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291.
Michael V. Martin 《Journal of the American Water Resources Association》1984,20(2):219-221
ABSTRACT: Congress, with the support of the Reagan Administration, is considering the imposition of a user fee on deep draft waterways and ports. Two major bills emerged in the 98th Congress and proposes a tax on import-export value while the other proposes a tax on import-export tonnage. This paper proposes and discusses another user fee alternative, a vessel licensing system. It outlines the advantages of such a fee system under a set of assumed objectives and discusses the range of possible license charge levels under a cost recovery target of $250 million. 相似文献
292.
Peter Viebahn Michael Matthies Werner Berens und Bodo Rieger 《Umweltwissenschaften und Schadstoff-Forschung》1999,11(5):303-307
Zusammenfassung Grundlage für die erste Stoff- und Energieflu?analyse der Universit?t Osnabrück und die Erstellung der ?kobilanz war eine
umfangreiche und damit zeitaufwendige Datensammlung, — aufbereitung und — weiterverarbeitung. Um die Bilanzierung für die
Folgejahre zu vereinfachen und die ermittelten Daten für ein ?ko-Controlling nutzen zu k?nnen, wurde ein Konzept für ein Umweltinformationssystem
(UIS) der Universit?t erarbeitet. Es setzt sich zusammen aus der operativen Ebene mit den dezentralen Daten(banken) der Verwaltung,
einer zentralen Datenbankebene, in der die ?kobilanz erstellt und Umweltkennzahlen berechnet werden, und einer Auswertungs-
und Pr?sentationsebene als Schnittstelle zwischen Daten und ihren Nutzern. Das UIS wird mittelfristig als Teil des Management-Informationssystem
implementiert, das die Universit?t als erste Hochschule Deutschlands zur Zeit entwickelt.
相似文献
293.
Shicheng Xu Junhua Li Dong Yang Jiming Hao 《Frontiers of Environmental Science & Engineering in China》2009,3(2):186-193
The reaction mechanisms of selective catalytic reduction (SCR) of nitric oxide (NO) by methane (CH4) over solid superacid-based catalysts were proposed and testified by DRIFTS studies on transient reaction as well as by kinetic
models. Catalysts derived from different supports would lead to different reaction pathways, and the acidity of solid superacid
played an important role in determining the reaction mechanisms and the catalytic activities. Higher ratios of Br?nsted acid
sites to Lewis acid sites would lead to stronger oxidation of methane and then could facilitate the step of methane activation.
Strong Br?nsted acid sites would not necessarily lead to better catalytic performance, however, since the active surface NOy species and the corresponding reaction routes were determined by the overall acidity strength of the support. The reaction
routes where NO2 moiety was engaged as an important intermediate involved moderate oxidation of methane, the rate of which could determine
the overall activity. The reaction involving NO moiety was likely to be determined by the step of reduction of NO. Therefore,
to enhance the SCR activity of solid superacid catalysts, reactions between appropriate couples of active NOy species and activated hydrocarbon intermediates should be realized by modification of the support acidity. 相似文献
294.
L. Tacconi P. F. Moore D. Kaimowitz 《Mitigation and Adaptation Strategies for Global Change》2007,12(1):55-66
Fires have attracted interest and generated alarm since the early 1980s. This concern has been particularly evident in tropical
forests of Southeast Asia and the Amazon, but disastrous fires in recent summers in Australia, Europe, and the United States
have drawn worldwide attention.
Concern about forest fires, and related air pollution and biodiversity impacts, led international organisations and northern
countries – such as the Asian Development Bank, the European Union, the Food and Agriculture Organisation, the United Nations
Environment Programme, the World Bank, and the government of Germany – to undertake fire assessments and provide technical
assistance. Nongovernmental organisations, such as the International Union for Conservation of Nature and Natural Resources
and World Wide Fund for Nature, have also devoted increased attention to fires. Aiming at prevention of future fires, 40 fire
projects and missions costing well over US$30 million have worked in Indonesia over the last 20 years. Despite the money and
effort spent on them, fires continue to burn every year. It may appear to some that efforts to address the ‘fire problem’
have not been effective as fires still occur.
There remains a lack of clarity about ‘fire problems’, which has, at times, led to the adoption of policies that may have
negative impacts on livelihoods, the environment, and the economy. Two ‘simple’ changes in the way fires are considered would
significantly improve fire-related policies and initiatives.
These two points are discussed in the context of Southeast Asia, and particularly Indonesia, as an example of the problems
and questions faced by tropical countries. We argue that efforts on fires so far have generated increased knowledge of the
’fire problem’; now, we need to capitalize on that knowledge to avoid wasting money in the future. 相似文献
• | Fires should be seen as a component of land management processes, rather than as a ‘problem’ to be prevented, suppressed, or mitigated. |
• | Not all fires are the same. |