磁性载体固定化机油降解菌FZ5的研究

利用聚乙烯醇-海藻酸钠-磁性竹炭复合制备磁性悬浮小球，该小球的磁矫顽力为28.6 mT，具有较强的磁场，可用于磁场引导分离。利用磁性悬浮小球作为载体对机油降解菌FZ5进行固定化，研究了固定化时间、降解时间、固定化小球投加量、初始pH值和初始机油浓度对机油降油率的影响。结果表明，在固定化挂膜3 d，固定化小球投加量为8％，初始pH值为7，初始机油浓度为400 mg/L，降解培养3 d后对机油的降解率可达91.21％。     

海藻酸钠与纳米Fe_3O_4联合固定化菌对三氟羧草醚的降解

采用联合固定化技术,将菌株Pseudomonas citronellolis DK-3与纳米Fe_3O_4固定于海藻酸钠小球中制成纳米Fe_3O_4和海藻酸钠联合固定化菌(Fe_3O_4/SA),并系统研究了纳米Fe_3O_4的最佳投加量,Fe_3O_4/SA联合固定化菌对三氟羧草醚的降解特性以及Fe_3O_4/SA固定化菌在序批式反应器(SBR)中的降解稳定性。实验结果表明,当纳米Fe_3O_4的投加量为90 mg·L~(-1),三氟羧草醚初始浓度为100 mg·L~(-1)时,固定化菌的降解率达到97.9%。扫描电镜结果表明Fe_3O_4/SA联合固定化小球更适合三氟羧草醚降解菌的附着生长。Fe_3O_4/SA联合固定化菌降解三氟羧草醚的最佳环境条件为pH:7~8、温度:30℃。此外,与SA固定化菌相比,Fe_3O_4/SA联合固定化菌具有更强的耐环境因素变化能力,抗重金属离子毒性能力。并且,经多次重复使用后,联合固定化菌仍保持较高的降解率(95%)。最后,实验室规模序批式反应器(SBR)中降解实验表明,Fe_3O_4/SA联合固定化菌能够稳定运行35 d以上,降解率均高于95%,为三氟羧草醚固定化细菌的工程化应用奠定了理论基础。     

蒽的高效降解菌的固定化小球的制备及其降解特性

旨在利用固定化高效降解菌小球去除水中蒽,充分发挥累托石的吸附和生物降解的协同作用,以累托石、聚乙烯醇(PVA)、海藻酸钠(SA)作为固定化载体材料,硼酸和氯化钙作为交联剂,将蒽的高效降解菌包埋制备固定化微生物小球.考察了累托石用量、PVA投加量、海藻酸钠用量、氯化钙用量、微生物包埋量和交联时间等因素对微生物小球活性的影响,通过正交实验确定了微生物小球的最佳制备条件.结果表明,制备固定化微生物小球的最佳条件为:累托石2.5%,PVA 12%,SA 0.3%,CaCl24%,交联时间28 h,微生物包埋量10%.对40 mgJ/L的蒽溶液,游离微生物在50 h后开始发挥明显的降解作用,经过68 h蒽的去除率达到35.65%;而固定化微生物小球经过9 h即可使蒽的去除率达到81.8%,23 h后葸的去除率可达100%.固定化微生物小球对水中蒽的去除机理与吸附-降解工艺的机理类似,即固定化微生物小球类似于一个一体化的微型反应器,经过迟滞期后,在该反应器内同时发生吸附和降解作用.     

固定化氨氮降解菌处理氨氮废水的试验研究

考察了海藻酸钠(SA)和聚乙烯醇(PVA)含量对固定化载体性能的影响,并筛选了最优条件制备固定化氨氮降解菌,研究其对氨氮废水的处理效果。当PVA和SA质量分数分别为8.00%、1.00%时,制成的固定化载体抗压性能最好,能够形成丰富的多孔结构。固定化氨氮降解菌在处理氨氮废水前驯化168h,可以恢复较高活性。在固定化氨氮降解菌投加量2%(质量分数)、反应温度30℃、pH 8.01、溶解氧3.0 mg/L的条件下反应60h,氨氮废水中的氨氮质量浓度从最初的3 835.29 mg/L降为82.35mg/L,去除率为97.85%。固定化氨氮降解菌在投加量低于氨氮降解菌的情况下,仍然能实现与之相近的氨氮废水处理效果,证明固定化氨氮降解菌能高效处理高浓度氨氮废水。     

聚乙烯醇-海藻酸钠固定铜绿微囊藻对磷的吸附

利用聚乙烯醇与海藻酸钠固定包埋铜绿微囊藻,通过正交实验获得聚乙烯醇溶液浓度、海藻酸钠溶液浓度及铜绿微囊藻液量去除磷的最佳配比,研究溶液起始pH值、反应时间、磷初始浓度对固定化小球吸附磷的影响。结果表明,固定化小球的最佳制备条件为聚乙烯醇质量分数6%,海藻酸钠质量分数0.5%及铜绿微囊藻浓度2×107个/mL;固定化小球吸附磷的最适起始pH值为6～8,吸附达到平衡的时间为9～12 d,初始磷浓度为1.00 mg/L时去除率最高,达到79.19%。     

