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.
Stop consonant - Classification. 1  Voiced stops are pronounced with vibration of the vocal cords, voiceless stops without. 2  In aspirated stops, the vocal cords (vocal folds) are abducted at the time of release. 3  In a geminate or long consonant, the occlusion lasts longer than in simple consonants.