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301.
偕胺肟合铁(Ⅲ)纤维对α-萘酚的吸附   总被引:1,自引:0,他引:1  
以腈纶纤维为原料络合Fe3+制得偕胺肟合铁(Ⅲ)纤维,用其处理α-萘酚溶液,研究了偕胺肟合铁(Ⅲ)纤维对α-萘酚的吸附工艺条件和吸附动力学参数。实验结果表明,偕胺肟合铁(Ⅲ)纤维对α-萘酚的最佳吸附工艺条件为pH=3.0、吸附温度313.15K和吸附时间45min。在最佳工艺条件下,偕胺肟合铁(Ⅲ)纤维对α-萘酚的吸附在所研究的α-萘酚浓度范围内符合Freundlich等温吸附方程。未达到饱和吸附前,偕胺肟合铁(Ⅲ)纤维对α-萘酚的吸附符合一级反应动力学特征。  相似文献   
302.
文章阐述了陆梁油田在开发过程中采用油气混输技术、天然气发电机橇技术、锅炉烧湿气等技术,将伴生气回收率提高至92.10%;油气混输技术能够实现边缘区块油气全密闭输送;集中处理站锅炉燃烧湿气技术可增加处理站天然气外输气量,降低运行成本;小型活动天然气发电机橇的应用,可以充分利用富裕天然气降低生产成本,同时减少富裕天然气火炬放空燃烧量,收到了良好的经济效益和环境效益。  相似文献   
303.
高膜通量厌氧微网生物反应器处理生活污水的研究   总被引:3,自引:1,他引:2  
将动态膜技术与厌氧膜生物反应器相结合,形成一体式厌氧微网生物反应器(AnFBR),用于城市生活污水的处理,研究了在高膜通量条件下,AnFBR的运行情况和对生活污水的处理效果。结果表明,AnFBR在膜通量为72 L/(m2.h)条件下可连续稳定运行40 d;系统对COD平均去除率为58.4%,对TN和NH3-N有一定的去除效果;出水SS最高为15.0 mg/L,出水中污染物粒径在10μm以下;微网动态膜对小分子物质的截留量不高,但对分子量大于1 000 kU的物质有明显的截留效果,进水中的大部分大分子物质被转化为小分子物质;AnFBR在保留了泥水分离特点的情况下还具有结构简单、膜通量高、微网过滤周期长等优点。  相似文献   
304.
This study develops fine temporal (seasonal, day-of-week, diurnal) and vertical allocations of anthropogenic emissions for the TRACE-P inventory and evaluates their impacts on the East Asian air quality prediction using WRF-Chem simulations in July 2001 at 30-km grid spacing against available surface measurements from EANET and NEMCC. For NO2 and SO2, the diurnal and vertical redistributions of emissions play essential roles, while the day-of-week variation is less important. When all incorporated, WRF-Chem best simulates observations of surface NO2 and SO2 concentrations, while using the default emissions produces the worst result. The sensitivity is especially large over major cities and industrial areas, where surface NO2 and SO2 concentrations are reduced by respectively 3–7 and 6–12 ppbv when using the scaled emissions. The incorporation of all the three redistributions of emissions simulates surface O3 concentrations higher by 4–8 ppbv at night and 2–4 ppbv in daytime over broad areas of northern, eastern and central China. To this sensitivity, the diurnal redistribution contributes more than the other two.  相似文献   
305.
During the summertime of 2007/2008, carbon dioxide (CO2) and methane (CH4) fluxes across air–water interface were investigated in the littoral zones of Lake Mochou and Lake Tuanjie, east Antarctica, using a static chamber technique. The mean fluxes of CO2 and CH4 were ?70.8 mgCO2 m?2 h?1 and 144.6 μgCH4 m?2 h?1, respectively, in the littoral zone of Lake Mochou; The mean fluxes were ?36.9 mgCO2 m?2 h?1 and 109.8 μgCH4 m?2 h?1, respectively, in the littoral zone of Lake Tuanjie. Their fluxes showed large temporal and spatial dynamics. The CO2 fluxes showed a significantly negative correlation with daily total radiation (DTR) and a weakly negative correlation with air temperature and water temperature, indicating that sunlight intensity controlled the magnitude of CO2 fluxes from the open lakes. The CH4 fluxes significantly correlated with local air temperature, water table and total dissolved solids (TDS), indicating that they were the predominant factors influencing CH4 fluxes. Summertime CO2 budgets in the littoral zones of Lake Mochou and Lake Tuanjie were estimated to be ?152.9 gCO2 m?2 and ?79.7 gCO2 m?2, respectively, and net CH4 emissions were estimated to be 312.3 mgCH4 m?2 and 237.2 mgCH4 m?2, respectively. Our results show that shallow, open, alga-rich lakes might be strong summertime CO2 absorbers and small CH4 emitters during the open water in coastal Antarctica.  相似文献   
306.
