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461.
河流水污染损失补偿模型研究 总被引:4,自引:1,他引:3
我国水污染问题的突出表现之一是省际间、地区间水污染纠纷接连不断, 严重影响经济发展和社会稳定。在流域不同主体之间建立水污染补偿机制,可以把水污染造成的环境外部损失内部化,从而促使污染者在治污成本和经济补偿之间进行权衡,促进水污染治理措施的有效执行和水污染纠纷的解决。在水污染经济损失评估的基础上,以河流为研究对象,采用水环境数学模型的方法描述了污染物排放的空间影响关系,进而把超量排放的环境影响与经济影响联系起来,对模型的基本特征、处理方法和应用范围进行了讨论,并且以太湖流域范围内的京杭运河为例进行实证研究,得到了河流水污染损失补偿的数学模型。 相似文献
462.
试验考察了东阿县污水处理厂一期A2/O工艺厌氧池去除有机污染物效能,当进水ρ(COD)为548.3 mg/L时,厌氧池平均去除率达78.7%。同时探讨了几种常见数学模型模拟厌氧池去除有机物规律情况,根据实际工程监测数据确定有机底物降解动力学常数,得出Grau模型、Stover-kincannon模型和改进的Monod模型较适合模拟厌氧池去除有机物的规律,并对模型进行了检验。 相似文献
463.
TiO2 nanotubes as solid-phase extraction adsorbent for the determination of
polycyclic aromatic hydrocarbons in environmental water samples 总被引:1,自引:0,他引:1
Bochra Bejaoui Kefi Latifa Latrous El Atrache Hafedh Kochkar Abdelhamid Ghorbel 《环境科学学报(英文版)》2011,23(5):860-867
An analytical method based on TiO2 nanotubes solid-phase extraction (SPE) combined with gas chromatography (GC) was
established for the analysis of seven polycyclic aromatic hydrocarbons (PAHs): acenaphtylene, acenaphthene, anthracene, fluorene,
phenanthrene, fluoranthene and pyrene. Factors a ecting the extraction e ciency including the eluent type and its volume, adsorbent
amount, sample volume, sample pH and sample flow rate were optimized. The characteristic data of analytical performance were
determined to investigate the sensitivity and precision of the method. Under the optimized extraction conditions, the method showed
good linearity in the range of 0.01–0.8 g/mL, repeatability of the extraction (RSD were between 6.7% and 13.5%, n = 5) and
satisfactory detection limits (0.017–0.059 ng/mL). The developed method was successfully applied to the analysis of surface water
(tap, river and dam) samples. The recoveries of PAHs spiked in environmental water samples ranged from 90% to 100%. All the results
indicated the potential application of titanate nanotubes as solid-phase extraction adsorbents to pre-treat water samples. 相似文献
464.
Tao Zhang Qiucheng Li Lili Ding Hongqiang Ren Ke Xu Yonggang Wu Dong Sheng 《环境科学学报(英文版)》2011,23(6):881-890
Chemical precipitation to form magnesium ammonium phosphate (MAP) is an effective technology for recovering ammonium
nitrogen (NH4
+-N). In the present research, we investigated the thermodynamic modeling of the PHREEQC program for NH4
+-N
recovery to evaluate the effect of reaction factors on MAP precipitation. The case study of NH4
+-N recovery from coking wastewater
was conducted to provide a comparison. Response surface methodology (RSM) was applied to assist in understanding the relative
significance of reaction factors and the interactive effects of solution conditions. Thermodynamic modeling indicated that the saturation
index (SI) of MAP followed a polynomial function of pH. The SI of MAP increased logarithmically with the Mg2+/NH4
+ molar ratio
(Mg/N) and the initial NH4
+-N concentration (CN), respectively, while it decreased with an increase in Ca2+/NH4
+ and CO3
2??/NH4
+
molar ratios (Ca/N and CO3
2??/N), respectively. The trends for NH4
+-N removal at different pH and Mg/N levels were similar to the
thermodynamic modeling predictions. The RSM analysis indicated that the factors including pH, Mg/N, CN, Ca/N, (Mg/N) (CO3
2??/N),
(pH)2, (Mg/N)2, and (CN)2 were significant. Response surface plots were useful for understanding the interaction effects on NH4
+-N
recovery. 相似文献
465.
