金属硫化矿的微生物脱硫可行性分析

矿石的高含硫足导致高硫矿自燃的内因,利用微生物浸矿技术脱除硫化矿表面的硫,把矿石表面禽硫量降至自燃临界值以下,来避免高硫矿矿井内因火灾的发生。本文通过对微生物脱除煤炭中硫及硫铁矿烧淹中硫的对比分析,结果表明,利用微生物脱硫技术进行金属硫化矿的内因火灾防治具有可行性。     

黑麦草根际强化微生物净化甲苯

采用在普通生物反应器上种植黑麦草的方法,研究了黑麦草根系强化微生物净化甲苯污染气体的作用,及甲苯入口浓度、填料深度、温度对反应器净化甲苯速率的影响。结果表明,在生物反应器相同的填料深度,细菌数量的水平分布为黑麦草根际区>过渡区>非根际,与相同位置的甲苯浓度分布呈负相关,说明黑麦草根系通过促进细菌的活性进而增加甲苯的降解。在相同的甲苯入口浓度下,甲苯的净化速率随着填料深度的增加而增加,在甲苯入口浓度不高于500 mg/m3条件下,相同的填料深度,反应器对甲苯的净化速率随着甲苯浓度的增加而增加。在5~35℃范围内,温度升高有助于提高微生物活性,促进微生物对甲苯的降解,且有黑麦草处理的甲苯净化速率大于同等条件下无黑麦草处理。     

Respiration induced by substrate and bacteria diversity after application of diuron,hexazinone, and sulfometuron-methyl alone and in mixture

Abstract

After application, herbicides often reach the soil and affect non-target soil microorganisms, decreasing their population, diversity or affecting metabolic activity. Therefore, laboratory studies were performed to evaluate the effects of diuron, hexazinone and sulfometuron-methyl alone and mixed upon carbon transformation by soil microorganisms in clayey and sandy soils and the effect on bacterial diversity and structure. Control treatment without herbicide application was also performed. Sub-samples from the control and herbicide treatments (10?g – in triplicate) were collected before herbicide application and 7, 14, 28 and 42?days after treatment (DAT), then 1?mL of ¹⁴C-glucose solution was applied. The released ¹⁴CO₂ was trapped in 2?M NaOH solution and the radioactivity was analyzed by liquid scintillation counting (LSC), 12?h after glucose application. The effect of herbicides on bacterial diversity was evaluated by T-RFLP. The experiment was conducted in a complete randomized design. Hexazinone did not affect ¹⁴CO₂ evolution. Diuron showed a greater ¹⁴CO₂ evolution in sandy and clayey soil, while sulfometuron-methyl led to an increase in sandy soil, at 42 DAT. A greater evolution of carbon was observed in the treatment with herbicide mixture in sandy soil, compared with the same treatment in clayey soil or control. However, the herbicide mixture application did not affect the soil biological activity measured by the respiration rate induced by substrate. On the other hand, the herbicide mixtures affected the bacterial diversity in both soils, being the strongest effect to diuron and sulfometuron-methyl in clayey soil and hexazinone in sandy soil.     

环境DNA宏条形码监测湖泊真核浮游植物的精准性

环境DNA(eDNA)宏条形码(metabarcoding)技术是一种基于分子的生物多样性高效监测手段,近年来越来越多地被应用于生态环境中生物要素的监测和评估.开展eDNA 宏条形码监测技术的标准化和规范化研究,是将其业务化推广应用的前提.本研究以高原湖泊滇池和抚仙湖的真核浮游藻类为研究对象,探究了基于18 S-V9 ...     

