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51.
WANG Hong-kang 《环境科学学报(英文版)》2000,12(2):154-160
IntroductionNowweallconcernourselveswiththecontemporaryproblemsofoverpopulation,resourceexploitation,environmentalpollutionand... 相似文献
52.
《环境科学学报(英文版)》2023,35(3):798-810
Although point and nonpoint sources contribute roughly equal nutrient loads to lakes, their relative role in supporting algae growth has not been clarified. In this research, we have established a quantitative relationship between algae-available phosphorus (P) and P chemical fractions in sediments; the latter indicates the relative contribution of point versus nonpoint sources. Surface sediments from three large shallow lakes in eastern China, namely, the Chaohu, Taihu and Hongzehu Lakes, were sampled to assess their algae-available P and chemically extracted P fractions. The algae-available P primarily comes from iron/aluminium (hydr)oxide-bound P (Fe/Al-bound P), 45% of which is algae-available P. The ratio of Fe/Al-bound P to calcium compound-bound P (Ca-bound P) indicated the relative contribution of point to nonpoint sources, with the point sources contributing the majority of increased Fe/Al-bound P in sediments. Therefore, the reduction of point sources from urbanized areas, rather than nonpoint sources from agricultural areas that primarily contribute to the Ca-bound P fraction, should be prioritized to alleviate cyanobacterial algal blooms (CyanoHABs) in shallow lakes with sediment P as a potential source to support algae growth. With these important results, we proposed a conceptual model for “P-pumping suction” from sediments to algae to aid in the development of the criteria for sediment P concentrations in shallow lakes. 相似文献
53.
陈健 《石油化工环境保护》2004,27(2):6-7
结合工作实际,分析了油田企业面临的形势,提出了清洁生产工作中应注意的问题,注重实际效果,对验收评定标准也提出了自己的见解。 相似文献
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55.
发挥政府职能,转变用水观念,拓展筹资方式,开发回用水市场,降低成本等是企业解决污水回用问题的有效对策和措施.文章对泰皇岛港务集团公司污水回用工作的成功实践进行了分析,该实例表明企业完全可以开展污水回用工作,工程社会、经济、环境效益明显,实际运行经验可供其他企业借鉴. 相似文献
56.
膜生物反应器技术的研究和应用展望 总被引:25,自引:1,他引:25
膜生物反应器是将膜分离技术与生物上结合而开发的新型系统,该文就膜生物反应器的特征、研究现状、不同形式反应器的技术参数与处理效果等。进行了综述、由于膜生物反应器具有明显的优点,故愈来愈受到人们的重视、成为研究的热点之一。膜生物反应器的研究和范围不断拓宽,有的已进入污水处理实用阶段,建议今后在开发适合于分离的特种膜方面,在组件形式,操作条件,清洗方式等对膜通量的影响方面,以及生物作用与膜分离工艺的相互 相似文献
57.
陡坡地灌桑垄槽栽培研究结果,免除土壤侵蚀的危害,其50cm、100cm土壤中,比对照区持水量高10.20%~33.67%、8.27%~65.37%,含全氮率为对照的90%,含全磷率高2.9%、26.2%,含全钾率高3.18%、8.01%,而水解氮均为对照的61.5%,速效磷高较对照39.02%、97.72%,速效钾为对照的91.48%、92.54%。公顷产桑叶量和蚕茧量均较对照高5~10倍,经济效益较对照高11.88倍。 相似文献
58.
IntroductionMostofnitroaromaticsareimportantenvironmentalpollutants.ThecarpisthemajoreconomicfishinChinaandisoneofthefivestan?.. 相似文献
59.
Frances R. Sweetman Kenneth M. Gibson Lawrence Sweetman Ph.D William L. Nyhan Homer Chin William Swartz Oliver W. Jones 《黑龙江环境通报》1986,6(3):187-194
We have documented the presence of five mitochondrial enzymes in samples of chorionic villus tissue and measured the levels of activity. Three of the enzymes catalyse biotindependent reactions. These are propionyl-CoA carboxylase, 3-methylcrotonyl-CoA carboxylase and pyruvate carboxylase. the other enzymes. 4-aminobutyric acid aminotransferase and succinic semialdehyde dehydrogenase, are involved inthe degradation of the central inhibitory neurotransmitter GABA. Distinct diseases in whichthere is deficiency of each of these enzymes have been documented in man. Significant levels of activity were observed for all five enzymes in chorionic villus tissue. This methodology should permit early prenatal diagnosis of deficiencies of these enzymes by chorionic villus biopsy in the first trimester. 相似文献
60.
R. B. H. Schutgens G. Schrakamp R. J. A. Wanders H. S. A. Heymans H. W. Moser A. E. Moser J. M. Tagers H. V. D. Bosch P. Aubourm 《黑龙江环境通报》1985,5(5):337-344
Prenatal diagnosis of the cerebro-hepato-renal (Zellweger) syndrome has been performed in 10 pregnancies at risk by measuring both the activity of acyl CoA: dihydroxyacetonephosphate acyltransferase (DHAP-AT) and the de novo plasmalogen biosynthesis, either in cultured amniotic fluid cells or in fibroblasts cultured from a chorionic villus biopsy. In 7 of the pregnancies both tests indicated no abnormality. All 7 continued to term and normal infants were delivered. However, in amniotic fluid cells from 2 fetuses affected by Zellweger syndrome unequivocal differences from control values were found. The activity of DHAP-AT was clearly deficient and the de novo plasmalogen biosynthesis was impaired. In one pregnancy at risk prenatal diagnosis was performed during the first trimester by measuring both the DHAP-AT activity and the de novo plasmalogen biosynthesis in fibroblasts cultured from a chorionic villi biopsy. From the deficient DHAP-AT activity and the impaired de novo plasmalogen biosynthesis it was concluded that the fetus was affected. This was confirmed biochemically after induced abortion. It can be concluded that measurement of the DHAP-AT activity and the de novo plasmalogen biosynthesis provides convenient methods for the early prenatal detection of Zellweger syndrome. 相似文献