Search results
Results From The WOW.Com Content Network
According to ASHRAE standard 34, the R-number of a chemical refrigerant is assigned systematically according to its molecular structure and has between two and four digits. If there are carbon -carbon multiple bonds , there are four digits in all: the number of these bonds is the first digit and the number of carbon atoms minus one (C-1) is next.
Refrigerant. A refrigerant is a working fluid used in the refrigeration cycle of air conditioning systems and heat pumps where in most cases they undergo a repeated phase transition from a liquid to a gas and back again. Refrigerants are heavily regulated because of their toxicity and flammability and the contribution of CFC and HCFC ...
Uses. 1,1,1,2-Tetrafluoroethane is a non-flammable gas used primarily as a "high-temperature" refrigerant for domestic refrigeration and automobile air conditioners. These devices began using 1,1,1,2-tetrafluoroethane in the early 1990s as a replacement for the more environmentally harmful R-12. Retrofit kits are available to convert units that ...
Chloroform, [10] or trichloromethane (often abbreviated as TCM ), is an organochloride with the formula C H Cl 3 and a common solvent. It is a very volatile, colorless, strong-smelling, dense liquid produced on a large scale as a precursor to refrigerants and PTFE. [11]
Propylene glycol is an approved food additive for dog and sugar glider food under the category of animal feed and is generally recognized as safe for dogs, [ 63] with an LD 50 of 9 mL/kg. The LD 50 is higher for most laboratory animals (20 mL/kg). [ 64]
The law includes an exception for commercial purposes. The term commercial purpose is defined to mean any use other than for the production of consumer products containing volatile alkyl nitrites meant for inhaling or otherwise introducing volatile alkyl nitrites into the human body for euphoric or physical effects. [16]
HCFC-22 measured by the Advanced Global Atmospheric Gases Experiment ( AGAGE) in the lower atmosphere ( troposphere) at stations around the world. Abundances are given as pollution free monthly mean mole fractions in parts-per-trillion. Growth of R-22 (CFC-22) abundance in Earth's atmosphere since year 1992.
Refrigeration is any of various types of cooling of a space, substance, or system to lower and/or maintain its temperature below the ambient one (while the removed heat is ejected to a place of higher temperature). [ 1][ 2] Refrigeration is an artificial, or human-made, cooling method. [ 1][ 2] Refrigeration refers to the process by which ...