中国地下水污染模拟预测标准体系研究现状

地下水污染模拟预测在地下水污染防治的不同阶段工作中重要性日益凸显,为保证模型应用的有效性和准确性,制定标准化的地下水污染模拟预测流程十分必要。在对国内外的地下水污染模拟预测标准体系进行详细介绍的基础上,指出了目前中国地下水模拟预测标准体系构建存在的问题,结合中国相关标准目前的应用现状,提出加快构建地下水污染模拟预测标准体系、增强地下水污染模拟预测标准的约束性、提高地下水污染模拟预测标准的精细化程度等对策和建议,旨在为今后地下水污染模拟预测标准体系研究提供理论依据。     

哈尔滨市地下水脆弱性研究

为正确地判断哈尔滨市地下水水质现状及变化趋势,对研究区地下水脆弱性进行研究。根据研究区水文地质背景条件,选取地下水水位埋深、含水层介质、地形坡度、上覆地层介质、单井涌水量5个参数作为评价因子,利用DRASTIC模型对哈尔滨市地下水脆弱性进行评价,并结合MapGIS实现了地下水环境脆弱性分区。结果表明,地下水脆弱性指数为77~123。其中,松花江及阿什河河漫滩是全市地下水脆弱性最高的区域(指数为108~123),地下水极易受污染;一级阶地区、江北水产养殖场及研究区东北部属于中等脆弱区(指数为93~108);中南部岗阜状高平原区属于低脆弱性地区(指数为77~93),受污染风险较小。研究结果能客观地反映区域内的地下水防护性能,有效地为规划部门及地下水资源管理部门提供指导。     

基于时序蒙特卡罗方法的某铬盐场污染地下水泄漏风险

突发性污染地下水泄漏对周围水环境的影响具有重要研究意义。借鉴时序蒙特卡罗(SMC)方法来模拟污染源运行状态,并结合相应的河流水质模型,对污染地下水泄漏后造成的河流水质超标风险概率进行研究;利用健康风险评价模型,对污染物泄漏时水环境造成的人体健康风险进行评价。以某铬盐场为例验证该方法的稳定性和实用性。结果表明,该场地受污染的地下水对人体健康产生的危害程度为中级,其超标风险概率随模拟时间的增加而趋于稳定。     

涕灭威对地下水污染敏感区的预测与区划试点

本文根据涕灭威在室内模拟试验与田间试验的结果，详细剖析了影响涕灭威农药在土壤中残留和移动的各种因子，建立了涕灭威农药对地下水污染的敏感性模型，并就涕灭威农药在江苏使用后对地下水可能造成污染的情况进行了预测与区划试点，结果与用美国环保局提供的ＰＲＺＭ模型计算结果和田间实测结果基本一致，本模型可用于预测涕灭威农药在其它地区使用后对地下水可能造成污染的情况。     

某电厂堆灰场附近浅层地下水中Cr^6＋的成因及治理措施

分析了焦作某电厂堆灰场附近浅层地下水中Cr^6 的形成原因。根据该区水文地质背景，提出在地下污染水羽的下游建可渗透反应墙的漏斗--通道系统，用对Cr^6 有很高去除效率的风化煤作为反应材料，使污染水羽流经此系统时有效去除地下水中的Cr^6 ，达到净化的目的。     

某电厂堆灰场附近浅层地下水中Cr6+的成因及治理措施

分析了焦作某电厂堆灰场附近浅层地下水中Cr6+ 的形成原因。根据该区水文地质背景 ,提出在地下污染水羽的下游建可渗透反应墙的漏斗 -通道系统 ,用对Cr6+ 有很高去除效率的风化煤作为反应材料 ,使污染水羽流经此系统时有效去除地下水中的Cr6+ ,达到净化的目的     

某电厂堆灰场附近浅层地下水中Cr6+的成因及治理措施

分析了焦作某电厂堆灰场附近浅层地下水中Cr6+的形成原因.根据该区水文地质背景,提出在地下污染水羽的下游建可渗透反应墙的漏斗-通道系统,用对Cr6+有很高去除效率的风化煤作为反应材料,使污染水羽流经此系统时有效去除地下水中的Cr6+,达到净化的目的.     

鹤壁矿区煤矸石淋滤实验研究

对鹤壁煤矿区第10矿煤矸石进行连续淋溶试验,模拟煤矸石矿井填充后对地下水环境的影响.测定pH值、电导率、F^-、总硬度、Zn、Mn、Cr^6＋、Cd、Cu和Pb等项目,实验结果表明,煤矸石淋出液中F^-和Cr^6＋超标,Mn接近标准,pH值偏高,对地下水环境存在一定影响.其他各元素含量甚微,多未检出.     

基于随机-模糊耦合的填埋场地下水污染风险评价方法

为分析参数不确定性对填埋场渗漏风险评估结果的影响,构建了填埋场地下水污染风险评价的物理过程模型,在此基础上,分别采用模糊理论和概率理论刻画模糊不确定性参数和随机不确定性参数,同时采用基于随机理论的Monte Carlo方法模拟模糊不确定参数,最终构建了基于模糊随机耦合的填埋场地下水污染风险评价方法。采用该模型对东北某一般工业固废填埋场进行案例研究,结果表明,实测浓度在模型模拟的的浓度区间(10%~90%分位值浓度)之内。说明本模型构建的模糊-随机耦合的地下水污染风险评价模型能较准确地预测地下水中污染物实际浓度,可以用于填埋场地下水污染风险评价.风险评估结果表明,该填埋场地下水的潜在污染物为As和Mn,其中As为主要健康风险物质,其非致癌风险值超过风险可接受水平的概率为22%,致癌风险超过10-4的概率为33%,超过10-5的概率为86%,应该采取措施控制含As填埋废物中As的溶出,降低其环境风险;Mn的非致癌风险值小于风险可接受水平的概率为100%,无风险。     

化工区地下水污染预测研究方法探讨

作者在查明该区水文地质条件的基础上,提出了化工区水质预测的两种数学模型,一是有限单元法数值离散模型,二是统计模型,并以前者为主要方法,后者作为宏观验证成果的依据对化工区地下水污染进行预测研究。预测结果可靠。     

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.