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121.
EM对SBR反应器影响初试研究   总被引:2,自引:0,他引:2  
EM对SBR反应器的影响进行了初试研究,主要考察了在pH值为8.0,EM接种量为1∶10000(VEM:V污水)条件下,SBR反应器对生活污水中COD,T P,NH3-N的去除效果,以及对污泥性状改变的作用,得到了COD去除效果好于普通SBR(最高可达17.7%),NH3-N去除率两者持平,T P去除效果不明显,以及EM菌群能优化污泥性状的结论,并在此基础上确定了最佳运行模式,为下一步研究提供了一定的基础。  相似文献   
122.
We report a case of fetus in fetu presented as a complex intra-abdominal heterogeneous cystic lesion during ultrasound examination of the fetus at 25 weeks of gestation. Progressive growth of this mass was noted in the prenatal period. Fetal magnetic resonance imaging provided additional information to aid in the prenatal diagnosis. This allows proper counselling for the parents and helps to plan the postnatal management. Surgical excision was carried out in the early neonatal period and the diagnosis of fetus in fetu was confirmed. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
123.
Since the launch of its first satellite in 1972, the Landsat program has operated continuously for more than forty years. A large data archive collected by the Landsat program sig-nificantly benefits both the academic community and society. Thermal imagery from Landsat sensors, provided with relatively high spatial resolution, is suitable for monitoring urban thermal environment. Growing use of Landsat data in monitoring urban thermal environment is demonstrated by increasing publications on this subject, especially over the last decade. Urban thermal environment is usually delineated by land surface temperature (LST). However, the quantitative and accurate estimation of LST from Landsat data is still a challenge, especially for urban areas. This paper will discuss the main challenges for urban LST retrieval, including urban surface emissivity, atmospheric correction, radiometric calibration, and validation. In addition, we will discuss general challenges confronting the continuity of quantitative applications of Landsat observations. These challenges arise mainly from the scan line corrector failure of the Landsat 7 ETM + and channel differences among sensors. Based on these investigations, the concerns are to: (1) show general users the limitation and possible uncertainty of the retrieved urban LST from the single thermal channel of Landsat sensors; (2) emphasize efforts which should be done for the quantitative applications of Landsat data; and (3) understand the potential challenges for the continuity of Landsat observation (i.e., thermal infrared) for global change monitoring, while several climate data record programs being in progress.  相似文献   
124.
单力 《环境》2006,(5):102-103
引来西藏的水,润泽干渴的中国.这是军旅作家李伶在其报告文学《西藏之水救中国--大西线“再造中国”战略内幕详录》一书的主题.  相似文献   
125.
浑河抚顺市区段污染趋势分析   总被引:1,自引:0,他引:1  
采用各种模型,对2010年浑河抚顺市区段污染趋势预测分析。结果表明,经济社会增长的同时入河污染物量大副增加,水环境也严重超标,必须采取相应防治对策。  相似文献   
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127.
We present the first confirmed case by molecular analysis of a metaphyseal chondrodysplasia, McKusick type, in a 22-week fetus. Two novel compound heterozygous mutations, 64T> A and 79G > T, were found in the highly conserved regions of the RMRP gene. Twenty-two heterozygous g.1018 T> C mutations, two homozygous g.1018 T> C mutations, two heterozygous insertion mutations g.799_g.800insC and one heterozygous insertion mutation g.849_g.850insT were found among 100 normal controls. Careful radiological examination of the fetus for skeletal dysplasia allowed definitive diagnosis, proper genetic counselling and future prenatal diagnosis. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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129.
Since the 1980s, green purchasing/green procurement has increasingly been recognised as an effective means of addressing and reducing negative environmental impacts related to product production and consumption around the world. This paper reviews the procurement practices and policies of five Asian countries and Hong Kong, in the context of an international overview of green purchasing and practices. The extent of government involvement in green procurement is found to directly determine its overall effectiveness, and up-to-date information resources clearly enhance delivery and performance. A case study in Hong Kong demonstrates how public leadership on green procurement has advanced green procurement in the private sector.  相似文献   
130.
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