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991.
生态文明是人类文明的一种形式,它以尊重和维护生态环境为主旨,以可持续发展为根据,以未来人类的继续发展为着眼点。这;仲文明观强调人的自觉与自律,强调人与自然环境的相互依存、相互促进、共处共融。生态文明要求人类尊重和爱护自然,将人类的生活建设得更加美好。生态文明的提出,是人们对可持:续发展问题认识深化的必然结果。  相似文献   
992.
资源和环境问题已成为各界关注的焦点,工业园区向现代生态工业园区建设转变是新形势生态文明下的必然要求。文章以内蒙古乌海市海勃湾区千里山工业园区为例,阐述了该工业园区建立生态型工业园区的可行性。  相似文献   
993.
湿式消解法对冷原子吸收测定生物样品中汞产生的干扰   总被引:3,自引:0,他引:3  
用不同的湿式消解法对多种生物样品的进行消解测定,分析了实验的干扰因素,并推荐了比较适宜的消解方法。  相似文献   
994.
995.
Ecological city is the advanced mode of harmonious development of city. Constant improvement is being made in the development of ecological city. However, building ecological city is an enormous project that calls for a huge amount of capital. The government fund is far from adequate. This paper probes into the fund issue and discusses in detail the mechanism of investment and financing in building ecological city from various aspects such as diversification of the investment subjects and the modes of financing.  相似文献   
996.
研究了土壤原样及其去锰氧化物、去铁氧化物、去有机质和去水溶性有机质(DOM)土壤样品对五氯酚(PCP)的吸附规律,分析了土壤及其主要化学组分对PCP的吸附机制.实验结果表明,Langmuir方程可较好地描述PCP在各土壤样品上的热力学吸附过程.PCP在土壤上的吸附行为与自身性质和土壤理化性质密切相关,有机质和铁氧化物对PCP的吸附起到促进作用,而锰氧化物和DOM则能在一定程度上抑制PCP的吸附.通过Langmuir方程得到的拟合结果,可判断PCP在各土壤样品上的最大吸附量为去锰氧化物土壤样品>去铁氧化物土壤样品>去DOM土壤样品>土壤原样>去有机质土壤样品.  相似文献   
997.
Desorption behavior of pyrene, phenanthrene and naphthalene from fullerene, single-walled carbon nanotubes (SWCNTs) and multi-walled carbon nanotubes (MWCNTs) was examined. Available adsorption space of carbon nanotubes (CNTs) was found to be the cylindrical external surface, neither the inner cavities nor inter-wall spaces due to impurities in the CNTs and restricted spaces (0.335nm) of the MWCNTs, respectively. Desorption hysteresis was observed for fullerene but not for CNTs. Deformation-rearrangement was proposed to explain the hysteresis of polycyclic aromatic hydrocarbons (PAHs) for fullerene, due to the formation of closed interstitial spaces in spherical fullerene aggregates. However, long, cylindrical carbon nanotubes could not form such closed interstitial spaces in their aggregates due to their length, thus showing no significant hysteresis. High adsorption capacity and reversible adsorption of PAHs on CNTs imply the potential release of PAHs if PAH-adsorbed CNTs are inhaled by animals and humans, leading to a high environmental and public health risk.  相似文献   
998.
999.
Limited information on the levels, inventory and fate of Organochlorine pesticides (OCPs) and Polybrominated diphenyl ethers (PBDEs) in the soils irrigated by sewage or wastewater is available. In this study, variation in concentrations, profiles and fate of OCPs and PBDEs were investigated using soil samples collected from a region irrigated by sewage, mixed water and clean water in the east of Beijing, China. No significant variation was observed among groups, except for penta-BDEs. The measured ΣOCPs and ΣPBDEs residues ranged from 6.4 to 171.2 ng g−1 (dw) and 501.9 to 3310.7 pg g−1 (dw), respectively. ΣDDTs and BDE-209 were the most abundant congeners accounting for about 76% of ΣOCPs and 93% of ΣPBDEs. Concentrations of hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethane (DDTs) and its major degradation products, and hexachlorobenzene (HCB) ranged from 1.2 to 11.4 ng g−1 (dw), 4.0 to 155.6 ng g−1 (dw) and 0.3 to 3.4 ng g−1 (dw), respectively. The major DDT degradation products were p,p′-DDT and p,p′-DDE. The major hexachlorocyclohexane (HCH) isomer in irrigated soils is β-HCH, reflecting its higher affinity to solids and resistance to degradation than other isomers. Both α-HCH/β-HCH and p,p′-DDT/p,p′-DDE ratios were log-normally distributed and negatively correlated to log(ΣHCHs) and log(ΣDDTs), respectively, suggesting no significant recent application of OCPs. Individual BDE congeners, ΣPBDEs and ΣOCPs were significantly correlated with total organic carbon (TOC). Moreover, a good correlationship between ΣPBDEs and black carbon (BC) was obtained but not between ΣOCPs and BC. Sewage irrigation did not have obvious effect on their contaminant levels and inventory of OCPs and PBDEs.  相似文献   
1000.
魏星  易杨柳 《四川环境》2008,27(5):31-34
对武汉市某小型浅水人工湖泊水质进行一年的理化监测并分析,结果显示:COD、BOD5均有季节性变化的规律;气温的变化影响湖水及底泥中微生物的活性;天然降水量不同对湖水稀释程度不同;底泥的污染物释放量受温度影响;该水体可生化性差。据此,提出保护湖水的措施。  相似文献   
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