In order to reduce the materials cost of COREX ironmaking process,sinter has been introduced into the composite burden in China.This work explored the reducing process of sinter in COREX shaft furnace to clarify its r...In order to reduce the materials cost of COREX ironmaking process,sinter has been introduced into the composite burden in China.This work explored the reducing process of sinter in COREX shaft furnace to clarify its reduction properties change and then the effect of sinter proportion on metallurgical performance of composite burden was investigated.The results show that the reducing process of sinter in COREX shaft furnace was basically same with that in blast furnace but sinter seems like breaking faster.Under reducing condition simulated COREX shaft furnace,sinter possessed the worst reduction degradation index(RDI)and undifferentiated reduction index(RI)compared with pellet and iron ore lumps.Macroscopic and microscopic mineralogy changes indicated that sinter presents integral cracking while pellet and lump ore present surface cracking,and no simple congruent relationship exists between cracks of the burden and its ultimate reduction degradation performance.The existence of partial metallurgical performance superposition between composite and single ferrous burden was confirmed.RDI_(+6.3)≥70%and RDI_(+3.15)≥80%were speculated as essential requirements for the composite burden containing sinter in COREX shaft furnace.展开更多
After the “two sessions” held this year, the state has continuously implemented massive tax and fee cuts. Deepening VAT reform is undoubtedly one of the “main course” in this “big meal” of tax and fee cuts, and ...After the “two sessions” held this year, the state has continuously implemented massive tax and fee cuts. Deepening VAT reform is undoubtedly one of the “main course” in this “big meal” of tax and fee cuts, and the real economy is the main service ob-ject of this “main course”.展开更多
The meaning of the term“reduction”in Double Reduction Policy implores teachers to reflect on their teaching process and improve teaching efficiency.Not only should the quantity be reduced,but so should the behavior....The meaning of the term“reduction”in Double Reduction Policy implores teachers to reflect on their teaching process and improve teaching efficiency.Not only should the quantity be reduced,but so should the behavior.Having a comprehensive understanding of the students’learning process is actually a form of science.Therefore,we need to study and enhance its development[1].In order to reduce the learning burden and increase the efficiency of classroom teaching,we must clearly identify the inefficient and ineffective behaviors in classroom teaching,so as to avoid the following situations:a lack of deep thinking,a lack of ability in lesson preparation,fragmentation of questions and answers,a lack of questions that highlight the key points,anticlimax teaching process,and the habit of running over time in class[2,3].On this basis,this paper elaborates the current education state and clarifies the basic requirements of effective classroom teaching.Meanwhile,to reduce students’workload and increase the efficiency in carrying out assignments,much attention should be paid to optimizing assignment design and refining homework review and feedback.The purpose is to assign homework with an appropriate amount(achievable),precision(targeted),and suitability(personalized).Putting an end to the repetitious and unified training is not enough to improve the effect.展开更多
基金Project(2019JJ51007)supported by the Natural Science Foundation of Hunan Province,China。
文摘In order to reduce the materials cost of COREX ironmaking process,sinter has been introduced into the composite burden in China.This work explored the reducing process of sinter in COREX shaft furnace to clarify its reduction properties change and then the effect of sinter proportion on metallurgical performance of composite burden was investigated.The results show that the reducing process of sinter in COREX shaft furnace was basically same with that in blast furnace but sinter seems like breaking faster.Under reducing condition simulated COREX shaft furnace,sinter possessed the worst reduction degradation index(RDI)and undifferentiated reduction index(RI)compared with pellet and iron ore lumps.Macroscopic and microscopic mineralogy changes indicated that sinter presents integral cracking while pellet and lump ore present surface cracking,and no simple congruent relationship exists between cracks of the burden and its ultimate reduction degradation performance.The existence of partial metallurgical performance superposition between composite and single ferrous burden was confirmed.RDI_(+6.3)≥70%and RDI_(+3.15)≥80%were speculated as essential requirements for the composite burden containing sinter in COREX shaft furnace.
文摘After the “two sessions” held this year, the state has continuously implemented massive tax and fee cuts. Deepening VAT reform is undoubtedly one of the “main course” in this “big meal” of tax and fee cuts, and the real economy is the main service ob-ject of this “main course”.
文摘The meaning of the term“reduction”in Double Reduction Policy implores teachers to reflect on their teaching process and improve teaching efficiency.Not only should the quantity be reduced,but so should the behavior.Having a comprehensive understanding of the students’learning process is actually a form of science.Therefore,we need to study and enhance its development[1].In order to reduce the learning burden and increase the efficiency of classroom teaching,we must clearly identify the inefficient and ineffective behaviors in classroom teaching,so as to avoid the following situations:a lack of deep thinking,a lack of ability in lesson preparation,fragmentation of questions and answers,a lack of questions that highlight the key points,anticlimax teaching process,and the habit of running over time in class[2,3].On this basis,this paper elaborates the current education state and clarifies the basic requirements of effective classroom teaching.Meanwhile,to reduce students’workload and increase the efficiency in carrying out assignments,much attention should be paid to optimizing assignment design and refining homework review and feedback.The purpose is to assign homework with an appropriate amount(achievable),precision(targeted),and suitability(personalized).Putting an end to the repetitious and unified training is not enough to improve the effect.
