Malaman et al., "Quantitative investigation of mineral impurities of HiPco
SWCNT samples: Chemical mechanisms for purification and annealing treatments," Carbon, vol.
The diameters of CNTs used in this study decreases from 1.4 nm to 0.8 nm (m-CNTs > HiPco
2004)--two types made by the HiPCO
method and one by the electric arc method.
This diameter is very similar to the original rope size found in HiPco
SWCNT (CNI, Houston, TX) were produced by the high pressure carbon monoxide proportionation process (HiPco
) technique (Scott et al.
Kalbac et al., "Magnetic properties of iron catalyst particles in HiPco
single wall carbon nanotubes," Journal of Physical Chemistry C, vol.
For the particular SWCNT produced by the HiPco
process (56), this frequency is given by Eq.
One hundred mg of HiPco
SWNTs were added to 50 mL of a 1: 1 HN[O.sub.3]-[H.sub.2]S[O.sub.4] solution.
EMI shielding grade SWNTs with an average diameter of 0.9-2 nm and a length of individual tubes of about 3 [mmicro]m were purchased from Carbon Nanotechnologies.
In this study, different types of SWCNTs were used: HiPco
(Carbon Nanotechnologies Inc.; average diameter [d.sub.t]: ~1.0 nm)  and CoMoCAT (Southwest Nanotechnologies; [d.sub.t]: ~0.8nm) .
A 3/8" air operated Hipco
(High Pressure Equipment Company) valve is used to release the gas quickly for the foaming process.
A range of techniques have been developed for VACNT synthesis, such as HiPco
, fluidized bed , and chemical vapor deposition (CVD) , and CVD has proven to be the most effective one.