under an equal N P and K level,The 15N-labled technique was used to inverstigate the effects of different fertilizing structures on cotton yield and on the fate of nitrogen in cotton field by means of pot culture.

Aiming at the tristep method smelting process of stainless steel "electrical arc furnace+multifunction converter+VOD", and centering about dephosphorization, the theoretical analysis of the feasibility of related important link in process chain for dephosphorization and chromium conservation in the earlier stage of converter process was carried out based on metallurgical thermodynamics.

In order to solve the problems,of which difficult to realize dephosphorization,hold carbon,raising temperature at the same time during high carbon steel smelted by the converter,operation methods of double control and regulation have been summarized through optimizing process in production.

In order to solve the problems,of which difficult to realize dephosphorization,hold carbon,raising temperature at the same time during high carbon steel by the converter,operation methods of double control and regulation have been summarized through optimizing process in production.

Fate and Utilization of Crop Residues and Their Effect on Soil Nitrogen Turnover;