国家清洁生产中心的金融可持续性:洪都拉斯国家清洁生产中心的经验

洪都拉斯国家清洁生产中心于2000年成立,加拿大国际开发署(CIDA)为中心前五年的运行提供资助.CIDA还在1998年资助了中心的可行性研究和项目设计.顾问们制定的实施战略把金融可持续性定为一个主要目标.推荐了用于成本回收的详细机制,以及一些中心服务费用分担办法.剩余资金将被加入可持续性基金.在这一方面已经取得了重大进展.到2003年这一基金的数目之大导致CIDA的捐款仅占中心业务预算的50%;剩余部分来自参与企业.本文介绍了中心所执行战略的基本内容、挑战、进展和在努力实现金融可持续性的过程中获得的经验.     

Fertilization success and sexual behavior in male medaka, Oryzias latipes, exposed to tributyltin

We evaluated the effects of tributyltin (TBT), polychlorinated biphenyls (PCBs), and a mixture of TBT and PCBs on reproduction, gonadal histology, and sexual behavior in Japanese medaka (Oryzias latipes). We administered TBT (1 microg g(-1) body weight [b.w.] daily), PCBs (1 microg g(-1) b.w. daily), or both to medaka for 3 weeks. We assessed reproductive success during week 3 and the sexual behavior of male medaka after the exposure period. Fertilization success was significantly decreased in groups that received TBT. The profiles of fertility developed a bimodal distribution in the TBT and TBT+PCBs groups, and the numbers of males that performed "following" and "dancing" were significantly decreased in the TBT+PCBs group. The frequency of "dancing" also decreased after treatment with TBT, whereas fish that received PCBs only showed no difference in sexual behavior. Testes that had oocytes showed normal spermatogenesis, even though two of the five males treated with TBT+PCBs had some indication of testis-ova, which did not occur in any other group. Our results indicate that TBT, but not PCBs, affects sexual behavior and reproduction in medaka.     

Brominated flame retardants and organochlorine pollutants in aquatic and terrestrial predatory birds of Belgium: levels, patterns, tissue distribution and condition factors

Liver and muscle samples from 7 species of aquatic and terrestrial predatory birds from Flanders (Belgium) were analysed for polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs) and organochlorine pesticides (OCPs). PCBs were the predominant compounds in our samples, which showed highest concentrations in the liver of barn owl (Tyto alba) and sparrowhawk (Accipiter nisus) (up to 1000 microg/g lipid weight). PBDEs could be determined in most samples at lower concentrations than PCBs (up to 64 microg/g lipid in sparrowhawk liver). Sparrowhawks had the highest levels of hexachlorobenzene, DDTs and PBDEs. In contrast, kestrels (Falco tinnunculus) had relatively low levels of most measured organochlorines. BDE 47 was the most abundant congener in heron (Ardea cinerea) and grebe (Podiceps cristatus), while BDE 47, 99 and 153 were equally important in the terrestrial species. BDE 183 and BDE 209 were only measured in the terrestrial birds. These results indicate that terrestrial birds may be more exposed to higher brominated BDE congeners than aquatic species.     

Numerical simulation of reactive processes in an experiment with partially saturated bentonite

Bentonites are preferred materials for use as engineered barriers for high-level nuclear waste repositories. Simulation of geochemical processes in bentonite is therefore important for long-term safety assessment of those repositories. In this work, the porewater chemistry of a bentonite sample subject to simultaneous heating and hydration, as studied by Cuevas et al. [Cuevas, J., Villar, M., Fernández, A., Gómez, P., Martín, P., 1997. Porewaters extracted from compacted bentonite subjected to simultaneous heating and hydration. Applied Geochemistry 12, 473-481.], was assessed with a non-isothermal reactive transport model by coupling the geochemical software PHREEQC2 with the object-oriented FEM simulator GeoSys/RockFlow. Reactive transport modelling includes heat transport, two-phase flow, multicomponent transport and geochemical reactions in the liquid phase, i.e. ion exchange, mineral dissolution/precipitation and equilibrium reactions. Simulations show that the easily soluble minerals in bentonite determine the porewater chemistry. Temperature affects both two-phase flow and geochemical reactions. Porosity change due to dissolution/precipitation is low during the experiment. However, changes of the effective porosity caused by bentonite swelling can be very large. The simulated results agree well with the experimental data.     

