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61.
以液体石蜡为碳源,对采油菌株Bacillus FH-1-2进行好氧和兼性厌氧培养。通过测定培养过程中发酵液的表面张力、菌体密度、pH值以及细胞疏水性,发现好氧和兼性厌氧培养过程中各项指标的变化趋势相近,兼性厌氧条件下的生长较慢;细胞疏水性和发酵液pH值均无显著变化;发酵液接近中性,有利于菌体生长。结果表明,细胞疏水性强能促进菌体生长。对数生长期发酵液的表面张力随菌体密度的增大而减小,在菌体生长的稳定期和衰亡期,发酵液的表面张力和菌体密度正相关。兼性厌氧培养更有利于菌株Bacillus FH-1-2应用于原油采收。 相似文献
62.
研究了异养菌和自养菌颗粒污泥的特性:与异养菌相比,自养菌颗粒污泥粒径小、密度大、胞外多聚物(EPS)含量高但强度小。通过对粒径、EPS等特性与密度的变化规律分析,研究发现,自养菌颗粒污泥的粒径与密实度呈现出一致性,颗粒趋于稳定;而异养菌颗粒污泥粒径成长同时伴随着密度减小,粒径与密实度呈现不一致性,颗粒容易解体。颗粒强度的分析结果表明:在自养菌系统中EPS与孔隙率能够达到动态平衡是其长期维持稳定的主要原因,而异养菌中粒径与孔隙率无法达到平衡,操作条件无法控制高强度丝状菌的繁殖是其不稳定的主要因素。 相似文献
63.
产共轭亚油酸乳酸菌的选育和鉴定 总被引:1,自引:0,他引:1
采用紫外分光光度法测定共轭亚油酸的含量,从13株实验室保存的乳酸菌中筛选出8株具有转化亚油酸生成共轭亚油酸能力的菌株.其中As1.2686产量最高,发酵液中共轭亚油酸含量达到13.63 mg/L;其次是菌株B11693,共轭亚油酸产量为11.55 mg/L.选择B11693做进一步的菌种鉴定,将传统的形态学、生理生化鉴定方法和细菌16SrDNA分子生物学鉴定方法相结合,鉴定菌株B11693为短乳杆菌. 相似文献
64.
固定化细胞技术和基因工程技术在环境污染物治理领域是新兴技术。本文综述了近年来固定化细胞技术和基因工程技术在水环境污染治理中的研究及应用情况。通过固定化基因工程菌处理废水的一系列成功实验,表明了其在废水好氧反硝化等水环境污染治理中的广阔应用前景。 相似文献
65.
To achieve stable and efficient nitrogen and phosphorus removal and to investigate the characteristics of the A/A SBR enriched with denitrifying phosphorus removal bacteria(DPB),the whole course of startup was studied with two reactors operated in different mode.The reactor I was operated under anaerobic/settling/anoxic/settling mode,and the reactor II was operated under anaerobic/anoxic/settling mode.Differences between the two reactors in removal efficiency of COD,nitrogen and phosphorus were examined.The results indicated that efficient performance could be achieved in both reactors with different startup operation mode,while the phosphorus removal efficiency was improved sooner in reactor I than in reactor II,which suggested that reactor I would supply a more favorable condition for DPB proliferation.Meanwhile,it was observed that the amount of organic substrates consumption had a linear correlation to that of phosphorus release in anaerobic phase when DPB was accumulated in the A/A SBR denitrifying phosphorus removal system. 相似文献
66.
The high-active bacteria were screened from 8 dominant bacteria obtained from the natural water body,and then the bioaugmentation activated carbon was formed by hydraulic immobilization of the high-active bacteria. Plant-scale studies on removal characteristics of disinfection by-products formation potentials (DBPFP) by bioaugmentation activated carbon process were conducted for micro-polluted raw water treatment. The results show that the bioaugmentation activated carbon process has adopted better purification efficiency to THMFP and HAAFP than traditional biological activated carbon process,and that average removal efficiencies of THMFP and HAAFP can reach 35% and 39.7% during the test period,increasing by more than 10% compared with traditional biological activated carbon process. The removal efficiencies of THMFP and HAAFP are stable because of the biodegradation of the high-active bacteria and the adsorption of active carbon. The biodegradability of CHCl3 formation potential is better as compared with that of CHCl2Br and CHClBr2 formation potentials among THMFP,and high removal efficiency of CHCl3formation potential is obtained by bioaugmentation degradation of the high-active bacteria. The biodegradability of HAAFP is better in comparison with that of THMFP,and the chemical properties of HAAFP are propitious to adsorption of activated carbon. Thus,HAAFP is on predominance during the competitive removal process with THMFP. 相似文献
67.
