重金属抗性菌Bacillus cereus HQ-1对银离子的生物吸附-微沉淀成晶作用

发现1株对银离子有强吸附能力的蜡状芽孢杆菌HQ-1,研究了其对银离子的吸附特性及吸附机理.结果表明,菌体对银的吸附量可达91.75 mg/g,吸附过程符合Pseudo-second Order吸附动力学模型,相关系数高达0.999 9;吸附热力学很好地符合Freundlich吸附等温模型,相关系数为0.99;考察菌体浓度和温度对吸附的影响发现,菌体浓度增加有利于对银离子的吸附,温度对吸附影响较小;FTIR、SEM及EDAX实验结果表明吸附存在2种吸附机理,一为菌体表面一些含氮氧的基团对Ag⁺的络合作用,二为菌体分泌的胞外多糖等物质对Ag⁺的微沉淀成晶作用.     

一株好氧反硝化细菌的分离鉴定及反硝化能力

利用驯化活性污泥的方法筛选出一株好氧反硝化细菌G3,该菌在碳源充足且溶解氧为(4.0±1.0)mg·L-1条件下,24h内对NO-2-N积累量为12.03 mg·L-1,对NO-3-N的去除率为91.09%.扫描电镜观察其形态特征为(0.4～0.6)μm×(1.2～2.0)μm的短杆菌.16SrDNA序列分析表明,该菌与Pseudomonas stutzeri的相似性为100%.利用MEGA软件对该菌株与已报道的相关微生物进行系统发育分析,并克隆出与好氧反硝化相关的周质硝酸盐还原酶的亚基napA基因,初步判定筛选菌株具有周质硝酸盐还原酶.     

Impact of acetochlor on ammonia-oxidizing bacteria in microcosm soils

Acetochlor is an increasingly used herbicide on corn in North China. Currently, the effect of acetochlor on soil ammonia-oxidizing bacteria (AOB) communities is not well documented. Here, we studied the diversity and community composition of AOB in soil amended with three concentrations of acetochlor (50, 150, 250 mg/kg) and the control (0 mg acetochlor/kg soil) in a microcosm experiment by PCR-DGGE (polymerase chain reaction-denaturing gradient gel electrophoresis) and the phylogenetic analysis of excised ...     

Decomposition of hexachlorobenzene over Al2O3 supported metal oxide catalysts

Decomposition of hexachlorobenzene(HCB)was investigated over several metal oxides(i.e.,MgO,CaO,BaO,La2O3,CeO2,MnO2, Fe2O3,and Co3O4)supported on Al2O3,which was achieved in closed system at a temperature of 300°C.Catalysts were prepared by incipient wetness impregnation with different metal oxides loading and impregnating solvents.The decomposition effciency of different catalysts for this reaction depends on the nature of the metal oxide used,and Al2O3 supported La2O3 was found to be the most active one.Pe...     

固定化与游离态小球藻脱氮除磷对比研究

对固定化与游离态小球藻脱氮、除磷进行对比研究,结果表明固定化藻在2d内对NH4^＋-N和PO^3-4-P的净化效率比悬浮态藻分别高23.14％和35.19％。固定化后初期会对藻细胞的生长产生影响,使得固定化藻的数量增长慢于悬浮态藻的生长,但在较短时间（24a左右）内细胞的活性即可恢复,并保持持续生长,这说明固定化没有对细胞产生不可恢复的损伤。固定化藻技术不仅保留了悬浮态藻的优点,而且使得藻对氮、磷的去除率有较大提高,对藻细胞起到了保护作用,延长藻细胞的生长期,有利于细胞更多地吸收氮、磷。     

矿山污染控制与生态恢复进展研究

通过分析矿山开采过程对矿山区域造成的主要环境污染问题,总结国内外最新的矿山污染控制措施,阐述了矿山生态恢复的理论研究与实践现状.在综合国内外矿山污染控制与生态恢复两方面的研究与实践经验的基础上,提出了矿山污染控制与生态恢复研究的发展展望.     

推动环境工程在型号中应用探讨

阐述了当前在型号中开展环境工程工作的紧迫性,并从认识角度、工作机制、数据应用、关键技术和标准支撑等方面提出了进一步推动环境工程在型号中应用的构想.     

一种粪便污染源识别新技术——微生物源示踪

为了应对人畜粪便对水域环境污染日益加重且久治无效的局面,始于美国90年代初的一种能够识别污染水体中粪便污染源的新的监测技术MST被提出.如今该技术已成为一些欧美国家水域环境管理的有力工具,而我国关于MST技术的研发刚刚起步.本文简要介绍MST技术的基本原理,并着重阐述该技术的方法学,进而预测MST技术的未来发展趋势,以期为同领域专家学者提供参考,促进MST技术在我国的应用.     

Effect of rhizosphere on soil microbial community and in-situ pyrene biodegradation

To access the influence of a vegetation on soil microorganisms toward organic pollutant biogegration, this study examined the rhizospheric effects of four plant species (sudan grass, white clover, alfalfa, and fescue) on the soil microbial community and in-situ pyrene (PYR) biodegradation. The results indicated that the spiked PYR levels in soils decreased substantially compared to the control soil without planting. With equal planted densities, the efficiencies of PYR degradation in rhizosphere with sudan grass, white clover, alfalfa and fescue were 34.0%, 28.4%, 27.7%, and 9.9%, respectively. However, on the basis of equal root biomass the efficiencies were in order of white clover >> alfalfa > sudan > fescue. The increased PYR biodegradation was attributed to the enhanced bacterial population and activity induced by plant roots in the rhizosphere. Soil microbial species and biomasses were elucidated in terms of microbial phospholipid ester-linked fatty acid (PLFA) biomarkers. The principal component analysis (PCA) revealed significant changes in PLFA pattern in planted and non-planted soils spiked with PYR. Total PLFAs in planted soils were all higher than those in non-planted soils. PLFA assemblages indicated that bacteria were the primary PYR degrading microorganisms, and that Gram-positive bacteria exhibited higher tolerance to PYR than Gram-negative bacteria did.     

规划方案下清洁发展机制介绍与评价

规划方案下清洁发展机制（PCDM）,作为完善现有清洁发展机制（CDM）而提出。PCDM通过形成规模效益,推动社会向低碳经济转型,并进一步为发展中国家参与CDM提供机会,PCDM的改进最突出的体现于对技术转让的设计上。因此,本文在简要介绍PCDM的基础上,对PCDM分析评价。提出如何选择适合开发PCDM领域,并指出PCDM在技术引进中的作用。