一种台风灾情综合评估模型及应用

对台风灾情评估提出了一种基于台风灾害案例历史案例分析、综合模糊数学和灰色关联分析的综合评估模型;利用模糊隶属函数将台风灾情原始数据无量纲化,再设定一极重灾为参考序列。根据台风各评估指标与参考序列的距离,计算出关联系数;将关联系数加权平均和定义为灾度,根据灾度值评定台风的灾级。并以广东省台风灾情为例,验证了此模型。     

污水湿地处理工程水力停留时间的测定

利用ＵＡＰ对一个湿地处理工程的实际水力停留时间进行了测定,进而对相关问题进行了探讨。     

Perchlorate removal using granular activated carbon supported iron compounds: Synthesis, characterization and reactivity

Synthesis and use of the iron compounds supported on granular activated carbon (ICs/GAC) have shown significant environmental implications for perchlorate (ClO 4 ) removal. ICs/GAC was synthesized via hydrolyzing FeSO 4 ·7H 2 O on GAC, reduced by NaBH 4 solution in polyethylene glycol 6000 and ethanol solution, dried in vacuum condition and exposed to air. Synthesized ICs/GAC was characterized using transmission electron micrograph (TEM), Brunauer-Emmett-Teller, X-ray photoelectron spectroscopy (XPS). ICs/GAC was determined to be containing a large amount of FeOHSO 4 , Fe 2 O 3 and a small amount of zero-valent iron (ZVI) nanoparticles according to TEM and XPS measurements. Batch static kinetic tests showed that 97% of ClO 4 was removed within 10 hr at 90°C and 86% of ClO 4 was removed within 12 hr at 25°C, at ICs/GAC dosage of 20 g/L. The experimental results also showed that FeOHSO 4 and Fe 2 O 3 nanoparticles have the function of perchlorate adsorption and play important roles in ClO 4 removal. The activation energy (E a ) was determined to be 9.56 kJ/mol.     

环境—经济系统能值（Emergy）评价：介绍Odum的能值理论

介绍了美国著名生态学家Ｈ．Ｔ．Ｏｄｕｍ创立的能值理论，通过具体实例来分析环境－ 能值特征，评价环境征税的经济价值，阐明自然环境与人类经济相互协调发 的重要性，为人们正确评价环境和从事科研提供新思路。     

基于ASM2D模拟的双流态UNITANK改进工艺的设计与实验分析

针对传统UNITANK污泥浓度不稳定、低负荷释磷不充分以及池体容积比例不合理等不足,提出了改进工艺:双流态UNITANK;利用ASM2D模型对改进工艺进行模拟分析,并通过实验对其进行了验证。结果表明,基于ASM2D的模拟是有效的,双流态UNITANK有效克服了传统UNITANK存在的不足。     

钢桁架连梁耗能性能试验研究及损伤分析

根据两组钢桁架连梁在反复荷载作用下的试验结果,对该新型连梁的破坏形态、滞回性能、耗能能力和累积损伤模型等进行了分析,探讨了钢桁架连梁累积损伤的发展过程和损伤发育规律,通过损伤模型计算的破损结果与试件实际破坏特征对比,讨论了跨高比对连梁损伤发展的影响.结果表明:有交叉腹杆的连梁,跨高比越大,其耗能能力、承载力以及变形均较大,但其损伤发展相对较快.     

100 MW锅炉NaOH颗粒生成的数值模拟

煤粉燃烧过程中矿物质的气化、成核、凝结等过程是炉膛中亚微米颗粒形成的主要途径。本文运用CFD软件针对某100 MW锅炉内NaOH颗粒形成进行了数值研究,计算得到了炉内的温度分布、氧浓度分布和亚微米颗粒数量浓度和质量浓度分布。结果显示,亚微米颗粒的生成数量与温度具有强烈的相关性,温度较高的区域亚微米颗粒数量浓度较大,温度较低的区域则较小;而在炉膛的高温区内,NaOH颗粒的质量浓度并不是最高,而是最低,同时随着炉膛高度的增加,NaOH颗粒的质量浓度逐渐增加。计算结果为今后数值研究燃煤过程中亚微米颗粒的形成与演化奠定基础,为研究温度等燃烧条件对亚微米颗粒形成的影响、抑制其排放等方面提供了一种有效研究手段。     

2-Chlorophenol induced hydroxyl radical production in mitochondria in Carassius auratus and oxidative stress--an electron paramagnetic resonance study

