Amniotic fluid macrophages from normal and malformed fetuses

Amniotic fluid cells from normal and abnormal fetuses (neural tube defects and abdominal wall lesions) were examined uncultured and after short-term culture for macrophages. Morphology, adherence, phagocytosis, presence of Fc receptors and non-specific esterase were studied. The existence of macrophages in normal and abnormal fluids was confirmed, although the percentage and the absolute numbers varied greatly from specimen to specimen. The most marked increases in total macrophages were in cases of anencephaly. The significance of these macrophages and their value in prenatal diagnosis are discussed.     

Best management practices for airport deicing stormwater

With the advent of new regulations concerning aircraft deicing and management of spent aircraft deicing fluids (ADFs), many airports now face the dual challenges of simultaneously maintaining public safety and protecting the environment. This paper provides a theoretical assessment of the potential environmental impact of stormwater runoff and offers detailed current information on alternative deicing fluid application methods and materials, collection and treatment practices.     

易燃易爆工艺管线焊接缺陷安全评定——上海石化总厂工艺管线的安全评定及其缺陷的返修技术

本文以断裂力学为基础,以“合乎使用”为原则并依据流变应力理论,通过有效地解决无损检测,应力分析、缺陷分类及验收准则等方面所遇到的若干技术问题,对管道焊接缺陷进行了安全评定,正确地区分了严重缺陷和非严重缺陷,从而对评定管道焊接缺陷的严重性提出了一种既安全可靠又经济合理的工程处理法。这一方法已被成功地用于上海石化总厂,对其部分在役易燃易爆工艺管线进行了安全评定并解决了超标焊接缺陷的修复问题。     

油气开采钻井固体废物处理与利用研究现状

对比分析了我国部分地区油气开采钻井固体废物的污染特征,对普通钻井固体废物和含油钻井固体废物的无害化处理与资源化利用技术分别进行梳理和分析,主要包括固化处理技术、生物处理技术、不落地处理技术、资源化利用技术、萃取技术、热解析技术和组合处理技术等。结合当前存在的主要问题针对性地提出了4条对策建议:加强源头控制,减少钻井固体废物产生量;对钻井固体废物进行分质分级区别处理和利用;开发高效、低成本、低能耗的钻井固体废物处理技术,发展联合处理工艺;制定相关政策和标准,加强油气田污染治理的事中事后监管。     

“比例原则”视野下我国环境执法按日连续处罚制度的完善

"按日连续处罚"制度已经在环境执法中显示了巨大的威慑力,但"按照原处罚数额按日连续处罚"的计罚模式不符合行政法中的"比例原则"。在违法行为"先轻后重"或者"先重后轻"的情形下,都可能造成"过罚不当"的问题。对于初始违法情节类似,但复查时违法情节大相径庭的不同违法者,会出现"不同情节相同处罚"的不公平情形。在现有制度框架下,对于"先重后轻"的违法行为,可以考虑在违法者的改正行为已经取得显著成效的情形下不予按日连续处罚,同时依据《环境行政处罚办法》的规定,将该已经显著减轻的违法排污行为视为新的违法行为进行处罚。对于"先轻后重"的违法行为,可以在进行按日连续处罚时,视具体违法情节动用限产停产、查封扣押或者行政拘留等处罚措施。理想状态下,应当摒弃"按照原处罚数额"按日计罚的规定,改为数据值式的按日计罚,即规定"……拒不改正的,处每日××万元以上××万元以下的罚款",以更好地实现"过罚相当"。为了避免持续性违法行为对环境造成更大的损害,按日计罚的最长期限不宜超过三十日。违法者超过三十日仍然不改正违法行为的,应当及时采取责令限产停产、查封扣押或责令关闭等措施。     

A regulatory view on science and predictive models

A lot of scientific knowledge is required to carry out and enforce environmental regulations. The paper deals with the relationship between law and science from a legal perspective. First, some difficulties in using science to carry out environmental regulations are outlined. After this, some legal concepts which try to cope with the problems are presented. Aspects discussed are the precautionary principle, the legal concept of 'state of the art', general standard setting, the flexibility of the regulations, and procedural regulations for the standard-setting process. Finally, the new challenge for science that derives from the legal demand of an integrated approach to environmental protection is addressed.     

