污水污泥间壁热干燥实验研究

研究了污泥间壁热干燥的工艺过程,分析了其工艺参数、冷凝水水质和产生的污染气体,探讨了有机物水解机理.结果表明,污泥含水率与停留时间呈负指数函数相关.收集到的干燥冷凝水属高浓度有机废水,其总有机碳（TOC）、挥发性有机酸（VFA）和氨氮（NH₃-N）浓度均很高,pH值保持在9～9.5.干燥冷凝水中挥发性有机酸和氨氮来源于2部分：低温110 ～130℃时,主要发生蛋白质的水解,生成有机酸和氨氮;高温140～150℃时,主要发生脂肪类的水解,生成有机酸.干燥温度低于150 ℃时,污泥间壁热干燥过程无污染气体产生.     

基于GIS的松花江干流暴雨洪涝灾害风险评估

以黑龙江省内的松花江干流流域作为研究区,从现代灾害风险理论出发,综合运用GIS空间分析和灾害风险评估数学方法,对松花江干流流域的暴雨洪涝灾害风险进行了定量评价.研究利用遥感数据和社会经济数据,在空间分析基础上,通过对暴雨洪涝灾害的危险性、承灾体的暴露性、脆弱性以及区域防灾减灾能力的分析,确定影响各个县市暴雨洪涝灾害风险的具体方面.并将因子集成为洪涝灾害风险指数(FDRI),在此基础之上绘制出松花江干流流域的洪涝灾害风险区划图,结果表明松花江干流洪涝灾害风险以哈尔滨和佳木斯两市最大,上游洪涝灾害风险大于下游.     

酸化油页岩灰吸附Ni(Ⅱ)的研究

采用质量分数为50%的HNO3制备酸化油页岩灰吸附剂,研究吸附时间、吸附温度、Ni(Ⅱ)初始浓度、溶液pH值、吸附剂投加量和吸附剂粒径对酸化油页岩灰吸附性能的影响.结果表明,一定范围内,酸化油页岩灰吸附剂的吸附量(Qe)随吸附温度、Ni(Ⅱ)初始浓度、溶液pH值、吸附剂投加量的增加而增加,随吸附剂粒径的增加而减小.吸附温度对吸附刺的最大吸附量Q有明显影响.当Ni(Ⅱ)初始质量浓度为100 mg/L,溶液pH值为6.0,吸附剂粒径为53～75μm,吸附剂投加量为16.0 g/L,吸附搅拌速度为400 r/min时,25℃、30℃、35℃下酸化油页岩灰的最大吸附量Q分别为17.0 mg/g、33.2mg/g、42.9mg/g,且吸附主要以离子交换的化学吸附方式为主.酸化油页岩灰吸附剂对Ni(Ⅱ)的吸附符合Languir等温吸附方程,温度为25℃、30℃、35℃,溶液pH值为6.0,油页岩灰吸附剂投加量为16.0 g/L,油页岩灰吸附剂粒径为53～75μm条件下,酸化油页岩灰对Ni(Ⅱ)的最大吸附量Q分别为17.0mg/g、33.2 mg/g、42.9 mg/g.研究表明,油页岩灰经过酸化改性后可作为吸附荆处理含Ni(Ⅱ)废水,具有较好的市场应用前景.     

基于可拓学石化装置失效后果严重度评估方法研究

石化企业中,石化装置的安全运行对保证企业的安全生产起到关键作用,其一旦失效发生事故,将导致巨大的人员伤亡及财产损失。因此,开展石化装置失效后果严重性的评价研究,对保证石化企业的安全生产具有重要意义。本文根据物元可拓性理论,结合石化装置失效后果的严重性情况,运用可拓评判方法建立石化装置失效后果严重度的综合评判模型,给出了评价步骤,最终确定设备失效后果的严重程度。研究结果表明,该方法可应用于多层次的工程风险评价问题,从而为石化工程项目风险管理提供了一种有效的分析方法。     

Spatial distribution of aerosol pollution based on MODIS data over Beijing, China

With the help of regression analysis,the relationships were detected between aerosol's contribution to apparent reflectance(ACR) derived from Moderate Resolution Imaging Spectroradiometer(MODIS)on board Terra and hourly PM_(10)mass concentration measured at 30 ground-based locations in Beijing for the August of 2003 and 2004.It was shown that there was a good correlation between the ACR and PM_(10)(linear correlation coefficient,R=0.56).On the basis of this relationship,spatial distribution and possible sources of PM_(10)derived from MODIS were analyzed and two frequently heavily-polluted regions were found,namely downtown of the city and the district near Xishan Mountain.These two regions coincidently are also urban heat island centers.The foundings of this paper will be greatly useful for environmental monitoring and urban planning for Beijing,especially for the 2008 Olympic game to be held in Beijing.     

