高浓度苯酚降解菌Candida tropicalis Z-04的鉴定及其对苯酚降解条件的优化

从降解苯酚的好氧颗粒污泥中筛选出一株苯酚降解菌,该菌株最高可耐受2.0 g/L的苯酚.依据形态特征和内源转录间隔区(ITS)的核酸序列分析,将该菌株鉴定为热带假丝酵母菌(Candida tropicalis),并命名为Candida tropicalis Z-04.采用中心复合设计(CCD)法对Candida trop...     

固定化解脂耶氏酵母间歇式处理油脂废水研究

固定化解脂耶氏酵母菌(Yarrowia lipolytica)在气升式反应器中处理色拉油浓度为2 000 mg/L、COD为3 000 mg/L的高COD油脂废水。结果表明,固定化菌对废水的最佳处理时间为6 d,可间歇式处理9批次高COD油脂废水,重复处理废水后,其对油脂的降解均在85%以上,对COD的降解在70%以上,降解后的排出水pH稳定在3.6~3.8。且处理动力学方程属于一级生化方程。结果进一步表明,固定化解脂耶氏酵母菌在气升式反应器中适于处理高COD含油脂的污水。     

响应面法优化酵母菌处理餐饮废水

从餐饮废水集水井壁上的生物膜中筛选出酵母菌菌株,选择废水降解能力相对较高的3株酵母菌对餐饮废水进行处理。以COD去除率为主要指标,在单因素实验的基础上,运用响应面法对pH、TN和TP进行优化,得到酵母菌处理餐饮废水的最优条件。结果表明,酵母菌处理餐饮废水最优的工艺条件为pH=5.55、TN=27.63mg/L、TP=4.40mg/L,COD去除率达到90.3%;当进水COD为2235mg/L、油为660.2mg/L时,COD与油实际去除率分别达到了89.9%和89.8%。     

不同pH条件下酵母菌处理高含油废水的研究

在使用混合酵母菌菌株处理高浓度含油废水中,研究了序批式反应器(SBR)内酵母菌在不同起始pH条件下对废水的处理效果.通过与pH中性或碱性条件比较发现,pH 4～5的条件在酵母菌的发泡抑制、菌体生长以及COD/油去除等方面均显示出更好的效果,pH 5是系统运行的最佳条件.长达100d的SBR连续运行试验表明,系统可以在pH=5条件下长期、稳定运行.     

污泥中嗜酸酵母菌的分离鉴定及其重金属耐受性研究

从污水处理厂的活性污泥中分离纯化出一株嗜酸异养菌,命名为JJU-2,并对其进行了形态观察、生理生化特性测试及26SrDNA的D1/D2区序列分析,鉴定该菌株为假丝酵母菌(Candida palmioleophila)。进一步对JJU-2菌株的生长特性和重金属耐受性进行研究。结果表明:该菌株最适生长pH为3~6,且能适应pH3的极端酸性环境,最适生长温度为25℃,最高耐受温度为40℃,当培养至3h,JJU-2菌株进入对数生长期,培养至18h进入稳定期。Cr~(3+)、Ni~(2+)、Pb~(2+)对JJU-2菌株的最低抑菌摩尔浓度分别为20、2.0、40mmol/L。     

混合固定化酵母菌对苯并(α)芘污染土壤的修复

将3株酵母菌进行两两混合及3株混合后,采用物理法和化学法对其进行固定化包埋,用于多环芳烃苯并(α)芘污染土壤的修复.实验结果表明,酵母菌经过混合固定化包埋后,通过降解率及降解动力学分析可以得出,其降解效果明显好于游离菌,这是由于酵母菌经过包埋后,载体内部菌密度有效增加的结果.空白对照虽未接菌种,但污染物也有少量的下降,这是由于载体中含有一定量的活性炭,对污染物具有吸附作用,这种吸附作用随着时间的延长而趋于平缓.由实验结果还可以看出,物理法更适合对酵母菌进行混合固定化包埋,但并非混合酵母菌菌株越多,降解效果越好.菌株IM219-220-phy对苯并(α)芘的降解率最高达40.65%,半衰期为5.66 d.     

