蒙脱石纳米复合物的制备及其吸附作用研究

对天然蒙脱石(M)矿物进行钠化改型和柱撑复合，制备了蒙脱石纳米复合物(MN)，并对其进行表征，同时研究其对黄曲霉毒素的吸附作用。结果表明：与M相比，MN的层间距和比表面积明显增大，d₍₀₀₁₎值增加到1.96 nm，比表面积达到149.68m²/g，而且孔体积增加，孔直径缩小，微孔比例提高。吸附试验表明：复合改性后，MN对黄曲霉毒素的吸附容量和吸附速率均明显优于M。这些结果提示MN可望成为性能优越的黄曲霉毒素吸附剂。     

Effect of chromium nanocomposite supplementation on growth hormone pulsatile secretion and mRNA expression in finishing pigs

The study was conducted to investigate the effect of chromium nanocomposite (CrNano) on growth hormone (GH) pulsatile secretion and pituitary GH mRNA expression in finishing pigs. Fifty‐four crossbred pigs (65.57 ± 1.05 kg initial weight) were randomly allotted to one of the three treatments, with three replicate pens per treatment and six pigs per pen. Pigs were offered one of the four diets including a control diet or a control diet supplemented with 200 μg/kg chromium from either chromium chloride (CrCl₃) or CrNano for 35 days. During the trial, all pigs were given free access to feed and water. After completion of the feeding trial, blood samples were taken via auriculares at 15 min intervals for 3 h and three pigs from each treatment were slaughtered to collect pituitary to determine GH mRNA level. The results of GH dynamic secretion showed that supplemental CrNano increased the mean level, the lowest value, peak value and peak duration of GH significantly, while there was no significant effect on peak amplitude. Pituitary mRNA expression of GH was improved significantly in pigs fed diet containing Cr from CrNano. These results indicated that CrNano increased GH mRNA expression and secretion in finishing pigs.     

CuO—ZnO纳米复合防腐剂对杨木抑菌性能的影响

以普通CuO、ZnO粉体为原料,在分散剂柠檬酸铵作用下,用纳米研磨机,通过湿法研磨技术制备CuO—ZnO纳米复合防腐剂,用激光粒度仪检测不同浓度纳米粒子粒径及其分布,参照LY／T1283—2011研究CuO—ZnO纳米复合防腐剂的抑菌性能,借助扫描电子显微镜观察木材腐朽12周后菌丝生长情况,分析复合防腐剂中药物浓度与木材抑茵性的关系以及防腐剂在木材中的留存率。结果表明：测定纳米复合防腐剂的最小平均粒径为41．7nm;CuO—ZnO纳米复合防腐剂对白腐菌和褐腐菌均有一定的抑菌性,其处理后木材的防腐性和抗流失性能均较好;药剂浓度达到1．25％时即可达到强耐腐Ⅰ级标准,此时平均载药量为4．81kg／m3,质量损失率8．2％,符合性能优良的木材防腐剂指标要求。