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61.
The present work focuses on the fate of two cancerostatic platinum compounds (CPC), cisplatin and carboplatin, as well as of two inorganic platinum compounds, [PtCl4]2− and [PtCl6]2− in biological wastewater treatment. Laboratory experiments modelling adsorption of these compounds onto activated sludge showed promising specific adsorption coefficients KD and KOC and Freundlich adsorption isotherms. However, the adsorption properties of the investigated substances were differing significantly. Adsorption decreased following the order cisplatin > [PtCl6]2− > [PtCl4]2− > carboplatin. Log KD-values were ranging from 2.5 to 4.3 , log KOC from 3.0 to 4.7.

A pilot membrane bioreactor system (MBR) was installed in a hospital in Vienna and fed with wastewater from the oncologic in-patient treatment ward to investigate CPC-adsorption in a sewage treatment plant. During three monitoring periods Pt-concentrations were measured in the influent (3–250 μg l−1 Pt) and the effluent (2–150 μg l−1 Pt) of the treatment plant using ICP-MS. The monitoring periods (duration 30 d) revealed elimination efficiencies between 51% and 63% based on averaged weekly input–output budgets. The derived log KD-values and log KOC-values ranged from 2.4 to 4.8 and from 2.8 to 5.3, respectively. Species analysis using HPLC-ICP-MS proofed that mainly carboplatin was present as intact drug in the influent and – due to low log KD – in the effluent of the MBR.  相似文献   

62.
Abstract: We reviewed the history and conservation of Sophora toromiro , a species that has been extinct in the wild since 1960 but has survived as scattered individuals in botanic gardens and private collections. The short-term conservation of S. toromiro is dependent on the management of surviving ex situ stocks. This is being achieved through international collaboration by a working group established to coordinate the conservation management of the species. Molecular evidence indicates that the species retains greater genetic variability than expected. The greatest amount of genetic variability was located in specimens outside botanic garden collections. No unmodified natural habitat survives on Rapa Nui ( Easter Island); so opportunities to establish a viable wild population are limited. Evidence from past reintroductions indicates that the best short-term opportunity for the species is through conventional horticultural management in botanic gardens and traditional farm plots on Rapa Nui. Some extinct-in-the-wild taxa (sensu World Conservation Union 1994), such as the Toromiro, retain genetic variability, and appropriate reintroduction sites exist. These taxa represent valid priorities for conservation management.  相似文献   
63.
Summary. The mint plant, Teucrium marum (family Labiatae), sometimes called cat thyme, contains two methylcyclopentanoid monoterpenes, dolichodial and teucrein. The former compound is potently anti-insectan. It is repellent to ants (Monomorium pharaonis) and induces preening reflexes in flies (Phormia regina) and cockroaches (Periplaneta americana). Evidence is presented suggesting that dolichodial, which is presumed to be the plant's chief defensive agent, is stored in the tiny epidermal capsules that beset the leaves. It is only when the leaves are injured (and the capsules ruptured) that the leaves become repellent. Teucrein, in contrast, has no anti-insectan potency. It is present predominantly in the leaf buds, unlike dolichodial, which is present mostly in mature leaves. It is argued that teucrein is the storage compound from which dolichodial is generated during leaf development.  相似文献   
64.
Environmental Modeling & Assessment - Benchmarking of different numerical models simulating groundwater flow and contaminant mass transport is the aim of the present study, in order to...  相似文献   
65.
This paper applies the Kuhn–Tucker model to estimate recreation demand of parks in Sicily. We estimate a fixed coefficient specification and a random coefficient specification to take into account heterogeneity across visitors. Estimates suggest a diversity of preferences across the population and that parks with higher level of quality attributes are more likely to be visited. We also simulate two sets of hypothetical policy scenarios to evaluate and compare the recreational value of each park and the welfare impacts of changes in a quality attribute.  相似文献   
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Management of water quality in drinking water catchments is of ongoing, high importance as nitrate concentrations are often still very high. We analysed the Augsburg catchment in Germany, a unique example where a result-oriented approach has been implemented. We investigated the historical evolution of the water protection programme, the result-oriented payment contracts with farmers, and farmer satisfaction with the contracts, based on interviews with the water utility and farmers as well as an analysis of the literature. Today, the water protection programme has been successfully implemented, and a significant reduction of nitrate concentration was achieved due to the following factors: (1) investment of non-negligible amounts of money for high compensation and remuneration payments, (2) different contract options, (3) farmers’ participation in the negotiation process for result-oriented payment contracts, (4) involvement of “outside” people and institutions in negotiation processes, (5) anticipation of starting a programme when nitrate levels were still far below legislative thresholds, and (6) a political and legislative framework allowing direct decisions by a water supplier.  相似文献   
69.
The use of petroleum-derived products should be avoided regarding the principles of green and sustainable chemistry. The work reported herein, is aimed at the liquefaction of pine shavings for the production of an environmentally-friendly polyol suitable to be used in the formulations of sprayable polyurethane foams. The biopolyols were obtained in high yield and were used to replace those derived from fossil sources, to produce more “greener” polyurethane foams and therefore, less dependent on petroleum sources, since the polyol component was substituted by products resulting from biomass liquefaction. The partial and fully exchange of the polyols was accomplished, and the results compared with a reference foam. The foams were afterward, chemical, physical, morphological, and mechanically characterized. The complete replacement of polyether polyol and polyol polyester has presented some similar characteristics as that used as a reference, validating that the path chosen for the development of more sustainable materials is on the right track for the contribution to a cleaner world.  相似文献   
70.
Intensifying global trade will result in increased numbers of plant pest and pathogen species inadvertently being transported along with cargo. This paper examines current mechanisms for prevention and management of potential introductions of forest insect pests and pathogens in the European Union (EU). Current European legislation has not been found sufficient in preventing invasion, establishment and spread of pest and pathogen species within the EU. Costs associated with future invasions are difficult to estimate but past invasions have led to negative economic impacts in the invaded country. The challenge is combining free trade and free movement of products (within the EU) with protection against invasive pests and pathogens. Public awareness may mobilise the public for prevention and detection of potential invasions and, simultaneously, increase support for eradication and control measures. We recommend focus on commodities in addition to pathways, an approach within the EU using a centralised response unit and, critically, to engage the general public in the battle against establishment and spread of these harmful pests and pathogens.  相似文献   
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