甲草胺和丁草胺等除草剂在多介质环境中环境行为综述

本文详细综述了甲草胺和丁草胺的物理化学性质,总结了它们在土壤和水中的迁移,吸附和微生物降解转化,对动植物的毒性和作用机制,酰胺类除草剂在分析检测方面的进展以及在污染的防治与修复方面的一些措施     

膜污染状态下的胞外聚合物、细菌数量及微生物群落结构研究

研究了膜污染状态下膜生物反应器(MBR)中混合液污泥和膜丝表面污泥的胞外聚合物(EPS)含量、细菌数量以及微生物种群结构的情况。结果表明:EPS主要由蛋白质组成,膜丝表面污泥中的EPS含量较高,高达68.3mg/g;MBR污泥中细菌的数量级基本达109个/g,其中膜丝表面污泥细菌数量较高;MBR混合液污泥和膜丝表面污泥微生物群落的Shannon-Weaver指数分别为2.639和2.303,两者微生物群落结构的相似性系数达到0.833,两者的优势菌均为黄色单胞菌,变形杆菌门和拟杆菌门是膜丝表面种类较多的菌群,可能与膜污染有密切的联系。深入分析膜污染形成原因和过程,对膜污染的防治具有重要的意义。     

重金属与土壤微生物的相互作用及污染土壤修复

阐述了微生物与重金属间的相互作用 ,指出土壤重金属污染影响微生物活性、生物量 ,且重金属对微生物具有一定的生态毒性。可通过微生物的氧化 还原作用、生物吸附富集和溶解作用 ,达到修复重金属污染土壤的目的。     

指示水体病原污染的微生物及其检测

受粪便污染的水体可能含有严重威胁人类和动物健康的致病微生物,由于病原微生物在水环境中往往数量较少、检测比较困难,通常采用检测与病原微生物具有密切关系的指示微生物来指示和估计病原污染.指示微生物包括总大肠菌群及其替代微生物,已被广泛应用于水体污染程度检测等方面.总结了各种指示微生物的特性、应用范围以及检测方法等方面的最新研究进展.初步介绍了指示微生物和水环境之间的关系,着重介绍了判断病原微生物污染来源的指示微生物及其最新检测方法.     

Cr(Ⅵ)污染的微生物修复技术及研究进展

Cr(Ⅵ)污染的防治与修复问题一直受到广大学者的高度关注,常规物理、化学修复技术去除Cr(Ⅵ)的经济性较差,易造成二次污染,微生物修复技术可将有毒的Cr(Ⅵ)还原为相对无毒的Cr(Ⅲ),是一种环保高效的修复技术。综述了Cr(Ⅵ)污染的来源及危害,介绍了目前所分离的Cr(Ⅵ)还原菌株及其修复Cr(Ⅵ)的影响因素,概述了国内外微生物修复Cr(Ⅵ)污染的研究进展,旨在为Cr(Ⅵ)微生物修复技术的实践应用提供理论依据。     

重金属与土壤微生物的相互作用及污染土壤修复

阐述了微生物与重金属间的相互作用，指出土壤重金属污染影响微生物活性、生物量，且重金属对微生物具有一定的生态毒性。可通过微生物的氧化-还原作用、生物吸附富集和溶解作用，达到修复重金属污染土壤的目的。     

硫酸盐还原菌的污染与防治方法

硫酸盐还原菌 ( Sulphate-Reducing Bacteria,简称SRB)是一群严格厌氧的异养型微生物 ,其分布遍及全球 ,主要存在于水体的深部和浅部、下水道和油田等处 ,它们与石油、煤炭矿藏有关 ;它们在生态环境中的广泛分布及其特殊的代谢活动对人类环境和国民经济产生明显的影响 ,人们对此越来越重视 ,对 SRB的研究也在不断深入。在环境科学的研究中 ,SRB在水处理 (特别是厌氧处理工艺 )中的应用已有报道[1 ] ,而对 SBR引起的污染与防治办法却鲜见报道。本文拟对此进行介绍。1　对水体的污染与防治1 .1　对水体的污染SRB对水体的污染是由有机…     

砷污染土壤微生物修复机制及其研究进展

土壤砷污染是一个全球性问题。越来越多的研究表明,自然界中的微生物在砷的迁移转化过程中发挥了重要作用。微生物修复是目前研究的热点,也是治理砷污染土壤的主要手段之一。综述了土壤中砷污染现状及其赋存形式,重点分析讨论了砷污染土壤的微生物修复机制以及提高微生物修复效率的方法。土壤砷污染修复是一项复杂的系统工程,单一的修复技术很难实现显著的效果。只有建立在以微生物修复为主的基础上,辅之以物理化学、植物及农业生态等措施,才能大大提高微生物修复效率。总结了近年来国内外微生物修复砷污染土壤技术的研究进展,以期为深入研究微生物代谢砷的机制及其在砷污染治理中的应用提供参考。     

宝应县畜禽养殖业的现状调研及污染防治对策

调查了宝应县畜禽养殖业的发展现状及分布情况,阐述了该县畜禽养殖业的污染防治状况,分析了污染防治中存在的主要问题,并提出了当地畜禽养殖业污染防治的基本思路和治理措施,对贯彻落实防治措施提出了建议。     

基于寡培养可视化的铀污染检测的微生物组合

为了评估监测铀污染对环境影响程度,为环境治理提供参考依据,本研究通过筛选获得对铀胁迫敏感和抗性的2类微生物,用以响应土壤或水体的铀污染,并考察其对铀污染响应灵敏度。实验筛选得到的红色敏感菌与粉色抗性菌经鉴定分别为粘质沙雷氏菌(Serratia marcescens)和玫瑰色考克氏菌(Kocuria rosea),明显的菌落特征实现了微生物检测的可视化与简单化。通过寡培养基的应用,成功地以粘质沙雷氏菌:玫瑰色考克氏菌为1∶2的比例构建了微生物检测体系。经验证,该体系在水体中能够检测出铀的最低浓度约为5 mg·L~(-1),在土壤中能检出的铀浓度高于10 mg·kg~(-1)才有明显效果,表明本微生物组合对于监测水体和土壤铀污染是有效的。该体系为水体和土壤铀污染的微生物监测提供了前期技术基础。同时,寡培养方式的使用为外界因素对微生物的影响的"效果保真培养"提供了一定的参考。     

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).     

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。     

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。     

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     

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.     

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.     

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.