引水治污工程水质管理模型的应用研究

研究了绍兴市引水治污工程的水质管理模型,提出了设计引水流量、水质模拟、引水流量的时间调度、控制最大允许排污量等计算方法,并提出用水环境容量增益系数、COD去除率、引水冲污率和引水自净率指标来反映引水治污工程的处理效果.     

基于SWAT模型的流域面源污染模拟影响分析

针对流域面源污染模型往往忽略或简化河道内污染物变化过程的缺陷,探讨了河道水质模型对流域面源污染模拟的影响.以太湖流域浙西区的西苕溪流域为研究对象,选取具有一定物理机制的分布式面源污染模型SWAT模型,分别以激活和不激活其嵌套的河道水质模型QUAL2E,即SWAT模型与QUAL2E模型紧密耦合和松散耦合两种情况进行模拟,并比较了对TN及TP的模拟效果.结果表明,丰水期与平水期的模拟结果并没有显著差别;但在枯水期,由于水量较小,河道内污染物变化过程对模拟结果影响较大.同时引入QUAL2K模型,分析认为改进河道水质模型对提高SWAT模型模拟精度有一定的效果.     

生态修复综合技术在杭州虾龙圩河的应用

杭州虾龙圩河由于多年污染,河道水质严重黑臭,自净能力遭到破坏。本研究通过综合利用底泥污染物削减、生物接触氧化水质净化、造流曝气及水生生态系统修复等技术对虾龙圩河进行治理。结果显示,此项综合技术对城市河流污水具有良好的污染物去除性能,COD、NH3-N和TP的去除率分别可达到73．3％、80．1％和81．7％。通过1年的运行与养护,虾龙圩河治理段的水质、生态环境等有了明显改善,没有发生过水华及黑臭现象,河道水体具备了较强的自净能力。     

基于MIKE11的江南平原河网动态水环境容量分析

传统水环境容量以90%保证率下的设计枯水流量作为计算条件,存在水文计算条件单一、计算结果固定等局限性,不能很好地表征水流方向不定、产汇流过程复杂、污染负荷分散的江南平原河网的水环境容量。以宜兴市官林镇水系为研究对象,基于MIKE11水质模型计算河网控制单元水环境容量,以探究江南平原河网水环境容量的动态特性。结果表明：MIKE11模型法下官林控制单元COD、氨氮和总磷月均水环境容量为-152.80、0.92和-1.69 t;桐梓控制单元COD、氨氮和总磷月均水环境容量为220.23、4.49和1.45 t;皇新控制单元COD、氨氮和总磷月均水环境容量为15.42、0.90和0.14 t,呈现出明显动态特征。代表河道水环境容量与流量流速等水文要素有密切关系,市镇级等水质达标河道水环境容量与流速呈正相关,村级等未达标河道水环境容量与流速呈负相关。本研究可为平原河网水环境保护与管理提供重要参考和新思路。     

城市内河综合水质对再生水补水的响应

为解析再生水补水对城市内河水质的影响,以合肥市塘西河为例,采用一维水动力水质模型,结合模糊模式识别方法,研究再生水补水位置、水质和补水量对塘西河水质的影响。模拟结果表明:再生水补水改变了河流水动力特征、污染物负荷及其扩散降解过程,影响河流水质空间分布,且对补给点附近的河流水质影响最为显著;通过模糊模式识别分析发现,补给点越靠近上游对河流水质的改善作用越大,提高补水水质或增大补水水量均可进一步改善河流水质。     

万家寨引黄北干线桑干河道输水水质模拟与控制

主要对采用河道输水方案的山西万家寨引黄北干线桑干河道水质进行模拟与控制研究,依据各水体特性建立河流水质数值模型和水库数值模型,运用系统分解方法将整个研究河道分解为若干个河段,并采用情景分析方法生成3个水质模拟情景,分析模拟结果表明,在山阴取水口和怀仁取水口水质达地表水Ⅲ类标准条件下,册田水库的入水水质不达标。应用反演思想生成2个水质控制情景和3个子情景,在水库出水口水质达标的情况下,分析确定沿河各排污口的污染物排放控制量,给出了保证册田水库水质安全的控制方法。     