以植被生物完整性评价梁子湖湖滨湿地生态系统健康

湖滨湿地植被是湖滨带生态系统的主要特征,以湖滨湿地植被为对象可评价湖滨带生态系统健康状况。通过对梁子湖湖滨湿地植被的详细调查,共鉴定出植物182种,隶属于52科128属,其中湿生植物147种,水生植物35种。水生植物中有20种挺水植物,6种浮叶植物和9种沉水植物。采用植被生物完整性(VIBI)方法评价梁子湖湖滨湿地生态系统健康,对21个备选指标进行筛选分析,建立了以挺水植物物种数、多年生植物物种数、外来物种百分比、香农多样性指数、植物区系质量指数FQAI、耐受性物种百分比、敏感性物种百分比为核心指标的评价体系,三分法对指标进行赋值,将梁子湖湖滨湿地划分为健康、良好、一般和较差4个等级。评价结果表明,梁子湖湖滨湿地22个调查位点中,处于健康状态的有3个位点,良好6个,共占总位点数的41%,一般和较差分别为7个和6个,共占59%。总体上看,东梁子湖和牛山湖湖滨湿地位点健康状况较好,而西梁子湖湖滨湿地差异性较大,山坡湖南部湖湾和前江大湖北部位点健康状况良好,张桥湖湖滨湿地健康状况一般,评价较差的6个位点集中在宁港湖周围和前江大湖南部沿岸。底质和人类活动如水位调控、围网养殖、放牧等是影响梁子湖湖滨湿地植被生物完整性的主要原因。     

生态足迹研究现状及基于净初级生产力的计算方法初探

生态足迹是一种有效的再生资源更新能力的定量测度方法,其主要用于评估给定年,给定技术条件下生物圈的再生能力能否满足人类消费需求。本研究对国内外生态足迹模型的理论假设、生态足迹、生物承载力、生态盈余、生态赤字进行了简要介绍;在对国际组织发布的生态足迹报告以及生态足迹文献发表情况进行统计的基础上,回顾了国内外的生态足迹计算方法——基于净初级生产力的计算方法,并与现有的基于全球农业生态区的计算方法进行了比较,探讨了两种方法的优缺点;最后对生态足迹今后的研究重点提出了一些看法和展望。     

降水量时间序列变化的小波特征

利用小波变换对降水量时间序列的多时间尺度变化及突变特征进行了探讨。小波变换不仅能将降水量时间序列的频率特征在时间域上展现出来，清晰地给出各种时间尺度的强弱和分布情况以及早涝变化趋势和突变点，而且还能分析出其主要周期。以新安江流域黄山地区主汛期(5—7月)和年降水量为例，计算表明，其年际及年代际时间尺度在时域中分布不均匀，具有明显的局部化特征；同时分析出主汛期降水具有8年、19年左右的周期，年降水存在6年、19年左右的周期；研究还表明，主汛期降水与年降水的时间尺度变化比较接近。     

Plasticity in metamorphic traits of <Emphasis Type="Italic">Rana kukunoris</Emphasis> tadpoles: The interactive effects of food level and rearing temperature

Larval amphibians are particularly likely to encounter variation in rearing temperature and resource availability due to variation in aquatic breeding habitats. In this study, plasticity in growth rates, larval mass, larval period, and size at metamorphosis were examined in Rana kukunoris Nikolskii, 1918 under different combinations of temperature and food level. Larval period and larval body mass was sensitive to food level, and varied with temperature. Tadpoles metamorphosed at an older age at low temperature than those reared at warm temperature. Food level was a significant affect on larval period at low temperature, but not at warm temperature. Mass was heavier for tadpoles reared at low temperatures than those reared at warm temperatures. The effect of food level depended on temperature, because larvae reared at low temperature that were offered a high food level achieved a larger size than larvae offered a low food level, but this did not occur at warm temperature. Therefore, we suggest that high food availability at low temperature prolonged developmental periods, thus larvae are larger as metamorphs than those reared at warm temperatures.     

Using air quality modeling to study source–receptor relationships between nitrogen oxides emissions and ozone exposures over the United States

Human exposure to ambient ozone (O₃) has been linked to a variety of adverse health effects. The ozone level at a location is contributed by local production, regional transport, and background ozone. This study combines detailed emission inventory, air quality modeling, and census data to investigate the source–receptor relationships between nitrogen oxides (NO_x) emissions and population exposure to ambient O₃ in 48 states over the continental United States. By removing NO_x emissions from each state one at a time, we calculate the change in O₃ exposures by examining the difference between the base and the sensitivity simulations. Based on the 49 simulations, we construct state-level and census region-level source–receptor matrices describing the relationships among these states/regions. We find that, for 43 receptor states, cumulative NO_x emissions from upwind states contribute more to O₃ exposures than the state's own emissions. In-state emissions are responsible for less than 15% of O₃ exposures in 90% of U.S. states. A state's NO_x emissions can influence 2 to 40 downwind states by at least a 0.1 ppbv change in population-averaged O₃ exposure. The results suggest that the U.S. generally needs a regional strategy to effectively reduce O₃ exposures. But the current regional emission control program in the U.S. is a cap-and-trade program that assumes the marginal damage of every ton of NO_x is equal. In this study, the average O₃ exposures caused by one ton of NO_x emissions ranges from ? 2.0 to 2.3 ppm-people-hours depending on the state. The actual damage caused by one ton of NO_x emissions varies considerably over space.