低聚木糖作为调理剂对土壤微生物和酶的影响

针对集约化农业过量施入化肥农药等引起的土壤质量退化问题,采用造纸黒液废物提取的低聚木糖作为土壤调理剂。通过室内土壤培养,研究不同低聚木糖施用量(0.01%、0.05%、0.1%和0.2%)对土壤微生物数量和脲酶活性的影响。通过番茄盆栽实验,并设置添加0.1%商品生物有机肥处理作比较,研究不同低聚木糖施用量对土壤微生物量氮磷、脲酶和磷酸酶活性的影响。结果表明,低聚木糖可以提高土壤细菌、放线菌数量、土壤脲酶和磷酸酶活性。低聚木糖也显著增加番茄各生长期土壤微生物量碳和磷含量,其中开花期时低聚木糖的促进作用最为明显。所有剂量处理中,以0.05%的低聚木糖添加量处理效果最为明显,且该处理效果也优于添加0.1%生物有机肥处理。低聚木糖作为土壤调理剂,能显著提高土壤微生物数量和酶活性,改善土壤生态系统,提高土壤质量,在农业上具有广阔的应用前景。     

多孔矿物载体厌氧固定床处理有机废水研究

通过天然浮石和塑料多孔空心球而制成复合式多孔矿物载体应用于厌氧固定床反应器中,研究反应器挂膜性能,以及处理生活污水、啤酒废水效果,应用扫描电镜观察生物膜微生物相的形态结构.结果表明,反应器挂膜69 d后COD去除率稳定在70%以上,初次启动成功;处理生活污水中平均COD去除率为61.72%;处理啤酒废水中COD去除率高...     

含氰化物废水生物处理研究进展

综述了含氰化物废水的主要处理技术和存在的问题,探讨了微生物降解氰化物的生物化学途径以及生物降解机理.介绍了影响氰化物生物降解性能的因素和含氰化物废水的生物处理特点,综述了含氰化物废水生物处理的最新研究进展,并展望了微生物降解氰化物技术的发展趋势与应用前景.     

Identification of surfactants emerged in aerobic granulation

In this study, aerobic granules were cultivated in sequencing batch reactors with activated sludge as the seed. The reactors were operated for 12 h per cycle with the organic loading rate (OLR) increasing in double stepwise from 0.5 to 4.0 g COD L⁻¹ d⁻¹. Within the 40 d running, black granules with regular and smooth morphology were cultivated, which had high wet density and high settling velocity. During the granulation process, foams emerged and disappeared in the reactor, coinciding with the proliferation of filamentous microorganisms in the granules, implying that surfactants might exist and play an important role in the granulation. Using ultra performance liquid chromatography-tandem mass spectrometry, the surfactants were identified as homologous compounds of polyethylene glycol (PEG) with molecular weights ranging mainly from 100 to 500 Da. Their general formulas were proposed as HO-[CH₂-CH₂-O]_n-H. The source of PEG still needs further investigation.     

聚合酶链反应—变性梯度凝胶电泳技术研究梯田式人工湿地微生物群落动态变化

采用聚合酶链反应(PCR)—变性梯度凝胶电泳(DGGE)技术对梯田式人工湿地(TTCW)和复合垂直流式人工湿地(IVCW)生活污水处理系统内的微生物群落结构的动态变化及其对生活污水处理效果的影响进行了对比研究。结果表明:(1)TTCW和IVCW对生活污水均具有较好处理效果,其COD去除率平均分别为76.2%和72.6%、TP去除率平均分别为90.7%和85.6%、NH4+-N去除率平均分别为65.2%和58.8%;TTCW增氧作用明显。(2)2种人工湿地内均存在丰富的微生物群落,并均存在共有的微生物种群;在湿地沿程不同位置均存在一定数量的优势种群。(3)TTCW强化了大气复氧能力,使得湿地内DO较相同深度的IVCW的高。TTCW具有较强的污染物去除能力,特别是具有高效的脱氮除磷能力。这种能力可能主要是TTCW中微生物群落结构的变化所致。     

固定化微生物技术在废气处理中的研究进展

介绍了固定化微生物的制备方法和载体选择,综述了国内外采用固定化微生物技术处理各种废气的研究和应用现状,并提出了固定化微生物技术进一步发展的方向。