Biomedical Engineering Reference
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and the presence of up to 20% of such nanoparticles in the
single-wall nanotube samples studied in Ref. [95], together
with the strong agglomeration of nanotubes,in form of
strands, microcrystalline films, and “rugs” with a polycrystal-
line structure noted in Ref. [95], i.e., the presence in the single-
wall nanotube samples used in Refs. [94, 95] of graphite
multilayer nanostructures typical of the GNF samples used in
Ref. [94], where a sorption process
γ
can be supposed;
(6) The appearance (studied in Ref. [95]) in mass spectra of gases
released in the course of a multistage prolonged heating up
to 673 K in a vacuum of deuterated single-wall nanotube
samples, the prevailing contribution of hydrocarbons, and,
at the higher temperatures of a multistage heating process
(773 K for 3 h and 823 K for 3 h), the appearance of the
prevailing contribution of deuterium and HD molecules;
(a) The manifestation of only one C-H peak in the IR spectrum
of nanostructured graphite studied in Ref. [89], which
basically corresponds to C-H
configuration comparable
to the model H in Fig. 2.8 for chemisorption process II;
(b) The
occurrence of two of the three high-temperature TPD
peaks [14, 53-56, 96] (chemisorption processes II, III,
and/or IV, Table 2.1 and Fig. 2.7)
;
two peaks in the NMR
spectrum (of the Gaussian and Lorentzian types) [14,
65] and two peaks corresponding to C-H bonds, 0.11 and
0.18 nm long, in the spectrum of the neutron-diffraction
radial distribution [14];
(c) The
occurrence of two high-temperature TPD peaks
corresponding to chemisorption processes II and III in
hydrogen-saturated GNF samples [12] (see Fig. 2.6);
(d) The manifestation of a high-temperature TPD peak
corresponding to chemisorption process II in hydrogen-
saturated single-wall and multiwall nanotube samples
studied in Refs. [61, 62].
On the basis of the analysis in Refs. [10, 96] and by comparing
the above facts, we can rightfully assume that the process
2
in the
single-wall nanotube and GNF samples [94, 95], which provides
for ≤ 40% of the sorption capacity of these samples, corresponds
to the dissociative-associative chemisorption process II, which, in
particular, is characterized [10] by an accompanying release of a
small hydrocarbons amount during the thermal desorption heating
of the carbon material.
β
