一组含氟取代苯化合物土壤吸附系数的QSPR分析

为了研究含氟取代苯化合物的环境行为,测定１４个含氟取代苯化合物的土壤有机碳吸附系数Ｋｏｃ的值,运用正辛醇／水分配系数Ｋｏｗ及分子连接性指数和量子化学参数进行了定量结构－性质相关分析,得到２个回归方程。回归方程表明Ｋｏｗ与分子连接性指数结合可较好地预测含氟取代苯化合物的Ｋｏｃ而量子化学参数的引入证明了极性作用地土壤吸际过程的影响。     

分子拓扑学参数及其在定量结构——活性相关(QSAR)研究中的应用

本文阐述了定量结构—活性相关研究中常用的几个拓扑学参数的定义及其计算方法,对相关数据进行了归纳整理,并通过实例阐述了拓扑学参数在ＱＳＡＲ研究中的重要作用。     

稀土元素La对油菜某些生理指标的影响及其临界浓度

通过水培试验 ,研究了稀土元素La对油菜生物量和叶绿素含量、硝酸还原酶活性、根系活力、POD活性等一系列生理指标的影响。结果表明 :喷施或根施 0 0 3～ 3mg/kg的La3+对油菜的生长起了一定的促进作用 ,表现为生物量、叶绿素含量、硝酸还原酶活性和根系活力增加 ;而高于 3 0mg/kg浓度的La3+对油菜的生长产生了抑制作用 ,油菜生物量、叶绿素含量、硝酸还原酶活性和根系活力降低 ,POD活性增高。La对油菜的临界浓度为 3 0mg/kg。     

动物园中褐马鸡生理生化指标的研究

褐马鸡（Ｃｒｏｓｏｐｔｉｌｏｎｍａｎｔｃｈｕｒｉｃｕｎ）是我国一类保护动物,世界濒危物种．建立自然保护区和动物园饲养是保护濒危动物的有效措施．因此,了解在不同生态环境中褐马鸡生理生化指标的变化对它的饲养、繁殖和疾病防治及其保护都具有一定的实际意义．迄...     

水资源社会可再生性及其基本理论

水资源具有自然和社会可再生性。本文从水资源可再生的特性出发，提出水资源社会可再生性的涵义及其在水资源可再生系统中的地位，系统地分析了水资源社会可再生实现过程、其衡量指标及影响因素。基于我国水资源短缺形势，本文认为水资源社会再生利用是城市水资源有效利用的重要途径，是解决或缓解我国水资源短缺的重要手段，并给出提高水资源可再生性的建议。     

Effect of Climatic Changes on Radial Increment and Age Structure Formation in High-Mountain Larch Forests of the Kuznetsk Ala Tau

The relationship between growth indices and renewal rates of the Siberian larch (Larix sibiricaLedeb.) stands that have grown at the timberline in the Kuznetsk Ala Tau mountains during the past 350 years was analyzed. The age generations of larch were formed in the 1640s, 1660s, 1680s, 1700s, 1720s, 1740s, 1760s–1770s, 1800s–1810s, 1850s, 1870s–1880s, 1900s, 1920s, and 1930s–1940s. It was shown that the formation of these age generations coincided with 10- to 30-year periods of increased growth of larch and improved temperature conditions in summer.     

Availability estimation of a multi-state wind farm in fuzzy environment

Wind is one of the fastest growing renewable energy resources in the electric power system. Availability of wind energy is volatile in nature due to the stochastic behavior of wind speed and non-linear variation of the wind power curve of wind turbine generator. Because of this impression and uncertainty, the availability estimation of wind power has become a challenging issue. In this paper, Markov Fuzzy Reward technique has been proposed for finding out the reliability of wind farm by assessing the availability of wind power. According to this technique, availability of the wind power has been estimated considering wind farm and demand both as a multi-state system. In addition to the availability, different reliability indices such as the number of absolute failures, mean time to deficiency, and probability of failures of a wind farm have been assessed in a time horizon, which can provide useful information for the power system planner at wind farm installing stage. A comparison of this study reveals the efficacy of the proposed Markov Fuzzy Reward approach over the conventional Markov Reward approach.     

A Framework for Analyzing Longitudinal and Temporal Variation in River Flow and Developing Flow-Ecology Relationships1

Larned, Scott T., David B. Arscott, Jochen Schmidt, and Jan C. Diettrich, 2010. A Framework for Analyzing Longitudinal and Temporal Variation in River Flow and Developing Flow-Ecology Relationships. Journal of the American Water Resources Association (JAWRA) 46(3):541-553. DOI: 10.1111/j.1752-1688.2010.00433.x Abstract: We propose a framework for analyzing longitudinal flow variation and exploring its ecological consequences in four steps: (1) generating longitudinally continuous flow estimates; (2) computing indices that describe site-specific and longitudinal flow variation, including intermittence; (3) quantifying and visualizing longitudinal dynamics; (4) developing quantitative relationships between hydrological indices and ecological variables (flow-ecology relationships). We give examples of each step, using data from a New Zealand river and an empirical longitudinal flow model, ELFMOD. ELFMOD uses spot-gauging data and flow or proxy variable time series to estimate flow magnitude and state (flowing or dry) at user-defined intervals along river sections. Analyses of flow-ecology relationships for the New Zealand river indicated that fish and benthic and hyporheic invertebrate communities responded strongly to variation in mean annual flow permanence, flow duration, dry duration, drying frequency, inter-flood duration, and distances to flowing reaches. To put longitudinal flow variation into a broader context and guide future research, we propose a conceptual model that combines elements of two contrasting perspectives: rivers as longitudinal continua, and rivers as patch mosaics. In this conceptual model, hydrologically complex rivers are composed of linear sequences of nested hydrological gradients, which are bordered by hydrogeomorphic discontinuities, and which collectively generate hydrological dynamics at river-section scales.     

广东农业旱灾的时间分布规律及重灾年份预测

广东是华南农业旱灾较严重的省份，几乎年年都有发生，造成了巨大的经济损失。过去55a间，农业旱灾波动性加重发展，大致以10a为周期，轻重灾害期交替出现。在重灾期内，受灾率和成灾率都很高。广东农业旱灾的受灾率异常指数和成灾率异常指数变化较大，据此建立了农业旱灾灰色灾变预测模型。计算结果表明，今后20a将出现3个重灾年份，即2010-2011年，2015-2017年和2022—2024年期间，后两个年份极有可能发生特大旱灾。     

I2SI: A comprehensive quantitative tool for inherent safety and cost evaluation

This paper presents details of an integrated inherent safety index (I2SI). The conceptual framework of this index was presented at the 37th Annual Loss Prevention Symposium of the AIChE (2003) and published in Process Safety Progress (volume 23(2), 136–148, 2004). In addition to the framework, the current paper discusses additional features of the index such as the cost model and system design model, which were not presented or discussed earlier. I2SI is called an integrated index because the procedure considers the life cycle of the process with economic evaluation and hazard potential identification for each option. I2SI is comprised of sub-indices which account for hazard potential, inherent safety potential, and add-on control requirements. In addition to evaluating these respective characteristics, there are also indices that measure the economic potential of the option. To demonstrate the applicability and efficacy of I2SI, an application of the index to three acrylic acid production options is also discussed in the paper.