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Wood stabilization limits water absorption into the wood structure, thereby limiting the dimensional changes which arise from moisture exposure. Wood stabilization is a subset of wood preservation processes specifically used by woodworking enthusiasts to alter the material properties of specific wood species for applications within their craft ...
When free hydroxyl groups are transformed to acetoxy groups, the ability of the wood to absorb water is greatly reduced, rendering the wood more dimensionally stable and, because it is no longer digestible, extremely durable. In general, softwoods naturally have an acetyl content from 0.5 to 1.5% and more durable hardwoods from 2 to 4.5%.
Acetylated wood is a type of modified wood that is produced through a chemical modification process and does not contain any toxic substances. [1] It produced from a chemical reaction (named as acetylation), involving acetic anhydride and a modification process to make wood highly resistant to biological attacks by fungi and wood-boring insects and durable to environmental conditions.
in the condensation of the water-vapour of the air on the cold surface of a glass; in the capillarity of hair, wool, cotton, wood shavings, etc.; in the imbibition of water from the air by gelatine; in the deliquescence of common salt; in the absorption of water from the air by concentrated sulphuric acid; in the behaviour of quicklime". [4]
The relationship between water content and equilibrium relative humidity of a material can be displayed graphically by a curve, the so-called moisture sorption isotherm. For each humidity value, a sorption isotherm indicates the corresponding water content value at a given temperature. If the composition or quality of the material changes, then ...
Equilibrium moisture content of wood versus humidity and temperature, according to the Hailwood-Horrobin equation. The equilibrium moisture content (EMC) of a hygroscopic material surrounded at least partially by air is the moisture content at which the material is neither gaining nor losing moisture.
One example of Imbibition in nature is the absorption of water by hydrophilic colloids. Matrix potential contributes significantly to water in such substances. Dry seeds germinate in part by imbibition. Imbibition can also control circadian rhythms in Arabidopsis thaliana and (probably) other plants. The Amott test employs imbibition.
The liquid limit test is defined by ASTM standard test method D 4318. [4] The test method also allows running the test at one moisture content where 20 to 30 blows are required to close the groove; then a correction factor is applied to obtain the liquid limit from the moisture content. [5]