The most common shielding gases used for these main arc welding processes include argon (Ar), helium (He), carbon dioxide (CO2) and oxygen (O2). While Ar, He and CO2 may be used by themselves (i.e. 100%) for certain applications, in other cases the four gases are mixed together in different combinations to form shielding gas blends.
Cluster reduction in speech is when a consonant cluster, that is two or three consonants occurring in sequence in a word (like ândâ in friend), is reduced by a child into a single consonant through omission.
Many languages forbid consonant clusters entirely. Hawaiian, like most Malayo-Polynesian languages, is of this sort. Japanese is almost as strict, but allows a sequence of a nasal or approximant, plus another consonant, as in HonshÅ« [hoÉ´ÉuË] (the name of the largest island of Japan), and Tokyo [toËkjoË]. Standard Arabic forbids initial consonant clusters and more than two consecutive consonants in other positions.