Schematic illustration of the hierarchical structure of a tree and the interaction between cellulose nanofibers and cement particles.

<p>(a) The hierarchical structure of celluloses. (b) A network of cellulose nanofibers and cement formed with carboxyl groups and cement hydrates.</p

The microstructure of cement pastes after aging 28 days.

<p>(a) SEM image of the cement paste. (b) SEM image of cement paste with 0.15% of CNFs; (c) and (d) Pore diameter distributions of cement pastes with different CNF content.</p

Water consistency and initial and final setting times for cement pastes.

<p>Water consistency and initial and final setting times for cement pastes.</p

Degree of hydration of cement pastes at different aging times.

<p>Degree of hydration of cement pastes at different aging times.</p

DTA-TGA results of cement pastes with different CNF weight fractions from 100 to 800°C.

<p>DTA-TGA results of cement pastes with different CNF weight fractions from 100 to 800°C.</p

The relationship between mechanical strength (flexural strength and compressive strength) and DOH.

<p>The relationship between mechanical strength (flexural strength and compressive strength) and DOH.</p

The effect of CNFs addition on the pore structure.

<p>The effect of CNFs addition on the pore structure.</p

The morphology of cellulose nanofibers and the effect of CNFs on early hydration of cement particles.

<p>(a) Size distribution of CNFs; (b) TEM image of CNFs; (c) Heat flow curves of CNF-cement pastes for the first 72 hrs’ hydration; (d) Scheme of CNFs promoting the setting of the cement paste by coordination with Ca²⁺.</p

W_CH and W_b contained per gram cement paste with different CNF weight fractions.

<p>W_CH and W_b contained per gram cement paste with different CNF weight fractions.</p

MTT assay.

<p>Saponin 1 significantly inhibited the cell viabilities of glioblastoma U87MG and U251MG cells in a dose concentration- and time-dependent manner, but did not affect the cell viability of primary cultured astrocytes, as compared to the vehicle-controls. </p