The ambient air quality monitoring data of 2006 and 2007 from a recently established Pearl River Delta (PRD) regional air quality monitoring network are analyzed to investigate the characteristics of ground-level ozone in the region. Four sites covering urban, suburban, rural and coastal areas are selected as representatives for detailed analysis in this paper. The results show that there are distinct seasonal and diurnal cycles in ground-level ozone across the PRD region. Low ozone concentrations are generally observed in summer, while high O3 levels are typically found in autumn. The O3 diurnal variations in the urban areas are larger than those at the rural sites. The O3 concentrations showed no statistically significant difference between weekend and weekdays in contrast to the findings in many other urban areas in the world. The average ozone concentrations are lower in urban areas compared to the sites outside urban centers. Back trajectories are used to show the major air-mass transport patterns and to examine the changes in ozone from the respective upwind sites to a site in the center of the PRD (Wanqingsha). The results show higher average ozone concentrations at the upwind sites in the continental and coastal air masses, but higher 1 h-max O3 concentrations (by 8–16 ppbv) at the center PRD site under each of air-mass category, suggesting that the ozone pollution in the PRD region exhibits both regional and super-regional characteristics.  相似文献   
307.
Coal consumption is one important contributor to energy production, and is regarded as one of the most important sources of air pollutants that have considerable impacts on human health and climate change. Emissions of polycyclic aromatic hydrocarbons (PAHs) from coal combustion were studied in a typical stove. Emission factors (EFs) of 16 EPA priority PAHs from tested coals ranged from 6.25 ± 1.16 mg kg?1 (anthracite) to 253 ± 170 mg kg?1 (bituminous), with NAP and PHE dominated in gaseous and particulate phases, respectively. Size distributions of particulate phase PAHs from tested coals showed that they were mostly associated with particulate matter (PM) with size either between 0.7 and 2.1 μm or less than 0.4 μm (PM0.4). In the latter category, not only were more PAHs present in PM0.4, but also contained higher fractions of high molecular weight PAHs. Generally, there were more than 89% of total particulate phase PAHs associated with PM2.5. Gas-particle partitioning of freshly emitted PAHs from residential coal combustions were thought to be mainly controlled by absorption rather than adsorption, which is similar to those from other sources. Besides, the influence of fuel properties and combustion conditions was further investigated by using stepwise regression analysis, which indicated that almost 57 ± 10% of total variations in PAH EFs can be accounted for by moisture and volatile matter content of coal in residential combustion.  相似文献   
308.
利用城市污泥堆肥及建筑弃土种植麦冬研究   总被引:4,自引:3,他引:1  
将污泥堆肥产品分别与建筑弃土按0%、10%、20%、30%、40%和50%(湿重)的比例配制营养土,以麦冬为例进行180 d的栽培实验,分析了营养土对麦冬生长特性、植物体内及栽培土壤中营养学指标和重金属含量的变化规律,并通过模糊综合评价方法选择营养土较佳配制方案。实验结果表明:堆肥比例在50%时麦冬生物量增加率、新生芽数及地表部分比重为最大值,在30%时纺锤体肉质数减少率为最大值;随着营养土中堆肥比例增加,麦冬体内养分含量、重金属积累量随之增加,均在50%时达到最大值;栽培土壤养分越多损失量越多,各指残留率越低,同时全磷、全氮及K含量降低率较有效磷、碱解氮小得多,Cr降低率在5.20%~8.34%之间,Zn降低率在3.27%~17.35%之间;堆肥比例在40%以上的营养土对麦冬生长效果好,但较佳配制方案为堆肥产品占20%。  相似文献   
309.
Uptake, accumulation and translocation of caffeine by Scirpus validus grown in hydroponic condition were investigated. The plants were cultivated in Hoagland’s nutrient solution spiked with caffeine at concentrations of 0.5–2.0 mg L?1. The effect of photodegradation on caffeine elimination was determined in dark controls and proved to be negligible. Removal of caffeine in mesocosms without plants showed however that biodegradation could account for about 15–19% of the caffeine lost from solutions after 3 and 7 d. Plant uptake played a significant role in caffeine elimination. Caffeine was detected in both roots and shoots of S. validus. Root concentrations of caffeine were 0.1–6.1 μg g?1, while the concentrations for shoots were 6.4–13.7 μg g?1. A significant (p < 0.05) positive correlation between the concentration in the root and the initial concentrations in the nutrient solution was observed. The bioaccumulation factors (BAFs) of caffeine for roots ranged from 0.2 to 3.1, while BAFs for shoots ranged from 3.2 to 16.9. Translocation from roots to shoots was the major pathway of shoot accumulation. The fraction of caffeine in the roots as a percentage of the total caffeine mass in solution was limited to 0.2–4.4% throughout the whole experiment, while shoot uptake percentage ranged from 12% to 25% for caffeine at the initial concentration of 2.0 mg L?1 to 50–62% for caffeine at the initial concentration of 0.5 mg L?1. However, a marked decrease in the concentration of caffeine in the shoots between d-14 and d-21 suggests that caffeine may have been catabolized in the plant tissues subsequent to plant uptake and translocation.  相似文献   
310.
提出以二级矿化垃圾床为预处理单元,串联三维电极/电Fenton处理老龄垃圾渗滤液的组合工艺。矿化垃圾床处理后渗滤液中COD、氨氮、总磷、色度的去除率分别为80.55%、88.47%、98.32%和87.53%。通过单因素实验和正交实验,确定了三维电极/电Fenton法最佳工艺条件。经该组合工艺后,渗滤液中COD、氨氮、总磷和色度的最高去除率分别可达97.08%、95.24%、99.55%和96.92%,其中COD、总磷、色度这3个指标低于《生活垃圾填埋场污染控制标准》(GB16889.2008)表2规定的排放标准,为该组合工艺在实际中的应用提供重要理论依据。  相似文献   
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