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101.
Patagonia designs and distributes clothing for active use in the outdoors, and many of the people who work for Patagonia are avid climbers, skiers, surfers, and hikers. If the environment is destroyed, there will be no place for Patagonia's customers and employees to use its products. The types of products Patagonia makes and the personal commitment to the environment of its founder and employees make it unique. In the past few years, Patagonia has been systematically reviewing how the company's products and operations affect the environment. This article shows that even with Patagonia's unusual connection to the environment, the company is still finding that total quality environmental management is not easy. It takes analysis, planning, follow-through, and measurement; and even then, not all environmental efforts are successful.  相似文献   
102.
Zusammenfassung  Durch r?umlich integrale Bestimmung der Schadstofffrachten [1] und zeitlich integrales Monitoring mit Schadstoff-Dosimetern [1] l?sst sich Topographie und Bewegung von Schadstofffahnen im Grundwasser bestimmen. Konventionelle Methoden der Entnahme und Untersuchung von Wasserproben sind ungeeignet zur Erfüllung dieser Anforderungen. Sorptionsaktive Passivsammler, die für entsprechende Untersuchungen in der Gasphase konzipiert sind, eignen sich nicht zur Aquiferuntersuchung. Die Passivsammler zur Untersuchung im ungest?rten Aquifer sind zentraler Bestandteil eines Systems von Probenahme- und Messsonden, das die Autoren für das Monitoring chemischer und hydraulischer Wasser-Parameter entwickelt haben. Mit den Passivsammlern lassen sich die relativen Schadstofffrachten in beliebig enger tiefenorientierter Anordnung der Messpunkte und auch zeitlich integriert zur Gewinnung von vertikalen relativen Schadstofffracht-Profilen ermitteln. Organische und anorganische relative Schadstofffrachten k?nnen damit bestimmt werden. Die gaiasafe-Passivsammler sind einfach handhabbar und lassen sich nach standardisierten chemischen Analysenmethoden auswerten. Damit erfüllen sie eine Reihe wesentlicher Anforderungen an das zielführende Monitoring von Schadstofffahnen. Die Passivsammler sind auch geeignet für die In-situ-Untersuchung von ruhigen und bewegten Gew?ssern auch in gro?er Tiefe z.B. Abw?sserkan?le, Kl?ranlagen, Flüsse und Meere und insbesondere zum Nachweis von Kontaminanten und Spurenstoffen in Wasserproben. Online First: 10. 01. 2001  相似文献   
103.
Zusammenfassung  Arsenkampfstoffe sind in der Umwelt persistent und kontaminieren bis heute Boden und Grundwasser. In diesem Beitrag werden die chemischen Reaktionen der Arsenkamptstoffe Diphenylarsinchlorid (CLARK I), Phenylarsindichlorid (PFIFFIKUS), Ethylarsindichlorid (DICK) sowie von Chlorvinylarsinverbindungen (LEWISITE) dargestellt. Die M?glichkeiten der chemisch-analytischen Erfassung dieser chemischen Kampfstoffe als Originalsubstanzen und als Thiol-Derivate werden pr?sentiert.   相似文献   
104.
Agricultural production systems are recognised as a major source of atmospheric ammonia. Deposition of ammonia and ammonium may contribute to undesired changes in oligotrophic ecosystems. The continuous measurement of atmospheric ammonia requires expensive and sophisticated techniques and is performed only in a very restrict number of ambient air stations in Europe. Therefore, the application of passive samplers, which have the advantage of being easy to handle and cost-efficient, is useful. In the past the comparability of different passive samplers must be considered as rather scarce. In a joint European project under the leadership of the GSF-Forschungszentrum für Umwelt und Gesundheit, Neuherberg, in 1997 a comparison of different passive ammonia monitoring methods was carried out in a prealpine rural site near Garmisch-Partenkirchen. It was considered valuable to include not only well established systems but also methods still being developed. For the comparative test ten working groups with different methods took part. A wet annular denuder system, which has been developed by the Netherlands Energy Research Foundation for on-line measurement of atmospheric ammonia, served as reference of passive methods. The experiment, which started in June and finished in December, showed that most of the passive samplers fulfil the requirements and can be recommended for further measurements. Additional measurements of meteorological parameters were performed to check the influences of different weather conditions on passive sampling.  相似文献   
105.
We investigated a new kind of activated carbon named gaiasafe-Formstoff [1] as an agent for powerful heavy metal reduction. This activated carbon contains highly dispersed sulfide compounds. Our investigations with lead containing wastewaters showed an outstanding metal sulfide precipitation power of the new agent. The lead reduction rates are independent of wastewater parameters like lead concentration and complexing agent concentration. Contacted as powder or as a fixed bed with wastewater gaiasafe-Formstoff showed the best cleaning capacity in comparison to all other agents tested. Investigations with gaiasafe-Formstoff about its ability to reduce the contents of further heavy metals in wastewater are under way. The gaiasafe-Formstoff reaction products with wastewater represent an energy-rich and raw material-rich resource when fed to metallurgical processes.  相似文献   
106.
Ecotourism can incentivize social and environmental benefits through marine conservation, in parallel with efforts to better manage fisheries, coastal development, and other human pressures. In Mexico's Gulf of California and Baja California Peninsula (GCBP), marine ecosystems support tourism activities in many communities, but to date there have been no region-wide studies to estimate their benefits or identify key species. Based on data collected in this study, each year nature-based marine tourism in the GCBP results in 896,000 visits, US$518 million in expenditures and at least 3,575 direct jobs from formal operations. In interviews with operators, over 40 species groups were named as important; sea lions, whale sharks, whales, and marlin were the highest ranked, highlighting the importance of ecosystem-wide health for nature-based tourism sustainability. Local employment and the ability to make economic and conservation goals compatible were noted by operators as significant opportunities provided by nature-based marine tourism; challenges included pollution and declines in ecosystem health, a lack of infrastructure, poor resource management policies, and high operating costs. As nature-based marine tourism expands, a wider transition to true ecotourism, a focus on equitable benefits and collaboration between stakeholders and a cross-scale and ecosystem approach to management will be vital for achieving potential sustainable social, ecological and economic benefits.  相似文献   
107.
108.
In an equilibrium reaction, phenylarsine dichloride (PFIFFIKUS) reacts rapidly with alcohols at room temperature to yield phenylarsine bisether and phenylarsine chloride ether. The reactions, however, are not quantitative. The derivatives were identified using mass spectrometry.  相似文献   
109.
Levels of DDE, HEOD, PCBs and mercury were measured in Gannet eggs from several colonies around Britain during 1971-1987. At two colonies (Ailsa Craig and Bass Rock) sampled throughout this period, organochlorine levels declined between the early 1970s and 1983, and then increased again. The trends at other colonies, sampled over shorter periods, were generally consistent with those at Ailsa Craig and Bass Rock. Trends in mercury levels were more variable, and increases were observed at four colonies and declines at two. Some shell-thinning occurred in association with DDE contamination. However, levels of this chemical were too low to affect breeding success in the years concerned. The same was probably true of the other chemicals.  相似文献   
110.
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