湖泊水环境预测的原理与方法

论述了湖泊水环境预测常用方法,主要有输入输出模型、扩散模型、富营养化水质模型和多元回归模型等,属于因果关系的短期和瞬时预测,并且将灰色动态模型和回归分析模型耦合能预测湖泊水环境今后几年甚至几十年的变化,将提高预测效率;提出了湖泊水环境的基本程序;最后指出水资源研究的随机分析、模糊分析和灰色系统的耦合与ＧＩＳ、ＲＳ和ＧＰＳ的应用是今后湖泊水环境预测的发展趋势。     

NUMERICAL AND ANALYTICAL SOLUTIONS OF DISPERSION IN A FINITE,ADSORBING POROUS MEDIUM1

ABSTRACT Numerical and analytical solutions are developed for the distribution of a contaminant within an adsorbing porous medium in a unidirectional flow field subject to a step function for input concentration. The medium is considered to be homogeneous, isotropic, and areally finite. As a by-product, solutions are also obtained for the case of a non-absorbing porous medium. An example that demonstrates the applicability of the solutions is presented.     

Evaluation of Generic Types of Drilling Fluid Using a Risk-Based Analytic Hierarchy Process

The composition of drilling muds is based on a mixture of clays and additives in a base fluid. There are three generic categories of base fluid - water, oil, and synthetic. Water-based fluids (WBFs) are relatively environmentally benign, but drilling performance is better with oil-based fluids (OBFs). The oil and gas industry developed synthetic-based fluids (SBFs), such as vegetable esters, olefins, ethers, and others, which provide drilling performance comparable to OBFs, but with lower environmental and occupational health effects. The primary objective of this paper is to present a methodology to guide decision-making in the selection and evaluation of three generic types of drilling fluids using a risk-based analytic hierarchy process (AHP). In this paper a comparison of drilling fluids is made considering various activities involved in the life cycle of drilling fluids.This paper evaluates OBFs, WBFs, and SBFs based on four major impacts—operations, resources, economics, and liabilities. Four major activities—drilling, discharging offshore, loading and transporting, and disposing onshore—cause the operational impacts. Each activity involves risks related to occupational injuries (safety), general public health, environmental impact, and energy use. A multicriteria analysis strategy was used for the selection and evaluation of drilling fluids using a risk-based AHP. A four-level hierarchical structure is developed to determine the final relative scores, and the SBFs are found to be the best option.     

FIELD MEASUREMENT OF FLOW VELOCITIES,SUSPENDED SOLIDS CONCENTRATIONS,AND TEMPERATURES IN LAKE OKEECHOBEE1

ABSTRACT: This paper presents a field investigation of collecting hydrodynamic and sediment data in Lake Okeechobee with analyses examining mechanisms affecting sediment resuspension in the lake. Lake Okeechobee is a large subtropical lake located in south central Florida. Three‐dimensional flow velocities, suspended solids concentrations (SSC), and temperatures at four locations were measured from January 18 to March 5, 2000. Analyses of these data indicate that wind is the dominant factor in driving flow velocities and therefore transporting suspended solids. Wind direction also affects the SSC, especially in the north central and west littoral areas of the lake. The surface and bottom velocity components frequently flow in opposite directions, forming a stratification of the water column and preventing suspended solids from settling out. This retention of SSC in the water column may have a strong impact on the water quality of Lake Okeechobee. This study provides valuable storm event data and mechanism analyses, which will improve our understanding of the transport of suspended solids, thermal exchanges, and flow patterns within Lake Okeechobee.