为了有效控制A/O生物除磷工艺处理化粪池污水时产生的丝状菌膨胀,先后采取改变系统的COD污泥负荷(NCOD)、溶解氧(DO)的质量浓度和降低S2-的质量浓度等措施,最终使A/O除磷工艺丝状菌膨胀得到了控制,污泥沉降性能得到了有效恢复.研究结果表明:A/O除磷工艺在高NCOD条件下运行时,容易发生严重的丝状菌膨胀现象,原因是COD在厌氧区降解后仍有较高的剩余量进入好氧区,导致聚磷菌在和丝状菌的竞争中优势变弱;在低NCOD条件下运行时,由于原水中硫化物含量过高导致丝状硫细菌增殖,因此仍然存在轻度的丝状菌膨胀现象. 相似文献
68.
一株枯草芽孢杆菌分离鉴定及其降解稠油特性 总被引:4,自引:1,他引:3
以稠油为唯一碳源,从被稠油污染过的土壤中筛选到一株高效石油烃降解茵,经生理生化鉴定和16S rDNA鉴定确认其为枯草芽孢杆茵.在摇瓶实验中,该菌最佳降解温度为35~45℃,最佳pH值为7.5~8.5,最佳盐质量浓度为8~16 g/L.在最佳降解条件下,当油质量浓度为0.1 g/L时,稠油降解率达34.3%.利用GC-nD分析知,该茵主要降解稠油中n-C9~n-C40的烷烃组分;利用GC-MS分析得知,该茵对蔡及烷基化萘去除彻底,对二苯并噻吩、芴和稠二萘等部分芳烃类化合物有降解作用,在稠油降解过程中菲及菲的衍生物有所增加. 相似文献
69.
A sulfate reducing bacteria was isolated from mining sewage of Daqing Oilfield by Hungate anaerobic technology. Physiological-biochemical analysis showed that the strain could utilize polyacrylamide as sole carbon and nitrogen source. The sequence analysis of 16S rDNA illustrated that the similarity of F8 and Desulfovibrio desulfuricans (AF192153) was 99%, and the similarity sequence of dissimilatory sulfite reductase gene (DSR) cloned from the strain and Desulfovibrio desulfuricans (AF273034) was 98%. Their phylogenitic analysis was basically anastomosed, and thus temporarily named as Desulfovibrio desulfuricans F8. The DSR cloned from F8 strain was 2740 bp in length consisting of three ORF, DSRA, DSRB and DSRD as a single operon (DSRABD) regulated by the same operator. DSRA contained typical conservative box of sulfate—sulfite reducing enzyme (SiteⅠand SiteⅡ), which could bind siroheme and [Fe4S4]. DSRB retained a [Fe4S4] binding site, with an uncomplimentary structure for siroheme binding. There was no conservative box in DSRD. Sequence analysis of DSR will provide a theoretical basis for quantitative detection, metabolic pathway modification through gene engineering, and sulfate reducing bacteria (SRB) suppression. 相似文献
70.
从淮北焦化厂A2/O污水处理站二沉池的活性污泥中,采用焦化废水配制的牛肉膏蛋白胨固体培养基(DM100)分离纯化出7株反硝化细菌,并通过梯度添加焦化废水的平板驯化和液体驯化,在DO=2.5 mg/L的条件下复筛出4株具有抗逆性的优势好氧反硝化细菌,分别命名F4、F8、F9、F10.优势单菌株与组合菌群反硝化能力的对比试验表明,4株混合的好氧反硝化菌群生长快速稳定,在相同的试验条件下脱氮效率高于单菌株,48 h的NO3--N去除率为98.75%.4株混合菌群的最适生长条件为:35℃,pH=8.0,C/N比=5,接种量=25%(菌液浓度为(2~3)×107个/mL).经过筛选和条件优化,优势菌群NO3--N去除率达到90%的降解时间由96 h降到18 h. 相似文献