Synthesis [edit]. Quaternary ammonium compounds are prepared by the alkylation of tertiary amines with a halocarbon. In older literature this is often called a Menshutkin reaction, however modern chemists usually refer to it simply as quaternization.uaternary ammonium compounds have also been shown to have antimicrobial activity. Certain quaternary ammonium compounds, especially those containing long alkyl chains, are used as antimicrobials and disinfectants.
Answer: XPF files are Uncommon Files primarily associated with XaoS Position File (Jan Hubicka Thomas Marsh Zoltan Kovacs and Others).
The best ones are all proprietary or confusing (FSPF and IEEE 802.1aq). FSPF is OSPF over L2, and SPB is IS-IS over L2. There are enough people that don't understand OSPF or IS-IS over L3, so there'll be resistance to the complications over the dead-simple STP. It may not be good, but it's well known, and it's limitations are well understood.