高岭土固定GY2B优化其降解性能

以高岭土为负载材料分别用吸附和包埋2种方法固定GY2B优化其降解苯酚的性能。结果显示,采用吸附固定法,高岭土投加浓度为20 g/L时效果最佳,苯酚降解效率相比游离GY2B提升约10%,降解时间由12 h缩短至6 h。包埋法当固定化小球组分投加为高岭土1%(m/v)、聚乙烯醇10%(m/v)、海藻酸钠0.3%(m/v)、GY2B菌悬液10%(v/v)时降解效果最佳,相比游离菌降解效率提升约14%,降解时间缩短至6 h。2种固定方式与游离菌相比均可提升苯酚的降解效果,其中包埋法效果更优,具有更大的适用推广前景。     

固定化小球藻与活性污泥的共生系统处理含锌废水

研究固定化小球藻与活性污泥的共生系统对含锌废水中Zn2+的去除效果,分析菌藻状态、初始Zn2+浓度、pH、固定化菌藻小球投加量和菌藻体积比等5个因素对固定化菌藻共生系统去除Zn2+的影响。结果表明,固定化活性污泥、固定化小球藻和固定化菌藻对Zn2+的去除效果均优于悬浮小球藻,其中固定化菌藻对Zn2+的去除效果最好;废水中初始Zn2+浓度小于100 mg/L时,固定化菌藻系统对废水中Zn2+的去除率达到90.5%;固定化菌藻系统去除废水中Zn2+的最佳条件是:初始Zn2+浓度为80 mg/L,pH=7,固定化小球投加量为80 mL,菌藻体积比为1∶2。     

吸附融合菌的固定化及对铬吸附特性研究

研究了融合菌的固定化方法及吸附特性,结果表明:1.5%海藻酸钠为包埋剂包埋50 g/L融合菌可制成物理和吸附性能较好的固定化吸附剂;40 g/L(约含5 g/L融合菌)的固定化吸附剂对30 mg/L含Cr废水的去除率可达94.54%;当投加量为50 g/L(约含6 g/L融合菌)时,固定化吸附剂可完全去除实际电镀废水(pH:2.67,Cu:1.70 mg/L,Cr:20.62 mg/L,N i:29.97 mg/L,Zn:1.11 mg/L)中的Cu和Cr,且对N i和Zn的去除率也分别达到了48.05%和61.09%;吸附过程符合准二级吸附动力学模型;填充柱工艺适用于固定化吸附剂连续处理含铬废水,当流速为150 mL/h和250 mL/h时填充柱一次稳定处理水量分别为7.2 L和11.5 L,且延长水力停留时间可提高出水水质。     

沙雷氏苯酚降解菌固定化条件优化及降解性能研究

从首都钢铁集团焦化厂曝气池中的活性污泥中分离出一株沙雷氏菌属,利用聚乙烯醇(PVA)-卡拉胶混合载体对该菌种进行固定化,并对实际焦化废水进行降解。结果表明:(1)以PVA为包埋材料,添加卡拉胶为辅助载体后,使得固定化苯酚降解菌小球在制备过程中不易出现凝集的现象,易于操作,固定化苯酚降解菌小球颗粒综合性能有所提高。(2)最佳的固定化条件:PVA质量分数为8%,卡拉胶质量分数为0.5%,KCl为0.4mol/L,菌体化包埋比(菌液和混合载体的体积比)为1.0∶5.0,固定化时间为24h。新制备的固定化苯酚降解菌在使用前需进行活化,以提高降解性能。(3)在焦化废水的实际降解中,固定化苯酚降解菌的降解性能明显优于游离苯酚降解菌,固定化的载体对固定于其中的菌种起到了保护作用。     

固定化生物活性炭处理糖蜜酒精废水

以预处理后的糖蜜酒精废液为培养基,从糖蜜酒精废液中筛选得到纯菌种,经鉴定,该菌种为黑曲霉组(Aspergillus niger group)。采用改性蔗渣灰活性炭包埋活体黑曲霉的方法制成固定化生物活性炭,以固定化小球为材料,糖蜜酒精废液为研究对象,通过单因素实验研究固定化小球降解预处理后的糖蜜酒精废水的实验条件。结果表明:当温度为22℃,pH为5,投加量为20 g·(50 mL)-1,培养8 d,固定化小球降解糖蜜酒精废液的效果最好,COD和色度的降解率分别达到92.90%和52.34%。     

