Soldering (see RoHS), has led to a change in formulation of both solders and fluxes. Water-soluble non-rosin-based fluxes have been increasingly used since the 1980s so that soldered boards can be cleaned with water or water-based cleaners. This eliminates hazardous solvents from the production environment, and from factory effluents. Those regulations have also reduced the use of lead based solders, and caused the melting temperatures of solders in use to increase by up to . "Hot-bar reflow" is a selective soldering process where two pre-fluxed, solder coated parts are heated with heating element (called a thermode) to a sufficient temperature to
Hard and soft C Hard and soft C In the Latin-based orthographies of many European languages (including English), a distinction between hard and soft occurs in which represents two distinct phonemes. The sound of a hard (which often precedes the non-front vowels , and ) is that of the voiceless velar stop, (as in "car") while the sound of a soft (typically before , and ), depending on language, may be a fricative or affricate. In English, the sound of soft is (as in "citrus"). There was no soft in classical Latin, where it was always pronounced as . Modern English pronunciation of early