我国10城市冬季大气颗粒物中多环芳烃污染及呼吸暴露风险评价

大气中颗粒物和多环芳烃对环境与人体健康危害较大,已引起社会各界的广泛关注。以我国10个城市2013年12月和2014年1月大气中空气动力学直径小于10μm的颗粒物(PM10)为研究对象,采用硅胶-氧化铝层析柱净化分离、气质联用仪分析的方法测定了27种多环芳烃(PAHs)的浓度水平,分析其谱分布及空间分布,并通过呼吸暴露途径估算了癌症病发增量(ILCRs)和人群归因危险度百分比(PAF)。结果表明,27种物质的总浓度为13.72~2 002 ng·m-3;在10个城市中晋中总浓度最高,厦门最低。PAHs空间污染水平呈现北方高于南方、东部沿海城市浓度相对较低的趋势。温度与总浓度有相关性。在27种PAHs中,占主导地位的单体为荧蒽(FLA,7.56%~19.8%),芘(PYR,6.72%~13.8%),艹屈(CHR,12.8%~19.6%)和苯并(k)荧蒽(Bk F,8.59%~15.5%),4者占到多环芳烃总浓度的42.1%~64.3%。根据研究区域苯并[a]芘(Ba P)人口加权浓度估算ILCRs范围为8.94×10-6~4.77×10-4,据此计算的PAFs为0.487%~13.2%,均值为3.44%,高于全国平均水平1.6%。上述研究结果为大气颗粒物中PAHs的研究提供重要的数据基础。     

Dynamics of mercury fluxes and their controlling factors in large Hg-polluted floodplain areas

Environmental pollution by mercury (Hg) is a considerable environmental problem world-wide. Due to the occurrence of Hg volatilization from their soils, floodplains can function as an important source of volatile Hg. Soil temperature and soil water content related to flood dynamics are considered as important factors affecting seasonal dynamics of total gaseous mercury (TGM) fluxes. We quantified seasonal variations of TGM fluxes and conducted a laboratory microcosm experiment to assess the effect of temperature and moisture on TGM fluxes in heavily polluted floodplain soils. Observed TGM emissions ranged from 10 to 850 ng m⁻² h⁻¹ and extremely exceeded the emissions of non-polluted sites. TGM emissions increased exponentially with raised air and soil temperatures in both field (R²: 0.49-0.70) and laboratory (R²: 0.99) experiments. Wet soil material showed higher TGM fluxes, whereas the role of soil water content was affected by sampling time during the microcosm experiments.     

景观富营养水体生态修复对浮游植物群落结构的影响

对以再生水为补给水源的北京稻香湖园林水系进行生态修复实验。通过对浮游植物群落和理化指标的分析,探讨浮游植物对生态修复的响应和修复效果。结果显示,生态修复实验实施后,TN、TP、COD和BOD5分别下降62.55%、66.42%、48.53%和40.95%,富营养程度明显降低;浮游植物密度和Chl-a含量分别下降86.1%和77.4%;Shan-non-Weaver物种多样性指数值从生态修复前低于2上升到2.74,且优势种群发生演替。相关分析表明:TP、PO4-P、pH与浮游植物密度呈极显著正相关(P(0.01);TN、NH4-N、NO2-N、COD和DO与浮游植物密度呈显著正相关(P(0.05);Chl-a含量与浮游植物密度呈极显著正相关(P(0.01)。浮游植物群落结构对城市富营养景观水系的生态修复措施表现出明显的响应。     

调理剂和通风方式对污泥生物干化效果的影响

采用了自主设计的污泥生物干化实验室模拟系统,研究了调理剂、物料配比和通风方式等实验条件对脱水污泥生物干化的影响效果。研究结果表明,与锯末相比,秸秆有利于反应物料温度的上升,含水率下降程度更大;利用秸秆调节污泥初始含水率在60%和65%的实验条件下时,物料的平均含水率分别下降了7%和6%,当初始含水率65%时,生物堆体的温度和含水率没有明显的变化;与连续通风相比较,间歇通风的实验条件有利于生物堆体的温度的升高和干化效果;在该实验中,最佳的生物干化条件是以秸秆为调理剂,初始含水率调至65%以下,以间歇方式进行通风。     

