Intelligent Control System of BOF Steelmaking
0n the basis of analyzing BOF steelmaking characteristics, a prediction model and control model based on neural network were established. Taking endpoint temperature and endpoint carbon content as control target, oxygen-blown volume and added coolant were calculated, then endpoint control of convert steelmaking was realized. Simulation results show that the simulation result of endpoint temperature and carbon content are satisfying and control strategy is very effective. The application results demonstrate the efficiency of the method.
Magnetic Properties and Kinetics Parameters of Electroless Magnetic Loss CoFeB Films
Electroless CoFeB films with good soft magnetic properties were fabricated on polyester plastic substrate from sodium tartarate as a complexing agent. The plating rate of electroless CoFeB films is a function of concentration of sodium tetrahydroborate, pH of the plating bath, plating temperature and the metallic ratio. The estimated regression coefficient b0 2 b3 confidence interval, residual error r and confidence interval rint were confirmed by a computer program. The optimal composition of the plating bath was obtained and the dynamic electromagnetic parameters of films were measured in the 2 2 10 GHz range. At 2 GHz, the ε′, ε″ of the electroless CoFeB films were 304 and 76. 6, respectively, as the concentration of reducer is 1 g/L. Magnetic hysteresis loop of the deposited CoFeB films show a remanence close to the saturation magnetization and coercivity of about 55. 7–127. 4 A/m. The loops along the hard axis display low anisotropic field Hk of 2 388–3 582 A/m.
Photoinduced spin-state transition of Co3+ in the layered perovskite manganite thin film
The photoinduced effect, at different temperatures, on layered perovskite manganite La1.2Sr1.8Mn1.8Co0.2O7 thin film deposited on a SrTiO3(100) substrate has been studied using a He–Ne laser (632.8 nm) with the power of output 25 mW at low temperatures. The electrical transport and magnetic properties of the film are investigated systematically in the temperature region from 20 to 300 K. The resistance shows a significant decrease at low temperatures (T<90 K) under laser irradiation, which can be interpreted in terms of the spin-state transition of Co3+ ions. The magnetic field combined with the laser is also used to detect the photoinduced effect of the spin-glass state. The time dependence of the metastable system under several applied fields was also discussed. The system has the ability to keep a persistent memory of the magnetic history imprinted in its zero-field resistance.