Clair油田——管理裂缝性油藏水驱开发中的不确定性

Clair油田于2005年2月投产。Clair油田是一个大油藏（〉4O亿桶储罐原始石油地质储量），位于设得兰以西75公里处。它是英国已开发的最大的天然裂缝油藏，并且用水驱开发。该油田的评价期长达28年，反映了该油藏高度复杂、常规地震成像质量相对较差和传导性裂缝的不确定性影响。[第一段]     

防止球罐上下极板温差过大的措施

球罐在进行整体热处理中存在上下极板温差较大的现象,影响球罐热处理效果。本文针对该现象提出了预防措施,可确保球罐热处理的质量。     

黔北地区构造特征与下寒武统页岩气储层裂缝研究

裂缝发育程度是页岩气储层的主控因素之一,而裂缝的形成与构造特征密切相关。在对黔北地区构造特征分析的基础上,对该区下寒武统牛蹄塘组黑色页岩地层的裂缝特征及分布进行了研究。认为黔北地区褶皱、断裂发育复杂,褶皱整体以隔槽式为主,断裂是在多个走向断裂体系相互切割、联合下形成的,各断裂体系的主形成期具有差异性;构造裂缝是下寒武统黑色页岩层段的主要裂缝类型,而且以水平缝与低角度缝所占比例大。裂缝发育区的分布主要受到断裂带的控制,其中以北东向和北北东向断裂体系的控制作用最为显著,裂缝发育区多位于断裂带的末端、拐点处、不同走向断裂带相交处和相同走向的断层夹持带等应力集中部位。其次,在背斜的高陡部位,也有利于裂缝的形成。     

Accumulation of atmospheric and sedimentary PCBs and toxaphene in a Lake Michigan food web

Seston, sediment, settling organic matter, and food web members were collected from Grand Traverse Bay, Lake Michigan, between April 1997 and September 1998 to examine PCB and toxaphene biomagnification. Stable isotopes of nitrogen and carbon were analyzed in samples and used to establish trophic structure of the food web and to determine the importance of atmospheric versus sedimentary sources in delivering PCBs to the food web. Nitrogen isotopes were confounded by multiple variables in this system, particularly seasonal variation, and did not display a simple pattern of enrichment among trophic levels. However, delta13C displayed little seasonal variation and was positively correlated with PCB concentrations among food web members (r2 = 0.69). Plots of delta13C vs PCBs separate food web members into three distinct groupings comprised of invertebrates, primary forage fish, and predatory fish. Stable isotope values of the primary organic sources indicate that the atmosphere, and not the sediment, is the most likely source of PCBs to the food web of Lake Michigan. Additionally, we suggest that seston may be important in delivering PCBs to pelagic food web members and species that receive a majority of their nutrition through pelagic sources. In contrast, settling particles are implicated in delivering PCBs to benthic organisms and Mysis relicta.     

Enhanced airborne polychlorinated biphenyl (PCB) concentrations and chlorination downwind of Lake Ontario

Air samples were collected simultaneously at three sites downwind of Lake Ontario and at a control site near Lake Erie from March to July of 1999. The Lake Erie site (Stockton, NY) had PCB concentrations similar to rural Integrated Atmospheric Deposition Network (IADN) sampling sites across the Great Lakes, exhibited limited seasonal variation, and approximates regional background. Samples taken along Lake Ontario's southeastern shore (Rice Creek and Sterling, NY) had elevated PCB concentrations averaging approximately 1 ng/m3 and were more chlorinated than air collected at IADN sites and at Stockton. Air samples from Potsdam (approximately 75 km inland) had similar concentrations but were less chlorinated. Clausius-Clapeyron plots revealed a strong correlation between PCB fugacity and temperature near Lake Ontario; however, the extent of chlorination of the air samples rules out volatilization from the lake as a major source. It is hypothesized that volatilization from local surfaces, enriched in higher chlorinated congeners by meteorological or geographic factors, drives both the concentration and composition of airborne PCBs along Lake Ontario's southeastern shore.     

Synthesis and structure-activity study of quaternary ammonium functionalized beta-cyclodextrin-carboxymethylcellulose polymers

Carboxymethylcellulose (CMC) and beta-cyclodextrin (beta-CD)-based polymers functionalized with two types of quaternary ammonium compounds (QACs), the alkaquat DMB-451 (N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride) (DMD-451) named polymer DMB-451, and FMB 1210-8 (a blend of 32 w% N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride and 48 w% of didecyldimethylammonium chloride) named polymer FMB 1210-8, were synthethized and characterized by Fourier transform infrared spectroscopy. The antimicrobial activities of these polymers against Eschericia coli were also evaluated at 25 degrees C in wastewater. The results have indicated that the polymer FMB 1210-8 possesses a high-affinity binding with bacterial cells that induces a rapid disinfection process. Moreover, in the same experimental conditions of disinfection (mixture of 1.0 g of polymer and 100 mL of wastewater), the polymer FMB 1210-8 has a higher antimicrobial efficiency (99.90%) than polymer DMB-451 (92.8%). This phenomenon might be associated to a stronger interaction with bacterial cells due to stronger binding affinity for E. coli cells and greater killing efficiency of the C10 alkyl chains QAC of polymer FMB 1210-8 to disrupt the bacterial cell membrane as compared to N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride. Together, these results suggest that the polymer FMB 1210-8 could constitute a good disinfectant against Escherichia coli, which could be advantageously used in wastewater treatments due to the low toxicity of beta-CD and CMC, and moderated toxicity of FMB 1210-8 to human and environment.     

Samplinghelper a web-based tool to assess the reliability of sampling strategies in sewers and receiving waters

Sampling is a key step in the analysis of chemical compounds. It is particularly important in the environmental field, for example for wastewater effluents, wet-weather discharges or streams in which the flows and concentrations vary greatly over time. In contrast to the improvements that have occurred in analytical measurement, developments in the field of sampling are less active. However, sampling errors may exceed by an order of magnitude those related to analytical processes. We proposed an Internet-based application based on a sampling theory to identify and quantify the errors in the process of taking samples. This general theory of sampling, already applied to different areas, helps to answer questions related to the number of samples, their volume, their representativeness, etc. The use of the internet to host this application facilitates use of theoretical tools and raise awareness of the uncertainties related to sampling. An example is presented, which highlights the importance of the sampling step in the quality of analytical results.