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916.
Sa V. Ho B. Mason Hughes Philip H. Brodsky John S. Merz Larry P. Egley 《补救:环境净化治理成本、技术与工艺杂志》1999,9(3):103-116
Originated from a recognized need for significantly more effective technologies for soil cleanup, the LasagnaTM project provides an interesting case study in which industry, government, and academia successfully collaborated to rapidly advance the technology from the laboratory to the field. Called LasagnaTM because of its layered configurations, the technology combines electrically induced contaminant transport in soils, treatment in place, and geotechnical methods to achieve completely in situ clean-up of contaminated soils. Experiences with respect to the partnership, the development of technology and its current commercialization status are described. 相似文献
917.
This investigation was carried out in eight villages situated in the Tehri district of Uttar Pradesh, Himalaya, India. The villages are at an elevation of between 500 and 1700 m. Interviews of 61 households and 347 people, which were deliberately biased towards older people, were undertaken. These revealed that there was no evidence to suggest any significant change in land-use patterns in agriculture and forestry over the last 80–100 years in spite of the ever-increasing population. The period between 1920 and 1970 is considered to be when a rapid decline occurred in the forested area. This period coincided with extensive changes in government administration. Qualitative and quantitative data about the usage of forest products are presented. Biomass forms the major fuel, using variable proportions of wood and agricultural waste. 相似文献
918.
Sarah J. Cowell Walter Wehrmeyer Peter W. Argust J. Graham S. Robertson 《Resources Policy》1999,25(4):421
This paper reflects on how sustainability is being interpreted both theoretically and in practice for the primary extraction industries. Two contrasting perspectives can be adopted: one states that continued extraction of non-renewable resources is a necessary part of sustainable development, whilst the other states that extraction of these resources must be greatly reduced or even eliminated. It is shown that these different approaches can be traced back to underlying, often unarticulated, assumptions about the acceptability of trade-offs between different societal goals; attitudes towards uncertainties in scientific analysis and the reliability of management systems; and the perceived appropriateness of system boundaries at different conceptual scales. These assumptions are founded in the self-perception of organisations and individuals about their roles in society, and the cultural context within which these organisations and individuals define their raison d'être. 相似文献
919.
Thomas B. Fischer 《Journal of Environmental Planning and Management》1999,42(2):189-219
This paper is based on research conducted in 1997 and 1998 at the EIA Centre, University of Manchester. It examines the extent to which transport infrastructure related policies, plans and programmes (PPPs) in the three EU regions of North West England, the provincie (administrativeregion) of Noord-Hollandand the engerer Verflechtungsraum (EVR, planning region) of Brandenburg-Berlinconsider (environmental) sustainability issues in the form of objectives, targets and related options/measures for action. Furthermore, the role strategic environmental assessment (SEA) appears to play in this context is elaborated. The analytical framework for comparison is based on the sustainable development strategy of the European Commission, the Fifth Action Programme (Commission of the European Communities, 1993). 相似文献
920.
A. J. Geffen 《Marine Biology》1999,134(4):637-643
Sperm characteristics and fertilization success were measured in two groups of Manx autumn-spawning herring, Clupea harengus L., captured 1 wk apart. Samples contained motile sperm for up to 45 min after activation (average 7 min). Individual spermatozoa
were motile for up to 5 min. The activation of individual spermatozoa is probably phased, although the mechanism for the delay
is not clear. This can account for the overall low levels of active sperm at any one time, the periodic fluctuations observed
in the proportion of motile sperm, and for successful fertilization rates achieved using samples of apparently immotile sperm.
The proportion of motile sperm was not affected by the presence of eggs, but the duration of motility was longer when sperm
was activated in the presence of eggs rather than in seawater alone. Individual males differed significantly in the duration
of motility in their sperm samples and in the fertilization rates achieved, but not in the proportion of motile sperm in each
sample. There were no consistent changes in the characteristics of the spawners or the sperm between the two sample dates.
Sperm motility and duration of motility were significantly correlated, but none of the sperm characteristics measured was
significantly related to fertilization success.
Received: 13 March 1999 / Accepted: 20 May 1999 相似文献