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2001年欧洲铝工业委托乌珀塔尔研究所完成一个项目叫做“朝着可持续性发展的铝工业:利益相关者的期望值和核心指标“.该项目的目的是检查可持续性议程和利益相关者的期望值.其后为了用来测定企业的可持续行为建立了一个指标框架.参与的利益相关者能够看到他们的投入正在被采用.本文介绍了开发这个部门的可持续性指标系统的论证经验,并陈述了主要的可持续发展主题.  相似文献   
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Promiscuity is traditionally considered to increase only male reproductive success but, more recently, female benefits are also assumed to be the driving force for promiscuous mating. The yellow-toothed cavy (Galea musteloides) is characterised by an extremely high degree of multiple paternity (>80%), and females have greater offspring viability after mating multiple males. However, so far it is not clear whether or not it is the female's decision that leads to mating with more than one male. To elucidate the female's role in bringing about promiscuity, female yellow-toothed cavies were given the choice between four different males each, in a mate-choice apparatus that simultaneously prevented monopolisation and harassment of the females by the males. In 10 of the 12 choice tests, mating occurred. Nine of these ten females actively sought copulations with more than one male, and their mating behaviour was displayed in a way that might have favoured the mixing of sperm. At the same time, they significantly preferred heavier and more frequently courting males. These results show that female yellow-toothed cavies are actively involved in mating with more than one male. Thus, the present study is the first to show that in a species in which females produce more viable offspring as a consequence of polyandrous mating, these females are indeed motivated to actively bring about promiscuity. Nevertheless, females are selective in the choice of their mates. Thus, both sperm competition and direct female choice seem to be important for the increased offspring viability due to promiscuous mating.  相似文献   
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A method has been developed and validated in order to assess the occurrence of the alkylphenols tert-octylphenol and the isomers of technical nonylphenol as well as bisphenol A in gasphase and aerosol samples of a remote area. Gasphase samples were adsorbed to XAD2 resin, aerosol samples were taken on glass fiber filters. After ultrasonic extraction, clean-up by column chromatography and silylation of the analytes, ten nonylphenol peaks were quantified separately using a GC-MSD-SIM method. The absolute limits of detection and determination are in the range of a few pg per compound, which is a prerequisite for the quantification of the analytes in relatively unpolluted air. The precision of the whole analytical method is in the range of 1-17% and the recoveries range from 57% to 80%. Problems were encountered during method development due to the tendency of the analytes to sorb to glass surfaces. Silanisation of glassware was crucial to achieve acceptable recoveries. The widespread use of the analytes in plastic resins resulted in sample contamination. For this reason a careful choice of sampling material was necessary. Measured concentrations in gasphase samples (lower nanogram per m3 range) and aerosol samples (upper picogram per m3 range) are one to three orders of magnitude below already published concentrations.  相似文献   
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