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311.
以《固体废物痕量金属元素的测定电感耦合等离子体发射光谱法》编制说明(征求意见稿)中精密度数据为例,方法标准编制单位在处理方法验证数据时,应按照《GB/T 6379.2—2004》离群值剔除方法处理异常数据,避免重复性限r和再现性限R计算错误。  相似文献   
312.
It can be difficult for assessors and decision-makers to compare different options for a project, and thus come to a reasoned and objective decision concerning the impacts and its sustainability at the local level. Therefore, using integrated assessment becomes crucially important for evaluating proposed different options. In this paper, we apply the Rapid Integrated Sustainability Assessment Method (RISAM) to evaluate the proposed unmitigated options for a municipal waste disposal site in Tehran, Iran. The results obtained showed that all of the alternative unmitigated options to the current method of open dumping were indicated as being consistent with very weak sustainability. The RISAM method demonstrated offers potential considerable benefits with respect to improved efficiency, reduced need for resources, and improved consistency and transparency in evaluation and reporting.  相似文献   
313.
使用格子Boltzmann方法对含尘气体通过布袋滤料纤维的流动进行了数值模拟,采用拉格朗日方法跟踪了颗粒相中每个粒子的位置和速度并进行单向耦合计算。分析了气流通过纤维捕集体过程中的压降的变化规律,结果与达西渗透定律吻合。与此同时,对粒径小于1μm的气溶胶粒子在布袋纤维捕集体上的沉积规律展开了讨论。结果表明,粒径小于0.01μm的粒子的捕集主要受粒子的布朗随机扩散效应的控制;粒径大于0.1μm的粒子则主要依靠纤维滤料的拦截作用而沉积在捕集体表面;而粒径在0.01~0.1μm范围的粒子则具有较低的捕集效率。模拟结果为研究袋式除尘的过滤机理提供了依据。  相似文献   
314.
运用转移—份额分析法(SSM)对2000-2009年黑龙江省入境旅游外国客源市场结构演变进行了分析.结果表明:①2000-2005年黑龙江省竞争力和增长率均较小,2005-2009年竞争力有所增强,但结构优势有所下降.②全省入境旅游客源市场结构在不断变化,将13个主要客源国分为兴旺市场、崛起市场、成熟市场和停滞市场,并提出相应的市场营销建议.  相似文献   
315.
古建筑的消防安全工作作为古建筑保护工作内容的重要组成部分,需要深入开展的消防科学的研究工作.目前在我国,缺少关于古建筑防火安全方面的规范,通常使用的处方式规范一般不适用于古建筑.性能化方法能够提供更加灵活和符合实际的解决方案.并且这可能是唯一可行的使古建筑达到可接受风险水平的方法.以布达拉宫东大殿为研究对象,探讨了性能化防火分析方法在古建筑防火保护中的应用.以对古建筑进行早期探测报警为目标进行了消防设施设置.应用FDS软件进行了模拟研究,根据模拟结果进行分析,得到了一些有益的结论并应用于消防设施设置.通过对探测器响应时间分析,探测器的设置合理,能够在第一时间报警,并且实现了消防安全设计的科学化、合理化和成本效益的最优化.  相似文献   
316.
A method for the analysis of 10 perfluorinated compounds (PFCs) in whole fish homogenate is presented and applied to 60 fish samples collected from the Ohio, Missouri, and upper Mississippi Rivers in 2005. Method accuracy ranged between 86 and 125% with limits of quantitation between 0.2 and 10 ng/g wet weight. Intra- and inter-batch precision was generally ±20%. Perfluorooctane sulfonate (PFOS) was the predominant compound identified in these samples, contributing over 80% of total PFC composition in the fish from these rivers, with median PFOS concentrations of 24.4, 31.8, and 53.9 ng/g wet wt in the Missouri, Ohio, and Mississippi Rivers, respectively. Median PFOS levels were significantly (p = 0.01) elevated in piscivorous fish (88.0 ng/g) when compared with non-piscivorous fish (15.9 ng/g). The 10 samples with PFOS concentrations above 200 ng/g were broadly scattered across all three rivers, providing evidence of the widespread presence of this compound in these US waterways.  相似文献   
317.
开发区工业用水量预测方法研究   总被引:4,自引:0,他引:4  
本文阐述了开发区环境影响评价过程中开发区工业用水量预测的重要性及存在的问题,采用综合指标法和行业用水系数法分别计算了某开发区的现状用水量和规划期间的用水量,行业用水系数法的预测结果与现状吻合较好。对比分析了两种方法的依据、原理及优缺点,行业用水系数法的依据数据更新快,方法适应性好,且逐渐得到认可,推荐采用行业用水系数法进行开发区工业用水量的预测。  相似文献   
318.
