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  2. Lifting gas - Wikipedia

    en.wikipedia.org/wiki/Lifting_gas

    The amount of mass that can be lifted by hydrogen in air per unit volume at sea level, equal to the density difference between hydrogen and air, is: (1.292 - 0.090) kg/m 3 = 1.202 kg/m 3. and the buoyant force for one m 3 of hydrogen in air at sea level is: 1 m 3 × 1.202 kg/m 3 × 9.8 N/kg= 11.8 N

  3. Environmental impact of aviation - Wikipedia

    en.wikipedia.org/wiki/Environmental_impact_of...

    Aircraft noise pollution disrupts sleep, children's education and could increase cardiovascular risk. Airports can generate water pollution due to their extensive handling of jet fuel and deicing chemicals if not contained, contaminating nearby water bodies. Aviation activities emit ozone and ultrafine particles, both of which are health hazards.

  4. Decompression theory - Wikipedia

    en.wikipedia.org/wiki/Decompression_theory

    Atmospheric nitrogen has a partial pressure of approximately 0.78 bar at sea level. Air in the alveoli of the lungs is diluted by saturated water vapour (H 2 O) and carbon dioxide (CO 2), a metabolic product given off by the blood, and contains less oxygen (O 2) than atmospheric air as some of it is taken up by the blood for metabolic use. The ...

  5. Decompression sickness - Wikipedia

    en.wikipedia.org/wiki/Decompression_sickness

    A US Air Force study reports that there are few occurrences between 5,500 m (18,000 ft) and 7,500 m (24,600 ft) and 87% of incidents occurred at or above 7,500 m (24,600 ft). [ 32 ] High-altitude parachutists may reduce the risk of altitude DCS if they flush nitrogen from the body by pre-breathing pure oxygen . [ 33 ]

  6. Atmospheric chemistry - Wikipedia

    en.wikipedia.org/wiki/Atmospheric_chemistry

    Atmospheric chemistry is a branch of atmospheric science that studies the chemistry of the Earth's atmosphere and that of other planets. This multidisciplinary approach of research draws on environmental chemistry, physics, meteorology, computer modeling, oceanography, geology and volcanology, climatology and other disciplines to understand both natural and human-induced changes in atmospheric ...

  7. Latest EPA assessment shows almost no improvement in river ...

    www.aol.com/news/latest-epa-assessment-shows...

    Phosphorus levels dipped slightly while nitrogen levels remained almost exactly the same. ... The EPA established the hypoxia task force in the late 1990s to reduce nutrient pollution and shrink ...

  8. Acid Rain Program - Wikipedia

    en.wikipedia.org/wiki/Acid_Rain_Program

    The Clean Air Act Amendments of 1990 set as its primary goal the reduction of annual SO 2 emissions by 10 million tons below 1980 levels of about 18.9 million tons. To achieve these reductions by 2000, when a nationwide sulfur dioxide emissions cap of 8.95 million tons per year began, the law required a two phase tightening of operating ...

  9. Human impact on the nitrogen cycle - Wikipedia

    en.wikipedia.org/wiki/Human_impact_on_the...

    Additionally, there was a reported fourfold increase in riverine dissolved inorganic N fluxes to coasts. [6] Nitrogen is a critical limiting nutrient in many systems, including forests, wetlands, and coastal and marine ecosystems; therefore, this change in emissions and distribution of Nr has resulted in substantial consequences for aquatic and ...