安全信息认知通用模型构建及其启示

为了揭示复杂系统内安全信息传播的机理与故障模式和发展新的安全模型,以安全信息认知过程为主线,以安全信息失真或不对称为问题,构建了1个包含7个关键事件、6个时间状态、5级信息失真和4级信息传播的安全信息认知通用理论模型,阐述了模型的内涵、特点、用途分类和故障诊断分析途径,并由模型推导出1组安全科学基础理论新概念,同时也建立了1种新的安全信息系统分析与控制的方法论。结果表明,该模型对事故致因机理分析、行为安全管理、系统安全设计和事故防控等的具有重要的理论和实际意义。     

基于改进输出系数模型的云南宝象河流域非点源污染负荷估算

本文引入降雨、地形因子(α、β)对经典的输出系数模型(ECM)进行改进,基于1999~2010年云南宝象河流域气象、水文、社会经济等数据,利用改进的输出系数模型(IECM)对该地区(位于滇池的东北部,绝大部分在官渡区内,西北部少部分在盘龙区内)的非点源污染负荷进行估算.结果显示,2008年宝象河流域非点源氮、磷污染的所占比例(分别为74.2%和68.0%)要显著高于点源氮、磷污染的所占比例(分别为25.8%和32.0%).氮污染中,不同非点源的贡献率依次为土地利用类型>大气沉降>农村生活>畜禽养殖;磷污染中,不同非点源污染的贡献率为土地利用类型>农村生活>大气沉降>畜禽养殖.宝象河流域的非点源氮污染比例要高于整个滇池流域,非点源磷污染比例与滇池流域较为接近.与实际观测值比较,IECM对TN、TP负荷的估算值的平均相对偏差分别为15%和-6%,ECM对TN、TP负荷的估算值的平均相对偏差分别为54%和17%.这表明改进的输出系数模型(IECM)提高了结果的准确性,可以为滇池流域的污染(尤其是非点源污染)负荷估算提供参考方法.     

Applying chemical sedimentation process in drinking water treatment plant to address the emergent arsenic spills in water sources

Arsenic (As) spills occurred more frequently and sometimes polluted water sources in recent years in China. It is as urgent need to develop emergency treatment technologies to address the arsenic threat for large-scale water treatment plants. In response, we developed a chemical sedimentation technology to remove arsenic contaminants for water treatment plants. Bench-scale experiments were conducted to investigate the efficiency of arsenic removal and the influencing factors of the chemical sedimentation treatment process. The influencing factors included the choice and dosage of coagulants, the valence of arsenic and pH value of solution. The As(V) contaminants can be almost completely removed by ferric or alum coagulants. The As(III) contaminants are more recalcitrant to chemical sedimentation, 75% for ferric coagulant and 40% for alum coagulant. The quantitative results of arsenic removal load by different ferric or alum coagulants were presented to help determine the parameters for arsenic treatment technology. The dominant mechanism for arsenic removal is static combination, or adsorption of negative arsenic species onto positive ferric hydroxide or alum hydroxide flocs. The efficiency of this treatment technology has also been demonstrated by a real production test in one water treatment plant with arsenic-rich source water and one emergency response. This technology was verified to be quick to set-up, easy to operate and highly efficient even for high concentration of arsenic.     

The influence of chlorinated aromatics' structure on their adsorption characteristics on activated carbon to tackle chemical spills in drinking water source

This study focused on evaluating the efficiency of powdered activated carbon (PAC) adsorption process and tackling chlorobenzenes and chlorophenols spill in drinking water source. The adsorption kinetics and PAC’s capacities for five chlorobenzenes and three chlorophenols at drinking water contamination levels were studied in order to determine the influence of different functional groups on the adsorption behavior. The results showed that PAC adsorption could be used as an effective emergency drinking water treatment process to remove these compounds. The adsorption kinetics took 30 min to achieve nearly equilibrium and could be described by both pseudo first-order and pseudo second-order models. A mathematic relationship was developed between the pseudo first-order adsorption rate constant, k₁, and the solutes’ properties including lgK_ow, polarizability and molecular weight. The Freundlich isotherm equation could well describe the adsorption equilibrium behaviors of chlorinated aromatics with r² from 0.920 to 0.999. The H-bond donor/acceptor group, hydrophobicity, solubility and molecular volume were identified as important solute properties that affect the PAC adsorption capacity. These results could assist water professionals in removing chlorinated aromatics during emergency drinking water treatment.     

