• 대한가정학회지
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• 제19권4호
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• pp.9-15
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• 1981

damages of cotton cloth and characteristics of fabroid degradation were studied by Chaetomium globosum and Aspergillus niger which presupposed as powerful erosive fungi to cellulose fiber by means of tensile strength. The results obtained are as follows: 1. the growth(rate) of fungi in malt extract agar was superior to potato agar for two weeks. 2. Chaetomium globosum showed mostly severe damage t the cotton cloth in malt extract agar media at pH 4.5. 3. Tensile strength was reduced with time by Aspergillus niger-coenzyme and Chaetomium globosum-coenzyme reaction. In comparison with Chaetomium globosum and Aspergillus niger, the former weaken tensile strength about 15.8% and the latter enfeebled 10.0% after 124 hours. 4. after 30 days the breeding of fungi in pH 4.5 malt extract agar media, critical damage of cotton cloth was observe, I. e., 92.4% damage by chaetomium globosum and 74.9% lose by aspergillus nige respectively.

• Nuclear Engineering and Technology
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• 제56권5호
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• pp.1880-1886
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• 2024

To elucidate the mechanism of damage caused by hyphae and organic acids produced by Aspergillus Niger on the surface and internal structure of uranium ore, direct uranium leaching, indirect uranium leaching and semidirect uranium leaching were conducted, and the surface morphology, strength, mineral crystallinity, porosity, and permeability of the ore were analyzed. The results demonstrated that the combination of biomechanical forces exerted by hyphae and the complexation effects of organic acids led to the dissolution of SiO₂ and other substances on the surface of ore, resulting in exfoliation from the exterior to the interior, thereby promoting uranium recovery. Furthermore, the proton exchange involving H⁺ and the complexation of organic acids resulted in the dissolution of cations within the ore, causing destruction to the crystal lattice structure of minerals and increasing the porosity and permeability inside the ore. The dominant factor contributing to ore damage during recovery was organic acids.