固废拆解场污染土壤中多环芳烃降解菌的筛选鉴定与降解特性

以腐植酸(HA)溶液为吸附剂、从受多环芳烃污染的土壤中分离出来的降解菌制成为生物修复剂,以多环芳烃(PAHs)萘、菲、芘、荧蒽、苯并蒽、苯并芘为土壤污染物,对PAHs污染土壤进行修复实验。目的是筛选与分离吸附于HA的PAHs降解菌,研究HA与降解菌的协同效应对PAHs的降解效率的影响。用经过HA吸附的PAHs富集分离培养出1株高效降解菌株,命名为Tzyx3,鉴定其为解脂耶氏酵母菌(Yarrowia lipolytica)。15 d后,土壤中萘、菲、芘、荧蒽、苯并蒽、苯并芘的降解率分别为90.7%、91.0%、74.7%、86.9%、84.7%和74.7%,表明Tzyx3和HA在PAHs污染土壤中存在协作关系,Tzyx3能够直接利用HA对土壤中的多环芳烃进行降解。     

酵母菌处理马铃薯淀粉废水研究

马铃薯淀粉废水属高浓度废水,COD达到30 000 mg/L左右,BOD为15 000 mg/L左右,可生化性较好。针对废水中主要含有淀粉、蛋白质和可溶性纤维等成分,筛选分离出能降解这些有机成分的6种酵母。以废水为培养液分别培养这6种酵母及其混合菌,实验结果表明,各酵母菌株对该废水都有较好的降解效果,混合菌的处理效果要好于单个菌株。在连续流废水培养条件下,混合酵母活性和菌体量也较高,MLSS稳定在12 g/L左右,其COD去除率稳定在77%左右。     

构建酵母融合子净化味精废水及其性能研究

失活的热带假丝酵母(Candida tropicals CBJ302)原生质体与未失活的酿酒酵母(Saccharomyces cerevisiae SEB926)原生质体,在35％聚乙二醇(MW:6000)和0.1MCa~(2+)诱导下融合,形成融合子。经培养鉴定,失活的热带假丝酵母代谢淀粉的糖化酶系统,在融合子中被未失活的酿酒酵母原生质酶系激活。以扫描电子显微镜X—650F放大12000倍摄影,观察到亲株细胞,脱壁过程中的双亲细胞和融合子杂种细胞外部形态的明显区别。SC-F-3融合子在味精生产废水中24小时的SCP生产率最高,分别为亲株的1.4和1.2倍。融合子SC-F-5的24小时去除化学耗氧量(COD_(cr))的水平高达40％,分别为亲株的1.8和2.1倍。结果表明,融合子杂种酵母细胞在COD_(cr) 22500mg/l的味精废水中具有提高生产SCP效率和增强净化废水功能的潜力。     

混合耐冷菌群的优化筛选及应用研究

从冬季时污水处理厂曝气池的活性污泥中分离出高生物活性的耐冷细菌和耐冷酵母菌,以低温生活污水为处理对象,分别测定单株菌及混合耐冷菌群有机污染物降解能力.结果表明,共分离出从属于黄杆菌属、假单胞菌属、芽胞杆菌属等的耐冷细菌6株;从属于毕赤酵母菌属、假丝酵母菌属、红酵母菌属等的耐冷酵母菌4株.耐冷菌在5℃条件下具有相对较短的世代时间:9.04～13.11 h.单株耐冷细菌F和耐冷酵母菌AH在5℃条件下的COD去除率分别为64%和83%.混合耐冷菌群经驯化后可较高地去除低温生活污水中的有机污染物,COD去除率可保持在83%～87%.     

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).     

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。     

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。     

An application of the theory of kinematics of mixing to the study of tropospheric dispersion

The most common technique used for numerical simulations of tracer mixing is that of the numerical solution of the advection–diffusion equation with the unresolved fluxes parameterized using the similarity theory. Despite correct predictions of the overall directions of transport, models based on a numerical solution of the advection–diffusion equation lack sufficient accuracy to correctly reproduce the coupling of mixing with small scale processes which are sensitive to the microstructure of the tracer distribution. The objective of this paper is to revisit the basic formalism employed in numerical models used to investigate atmospheric tracers. The main mathematical method proposed here is the theory of kinematics of mixing which could be applied effectively for simulations of atmospheric transport processes. At the beginning of the paper, we introduce simple mathematical transformations in order to demonstrate how complex topological structures are created by mixing processes. These idealistic flow systems are essential to explain transport properties of much more complex three-dimensional geophysical flows. An example of the application of the kinematics of mixing to the analysis of tracer transport on a planetary scale is presented in the following sections. The complex filamentary structures simulated in the numerical experiment are evaluated using some commonly applied statistical measures in order to compare the results with the data published in the literature. The results of the experiment are also analysed with the help of simple conceptual models of fluid filaments. The microstructure of the tracer distribution introduced in the paper is essential to increase our understanding of atmospheric transport and to develop more realistic parameterizations of small-scale mixing. The presented results could also be used to improve calculations of the coupling between microphysical processes and tracer mixing.     

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     

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.