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951.
JSP技术及其在安全管理信息系统中的应用 总被引:4,自引:2,他引:4
基于B/S模式并结合JSP(JavaServerPagesTM)技术 ,实现省、市职能部门对企业安全生产监督管理及安全信息共享平台。政府职能部门能够及时监管各地安全动态、发布公告和指令、校验特种作业人员和注册安全主任资格等 ;用户能进行事故隐患和执法监督行为投诉、事故快报、安全技术咨询、地方或行业法规标准查询等活动。从而 ,达到构建安全管理、安全技术服务、安全信息发布、事故预防集成系统的目的。 相似文献
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采用富集培养法从污水厂活性污泥中分离得到一株能以邻苯二甲酸二(2-乙基己基)酯(DEHP)为唯一碳源的细菌。该菌在48 h内可将DEHP浓度从20 mg/L降解到2 mg/L。对其进行了生理生化试验和分子生物学鉴定。结果表明,该菌株呈丝状,革兰氏阳性,好氧,能在45℃下生长。该菌株与长孢糖丝菌模式菌Saccharothrix longispora DSM 43749在同一分枝上,同源性为98.9%;与糖丝菌属(Saccharothrixsp)内其他种同源性均在97.0%以上。 相似文献
954.
利用自由基与乙醇和叔丁醇之间反应速率差异,研究在不同条件下Cu2+/Na2S2O8体系中产生自由基的状况.实验研究表明:Na2S2O8体系会产生·OH和SO-4由于Cu2+的催化作用,使用Cu2+Na2S2O8体系比单独使用Na2S2O8能产生更多的自由基·OH和SO-4.研究还发现:pH值降低能促进Na2S2O8分解产生自由基,但是会抑制SO-4转化为·OH;温度升高,Na2S2O8分解产生的·OH和SO-4均增加. 相似文献
955.
Denitrification characteristics of a marine origin psychrophilic aerobic denitrifying bacterium 总被引:3,自引:0,他引:3
Haiyan Zheng Ying Liu Guangdong Sun Xiyan Gao Qingling Zhang Zhipei Liu 《环境科学学报(英文版)》2011,23(11):1888-1893
A psychrophilic aerobic-denitrifying bacterium was isolated, identified as Psychrobacter sp., and characterized, it performed efficient aerobic-denitrification at low temperature and might be useful in nitrogen removal treatment for low temperature wastewater. 相似文献
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Most of the oxalotrophic bacteria are facultative methylotrophs and play important ecological roles in soil fertility and
cycling of elements. This study gives a detailed picture of the taxonomy and diversity of these bacteria and provides new
information about the taxonomical variability within the genus Methylobacterium. Twelve mesophilic, pink-pigmented, and facultatively methylotrophic oxalate-oxidizing strains were included in this work
that had been previously isolated from the soil and some plant tissues by the potassium oxalate enrichment method. The isolates
were characterized using biochemical tests, cellular lipid profiles, spectral characteristics of carotenoid pigments, G+C
content of the DNA, and 16S rDNA sequencing. The taxonomic similarities among the strains were analyzed using the simple matching
(S
SM) and Jaccard (S
J) coefficients, and the UPGMA clustering algorithm. The phylogenetic position of the strains was inferred by the neighbor-joining
method on the basis of the 16S rDNA sequences. All isolates were Gram-negative, facultatively methylotrophic, oxidase and
catalase positive, and required no growth factors. Based on the results of numerical taxonomy, the strains formed four closely
related clusters sharing ≥85% similarity. Analysis of the 16S rDNA sequences demonstrated that oxalotrophic, pink-pigmented,
and facultatively methylotrophic strains could be identified as members of the genus Methylobacterium. Except for M. variabile and M. aquaticum, all of the Methylobacterium type strains tested had the ability of oxalate utilization. Our results indicate that the capability of oxalate utilization
seems to be an uncommon trait and could be used as a valuable taxonomic criterion for differentiation of Methylobacterium species. 相似文献
959.
Purification of total DNA extracted from activated sludge 总被引:2,自引:0,他引:2
Purification of the total DNA extracted from activated sludge samples was studied. The effects of extraction buffers and lysis treatments (lysozyme, sodium dodecyl sulfate (SDS), sonication, mechanical mill and thermal shock) on yield and purity of the total DNA extracted from activated sludge were investigated. It was found that SDS and mechanical mill were the most effective ways for cell lysis, and both gave the highest DNA yields, while by SDS and thermal shock, the purest DNA extract could be obtained. The combination of SDS with other lysis treatment, such as sonication and thermal shock, could apparently increase the DNA yields but also result in severe shearing. For the purification of the crude DNA extract, polyvinyl polypyrrolidone was used for the removal of humic contaminants. Cetyltrimethyl ammonium bromide, potassium acetate and phenol/chloroform were used to remove proteins and polysaccharides from crude DNA. Crude DNA was further purified by isopropanol precipitation. Thus, a suitable protocol was proposed for DNA extraction, yielding about 49.9 mg (total DNA)/g volatile suspended solids, and the DNA extracts were successfully used in PCR amplifications for 16S rDNA and 16S rDNA V3 region. The PCR products of 16S rDNA V3 region allowed the DGGE analysis (denatured gradient gel electrophoresis) to be possible. 相似文献
960.
The effects of Cd^2+ and Cu^2+ at 300 mg/L on anaerobic microbial communities that degrade 2-cholorophenol (2-CP) were examined. Based on the polymerase chain reaction (PCR) of 16S rDNA, bacterial community diversity and archaeal community structure were analyzed with denaturing gradient gel electrophoresis (DGGE) and cloning, respectively. Degradation capabilities of the anaerobic microbial community were drastically abated and the degradation efficiency of 2-CP was reduced to 60% after shock by Cu^2+ and Cd^2+, respectively. The bacterial community structure was disturbed and the biodiversity was reduced after shock by Cu^2+ and Cd^2+ for 3 d. Some new metal-resistant microbes which could cope with the new condition appeared. The sequence analysis showed that there existed common Archaea species in control sludge and systems when treated with Cu^2+ and Cd^2+, such as Methanothrix soehngenii, Methanosaeta concilii, uncultured euryarchaeote, and so on. Both the abundance and diversity of archaeal species were altered with addition of Cd^2+ and Cu^2+ at high concentration. Although the abundance of the predominant archaeal species decreased with Cd^2+ and Cu^2+ addition for 3 d, they recovered to some extent after 10 d. The diversity of archaeal species was remarkably reduced after recovery for 10 d and the shift in archaeal composition seemed to be irreversible. The 2-CP-degradation anaerobic system was more sensitive to Cu^2+ than Cd^2+. 相似文献