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881.
Wilhelm K?nig 《Umweltwissenschaften und Schadstoff-Forschung》1999,11(6):374-376
Ohne Zusammenfassung 相似文献
882.
883.
Bj?rn Johnson 《Waste management & research》2007,25(3):208-213
Innovative cities are essential for the economic growth and development of countries. At the same time, however, social and environmental problems related to city growth can be serious threats to the full realisation of the socio-economic contribution that cities can make. City environments thus often provide both new problems and the creative and diverse environments, which make it possible to solve them. The question of whether or not sustainable development is possible largely will be answered in cities. This is also the case for problems related to waste management. Landfills may be located in the countryside, but if a country is to reduce environmental costs, the results will rest on the innovation power of cities. In this paper it is argued that the notion of a 'system of innovation' is helpful in understanding the factors that shape the processes of innovation and that determine the extent to which environmental problems may be solved. In this context, institutional innovation and political innovation as compared to technical innovation are of special importance. 相似文献
884.
Marta Diez-Valcarce Petros Kokkinos Kirsi S?derberg Martijn Bouwknegt Kris Willems Ana Maria de Roda-Husman Carl-Henrik von Bonsdorff Maria Bellou Marta Hernández Leena Maunula Apostolos Vantarakis David Rodríguez-Lázaro 《Food and environmental virology》2012,4(2):73-80
In this study, the prevalence of different enteric viruses in commercial mussels was evaluated at the retail level in three European countries (Finland, Greece and Spain). A total of 153 mussel samples from different origins were analysed for human norovirus (NoV) genogroups I and II, hepatitis A virus (HAV) and hepatitis E virus (HEV). Human adenovirus (HAdV) was also tested as an indicator of human faecal contamination. A full set of controls (such as sample process control, internal amplification controls, and positive and negative controls) were implemented during the process. The use of a sample process control allowed us to calculate the efficiencies of extraction, which ranged from 79 to 0.5?%, with an average value of 10?%. Samples were positive in 41?% of cases, with HAdV being the most prevalent virus detected (36?%), but no significant correlation was found between the presence of HAdV and human NoV, HAV and HEV. The prevalences of human norovirus genogroup II, HEV and human NoV genogroup I were 16, 3 and 0.7?%, respectively, and HAV was not detected. The estimated number of PCR detectable units varied between 24 and 1.4?×?103?g?1 of digestive tract. Interestingly, there appeared to be a significant association between the type of mussel species (M. galloprovincialis) and the positive result of samples, although a complete overlap between country and species examined required this finding to be confirmed including samples of both species from all possible countries of origin. 相似文献
885.
Recovery of iron oxide and calcium chloride from an iron-rich chloride waste using calcium carbonate
Yang Hee Jung Yoon Seok Won Kim You Jin Park Hee Sun Huh Seok Hur Nam Hwi 《Journal of Material Cycles and Waste Management》2021,23(1):222-230
Journal of Material Cycles and Waste Management - The ilmenite-chloride process has used for the production of TiCl4 from the ilmenite (FeTiO3) ore, which produces cyclone dust containing mostly... 相似文献
886.
The practice of environmental planning and protection frequently necessitates the quantification of ecological diversity. Traditional ‘ecological diversity indices’ are based on the abundances of species present. However, such indices are insensitive to taxonomic or similar differences. With equal species abundances they measure the species richness (species number) only. Conversely, so-called ‘biodiversity indices’ are based on species differences, but are insensitive to the abundance conditions. The quadratic entropy index is the only ecological diversity index, the value of which reflects both the differences ‘and’ abundances of the species. When a species list is given without abundance data, then, using the quadratic entropy index and postulating equal abundances, one gets the only biodiversity index derived from a traditional ecological index of diversity. Its extensive form is identical with the sum of differences or distances between the species present. This index trivially satisfies set monotonicity, an important property for biodiversity indices. 相似文献
887.
888.
S?ren Furbo Anne G. Mortensen Bente Laursen Carsten Christophersen Inge S. Fomsgaard 《Chemoecology》2011,21(2):59-66
Degradation of biochanin A, 400 μg (1.41 μmol) per gram of dry soil, was studied and the initial degradation products, dihydrobiochanin
A, pratensein and genistein were identified and quantified. The maximum concentrations of these compounds were determined
as 166 pmol/g dry soil after 2 days of incubation, 175 pmol/g dry soil after 1 day and 1,236 pmol/g dry soil after 1 day,
respectively. Biochanin A and the initially formed products degrade too fast to be responsible for clover soil sickness (DT90 <20 days), but could be precursors for the responsible compounds. The immediate degradation products from biochanin A are
all biologically active and are the prime candidates for a reduction of weed pressure caused by clover. 相似文献
889.
Yong Ju Choi Young-Jin Kim Kyoungphile Nam 《Environmental pollution (Barking, Essex : 1987)》2009,157(8-9):2197-2202
This study investigated the ability of a saponin-based microbubble suspension to enhance aerobic biodegradation of phenanthrene by subsurface delivery. As the microbubble suspension flowed through a sand column pressure buildup and release was repeatedly observed, which delivered oxygen to the less permeable regions. Burkholderia cepacia RPH1, a phenanthrene-degrading bacterium, was mainly transported in a suspended form in the microbubble suspension. When three pore volumes of the microbubble suspension containing B. cepacia RPH1 was introduced into a column contaminated with phenanthrene (100 mg/kg), the oxygen content declined to 5% from an initial value of 20% within 5 days and correspondingly, 34.4% of initial phenanthrene was removed in 8 days. The addition of two further three pore volumes enhanced the biodegradation efficiency by a factor of 2.2. Our data suggest that a saponin-based microbubble suspension could be a potential carrier for enhancing the aerobic biodegradation under an oxygen-limiting environment. 相似文献
890.