伏牛溪水污染治理效果的数值模拟研究

为评估河流治污措施对河道水质改善的效果,用MIKE11模型对伏牛溪河道主要污染物氨氮和CODMn进行了数值模拟。结果表明:河道沿程点源全部截污后,可降低43%的氨氮和65%的CODMn,水质基本达到Ⅴ类水标准;补充20 000 m3/d污水厂尾水(仅深度处理其中6 000 m3/d),河道氨氮浓度将升高12%、CODMn浓度可降低17%,水质不能满足Ⅴ类水标准;补充20 000 m3/d全部深度处理的污水厂尾水,可以降低39%的氨氮和42%的CODMn,水质基本可达到Ⅴ类水标准;采取组合措施后,氨氮可降低12%~37%,CODMn可降低7%~30%。组合措施优于单一措施。     

疏浚对巢湖双桥河水环境容量的影响

双桥河是巢湖受污染较为严重的入湖河流之一,其入湖口距巢湖市自来水厂取水口仅500 m,同时也是巢湖市的主要行洪河道,为了改善水质状况并提高河道行洪能力,于2010年3—5月对双桥河进行了疏浚。本文作者于2009年12月—2010年10月对双桥河监测断面及排污口进行了监测,在分析双桥河水质及现有污染源的基础上,选择CODMn、TP、NH3-N和TN作为水质敏感参数,对疏浚前后双桥河的不同河段污染物质的水环境容量进行了模拟计算,并调查了水生植被覆盖度及沉积物氮磷含量的变化。结果表明,疏浚后整个河道水生植被的覆盖度由40%降低到5%左右,各污染物的降解系数都有较大程度的降低,同时疏浚后短期内CODMn和TP的环境容量均有一定程度的降低,而NH3-N和TN的环境容量变化较小。分析认为,这一方面是由于疏浚后河道内水生植物覆盖度的降低导致水体的自净能力降低,另一方面是由于疏浚过程中的扰动引起大量沉积物的再悬浮及污染物的释放。所以在减少外来污染的前提下,对重富营养化水体底泥进行疏浚并开展水生植被恢复工程应是控制富营养化的有效途径。     

杭州西湖总磷模型及其治理应用(Ⅱ)

在杭州西湖总磷模型及其治理应用(Ⅰ)的研究基础上,再用平面二维水动力方程、对流扩散方程(其中考虑了底泥沉降及底泥释放同时发生的水与底泥双层介质的交换)数值解,对一个进出水口,引水量2000万t／a8个点浓度的平面分布进行了验证,并研究了多个进水、出水口的布局和引水增加后对西湖各水域水质改善程度。又用最新水质资料作了预测验证。     

淮河流域水生态环境现状评价与分析

为了全面评价淮河闸坝与污染对淮河水生态的影响,必须首先对水生态现状有一个全局的认识。从淮河流域全局出发,通过对淮河典型河段的水生态和水环境进行现场调查与室内分析,对流域内水生态环境现状进行了综合评价。采用生物学指数与水生物指示环境结合的方法评价水体污染程度、生态系统稳定性与河流/水库的健康程度。评价结果表明：(1)颍河中下游地区与沭河中下游地区水生态系统脆弱,河流多处于病态;(2)涡河付桥闸、东孙营闸到蒙城闸段水生态系统不稳定,河流不健康,但下游河段水生态有自恢复迹象;(3)洪汝河河流多处于亚健康状态,水生态环境自修复能力较强;(4)淮干水生态环境质量的突变点在临淮岗,上游较好;(5)西部、南部山区水库水生态环境质量最好;(6)整个流域水生态质量西高东低,南高北低;优劣顺序为：西部、南部山区＞洪汝河水系＞涡河中下游地区＞颍河、沭河中下游地区。建议枯水期加大淮干以南及上游山区水库的下泻流量,保持河道畅通和一定流速,提高水体自净能力,同时控制颍河、涡河上游污染物的排放,联合调度水量与水质,淮河水生态得以修复。     

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.