石油烃污染土壤的生物修复

从中原油田污染土壤中通过实验室驯化培养分离到一组能以中原原油为碳源的快速生长的石油烃降解菌.用该组降解菌接种原油污染土壤,研究其原位生物联合修复实验,接种降解菌的各区分别种植大豆、施有机肥料、施有机肥料和锯末,与空白试样作对比.经过120d的联合修复,各区石油降解菌的总数(lgcfu/g)由接种时的5.25分别变为7.79、4.96、5.15、4.67.石油烃降解率分别达到89.4%、72.5%、76.7%、49.2%.表明分离的该组石油烃降解菌是一组高效降解菌且其与植物联合修复石油污染土壤能显著提高修复效果.     

Mechanical and Morphological Properties of Wood Plastic Biocomposites Prepared from Toughened Poly（lactic acid） and Rubber Wood Sawdust （Hevea brasiliensis）

The present research aims to utilize the acrylic Core-Shell Rubber （CSR） particles to reduce the brittleness in Wood Plastic Composites （WPC） prepared from poly（lactic acid） （PLA） and rubber wood sawdust （Hevea brasiliensis）. Experimental works consisted of two major parts. The first part concentrated on toughening PLA by using CSR particles. Mechanical tests revealed that PLA had become tougher with a more than five times increment in the impact strength when the CSR was added at only 5 wt%. The modified PLA was less stiff with the significant reductions of both elastic and flexural moduli and strengths. The second part focused on producing WPC from the toughened PLA and rubber wood sawdust. The tensile moduli and the strengths of the PLA composites increased with rubber wood content. The composites turned out to be more brittle with reductions of both the impact strength and the tensile elongation at break at all the sawdust contents. Toughening PLA/wood flour with 5 wt% CSR improved both the impact strength and the tensile elongation at break. The toughness enhancement was also depicted by the plastic deformation observed on the surfaces of fractured PLA/CSR/wood sawdust composites.