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pixabay.com (GOUb) and latewood (GOUc), the intensity of the recorded
signal is from 319 to 2481 and decreases with depth.
The magnesium content in the near-surface layers of the
early wood zone (cb) of the control samples is lower than

in the latewood zone (cc), which seems to be correct. The
content of mineral components in wood is up to 1.2 percent.
Macroelements such as magnesium and calcium play
important roles in cellular processes.
In wood subjected to vacuum impregnation, a higher
of wood. intensity of the magnesium signal is observed in the near-
Ultrasound can destroy the parenchyma cells and cause surface layers (1–5 laser pulses) in the GOb cell zone compared
the ejection of cellular substances outside the cell. Ultrasound to the GOc cell zone.
can also cause cellulose destruction. The higher intensity of the magnesium signal in the near-

Therefore, it can be assumed that the low carbon intensity surface layers compared to the control results may indicate
for samples of wood impregnated without pressure in ultrasound its presence in the water used for testing. In wood subjected
results from the small presence of GO on the wood surface to ultrasound, the intensity of the magnesium signal in the
and from the release of wood compounds that are not bound GOUb zone is similar to the results obtained for the GOb zone.
to the matter by physisorption. In turn, the intensity of signals in the surface layers of the
Graphene oxide in the early and late wood zones (GOUb GOUc zone (1–3 laser pulses) is very high. It can be assumed
and GOUc) can be present on the wood surface, but the that this signal comes from impurities (magnesium ions), the

action of ultrasound can lead to a decrease in the adhesion source of which is the water used for testing.
of GO to the surface. The zeta potentials of graphene oxide Because a heterogeneous anatomical structure characterises
generated in an aqueous environment and during the action wood, the zone of early (spring) wood is anatomically different
of ultrasound can be of great importance in the adhesion of from the zone of late (summer) wood; the structure of the wood
GO to the matter. in the annual growth ring can significantly affect how wood
The intensity of the oxygen signal in the control wood in tissue interacts with substances and materials introduced into it.
the near-surface layers of the earlywood cell zone (cb) is low Early wood cells are characterised by thinner cell walls
but increases with depth. A high oxygen signal is observed and larger cell lumens, which enables them to contain a more
in the near-surface layers of latewood cells. significant number of graphene oxide flakes. Thicker cell walls

It is assumed that this is the oxygen signal originating from characterise latewood cells but are practically impermeable.
the structural components of wood. In the near-surface layers The relationship between the relative number of elements C,
of vacuum-impregnated wood, the intensity of the oxygen signal Mg, and O in wood was confirmed and the different structures
in the GOb zone is higher than in the GOc zone, which may of the wood in spring and summer growths.
indicate the appearance of oxygen-containing substances in The signal value (counts) mean the area under spectral
the near-surface layers. line of the interest (C 247 nm, Mg 279 nm, and O 777 nm,
The intensity level of the oxygen signal in the pressureless respectively) corrected for the background contribution.

ultrasonic-impregnated wood is distributed in a similar way In the control wood, the content of elements in the near-
as observed for coal. In the near-surface layers of earlywood surface layers, primarily carbon, is higher in latewood, which