Heat pump the brand name Freon, a trademark of DuPont. Its manufacture is now banned or severely restricted by the Montreal Protocol of August 1987 because of the damage that CFCs cause to the ozone layer if released into the atmosphere. One widely adopted replacement refrigerant is the hydrofluorocarbon (HFC) known as R-134a (1,1,1,2-tetrafluoroethane). Heat pumps using R-134a replaced R-12 (dichlorodifluoromethane) and have similar thermodynamic properties but with insignificant ozone depletion potential and a somewhat lower global warming potential. Other substances such as liquid R-717 ammonia are widely used in large-scale systems, or occasionally the less corrosive but more flammable propane or
Beyond Protocol the community project "After Protocol" as open source continuation. In a 2008 GameSpy preview, Beyond Protocol was hailed for its "Customizable units; incredibly deep strategy; economic wheeling and dealing; player democracy", while noting concerns about balancing. Beyond Protocol Beyond Protocol was a subscription based Sci-Fi Massively multiplayer online real-time strategy game (MMORTS) Computer Game developed by the American independent game developer Dark Sky Entertainment and released in November 2008. The 3D game modelled a persistent and player-driven fictional galaxy. Beyond Protocol was an entirely Player versus player (PvP) game, no Non-player characters (NPCs) exist within the game, all activities (trade,