Search for dissertations about: "reduced nitrogen"

Showing result 21 - 25 of 234 swedish dissertations containing the words reduced nitrogen.

2. 21. Ammonia assimilation and nitrogen fixation in phototrophic bacteria : studies on glutamine synthease and the metabolic regulation of nitrogenase in Rhodospirillum rubrum

   Author : Abdelhamid Soliman; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES;

   Abstract : The phototrophic bacteria and a few other species, are able to control nitrogen fixation on the metabolic level. This is a fast and reversible mechanism, which “switches off and on” the nitrogenase activity in response to the accessibility of combined nitrogen, the energy supply and the level of oxygen in the medium. READ MORE

4. 22. Molecular mechanisms of nitrogen dioxide induced lung damage

   Author : Ba Tu; Karolinska Institutet; Karolinska Institutet; []
   Keywords : ;

   Abstract : Nitrogen dioxide (NO2) is an oxidant gas which contaminates ambient air in many urban and industrial locations, and indoor air in homes with combustion appliances. The Environmental Protection Agency (USA) regulates N02 in ambient air as a "criteria" pollutant. READ MORE

5. 23. Experimental Investigations on Natural Gas-Diesel Dual Fuel Combustion

   Author : Pablo Garcia; Förbränningsmotorer; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Dual Fuel; Diesel; Natural Gas; Pilot Injection; Combustion Efficiency; Methane; Nitrogen Oxides; Lean operation; Ignition;

   Abstract : Natural gas has been traditionally applied in spark-ignited combustion engines due to similar combustion characteristics for methane gas and gasoline. However, spark ignition requires a low compression ratio to avoid knock problems and therefore, gas engines have lower efficiency than diesel engines. READ MORE

6. 24. External Growth Control of Baltic Sea Cyanobacteria

   Author : Anna Zakrisson; Ulf Larsson; Jakob Walve; Elena Gorokhova; Sanna Suikkanen; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Baltic Sea; cyanobacteria; nitrogen fixation; heterocysts; Aphanizomenon; Nodularia; water treatment; Himmerfjärden; sewage; climate; Marine Ecology; marin ekologi;

   Abstract : In the Himmerfjärden Bay a large excess of nitrogen over phosphorus in the discharge from a large sewage treatment plant (STP) has suppressed growth of diazotrophic cyanobacteria in its inner parts. Implementation of nitrogen removal in the STP in 1997 drastically reduced nitrogen load and triggered growth of diazotrophs, mainly Aphanizomenon sp. READ MORE

7. 25. Nitritation and denitritation in sludge liquor treatment

   Author : David Gustavsson; Avdelningen för kemiteknik; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nitritation; denitritation; nitrous oxide; nitric oxide; nitrogen dioxide; wastewater; sludge liquor;

   Abstract : Enhanced biological nitrogen removal at municipal wastewater treatment plants is a common procedure to prevent eutrophication in water bodies. Increased load, stricter effluent regulations, and demands for reduced resource and energy consumption present new challenges for the wastewater treatment plants. READ MORE