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TAGHIYARI HR , RASSAM G, LOTFINEJAD SANI Y & KARIMI A. 2012. Effects of nano-silver impregnation on some mechanical properties of ice-blasted wood specimens. Ice blasting (frozen CO2, -78.5 °C) is one of the modern methods of cleaning for industrial purposes. Effects of ice blasting were studied on untreated solid wood as well as 200 ppm nano-silver impregnated wood of Populus nigra (poplar) and Fagus orientalis (beech). Modulus of rupture (MOR), modulus of elasticity (MOE) and compression strength parallel to the grain were measured. Ice blasting decreased MOR by 31.5 and 6% in poplar and beech respectively. However, when specimens were impregnated with nano-silver, MOR would only decrease by 4.8% in beech and increase by 1.7% in poplar. Ice blasting decreased MOE and compression strength parallel to the grain by 62.5 and 2.5% respectively in poplar, and 8.6 and 4.4% in beech. The lower the density of a wood the more mechanical properties would decrease in untreated wood as a result of ice blasting. On the other hand, nano-silver impregnation decreased the amount of losses in MOR, MOE and compression strength parallel to the grain. Heat conductivity of nano-silver particles transferred the cold accumulated on the surface layers of specimens. Consequently, mechanical properties would be improved by preventing the formation of microscopic fissures and surface checks.
Keywords: Cleaning, ice blasting, metal nanoparticles, solid wood
TAGHIYARI HR , RASSAM G, LOTFINEJAD SANI Y & KARIMI A. 2012. Kesan pengawetan nanoperak terhadap beberapa ciri mekanik spesimen kayu yang dibagas ais. Bagas ais (CO2 sejuk beku, -78.5 oC) merupakan salah satu kaedah pembersihan untuk tujuan industri. Kesan bagas ais terhadap kayu padu Populus nigra (poplar) dan Fagus orientalis (bic) yang tidak dirawat serta yang dirawat dengan 200 ppm nanoperak dikaji. Modulus kepecahan (MOR), modulus kekenyalan (MOE) dan kekuatan mampatan selari ira disukat. Bagas ais mengurangkan MOR sebanyak 31.5% dalam kayu poplar dan 6% dalam kayu bic. Namun, MOR cuma berkurangan sebanyak 4.8% dalam kayu bic dan bertambah sebanyak 1.7% dalam kayu poplar apabila diawet dengan nanoperak. Bagas ais mengurangkan MOE dan kekuatan mampatan selari ira masing-masing sebanyak 62.5% dan 2.5% dalam kayu poplar serta 8.6% dan 4.4% dalam kayu bic. Semakin rendah ketumpatan kayu, semakin banyak ciri mekanik akan berkurangan nilainya akibat bagas ais. Sebaliknya, rawatan nanoperak...