积负荷最高达5.06kgCODcr/m3·d,进水CODcr平均11.604×103mg/l,出水CODcr平均1.778×103mg/l,CODcr去除率达85.8%,出水pH提高到6.4~7.0。采用自然温度消化,当气温大于24℃时,可取得较好的处理效果  相似文献   
87.
The degradation of acyclic petroleum hydrocarbons was studied during a 24-month experiment in Mediterranean coastal sediments (Gulf of Fos). Sediment cores entirely contaminated with oil (Arabian Light Crude Oil) were incubated in situ. The use of conservative tracers of sediment's particles reworking (luminophores) allowed the distinction of the reworked layer from the anoxic deeper sediments. Using the 17α,21βC30 hopane (C30H) as an inert internal reference, we could demonstrate that, after 24 months of experiment, acyclic petroleum hydrocarbons can be degraded under natural anaerobic conditions. The reactivity of individual alkanes appeared to depend on their chemical structure. To cite this article: D. Massias et al., C. R. Geoscience 335 (2003).To cite this article: D. Massias et al., C. R. Geoscience 335 (2003).  相似文献   
88.
This research was carried out with the aim to explore the heterotrophic microbial population of two sediments in different oxic conditions of the Lake of Lugano (Lago di Lugano). The values of the viable bacterial counts found in our sediment samples were typical for an eutrophic lake.The increase in the proportion of anaerobic to aerobic bacteria at 30 °C observed in the sediment samples of Agno may reflect the depletion of oxygen concentrations in the water column.The generaAeromonas, Pseudomonas, Bacillus andClostridium, as well as strains belonging to the Coryneform-group, represented the major taxonomic groups of heterotrophic bacterial communities in the water-sediment interface.  相似文献   
89.
污泥屏障渗透性及重金属阻截效果试验研究   总被引:1,自引:0,他引:1  
张虎元  杨博  高全全  张光伟 《岩土力学》2012,33(10):2910-2916
目前,废弃物处置场渗滤液中的重金属污染物只能依靠极低渗透性的水力屏障来控制,还不存在利用化学场专门拦截重金属污染物的反应型屏障。在有机结合生活污泥的低渗透性与丰富的有机质和厌氧微生物特性的基础上,提出“污泥屏障”的构想。研究利用柔性壁渗透仪测量不同有效应力作用下生活污泥试样的渗透系数,并对渗出液的化学性质进行了监测,验证污泥屏障的可行性。试验结果表明:随着有效应力的增大,污泥试样干密度提高,渗透系数的对数值随孔隙比的减小线性降低。试样内部微生物厌氧呼吸形成的生物膜和无机物沉淀以及黏土颗粒双电层厚度的增大,也是污泥渗透系数降低的原因,污泥渗透系数仅为 数量级。另外,污泥强烈吸附能力及厌氧微生物呼吸作用形成的中-弱碱性还原环境,对渗透液中的Zn和Cd都起到了很好的拦截作用。  相似文献   
90.
UASB处理猪粪废水启动试验研究   总被引:1,自引:0,他引:1       下载免费PDF全文
通过UASB反应器处理猪粪废水试验,研究了UASB处理猪粪废水的启动过程。在水浴35℃时,接种处理啤酒废水的厌氧颗粒污泥,通过控制较低的表面水力负荷,经逐步驯化66 d,完成了启动过程。结果表明:UASB反应器对COD的去除率为88.5%,其容积负荷达到10.9 kg/(m3.d),SS去除率为90.0%或以上。试验可为农村地区资源化技术提供一定的科学依据和借鉴。  相似文献   
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