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101.
脱氮硫杆菌的生态特性及其应用 总被引:3,自引:0,他引:3
介绍了脱氮硫杆菌的生态特性与适宜的生长条件。说明了脱氮硫杆菌在地球元素循环中的地位与作用。向浅层油藏中添加硝酸盐和磷酸盐,能够刺激其中的脱氮硫杆菌大量增殖,抑制H2S的生成,消除FeS造成的堵塞,减轻管材的腐蚀。以硫磺为电子供体,石灰石作碳源和平衡碱度,脱氮硫杆菌接种的反应器用来脱除饮用水和地下水中的硝酸盐,可获得98%以上的脱除率,但易引起SO4^2-和硬度超标,若将其与其它反硝化方法集成使用则可克服这一缺陷。用脱氮硫杆菌在碱性条件下脱除天然气中的H2S亦能获得良好的效果。 相似文献
102.
从云南某铜矿井下酸性污水中分离到嗜酸菌株ynxd-1,对其形态、生长特性、16 S rRNA基因序列及其对低品位硫化镍铜矿的摇瓶浸出效果进行了研究.结果表明:细菌细胞呈短杆状,革兰氏染色阴性,不产芽孢,最适pH值及生长温度分别为2.0和30℃.菌株ynxd-1在10%(W/V)矿浆浓度及30℃温度的条件下摇瓶培养浸出28 d,低品位硫化镍铜矿镍的浸出率为56.4%.16 S rRNA基因序列分析表明,菌株ynxd-1与嗜酸氧化亚铁硫杆菌的同源性达到99%,可以鉴定为嗜酸氧化亚铁硫杆菌菌株. 相似文献
103.
In S Kim Jong‐Un Lee Am Jang 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(12):1339-1348
The feasibility of bioleaching for removal of heavy metals from dewatered sewage sludge using an iron‐oxidizing bacterium Acidithiobacillus ferrooxidans was investigated. The influence of seven process parameters including cell adaptation, total amount and particle size of the sludge, initial concentrations of Fe2+ and At ferrooxidans, and addition of inorganic nutrients and sulfur were evaluated in terms of the solubilization of Zn, Cu and Cr. When sludge‐adapted cells, addition of inorganic nutrients and lower sludge content were involved, higher yields of metal extraction were obtained. However, higher initial concentrations of At ferrooxidans and Fe2+, fine particle size of the sludge and S addition did not improve the metals' solubilization during an experimental period of 7 days. As a result of a long‐term (40 days) bioleaching experiment, 42% of Zn (1300–1648 mg kg?1), 39% of Cu (613–774 mg kg?1) and 10% of Cr (37–44 mg kg?1) in the sludge were leached into the solution. The results indicate that a bioleaching process conducted under operationally optimal conditions can be effectively employed for the removal of heavy metals from sewage sludge before land application. Copyright © 2005 Society of Chemical Industry 相似文献
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106.
ShaoxianSong YiminZhang ShouciLu 《北京科技大学学报(英文版)》2004,11(5):385-388
Bioflotation of pyrite with bacteria Thiobacillus ferrooxidans in the presence or absence of potassium ethyl xanthate was studied on a pure pyrite through microflotation and electrophoretic light scattering measurements. The experimental results showed that in the absence of xanthate, pyrite flotation is slightly enhanced by Thiobacillusferrooxidans. However, with xanthate as a collector, pyrite flotation is strongly depressed after being exposed to the bacteria. The longer is the time when the pyrite is exposed to the bacteria, the stronger the depression is. The mechanism of the depression might be due to the formation of the biofilms of Thiobacillus ferrooxidans on pyrite surfaces, preventing the adsorption of xanthate on pyrite surfaces in the form of dixanthogen or xanthate ions. 相似文献
107.
1INTRODUCTION Thefeatureofmineralsurfaceismodifiedlike thecellsurfacebyfixingbacteriaonitssurface whilethefeatureofcellsurfaceisdeterminedbyits livingcondition[1].Thecomponentofbacterial surfaceplaysanimportantroleinthebacterialat tachmentonminerals[2,3].Itisprovedthatcell wallandoutermembraneareinvolvedintheadhe sionbetweenmineralsandmicrobes,whilethein nermembraneandotherorganelleshardlyhaveany influenceonthisprocess.Thesephysiological structuresofbacteria,especiallytheoutermem brane,af… 相似文献
108.
The gene sod in Acidithiobacillus ferrooxidans may play a crucial role in its tolerance to the extremely acidic, toxic and oxidative environment of bioleaching. For insight into the anti-toxic mechanism of the bacteria, a three-dimensional (3D) molecular structure of the protein encoded by this gene was built by homology modeling techniques, refined by molecular dynamics simulations, assessed by PROFILE-3D and PROSTAT programs and its key residues were further detected by evolutionary trace analysis. Through these procedures, some trace residues were identified and spatially clustered. Among them, the residues of Asn38, Gly103 and Glu161 are randomly scattered throughout the mapped structure; interestingly, the other residues are all distinctly clustered in a subgroup near Fe atom. From these results, this gene can be confirmed at 3D level to encode the Fe-depending superoxide dismutase and subsequently play an anti-toxic role. Furthermore, the detected key residues around Fe binding site can be conjectured to be directly responsible for Fe binding and catalytic function. 相似文献
109.
The formation of jarosite in the presence of Acidithiobacillus ferrooxidans (A. ferrooxidans) was researched to ascertain the conditions of producing minimum precipitation. The effects of salt concentration and pH on the characteristics of jarosite formed in K2SO4/(NH4)2SO4-FeSO4 inorganic salt solution and 9K medium were studied by using the measurements of scanning electron microscope, X-ray diffraction, Fourierism transform infrared analysis, thermogravity/differential thermogravity analysis and particle size analysis to evaluate the product. The results indicate that the formation of jarosite begins when A. ferrooxidans reaches logarithmic growth phase in 9K medium, and a higher pH value is beneficial to the formation of jarosite. The jarosite formed in 9K medium has smaller and more concentrative particle size and smoother surface than that formed in inorganic salt solution. 相似文献
110.
氧化亚铁硫杆菌分离复壮的研究 总被引:4,自引:0,他引:4
用稀释涂布平板法从已退化的氧化亚铁硫杆菌菌液中分离出氧化活性较高,生命力强的氧化亚铁硫杆菌T1,对其菌落,细胞形态和生长特性进行了初步研究,结果表明其最适生长条件为培养温度30℃,pH=2.0,分离出的T1菌株氧化活性是分离前菌株氧化活性的1.2倍。 相似文献