Sedimentary record of polycyclic aromatic hydrocarbons in Lake Erhai,
Southwest China 总被引:1,自引:0,他引:1
Jianyang Guo Zhang Liang Haiqing Liao Zhi Tang Xiaoli Zhao Fengchang Wu 《环境科学学报(英文版)》2011,23(8):1308-1315
The temporal distribution of polycyclic aromatic hydrocarbons (PAHs) was investigated in a sediment core from Lake Erhal in Southwest China using gas-chromatography/mass spectrometry (GC/MS) method.The total organic carbon (TOC) normalized total PAHs concentrations (sum of US Environmental Protection Agency proposed 16 priority PAHs) ranged from 31.9 to 269 μg/g dry weight (dw),and were characterized by a slowly increasing stage in the deeper sediments and a sharp increasing stage in the upper sediments.The PAHs in the sediments were dominated by low molecular weight (LMW) PAHs,suggesting that the primary source of PAHs was low- and moderate temperature combustion processes.However,both the significant increase in high molecular weight (HMW) PAHs in the upper sediments and the vertical profile of diagnostic ratios pointed out a change in the sources of PAHs from low-temperature combustion to high-temperature combustion.The ecotoxicological assessment based on consensus-based sediment quality guidelines implied that potential adverse biological impacts were possible for benzo(ghi)perylenelene and most LMW PAHs.In addition,the total BaP equivalent quotient of seven carcinogenic polycyclic aromatic hydrocarbons (BaA,CHr,BbF,BkF,BaP,DBA and INP) was 106.1 ng/g,according to the toxic equivalency factors.Although there was no great biological impact associated with the HMW PAlls,great attention should be paid to these PAH components based on their rapid increase in the upper sediments. 相似文献
466.
467.
羟基多溴联苯醚对鲤鱼急性毒性及定量结构活性关系 总被引:1,自引:0,他引:1
羟基多溴联苯醚是一类具有环境风险的新兴污染物,它们已经在众多环境介质甚至人体内广泛存在。参照GB/T13267-91标准方法,采用静态生物急性毒性试验,测定了6种羟基多溴联苯醚(2′-OH-BDE7、4′-OH-BDE17、2′-OH-BDE28、2′-OH-BDE68、4′-OH-BDE90和2′-OH-BDE123)对普通鲤鱼的急性毒性96 h-LC50值,分别为697、1 130、854、550、644和522 ng.mL-1。除4′-OH-BDE17为高毒物质外,其他5种OH-PBDEs均为剧毒物质,高溴代的2′-OH-BDE123毒性最大。选用OH-PBDEs的KOW参数及由MOPAC软件PM3算法计算出的16个量子化学参数(EHomo、qBr+、ELumo等)为描述符,运用一元线性回归分析分别研究了96 h-LC50与他们之间的相关关系。结果表明:lgKOW和ELumo与6种羟基多溴联苯醚的96 h-lg LC50表现出较好的相关性,复相关系数均大于0.96,根据方程得到的96 h-lg LC50预测值与实验值基本相同,进一步对环境中广泛检出的其它OH-PBDEs的96 h-LC50值也进行了预测。 相似文献
468.
Fenton氧化在废水处理中的应用 总被引:2,自引:0,他引:2
综述了近年来Fenton氧化在废水处理领域的应用状况,对Fenton试剂氧化的机理和主要影响因素:温度、pH、反应时间、H2O2和Fe2+的投加量、H2O2/Fe2+量比以及反应动力学模型进行了简要介绍.最后探讨了Fenton氧化技术在废水处理领域现存不足之处及今后的发展趋势. 相似文献
469.
470.