Effect of Carbide and Nitride Addition on the Strength of Sintered TiC-Mo2C-Ni Carbides

Feeding experiments were conducted quantitatively to examine the breakdown of mineral grains by earthworm, Eisenia feida, and larva of beetle, Protaetia lugubris insperata. Crushed and sieved test minerals of K-feldspar and/or quartz were mixed with artificial humus that contained no mineral grains. The mixture was fed to the soil animals in the plastic containers. After 1-, 4- and 7-day experimental durations, the ingested mineral grains were collected from the casts excreted by the soil animals in each container. Even 1 day after feeding of mineral grains, the casts of soil animals contained finer, rounded mineral grains that were not included in the initial prepared mineral samples.