基于资源价值折耗的石油资源账户建立与分析——以黄河三角洲石油开发为例

在国际上通行的环境经济综合核算体系(SEEA)的基础上,以黄河三角洲石油资源开发为研究案例,根据黄河三角洲2003-2008年石油开发利用等数据,经过计算和统计依次建立了石油资源的实物型账户、价值型账户和综合账户。计算和统计结果表明:2003-2008年,黄河三角洲石油资源因开采而造成的价值折耗分别为154.0×10⁸、111.3×10⁸、121.6×10⁸、104.9×10⁸、106.0×10⁸、83.0×10⁸元,考虑了资源价值折耗的石油行业增加值占工业增加值和地区GDP的比例,以及因价值折耗造成的工业经济和地区GDP损失比例都有减小的趋势,平均分别为59.1%和42.0%,以及14.3%和9.8%。巨大的价值折耗带来了石油资源利用的可持续性下降,但是在当地的整体经济中,黄河三角洲石油开发带来的经济增长的可持续性在一定程度上增强。最后对结果进行了分析和讨论。     

Fluorescence excitation-emission matrix combined with regional integration analysis to characterize the composition and transformation of humic and fulvic acids from landfill at different stabilization stages

Fluorescence excitation-emission matrix spectroscopy (EEMs) combined with fluorescence regional integration (FRI) analysis was used to investigate the composition and transformation of humic acid (HA) and fulvic acid (FA) from landfill. The EEMs of HAs at different landfill ages were characterized by two typical fluorescence chromophores with Ex/Em pairs at Ex = 420-470 nm/Em = 490-530 nm and Ex = 345-375 nm/Em = 450-465 nm. EEMs of FA were featured by other two distinctly different fluorophores with Ex/Em pairs at Ex = 315-335 nm/Em = 420-440 nm and Ex = 255-275 nm/Em = 425-455 nm. The results show that HA extracted from the refuse disposed in the year of 1989 was formed by connecting small-condensed aromatic structures with protein-like chains. Compared with HA extracted from the refuse disposed in the year of 1992, HA extracted from the refuse of 1996 had a higher fluorescence intensity and lower r_(B,A) (the ratio of the fluorescence intensities of peak B and peak A) value. It contained low molar mass components, low aromatic condensation degree, and more easily oxidized substituents. This indicates that the landfill time strongly affects the EEMs characteristics of HA, and that the humification degree of HA increases with the landfill time. A red shift to a longer wavelength region and an increase of fluorescence intensity were observed when the concentration of HA was increased, suggesting that concentration had a great influence on the fluorescence characteristics of HAs. pH (2-12) also had significant effects on the fluorescence intensity, although it exerted no effect on the peak position of fluorescence of HA and FA. The results of FRI show that increasing concentration lead to more interactions among various structure components and that small molecular weight units tend to aggregate or be masked into more complicated and larger structures. The pH influence on the fluorescence intensity of HA seems mainly through molecular configuration, while the fluorescence intensity change with pH may be due to various substituents of FA.     

基于归一化差值植被指数的极端干旱气象对西南地区生态系统影响遥感分析

以年际同期归一化差值植被指数(Normalized Difference Vegetation Index,NDVI)作为评价指标,分析极端干旱气象对西南地区生态系统影响的时空分布特征,提出旱灾可能造成的生态影响及应采取的管理和科研措施. 结果表明:2009年8月—2010年3月,西南地区的生态系统受极端干旱天气影响显著,威胁程度呈上升趋势;贵州、广西和云南三省(自治区)受干旱影响的生态系统面积先后超过各省份生态系统总面积的80%,生态系统强度变差区集中在云南的中东部、贵州西南部和广西西北部等地区;农田生态系统受损严重,农作物大面积枯死或绝收;大量水库、池塘干涸,河流水位明显下降,部分河流断流,危及水生生物生存;自然植被影响明显,植被生长明显受到抑制,干热河谷地带和岩溶地形区域植被大面积退化,威胁当地生物多样性.      