This paper presents the results of an intensive monitoring activity of the particulate, fall-out and soil of selected living areas in Italy with the aim to detect the asbestos concentration in air and subsequent risk of exposure for the population in ambient living environments, and to assess the nature of the other mineral phases composing the particulate matrix. Some areas were sorted out because of the presence of asbestos containing materials on site whereas others were used as blank spots in the attempt to detect the background environmental concentration of asbestos in air. Because the concentration of asbestos in ambient environments is presumably very low, and it is well known that conventional low–medium flow sampling systems with filters of small diameter (25 mm) may collect only a very small fraction of particulate over a short period, for the first time here, an intense monitoring activity was conducted with a high flow sampling system. The high flow system requires the use of large cellulose filters with the advantage that, increasing the amount of collected dust, the probability to collect asbestos fibers increases. Both the protocol of monitoring and analysis are novel and prompted by the need to increase the sensitivity towards the small number of expected fibers. With this goal, the collection of fall-out samples (the particulate falling into a collector filled with distilled water during the monitoring shift) and soil samples was also accomplished. The analytical protocol of the matrix particulate included preliminary X-ray powder diffraction (XRPD), optical microscopy and quantitative electron microscopy (SEM and TEM). Correlations with climatic trends and PM10 concentration data were also attempted.The surprising outcome of this work is that, despite the nature of the investigated site, the amount of dispersed asbestos fibers is very low and invariably lower than the theoretical method detection limits of the SEM and TEM techniques for identification and counting of asbestos fibers. The results are compared to the literature data worldwide and an updated model for asbestos fibers dispersion in ambient environments is proposed.  相似文献   
319.
Traditional high resolution mass spectrometry (HRMS) analysis for polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) can be time consuming and expensive. Consequently, alternative methods are of great interest to regulatory agencies and others characterizing contaminated sites. One factor that hinders acceptance of alternative methods is a lack of performance information that assesses the alternative method's impacts on analytical results. The U.S. Environmental Protection Agency's Superfund Innovative Technology Evaluation Monitoring and Measurement Technologies Program (EPA SITE MMT) encourages the development and implementation of innovative and alternative monitoring methods by providing performance information on site characterization technologies. This paper presents a comparison of the results obtained from laboratory-based alternative approaches for screening sediment and soil samples for dioxin toxicity equivalents (TEQ(D/F)) to results obtained using traditional HRMS. The laboratory-based approaches included modifying the traditional HRMS analysis to make it more cost-effective (alternate 1613B), analyzing extracts that had been prepared for HRMS using low resolution mass spectrometry, and determining total organic carbon (TOC) content as an indicator of PCDD/F content. These comparisons demonstrated that TEQ(D/F) values generated using toxicity equivalency factors proposed by the World Health Organization in 1998 applied to alternate 1613B and LRMS analyses have a strong linear correlation to the TEQ(D/F) values derived in the same fashion from traditional HRMS analysis. These results would have placed >90% of the samples within the same concentration intervals using ranges of <0.05, 0.05-0.50, 0.50-5, and >5ng TEQ/g. Natural log transformed data for TOC had significantly weaker correlation to TEQ(D/F), indicating that TOC is not a reliable indicator of TEQ(D/F) concentrations.  相似文献   
320.
This paper examines how three Swedish landscape types (open, forested, and varied) affect driver behaviour. The study was carried out in 2007 under controlled conditions in the VTI Driving Simulator III, Linköping, Sweden. Qualitative (questionnaires) and quantitative (simulator measurement) data were used. Eighteen subjects were selected, nine men and nine women aged 25–65 years, all licensed to drive for at least five years. Two hypotheses were established based on previous research: 1) landscape character (open, forested, or varied) affects driving behaviour (average speed, variation in lateral vehicle position, and steering wheel grasping frequency); and 2) landscape character affects driver perception of the driving situation. The first was tested in the driving simulator and the second via questionnaires concerning the simulator drive. The results indicate that the driver is affected by different landscape types. In the open landscape, subjects drove faster, did not drive as close to the centre of the road, and grasped the steering wheel more often while simultaneously experiencing less stress. Landscape also appears to be relevant to traffic safety, which has implications for choosing new routes when planning new roads and for maintaining existing roads.  相似文献   
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