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As an additional environmental concern, R-22 is a powerful greenhouse gas with a GWP equal to 1810 (which indicates 1810 times as powerful as carbon dioxide). Hydrofluorocarbons (HFCs) are often substituted for R-22 because of their lower ozone depletion potential, but these refrigerants often have a higher GWP.
The alveolar oxygen partial pressure is lower than the atmospheric O 2 partial pressure for two reasons. Firstly, as the air enters the lungs, it is humidified by the upper airway and thus the partial pressure of water vapour (47 mmHg) reduces the oxygen partial pressure to about 150 mmHg.
From 1930 to 1935, they developed dichlorodifluoromethane (CCl 2 F 2 or R12), trichlorofluoromethane (CCl 3 F or R11), chlorodifluoromethane (CHClF 2 or R22), trichlorotrifluoroethane (CCl 2 FCClF 2 or R113), and dichlorotetrafluoroethane (CClF 2 CClF 2 or R114), through Kinetic Chemicals which was a joint venture between DuPont and General Motors.
(In normal individuals, carbon dioxide is the primary determinant of respiratory drive.) Lung function development is reduced in children who grow up near motorways [5] [6] although this seems at least in part reversible. [7] Air pollution exposure affects FEV 1 in asthmatics, but also affects FVC and FEV 1 in healthy adults even at low ...
Normal boiling points for pure substances, bubble and dew points for zeotropic blends, or normal boiling point and azeotropic temperature for the azeotropic blends, at 101,325 Pa (1 atmosphere) and in degrees Celsius; Critical temperature in degrees Celsius; Absolute critical pressure in kilopascals
This standard is also called normal temperature and pressure (abbreviated as NTP). However, a common temperature and pressure in use by NIST for thermodynamic experiments is 298.15 K (25 °C, 77 °F) and 1 bar (14.5038 psi , 100 kPa ).
From electronics to medications, here's a list of things you shouldn't leave in your car as freezing temperatures blast most of the U.S.
Kettering patented a refrigerating apparatus to use the gas; this was issued to Frigidaire, a wholly owned subsidiary of General Motors. [5] In 1930, General Motors and DuPont formed Kinetic Chemicals to produce Freon. Their product was dichlorodifluoromethane and is now designated "Freon-12", "R-12", or "CFC-12".