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以稻壳为原料制备铁铜改性生物炭(FCBC300),采用扫描电子显微镜、元素组成分析仪、X-射线衍射光谱仪、傅里叶红外光谱仪对其进行了系列基础理化性质表征,通过批量吸附实验研究了FCBC300在不同pH和干扰离子及有机物腐殖酸(HA)等条件下对双氯芬酸钠(DCF)的去除效果和吸附机制。结果表明,改性后稻壳炭表面负载Fe3O4、γ-Fe2O3和CuO,芳香性增强、亲水性降低,对DCF的吸附性能大幅度提升。pH=5~9条件下,改性稻壳炭对DCF的吸附量约是未改性稻壳炭的20倍,吸附机制以静电作用为主;PO43-的存在对吸附几乎无影响,SO42-、Cl-和HCO3-对DCF的去除虽有轻微抑制作用,但去除率下降幅度均低于5%,HA存在则明显抑制吸附能力;FCBC300对DCF的吸附过程,更符合准一级动力学模型和Langmuir等温吸附模型,预测最大吸附量为4... 相似文献
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Increasing amounts of animal and municipal wastes are being composted before land application to improve handling and spreading characteristics, and to reduce odor and disease incidence. Repeated applications of composted biosolids and manure to cropland may increase the risk for P enrichment of agricultural runoff. We conducted field research in 2003 and 2004 on a Fauquier silty clay loam (Ultic Hapludalfs) to compare the effects of annual (since 1999) applications of composted and uncomposted organic residuals on P runoff characteristics. Biosolids compost (BSC), poultry litter-yard waste compost (PLC), and uncomposted poultry litter (PL) were applied based on estimated plant-available N. A commercial fertilizer treatment (CF) and an unamended control treatment (CTL) were also included. Corn (Zea mays L.) and a cereal rye (Secale cereal L.) cover crop were planted each year. We applied simulated rainfall in fall 2004 and analyzed runoff for dissolved reactive P (DRP), total dissolved P (TDP), total P (TP), total organic C (TOC), and total suspended solids (TSS). End of season soil samples were analyzed for Mehlich-3 P (M3P), EPA 3050 P (3050P), water soluble P (WSP), degree of P saturation (DPS), soil C, and bulk density. Compost treatments significantly increased soil C, decreased bulk density, and increased M3P, 3050P, WSP, and DPS. The concentration of DRP, TDP, and TP in runoff was highest in compost treatments, but the mass of DRP and TDP was not different among treatments because infiltration was higher and runoff lower in compost-amended soil. Improved soil physical properties associated with poultry litter-yard waste compost application decreased loss of TP and TSS. 相似文献
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Kucklick JR Krahn MM Becker PR Porter BJ Schantz MM York GS O'Hara TM Wise SA 《Journal of environmental monitoring : JEM》2006,8(8):848-854
Since 1987, the Alaska Marine Mammal Tissue Archival Project (AMMTAP) has collected tissues from 18 marine mammal species. Specimens are archived in the National Institute of Standards and Technology's National Biomonitoring Specimen Bank (NIST-NBSB). AMMTAP has collected blubber, liver and/or kidney specimens from a number of ringed seals (Phoca hispida) from the areas near Nome and Barrow, Alaska and walruses (Odobenus rosmarus) from several locations in the Bering Sea. Thirty-three ringed seal and 15 walrus blubber samples from the NIST-NBSB were analyzed for persistent organic pollutants (POPs). The compounds determined included PCBs (28 congeners or congener groups), DDT and related compounds, hexachlorobenzene (HCB), hexachlorocyclohexane isomers (HCHs), chlordanes, dieldrin, and mirex. POP concentrations in ringed seal blubber were significantly higher in Barrow than in Nome when statistically accounting for the interaction of age and gender; HCB, however, was not statistically different between the two locations. Unlike males, POP concentrations and age were not significantly correlated in females probably as a result of lactational loss. POP concentrations in walrus blubber were lower than in ringed seal blubber for SigmaPCBs, chlordanes, and HCHs, but higher for dieldrin and mirex. POP concentrations in ringed seals and walrus from Alaska provide further evidence that the western Arctic tends to have lower or similar POP concentrations compared to the eastern Canadian Arctic. 相似文献
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石英压电晶体在分析化学中用来检测与测定微量物质,特别是气体,有不少报道,Hlavay已做了详细评述。石英晶体金属膜涂层电极重量与频率变化关系可用公式△F=-2.3×10~6F~2(△M_s/A)表示。式中△F为涂层重量变化引起频率的变化(Hz),F为石英晶片频率(MHz),△Ms为涂层质量(g),A为涂层面积(cm~2)。King应用与被测气体有选择性吸附的材料涂复于晶体的金属膜电极上,被测气体吸附后由△Ms变化导致晶体频率变化,从而设计出供气相色谱用检测器。 相似文献
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社区是社会治理的基本单位,而社区种种事故对居民和家庭造成的伤害、损失,往往成为影响社区乃至社会和谐、稳定的重要因素。HSE管理体系是一种先进的体系化、规范化、科学化、制度化的管理方法,在大型石油石化企业得到广泛应用。本文以华北油田矿区为研究对象,对社区风险特点、如何构建与实施以风险管控为核心的HSE管理体系进行研究,从而为建设社区安全长效机制提供了依据,并对减少社区事故与伤害提出了对策。 相似文献
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石油污染土壤中高效石油烃降解菌Y-16的筛选及其降解性能 总被引:4,自引:1,他引:3
通过富集和驯化培养从石油污染的土样中筛选出一株高效石油烃降解菌Y-16,其对胜利原油7 d降解率达到51.98%。在好氧条件下,对Y-16菌株的最优降解条件进行了探索,结果表明,在pH值8.0,温度30℃,接种量10%,摇床转数160 r/m in和3 000~7 000 mg/L的底物浓度下,Y-16菌株的最高降解率可达到60.34%。通过Y-16菌株对石油烃降解规律的探索,发现Y-16菌株对石油烃的降解符合一级反应动力学模型。 相似文献