Optimization of Height of Release of Air Pollutants

A number of key projects in the Environmental Protection Agency (EPA) particulate R&;D program having applicability to industry are presented. For electrostatic precipitators (ESP) there is presented the result of work on large diameter discharge electrodes which provide a decrease in penetration of up to a factor of 4 when compared to conventional small diameter electrodes. Also discussed is the multistage ESP which provides a collection efficiency that would require a collecting plate area 4 or 5 times larger with conventional ESP technology. The E-SOX technology makes use of the multistage concept to free up space in the ESP for SO₂ removals of up to 90%. Electrostatically augmented fabric filtration provides a reduction in pressure drop of about 5 0% as compared to conventional fabric filtration. Wind tunnel modeling of windbreaks for material storage piles indicates a potential for providing engineering design data that would allow significant emission reduction caused by wind erosion     

Investigation of the characteristics of the reflectivity of clouds

This paper investigates some of the reflectivity characteristics that clouds (when modelled as solid bodies) must exhibit to be compatible with observations that the reflecting surface of a cloud (i) appears almost equally bright across its face, (ii) is brightest when the cloud is opposite to the Sun but decreases in brightness as the cloud moves to other positions and (iii) increases in brightness with increasing optical thickness of the cloud in the observer's line of sight. These observations, respectively, are shown to imply that the peak value of the bidirectional total reflectivity from a cloud surface (i) increases in inverse proportion to the cosine of the angle between the Sun and the normal to the cloud surface, as the incident angle increases, (ii) appears to be directed back in the direction of the incident radiation, and (iii) increases as optical thickness of the cloud in the observer's line of sight increases. The results could have application in many fields (e.g. modelling diffuse radiance distributions for cloudy skies).     

次氯酸钠发生器的研制

介绍了电解法生产次氯酸钠的原理 ,并在原有生产工艺的基础上进行了重新设计和对设备的重新选择、改造 ,得出了各个工艺参数的最佳值 ,生产出高品质的次氯酸钠     

实验室质量管理体系内部审核的策划

在实施ISO／IEC 17025：1999标准《检测和校准实验室能力的通用要求》过程中，通过实验室质量管理体系内部审核的实践与系统分析，识别出内部审核策划阶段的关键环节，提出审核范围确定、审核计划和抽样方案制订的质量控制要求，为有序高效地实施内部审核提供了技术方法。     

Estimation of uncertainty of sampling for analysis of pesticide residues

Abstract

A computer model was used to take random samples from primary sample populations obtained from field trials to simulate the uncertainty of sampling for residue analysis of plant commodities and soil. The results indicate about 40%, 30% and 20% relative uncertainty when random samples of size 5, 10 and 25 are taken respectively, from a single lot. Therefore the sample size should be the same for establishing and enforcing legal limits.     

扬中生态环境建设的思考与实践

结合扬中生态环境的基本情况和存在的不足，进行了具体分析，对扬中未来生态建设的发展方向提出了建议及实施措施。     

Comparison of methods for evaluation of activity of photocatalytic films

Objective

This work aims to investigate the correlation between the photocatalytic activity determined by methylene blue bleaching (DIN 52980), stearic acid degradation, and degradation of acetone in gas phase.

Method

The photocatalytic TiO₂ coatings included in this investigation ranged from thin commercially available coatings (Activ^TM and BioClean^TM) and ready to use suspensions (Nano-X PK1245) to lab-produced PVD and sol?Cgel coatings. XRD analysis of the photocatalytic coatings showed that all the coatings consisted of nanocrystalline anatase, although the thickness and porosity varied considerably.

Results

The study showed that the reproducibility of the activity measurements was good. However, more importantly, the investigation showed that there is a good correlation between the activities determined by the different methods even though the characteristics of the photocatalytic coatings and the organic probe molecules varied considerably.

Conclusion

The overall findings of this work suggest that there is a good correlation between the investigated methods. These results are promising for the future work concerning standardization of methods for determination of the activity of photocatalytic films.     

Impact of overexploitation of shellfish: northeastern coast of India

India has a very extensive coastline of about 7515 km, rich in diverse living resources. These resources continue to deteriorate with rampant harvesting or are altered for other uses such as aquaculture and fisheries. The present paper deals with degrading coastal habitats in northeastern India, and projects the intensity of the stress arising from the collection of tiger prawn seeds (Penaeus monodon) for aquacultural farms and molluskan shells for poultry feed and edible lime. Indiscriminate exploitation of these resources leads to a heavy reduction of the species concerned and other associated marine communities. The magnitude of such destruction has been quantified. The impacts of biodiversity loss and their after-effects on the ecobalance of this coastal system have become a matter of great concern to ecologists to maintain security and sustainability. The authors propose a public awareness program on themes relating to the importance of biodiversity for human livelihoods.     

实验室质量管理体系内部审核的实施

在实施ISO／IEC17025：1999标准《检测和校准实验室能力的通用要求》过程中，通过实验室质量管理体系内部审核的实践与系统分析，识别出内部审核实施阶段的关键环节，提出召开首次会议、收集审核证据、确定审核发现和召开末次会议的技术方法，对提高内部审核的质量和有效性、获得可靠的审核结论具有重要意义。