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931.
Luciano Farias de Novaes Bruna Luckmann Saratt José Alberto Domingues Rodrigues Suzana Maria Ratusznei Deovaldo de Moraes Rogers Ribeiro Marcelo Zaiat Eugenio Foresti 《Journal of environmental management》2010,91(8):1647-1656
The objective of this work was to assess the effect of agitation rate and impeller type in two mechanically stirred sequencing batch reactors: one containing granulated biomass (denominated ASBR) and the other immobilized biomass on polyurethane foam (denominated AnSBBR). Each configuration, with total volume of 1 m3, treated 0.65 m3 sanitary wastewater at ambient temperature in 8-h cycles. Three impeller types were assessed for each reactor configuration: flat-blade turbine impeller, 45°-inclined-blade turbine impeller and helix impeller, as well as two agitation rates: 40 and 80 rpm, resulting in a combination of six experimental conditions. In addition, the ASBR was also operated at 20 rpm with a flat-blade turbine impeller and the AnSBBR was operated with a draft tube and helix impeller at 80 and 120 rpm. To quantify how impeller type and agitation rate relate to substrate consumption rate, results obtained during monitoring at the end of the cycle, as well as the time profiles during a cycle were analyzed. Increasing agitation rate from 40 rpm to 80 rpm in the AnSBBR improved substrate consumption rate whereas in the ASBR this increase destabilized the system, likely due to granule rupture caused by the higher agitation. The AnSBBR showed highest solids and substrate removal, highest kinetic constant and highest alkalinity production when using a helix impeller, 80 rpm, and no draft tube. The best condition for the ASBR was achieved with a flat-blade turbine impeller at 20 rpm. The presence of the draft tube in the AnSBBR did not show significant improvement in reactor efficiency. Furthermore, power consumption studies in these pilot scale reactors showed that power transfer required to improve mass transfer might be technically and economically feasible. 相似文献
932.
Stefan Bakker Heleen de Coninck Heleen Groenenberg 《International Journal of Greenhouse Gas Control》2010,4(2):321-326
The inclusion of CO2 capture and storage (CCS) in the Kyoto Protocol's Clean Development Mechanism (CDM) is still subject to controversy and discussion. A myriad of barriers prevents CCS in the CDM. Apart from political barriers, economic, social and procedural barriers play a role. This paper discusses relevant new results on the human capacity, procedural feasibility and economic potential of CCS in the CDM. The conclusions of a capacity building effort in Africa show that awareness and knowledge are low but that capacity building efforts are well received. A reality check on methodologies for hypothetical CCS projects shows that most of the issues can be resolved, and the CDM institutional arrangements can accommodate CCS. A bottom-up estimate of the potential of natural gas processing CCS in the CDM, based on a previously proprietary database from the oil and gas industry, suggests that there is an annual potential of about 174 MtCO2 in 2020 in that sector. Most of that potential can be realized at CER prices between $20 and $30/tCO2 but there is no sign of flooding the CDM market with cheap credits from CCS projects. Despite these results and more open information, the CCS and CDM debate, progress in the negotiations on CCS in the CDM is slow and there is no clear view on a solution. 相似文献
933.
Martin Gullstrom Maricela de la Torre Castro Salomao O.Bandeira Mats Bjork Mattis Dahlberg Nils Kautsky Patrik Ronnback Marcus C.Ohman 《Ambio-人类环境杂志》2002,31(8)
海草是海洋被子植物,广泛分布在温带和热带的海岸带水域,是地球上水生生态系统中最具生产力的生物之一. 相似文献
934.
935.
936.
IntroductionInsomespecialgeomorphic,geological,lithogeochemicalandhydrogeochemicalenvironment,thegroundwaterandsoilinsomeareas?.. 相似文献
937.
Die geschichtliche Entwicklung der kosmologischen Modelle für den homogen–isotropen Kosmos, beginnend mit Alexander Friedmanns
epochalen Arbeiten (1922 und 1924) bis zur heutigen Diskussion aktueller Modelle wird dargestellt. Eine kardinale Rolle spielt
die offene Frage: Besteht die Materie des Kosmos zum weit überwiegenden Teil aus nicht–baryonischer (sog. exotischer) Dunkel–Materie
oder reicht die gesamte baryonische Materie aus, die aus den bekannten Atomen und Molekülen besteht, um die Entwicklung des
Kosmos zu verstehen. Auch von der normalen (baryonischen) Materie im Kosmos ist nur ein geringer Anteil (etwa 20 5 Prozent) in leuchtenden Objekten (Sterne, Gas, Staub) direkt beobachtbar. Im Abschnitt 3 wird der “Einstein–Limit” für
die kosmologische Konstante erl?utert und eine leicht einsichtige Herleitung des Zahlenwertes gegeben. 相似文献
938.
939.
Miagostovich Marize Pereira Rocha Mônica Simões dos Reis Fabiane Bertoni Sampaio Marcelo Santos de Saldanha da Gama Gracie Carrijo Renata Malta Fabio Correia Rodrigues Janaína Genuino Amanda Ribeiro da Silva Assis Matheus Fumian Tulio Machado Barrocas Paulo Rubens Guimarães 《Food and environmental virology》2020,12(2):130-136
Food and Environmental Virology - The availability of drinking water is one of the main determinants of quality of life, disease prevention and the promotion of health. Viruses are important agents... 相似文献
940.
Kouloukoui Daniel Marinho Marcia Mara de Oliveira Gomes Sônia Maria da Silva de Jong Pieter Kiperstok Asher Torres Ednildo Andrade 《Mitigation and Adaptation Strategies for Global Change》2020,25(1):127-147
Mitigation and Adaptation Strategies for Global Change - The corporate sector is one of the main emitters in the world due to the production process and therefore is identified as a major... 相似文献