基于生境适宜度的成都震后大熊猫生境评价

通过分析大熊猫生境适宜度指标,评价“5\512汶川大地震”对成都地震灾区大熊猫生境的影响并提出恢复措施. 结合大熊猫生境的物理环境、生物环境和压力三方面因素建立评价指标体系,运用层次分析法确定评价指标权重,并利用GIS空间叠加分析对大熊猫生境适宜度进行综合评价,将结果分为最适宜、适宜、较不适宜和不适宜4种类型. 对比地震前后大熊猫生境适宜度变化显示:震后大熊猫生境的景观破碎化程度明显增加,生态廊道受到不同程度的破坏,大熊猫适宜生境面积减少,其中,彭州市龙门山镇变化最大,适宜生境减少2 729.5 hm2;其次为都江堰市虹口乡、龙池镇与彭州市小鱼洞镇,其适宜生境分别减少1 760.4,303.5和241.1 hm2. 针对研究结果,提出恢复重建的优先次序以及需要生态修复的重点区域,给出优先采取工程和生物措施,并辅助以自然恢复的修复手段.      

水培技术作为人工湿地预处理工艺可行性研究

以城市污水处理厂初沉池出水为原水,对以美人蕉为栽培植物的水培生态净化槽作为复合人工湿地预处理工艺的可行性进行了现场试验研究.结果表明,水培槽对COD、SS的最大平均去除率分别达到了64.8%和88.7%,有效地削减了人工湿地的COD负荷和降低了湿地介质孔隙堵塞的风险.在0.10,0.30,0.60m三种不同槽深条件下,槽深越浅,出水中的DO浓度越高,越有利于水中污染物的去除,运行水深是决定水培槽对污水净化效率的重要参数,另外,与水培槽相组合的复合潜流人工湿地对水中的污染物去除效率较高且效果稳定,出水COD和SS可达到国家《城镇污水处理厂污染物排放标准》中的一级B标准,氨氮和总磷可达到二级标准.     

Electrophysiological responses of Dendroctonus armandi (Coleoptera: Curculionidae: Scolytinae) to volatiles of Chinese white pine as well as to pure enantiomers and racemates of some monoterpenes

To better understand the attractiveness of host tree, Chinese white pines (Pinus armandi Fr.) to Chinese white pine beetle (Dendroctonus armandi Tsai and Li), the antennal responses of D. armandi to the host volatile, as well as the pure enantiomers and racemates of some monoterpenes, were examined using an electroantennogram (EAG). EAG responses of male and female D. armandi to blended volatiles extracted from the host and some synthetic terpenes (α-phellandrene, (−)-β-pinene, (+)-α-pinene, (−)-α-pinene, (−)-camphene, β-myrcene, (S)-(−)-limonene, (+)-camphene and (R)-(+)-limonene) showed significant variation due to different compound concentrations and sex of the beetles. EAG responses to extracted blended volatiles were significantly greater in females than in males, but the EAG response was not always proportional to the volatile concentration. At lower concentrations, females responded strongly to α-phellandrene and males to (−)-β-pinene, while at higher concentrations, females responded most strongly to α-phellandrene and males to (+)-α-pinene. Females were significantly responsive to (−)-α-pinene, α-phellandrene and (−)-camphene, while males were more responsive to (S)-(−)-limonene, (+)-α-pinene and (R)-(+)-limonene. The EAG responses of the female D. armandi to the volatile oil were significantly higher than that of the males, and the infested pine volatiles could evoke higher EAG response. Most of the test compounds elicited similar responses, which suggested that several of the compounds may be used in combination by D. armandi in habitat and/or host community location at the Qinling forest ecosystem.