用石墨炉原子吸收分光光度法测定海水中的锡及三取代有机锡化合物

业已建立了一种基于采用可放大信号的介质的石墨炉原子分光光度法的分析方法,来测定海水中的无机锡和两种三取代有机衍生物.采用捕集于石墨化碳黑上的富集法(富集因子高达8×10~4)和在小硅胶交换柱上的分离法,可分别测定2×10~(-12)和2.8×10~(-12)mol/L的三苯基锡和三丁基锡化合物.未吸附在石墨化碳黑上的无机锡,利用其吡咯烷二硫代氨基甲酸盐络合物的液一液萃取法,使其进入二氯甲烷,而从基体液中分离出来.本法测定ng/L级含量时的回收率高(≥95%),精密度好(≤5%).     

Effects of sampling techniques on physical parameters and concentrations of selected persistent organic pollutants in suspended matter

This study focusses on the effect of sampling techniques for suspended matter in stream water on subsequent particle-size distribution and concentrations of total organic carbon and selected persistent organic pollutants. The key questions are whether differences between the sampling techniques are due to the separation principle of the devices or due to the difference between time-proportional versus integral sampling. Several multivariate homogeneity tests were conducted on an extensive set of field-data that covers the period from 2002 to 2007, when up to three different sampling techniques were deployed in parallel at four monitoring stations of the River Rhine. The results indicate homogeneity for polychlorinated biphenyls, but significant effects due to the sampling techniques on particle-size, organic carbon and hexachlorobenzene. The effects can be amplified depending on the site characteristics of the monitoring stations.     

Spatial trends of polybrominated diphenyl ethers in avian species: utilization of stored samples in the Environmental Specimen Bank of Ehime University (es-Bank)

The present study determined concentrations and patterns of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in specimens of open sea, and Japanese coastal and inland avian species, which have been stored in the Environmental Specimen Bank of Ehime University (es-Bank), to examine the spatial trends. PBDEs and PCBs were detected in all the muscle samples analyzed, suggesting that PBDE pollution has spread even to the remote open sea areas, as in the case of PCBs. Japanese coastal and inland birds accumulated higher concentrations of PBDEs than open sea birds. In addition, higher PBDE/PCB concentration ratios were observed in Japanese coastal and inland birds than in open sea birds, indicating the input of PBDEs into the Japanese terrestrial environment. Compositions of PBDEs varied among avian species with a predominance of BDE47 or BDE153. This could be due to differences in their habitat, food habit and/or biotransformation capacity of PBDEs.     

Chemical solutions for greywater recycling

Greywater recycling is now accepted as a sustainable solution to the general increase of the fresh water demand, water shortages and for environment protection. However, the majority of the suggested treatments are biological and such technologies can be affected, especially at small scale, by the variability in strength and flow of the greywater and potential shock loading. This investigation presents the study of alternative processes, coagulation and magnetic ion exchange resin, for the treatment of greywater for reuse. The potential of these processes as well as the influence of parameters such as coagulant or resin dose, pH or contact time were investigated for the treatment of two greywaters of low and high organic strengths. The results obtained revealed that magnetic ion exchange resin and coagulation were suitable treatment solutions for low strength greywater sources. However, they were unable to achieve the required level of treatment for the reuse of medium to high strength greywaters. Consequently, these processes could only be considered as an option for greywater recycling in specific conditions that is to say in case of low organic strength greywater or less stringent standards for reuse.