In our previous study, electron paramagnetic resonance (EPR) evidence of reactive oxygen species (ROS) production in Carassius auratus following 2-chlorophenol (2-CP) administration was provided. To further investigate the potential pathway of ROS production, liver mitochondria of C. auratus was isolated and incubated with 2-CP for 30 min. An EPR analysis indicated ROS was produced, and intensities of ROS increased with increasing concentrations of 2-CP. The ROS was then assigned OH by comparing with Fenton reaction. Either catalase or superoxide dismutase, extinguished OH completely in the mitochondria mixture. These facts suggested that O2(.-) and H2O2 contributed to the formation of OH in mitochondria in C. auratus stressed by 2-CP. Combining previous references and our own data, it is reasonable to suggest that 2-CP is first oxidized by H2O2 present in vivo to form phenoxyl radical under the catalytic action of cellular peroxidase (1); phenoxyl radical oxidizes mitochondria NADH to NAD in the presence of NADH (2); NAD reacts with oxygen in vivo to produce O2(.-) (3); O2(.-) is spontaneously dismutated by SOD to form H2O2 and O2, which creates a renewable supply of H2O2 as the initiators of the chain reactions until NADH is consumed (4); simultaneously with reaction (4), O2(.-) reacts with H2O2 to form OH radical via the Haber-Weiss reaction (5). A strong negative correlation (r=-0.9278, p<0.01) between glutathione (GSH) pool and OH production was observed after fish were i.p. injected with 2-CP (250 mg kg(-1)), indicating the depletion of GSH caused by OH.     

Enhanced effect of HAH on citric acid-chelated Fe(II)-catalyzed percarbonate for trichloroethene degradation

This work demonstrates the impact of hydroxylamine hydrochloride (HAH) addition on enhancing the degradation of trichloroethene (TCE) by the citric acid (CA)-chelated Fe(II)-catalyzed percarbonate (SPC) system. The results of a series of batch-reactor experiments show that TCE removal with HAH addition was increased from approximately 57 to 79% for a CA concentration of 0.1 mM and from 89 to 99.6% for a 0.5 mM concentration. Free-radical probe tests elucidated the existence of hydroxyl radical (HO^•) and superoxide anion radical (O₂ ^•-) in both CA/Fe(II)/SPC and HAH/CA/Fe(II)/SPC systems. However, higher removal rates of radical probe compounds were observed in the HAH/CA/Fe(II)/SPC system, indicating that HAH addition enhanced the generation of both free radicals. In addition, increased contribution of O₂ ^•- in the HAH/CA/Fe(II)/SPC system compared to the CA/Fe(II)/SPC system was verified by free-radical scavengers tests. Complete TCE dechlorination was confirmed based on the total mass balance of the released Cl⁻ species. Lower concentrations of formic acid were produced in the later stages of the reaction for the HAH/CA/Fe(II)/SPC system, suggesting that HAH addition favors complete TCE mineralization. Studies of the impact of selected groundwater matrix constituents indicate that TCE removal in the HAH/CA/Fe(II)/SPC system is slightly affected by initial solution pH, with higher removal rates under acidic and near neutral conditions. Although HCO₃ ⁻ was observed to have an adverse impact on TCE removal for the HAH/CA/Fe(II)/SPC system, the addition of HAH reduced its inhibitory effect compared to the CA/Fe(II)/SPC system. Finally, TCE removal in actual groundwater was much significant with the addition of HAH to the CA/Fe(II)/SPC system. The study results indicate that HAH amendment has potential to enhance effective remediation of TCE-contaminated groundwater.

     

The reductive degradation of 1,1,1-trichloroethane by Fe(0) in a soil slurry system

Most studies on the treatment of chlorinated contaminants by Fe(0) focus on aqueous system tests. However, few is known about the effectiveness of these tests for degrading chlorinated contaminants such as 1,1,1-trichloroethane (TCA) in soil. In this work, the reductive degradation performance of 1,1,1-TCA by Fe(0) was thoroughly investigated in a soil slurry system. The effects of various factors including acid-washed iron, the initial 1,1,1-TCA concentration, Fe(0) dosage, slurry pH, and common constituents in groundwater and soil such as Cl^?, HCO₃ ^?, SO₄ ^2?, and NO₃ ^? anions and humic acid (HA) were evaluated. The experimental results showed that 1,1,1-TCA could be effectively degraded in 12 h for an initial Fe(0) dosage of 10 g L^?1 and a soil/water mass ratio of 1:5. The soil slurry experiments showed two-stage degradation kinetics: a slow reaction in the first stage and a fast reductive degradation of 1,1,1-TCA in the second stage. The reductive degradation of 1,1,1-TCA was expedited as the mass concentration of Fe(0) increased. In addition, high pHs adversely affected the degradation of 1,1,1-TCA over a pH range of 5.4–8.0 and the reductive degradation efficiency decreased with increasing slurry pH. The initial 1,1,1-TCA concentration and the presence of Cl^? and SO₄ ^2? anions had negligible effects. HCO₃ ^? anions had a accelerative effect on 1,1,1-TCA removal, and both NO₃ ^? and HA had inhibitory effects. A Cl^? mass balance showed that the amount of Cl^? ions released into the soil slurry system during the 1,1,1-TCA degradation increased with increasing reaction time, suggesting that the main degradation mechanism of 1,1,1-TCA by Fe(0) in a soil slurry system was reductive dechlorination with 1,1-DCA as the main intermediate. In conclusion, this study provides a theoretical basis for the practical application of the remediation of contaminated sites containing chlorinated solvent.