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971.
Adsorption behavior of phosphate on Lanthanum(III) doped mesoporous silicates material 总被引:1,自引:0,他引:1
Jianda Zhang Zhemin Shen Wenpo Shan Ziyan Chen Zhijian Mei Yangming Lei Wenhua Wang 《环境科学学报(英文版)》2010,22(4):507-511
A series of lanthanum doped meosoporous MCM-41 (LaxM41, x is Si/La molar ratio) was prepared by sol-gel method. The surface
structure of the materials was investigated with X-ray diffraction and N2 adsorption/desorption technique. The content of La in the
materials was determined by ICP. It was found that the La content of La25M41, La50M41 and La100M41 was 7.53%, 3.89% and 2.32%,
respectively. The phosphate adsorption capacities increased with increasing amount of La incorporation. With 0.40 g La25M41 99.7%
phosphate could be removed. The effects of Si/La molar ratio, LaxM41 dose, pH, initial concentration of phosphate solution, co-ions
on phosphate adsorption were also evaluated. The phosphate adsorption kinetics of LaxM41 could be well-described by the pseudo
second-order model, and Langmuir isotherm fit equilibrium data much better than the Freundlich isotherm. 相似文献
972.
973.
974.
以2006年和2007年TM遥感影像为数据源,利用GIS技术,对南京市的土地利用动态变化进行了监测,结果表明,从2006~2007年,南京市耕地减少6723.72hm2,林地减少975.46hm2,而水域增加了1663.26hm2,建设用地增加了5191.11hm2,草地增加758.78hm2,未利用地增加了86.03hm2。与2006年相比南京市生态环境质量指数略有下降。 相似文献
975.
采用流体化床Fenton装置深度处理合成制药废水,通过正交试验确定了处理合成制药废水的最佳条件是HRT为20min,初始pH值为4.0,H2O2/CODcr(质量比)为4.0,H2O2/Fe2+(摩尔比)为15,且在最佳条件下出水CODcr稳定在80mg/L以下,可以达到《污水综合排放标准》(GB8979-1996)一级标准。同时将其与标准Fenton氧化法进行对比试验,结果显示流体化床FentonCODcr去除率可提高13%以上,污泥产生量可降低70%,运行成本可减低28%,稳定运行成本可以控制在3.0元/吨废水以内。 相似文献
976.
固定化菌剂处理含油废水的试验研究 总被引:1,自引:0,他引:1
探讨了固定化菌剂的接种量、曝气强度及温度等因素对废水中CODer去除率的影响.试验结果表明:在采用适当的曝气方式和曝气强度下,温度为30℃时,采用10%的固定化颗粒接种量,4种固定化产品对含油废水中CODer降解均有较好的效果. 相似文献
977.
978.
It is generally known that there are many endocrine disrupting compounds (EDCs) in the e uents from wastewater treatment
plants (WWTPs). Most research has focused on the occurrence of estrogenic or androgenic activities, while ignoring that there are
environmental chemicals disrupting thyroid system, which is essential for growth and development in both humans and animals. In
the present work, a two-hybrid yeast assay was conducted to evaluate the removal e ciencies of agonistic or antagonistic thyroid
receptor (TR) mediated e ects in di erent treatment processes of three WWTPs located in Beijing. We found no TR agonistic, but TR
antagonistic activities in all processes from the WWTPs. The TR antagonistic activities in organic extracts of water samples were then
calibrated regarding to a known TR-inhibitor, amiodarone hydrochloride (AH). The observed concentration of TR disrupting substances
ranged from 2.35 10??8 to 6.19 10??7 mol/L AH in Gaobeidian WWTP, 3.76 10??8 to 8.75 10??8 mol/L AH in Lugouqiao WWTP,
and 4.80 10??9 to 2.55 10??8 mol/L AH in Beixiaohe WWTP. Of the three WWTPs, the removal rates were 92.7%, 42.2%, and 23.1%
respectively. Industrial sewage may contain more TR disrupting substances compared with domestic sewage. The recipient waters were
found to contain considerable concentrations of TR disrupting substances that may cause adverse e ects on the exposed organisms. 相似文献
979.
PM2:5 samples were collected in a regional sampling network with three sites in Hong Kong and four sites in the adjacent inland
Pearl River Delta (PRD) or Guangdong Province during four months/seasons from 2002–2003. Trans-boundary transport between
Hong Kong and the inland PRD is inevitable under the influence of Asian monsoon. In summer, Hong Kong serves as the upwind
site of the inland PRD while during other seasons it is under the influence of continental emissions. Previous studies have recognized
the importance of using chemical signatures to differentiate local vs. regional contributions to air pollutants in Hong Kong such as the
CO/NOx ratio, ratios of different VOC species. In this study, detailed chemical speciation by gas chromatography-mass spectrometry
was performed with PM2:5 samples to identify new chemical signatures to distinguish aerosols in Hong Kong from those from the inland
PRD. Since Hong Kong is not influenced by the continental emissions from the inland PRD during summer, comparison focused on
chemical data obtained from this season for chemical signatures. The new ratios developed from the current study include LCPI/HCPI
ratio of alkanes (0.39 0.02 in Hong Kong vs. 0.78 0.08 in the inland PRD), pyrene to benzo[ghi]perylene ratio (0.97 0.21 in
Hong Kong compared to 0.20 0.06 in the inland PRD), and the ratio of 1,2-benzenedioic acid to 1,4-benzenedioic acid (1.8 0.1 in
Hong Kong vs. 0.6 0.05 in the inland PRD). Results from this study also revealed that Hong Kong was impacted by ship emissions
as reflected by substantially high V/Ni ratio (9 2) while this ratio was about 1–2 at all sites in the inland PRD, which is very close to
typical ratios from residual oil combustion. 相似文献
980.
It is generally known that there are many endocrine disrupting compounds (EDCs) in the effluents from wastewater treatment plants (WWTPs). Most research has focused on the occurrence of estrogenic or androgenic activities, while ignoring that there are environmental chemicals disrupting thyroid system, which is essential for growth and development in both humans and animals. In the present work, a two-hybrid yeast assay was conducted to evaluate the removal efficiencies of agonistic or antagonistic thyroid receptor (TR) mediated effects in different treatment processes of three WWTPs located in Beijing. We found no TR agonistic, but TR antagonistic activities in all processes from the WWTPs. The TR antagonistic activities in organic extracts of water samples were then calibrated regarding to a known TR-inhibitor, amiodarone hydrochloride (AH). The observed concentration of TR disrupting substances ranged from 2.35 × 10-8 to 6.19 × 10-7 mol/L AH in Gaobeidian WWTP, 3.76 × 10-s to 8.75 x 10-s mol/L AH in Lugouqiao WWTP,and 4.80 × 10-9 to 2.55 × 10-s mol/L AH in Beixiaohe WWTP. Of the three WWTPs, the removal rates were 92.7%, 42.2%, and 23.1% respectively. Industrial sewage may contain more TR disrupting substances compared with domestic sewage. The recipient waters were found to contain considerable concentrations of TR disrupting substances that may cause adverse effects on the exposed organisms. 相似文献