碱熔法消解-原子荧光法测定土壤中的锡

利用碱熔法消解土样、氢化物发生-原子荧光法测定土壤中的锡。选择最佳的仪器条件,经过碱熔法消解后,在体积分数为5%的盐酸介质中,锡荧光强度与其质量浓度在0～200μg/L成线性关系。方法的相对标准偏差为2.2～7.2%,实际样品加标回收率为90%～95%。此方法操作简便,灵敏度高,检出限低,适用于土壤中微量锡的测定。     

液态锂铅合金残渣中微量氚的回收

氚提取的系统设计中,如何严格限制氚损失和减小其辐射风险是非常重要的问题.利用同位素交换法对模拟液态锂铅合金残渣中的微量氚进行回收.研究结果表明,同位素交换法对液态锂铅合金残渣中的氚回收是有效的;交换载带气的最佳组成为He 0.1% D2.载带气相同时,交换温度和交换次数对渣中氚的回收率有显著影响.温度越高、交换次数越多,氚回收率越高;823 K时,经过6次交换后的氚回收率接近80%.此外,依据气体与液态金属接触的动力学数学模型,推导出了锂铅合金滞留氚量释放的数学近似表达式.     

Framework and Tools for Agricultural Landscape Assessment Relating to Water Quality Protection

While many scientific studies show the influence of agricultural landscape patterns on water cycle and water quality, only a few of these have proposed scientifically based and operational methods to improve water management. Territ’eau is a framework developed to adapt agricultural landscapes to water quality protection, using components such as farmers’ fields, seminatural areas, and human infrastructures, which can act as sources, sinks, or buffers on water quality. This framework allows us to delimit active areas contributing to water quality, defined by the following three characteristics: (i) the dominant hydrological processes and their flow pathways, (ii) the characteristics of each considered pollutant, and (iii) the main landscape features. These areas are delineated by analyzing the flow connectivity from the stream to the croplands, by assessing the buffer functions of seminatural areas according to their flow pathways. Hence, this framework allows us to identify functional seminatural areas in terms of water quality and assess their limits and functions; it helps in proposing different approaches for changing agricultural landscape, acting on agricultural practices or systems, and/or conserving or rebuilding seminatural areas in controversial landscapes. Finally, it allows us to objectivize the functions of the landscape components, for adapting these components to new environmental constraints.     

环境监测数据处理与分析

环境监测是保护环境的重要手段。随着科技发展,监测数据的处理与分析也有了很大的进步,为人类的生活提供了有力的保障。本文从数据获取出发,从多个角度对环境监测数据处理进行分析和研究,同时探讨新型方法在监测数据领域的应用。     

The effects of driver factors and sign design features on the comprehensibility of traffic signs

PROBLEM: This paper addresses the effects of driver factors and sign design features on the comprehensibility of traffic signs. METHODS: A survey was designed to capture subjects' personal particulars, ratings on sign features, and comprehension scores, and then administered to 109 Hong Kong full driving license holders. RESULTS: Years with driving license and education level were significant predictors of sign comprehensibility. Contrary to expectation, the driver factors of age group, years of active driving, hours of driving, last time driving, driving frequency, and non-local driving experience had no effect on comprehension performance. Sign familiarity was correlated with comprehension score for licensed drivers, whereas sign concreteness, simplicity, and meaningfulness were not. IMPACT ON INDUSTRY: The results of this study provide useful guidelines for designing more user-friendly traffic signs in the future. It identified particular driver groups who lacked good understanding of traffic signs, and this information may assist the relevant organizations to better allocate traffic training resources, and better target future studies of traffic sign comprehension.     

美姑河牛牛坝水电站库区泥石流基本特征

金沙江支流美姑河牛牛坝水电站库区泥石流沟分布面积广、发生频率高。调查结果表明库区现有不同类型泥石流沟31条,其中属于高度危险的泥石流沟4条,中度危险的泥石流沟15条。本文对流域面积较大、活动性较强的12条泥石流的容重、设计流速、流量、冲出量等重要工程参数进行了计算,并对水库蓄水后的泥石流沟状况与发展趋势作了进一步分析,研究表明在水库施工期泥石流灾害对工程建设有较严重的影响,特别是靠近库首的泥石流对工程的安全构成威胁。水库蓄水后,库区泥石流活动程度有所降低,不会明显影响水电站正常运行。     

航空遥感影像上震害解译的结构模型与几何特征的获取

首先给出了基于航空遥感影像的震害分类方案及各种震害在遥感图像上的主要特征，提出了一种震害解译的结构模型。然后讨论了震害的几何测度指标，并研究了震害几何特征的获取，最后对遥感影像震害解译的前景进行了展望。     

Development of QSARs to investigate the bacterial toxicity and biotransformation potential of aromatic heterocylic compounds

A series of aromatic heterocyclic and hydrocarbon compounds were tested for toxicity and biotransformation potential against two contrasting lux-marked whole-cell microbial biosensors. Toxicity was determined by inhibition of light output of a Pseudomonas fluorescens construct that expresses lux constitutively. Biotransformation was tested by increase in light output of P. fluorescens HK44 (pUTK21), which expresses lux when in the presence of a metabolic intermediate (salicylate). The data were then modelled against physical/chemical properties of the compounds tested to see if quantitative structure–activity relationships (QSARs) could be derived. Toxicity was found to be accurately predicted by log K_ow (R²=0.95, Q²=0.88), with the basic (pyridine-ring containing) heterocycles modelled separately. The biotransformation data were best modelled using lowest unoccupied molecular orbital (LUMO) energies (R²=0.90, Q²=0.87).     

云南小江流域的泥石流灾害

云南东北部的小江流域是我国泥石流灾害严重地区。本文就其形成原因、运动特征、灾害简况和防治实例作了阐述,并结合生物措施与工程措施的情况,概括出“稳”、“拦”、“排”的治理对策。     

斜剖面图的设计及在PM2.5中期潜势预报中的应用

本文将强降水潜势预报的“配料法”原理引入到环境预报中,选取ECMWF数值预报产品中的700hPa相对湿度、1000hPa风向风速和850hPa温度作为气象要素“配料”,沿占比最多的冷空气输送路径穿过华北重污染区和上海,设计制作了未来10d气象要素“配料”时空斜剖面图,并具体定义了业务中常见的典型污染过程（冷空气输送、干静稳和湿静稳累积）和清洁过程（冷空气清洁、湿沉降清洁）共5种图形的识别特征.该斜剖面图由于融合了单站时序图和单时次空间面图的优点,无需一张张翻阅天气形势图,显著缩短了看图分析时间;斜剖面图还建立了气象要素图形特征、污染气象条件和PM_2.5污染潜势三者的对应关系,通过图形特征可以快速掌握区域内天气形势演变情况,识别出上述典型污染和清洁过程,最终得出PM_2.5中期污染潜势,便于在业务中应用和推广.一次典型污染个例应用显示,斜剖面图和污染实况的图形型态特征非常相似,斜剖面图中静稳累积和冷空气输送过程图形特征辨识度高,区域和单站提前5d的预报结论和实况较为一致;进一步评估显示,2018年冬季期间预报时效5d以内的TS评分维持在0.32~0.50区间,未来10d的预报准确率维持在74.4%~86.7%区间.