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111.
The purpose of this research was to shorten the composting period by speeding up the composting process and to obtain good quality compost that can be used in agriculture. In order to accomplish the acceleration of the process, different mixtures of feedstock were loaded to the composting containers to observe the effect of initial composition on the quality of the compost and the rate of composting. The first feedstock prepared was composed of grass, leaves and market waste whereas the second feedstock composed only of leaves and market wastes. Composting process was accomplished by applying different composting methods such as composting without manual stirring, with manual stirring, with aeration by air, with aeration by oxygen, with manual stirring and aeration by air and finally by with manual stirring and aeration by oxygen to achieve the purpose of the research. Aeration was found as a primary requirement for the acceleration of composting because it was observed that when the aeration was not applied the conversion of nutrients was very low. The high conversion efficiency of the nutrients in the feedstock with market and yard wastes-without grass-resulted in higher quality end product. The organic content of the composted yard and market wastes were monitored and the best operational parameters and methods were identified. Parameters such as temperature, moisture, pH and end-product metal contents were also monitored in the study. and the experiments were run in duplicates. Corrected C/N, (C/N)t/(C/N)initial, were used in the calculations which provided objectivity in comparison of the compost quality with respect to nutritional components. The C/N change was found to be higher in the container that was manually stirred and aerated with oxygen but with regard to the economic feasibility of the system aeration with air was preferred. Compost quality that was achieved in the study was compared to the standards of different countries with respect to the amount of metal contents in the end-product. The applicability of the end-product in agriculture depends on the level of contaminants in the compost, especially metals that have to be present only in trace amounts. 相似文献
112.
The amount of struvite (MgNH4PO4·6H2O) produced by Myxococcus xanthus as well as the culture parameter values (pH, total phosphorus, total Kjeldahl nitrogen) were dependent on the culture medium used. Struvite formation started during the exponential phase and the maximum concentration was observed at the beginning of stationary growth phase. The addition of each medium component to the liquid culture influenced the amount of crystal produced. This amount did not depend on the pH increase during the culture period. The moment of the bacterial growth phase, at which each medium component was added, influenced the struvite formation. 相似文献
113.
Annika Porsborg Nielsen Jesper Lassen Peter Sandøe 《Journal of Agricultural and Environmental Ethics》2007,20(1):13-35
Over recent decades, public participation in technology assessment has spread internationally as an attempt to overcome or
prevent societal conflicts over controversial technologies. One outcome of this new surge in public consultation initiatives
has been the increased use of participatory consensus conferences in a number of countries. Existing evaluations of consensus
conferences tend to focus on the modes of organization, as well as the outcomes, both procedural and substantial, of the conferences
they examine. Such evaluations seem to rest on the assumption that this type of procedure has universally agreed goals and
meanings, and that therefore consensus conferences can readily be interpreted and applied across national boundaries. This
article challenges this approach to consensus conferences. The core of the article is a study of national differences in ideas
about what constitutes legitimate goals for participatory arrangements. The study looks at three consensus conferences on
GMOs, which took place in France, Norway, and Denmark. Drawing on this study, the article discusses the ways in which interpretations
of the concept of participation; the value attributed to lay knowledge vs. technical expertise; as well as ideas about the
role of the layperson, are all questions that prompt entirely different answers from country to country. Further, the article
analyses these national differences within a theoretical framework of notions of democratic legitimacy. 相似文献
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Joke Muys Yves Jacquemyn Bettina Blaumeiser Laura Bourlard Nathalie Brison Saskia Bulk Patrizia Chiarappa Anne De Leener Marjan De Rademaeker Julie Désir Anne Destrée Koenraad Devriendt Annelies Dheedene Armelle Duquenne Annelies Fieuw Erik Fransen Jean-Stéphane Gatot Mauricette Jamar Sandra Janssens Jorien Kerstjens Kathelijn Keymolen Damien Lederer Björn Menten Bruno Pichon Sonia Rombout Yves Sznajer Ann Van Den Bogaert Kris Van Den Bogaert Joris Vermeesch Katrien Janssens 《黑龙江环境通报》2020,40(10):1272-1283
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This paper is concerned with the sustainable development of a self-drive tourist destination in the remote region in Northern
Australia. It first compares officially used data on visitor profiles to the information collected in the survey. Differences
between data collected and available secondary data imply that tourism planning should include collection of region-specific
tourism information to guide and mitigate potential environmental changes. Natural landscape features are the key attraction
for visitors to the region. Visitor satisfaction levels with the current state of the destination are high. However, local
residents reported perceived negative impacts of tourism, in particular on amenities and the ecology of the landscape. Visitors
also reported behavior that might contribute to environmental impacts. Implications of the findings, in the context of future
destination planning, are discussed. 相似文献
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120.
Joke Muys Bettina Blaumeiser Yves Jacquemyn Claude Bandelier Nathalie Brison Saskia Bulk Patrizia Chiarappa Winnie Courtens Anne De Leener Marjan De Rademaeker Julie Désir Anne Destrée Koenraad Devriendt Annelies Dheedene Annelies Fieuw Erik Fransen Jean-Stéphane Gatot Philip Holmgren Mauricette Jamar Sandra Janssens Kathelijn Keymolen Damien Lederer Björn Menten Marije Meuwissen Benoit Parmentier Bruno Pichon Sonia Rombout Yves Sznajer Ann Van Den Bogaert Kris Van Den Bogaert Olivier Vanakker Joris Vermeesch Katrien Janssens 《黑龙江环境通报》2018,38(13):1120-1128