生态功能区划在县域可持续发展指标体系中的应用

在分析县域可持续发展指标体系特点的基础上,从生态功能区划依据的原则、目标等方面,深入论述了生态功能区划在县域可持续发展指标体系中的三方面作用,提出了应用生态功能区划结果对某一区域内不同县域的可持续发展状况分类别进行评价的观点。     

中国石油HSE专业标准化工作探讨

简要回顾了中国石油HSE标准化工作的历程,综合分析了HSE标准化工作面临的形势任务,对改进中国石油HSE标准化工作思路进行了探讨,明确了指导思想、遵循原则、重点工作,并提出做好HSE标准化工作要处理好四个方面关系的原则。     

Characterization of PM10 atmospheric aerosol at urban and urban background sites in Fuzhou city, China

Background

PM₁₀ aerosol samples were simultaneously collected at two urban and one urban background sites in Fuzhou city during two sampling campaigns in summer and winter. PM₁₀ mass concentrations and chemical compositions were determined.

Methods

Water-soluble inorganic ions (Cl^?, NO ₃ ^? , SO ₄ ^2? , NH ₄ ⁺ , K⁺, Na⁺, Ca²⁺, and Mg²⁺), carbonaceous species (elemental carbon and organic carbon), and elements (Al, Si, Mg, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, and Pb) were detected using ion chromatography, thermal/optical reflectance, and proton-induced X-ray emission methods, respectively.

Results

PM₁₀ mass concentrations, as well as most of the chemical components, were significantly increased from urban background to urban sites, which were due to enhanced anthropogenic activities in urban areas. Elements, carbonaceous species, and most of the ions were more uniformly distributed at different types of sites in winter, whereas secondary ion SO ₄ ^2? , NO ₃ ^? , and NH ₄ ⁺ showed more evident urban-background contrast in this season. The chemical mass closure indicated that mineral dust, organic matters, and sulfate were the most abundant components in PM₁₀. The sum of individually measured components accounted for 86.9?C97.7% of the total measured PM₁₀ concentration, and the discrepancy was larger in urban area than in urban background area.

Conclusion

According to the principal component analysis?Cmultivariate linear regression model, mineral dust, secondary inorganic ions, sea salt, and motor vehicle were mainly responsible for the PM₁₀ particles in Fuzhou atmosphere, and contributed 19.9%, 53.3%, 21.3%, and 5.5% of PM₁₀, respectively.     

混合硫酸盐还原菌代谢过程的影响因素

采用间歇实验,研究不同初始pH、Fe2+投加量、COD/SO24-及NO3-/SO24-比值等因素对SRB还原硫酸盐效果与速率的影响。实验结果表明:中性条件下(pH=7),硫酸盐的去除效果最佳,去除率达到84.66%,还原速率为15.07 mg/(L.h),在初始pH为4～9的范围内,体系具有较好的缓冲能力;当COD/SO24-比值为3时,反应209 h,硫酸盐去除率为85.33%,还原速率为8.16 mg/(L.h),随着反应的进行,体系的pH趋于中性;当溶液中有亚铁离子存在,且浓度为0～200 mg/L时可促进硫酸盐还原菌的生长,提高其对硫酸盐的去除率;NO3-对硫酸盐的还原有明显的抑制作用。     

SMBR处理含油废水出水COD数学模型

根据微生物生长动力学特征以及膜分离特征,建立恒通量下运行的一体式膜生物反应器系统出水COD数学模型,提出膜生物反应器处理效率的数学模型。以实验及模型为基础,分别对进水COD浓度控制在300、400、500 mg/L附近时经过反应器后COD的去除效率进行了比较。通过公式计算的数据和实验数据分析可得:COD去除率的公式计算值与实验结果比较吻合,相对偏差仅为0.0223,为膜系统有机物的去除效果估算提供了基础,可为该类工艺的参数选择与优化提供参考。     

强制循环厌氧反应器处理中低浓度废水

为解决内循环厌氧反应器在对低浓度有机废水处理时,因产气量不足、内循环量小而不能正常运行的问题,提出了强制循环反应器的概念,给出了设计方法。以低浓度、碱性印染工业废水为研究对象,进行了强制循环厌氧反应器的启动与运行的研究,得出了该反应器的最佳HRT和最佳外加循环量。结果表明:在高硫、低性状絮状厌氧泥为接种泥情况下,最佳外循环流量1 m3/h,最佳HRT为7 h时,FCR出水的T-COD和S-COD去除率分别为53.6%和58%。