蛋鸡对日粮镁水平的反应

试验采用玉米-豆饼型试验日粮,高镁组（6000×10-6,MgO）鸡血液中镁含量显著高于中镁组（1200×10-6,MgO）和对照组（0．00×10-6,MgO）（P＜0．05）,中镁组与对照组间无显著差异（P＞0．05）,而血液中其他矿物元素含量三组间无显著差异（P＞0．05）。在肝脏中,高镁组的磷沉积量显著低于中镜组和对照组（P＜0.05）,而中镁组与对照组间无显著差异（P＞0．05）,其他矿物元素沉积量三组间无显著差异（P＞0.05）。在脾脏、肾脏、胰脏中镁、其他矿物元素的含量及沉积量三组间无显著差异（P＞0.05）。肝脏、脾脏、肾脏、胰脏的鲜重三组间无显著差异（P＞0．05）。     

Microstructure and Corrosion Performance of Carbonitriding Layers on Cast Iron by Plasma Electrolytic Carbonitriding

The surface carbonitriding of cast iron is investigated in an aqueous solution of acetamide and glycerin. Microstructure, chemical and phase composition and corrosion performance of the carbonitriding layers are investigated by scanning electron microscopy, energy dispersive spectroscopy and x-ray diffraction, as well as potentiodynamic polarization testing. X-ray diffraction results show that the carbonitriding coatings are composed of martensite, anstenite（γ-Fe）, Fe2C, Fe3C, Fe5 C2, FeN and ε-Fe2-3N. After the plasma electrolytic carbonitriding treatment the corrosion resistance of cast iron is clearly improved compared to the substrate, and the coatings produced at 350 V for 30s give the best corrosion resistance.